1/* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
4 Free Software Foundation, Inc.
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 2, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
17
18You should have received a copy of the GNU General Public License
19along with GCC; see the file COPYING. If not, write to the Free
20Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
2102110-1301, USA. */
22
23
24/* This file is part of the C front end.
25 It contains routines to build C expressions given their operands,
26 including computing the types of the result, C-specific error checks,
27 and some optimization. */
28
29#include "config.h"
30#include "system.h"
31#include "coretypes.h"
32#include "tm.h"
33#include "rtl.h"
34#include "tree.h"
35#include "langhooks.h"
36#include "c-tree.h"
37#include "tm_p.h"
38#include "flags.h"
39#include "output.h"
40#include "expr.h"
41#include "toplev.h"
42#include "intl.h"
43#include "ggc.h"
44#include "target.h"
45#include "tree-iterator.h"
46#include "tree-gimple.h"
47#include "tree-flow.h"
48
49/* Possible cases of implicit bad conversions. Used to select
50 diagnostic messages in convert_for_assignment. */
51enum impl_conv {
52 ic_argpass,
53 ic_argpass_nonproto,
54 ic_assign,
55 ic_init,
56 ic_return
57};
58
59/* The level of nesting inside "__alignof__". */
60int in_alignof;
61
62/* The level of nesting inside "sizeof". */
63int in_sizeof;
64
65/* The level of nesting inside "typeof". */
66int in_typeof;
67
68struct c_label_context_se *label_context_stack_se;
69struct c_label_context_vm *label_context_stack_vm;
70
71/* Nonzero if we've already printed a "missing braces around initializer"
72 message within this initializer. */
73static int missing_braces_mentioned;
74
75static int require_constant_value;
76static int require_constant_elements;
77
78static bool null_pointer_constant_p (tree);
79static tree qualify_type (tree, tree);
80static int tagged_types_tu_compatible_p (tree, tree);
81static int comp_target_types (tree, tree);
82static int function_types_compatible_p (tree, tree);
83static int type_lists_compatible_p (tree, tree);
84static tree decl_constant_value_for_broken_optimization (tree);
85static tree lookup_field (tree, tree);
86static tree convert_arguments (tree, tree, tree, tree);
87static tree pointer_diff (tree, tree);
88static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree,
89 int);
90static tree valid_compound_expr_initializer (tree, tree);
91static void push_string (const char *);
92static void push_member_name (tree);
93static int spelling_length (void);
94static char *print_spelling (char *);
95static void warning_init (const char *);
96static tree digest_init (tree, tree, bool, int);
97static void output_init_element (tree, bool, tree, tree, int);
98static void output_pending_init_elements (int);
99static int set_designator (int);
100static void push_range_stack (tree);
101static void add_pending_init (tree, tree);
102static void set_nonincremental_init (void);
103static void set_nonincremental_init_from_string (tree);
104static tree find_init_member (tree);
105static void readonly_error (tree, enum lvalue_use);
106static int lvalue_or_else (tree, enum lvalue_use);
107static int lvalue_p (tree);
108static void record_maybe_used_decl (tree);
109static int comptypes_internal (tree, tree);
110
111/* Return true if EXP is a null pointer constant, false otherwise. */
112
113static bool
114null_pointer_constant_p (tree expr)
115{
116 /* This should really operate on c_expr structures, but they aren't
117 yet available everywhere required. */
118 tree type = TREE_TYPE (expr);
119 return (TREE_CODE (expr) == INTEGER_CST
120 && !TREE_CONSTANT_OVERFLOW (expr)
121 && integer_zerop (expr)
122 && (INTEGRAL_TYPE_P (type)
123 || (TREE_CODE (type) == POINTER_TYPE
124 && VOID_TYPE_P (TREE_TYPE (type))
125 && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED)));
126}
127 /* This is a cache to hold if two types are compatible or not. */
128
129struct tagged_tu_seen_cache {
130 const struct tagged_tu_seen_cache * next;
131 tree t1;
132 tree t2;
133 /* The return value of tagged_types_tu_compatible_p if we had seen
134 these two types already. */
135 int val;
136};
137
138static const struct tagged_tu_seen_cache * tagged_tu_seen_base;
139static void free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *);
140
141/* Do `exp = require_complete_type (exp);' to make sure exp
142 does not have an incomplete type. (That includes void types.) */
143
144tree
145require_complete_type (tree value)
146{
147 tree type = TREE_TYPE (value);
148
149 if (value == error_mark_node || type == error_mark_node)
150 return error_mark_node;
151
152 /* First, detect a valid value with a complete type. */
153 if (COMPLETE_TYPE_P (type))
154 return value;
155
156 c_incomplete_type_error (value, type);
157 return error_mark_node;
158}
159
160/* Print an error message for invalid use of an incomplete type.
161 VALUE is the expression that was used (or 0 if that isn't known)
162 and TYPE is the type that was invalid. */
163
164void
165c_incomplete_type_error (tree value, tree type)
166{
167 const char *type_code_string;
168
169 /* Avoid duplicate error message. */
170 if (TREE_CODE (type) == ERROR_MARK)
171 return;
172
173 if (value != 0 && (TREE_CODE (value) == VAR_DECL
174 || TREE_CODE (value) == PARM_DECL))
175 error ("%qD has an incomplete type", value);
176 else
177 {
178 retry:
179 /* We must print an error message. Be clever about what it says. */
180
181 switch (TREE_CODE (type))
182 {
183 case RECORD_TYPE:
184 type_code_string = "struct";
185 break;
186
187 case UNION_TYPE:
188 type_code_string = "union";
189 break;
190
191 case ENUMERAL_TYPE:
192 type_code_string = "enum";
193 break;
194
195 case VOID_TYPE:
196 error ("invalid use of void expression");
197 return;
198
199 case ARRAY_TYPE:
200 if (TYPE_DOMAIN (type))
201 {
202 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
203 {
204 error ("invalid use of flexible array member");
205 return;
206 }
207 type = TREE_TYPE (type);
208 goto retry;
209 }
210 error ("invalid use of array with unspecified bounds");
211 return;
212
213 default:
214 gcc_unreachable ();
215 }
216
217 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
218 error ("invalid use of undefined type %<%s %E%>",
219 type_code_string, TYPE_NAME (type));
220 else
221 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
222 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type));
223 }
224}
225
226/* Given a type, apply default promotions wrt unnamed function
227 arguments and return the new type. */
228
229tree
230c_type_promotes_to (tree type)
231{
232 if (TYPE_MAIN_VARIANT (type) == float_type_node)
233 return double_type_node;
234
235 if (c_promoting_integer_type_p (type))
236 {
237 /* Preserve unsignedness if not really getting any wider. */
238 if (TYPE_UNSIGNED (type)
239 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
240 return unsigned_type_node;
241 return integer_type_node;
242 }
243
244 return type;
245}
246
247/* Return a variant of TYPE which has all the type qualifiers of LIKE
248 as well as those of TYPE. */
249
250static tree
251qualify_type (tree type, tree like)
252{
253 return c_build_qualified_type (type,
254 TYPE_QUALS (type) | TYPE_QUALS (like));
255}
256
257/* Return true iff the given tree T is a variable length array. */
258
259bool
260c_vla_type_p (tree t)
261{
262 if (TREE_CODE (t) == ARRAY_TYPE
263 && C_TYPE_VARIABLE_SIZE (t))
264 return true;
265 return false;
266}
267
268/* Return the composite type of two compatible types.
269
270 We assume that comptypes has already been done and returned
271 nonzero; if that isn't so, this may crash. In particular, we
272 assume that qualifiers match. */
273
274tree
275composite_type (tree t1, tree t2)
276{
277 enum tree_code code1;
278 enum tree_code code2;
279 tree attributes;
280
281 /* Save time if the two types are the same. */
282
283 if (t1 == t2) return t1;
284
285 /* If one type is nonsense, use the other. */
286 if (t1 == error_mark_node)
287 return t2;
288 if (t2 == error_mark_node)
289 return t1;
290
291 code1 = TREE_CODE (t1);
292 code2 = TREE_CODE (t2);
293
294 /* Merge the attributes. */
295 attributes = targetm.merge_type_attributes (t1, t2);
296
297 /* If one is an enumerated type and the other is the compatible
298 integer type, the composite type might be either of the two
299 (DR#013 question 3). For consistency, use the enumerated type as
300 the composite type. */
301
302 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
303 return t1;
304 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
305 return t2;
306
307 gcc_assert (code1 == code2);
308
309 switch (code1)
310 {
311 case POINTER_TYPE:
312 /* For two pointers, do this recursively on the target type. */
313 {
314 tree pointed_to_1 = TREE_TYPE (t1);
315 tree pointed_to_2 = TREE_TYPE (t2);
316 tree target = composite_type (pointed_to_1, pointed_to_2);
317 t1 = build_pointer_type (target);
318 t1 = build_type_attribute_variant (t1, attributes);
319 return qualify_type (t1, t2);
320 }
321
322 case ARRAY_TYPE:
323 {
324 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
325 int quals;
326 tree unqual_elt;
327 tree d1 = TYPE_DOMAIN (t1);
328 tree d2 = TYPE_DOMAIN (t2);
329 bool d1_variable, d2_variable;
330 bool d1_zero, d2_zero;
331
332 /* We should not have any type quals on arrays at all. */
333 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2));
334
335 d1_zero = d1 == 0 || !TYPE_MAX_VALUE (d1);
336 d2_zero = d2 == 0 || !TYPE_MAX_VALUE (d2);
337
338 d1_variable = (!d1_zero
339 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
340 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
341 d2_variable = (!d2_zero
342 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
343 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
344 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
345 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
346
347 /* Save space: see if the result is identical to one of the args. */
348 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)
349 && (d2_variable || d2_zero || !d1_variable))
350 return build_type_attribute_variant (t1, attributes);
351 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)
352 && (d1_variable || d1_zero || !d2_variable))
353 return build_type_attribute_variant (t2, attributes);
354
355 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
356 return build_type_attribute_variant (t1, attributes);
357 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
358 return build_type_attribute_variant (t2, attributes);
359
360 /* Merge the element types, and have a size if either arg has
361 one. We may have qualifiers on the element types. To set
362 up TYPE_MAIN_VARIANT correctly, we need to form the
363 composite of the unqualified types and add the qualifiers
364 back at the end. */
365 quals = TYPE_QUALS (strip_array_types (elt));
366 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
367 t1 = build_array_type (unqual_elt,
368 TYPE_DOMAIN ((TYPE_DOMAIN (t1)
369 && (d2_variable
370 || d2_zero
371 || !d1_variable))
372 ? t1
373 : t2));
374 t1 = c_build_qualified_type (t1, quals);
375 return build_type_attribute_variant (t1, attributes);
376 }
377
378 case ENUMERAL_TYPE:
379 case RECORD_TYPE:
380 case UNION_TYPE:
381 if (attributes != NULL)
382 {
383 /* Try harder not to create a new aggregate type. */
384 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
385 return t1;
386 if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
387 return t2;
388 }
389 return build_type_attribute_variant (t1, attributes);
390
391 case FUNCTION_TYPE:
392 /* Function types: prefer the one that specified arg types.
393 If both do, merge the arg types. Also merge the return types. */
394 {
395 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
396 tree p1 = TYPE_ARG_TYPES (t1);
397 tree p2 = TYPE_ARG_TYPES (t2);
398 int len;
399 tree newargs, n;
400 int i;
401
402 /* Save space: see if the result is identical to one of the args. */
403 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
404 return build_type_attribute_variant (t1, attributes);
405 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
406 return build_type_attribute_variant (t2, attributes);
407
408 /* Simple way if one arg fails to specify argument types. */
409 if (TYPE_ARG_TYPES (t1) == 0)
410 {
411 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
412 t1 = build_type_attribute_variant (t1, attributes);
413 return qualify_type (t1, t2);
414 }
415 if (TYPE_ARG_TYPES (t2) == 0)
416 {
417 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
418 t1 = build_type_attribute_variant (t1, attributes);
419 return qualify_type (t1, t2);
420 }
421
422 /* If both args specify argument types, we must merge the two
423 lists, argument by argument. */
424 /* Tell global_bindings_p to return false so that variable_size
425 doesn't die on VLAs in parameter types. */
426 c_override_global_bindings_to_false = true;
427
428 len = list_length (p1);
429 newargs = 0;
430
431 for (i = 0; i < len; i++)
432 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
433
434 n = newargs;
435
436 for (; p1;
437 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
438 {
439 /* A null type means arg type is not specified.
440 Take whatever the other function type has. */
441 if (TREE_VALUE (p1) == 0)
442 {
443 TREE_VALUE (n) = TREE_VALUE (p2);
444 goto parm_done;
445 }
446 if (TREE_VALUE (p2) == 0)
447 {
448 TREE_VALUE (n) = TREE_VALUE (p1);
449 goto parm_done;
450 }
451
452 /* Given wait (union {union wait *u; int *i} *)
453 and wait (union wait *),
454 prefer union wait * as type of parm. */
455 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
456 && TREE_VALUE (p1) != TREE_VALUE (p2))
457 {
458 tree memb;
459 tree mv2 = TREE_VALUE (p2);
460 if (mv2 && mv2 != error_mark_node
461 && TREE_CODE (mv2) != ARRAY_TYPE)
462 mv2 = TYPE_MAIN_VARIANT (mv2);
463 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
464 memb; memb = TREE_CHAIN (memb))
465 {
466 tree mv3 = TREE_TYPE (memb);
467 if (mv3 && mv3 != error_mark_node
468 && TREE_CODE (mv3) != ARRAY_TYPE)
469 mv3 = TYPE_MAIN_VARIANT (mv3);
470 if (comptypes (mv3, mv2))
471 {
472 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
473 TREE_VALUE (p2));
474 if (pedantic)
475 pedwarn ("function types not truly compatible in ISO C");
476 goto parm_done;
477 }
478 }
479 }
480 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
481 && TREE_VALUE (p2) != TREE_VALUE (p1))
482 {
483 tree memb;
484 tree mv1 = TREE_VALUE (p1);
485 if (mv1 && mv1 != error_mark_node
486 && TREE_CODE (mv1) != ARRAY_TYPE)
487 mv1 = TYPE_MAIN_VARIANT (mv1);
488 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
489 memb; memb = TREE_CHAIN (memb))
490 {
491 tree mv3 = TREE_TYPE (memb);
492 if (mv3 && mv3 != error_mark_node
493 && TREE_CODE (mv3) != ARRAY_TYPE)
494 mv3 = TYPE_MAIN_VARIANT (mv3);
495 if (comptypes (mv3, mv1))
496 {
497 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
498 TREE_VALUE (p1));
499 if (pedantic)
500 pedwarn ("function types not truly compatible in ISO C");
501 goto parm_done;
502 }
503 }
504 }
505 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
506 parm_done: ;
507 }
508
509 c_override_global_bindings_to_false = false;
510 t1 = build_function_type (valtype, newargs);
511 t1 = qualify_type (t1, t2);
512 /* ... falls through ... */
513 }
514
515 default:
516 return build_type_attribute_variant (t1, attributes);
517 }
518
519}
520
521/* Return the type of a conditional expression between pointers to
522 possibly differently qualified versions of compatible types.
523
524 We assume that comp_target_types has already been done and returned
525 nonzero; if that isn't so, this may crash. */
526
527static tree
528common_pointer_type (tree t1, tree t2)
529{
530 tree attributes;
531 tree pointed_to_1, mv1;
532 tree pointed_to_2, mv2;
533 tree target;
534
535 /* Save time if the two types are the same. */
536
537 if (t1 == t2) return t1;
538
539 /* If one type is nonsense, use the other. */
540 if (t1 == error_mark_node)
541 return t2;
542 if (t2 == error_mark_node)
543 return t1;
544
545 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
546 && TREE_CODE (t2) == POINTER_TYPE);
547
548 /* Merge the attributes. */
549 attributes = targetm.merge_type_attributes (t1, t2);
550
551 /* Find the composite type of the target types, and combine the
552 qualifiers of the two types' targets. Do not lose qualifiers on
553 array element types by taking the TYPE_MAIN_VARIANT. */
554 mv1 = pointed_to_1 = TREE_TYPE (t1);
555 mv2 = pointed_to_2 = TREE_TYPE (t2);
556 if (TREE_CODE (mv1) != ARRAY_TYPE)
557 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
558 if (TREE_CODE (mv2) != ARRAY_TYPE)
559 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
560 target = composite_type (mv1, mv2);
561 t1 = build_pointer_type (c_build_qualified_type
562 (target,
563 TYPE_QUALS (pointed_to_1) |
564 TYPE_QUALS (pointed_to_2)));
565 return build_type_attribute_variant (t1, attributes);
566}
567
568/* Return the common type for two arithmetic types under the usual
569 arithmetic conversions. The default conversions have already been
570 applied, and enumerated types converted to their compatible integer
571 types. The resulting type is unqualified and has no attributes.
572
573 This is the type for the result of most arithmetic operations
574 if the operands have the given two types. */
575
576static tree
577c_common_type (tree t1, tree t2)
578{
579 enum tree_code code1;
580 enum tree_code code2;
581
582 /* If one type is nonsense, use the other. */
583 if (t1 == error_mark_node)
584 return t2;
585 if (t2 == error_mark_node)
586 return t1;
587
588 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
589 t1 = TYPE_MAIN_VARIANT (t1);
590
591 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
592 t2 = TYPE_MAIN_VARIANT (t2);
593
594 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
595 t1 = build_type_attribute_variant (t1, NULL_TREE);
596
597 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
598 t2 = build_type_attribute_variant (t2, NULL_TREE);
599
600 /* Save time if the two types are the same. */
601
602 if (t1 == t2) return t1;
603
604 code1 = TREE_CODE (t1);
605 code2 = TREE_CODE (t2);
606
607 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
608 || code1 == REAL_TYPE || code1 == INTEGER_TYPE);
609 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
610 || code2 == REAL_TYPE || code2 == INTEGER_TYPE);
611
612 /* When one operand is a decimal float type, the other operand cannot be
613 a generic float type or a complex type. We also disallow vector types
614 here. */
615 if ((DECIMAL_FLOAT_TYPE_P (t1) || DECIMAL_FLOAT_TYPE_P (t2))
616 && !(DECIMAL_FLOAT_TYPE_P (t1) && DECIMAL_FLOAT_TYPE_P (t2)))
617 {
618 if (code1 == VECTOR_TYPE || code2 == VECTOR_TYPE)
619 {
620 error ("can%'t mix operands of decimal float and vector types");
621 return error_mark_node;
622 }
623 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
624 {
625 error ("can%'t mix operands of decimal float and complex types");
626 return error_mark_node;
627 }
628 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
629 {
630 error ("can%'t mix operands of decimal float and other float types");
631 return error_mark_node;
632 }
633 }
634
635 /* If one type is a vector type, return that type. (How the usual
636 arithmetic conversions apply to the vector types extension is not
637 precisely specified.) */
638 if (code1 == VECTOR_TYPE)
639 return t1;
640
641 if (code2 == VECTOR_TYPE)
642 return t2;
643
644 /* If one type is complex, form the common type of the non-complex
645 components, then make that complex. Use T1 or T2 if it is the
646 required type. */
647 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
648 {
649 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
650 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
651 tree subtype = c_common_type (subtype1, subtype2);
652
653 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
654 return t1;
655 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
656 return t2;
657 else
658 return build_complex_type (subtype);
659 }
660
661 /* If only one is real, use it as the result. */
662
663 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
664 return t1;
665
666 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
667 return t2;
668
669 /* If both are real and either are decimal floating point types, use
670 the decimal floating point type with the greater precision. */
671
672 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
673 {
674 if (TYPE_MAIN_VARIANT (t1) == dfloat128_type_node
675 || TYPE_MAIN_VARIANT (t2) == dfloat128_type_node)
676 return dfloat128_type_node;
677 else if (TYPE_MAIN_VARIANT (t1) == dfloat64_type_node
678 || TYPE_MAIN_VARIANT (t2) == dfloat64_type_node)
679 return dfloat64_type_node;
680 else if (TYPE_MAIN_VARIANT (t1) == dfloat32_type_node
681 || TYPE_MAIN_VARIANT (t2) == dfloat32_type_node)
682 return dfloat32_type_node;
683 }
684
685 /* Both real or both integers; use the one with greater precision. */
686
687 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
688 return t1;
689 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
690 return t2;
691
692 /* Same precision. Prefer long longs to longs to ints when the
693 same precision, following the C99 rules on integer type rank
694 (which are equivalent to the C90 rules for C90 types). */
695
696 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
697 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
698 return long_long_unsigned_type_node;
699
700 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
701 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
702 {
703 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
704 return long_long_unsigned_type_node;
705 else
706 return long_long_integer_type_node;
707 }
708
709 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
710 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
711 return long_unsigned_type_node;
712
713 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
714 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
715 {
716 /* But preserve unsignedness from the other type,
717 since long cannot hold all the values of an unsigned int. */
718 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
719 return long_unsigned_type_node;
720 else
721 return long_integer_type_node;
722 }
723
724 /* Likewise, prefer long double to double even if same size. */
725 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
726 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
727 return long_double_type_node;
728
729 /* Otherwise prefer the unsigned one. */
730
731 if (TYPE_UNSIGNED (t1))
732 return t1;
733 else
734 return t2;
735}
736
737/* Wrapper around c_common_type that is used by c-common.c and other
738 front end optimizations that remove promotions. ENUMERAL_TYPEs
739 are allowed here and are converted to their compatible integer types.
740 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
741 preferably a non-Boolean type as the common type. */
742tree
743common_type (tree t1, tree t2)
744{
745 if (TREE_CODE (t1) == ENUMERAL_TYPE)
746 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
747 if (TREE_CODE (t2) == ENUMERAL_TYPE)
748 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
749
750 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
751 if (TREE_CODE (t1) == BOOLEAN_TYPE
752 && TREE_CODE (t2) == BOOLEAN_TYPE)
753 return boolean_type_node;
754
755 /* If either type is BOOLEAN_TYPE, then return the other. */
756 if (TREE_CODE (t1) == BOOLEAN_TYPE)
757 return t2;
758 if (TREE_CODE (t2) == BOOLEAN_TYPE)
759 return t1;
760
761 return c_common_type (t1, t2);
762}
763
764/* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
765 or various other operations. Return 2 if they are compatible
766 but a warning may be needed if you use them together. */
767
768int
769comptypes (tree type1, tree type2)
770{
771 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base;
772 int val;
773
774 val = comptypes_internal (type1, type2);
775 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1);
776
777 return val;
778}
779
780/* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
781 or various other operations. Return 2 if they are compatible
782 but a warning may be needed if you use them together. This
783 differs from comptypes, in that we don't free the seen types. */
784
785static int
786comptypes_internal (tree type1, tree type2)
787{
788 tree t1 = type1;
789 tree t2 = type2;
790 int attrval, val;
791
792 /* Suppress errors caused by previously reported errors. */
793
794 if (t1 == t2 || !t1 || !t2
795 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
796 return 1;
797
798 /* If either type is the internal version of sizetype, return the
799 language version. */
800 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
801 && TYPE_ORIG_SIZE_TYPE (t1))
802 t1 = TYPE_ORIG_SIZE_TYPE (t1);
803
804 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
805 && TYPE_ORIG_SIZE_TYPE (t2))
806 t2 = TYPE_ORIG_SIZE_TYPE (t2);
807
808
809 /* Enumerated types are compatible with integer types, but this is
810 not transitive: two enumerated types in the same translation unit
811 are compatible with each other only if they are the same type. */
812
813 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
814 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
815 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
816 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
817
818 if (t1 == t2)
819 return 1;
820
821 /* Different classes of types can't be compatible. */
822
823 if (TREE_CODE (t1) != TREE_CODE (t2))
824 return 0;
825
826 /* Qualifiers must match. C99 6.7.3p9 */
827
828 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
829 return 0;
830
831 /* Allow for two different type nodes which have essentially the same
832 definition. Note that we already checked for equality of the type
833 qualifiers (just above). */
834
835 if (TREE_CODE (t1) != ARRAY_TYPE
836 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
837 return 1;
838
839 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
840 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
841 return 0;
842
843 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
844 val = 0;
845
846 switch (TREE_CODE (t1))
847 {
848 case POINTER_TYPE:
849 /* Do not remove mode or aliasing information. */
850 if (TYPE_MODE (t1) != TYPE_MODE (t2)
851 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
852 break;
853 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
854 ? 1 : comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2)));
855 break;
856
857 case FUNCTION_TYPE:
858 val = function_types_compatible_p (t1, t2);
859 break;
860
861 case ARRAY_TYPE:
862 {
863 tree d1 = TYPE_DOMAIN (t1);
864 tree d2 = TYPE_DOMAIN (t2);
865 bool d1_variable, d2_variable;
866 bool d1_zero, d2_zero;
867 val = 1;
868
869 /* Target types must match incl. qualifiers. */
870 if (TREE_TYPE (t1) != TREE_TYPE (t2)
871 && 0 == (val = comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2))))
872 return 0;
873
874 /* Sizes must match unless one is missing or variable. */
875 if (d1 == 0 || d2 == 0 || d1 == d2)
876 break;
877
878 d1_zero = !TYPE_MAX_VALUE (d1);
879 d2_zero = !TYPE_MAX_VALUE (d2);
880
881 d1_variable = (!d1_zero
882 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
883 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
884 d2_variable = (!d2_zero
885 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
886 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
887 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
888 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
889
890 if (d1_variable || d2_variable)
891 break;
892 if (d1_zero && d2_zero)
893 break;
894 if (d1_zero || d2_zero
895 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
896 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
897 val = 0;
898
899 break;
900 }
901
902 case ENUMERAL_TYPE:
903 case RECORD_TYPE:
904 case UNION_TYPE:
905 if (val != 1 && !same_translation_unit_p (t1, t2))
906 {
907 tree a1 = TYPE_ATTRIBUTES (t1);
908 tree a2 = TYPE_ATTRIBUTES (t2);
909
910 if (! attribute_list_contained (a1, a2)
911 && ! attribute_list_contained (a2, a1))
912 break;
913
914 if (attrval != 2)
915 return tagged_types_tu_compatible_p (t1, t2);
916 val = tagged_types_tu_compatible_p (t1, t2);
917 }
918 break;
919
920 case VECTOR_TYPE:
921 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
922 && comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2));
923 break;
924
925 default:
926 break;
927 }
928 return attrval == 2 && val == 1 ? 2 : val;
929}
930
931/* Return 1 if TTL and TTR are pointers to types that are equivalent,
932 ignoring their qualifiers. */
933
934static int
935comp_target_types (tree ttl, tree ttr)
936{
937 int val;
938 tree mvl, mvr;
939
940 /* Do not lose qualifiers on element types of array types that are
941 pointer targets by taking their TYPE_MAIN_VARIANT. */
942 mvl = TREE_TYPE (ttl);
943 mvr = TREE_TYPE (ttr);
944 if (TREE_CODE (mvl) != ARRAY_TYPE)
945 mvl = TYPE_MAIN_VARIANT (mvl);
946 if (TREE_CODE (mvr) != ARRAY_TYPE)
947 mvr = TYPE_MAIN_VARIANT (mvr);
948 val = comptypes (mvl, mvr);
949
950 if (val == 2 && pedantic)
951 pedwarn ("types are not quite compatible");
952 return val;
953}
954
955/* Subroutines of `comptypes'. */
956
957/* Determine whether two trees derive from the same translation unit.
958 If the CONTEXT chain ends in a null, that tree's context is still
959 being parsed, so if two trees have context chains ending in null,
960 they're in the same translation unit. */
961int
962same_translation_unit_p (tree t1, tree t2)
963{
964 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
965 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
966 {
967 case tcc_declaration:
968 t1 = DECL_CONTEXT (t1); break;
969 case tcc_type:
970 t1 = TYPE_CONTEXT (t1); break;
971 case tcc_exceptional:
972 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
973 default: gcc_unreachable ();
974 }
975
976 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
977 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
978 {
979 case tcc_declaration:
980 t2 = DECL_CONTEXT (t2); break;
981 case tcc_type:
982 t2 = TYPE_CONTEXT (t2); break;
983 case tcc_exceptional:
984 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
985 default: gcc_unreachable ();
986 }
987
988 return t1 == t2;
989}
990
991/* Allocate the seen two types, assuming that they are compatible. */
992
993static struct tagged_tu_seen_cache *
994alloc_tagged_tu_seen_cache (tree t1, tree t2)
995{
996 struct tagged_tu_seen_cache *tu = XNEW (struct tagged_tu_seen_cache);
997 tu->next = tagged_tu_seen_base;
998 tu->t1 = t1;
999 tu->t2 = t2;
1000
1001 tagged_tu_seen_base = tu;
1002
1003 /* The C standard says that two structures in different translation
1004 units are compatible with each other only if the types of their
1005 fields are compatible (among other things). We assume that they
1006 are compatible until proven otherwise when building the cache.
1007 An example where this can occur is:
1008 struct a
1009 {
1010 struct a *next;
1011 };
1012 If we are comparing this against a similar struct in another TU,
1013 and did not assume they were compatible, we end up with an infinite
1014 loop. */
1015 tu->val = 1;
1016 return tu;
1017}
1018
1019/* Free the seen types until we get to TU_TIL. */
1020
1021static void
1022free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *tu_til)
1023{
1024 const struct tagged_tu_seen_cache *tu = tagged_tu_seen_base;
1025 while (tu != tu_til)
1026 {
1027 struct tagged_tu_seen_cache *tu1 = (struct tagged_tu_seen_cache*)tu;
1028 tu = tu1->next;
1029 free (tu1);
1030 }
1031 tagged_tu_seen_base = tu_til;
1032}
1033
1034/* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
1035 compatible. If the two types are not the same (which has been
1036 checked earlier), this can only happen when multiple translation
1037 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
1038 rules. */
1039
1040static int
1041tagged_types_tu_compatible_p (tree t1, tree t2)
1042{
1043 tree s1, s2;
1044 bool needs_warning = false;
1045
1046 /* We have to verify that the tags of the types are the same. This
1047 is harder than it looks because this may be a typedef, so we have
1048 to go look at the original type. It may even be a typedef of a
1049 typedef...
1050 In the case of compiler-created builtin structs the TYPE_DECL
1051 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
1052 while (TYPE_NAME (t1)
1053 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
1054 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
1055 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
1056
1057 while (TYPE_NAME (t2)
1058 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
1059 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
1060 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
1061
1062 /* C90 didn't have the requirement that the two tags be the same. */
1063 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
1064 return 0;
1065
1066 /* C90 didn't say what happened if one or both of the types were
1067 incomplete; we choose to follow C99 rules here, which is that they
1068 are compatible. */
1069 if (TYPE_SIZE (t1) == NULL
1070 || TYPE_SIZE (t2) == NULL)
1071 return 1;
1072
1073 {
1074 const struct tagged_tu_seen_cache * tts_i;
1075 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
1076 if (tts_i->t1 == t1 && tts_i->t2 == t2)
1077 return tts_i->val;
1078 }
1079
1080 switch (TREE_CODE (t1))
1081 {
1082 case ENUMERAL_TYPE:
1083 {
1084 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1085 /* Speed up the case where the type values are in the same order. */
1086 tree tv1 = TYPE_VALUES (t1);
1087 tree tv2 = TYPE_VALUES (t2);
1088
1089 if (tv1 == tv2)
1090 {
1091 return 1;
1092 }
1093
1094 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
1095 {
1096 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
1097 break;
1098 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
1099 {
1100 tu->val = 0;
1101 return 0;
1102 }
1103 }
1104
1105 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
1106 {
1107 return 1;
1108 }
1109 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
1110 {
1111 tu->val = 0;
1112 return 0;
1113 }
1114
1115 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
1116 {
1117 tu->val = 0;
1118 return 0;
1119 }
1120
1121 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
1122 {
1123 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
1124 if (s2 == NULL
1125 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
1126 {
1127 tu->val = 0;
1128 return 0;
1129 }
1130 }
1131 return 1;
1132 }
1133
1134 case UNION_TYPE:
1135 {
1136 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1137 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
1138 {
1139 tu->val = 0;
1140 return 0;
1141 }
1142
1143 /* Speed up the common case where the fields are in the same order. */
1144 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2;
1145 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1146 {
1147 int result;
1148
1149
1150 if (DECL_NAME (s1) == NULL
1151 || DECL_NAME (s1) != DECL_NAME (s2))
1152 break;
1153 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1154 if (result == 0)
1155 {
1156 tu->val = 0;
1157 return 0;
1158 }
1159 if (result == 2)
1160 needs_warning = true;
1161
1162 if (TREE_CODE (s1) == FIELD_DECL
1163 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1164 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1165 {
1166 tu->val = 0;
1167 return 0;
1168 }
1169 }
1170 if (!s1 && !s2)
1171 {
1172 tu->val = needs_warning ? 2 : 1;
1173 return tu->val;
1174 }
1175
1176 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
1177 {
1178 bool ok = false;
1179
1180 if (DECL_NAME (s1) != NULL)
1181 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
1182 if (DECL_NAME (s1) == DECL_NAME (s2))
1183 {
1184 int result;
1185 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1186 if (result == 0)
1187 {
1188 tu->val = 0;
1189 return 0;
1190 }
1191 if (result == 2)
1192 needs_warning = true;
1193
1194 if (TREE_CODE (s1) == FIELD_DECL
1195 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1196 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1197 break;
1198
1199 ok = true;
1200 break;
1201 }
1202 if (!ok)
1203 {
1204 tu->val = 0;
1205 return 0;
1206 }
1207 }
1208 tu->val = needs_warning ? 2 : 10;
1209 return tu->val;
1210 }
1211
1212 case RECORD_TYPE:
1213 {
1214 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1215
1216 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
1217 s1 && s2;
1218 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1219 {
1220 int result;
1221 if (TREE_CODE (s1) != TREE_CODE (s2)
1222 || DECL_NAME (s1) != DECL_NAME (s2))
1223 break;
1224 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1225 if (result == 0)
1226 break;
1227 if (result == 2)
1228 needs_warning = true;
1229
1230 if (TREE_CODE (s1) == FIELD_DECL
1231 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1232 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1233 break;
1234 }
1235 if (s1 && s2)
1236 tu->val = 0;
1237 else
1238 tu->val = needs_warning ? 2 : 1;
1239 return tu->val;
1240 }
1241
1242 default:
1243 gcc_unreachable ();
1244 }
1245}
1246
1247/* Return 1 if two function types F1 and F2 are compatible.
1248 If either type specifies no argument types,
1249 the other must specify a fixed number of self-promoting arg types.
1250 Otherwise, if one type specifies only the number of arguments,
1251 the other must specify that number of self-promoting arg types.
1252 Otherwise, the argument types must match. */
1253
1254static int
1255function_types_compatible_p (tree f1, tree f2)
1256{
1257 tree args1, args2;
1258 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1259 int val = 1;
1260 int val1;
1261 tree ret1, ret2;
1262
1263 ret1 = TREE_TYPE (f1);
1264 ret2 = TREE_TYPE (f2);
1265
1266 /* 'volatile' qualifiers on a function's return type used to mean
1267 the function is noreturn. */
1268 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1269 pedwarn ("function return types not compatible due to %<volatile%>");
1270 if (TYPE_VOLATILE (ret1))
1271 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1272 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1273 if (TYPE_VOLATILE (ret2))
1274 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1275 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1276 val = comptypes_internal (ret1, ret2);
1277 if (val == 0)
1278 return 0;
1279
1280 args1 = TYPE_ARG_TYPES (f1);
1281 args2 = TYPE_ARG_TYPES (f2);
1282
1283 /* An unspecified parmlist matches any specified parmlist
1284 whose argument types don't need default promotions. */
1285
1286 if (args1 == 0)
1287 {
1288 if (!self_promoting_args_p (args2))
1289 return 0;
1290 /* If one of these types comes from a non-prototype fn definition,
1291 compare that with the other type's arglist.
1292 If they don't match, ask for a warning (but no error). */
1293 if (TYPE_ACTUAL_ARG_TYPES (f1)
1294 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
1295 val = 2;
1296 return val;
1297 }
1298 if (args2 == 0)
1299 {
1300 if (!self_promoting_args_p (args1))
1301 return 0;
1302 if (TYPE_ACTUAL_ARG_TYPES (f2)
1303 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
1304 val = 2;
1305 return val;
1306 }
1307
1308 /* Both types have argument lists: compare them and propagate results. */
1309 val1 = type_lists_compatible_p (args1, args2);
1310 return val1 != 1 ? val1 : val;
1311}
1312
1313/* Check two lists of types for compatibility,
1314 returning 0 for incompatible, 1 for compatible,
1315 or 2 for compatible with warning. */
1316
1317static int
1318type_lists_compatible_p (tree args1, tree args2)
1319{
1320 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1321 int val = 1;
1322 int newval = 0;
1323
1324 while (1)
1325 {
1326 tree a1, mv1, a2, mv2;
1327 if (args1 == 0 && args2 == 0)
1328 return val;
1329 /* If one list is shorter than the other,
1330 they fail to match. */
1331 if (args1 == 0 || args2 == 0)
1332 return 0;
1333 mv1 = a1 = TREE_VALUE (args1);
1334 mv2 = a2 = TREE_VALUE (args2);
1335 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1336 mv1 = TYPE_MAIN_VARIANT (mv1);
1337 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1338 mv2 = TYPE_MAIN_VARIANT (mv2);
1339 /* A null pointer instead of a type
1340 means there is supposed to be an argument
1341 but nothing is specified about what type it has.
1342 So match anything that self-promotes. */
1343 if (a1 == 0)
1344 {
1345 if (c_type_promotes_to (a2) != a2)
1346 return 0;
1347 }
1348 else if (a2 == 0)
1349 {
1350 if (c_type_promotes_to (a1) != a1)
1351 return 0;
1352 }
1353 /* If one of the lists has an error marker, ignore this arg. */
1354 else if (TREE_CODE (a1) == ERROR_MARK
1355 || TREE_CODE (a2) == ERROR_MARK)
1356 ;
1357 else if (!(newval = comptypes_internal (mv1, mv2)))
1358 {
1359 /* Allow wait (union {union wait *u; int *i} *)
1360 and wait (union wait *) to be compatible. */
1361 if (TREE_CODE (a1) == UNION_TYPE
1362 && (TYPE_NAME (a1) == 0
1363 || TYPE_TRANSPARENT_UNION (a1))
1364 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1365 && tree_int_cst_equal (TYPE_SIZE (a1),
1366 TYPE_SIZE (a2)))
1367 {
1368 tree memb;
1369 for (memb = TYPE_FIELDS (a1);
1370 memb; memb = TREE_CHAIN (memb))
1371 {
1372 tree mv3 = TREE_TYPE (memb);
1373 if (mv3 && mv3 != error_mark_node
1374 && TREE_CODE (mv3) != ARRAY_TYPE)
1375 mv3 = TYPE_MAIN_VARIANT (mv3);
1376 if (comptypes_internal (mv3, mv2))
1377 break;
1378 }
1379 if (memb == 0)
1380 return 0;
1381 }
1382 else if (TREE_CODE (a2) == UNION_TYPE
1383 && (TYPE_NAME (a2) == 0
1384 || TYPE_TRANSPARENT_UNION (a2))
1385 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1386 && tree_int_cst_equal (TYPE_SIZE (a2),
1387 TYPE_SIZE (a1)))
1388 {
1389 tree memb;
1390 for (memb = TYPE_FIELDS (a2);
1391 memb; memb = TREE_CHAIN (memb))
1392 {
1393 tree mv3 = TREE_TYPE (memb);
1394 if (mv3 && mv3 != error_mark_node
1395 && TREE_CODE (mv3) != ARRAY_TYPE)
1396 mv3 = TYPE_MAIN_VARIANT (mv3);
1397 if (comptypes_internal (mv3, mv1))
1398 break;
1399 }
1400 if (memb == 0)
1401 return 0;
1402 }
1403 else
1404 return 0;
1405 }
1406
1407 /* comptypes said ok, but record if it said to warn. */
1408 if (newval > val)
1409 val = newval;
1410
1411 args1 = TREE_CHAIN (args1);
1412 args2 = TREE_CHAIN (args2);
1413 }
1414}
1415
1416/* Compute the size to increment a pointer by. */
1417
1418static tree
1419c_size_in_bytes (tree type)
1420{
1421 enum tree_code code = TREE_CODE (type);
1422
1423 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1424 return size_one_node;
1425
1426 if (!COMPLETE_OR_VOID_TYPE_P (type))
1427 {
1428 error ("arithmetic on pointer to an incomplete type");
1429 return size_one_node;
1430 }
1431
1432 /* Convert in case a char is more than one unit. */
1433 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1434 size_int (TYPE_PRECISION (char_type_node)
1435 / BITS_PER_UNIT));
1436}
1437
1438/* Return either DECL or its known constant value (if it has one). */
1439
1440tree
1441decl_constant_value (tree decl)
1442{
1443 if (/* Don't change a variable array bound or initial value to a constant
1444 in a place where a variable is invalid. Note that DECL_INITIAL
1445 isn't valid for a PARM_DECL. */
1446 current_function_decl != 0
1447 && TREE_CODE (decl) != PARM_DECL
1448 && !TREE_THIS_VOLATILE (decl)
1449 && TREE_READONLY (decl)
1450 && DECL_INITIAL (decl) != 0
1451 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1452 /* This is invalid if initial value is not constant.
1453 If it has either a function call, a memory reference,
1454 or a variable, then re-evaluating it could give different results. */
1455 && TREE_CONSTANT (DECL_INITIAL (decl))
1456 /* Check for cases where this is sub-optimal, even though valid. */
1457 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1458 return DECL_INITIAL (decl);
1459 return decl;
1460}
1461
1462/* Return either DECL or its known constant value (if it has one), but
1463 return DECL if pedantic or DECL has mode BLKmode. This is for
1464 bug-compatibility with the old behavior of decl_constant_value
1465 (before GCC 3.0); every use of this function is a bug and it should
1466 be removed before GCC 3.1. It is not appropriate to use pedantic
1467 in a way that affects optimization, and BLKmode is probably not the
1468 right test for avoiding misoptimizations either. */
1469
1470static tree
1471decl_constant_value_for_broken_optimization (tree decl)
1472{
1473 tree ret;
1474
1475 if (pedantic || DECL_MODE (decl) == BLKmode)
1476 return decl;
1477
1478 ret = decl_constant_value (decl);
1479 /* Avoid unwanted tree sharing between the initializer and current
1480 function's body where the tree can be modified e.g. by the
1481 gimplifier. */
1482 if (ret != decl && TREE_STATIC (decl))
1483 ret = unshare_expr (ret);
1484 return ret;
1485}
1486
1487/* Convert the array expression EXP to a pointer. */
1488static tree
1489array_to_pointer_conversion (tree exp)
1490{
1491 tree orig_exp = exp;
1492 tree type = TREE_TYPE (exp);
1493 tree adr;
1494 tree restype = TREE_TYPE (type);
1495 tree ptrtype;
1496
1497 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
1498
1499 STRIP_TYPE_NOPS (exp);
1500
1501 if (TREE_NO_WARNING (orig_exp))
1502 TREE_NO_WARNING (exp) = 1;
1503
1504 ptrtype = build_pointer_type (restype);
1505
1506 if (TREE_CODE (exp) == INDIRECT_REF)
1507 return convert (ptrtype, TREE_OPERAND (exp, 0));
1508
1509 if (TREE_CODE (exp) == VAR_DECL)
1510 {
1511 /* We are making an ADDR_EXPR of ptrtype. This is a valid
1512 ADDR_EXPR because it's the best way of representing what
1513 happens in C when we take the address of an array and place
1514 it in a pointer to the element type. */
1515 adr = build1 (ADDR_EXPR, ptrtype, exp);
1516 if (!c_mark_addressable (exp))
1517 return error_mark_node;
1518 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1519 return adr;
1520 }
1521
1522 /* This way is better for a COMPONENT_REF since it can
1523 simplify the offset for a component. */
1524 adr = build_unary_op (ADDR_EXPR, exp, 1);
1525 return convert (ptrtype, adr);
1526}
1527
1528/* Convert the function expression EXP to a pointer. */
1529static tree
1530function_to_pointer_conversion (tree exp)
1531{
1532 tree orig_exp = exp;
1533
1534 gcc_assert (TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE);
1535
1536 STRIP_TYPE_NOPS (exp);
1537
1538 if (TREE_NO_WARNING (orig_exp))
1539 TREE_NO_WARNING (exp) = 1;
1540
1541 return build_unary_op (ADDR_EXPR, exp, 0);
1542}
1543
1544/* Perform the default conversion of arrays and functions to pointers.
1545 Return the result of converting EXP. For any other expression, just
1546 return EXP after removing NOPs. */
1547
1548struct c_expr
1549default_function_array_conversion (struct c_expr exp)
1550{
1551 tree orig_exp = exp.value;
1552 tree type = TREE_TYPE (exp.value);
1553 enum tree_code code = TREE_CODE (type);
1554
1555 switch (code)
1556 {
1557 case ARRAY_TYPE:
1558 {
1559 bool not_lvalue = false;
1560 bool lvalue_array_p;
1561
1562 while ((TREE_CODE (exp.value) == NON_LVALUE_EXPR
1563 || TREE_CODE (exp.value) == NOP_EXPR
1564 || TREE_CODE (exp.value) == CONVERT_EXPR)
1565 && TREE_TYPE (TREE_OPERAND (exp.value, 0)) == type)
1566 {
1567 if (TREE_CODE (exp.value) == NON_LVALUE_EXPR)
1568 not_lvalue = true;
1569 exp.value = TREE_OPERAND (exp.value, 0);
1570 }
1571
1572 if (TREE_NO_WARNING (orig_exp))
1573 TREE_NO_WARNING (exp.value) = 1;
1574
1575 lvalue_array_p = !not_lvalue && lvalue_p (exp.value);
1576 if (!flag_isoc99 && !lvalue_array_p)
1577 {
1578 /* Before C99, non-lvalue arrays do not decay to pointers.
1579 Normally, using such an array would be invalid; but it can
1580 be used correctly inside sizeof or as a statement expression.
1581 Thus, do not give an error here; an error will result later. */
1582 return exp;
1583 }
1584
1585 exp.value = array_to_pointer_conversion (exp.value);
1586 }
1587 break;
1588 case FUNCTION_TYPE:
1589 exp.value = function_to_pointer_conversion (exp.value);
1590 break;
1591 default:
1592 STRIP_TYPE_NOPS (exp.value);
1593 if (TREE_NO_WARNING (orig_exp))
1594 TREE_NO_WARNING (exp.value) = 1;
1595 break;
1596 }
1597
1598 return exp;
1599}
1600
1601
1602/* EXP is an expression of integer type. Apply the integer promotions
1603 to it and return the promoted value. */
1604
1605tree
1606perform_integral_promotions (tree exp)
1607{
1608 tree type = TREE_TYPE (exp);
1609 enum tree_code code = TREE_CODE (type);
1610
1611 gcc_assert (INTEGRAL_TYPE_P (type));
1612
1613 /* Normally convert enums to int,
1614 but convert wide enums to something wider. */
1615 if (code == ENUMERAL_TYPE)
1616 {
1617 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1618 TYPE_PRECISION (integer_type_node)),
1619 ((TYPE_PRECISION (type)
1620 >= TYPE_PRECISION (integer_type_node))
1621 && TYPE_UNSIGNED (type)));
1622
1623 return convert (type, exp);
1624 }
1625
1626 /* ??? This should no longer be needed now bit-fields have their
1627 proper types. */
1628 if (TREE_CODE (exp) == COMPONENT_REF
1629 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1630 /* If it's thinner than an int, promote it like a
1631 c_promoting_integer_type_p, otherwise leave it alone. */
1632 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1633 TYPE_PRECISION (integer_type_node)))
1634 return convert (integer_type_node, exp);
1635
1636 if (c_promoting_integer_type_p (type))
1637 {
1638 /* Preserve unsignedness if not really getting any wider. */
1639 if (TYPE_UNSIGNED (type)
1640 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1641 return convert (unsigned_type_node, exp);
1642
1643 return convert (integer_type_node, exp);
1644 }
1645
1646 return exp;
1647}
1648
1649
1650/* Perform default promotions for C data used in expressions.
1651 Enumeral types or short or char are converted to int.
1652 In addition, manifest constants symbols are replaced by their values. */
1653
1654tree
1655default_conversion (tree exp)
1656{
1657 tree orig_exp;
1658 tree type = TREE_TYPE (exp);
1659 enum tree_code code = TREE_CODE (type);
1660
1661 /* Functions and arrays have been converted during parsing. */
1662 gcc_assert (code != FUNCTION_TYPE);
1663 if (code == ARRAY_TYPE)
1664 return exp;
1665
1666 /* Constants can be used directly unless they're not loadable. */
1667 if (TREE_CODE (exp) == CONST_DECL)
1668 exp = DECL_INITIAL (exp);
1669
1670 /* Replace a nonvolatile const static variable with its value unless
1671 it is an array, in which case we must be sure that taking the
1672 address of the array produces consistent results. */
1673 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1674 {
1675 exp = decl_constant_value_for_broken_optimization (exp);
1676 type = TREE_TYPE (exp);
1677 }
1678
1679 /* Strip no-op conversions. */
1680 orig_exp = exp;
1681 STRIP_TYPE_NOPS (exp);
1682
1683 if (TREE_NO_WARNING (orig_exp))
1684 TREE_NO_WARNING (exp) = 1;
1685
1686 if (INTEGRAL_TYPE_P (type))
1687 return perform_integral_promotions (exp);
1688
1689 if (code == VOID_TYPE)
1690 {
1691 error ("void value not ignored as it ought to be");
1692 return error_mark_node;
1693 }
1694 return exp;
1695}
1696
1697/* Look up COMPONENT in a structure or union DECL.
1698
1699 If the component name is not found, returns NULL_TREE. Otherwise,
1700 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1701 stepping down the chain to the component, which is in the last
1702 TREE_VALUE of the list. Normally the list is of length one, but if
1703 the component is embedded within (nested) anonymous structures or
1704 unions, the list steps down the chain to the component. */
1705
1706static tree
1707lookup_field (tree decl, tree component)
1708{
1709 tree type = TREE_TYPE (decl);
1710 tree field;
1711
1712 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1713 to the field elements. Use a binary search on this array to quickly
1714 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1715 will always be set for structures which have many elements. */
1716
1717 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1718 {
1719 int bot, top, half;
1720 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1721
1722 field = TYPE_FIELDS (type);
1723 bot = 0;
1724 top = TYPE_LANG_SPECIFIC (type)->s->len;
1725 while (top - bot > 1)
1726 {
1727 half = (top - bot + 1) >> 1;
1728 field = field_array[bot+half];
1729
1730 if (DECL_NAME (field) == NULL_TREE)
1731 {
1732 /* Step through all anon unions in linear fashion. */
1733 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1734 {
1735 field = field_array[bot++];
1736 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1737 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1738 {
1739 tree anon = lookup_field (field, component);
1740
1741 if (anon)
1742 return tree_cons (NULL_TREE, field, anon);
1743 }
1744 }
1745
1746 /* Entire record is only anon unions. */
1747 if (bot > top)
1748 return NULL_TREE;
1749
1750 /* Restart the binary search, with new lower bound. */
1751 continue;
1752 }
1753
1754 if (DECL_NAME (field) == component)
1755 break;
1756 if (DECL_NAME (field) < component)
1757 bot += half;
1758 else
1759 top = bot + half;
1760 }
1761
1762 if (DECL_NAME (field_array[bot]) == component)
1763 field = field_array[bot];
1764 else if (DECL_NAME (field) != component)
1765 return NULL_TREE;
1766 }
1767 else
1768 {
1769 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1770 {
1771 if (DECL_NAME (field) == NULL_TREE
1772 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1773 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1774 {
1775 tree anon = lookup_field (field, component);
1776
1777 if (anon)
1778 return tree_cons (NULL_TREE, field, anon);
1779 }
1780
1781 if (DECL_NAME (field) == component)
1782 break;
1783 }
1784
1785 if (field == NULL_TREE)
1786 return NULL_TREE;
1787 }
1788
1789 return tree_cons (NULL_TREE, field, NULL_TREE);
1790}
1791
1792/* Make an expression to refer to the COMPONENT field of
1793 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1794
1795tree
1796build_component_ref (tree datum, tree component)
1797{
1798 tree type = TREE_TYPE (datum);
1799 enum tree_code code = TREE_CODE (type);
1800 tree field = NULL;
1801 tree ref;
1802
1803 if (!objc_is_public (datum, component))
1804 return error_mark_node;
1805
1806 /* See if there is a field or component with name COMPONENT. */
1807
1808 if (code == RECORD_TYPE || code == UNION_TYPE)
1809 {
1810 if (!COMPLETE_TYPE_P (type))
1811 {
1812 c_incomplete_type_error (NULL_TREE, type);
1813 return error_mark_node;
1814 }
1815
1816 field = lookup_field (datum, component);
1817
1818 if (!field)
1819 {
1820 error ("%qT has no member named %qE", type, component);
1821 return error_mark_node;
1822 }
1823
1824 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1825 This might be better solved in future the way the C++ front
1826 end does it - by giving the anonymous entities each a
1827 separate name and type, and then have build_component_ref
1828 recursively call itself. We can't do that here. */
1829 do
1830 {
1831 tree subdatum = TREE_VALUE (field);
1832 int quals;
1833 tree subtype;
1834
1835 if (TREE_TYPE (subdatum) == error_mark_node)
1836 return error_mark_node;
1837
1838 quals = TYPE_QUALS (strip_array_types (TREE_TYPE (subdatum)));
1839 quals |= TYPE_QUALS (TREE_TYPE (datum));
1840 subtype = c_build_qualified_type (TREE_TYPE (subdatum), quals);
1841
1842 ref = build3 (COMPONENT_REF, subtype, datum, subdatum,
1843 NULL_TREE);
1844 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1845 TREE_READONLY (ref) = 1;
1846 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1847 TREE_THIS_VOLATILE (ref) = 1;
1848
1849 if (TREE_DEPRECATED (subdatum))
1850 warn_deprecated_use (subdatum);
1851
1852 datum = ref;
1853
1854 field = TREE_CHAIN (field);
1855 }
1856 while (field);
1857
1858 return ref;
1859 }
1860 else if (code != ERROR_MARK)
1861 error ("request for member %qE in something not a structure or union",
1862 component);
1863
1864 return error_mark_node;
1865}
1866
1867/* Given an expression PTR for a pointer, return an expression
1868 for the value pointed to.
1869 ERRORSTRING is the name of the operator to appear in error messages. */
1870
1871tree
1872build_indirect_ref (tree ptr, const char *errorstring)
1873{
1874 tree pointer = default_conversion (ptr);
1875 tree type = TREE_TYPE (pointer);
1876
1877 if (TREE_CODE (type) == POINTER_TYPE)
1878 {
1879 if (TREE_CODE (pointer) == CONVERT_EXPR
1880 || TREE_CODE (pointer) == NOP_EXPR
1881 || TREE_CODE (pointer) == VIEW_CONVERT_EXPR)
1882 {
1883 /* If a warning is issued, mark it to avoid duplicates from
1884 the backend. This only needs to be done at
1885 warn_strict_aliasing > 2. */
1886 if (warn_strict_aliasing > 2)
1887 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (pointer, 0)),
1888 type, TREE_OPERAND (pointer, 0)))
1889 TREE_NO_WARNING (pointer) = 1;
1890 }
1891
1892 if (TREE_CODE (pointer) == ADDR_EXPR
1893 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1894 == TREE_TYPE (type)))
1895 return TREE_OPERAND (pointer, 0);
1896 else
1897 {
1898 tree t = TREE_TYPE (type);
1899 tree ref;
1900
1901 ref = build1 (INDIRECT_REF, t, pointer);
1902
1903 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1904 {
1905 error ("dereferencing pointer to incomplete type");
1906 return error_mark_node;
1907 }
1908 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1909 warning (0, "dereferencing %<void *%> pointer");
1910
1911 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1912 so that we get the proper error message if the result is used
1913 to assign to. Also, &* is supposed to be a no-op.
1914 And ANSI C seems to specify that the type of the result
1915 should be the const type. */
1916 /* A de-reference of a pointer to const is not a const. It is valid
1917 to change it via some other pointer. */
1918 TREE_READONLY (ref) = TYPE_READONLY (t);
1919 TREE_SIDE_EFFECTS (ref)
1920 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1921 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1922 return ref;
1923 }
1924 }
1925 else if (TREE_CODE (pointer) != ERROR_MARK)
1926 error ("invalid type argument of %qs (have %qT)", errorstring, type);
1927 return error_mark_node;
1928}
1929
1930/* This handles expressions of the form "a[i]", which denotes
1931 an array reference.
1932
1933 This is logically equivalent in C to *(a+i), but we may do it differently.
1934 If A is a variable or a member, we generate a primitive ARRAY_REF.
1935 This avoids forcing the array out of registers, and can work on
1936 arrays that are not lvalues (for example, members of structures returned
1937 by functions). */
1938
1939tree
1940build_array_ref (tree array, tree index)
1941{
1942 bool swapped = false;
1943 if (TREE_TYPE (array) == error_mark_node
1944 || TREE_TYPE (index) == error_mark_node)
1945 return error_mark_node;
1946
1947 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
1948 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
1949 {
1950 tree temp;
1951 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
1952 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
1953 {
1954 error ("subscripted value is neither array nor pointer");
1955 return error_mark_node;
1956 }
1957 temp = array;
1958 array = index;
1959 index = temp;
1960 swapped = true;
1961 }
1962
1963 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
1964 {
1965 error ("array subscript is not an integer");
1966 return error_mark_node;
1967 }
1968
1969 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
1970 {
1971 error ("subscripted value is pointer to function");
1972 return error_mark_node;
1973 }
1974
1975 /* ??? Existing practice has been to warn only when the char
1976 index is syntactically the index, not for char[array]. */
1977 if (!swapped)
1978 warn_array_subscript_with_type_char (index);
1979
1980 /* Apply default promotions *after* noticing character types. */
1981 index = default_conversion (index);
1982
1983 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
1984
1985 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1986 {
1987 tree rval, type;
1988
1989 /* An array that is indexed by a non-constant
1990 cannot be stored in a register; we must be able to do
1991 address arithmetic on its address.
1992 Likewise an array of elements of variable size. */
1993 if (TREE_CODE (index) != INTEGER_CST
1994 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1995 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1996 {
1997 if (!c_mark_addressable (array))
1998 return error_mark_node;
1999 }
2000 /* An array that is indexed by a constant value which is not within
2001 the array bounds cannot be stored in a register either; because we
2002 would get a crash in store_bit_field/extract_bit_field when trying
2003 to access a non-existent part of the register. */
2004 if (TREE_CODE (index) == INTEGER_CST
2005 && TYPE_DOMAIN (TREE_TYPE (array))
2006 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
2007 {
2008 if (!c_mark_addressable (array))
2009 return error_mark_node;
2010 }
2011
2012 if (pedantic)
2013 {
2014 tree foo = array;
2015 while (TREE_CODE (foo) == COMPONENT_REF)
2016 foo = TREE_OPERAND (foo, 0);
2017 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
2018 pedwarn ("ISO C forbids subscripting %<register%> array");
2019 else if (!flag_isoc99 && !lvalue_p (foo))
2020 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
2021 }
2022
2023 type = TREE_TYPE (TREE_TYPE (array));
2024 if (TREE_CODE (type) != ARRAY_TYPE)
2025 type = TYPE_MAIN_VARIANT (type);
2026 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
2027 /* Array ref is const/volatile if the array elements are
2028 or if the array is. */
2029 TREE_READONLY (rval)
2030 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
2031 | TREE_READONLY (array));
2032 TREE_SIDE_EFFECTS (rval)
2033 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2034 | TREE_SIDE_EFFECTS (array));
2035 TREE_THIS_VOLATILE (rval)
2036 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2037 /* This was added by rms on 16 Nov 91.
2038 It fixes vol struct foo *a; a->elts[1]
2039 in an inline function.
2040 Hope it doesn't break something else. */
2041 | TREE_THIS_VOLATILE (array));
2042 return require_complete_type (fold (rval));
2043 }
2044 else
2045 {
2046 tree ar = default_conversion (array);
2047
2048 if (ar == error_mark_node)
2049 return ar;
2050
2051 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
2052 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
2053
2054 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
2055 "array indexing");
2056 }
2057}
2058
2059/* Build an external reference to identifier ID. FUN indicates
2060 whether this will be used for a function call. LOC is the source
2061 location of the identifier. */
2062tree
2063build_external_ref (tree id, int fun, location_t loc)
2064{
2065 tree ref;
2066 tree decl = lookup_name (id);
2067
2068 /* In Objective-C, an instance variable (ivar) may be preferred to
2069 whatever lookup_name() found. */
2070 decl = objc_lookup_ivar (decl, id);
2071
2072 if (decl && decl != error_mark_node)
2073 ref = decl;
2074 else if (fun)
2075 /* Implicit function declaration. */
2076 ref = implicitly_declare (id);
2077 else if (decl == error_mark_node)
2078 /* Don't complain about something that's already been
2079 complained about. */
2080 return error_mark_node;
2081 else
2082 {
2083 undeclared_variable (id, loc);
2084 return error_mark_node;
2085 }
2086
2087 if (TREE_TYPE (ref) == error_mark_node)
2088 return error_mark_node;
2089
2090 if (TREE_DEPRECATED (ref))
2091 warn_deprecated_use (ref);
2092
2093 if (!skip_evaluation)
2094 assemble_external (ref);
2095 TREE_USED (ref) = 1;
2096
2097 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
2098 {
2099 if (!in_sizeof && !in_typeof)
2100 C_DECL_USED (ref) = 1;
2101 else if (DECL_INITIAL (ref) == 0
2102 && DECL_EXTERNAL (ref)
2103 && !TREE_PUBLIC (ref))
2104 record_maybe_used_decl (ref);
2105 }
2106
2107 if (TREE_CODE (ref) == CONST_DECL)
2108 {
2109 used_types_insert (TREE_TYPE (ref));
2110 ref = DECL_INITIAL (ref);
2111 TREE_CONSTANT (ref) = 1;
2112 TREE_INVARIANT (ref) = 1;
2113 }
2114 else if (current_function_decl != 0
2115 && !DECL_FILE_SCOPE_P (current_function_decl)
2116 && (TREE_CODE (ref) == VAR_DECL
2117 || TREE_CODE (ref) == PARM_DECL
2118 || TREE_CODE (ref) == FUNCTION_DECL))
2119 {
2120 tree context = decl_function_context (ref);
2121
2122 if (context != 0 && context != current_function_decl)
2123 DECL_NONLOCAL (ref) = 1;
2124 }
2125 /* C99 6.7.4p3: An inline definition of a function with external
2126 linkage ... shall not contain a reference to an identifier with
2127 internal linkage. */
2128 else if (current_function_decl != 0
2129 && DECL_DECLARED_INLINE_P (current_function_decl)
2130 && DECL_EXTERNAL (current_function_decl)
2131 && VAR_OR_FUNCTION_DECL_P (ref)
2132 && DECL_FILE_SCOPE_P (ref)
2133 && pedantic
2134 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref))
2135 && ! TREE_PUBLIC (ref))
2136 pedwarn ("%H%qD is static but used in inline function %qD "
2137 "which is not static", &loc, ref, current_function_decl);
2138
2139 return ref;
2140}
2141
2142/* Record details of decls possibly used inside sizeof or typeof. */
2143struct maybe_used_decl
2144{
2145 /* The decl. */
2146 tree decl;
2147 /* The level seen at (in_sizeof + in_typeof). */
2148 int level;
2149 /* The next one at this level or above, or NULL. */
2150 struct maybe_used_decl *next;
2151};
2152
2153static struct maybe_used_decl *maybe_used_decls;
2154
2155/* Record that DECL, an undefined static function reference seen
2156 inside sizeof or typeof, might be used if the operand of sizeof is
2157 a VLA type or the operand of typeof is a variably modified
2158 type. */
2159
2160static void
2161record_maybe_used_decl (tree decl)
2162{
2163 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
2164 t->decl = decl;
2165 t->level = in_sizeof + in_typeof;
2166 t->next = maybe_used_decls;
2167 maybe_used_decls = t;
2168}
2169
2170/* Pop the stack of decls possibly used inside sizeof or typeof. If
2171 USED is false, just discard them. If it is true, mark them used
2172 (if no longer inside sizeof or typeof) or move them to the next
2173 level up (if still inside sizeof or typeof). */
2174
2175void
2176pop_maybe_used (bool used)
2177{
2178 struct maybe_used_decl *p = maybe_used_decls;
2179 int cur_level = in_sizeof + in_typeof;
2180 while (p && p->level > cur_level)
2181 {
2182 if (used)
2183 {
2184 if (cur_level == 0)
2185 C_DECL_USED (p->decl) = 1;
2186 else
2187 p->level = cur_level;
2188 }
2189 p = p->next;
2190 }
2191 if (!used || cur_level == 0)
2192 maybe_used_decls = p;
2193}
2194
2195/* Return the result of sizeof applied to EXPR. */
2196
2197struct c_expr
2198c_expr_sizeof_expr (struct c_expr expr)
2199{
2200 struct c_expr ret;
2201 if (expr.value == error_mark_node)
2202 {
2203 ret.value = error_mark_node;
2204 ret.original_code = ERROR_MARK;
2205 pop_maybe_used (false);
2206 }
2207 else
2208 {
2209 ret.value = c_sizeof (TREE_TYPE (expr.value));
2210 ret.original_code = ERROR_MARK;
2211 if (c_vla_type_p (TREE_TYPE (expr.value)))
2212 {
2213 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */
2214 ret.value = build2 (COMPOUND_EXPR, TREE_TYPE (ret.value), expr.value, ret.value);
2215 }
2216 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
2217 }
2218 return ret;
2219}
2220
2221/* Return the result of sizeof applied to T, a structure for the type
2222 name passed to sizeof (rather than the type itself). */
2223
2224struct c_expr
2225c_expr_sizeof_type (struct c_type_name *t)
2226{
2227 tree type;
2228 struct c_expr ret;
2229 type = groktypename (t);
2230 ret.value = c_sizeof (type);
2231 ret.original_code = ERROR_MARK;
2232 pop_maybe_used (type != error_mark_node
2233 ? C_TYPE_VARIABLE_SIZE (type) : false);
2234 return ret;
2235}
2236
2237/* Build a function call to function FUNCTION with parameters PARAMS.
2238 PARAMS is a list--a chain of TREE_LIST nodes--in which the
2239 TREE_VALUE of each node is a parameter-expression.
2240 FUNCTION's data type may be a function type or a pointer-to-function. */
2241
2242tree
2243build_function_call (tree function, tree params)
2244{
2245 tree fntype, fundecl = 0;
2246 tree coerced_params;
2247 tree name = NULL_TREE, result;
2248 tree tem;
2249
2250 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2251 STRIP_TYPE_NOPS (function);
2252
2253 /* Convert anything with function type to a pointer-to-function. */
2254 if (TREE_CODE (function) == FUNCTION_DECL)
2255 {
2256 /* Implement type-directed function overloading for builtins.
2257 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
2258 handle all the type checking. The result is a complete expression
2259 that implements this function call. */
2260 tem = resolve_overloaded_builtin (function, params);
2261 if (tem)
2262 return tem;
2263
2264 name = DECL_NAME (function);
2265 fundecl = function;
2266 }
2267 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE)
2268 function = function_to_pointer_conversion (function);
2269
2270 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2271 expressions, like those used for ObjC messenger dispatches. */
2272 function = objc_rewrite_function_call (function, params);
2273
2274 fntype = TREE_TYPE (function);
2275
2276 if (TREE_CODE (fntype) == ERROR_MARK)
2277 return error_mark_node;
2278
2279 if (!(TREE_CODE (fntype) == POINTER_TYPE
2280 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2281 {
2282 error ("called object %qE is not a function", function);
2283 return error_mark_node;
2284 }
2285
2286 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2287 current_function_returns_abnormally = 1;
2288
2289 /* fntype now gets the type of function pointed to. */
2290 fntype = TREE_TYPE (fntype);
2291
2292 /* Check that the function is called through a compatible prototype.
2293 If it is not, replace the call by a trap, wrapped up in a compound
2294 expression if necessary. This has the nice side-effect to prevent
2295 the tree-inliner from generating invalid assignment trees which may
2296 blow up in the RTL expander later. */
2297 if ((TREE_CODE (function) == NOP_EXPR
2298 || TREE_CODE (function) == CONVERT_EXPR)
2299 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2300 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2301 && !comptypes (fntype, TREE_TYPE (tem)))
2302 {
2303 tree return_type = TREE_TYPE (fntype);
2304 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
2305 NULL_TREE);
2306
2307 /* This situation leads to run-time undefined behavior. We can't,
2308 therefore, simply error unless we can prove that all possible
2309 executions of the program must execute the code. */
2310 warning (0, "function called through a non-compatible type");
2311
2312 /* We can, however, treat "undefined" any way we please.
2313 Call abort to encourage the user to fix the program. */
2314 inform ("if this code is reached, the program will abort");
2315
2316 if (VOID_TYPE_P (return_type))
2317 return trap;
2318 else
2319 {
2320 tree rhs;
2321
2322 if (AGGREGATE_TYPE_P (return_type))
2323 rhs = build_compound_literal (return_type,
2324 build_constructor (return_type, 0));
2325 else
2326 rhs = fold_convert (return_type, integer_zero_node);
2327
2328 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
2329 }
2330 }
2331
2332 /* Convert the parameters to the types declared in the
2333 function prototype, or apply default promotions. */
2334
2335 coerced_params
2336 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl);
2337
2338 if (coerced_params == error_mark_node)
2339 return error_mark_node;
2340
2341 /* Check that the arguments to the function are valid. */
2342
2343 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2344 TYPE_ARG_TYPES (fntype));
2345
2346 if (require_constant_value)
2347 {
2348 result = fold_build3_initializer (CALL_EXPR, TREE_TYPE (fntype),
2349 function, coerced_params, NULL_TREE);
2350
2351 if (TREE_CONSTANT (result)
2352 && (name == NULL_TREE
2353 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
2354 pedwarn_init ("initializer element is not constant");
2355 }
2356 else
2357 result = fold_build3 (CALL_EXPR, TREE_TYPE (fntype),
2358 function, coerced_params, NULL_TREE);
2359
2360 if (VOID_TYPE_P (TREE_TYPE (result)))
2361 return result;
2362 return require_complete_type (result);
2363}
2364
2365/* Convert the argument expressions in the list VALUES
2366 to the types in the list TYPELIST. The result is a list of converted
2367 argument expressions, unless there are too few arguments in which
2368 case it is error_mark_node.
2369
2370 If TYPELIST is exhausted, or when an element has NULL as its type,
2371 perform the default conversions.
2372
2373 PARMLIST is the chain of parm decls for the function being called.
2374 It may be 0, if that info is not available.
2375 It is used only for generating error messages.
2376
2377 FUNCTION is a tree for the called function. It is used only for
2378 error messages, where it is formatted with %qE.
2379
2380 This is also where warnings about wrong number of args are generated.
2381
2382 Both VALUES and the returned value are chains of TREE_LIST nodes
2383 with the elements of the list in the TREE_VALUE slots of those nodes. */
2384
2385static tree
2386convert_arguments (tree typelist, tree values, tree function, tree fundecl)
2387{
2388 tree typetail, valtail;
2389 tree result = NULL;
2390 int parmnum;
2391 tree selector;
2392
2393 /* Change pointer to function to the function itself for
2394 diagnostics. */
2395 if (TREE_CODE (function) == ADDR_EXPR
2396 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2397 function = TREE_OPERAND (function, 0);
2398
2399 /* Handle an ObjC selector specially for diagnostics. */
2400 selector = objc_message_selector ();
2401
2402 /* Scan the given expressions and types, producing individual
2403 converted arguments and pushing them on RESULT in reverse order. */
2404
2405 for (valtail = values, typetail = typelist, parmnum = 0;
2406 valtail;
2407 valtail = TREE_CHAIN (valtail), parmnum++)
2408 {
2409 tree type = typetail ? TREE_VALUE (typetail) : 0;
2410 tree val = TREE_VALUE (valtail);
2411 tree rname = function;
2412 int argnum = parmnum + 1;
2413 const char *invalid_func_diag;
2414
2415 if (type == void_type_node)
2416 {
2417 error ("too many arguments to function %qE", function);
2418 break;
2419 }
2420
2421 if (selector && argnum > 2)
2422 {
2423 rname = selector;
2424 argnum -= 2;
2425 }
2426
2427 STRIP_TYPE_NOPS (val);
2428
2429 val = require_complete_type (val);
2430
2431 if (type != 0)
2432 {
2433 /* Formal parm type is specified by a function prototype. */
2434 tree parmval;
2435
2436 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2437 {
2438 error ("type of formal parameter %d is incomplete", parmnum + 1);
2439 parmval = val;
2440 }
2441 else
2442 {
2443 /* Optionally warn about conversions that
2444 differ from the default conversions. */
2445 if (warn_conversion || warn_traditional)
2446 {
2447 unsigned int formal_prec = TYPE_PRECISION (type);
2448
2449 if (INTEGRAL_TYPE_P (type)
2450 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2451 warning (0, "passing argument %d of %qE as integer "
2452 "rather than floating due to prototype",
2453 argnum, rname);
2454 if (INTEGRAL_TYPE_P (type)
2455 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2456 warning (0, "passing argument %d of %qE as integer "
2457 "rather than complex due to prototype",
2458 argnum, rname);
2459 else if (TREE_CODE (type) == COMPLEX_TYPE
2460 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2461 warning (0, "passing argument %d of %qE as complex "
2462 "rather than floating due to prototype",
2463 argnum, rname);
2464 else if (TREE_CODE (type) == REAL_TYPE
2465 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2466 warning (0, "passing argument %d of %qE as floating "
2467 "rather than integer due to prototype",
2468 argnum, rname);
2469 else if (TREE_CODE (type) == COMPLEX_TYPE
2470 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2471 warning (0, "passing argument %d of %qE as complex "
2472 "rather than integer due to prototype",
2473 argnum, rname);
2474 else if (TREE_CODE (type) == REAL_TYPE
2475 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2476 warning (0, "passing argument %d of %qE as floating "
2477 "rather than complex due to prototype",
2478 argnum, rname);
2479 /* ??? At some point, messages should be written about
2480 conversions between complex types, but that's too messy
2481 to do now. */
2482 else if (TREE_CODE (type) == REAL_TYPE
2483 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2484 {
2485 /* Warn if any argument is passed as `float',
2486 since without a prototype it would be `double'. */
2487 if (formal_prec == TYPE_PRECISION (float_type_node)
2488 && type != dfloat32_type_node)
2489 warning (0, "passing argument %d of %qE as %<float%> "
2490 "rather than %<double%> due to prototype",
2491 argnum, rname);
2492
2493 /* Warn if mismatch between argument and prototype
2494 for decimal float types. Warn of conversions with
2495 binary float types and of precision narrowing due to
2496 prototype. */
2497 else if (type != TREE_TYPE (val)
2498 && (type == dfloat32_type_node
2499 || type == dfloat64_type_node
2500 || type == dfloat128_type_node
2501 || TREE_TYPE (val) == dfloat32_type_node
2502 || TREE_TYPE (val) == dfloat64_type_node
2503 || TREE_TYPE (val) == dfloat128_type_node)
2504 && (formal_prec
2505 <= TYPE_PRECISION (TREE_TYPE (val))
2506 || (type == dfloat128_type_node
2507 && (TREE_TYPE (val)
2508 != dfloat64_type_node
2509 && (TREE_TYPE (val)
2510 != dfloat32_type_node)))
2511 || (type == dfloat64_type_node
2512 && (TREE_TYPE (val)
2513 != dfloat32_type_node))))
2514 warning (0, "passing argument %d of %qE as %qT "
2515 "rather than %qT due to prototype",
2516 argnum, rname, type, TREE_TYPE (val));
2517
2518 }
2519 /* Detect integer changing in width or signedness.
2520 These warnings are only activated with
2521 -Wconversion, not with -Wtraditional. */
2522 else if (warn_conversion && INTEGRAL_TYPE_P (type)
2523 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2524 {
2525 tree would_have_been = default_conversion (val);
2526 tree type1 = TREE_TYPE (would_have_been);
2527
2528 if (TREE_CODE (type) == ENUMERAL_TYPE
2529 && (TYPE_MAIN_VARIANT (type)
2530 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2531 /* No warning if function asks for enum
2532 and the actual arg is that enum type. */
2533 ;
2534 else if (formal_prec != TYPE_PRECISION (type1))
2535 warning (OPT_Wconversion, "passing argument %d of %qE "
2536 "with different width due to prototype",
2537 argnum, rname);
2538 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2539 ;
2540 /* Don't complain if the formal parameter type
2541 is an enum, because we can't tell now whether
2542 the value was an enum--even the same enum. */
2543 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2544 ;
2545 else if (TREE_CODE (val) == INTEGER_CST
2546 && int_fits_type_p (val, type))
2547 /* Change in signedness doesn't matter
2548 if a constant value is unaffected. */
2549 ;
2550 /* If the value is extended from a narrower
2551 unsigned type, it doesn't matter whether we
2552 pass it as signed or unsigned; the value
2553 certainly is the same either way. */
2554 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2555 && TYPE_UNSIGNED (TREE_TYPE (val)))
2556 ;
2557 else if (TYPE_UNSIGNED (type))
2558 warning (OPT_Wconversion, "passing argument %d of %qE "
2559 "as unsigned due to prototype",
2560 argnum, rname);
2561 else
2562 warning (OPT_Wconversion, "passing argument %d of %qE "
2563 "as signed due to prototype", argnum, rname);
2564 }
2565 }
2566
2567 parmval = convert_for_assignment (type, val, ic_argpass,
2568 fundecl, function,
2569 parmnum + 1);
2570
2571 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2572 && INTEGRAL_TYPE_P (type)
2573 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2574 parmval = default_conversion (parmval);
2575 }
2576 result = tree_cons (NULL_TREE, parmval, result);
2577 }
2578 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2579 && (TYPE_PRECISION (TREE_TYPE (val))
2580 < TYPE_PRECISION (double_type_node))
2581 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (val))))
2582 /* Convert `float' to `double'. */
2583 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2584 else if ((invalid_func_diag =
2585 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
2586 {
2587 error (invalid_func_diag, "");
2588 return error_mark_node;
2589 }
2590 else
2591 /* Convert `short' and `char' to full-size `int'. */
2592 result = tree_cons (NULL_TREE, default_conversion (val), result);
2593
2594 if (typetail)
2595 typetail = TREE_CHAIN (typetail);
2596 }
2597
2598 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2599 {
2600 error ("too few arguments to function %qE", function);
2601 return error_mark_node;
2602 }
2603
2604 return nreverse (result);
2605}
2606
2607/* This is the entry point used by the parser to build unary operators
2608 in the input. CODE, a tree_code, specifies the unary operator, and
2609 ARG is the operand. For unary plus, the C parser currently uses
2610 CONVERT_EXPR for code. */
2611
2612struct c_expr
2613parser_build_unary_op (enum tree_code code, struct c_expr arg)
2614{
2615 struct c_expr result;
2616
2617 result.original_code = ERROR_MARK;
2618 result.value = build_unary_op (code, arg.value, 0);
2619
2620 if (TREE_OVERFLOW_P (result.value) && !TREE_OVERFLOW_P (arg.value))
2621 overflow_warning (result.value);
2622
2623 return result;
2624}
2625
2626/* This is the entry point used by the parser to build binary operators
2627 in the input. CODE, a tree_code, specifies the binary operator, and
2628 ARG1 and ARG2 are the operands. In addition to constructing the
2629 expression, we check for operands that were written with other binary
2630 operators in a way that is likely to confuse the user. */
2631
2632struct c_expr
2633parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2634 struct c_expr arg2)
2635{
2636 struct c_expr result;
2637
2638 enum tree_code code1 = arg1.original_code;
2639 enum tree_code code2 = arg2.original_code;
2640
2641 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2642 result.original_code = code;
2643
2644 if (TREE_CODE (result.value) == ERROR_MARK)
2645 return result;
2646
2647 /* Check for cases such as x+y<<z which users are likely
2648 to misinterpret. */
2649 if (warn_parentheses)
2650 warn_about_parentheses (code, code1, code2);
2651
2652 /* Warn about comparisons against string literals, with the exception
2653 of testing for equality or inequality of a string literal with NULL. */
2654 if (code == EQ_EXPR || code == NE_EXPR)
2655 {
2656 if ((code1 == STRING_CST && !integer_zerop (arg2.value))
2657 || (code2 == STRING_CST && !integer_zerop (arg1.value)))
2658 warning (OPT_Waddress,
2659 "comparison with string literal results in unspecified behaviour");
2660 }
2661 else if (TREE_CODE_CLASS (code) == tcc_comparison
2662 && (code1 == STRING_CST || code2 == STRING_CST))
2663 warning (OPT_Waddress,
2664 "comparison with string literal results in unspecified behaviour");
2665
2666 if (TREE_OVERFLOW_P (result.value)
2667 && !TREE_OVERFLOW_P (arg1.value)
2668 && !TREE_OVERFLOW_P (arg2.value))
2669 overflow_warning (result.value);
2670
2671 return result;
2672}
2673
2674/* Return a tree for the difference of pointers OP0 and OP1.
2675 The resulting tree has type int. */
2676
2677static tree
2678pointer_diff (tree op0, tree op1)
2679{
2680 tree restype = ptrdiff_type_node;
2681
2682 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2683 tree con0, con1, lit0, lit1;
2684 tree orig_op1 = op1;
2685
2686 if (pedantic || warn_pointer_arith)
2687 {
2688 if (TREE_CODE (target_type) == VOID_TYPE)
2689 pedwarn ("pointer of type %<void *%> used in subtraction");
2690 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2691 pedwarn ("pointer to a function used in subtraction");
2692 }
2693
2694 /* If the conversion to ptrdiff_type does anything like widening or
2695 converting a partial to an integral mode, we get a convert_expression
2696 that is in the way to do any simplifications.
2697 (fold-const.c doesn't know that the extra bits won't be needed.
2698 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2699 different mode in place.)
2700 So first try to find a common term here 'by hand'; we want to cover
2701 at least the cases that occur in legal static initializers. */
2702 if ((TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == CONVERT_EXPR)
2703 && (TYPE_PRECISION (TREE_TYPE (op0))
2704 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
2705 con0 = TREE_OPERAND (op0, 0);
2706 else
2707 con0 = op0;
2708 if ((TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == CONVERT_EXPR)
2709 && (TYPE_PRECISION (TREE_TYPE (op1))
2710 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))))
2711 con1 = TREE_OPERAND (op1, 0);
2712 else
2713 con1 = op1;
2714
2715 if (TREE_CODE (con0) == PLUS_EXPR)
2716 {
2717 lit0 = TREE_OPERAND (con0, 1);
2718 con0 = TREE_OPERAND (con0, 0);
2719 }
2720 else
2721 lit0 = integer_zero_node;
2722
2723 if (TREE_CODE (con1) == PLUS_EXPR)
2724 {
2725 lit1 = TREE_OPERAND (con1, 1);
2726 con1 = TREE_OPERAND (con1, 0);
2727 }
2728 else
2729 lit1 = integer_zero_node;
2730
2731 if (operand_equal_p (con0, con1, 0))
2732 {
2733 op0 = lit0;
2734 op1 = lit1;
2735 }
2736
2737
2738 /* First do the subtraction as integers;
2739 then drop through to build the divide operator.
2740 Do not do default conversions on the minus operator
2741 in case restype is a short type. */
2742
2743 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2744 convert (restype, op1), 0);
2745 /* This generates an error if op1 is pointer to incomplete type. */
2746 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2747 error ("arithmetic on pointer to an incomplete type");
2748
2749 /* This generates an error if op0 is pointer to incomplete type. */
2750 op1 = c_size_in_bytes (target_type);
2751
2752 /* Divide by the size, in easiest possible way. */
2753 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2754}
2755
2756/* Construct and perhaps optimize a tree representation
2757 for a unary operation. CODE, a tree_code, specifies the operation
2758 and XARG is the operand.
2759 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2760 the default promotions (such as from short to int).
2761 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2762 allows non-lvalues; this is only used to handle conversion of non-lvalue
2763 arrays to pointers in C99. */
2764
2765tree
2766build_unary_op (enum tree_code code, tree xarg, int flag)
2767{
2768 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2769 tree arg = xarg;
2770 tree argtype = 0;
2771 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2772 tree val;
2773 int noconvert = flag;
2774 const char *invalid_op_diag;
2775
2776 if (typecode == ERROR_MARK)
2777 return error_mark_node;
2778 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2779 typecode = INTEGER_TYPE;
2780
2781 if ((invalid_op_diag
2782 = targetm.invalid_unary_op (code, TREE_TYPE (xarg))))
2783 {
2784 error (invalid_op_diag, "");
2785 return error_mark_node;
2786 }
2787
2788 switch (code)
2789 {
2790 case CONVERT_EXPR:
2791 /* This is used for unary plus, because a CONVERT_EXPR
2792 is enough to prevent anybody from looking inside for
2793 associativity, but won't generate any code. */
2794 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2795 || typecode == COMPLEX_TYPE
2796 || typecode == VECTOR_TYPE))
2797 {
2798 error ("wrong type argument to unary plus");
2799 return error_mark_node;
2800 }
2801 else if (!noconvert)
2802 arg = default_conversion (arg);
2803 arg = non_lvalue (arg);
2804 break;
2805
2806 case NEGATE_EXPR:
2807 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2808 || typecode == COMPLEX_TYPE
2809 || typecode == VECTOR_TYPE))
2810 {
2811 error ("wrong type argument to unary minus");
2812 return error_mark_node;
2813 }
2814 else if (!noconvert)
2815 arg = default_conversion (arg);
2816 break;
2817
2818 case BIT_NOT_EXPR:
2819 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2820 {
2821 if (!noconvert)
2822 arg = default_conversion (arg);
2823 }
2824 else if (typecode == COMPLEX_TYPE)
2825 {
2826 code = CONJ_EXPR;
2827 if (pedantic)
2828 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2829 if (!noconvert)
2830 arg = default_conversion (arg);
2831 }
2832 else
2833 {
2834 error ("wrong type argument to bit-complement");
2835 return error_mark_node;
2836 }
2837 break;
2838
2839 case ABS_EXPR:
2840 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2841 {
2842 error ("wrong type argument to abs");
2843 return error_mark_node;
2844 }
2845 else if (!noconvert)
2846 arg = default_conversion (arg);
2847 break;
2848
2849 case CONJ_EXPR:
2850 /* Conjugating a real value is a no-op, but allow it anyway. */
2851 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2852 || typecode == COMPLEX_TYPE))
2853 {
2854 error ("wrong type argument to conjugation");
2855 return error_mark_node;
2856 }
2857 else if (!noconvert)
2858 arg = default_conversion (arg);
2859 break;
2860
2861 case TRUTH_NOT_EXPR:
2862 if (typecode != INTEGER_TYPE
2863 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2864 && typecode != COMPLEX_TYPE)
2865 {
2866 error ("wrong type argument to unary exclamation mark");
2867 return error_mark_node;
2868 }
2869 arg = c_objc_common_truthvalue_conversion (arg);
2870 return invert_truthvalue (arg);
2871
2872 case REALPART_EXPR:
2873 if (TREE_CODE (arg) == COMPLEX_CST)
2874 return TREE_REALPART (arg);
2875 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2876 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2877 else
2878 return arg;
2879
2880 case IMAGPART_EXPR:
2881 if (TREE_CODE (arg) == COMPLEX_CST)
2882 return TREE_IMAGPART (arg);
2883 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2884 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2885 else
2886 return convert (TREE_TYPE (arg), integer_zero_node);
2887
2888 case PREINCREMENT_EXPR:
2889 case POSTINCREMENT_EXPR:
2890 case PREDECREMENT_EXPR:
2891 case POSTDECREMENT_EXPR:
2892
2893 /* Increment or decrement the real part of the value,
2894 and don't change the imaginary part. */
2895 if (typecode == COMPLEX_TYPE)
2896 {
2897 tree real, imag;
2898
2899 if (pedantic)
2900 pedwarn ("ISO C does not support %<++%> and %<--%>"
2901 " on complex types");
2902
2903 arg = stabilize_reference (arg);
2904 real = build_unary_op (REALPART_EXPR, arg, 1);
2905 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2906 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2907 build_unary_op (code, real, 1), imag);
2908 }
2909
2910 /* Report invalid types. */
2911
2912 if (typecode != POINTER_TYPE
2913 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2914 {
2915 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2916 error ("wrong type argument to increment");
2917 else
2918 error ("wrong type argument to decrement");
2919
2920 return error_mark_node;
2921 }
2922
2923 {
2924 tree inc;
2925 tree result_type = TREE_TYPE (arg);
2926
2927 arg = get_unwidened (arg, 0);
2928 argtype = TREE_TYPE (arg);
2929
2930 /* Compute the increment. */
2931
2932 if (typecode == POINTER_TYPE)
2933 {
2934 /* If pointer target is an undefined struct,
2935 we just cannot know how to do the arithmetic. */
2936 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2937 {
2938 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2939 error ("increment of pointer to unknown structure");
2940 else
2941 error ("decrement of pointer to unknown structure");
2942 }
2943 else if ((pedantic || warn_pointer_arith)
2944 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2945 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2946 {
2947 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2948 pedwarn ("wrong type argument to increment");
2949 else
2950 pedwarn ("wrong type argument to decrement");
2951 }
2952
2953 inc = c_size_in_bytes (TREE_TYPE (result_type));
2954 }
2955 else
2956 inc = integer_one_node;
2957
2958 inc = convert (argtype, inc);
2959
2960 /* Complain about anything else that is not a true lvalue. */
2961 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2962 || code == POSTINCREMENT_EXPR)
2963 ? lv_increment
2964 : lv_decrement)))
2965 return error_mark_node;
2966
2967 /* Report a read-only lvalue. */
2968 if (TREE_READONLY (arg))
2969 {
2970 readonly_error (arg,
2971 ((code == PREINCREMENT_EXPR
2972 || code == POSTINCREMENT_EXPR)
2973 ? lv_increment : lv_decrement));
2974 return error_mark_node;
2975 }
2976
2977 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2978 val = boolean_increment (code, arg);
2979 else
2980 val = build2 (code, TREE_TYPE (arg), arg, inc);
2981 TREE_SIDE_EFFECTS (val) = 1;
2982 val = convert (result_type, val);
2983 if (TREE_CODE (val) != code)
2984 TREE_NO_WARNING (val) = 1;
2985 return val;
2986 }
2987
2988 case ADDR_EXPR:
2989 /* Note that this operation never does default_conversion. */
2990
2991 /* Let &* cancel out to simplify resulting code. */
2992 if (TREE_CODE (arg) == INDIRECT_REF)
2993 {
2994 /* Don't let this be an lvalue. */
2995 if (lvalue_p (TREE_OPERAND (arg, 0)))
2996 return non_lvalue (TREE_OPERAND (arg, 0));
2997 return TREE_OPERAND (arg, 0);
2998 }
2999
3000 /* For &x[y], return x+y */
3001 if (TREE_CODE (arg) == ARRAY_REF)
3002 {
3003 tree op0 = TREE_OPERAND (arg, 0);
3004 if (!c_mark_addressable (op0))
3005 return error_mark_node;
3006 return build_binary_op (PLUS_EXPR,
3007 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE
3008 ? array_to_pointer_conversion (op0)
3009 : op0),
3010 TREE_OPERAND (arg, 1), 1);
3011 }
3012
3013 /* Anything not already handled and not a true memory reference
3014 or a non-lvalue array is an error. */
3015 else if (typecode != FUNCTION_TYPE && !flag
3016 && !lvalue_or_else (arg, lv_addressof))
3017 return error_mark_node;
3018
3019 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3020 argtype = TREE_TYPE (arg);
3021
3022 /* If the lvalue is const or volatile, merge that into the type
3023 to which the address will point. Note that you can't get a
3024 restricted pointer by taking the address of something, so we
3025 only have to deal with `const' and `volatile' here. */
3026 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
3027 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3028 argtype = c_build_type_variant (argtype,
3029 TREE_READONLY (arg),
3030 TREE_THIS_VOLATILE (arg));
3031
3032 if (!c_mark_addressable (arg))
3033 return error_mark_node;
3034
3035 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
3036 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
3037
3038 argtype = build_pointer_type (argtype);
3039
3040 /* ??? Cope with user tricks that amount to offsetof. Delete this
3041 when we have proper support for integer constant expressions. */
3042 val = get_base_address (arg);
3043 if (val && TREE_CODE (val) == INDIRECT_REF
3044 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
3045 {
3046 tree op0 = fold_convert (argtype, fold_offsetof (arg, val)), op1;
3047
3048 op1 = fold_convert (argtype, TREE_OPERAND (val, 0));
3049 return fold_build2 (PLUS_EXPR, argtype, op0, op1);
3050 }
3051
3052 val = build1 (ADDR_EXPR, argtype, arg);
3053
3054 return val;
3055
3056 default:
3057 gcc_unreachable ();
3058 }
3059
3060 if (argtype == 0)
3061 argtype = TREE_TYPE (arg);
3062 return require_constant_value ? fold_build1_initializer (code, argtype, arg)
3063 : fold_build1 (code, argtype, arg);
3064}
3065
3066/* Return nonzero if REF is an lvalue valid for this language.
3067 Lvalues can be assigned, unless their type has TYPE_READONLY.
3068 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
3069
3070static int
3071lvalue_p (tree ref)
3072{
3073 enum tree_code code = TREE_CODE (ref);
3074
3075 switch (code)
3076 {
3077 case REALPART_EXPR:
3078 case IMAGPART_EXPR:
3079 case COMPONENT_REF:
3080 return lvalue_p (TREE_OPERAND (ref, 0));
3081
3082 case COMPOUND_LITERAL_EXPR:
3083 case STRING_CST:
3084 return 1;
3085
3086 case INDIRECT_REF:
3087 case ARRAY_REF:
3088 case VAR_DECL:
3089 case PARM_DECL:
3090 case RESULT_DECL:
3091 case ERROR_MARK:
3092 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3093 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3094
3095 case BIND_EXPR:
3096 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3097
3098 default:
3099 return 0;
3100 }
3101}
3102
3103/* Give an error for storing in something that is 'const'. */
3104
3105static void
3106readonly_error (tree arg, enum lvalue_use use)
3107{
3108 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement
3109 || use == lv_asm);
3110 /* Using this macro rather than (for example) arrays of messages
3111 ensures that all the format strings are checked at compile
3112 time. */
3113#define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \
3114 : (use == lv_increment ? (I) \
3115 : (use == lv_decrement ? (D) : (AS))))
3116 if (TREE_CODE (arg) == COMPONENT_REF)
3117 {
3118 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3119 readonly_error (TREE_OPERAND (arg, 0), use);
3120 else
3121 error (READONLY_MSG (G_("assignment of read-only member %qD"),
3122 G_("increment of read-only member %qD"),
3123 G_("decrement of read-only member %qD"),
3124 G_("read-only member %qD used as %<asm%> output")),
3125 TREE_OPERAND (arg, 1));
3126 }
3127 else if (TREE_CODE (arg) == VAR_DECL)
3128 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
3129 G_("increment of read-only variable %qD"),
3130 G_("decrement of read-only variable %qD"),
3131 G_("read-only variable %qD used as %<asm%> output")),
3132 arg);
3133 else
3134 error (READONLY_MSG (G_("assignment of read-only location"),
3135 G_("increment of read-only location"),
3136 G_("decrement of read-only location"),
3137 G_("read-only location used as %<asm%> output")));
3138}
3139
3140
3141/* Return nonzero if REF is an lvalue valid for this language;
3142 otherwise, print an error message and return zero. USE says
3143 how the lvalue is being used and so selects the error message. */
3144
3145static int
3146lvalue_or_else (tree ref, enum lvalue_use use)
3147{
3148 int win = lvalue_p (ref);
3149
3150 if (!win)
3151 lvalue_error (use);
3152
3153 return win;
3154}
3155
3156/* Mark EXP saying that we need to be able to take the
3157 address of it; it should not be allocated in a register.
3158 Returns true if successful. */
3159
3160bool
3161c_mark_addressable (tree exp)
3162{
3163 tree x = exp;
3164
3165 while (1)
3166 switch (TREE_CODE (x))
3167 {
3168 case COMPONENT_REF:
3169 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3170 {
3171 error
3172 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
3173 return false;
3174 }
3175
3176 /* ... fall through ... */
3177
3178 case ADDR_EXPR:
3179 case ARRAY_REF:
3180 case REALPART_EXPR:
3181 case IMAGPART_EXPR:
3182 x = TREE_OPERAND (x, 0);
3183 break;
3184
3185 case COMPOUND_LITERAL_EXPR:
3186 case CONSTRUCTOR:
3187 TREE_ADDRESSABLE (x) = 1;
3188 return true;
3189
3190 case VAR_DECL:
3191 case CONST_DECL:
3192 case PARM_DECL:
3193 case RESULT_DECL:
3194 if (C_DECL_REGISTER (x)
3195 && DECL_NONLOCAL (x))
3196 {
3197 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3198 {
3199 error
3200 ("global register variable %qD used in nested function", x);
3201 return false;
3202 }
3203 pedwarn ("register variable %qD used in nested function", x);
3204 }
3205 else if (C_DECL_REGISTER (x))
3206 {
3207 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3208 error ("address of global register variable %qD requested", x);
3209 else
3210 error ("address of register variable %qD requested", x);
3211 return false;
3212 }
3213
3214 /* drops in */
3215 case FUNCTION_DECL:
3216 TREE_ADDRESSABLE (x) = 1;
3217 /* drops out */
3218 default:
3219 return true;
3220 }
3221}
3222
3223/* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3224
3225tree
3226build_conditional_expr (tree ifexp, tree op1, tree op2)
3227{
3228 tree type1;
3229 tree type2;
3230 enum tree_code code1;
3231 enum tree_code code2;
3232 tree result_type = NULL;
3233 tree orig_op1 = op1, orig_op2 = op2;
3234
3235 /* Promote both alternatives. */
3236
3237 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3238 op1 = default_conversion (op1);
3239 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3240 op2 = default_conversion (op2);
3241
3242 if (TREE_CODE (ifexp) == ERROR_MARK
3243 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3244 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3245 return error_mark_node;
3246
3247 type1 = TREE_TYPE (op1);
3248 code1 = TREE_CODE (type1);
3249 type2 = TREE_TYPE (op2);
3250 code2 = TREE_CODE (type2);
3251
3252 /* C90 does not permit non-lvalue arrays in conditional expressions.
3253 In C99 they will be pointers by now. */
3254 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
3255 {
3256 error ("non-lvalue array in conditional expression");
3257 return error_mark_node;
3258 }
3259
3260 /* Quickly detect the usual case where op1 and op2 have the same type
3261 after promotion. */
3262 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3263 {
3264 if (type1 == type2)
3265 result_type = type1;
3266 else
3267 result_type = TYPE_MAIN_VARIANT (type1);
3268 }
3269 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3270 || code1 == COMPLEX_TYPE)
3271 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3272 || code2 == COMPLEX_TYPE))
3273 {
3274 result_type = c_common_type (type1, type2);
3275
3276 /* If -Wsign-compare, warn here if type1 and type2 have
3277 different signedness. We'll promote the signed to unsigned
3278 and later code won't know it used to be different.
3279 Do this check on the original types, so that explicit casts
3280 will be considered, but default promotions won't. */
3281 if (warn_sign_compare && !skip_evaluation)
3282 {
3283 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3284 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3285
3286 if (unsigned_op1 ^ unsigned_op2)
3287 {
3288 bool ovf;
3289
3290 /* Do not warn if the result type is signed, since the
3291 signed type will only be chosen if it can represent
3292 all the values of the unsigned type. */
3293 if (!TYPE_UNSIGNED (result_type))
3294 /* OK */;
3295 /* Do not warn if the signed quantity is an unsuffixed
3296 integer literal (or some static constant expression
3297 involving such literals) and it is non-negative. */
3298 else if ((unsigned_op2
3299 && tree_expr_nonnegative_warnv_p (op1, &ovf))
3300 || (unsigned_op1
3301 && tree_expr_nonnegative_warnv_p (op2, &ovf)))
3302 /* OK */;
3303 else
3304 warning (0, "signed and unsigned type in conditional expression");
3305 }
3306 }
3307 }
3308 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3309 {
3310 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3311 pedwarn ("ISO C forbids conditional expr with only one void side");
3312 result_type = void_type_node;
3313 }
3314 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3315 {
3316 if (comp_target_types (type1, type2))
3317 result_type = common_pointer_type (type1, type2);
3318 else if (null_pointer_constant_p (orig_op1))
3319 result_type = qualify_type (type2, type1);
3320 else if (null_pointer_constant_p (orig_op2))
3321 result_type = qualify_type (type1, type2);
3322 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3323 {
3324 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3325 pedwarn ("ISO C forbids conditional expr between "
3326 "%<void *%> and function pointer");
3327 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
3328 TREE_TYPE (type2)));
3329 }
3330 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3331 {
3332 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3333 pedwarn ("ISO C forbids conditional expr between "
3334 "%<void *%> and function pointer");
3335 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3336 TREE_TYPE (type1)));
3337 }
3338 else
3339 {
3340 pedwarn ("pointer type mismatch in conditional expression");
3341 result_type = build_pointer_type (void_type_node);
3342 }
3343 }
3344 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3345 {
3346 if (!null_pointer_constant_p (orig_op2))
3347 pedwarn ("pointer/integer type mismatch in conditional expression");
3348 else
3349 {
3350 op2 = null_pointer_node;
3351 }
3352 result_type = type1;
3353 }
3354 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3355 {
3356 if (!null_pointer_constant_p (orig_op1))
3357 pedwarn ("pointer/integer type mismatch in conditional expression");
3358 else
3359 {
3360 op1 = null_pointer_node;
3361 }
3362 result_type = type2;
3363 }
3364
3365 if (!result_type)
3366 {
3367 if (flag_cond_mismatch)
3368 result_type = void_type_node;
3369 else
3370 {
3371 error ("type mismatch in conditional expression");
3372 return error_mark_node;
3373 }
3374 }
3375
3376 /* Merge const and volatile flags of the incoming types. */
3377 result_type
3378 = build_type_variant (result_type,
3379 TREE_READONLY (op1) || TREE_READONLY (op2),
3380 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3381
3382 if (result_type != TREE_TYPE (op1))
3383 op1 = convert_and_check (result_type, op1);
3384 if (result_type != TREE_TYPE (op2))
3385 op2 = convert_and_check (result_type, op2);
3386
3387 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3388}
3389
3390/* Return a compound expression that performs two expressions and
3391 returns the value of the second of them. */
3392
3393tree
3394build_compound_expr (tree expr1, tree expr2)
3395{
3396 if (!TREE_SIDE_EFFECTS (expr1))
3397 {
3398 /* The left-hand operand of a comma expression is like an expression
3399 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3400 any side-effects, unless it was explicitly cast to (void). */
3401 if (warn_unused_value)
3402 {
3403 if (VOID_TYPE_P (TREE_TYPE (expr1))
3404 && (TREE_CODE (expr1) == NOP_EXPR
3405 || TREE_CODE (expr1) == CONVERT_EXPR))
3406 ; /* (void) a, b */
3407 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3408 && TREE_CODE (expr1) == COMPOUND_EXPR
3409 && (TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR
3410 || TREE_CODE (TREE_OPERAND (expr1, 1)) == NOP_EXPR))
3411 ; /* (void) a, (void) b, c */
3412 else
3413 warning (0, "left-hand operand of comma expression has no effect");
3414 }
3415 }
3416
3417 /* With -Wunused, we should also warn if the left-hand operand does have
3418 side-effects, but computes a value which is not used. For example, in
3419 `foo() + bar(), baz()' the result of the `+' operator is not used,
3420 so we should issue a warning. */
3421 else if (warn_unused_value)
3422 warn_if_unused_value (expr1, input_location);
3423
3424 if (expr2 == error_mark_node)
3425 return error_mark_node;
3426
3427 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3428}
3429
3430/* Build an expression representing a cast to type TYPE of expression EXPR. */
3431
3432tree
3433build_c_cast (tree type, tree expr)
3434{
3435 tree value = expr;
3436
3437 if (type == error_mark_node || expr == error_mark_node)
3438 return error_mark_node;
3439
3440 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3441 only in <protocol> qualifications. But when constructing cast expressions,
3442 the protocols do matter and must be kept around. */
3443 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3444 return build1 (NOP_EXPR, type, expr);
3445
3446 type = TYPE_MAIN_VARIANT (type);
3447
3448 if (TREE_CODE (type) == ARRAY_TYPE)
3449 {
3450 error ("cast specifies array type");
3451 return error_mark_node;
3452 }
3453
3454 if (TREE_CODE (type) == FUNCTION_TYPE)
3455 {
3456 error ("cast specifies function type");
3457 return error_mark_node;
3458 }
3459
3460 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3461 {
3462 if (pedantic)
3463 {
3464 if (TREE_CODE (type) == RECORD_TYPE
3465 || TREE_CODE (type) == UNION_TYPE)
3466 pedwarn ("ISO C forbids casting nonscalar to the same type");
3467 }
3468 }
3469 else if (TREE_CODE (type) == UNION_TYPE)
3470 {
3471 tree field;
3472
3473 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3474 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3475 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3476 break;
3477
3478 if (field)
3479 {
3480 tree t;
3481
3482 if (pedantic)
3483 pedwarn ("ISO C forbids casts to union type");
3484 t = digest_init (type,
3485 build_constructor_single (type, field, value),
3486 true, 0);
3487 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3488 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3489 return t;
3490 }
3491 error ("cast to union type from type not present in union");
3492 return error_mark_node;
3493 }
3494 else
3495 {
3496 tree otype, ovalue;
3497
3498 if (type == void_type_node)
3499 return build1 (CONVERT_EXPR, type, value);
3500
3501 otype = TREE_TYPE (value);
3502
3503 /* Optionally warn about potentially worrisome casts. */
3504
3505 if (warn_cast_qual
3506 && TREE_CODE (type) == POINTER_TYPE
3507 && TREE_CODE (otype) == POINTER_TYPE)
3508 {
3509 tree in_type = type;
3510 tree in_otype = otype;
3511 int added = 0;
3512 int discarded = 0;
3513
3514 /* Check that the qualifiers on IN_TYPE are a superset of
3515 the qualifiers of IN_OTYPE. The outermost level of
3516 POINTER_TYPE nodes is uninteresting and we stop as soon
3517 as we hit a non-POINTER_TYPE node on either type. */
3518 do
3519 {
3520 in_otype = TREE_TYPE (in_otype);
3521 in_type = TREE_TYPE (in_type);
3522
3523 /* GNU C allows cv-qualified function types. 'const'
3524 means the function is very pure, 'volatile' means it
3525 can't return. We need to warn when such qualifiers
3526 are added, not when they're taken away. */
3527 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3528 && TREE_CODE (in_type) == FUNCTION_TYPE)
3529 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3530 else
3531 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3532 }
3533 while (TREE_CODE (in_type) == POINTER_TYPE
3534 && TREE_CODE (in_otype) == POINTER_TYPE);
3535
3536 if (added)
3537 warning (0, "cast adds new qualifiers to function type");
3538
3539 if (discarded)
3540 /* There are qualifiers present in IN_OTYPE that are not
3541 present in IN_TYPE. */
3542 warning (0, "cast discards qualifiers from pointer target type");
3543 }
3544
3545 /* Warn about possible alignment problems. */
3546 if (STRICT_ALIGNMENT
3547 && TREE_CODE (type) == POINTER_TYPE
3548 && TREE_CODE (otype) == POINTER_TYPE
3549 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3550 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3551 /* Don't warn about opaque types, where the actual alignment
3552 restriction is unknown. */
3553 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3554 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3555 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3556 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3557 warning (OPT_Wcast_align,
3558 "cast increases required alignment of target type");
3559
3560 if (TREE_CODE (type) == INTEGER_TYPE
3561 && TREE_CODE (otype) == POINTER_TYPE
3562 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
3563 /* Unlike conversion of integers to pointers, where the
3564 warning is disabled for converting constants because
3565 of cases such as SIG_*, warn about converting constant
3566 pointers to integers. In some cases it may cause unwanted
3567 sign extension, and a warning is appropriate. */
3568 warning (OPT_Wpointer_to_int_cast,
3569 "cast from pointer to integer of different size");
3570
3571 if (TREE_CODE (value) == CALL_EXPR
3572 && TREE_CODE (type) != TREE_CODE (otype))
3573 warning (OPT_Wbad_function_cast, "cast from function call of type %qT "
3574 "to non-matching type %qT", otype, type);
3575
3576 if (TREE_CODE (type) == POINTER_TYPE
3577 && TREE_CODE (otype) == INTEGER_TYPE
3578 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3579 /* Don't warn about converting any constant. */
3580 && !TREE_CONSTANT (value))
3581 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer "
3582 "of different size");
3583
3584 if (warn_strict_aliasing <= 2)
3585 strict_aliasing_warning (otype, type, expr);
3586
3587 /* If pedantic, warn for conversions between function and object
3588 pointer types, except for converting a null pointer constant
3589 to function pointer type. */
3590 if (pedantic
3591 && TREE_CODE (type) == POINTER_TYPE
3592 && TREE_CODE (otype) == POINTER_TYPE
3593 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3594 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3595 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3596
3597 if (pedantic
3598 && TREE_CODE (type) == POINTER_TYPE
3599 && TREE_CODE (otype) == POINTER_TYPE
3600 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3601 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3602 && !null_pointer_constant_p (value))
3603 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3604
3605 ovalue = value;
3606 value = convert (type, value);
3607
3608 /* Ignore any integer overflow caused by the cast. */
3609 if (TREE_CODE (value) == INTEGER_CST)
3610 {
3611 if (CONSTANT_CLASS_P (ovalue)
3612 && (TREE_OVERFLOW (ovalue) || TREE_CONSTANT_OVERFLOW (ovalue)))
3613 {
3614 /* Avoid clobbering a shared constant. */
3615 value = copy_node (value);
3616 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3617 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3618 }
3619 else if (TREE_OVERFLOW (value) || TREE_CONSTANT_OVERFLOW (value))
3620 /* Reset VALUE's overflow flags, ensuring constant sharing. */
3621 value = build_int_cst_wide (TREE_TYPE (value),
3622 TREE_INT_CST_LOW (value),
3623 TREE_INT_CST_HIGH (value));
3624 }
3625 }
3626
3627 /* Don't let a cast be an lvalue. */
3628 if (value == expr)
3629 value = non_lvalue (value);
3630
3631 return value;
3632}
3633
3634/* Interpret a cast of expression EXPR to type TYPE. */
3635tree
3636c_cast_expr (struct c_type_name *type_name, tree expr)
3637{
3638 tree type;
3639 int saved_wsp = warn_strict_prototypes;
3640
3641 /* This avoids warnings about unprototyped casts on
3642 integers. E.g. "#define SIG_DFL (void(*)())0". */
3643 if (TREE_CODE (expr) == INTEGER_CST)
3644 warn_strict_prototypes = 0;
3645 type = groktypename (type_name);
3646 warn_strict_prototypes = saved_wsp;
3647
3648 return build_c_cast (type, expr);
3649}
3650
3651/* Build an assignment expression of lvalue LHS from value RHS.
3652 MODIFYCODE is the code for a binary operator that we use
3653 to combine the old value of LHS with RHS to get the new value.
3654 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3655
3656tree
3657build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3658{
3659 tree result;
3660 tree newrhs;
3661 tree lhstype = TREE_TYPE (lhs);
3662 tree olhstype = lhstype;
3663
3664 /* Types that aren't fully specified cannot be used in assignments. */
3665 lhs = require_complete_type (lhs);
3666
3667 /* Avoid duplicate error messages from operands that had errors. */
3668 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3669 return error_mark_node;
3670
3671 if (!lvalue_or_else (lhs, lv_assign))
3672 return error_mark_node;
3673
3674 STRIP_TYPE_NOPS (rhs);
3675
3676 newrhs = rhs;
3677
3678 /* If a binary op has been requested, combine the old LHS value with the RHS
3679 producing the value we should actually store into the LHS. */
3680
3681 if (modifycode != NOP_EXPR)
3682 {
3683 lhs = stabilize_reference (lhs);
3684 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3685 }
3686
3687 /* Give an error for storing in something that is 'const'. */
3688
3689 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3690 || ((TREE_CODE (lhstype) == RECORD_TYPE
3691 || TREE_CODE (lhstype) == UNION_TYPE)
3692 && C_TYPE_FIELDS_READONLY (lhstype)))
3693 {
3694 readonly_error (lhs, lv_assign);
3695 return error_mark_node;
3696 }
3697
3698 /* If storing into a structure or union member,
3699 it has probably been given type `int'.
3700 Compute the type that would go with
3701 the actual amount of storage the member occupies. */
3702
3703 if (TREE_CODE (lhs) == COMPONENT_REF
3704 && (TREE_CODE (lhstype) == INTEGER_TYPE
3705 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3706 || TREE_CODE (lhstype) == REAL_TYPE
3707 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3708 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3709
3710 /* If storing in a field that is in actuality a short or narrower than one,
3711 we must store in the field in its actual type. */
3712
3713 if (lhstype != TREE_TYPE (lhs))
3714 {
3715 lhs = copy_node (lhs);
3716 TREE_TYPE (lhs) = lhstype;
3717 }
3718
3719 /* Convert new value to destination type. */
3720
3721 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3722 NULL_TREE, NULL_TREE, 0);
3723 if (TREE_CODE (newrhs) == ERROR_MARK)
3724 return error_mark_node;
3725
3726 /* Emit ObjC write barrier, if necessary. */
3727 if (c_dialect_objc () && flag_objc_gc)
3728 {
3729 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3730 if (result)
3731 return result;
3732 }
3733
3734 /* Scan operands. */
3735
3736 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3737 TREE_SIDE_EFFECTS (result) = 1;
3738
3739 /* If we got the LHS in a different type for storing in,
3740 convert the result back to the nominal type of LHS
3741 so that the value we return always has the same type
3742 as the LHS argument. */
3743
3744 if (olhstype == TREE_TYPE (result))
3745 return result;
3746 return convert_for_assignment (olhstype, result, ic_assign,
3747 NULL_TREE, NULL_TREE, 0);
3748}
3749
3750/* Convert value RHS to type TYPE as preparation for an assignment
3751 to an lvalue of type TYPE.
3752 The real work of conversion is done by `convert'.
3753 The purpose of this function is to generate error messages
3754 for assignments that are not allowed in C.
3755 ERRTYPE says whether it is argument passing, assignment,
3756 initialization or return.
3757
3758 FUNCTION is a tree for the function being called.
3759 PARMNUM is the number of the argument, for printing in error messages. */
3760
3761static tree
3762convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3763 tree fundecl, tree function, int parmnum)
3764{
3765 enum tree_code codel = TREE_CODE (type);
3766 tree rhstype;
3767 enum tree_code coder;
3768 tree rname = NULL_TREE;
3769 bool objc_ok = false;
3770
3771 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3772 {
3773 tree selector;
3774 /* Change pointer to function to the function itself for
3775 diagnostics. */
3776 if (TREE_CODE (function) == ADDR_EXPR
3777 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3778 function = TREE_OPERAND (function, 0);
3779
3780 /* Handle an ObjC selector specially for diagnostics. */
3781 selector = objc_message_selector ();
3782 rname = function;
3783 if (selector && parmnum > 2)
3784 {
3785 rname = selector;
3786 parmnum -= 2;
3787 }
3788 }
3789
3790 /* This macro is used to emit diagnostics to ensure that all format
3791 strings are complete sentences, visible to gettext and checked at
3792 compile time. */
3793#define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3794 do { \
3795 switch (errtype) \
3796 { \
3797 case ic_argpass: \
3798 pedwarn (AR, parmnum, rname); \
3799 break; \
3800 case ic_argpass_nonproto: \
3801 warning (0, AR, parmnum, rname); \
3802 break; \
3803 case ic_assign: \
3804 pedwarn (AS); \
3805 break; \
3806 case ic_init: \
3807 pedwarn (IN); \
3808 break; \
3809 case ic_return: \
3810 pedwarn (RE); \
3811 break; \
3812 default: \
3813 gcc_unreachable (); \
3814 } \
3815 } while (0)
3816
3817 STRIP_TYPE_NOPS (rhs);
3818
3819 if (optimize && TREE_CODE (rhs) == VAR_DECL
3820 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE)
3821 rhs = decl_constant_value_for_broken_optimization (rhs);
3822
3823 rhstype = TREE_TYPE (rhs);
3824 coder = TREE_CODE (rhstype);
3825
3826 if (coder == ERROR_MARK)
3827 return error_mark_node;
3828
3829 if (c_dialect_objc ())
3830 {
3831 int parmno;
3832
3833 switch (errtype)
3834 {
3835 case ic_return:
3836 parmno = 0;
3837 break;
3838
3839 case ic_assign:
3840 parmno = -1;
3841 break;
3842
3843 case ic_init:
3844 parmno = -2;
3845 break;
3846
3847 default:
3848 parmno = parmnum;
3849 break;
3850 }
3851
3852 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
3853 }
3854
3855 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3856 return rhs;
3857
3858 if (coder == VOID_TYPE)
3859 {
3860 /* Except for passing an argument to an unprototyped function,
3861 this is a constraint violation. When passing an argument to
3862 an unprototyped function, it is compile-time undefined;
3863 making it a constraint in that case was rejected in
3864 DR#252. */
3865 error ("void value not ignored as it ought to be");
3866 return error_mark_node;
3867 }
3868 /* A type converts to a reference to it.
3869 This code doesn't fully support references, it's just for the
3870 special case of va_start and va_copy. */
3871 if (codel == REFERENCE_TYPE
3872 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3873 {
3874 if (!lvalue_p (rhs))
3875 {
3876 error ("cannot pass rvalue to reference parameter");
3877 return error_mark_node;
3878 }
3879 if (!c_mark_addressable (rhs))
3880 return error_mark_node;
3881 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3882
3883 /* We already know that these two types are compatible, but they
3884 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3885 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3886 likely to be va_list, a typedef to __builtin_va_list, which
3887 is different enough that it will cause problems later. */
3888 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3889 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3890
3891 rhs = build1 (NOP_EXPR, type, rhs);
3892 return rhs;
3893 }
3894 /* Some types can interconvert without explicit casts. */
3895 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
| 1/* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
4 Free Software Foundation, Inc.
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 2, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
17
18You should have received a copy of the GNU General Public License
19along with GCC; see the file COPYING. If not, write to the Free
20Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
2102110-1301, USA. */
22
23
24/* This file is part of the C front end.
25 It contains routines to build C expressions given their operands,
26 including computing the types of the result, C-specific error checks,
27 and some optimization. */
28
29#include "config.h"
30#include "system.h"
31#include "coretypes.h"
32#include "tm.h"
33#include "rtl.h"
34#include "tree.h"
35#include "langhooks.h"
36#include "c-tree.h"
37#include "tm_p.h"
38#include "flags.h"
39#include "output.h"
40#include "expr.h"
41#include "toplev.h"
42#include "intl.h"
43#include "ggc.h"
44#include "target.h"
45#include "tree-iterator.h"
46#include "tree-gimple.h"
47#include "tree-flow.h"
48
49/* Possible cases of implicit bad conversions. Used to select
50 diagnostic messages in convert_for_assignment. */
51enum impl_conv {
52 ic_argpass,
53 ic_argpass_nonproto,
54 ic_assign,
55 ic_init,
56 ic_return
57};
58
59/* The level of nesting inside "__alignof__". */
60int in_alignof;
61
62/* The level of nesting inside "sizeof". */
63int in_sizeof;
64
65/* The level of nesting inside "typeof". */
66int in_typeof;
67
68struct c_label_context_se *label_context_stack_se;
69struct c_label_context_vm *label_context_stack_vm;
70
71/* Nonzero if we've already printed a "missing braces around initializer"
72 message within this initializer. */
73static int missing_braces_mentioned;
74
75static int require_constant_value;
76static int require_constant_elements;
77
78static bool null_pointer_constant_p (tree);
79static tree qualify_type (tree, tree);
80static int tagged_types_tu_compatible_p (tree, tree);
81static int comp_target_types (tree, tree);
82static int function_types_compatible_p (tree, tree);
83static int type_lists_compatible_p (tree, tree);
84static tree decl_constant_value_for_broken_optimization (tree);
85static tree lookup_field (tree, tree);
86static tree convert_arguments (tree, tree, tree, tree);
87static tree pointer_diff (tree, tree);
88static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree,
89 int);
90static tree valid_compound_expr_initializer (tree, tree);
91static void push_string (const char *);
92static void push_member_name (tree);
93static int spelling_length (void);
94static char *print_spelling (char *);
95static void warning_init (const char *);
96static tree digest_init (tree, tree, bool, int);
97static void output_init_element (tree, bool, tree, tree, int);
98static void output_pending_init_elements (int);
99static int set_designator (int);
100static void push_range_stack (tree);
101static void add_pending_init (tree, tree);
102static void set_nonincremental_init (void);
103static void set_nonincremental_init_from_string (tree);
104static tree find_init_member (tree);
105static void readonly_error (tree, enum lvalue_use);
106static int lvalue_or_else (tree, enum lvalue_use);
107static int lvalue_p (tree);
108static void record_maybe_used_decl (tree);
109static int comptypes_internal (tree, tree);
110
111/* Return true if EXP is a null pointer constant, false otherwise. */
112
113static bool
114null_pointer_constant_p (tree expr)
115{
116 /* This should really operate on c_expr structures, but they aren't
117 yet available everywhere required. */
118 tree type = TREE_TYPE (expr);
119 return (TREE_CODE (expr) == INTEGER_CST
120 && !TREE_CONSTANT_OVERFLOW (expr)
121 && integer_zerop (expr)
122 && (INTEGRAL_TYPE_P (type)
123 || (TREE_CODE (type) == POINTER_TYPE
124 && VOID_TYPE_P (TREE_TYPE (type))
125 && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED)));
126}
127 /* This is a cache to hold if two types are compatible or not. */
128
129struct tagged_tu_seen_cache {
130 const struct tagged_tu_seen_cache * next;
131 tree t1;
132 tree t2;
133 /* The return value of tagged_types_tu_compatible_p if we had seen
134 these two types already. */
135 int val;
136};
137
138static const struct tagged_tu_seen_cache * tagged_tu_seen_base;
139static void free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *);
140
141/* Do `exp = require_complete_type (exp);' to make sure exp
142 does not have an incomplete type. (That includes void types.) */
143
144tree
145require_complete_type (tree value)
146{
147 tree type = TREE_TYPE (value);
148
149 if (value == error_mark_node || type == error_mark_node)
150 return error_mark_node;
151
152 /* First, detect a valid value with a complete type. */
153 if (COMPLETE_TYPE_P (type))
154 return value;
155
156 c_incomplete_type_error (value, type);
157 return error_mark_node;
158}
159
160/* Print an error message for invalid use of an incomplete type.
161 VALUE is the expression that was used (or 0 if that isn't known)
162 and TYPE is the type that was invalid. */
163
164void
165c_incomplete_type_error (tree value, tree type)
166{
167 const char *type_code_string;
168
169 /* Avoid duplicate error message. */
170 if (TREE_CODE (type) == ERROR_MARK)
171 return;
172
173 if (value != 0 && (TREE_CODE (value) == VAR_DECL
174 || TREE_CODE (value) == PARM_DECL))
175 error ("%qD has an incomplete type", value);
176 else
177 {
178 retry:
179 /* We must print an error message. Be clever about what it says. */
180
181 switch (TREE_CODE (type))
182 {
183 case RECORD_TYPE:
184 type_code_string = "struct";
185 break;
186
187 case UNION_TYPE:
188 type_code_string = "union";
189 break;
190
191 case ENUMERAL_TYPE:
192 type_code_string = "enum";
193 break;
194
195 case VOID_TYPE:
196 error ("invalid use of void expression");
197 return;
198
199 case ARRAY_TYPE:
200 if (TYPE_DOMAIN (type))
201 {
202 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
203 {
204 error ("invalid use of flexible array member");
205 return;
206 }
207 type = TREE_TYPE (type);
208 goto retry;
209 }
210 error ("invalid use of array with unspecified bounds");
211 return;
212
213 default:
214 gcc_unreachable ();
215 }
216
217 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
218 error ("invalid use of undefined type %<%s %E%>",
219 type_code_string, TYPE_NAME (type));
220 else
221 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
222 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type));
223 }
224}
225
226/* Given a type, apply default promotions wrt unnamed function
227 arguments and return the new type. */
228
229tree
230c_type_promotes_to (tree type)
231{
232 if (TYPE_MAIN_VARIANT (type) == float_type_node)
233 return double_type_node;
234
235 if (c_promoting_integer_type_p (type))
236 {
237 /* Preserve unsignedness if not really getting any wider. */
238 if (TYPE_UNSIGNED (type)
239 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
240 return unsigned_type_node;
241 return integer_type_node;
242 }
243
244 return type;
245}
246
247/* Return a variant of TYPE which has all the type qualifiers of LIKE
248 as well as those of TYPE. */
249
250static tree
251qualify_type (tree type, tree like)
252{
253 return c_build_qualified_type (type,
254 TYPE_QUALS (type) | TYPE_QUALS (like));
255}
256
257/* Return true iff the given tree T is a variable length array. */
258
259bool
260c_vla_type_p (tree t)
261{
262 if (TREE_CODE (t) == ARRAY_TYPE
263 && C_TYPE_VARIABLE_SIZE (t))
264 return true;
265 return false;
266}
267
268/* Return the composite type of two compatible types.
269
270 We assume that comptypes has already been done and returned
271 nonzero; if that isn't so, this may crash. In particular, we
272 assume that qualifiers match. */
273
274tree
275composite_type (tree t1, tree t2)
276{
277 enum tree_code code1;
278 enum tree_code code2;
279 tree attributes;
280
281 /* Save time if the two types are the same. */
282
283 if (t1 == t2) return t1;
284
285 /* If one type is nonsense, use the other. */
286 if (t1 == error_mark_node)
287 return t2;
288 if (t2 == error_mark_node)
289 return t1;
290
291 code1 = TREE_CODE (t1);
292 code2 = TREE_CODE (t2);
293
294 /* Merge the attributes. */
295 attributes = targetm.merge_type_attributes (t1, t2);
296
297 /* If one is an enumerated type and the other is the compatible
298 integer type, the composite type might be either of the two
299 (DR#013 question 3). For consistency, use the enumerated type as
300 the composite type. */
301
302 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
303 return t1;
304 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
305 return t2;
306
307 gcc_assert (code1 == code2);
308
309 switch (code1)
310 {
311 case POINTER_TYPE:
312 /* For two pointers, do this recursively on the target type. */
313 {
314 tree pointed_to_1 = TREE_TYPE (t1);
315 tree pointed_to_2 = TREE_TYPE (t2);
316 tree target = composite_type (pointed_to_1, pointed_to_2);
317 t1 = build_pointer_type (target);
318 t1 = build_type_attribute_variant (t1, attributes);
319 return qualify_type (t1, t2);
320 }
321
322 case ARRAY_TYPE:
323 {
324 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
325 int quals;
326 tree unqual_elt;
327 tree d1 = TYPE_DOMAIN (t1);
328 tree d2 = TYPE_DOMAIN (t2);
329 bool d1_variable, d2_variable;
330 bool d1_zero, d2_zero;
331
332 /* We should not have any type quals on arrays at all. */
333 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2));
334
335 d1_zero = d1 == 0 || !TYPE_MAX_VALUE (d1);
336 d2_zero = d2 == 0 || !TYPE_MAX_VALUE (d2);
337
338 d1_variable = (!d1_zero
339 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
340 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
341 d2_variable = (!d2_zero
342 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
343 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
344 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
345 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
346
347 /* Save space: see if the result is identical to one of the args. */
348 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)
349 && (d2_variable || d2_zero || !d1_variable))
350 return build_type_attribute_variant (t1, attributes);
351 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)
352 && (d1_variable || d1_zero || !d2_variable))
353 return build_type_attribute_variant (t2, attributes);
354
355 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
356 return build_type_attribute_variant (t1, attributes);
357 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
358 return build_type_attribute_variant (t2, attributes);
359
360 /* Merge the element types, and have a size if either arg has
361 one. We may have qualifiers on the element types. To set
362 up TYPE_MAIN_VARIANT correctly, we need to form the
363 composite of the unqualified types and add the qualifiers
364 back at the end. */
365 quals = TYPE_QUALS (strip_array_types (elt));
366 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
367 t1 = build_array_type (unqual_elt,
368 TYPE_DOMAIN ((TYPE_DOMAIN (t1)
369 && (d2_variable
370 || d2_zero
371 || !d1_variable))
372 ? t1
373 : t2));
374 t1 = c_build_qualified_type (t1, quals);
375 return build_type_attribute_variant (t1, attributes);
376 }
377
378 case ENUMERAL_TYPE:
379 case RECORD_TYPE:
380 case UNION_TYPE:
381 if (attributes != NULL)
382 {
383 /* Try harder not to create a new aggregate type. */
384 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
385 return t1;
386 if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
387 return t2;
388 }
389 return build_type_attribute_variant (t1, attributes);
390
391 case FUNCTION_TYPE:
392 /* Function types: prefer the one that specified arg types.
393 If both do, merge the arg types. Also merge the return types. */
394 {
395 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
396 tree p1 = TYPE_ARG_TYPES (t1);
397 tree p2 = TYPE_ARG_TYPES (t2);
398 int len;
399 tree newargs, n;
400 int i;
401
402 /* Save space: see if the result is identical to one of the args. */
403 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
404 return build_type_attribute_variant (t1, attributes);
405 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
406 return build_type_attribute_variant (t2, attributes);
407
408 /* Simple way if one arg fails to specify argument types. */
409 if (TYPE_ARG_TYPES (t1) == 0)
410 {
411 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
412 t1 = build_type_attribute_variant (t1, attributes);
413 return qualify_type (t1, t2);
414 }
415 if (TYPE_ARG_TYPES (t2) == 0)
416 {
417 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
418 t1 = build_type_attribute_variant (t1, attributes);
419 return qualify_type (t1, t2);
420 }
421
422 /* If both args specify argument types, we must merge the two
423 lists, argument by argument. */
424 /* Tell global_bindings_p to return false so that variable_size
425 doesn't die on VLAs in parameter types. */
426 c_override_global_bindings_to_false = true;
427
428 len = list_length (p1);
429 newargs = 0;
430
431 for (i = 0; i < len; i++)
432 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
433
434 n = newargs;
435
436 for (; p1;
437 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
438 {
439 /* A null type means arg type is not specified.
440 Take whatever the other function type has. */
441 if (TREE_VALUE (p1) == 0)
442 {
443 TREE_VALUE (n) = TREE_VALUE (p2);
444 goto parm_done;
445 }
446 if (TREE_VALUE (p2) == 0)
447 {
448 TREE_VALUE (n) = TREE_VALUE (p1);
449 goto parm_done;
450 }
451
452 /* Given wait (union {union wait *u; int *i} *)
453 and wait (union wait *),
454 prefer union wait * as type of parm. */
455 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
456 && TREE_VALUE (p1) != TREE_VALUE (p2))
457 {
458 tree memb;
459 tree mv2 = TREE_VALUE (p2);
460 if (mv2 && mv2 != error_mark_node
461 && TREE_CODE (mv2) != ARRAY_TYPE)
462 mv2 = TYPE_MAIN_VARIANT (mv2);
463 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
464 memb; memb = TREE_CHAIN (memb))
465 {
466 tree mv3 = TREE_TYPE (memb);
467 if (mv3 && mv3 != error_mark_node
468 && TREE_CODE (mv3) != ARRAY_TYPE)
469 mv3 = TYPE_MAIN_VARIANT (mv3);
470 if (comptypes (mv3, mv2))
471 {
472 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
473 TREE_VALUE (p2));
474 if (pedantic)
475 pedwarn ("function types not truly compatible in ISO C");
476 goto parm_done;
477 }
478 }
479 }
480 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
481 && TREE_VALUE (p2) != TREE_VALUE (p1))
482 {
483 tree memb;
484 tree mv1 = TREE_VALUE (p1);
485 if (mv1 && mv1 != error_mark_node
486 && TREE_CODE (mv1) != ARRAY_TYPE)
487 mv1 = TYPE_MAIN_VARIANT (mv1);
488 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
489 memb; memb = TREE_CHAIN (memb))
490 {
491 tree mv3 = TREE_TYPE (memb);
492 if (mv3 && mv3 != error_mark_node
493 && TREE_CODE (mv3) != ARRAY_TYPE)
494 mv3 = TYPE_MAIN_VARIANT (mv3);
495 if (comptypes (mv3, mv1))
496 {
497 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
498 TREE_VALUE (p1));
499 if (pedantic)
500 pedwarn ("function types not truly compatible in ISO C");
501 goto parm_done;
502 }
503 }
504 }
505 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
506 parm_done: ;
507 }
508
509 c_override_global_bindings_to_false = false;
510 t1 = build_function_type (valtype, newargs);
511 t1 = qualify_type (t1, t2);
512 /* ... falls through ... */
513 }
514
515 default:
516 return build_type_attribute_variant (t1, attributes);
517 }
518
519}
520
521/* Return the type of a conditional expression between pointers to
522 possibly differently qualified versions of compatible types.
523
524 We assume that comp_target_types has already been done and returned
525 nonzero; if that isn't so, this may crash. */
526
527static tree
528common_pointer_type (tree t1, tree t2)
529{
530 tree attributes;
531 tree pointed_to_1, mv1;
532 tree pointed_to_2, mv2;
533 tree target;
534
535 /* Save time if the two types are the same. */
536
537 if (t1 == t2) return t1;
538
539 /* If one type is nonsense, use the other. */
540 if (t1 == error_mark_node)
541 return t2;
542 if (t2 == error_mark_node)
543 return t1;
544
545 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
546 && TREE_CODE (t2) == POINTER_TYPE);
547
548 /* Merge the attributes. */
549 attributes = targetm.merge_type_attributes (t1, t2);
550
551 /* Find the composite type of the target types, and combine the
552 qualifiers of the two types' targets. Do not lose qualifiers on
553 array element types by taking the TYPE_MAIN_VARIANT. */
554 mv1 = pointed_to_1 = TREE_TYPE (t1);
555 mv2 = pointed_to_2 = TREE_TYPE (t2);
556 if (TREE_CODE (mv1) != ARRAY_TYPE)
557 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
558 if (TREE_CODE (mv2) != ARRAY_TYPE)
559 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
560 target = composite_type (mv1, mv2);
561 t1 = build_pointer_type (c_build_qualified_type
562 (target,
563 TYPE_QUALS (pointed_to_1) |
564 TYPE_QUALS (pointed_to_2)));
565 return build_type_attribute_variant (t1, attributes);
566}
567
568/* Return the common type for two arithmetic types under the usual
569 arithmetic conversions. The default conversions have already been
570 applied, and enumerated types converted to their compatible integer
571 types. The resulting type is unqualified and has no attributes.
572
573 This is the type for the result of most arithmetic operations
574 if the operands have the given two types. */
575
576static tree
577c_common_type (tree t1, tree t2)
578{
579 enum tree_code code1;
580 enum tree_code code2;
581
582 /* If one type is nonsense, use the other. */
583 if (t1 == error_mark_node)
584 return t2;
585 if (t2 == error_mark_node)
586 return t1;
587
588 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
589 t1 = TYPE_MAIN_VARIANT (t1);
590
591 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
592 t2 = TYPE_MAIN_VARIANT (t2);
593
594 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
595 t1 = build_type_attribute_variant (t1, NULL_TREE);
596
597 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
598 t2 = build_type_attribute_variant (t2, NULL_TREE);
599
600 /* Save time if the two types are the same. */
601
602 if (t1 == t2) return t1;
603
604 code1 = TREE_CODE (t1);
605 code2 = TREE_CODE (t2);
606
607 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
608 || code1 == REAL_TYPE || code1 == INTEGER_TYPE);
609 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
610 || code2 == REAL_TYPE || code2 == INTEGER_TYPE);
611
612 /* When one operand is a decimal float type, the other operand cannot be
613 a generic float type or a complex type. We also disallow vector types
614 here. */
615 if ((DECIMAL_FLOAT_TYPE_P (t1) || DECIMAL_FLOAT_TYPE_P (t2))
616 && !(DECIMAL_FLOAT_TYPE_P (t1) && DECIMAL_FLOAT_TYPE_P (t2)))
617 {
618 if (code1 == VECTOR_TYPE || code2 == VECTOR_TYPE)
619 {
620 error ("can%'t mix operands of decimal float and vector types");
621 return error_mark_node;
622 }
623 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
624 {
625 error ("can%'t mix operands of decimal float and complex types");
626 return error_mark_node;
627 }
628 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
629 {
630 error ("can%'t mix operands of decimal float and other float types");
631 return error_mark_node;
632 }
633 }
634
635 /* If one type is a vector type, return that type. (How the usual
636 arithmetic conversions apply to the vector types extension is not
637 precisely specified.) */
638 if (code1 == VECTOR_TYPE)
639 return t1;
640
641 if (code2 == VECTOR_TYPE)
642 return t2;
643
644 /* If one type is complex, form the common type of the non-complex
645 components, then make that complex. Use T1 or T2 if it is the
646 required type. */
647 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
648 {
649 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
650 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
651 tree subtype = c_common_type (subtype1, subtype2);
652
653 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
654 return t1;
655 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
656 return t2;
657 else
658 return build_complex_type (subtype);
659 }
660
661 /* If only one is real, use it as the result. */
662
663 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
664 return t1;
665
666 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
667 return t2;
668
669 /* If both are real and either are decimal floating point types, use
670 the decimal floating point type with the greater precision. */
671
672 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
673 {
674 if (TYPE_MAIN_VARIANT (t1) == dfloat128_type_node
675 || TYPE_MAIN_VARIANT (t2) == dfloat128_type_node)
676 return dfloat128_type_node;
677 else if (TYPE_MAIN_VARIANT (t1) == dfloat64_type_node
678 || TYPE_MAIN_VARIANT (t2) == dfloat64_type_node)
679 return dfloat64_type_node;
680 else if (TYPE_MAIN_VARIANT (t1) == dfloat32_type_node
681 || TYPE_MAIN_VARIANT (t2) == dfloat32_type_node)
682 return dfloat32_type_node;
683 }
684
685 /* Both real or both integers; use the one with greater precision. */
686
687 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
688 return t1;
689 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
690 return t2;
691
692 /* Same precision. Prefer long longs to longs to ints when the
693 same precision, following the C99 rules on integer type rank
694 (which are equivalent to the C90 rules for C90 types). */
695
696 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
697 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
698 return long_long_unsigned_type_node;
699
700 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
701 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
702 {
703 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
704 return long_long_unsigned_type_node;
705 else
706 return long_long_integer_type_node;
707 }
708
709 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
710 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
711 return long_unsigned_type_node;
712
713 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
714 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
715 {
716 /* But preserve unsignedness from the other type,
717 since long cannot hold all the values of an unsigned int. */
718 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
719 return long_unsigned_type_node;
720 else
721 return long_integer_type_node;
722 }
723
724 /* Likewise, prefer long double to double even if same size. */
725 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
726 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
727 return long_double_type_node;
728
729 /* Otherwise prefer the unsigned one. */
730
731 if (TYPE_UNSIGNED (t1))
732 return t1;
733 else
734 return t2;
735}
736
737/* Wrapper around c_common_type that is used by c-common.c and other
738 front end optimizations that remove promotions. ENUMERAL_TYPEs
739 are allowed here and are converted to their compatible integer types.
740 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
741 preferably a non-Boolean type as the common type. */
742tree
743common_type (tree t1, tree t2)
744{
745 if (TREE_CODE (t1) == ENUMERAL_TYPE)
746 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
747 if (TREE_CODE (t2) == ENUMERAL_TYPE)
748 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
749
750 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
751 if (TREE_CODE (t1) == BOOLEAN_TYPE
752 && TREE_CODE (t2) == BOOLEAN_TYPE)
753 return boolean_type_node;
754
755 /* If either type is BOOLEAN_TYPE, then return the other. */
756 if (TREE_CODE (t1) == BOOLEAN_TYPE)
757 return t2;
758 if (TREE_CODE (t2) == BOOLEAN_TYPE)
759 return t1;
760
761 return c_common_type (t1, t2);
762}
763
764/* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
765 or various other operations. Return 2 if they are compatible
766 but a warning may be needed if you use them together. */
767
768int
769comptypes (tree type1, tree type2)
770{
771 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base;
772 int val;
773
774 val = comptypes_internal (type1, type2);
775 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1);
776
777 return val;
778}
779
780/* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
781 or various other operations. Return 2 if they are compatible
782 but a warning may be needed if you use them together. This
783 differs from comptypes, in that we don't free the seen types. */
784
785static int
786comptypes_internal (tree type1, tree type2)
787{
788 tree t1 = type1;
789 tree t2 = type2;
790 int attrval, val;
791
792 /* Suppress errors caused by previously reported errors. */
793
794 if (t1 == t2 || !t1 || !t2
795 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
796 return 1;
797
798 /* If either type is the internal version of sizetype, return the
799 language version. */
800 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
801 && TYPE_ORIG_SIZE_TYPE (t1))
802 t1 = TYPE_ORIG_SIZE_TYPE (t1);
803
804 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
805 && TYPE_ORIG_SIZE_TYPE (t2))
806 t2 = TYPE_ORIG_SIZE_TYPE (t2);
807
808
809 /* Enumerated types are compatible with integer types, but this is
810 not transitive: two enumerated types in the same translation unit
811 are compatible with each other only if they are the same type. */
812
813 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
814 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
815 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
816 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
817
818 if (t1 == t2)
819 return 1;
820
821 /* Different classes of types can't be compatible. */
822
823 if (TREE_CODE (t1) != TREE_CODE (t2))
824 return 0;
825
826 /* Qualifiers must match. C99 6.7.3p9 */
827
828 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
829 return 0;
830
831 /* Allow for two different type nodes which have essentially the same
832 definition. Note that we already checked for equality of the type
833 qualifiers (just above). */
834
835 if (TREE_CODE (t1) != ARRAY_TYPE
836 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
837 return 1;
838
839 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
840 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
841 return 0;
842
843 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
844 val = 0;
845
846 switch (TREE_CODE (t1))
847 {
848 case POINTER_TYPE:
849 /* Do not remove mode or aliasing information. */
850 if (TYPE_MODE (t1) != TYPE_MODE (t2)
851 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
852 break;
853 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
854 ? 1 : comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2)));
855 break;
856
857 case FUNCTION_TYPE:
858 val = function_types_compatible_p (t1, t2);
859 break;
860
861 case ARRAY_TYPE:
862 {
863 tree d1 = TYPE_DOMAIN (t1);
864 tree d2 = TYPE_DOMAIN (t2);
865 bool d1_variable, d2_variable;
866 bool d1_zero, d2_zero;
867 val = 1;
868
869 /* Target types must match incl. qualifiers. */
870 if (TREE_TYPE (t1) != TREE_TYPE (t2)
871 && 0 == (val = comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2))))
872 return 0;
873
874 /* Sizes must match unless one is missing or variable. */
875 if (d1 == 0 || d2 == 0 || d1 == d2)
876 break;
877
878 d1_zero = !TYPE_MAX_VALUE (d1);
879 d2_zero = !TYPE_MAX_VALUE (d2);
880
881 d1_variable = (!d1_zero
882 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
883 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
884 d2_variable = (!d2_zero
885 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
886 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
887 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
888 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
889
890 if (d1_variable || d2_variable)
891 break;
892 if (d1_zero && d2_zero)
893 break;
894 if (d1_zero || d2_zero
895 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
896 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
897 val = 0;
898
899 break;
900 }
901
902 case ENUMERAL_TYPE:
903 case RECORD_TYPE:
904 case UNION_TYPE:
905 if (val != 1 && !same_translation_unit_p (t1, t2))
906 {
907 tree a1 = TYPE_ATTRIBUTES (t1);
908 tree a2 = TYPE_ATTRIBUTES (t2);
909
910 if (! attribute_list_contained (a1, a2)
911 && ! attribute_list_contained (a2, a1))
912 break;
913
914 if (attrval != 2)
915 return tagged_types_tu_compatible_p (t1, t2);
916 val = tagged_types_tu_compatible_p (t1, t2);
917 }
918 break;
919
920 case VECTOR_TYPE:
921 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
922 && comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2));
923 break;
924
925 default:
926 break;
927 }
928 return attrval == 2 && val == 1 ? 2 : val;
929}
930
931/* Return 1 if TTL and TTR are pointers to types that are equivalent,
932 ignoring their qualifiers. */
933
934static int
935comp_target_types (tree ttl, tree ttr)
936{
937 int val;
938 tree mvl, mvr;
939
940 /* Do not lose qualifiers on element types of array types that are
941 pointer targets by taking their TYPE_MAIN_VARIANT. */
942 mvl = TREE_TYPE (ttl);
943 mvr = TREE_TYPE (ttr);
944 if (TREE_CODE (mvl) != ARRAY_TYPE)
945 mvl = TYPE_MAIN_VARIANT (mvl);
946 if (TREE_CODE (mvr) != ARRAY_TYPE)
947 mvr = TYPE_MAIN_VARIANT (mvr);
948 val = comptypes (mvl, mvr);
949
950 if (val == 2 && pedantic)
951 pedwarn ("types are not quite compatible");
952 return val;
953}
954
955/* Subroutines of `comptypes'. */
956
957/* Determine whether two trees derive from the same translation unit.
958 If the CONTEXT chain ends in a null, that tree's context is still
959 being parsed, so if two trees have context chains ending in null,
960 they're in the same translation unit. */
961int
962same_translation_unit_p (tree t1, tree t2)
963{
964 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
965 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
966 {
967 case tcc_declaration:
968 t1 = DECL_CONTEXT (t1); break;
969 case tcc_type:
970 t1 = TYPE_CONTEXT (t1); break;
971 case tcc_exceptional:
972 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
973 default: gcc_unreachable ();
974 }
975
976 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
977 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
978 {
979 case tcc_declaration:
980 t2 = DECL_CONTEXT (t2); break;
981 case tcc_type:
982 t2 = TYPE_CONTEXT (t2); break;
983 case tcc_exceptional:
984 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
985 default: gcc_unreachable ();
986 }
987
988 return t1 == t2;
989}
990
991/* Allocate the seen two types, assuming that they are compatible. */
992
993static struct tagged_tu_seen_cache *
994alloc_tagged_tu_seen_cache (tree t1, tree t2)
995{
996 struct tagged_tu_seen_cache *tu = XNEW (struct tagged_tu_seen_cache);
997 tu->next = tagged_tu_seen_base;
998 tu->t1 = t1;
999 tu->t2 = t2;
1000
1001 tagged_tu_seen_base = tu;
1002
1003 /* The C standard says that two structures in different translation
1004 units are compatible with each other only if the types of their
1005 fields are compatible (among other things). We assume that they
1006 are compatible until proven otherwise when building the cache.
1007 An example where this can occur is:
1008 struct a
1009 {
1010 struct a *next;
1011 };
1012 If we are comparing this against a similar struct in another TU,
1013 and did not assume they were compatible, we end up with an infinite
1014 loop. */
1015 tu->val = 1;
1016 return tu;
1017}
1018
1019/* Free the seen types until we get to TU_TIL. */
1020
1021static void
1022free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *tu_til)
1023{
1024 const struct tagged_tu_seen_cache *tu = tagged_tu_seen_base;
1025 while (tu != tu_til)
1026 {
1027 struct tagged_tu_seen_cache *tu1 = (struct tagged_tu_seen_cache*)tu;
1028 tu = tu1->next;
1029 free (tu1);
1030 }
1031 tagged_tu_seen_base = tu_til;
1032}
1033
1034/* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
1035 compatible. If the two types are not the same (which has been
1036 checked earlier), this can only happen when multiple translation
1037 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
1038 rules. */
1039
1040static int
1041tagged_types_tu_compatible_p (tree t1, tree t2)
1042{
1043 tree s1, s2;
1044 bool needs_warning = false;
1045
1046 /* We have to verify that the tags of the types are the same. This
1047 is harder than it looks because this may be a typedef, so we have
1048 to go look at the original type. It may even be a typedef of a
1049 typedef...
1050 In the case of compiler-created builtin structs the TYPE_DECL
1051 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
1052 while (TYPE_NAME (t1)
1053 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
1054 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
1055 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
1056
1057 while (TYPE_NAME (t2)
1058 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
1059 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
1060 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
1061
1062 /* C90 didn't have the requirement that the two tags be the same. */
1063 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
1064 return 0;
1065
1066 /* C90 didn't say what happened if one or both of the types were
1067 incomplete; we choose to follow C99 rules here, which is that they
1068 are compatible. */
1069 if (TYPE_SIZE (t1) == NULL
1070 || TYPE_SIZE (t2) == NULL)
1071 return 1;
1072
1073 {
1074 const struct tagged_tu_seen_cache * tts_i;
1075 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
1076 if (tts_i->t1 == t1 && tts_i->t2 == t2)
1077 return tts_i->val;
1078 }
1079
1080 switch (TREE_CODE (t1))
1081 {
1082 case ENUMERAL_TYPE:
1083 {
1084 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1085 /* Speed up the case where the type values are in the same order. */
1086 tree tv1 = TYPE_VALUES (t1);
1087 tree tv2 = TYPE_VALUES (t2);
1088
1089 if (tv1 == tv2)
1090 {
1091 return 1;
1092 }
1093
1094 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
1095 {
1096 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
1097 break;
1098 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
1099 {
1100 tu->val = 0;
1101 return 0;
1102 }
1103 }
1104
1105 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
1106 {
1107 return 1;
1108 }
1109 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
1110 {
1111 tu->val = 0;
1112 return 0;
1113 }
1114
1115 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
1116 {
1117 tu->val = 0;
1118 return 0;
1119 }
1120
1121 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
1122 {
1123 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
1124 if (s2 == NULL
1125 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
1126 {
1127 tu->val = 0;
1128 return 0;
1129 }
1130 }
1131 return 1;
1132 }
1133
1134 case UNION_TYPE:
1135 {
1136 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1137 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
1138 {
1139 tu->val = 0;
1140 return 0;
1141 }
1142
1143 /* Speed up the common case where the fields are in the same order. */
1144 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2;
1145 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1146 {
1147 int result;
1148
1149
1150 if (DECL_NAME (s1) == NULL
1151 || DECL_NAME (s1) != DECL_NAME (s2))
1152 break;
1153 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1154 if (result == 0)
1155 {
1156 tu->val = 0;
1157 return 0;
1158 }
1159 if (result == 2)
1160 needs_warning = true;
1161
1162 if (TREE_CODE (s1) == FIELD_DECL
1163 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1164 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1165 {
1166 tu->val = 0;
1167 return 0;
1168 }
1169 }
1170 if (!s1 && !s2)
1171 {
1172 tu->val = needs_warning ? 2 : 1;
1173 return tu->val;
1174 }
1175
1176 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
1177 {
1178 bool ok = false;
1179
1180 if (DECL_NAME (s1) != NULL)
1181 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
1182 if (DECL_NAME (s1) == DECL_NAME (s2))
1183 {
1184 int result;
1185 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1186 if (result == 0)
1187 {
1188 tu->val = 0;
1189 return 0;
1190 }
1191 if (result == 2)
1192 needs_warning = true;
1193
1194 if (TREE_CODE (s1) == FIELD_DECL
1195 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1196 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1197 break;
1198
1199 ok = true;
1200 break;
1201 }
1202 if (!ok)
1203 {
1204 tu->val = 0;
1205 return 0;
1206 }
1207 }
1208 tu->val = needs_warning ? 2 : 10;
1209 return tu->val;
1210 }
1211
1212 case RECORD_TYPE:
1213 {
1214 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1215
1216 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
1217 s1 && s2;
1218 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1219 {
1220 int result;
1221 if (TREE_CODE (s1) != TREE_CODE (s2)
1222 || DECL_NAME (s1) != DECL_NAME (s2))
1223 break;
1224 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1225 if (result == 0)
1226 break;
1227 if (result == 2)
1228 needs_warning = true;
1229
1230 if (TREE_CODE (s1) == FIELD_DECL
1231 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1232 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1233 break;
1234 }
1235 if (s1 && s2)
1236 tu->val = 0;
1237 else
1238 tu->val = needs_warning ? 2 : 1;
1239 return tu->val;
1240 }
1241
1242 default:
1243 gcc_unreachable ();
1244 }
1245}
1246
1247/* Return 1 if two function types F1 and F2 are compatible.
1248 If either type specifies no argument types,
1249 the other must specify a fixed number of self-promoting arg types.
1250 Otherwise, if one type specifies only the number of arguments,
1251 the other must specify that number of self-promoting arg types.
1252 Otherwise, the argument types must match. */
1253
1254static int
1255function_types_compatible_p (tree f1, tree f2)
1256{
1257 tree args1, args2;
1258 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1259 int val = 1;
1260 int val1;
1261 tree ret1, ret2;
1262
1263 ret1 = TREE_TYPE (f1);
1264 ret2 = TREE_TYPE (f2);
1265
1266 /* 'volatile' qualifiers on a function's return type used to mean
1267 the function is noreturn. */
1268 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1269 pedwarn ("function return types not compatible due to %<volatile%>");
1270 if (TYPE_VOLATILE (ret1))
1271 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1272 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1273 if (TYPE_VOLATILE (ret2))
1274 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1275 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1276 val = comptypes_internal (ret1, ret2);
1277 if (val == 0)
1278 return 0;
1279
1280 args1 = TYPE_ARG_TYPES (f1);
1281 args2 = TYPE_ARG_TYPES (f2);
1282
1283 /* An unspecified parmlist matches any specified parmlist
1284 whose argument types don't need default promotions. */
1285
1286 if (args1 == 0)
1287 {
1288 if (!self_promoting_args_p (args2))
1289 return 0;
1290 /* If one of these types comes from a non-prototype fn definition,
1291 compare that with the other type's arglist.
1292 If they don't match, ask for a warning (but no error). */
1293 if (TYPE_ACTUAL_ARG_TYPES (f1)
1294 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
1295 val = 2;
1296 return val;
1297 }
1298 if (args2 == 0)
1299 {
1300 if (!self_promoting_args_p (args1))
1301 return 0;
1302 if (TYPE_ACTUAL_ARG_TYPES (f2)
1303 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
1304 val = 2;
1305 return val;
1306 }
1307
1308 /* Both types have argument lists: compare them and propagate results. */
1309 val1 = type_lists_compatible_p (args1, args2);
1310 return val1 != 1 ? val1 : val;
1311}
1312
1313/* Check two lists of types for compatibility,
1314 returning 0 for incompatible, 1 for compatible,
1315 or 2 for compatible with warning. */
1316
1317static int
1318type_lists_compatible_p (tree args1, tree args2)
1319{
1320 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1321 int val = 1;
1322 int newval = 0;
1323
1324 while (1)
1325 {
1326 tree a1, mv1, a2, mv2;
1327 if (args1 == 0 && args2 == 0)
1328 return val;
1329 /* If one list is shorter than the other,
1330 they fail to match. */
1331 if (args1 == 0 || args2 == 0)
1332 return 0;
1333 mv1 = a1 = TREE_VALUE (args1);
1334 mv2 = a2 = TREE_VALUE (args2);
1335 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1336 mv1 = TYPE_MAIN_VARIANT (mv1);
1337 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1338 mv2 = TYPE_MAIN_VARIANT (mv2);
1339 /* A null pointer instead of a type
1340 means there is supposed to be an argument
1341 but nothing is specified about what type it has.
1342 So match anything that self-promotes. */
1343 if (a1 == 0)
1344 {
1345 if (c_type_promotes_to (a2) != a2)
1346 return 0;
1347 }
1348 else if (a2 == 0)
1349 {
1350 if (c_type_promotes_to (a1) != a1)
1351 return 0;
1352 }
1353 /* If one of the lists has an error marker, ignore this arg. */
1354 else if (TREE_CODE (a1) == ERROR_MARK
1355 || TREE_CODE (a2) == ERROR_MARK)
1356 ;
1357 else if (!(newval = comptypes_internal (mv1, mv2)))
1358 {
1359 /* Allow wait (union {union wait *u; int *i} *)
1360 and wait (union wait *) to be compatible. */
1361 if (TREE_CODE (a1) == UNION_TYPE
1362 && (TYPE_NAME (a1) == 0
1363 || TYPE_TRANSPARENT_UNION (a1))
1364 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1365 && tree_int_cst_equal (TYPE_SIZE (a1),
1366 TYPE_SIZE (a2)))
1367 {
1368 tree memb;
1369 for (memb = TYPE_FIELDS (a1);
1370 memb; memb = TREE_CHAIN (memb))
1371 {
1372 tree mv3 = TREE_TYPE (memb);
1373 if (mv3 && mv3 != error_mark_node
1374 && TREE_CODE (mv3) != ARRAY_TYPE)
1375 mv3 = TYPE_MAIN_VARIANT (mv3);
1376 if (comptypes_internal (mv3, mv2))
1377 break;
1378 }
1379 if (memb == 0)
1380 return 0;
1381 }
1382 else if (TREE_CODE (a2) == UNION_TYPE
1383 && (TYPE_NAME (a2) == 0
1384 || TYPE_TRANSPARENT_UNION (a2))
1385 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1386 && tree_int_cst_equal (TYPE_SIZE (a2),
1387 TYPE_SIZE (a1)))
1388 {
1389 tree memb;
1390 for (memb = TYPE_FIELDS (a2);
1391 memb; memb = TREE_CHAIN (memb))
1392 {
1393 tree mv3 = TREE_TYPE (memb);
1394 if (mv3 && mv3 != error_mark_node
1395 && TREE_CODE (mv3) != ARRAY_TYPE)
1396 mv3 = TYPE_MAIN_VARIANT (mv3);
1397 if (comptypes_internal (mv3, mv1))
1398 break;
1399 }
1400 if (memb == 0)
1401 return 0;
1402 }
1403 else
1404 return 0;
1405 }
1406
1407 /* comptypes said ok, but record if it said to warn. */
1408 if (newval > val)
1409 val = newval;
1410
1411 args1 = TREE_CHAIN (args1);
1412 args2 = TREE_CHAIN (args2);
1413 }
1414}
1415
1416/* Compute the size to increment a pointer by. */
1417
1418static tree
1419c_size_in_bytes (tree type)
1420{
1421 enum tree_code code = TREE_CODE (type);
1422
1423 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1424 return size_one_node;
1425
1426 if (!COMPLETE_OR_VOID_TYPE_P (type))
1427 {
1428 error ("arithmetic on pointer to an incomplete type");
1429 return size_one_node;
1430 }
1431
1432 /* Convert in case a char is more than one unit. */
1433 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1434 size_int (TYPE_PRECISION (char_type_node)
1435 / BITS_PER_UNIT));
1436}
1437
1438/* Return either DECL or its known constant value (if it has one). */
1439
1440tree
1441decl_constant_value (tree decl)
1442{
1443 if (/* Don't change a variable array bound or initial value to a constant
1444 in a place where a variable is invalid. Note that DECL_INITIAL
1445 isn't valid for a PARM_DECL. */
1446 current_function_decl != 0
1447 && TREE_CODE (decl) != PARM_DECL
1448 && !TREE_THIS_VOLATILE (decl)
1449 && TREE_READONLY (decl)
1450 && DECL_INITIAL (decl) != 0
1451 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1452 /* This is invalid if initial value is not constant.
1453 If it has either a function call, a memory reference,
1454 or a variable, then re-evaluating it could give different results. */
1455 && TREE_CONSTANT (DECL_INITIAL (decl))
1456 /* Check for cases where this is sub-optimal, even though valid. */
1457 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1458 return DECL_INITIAL (decl);
1459 return decl;
1460}
1461
1462/* Return either DECL or its known constant value (if it has one), but
1463 return DECL if pedantic or DECL has mode BLKmode. This is for
1464 bug-compatibility with the old behavior of decl_constant_value
1465 (before GCC 3.0); every use of this function is a bug and it should
1466 be removed before GCC 3.1. It is not appropriate to use pedantic
1467 in a way that affects optimization, and BLKmode is probably not the
1468 right test for avoiding misoptimizations either. */
1469
1470static tree
1471decl_constant_value_for_broken_optimization (tree decl)
1472{
1473 tree ret;
1474
1475 if (pedantic || DECL_MODE (decl) == BLKmode)
1476 return decl;
1477
1478 ret = decl_constant_value (decl);
1479 /* Avoid unwanted tree sharing between the initializer and current
1480 function's body where the tree can be modified e.g. by the
1481 gimplifier. */
1482 if (ret != decl && TREE_STATIC (decl))
1483 ret = unshare_expr (ret);
1484 return ret;
1485}
1486
1487/* Convert the array expression EXP to a pointer. */
1488static tree
1489array_to_pointer_conversion (tree exp)
1490{
1491 tree orig_exp = exp;
1492 tree type = TREE_TYPE (exp);
1493 tree adr;
1494 tree restype = TREE_TYPE (type);
1495 tree ptrtype;
1496
1497 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
1498
1499 STRIP_TYPE_NOPS (exp);
1500
1501 if (TREE_NO_WARNING (orig_exp))
1502 TREE_NO_WARNING (exp) = 1;
1503
1504 ptrtype = build_pointer_type (restype);
1505
1506 if (TREE_CODE (exp) == INDIRECT_REF)
1507 return convert (ptrtype, TREE_OPERAND (exp, 0));
1508
1509 if (TREE_CODE (exp) == VAR_DECL)
1510 {
1511 /* We are making an ADDR_EXPR of ptrtype. This is a valid
1512 ADDR_EXPR because it's the best way of representing what
1513 happens in C when we take the address of an array and place
1514 it in a pointer to the element type. */
1515 adr = build1 (ADDR_EXPR, ptrtype, exp);
1516 if (!c_mark_addressable (exp))
1517 return error_mark_node;
1518 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1519 return adr;
1520 }
1521
1522 /* This way is better for a COMPONENT_REF since it can
1523 simplify the offset for a component. */
1524 adr = build_unary_op (ADDR_EXPR, exp, 1);
1525 return convert (ptrtype, adr);
1526}
1527
1528/* Convert the function expression EXP to a pointer. */
1529static tree
1530function_to_pointer_conversion (tree exp)
1531{
1532 tree orig_exp = exp;
1533
1534 gcc_assert (TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE);
1535
1536 STRIP_TYPE_NOPS (exp);
1537
1538 if (TREE_NO_WARNING (orig_exp))
1539 TREE_NO_WARNING (exp) = 1;
1540
1541 return build_unary_op (ADDR_EXPR, exp, 0);
1542}
1543
1544/* Perform the default conversion of arrays and functions to pointers.
1545 Return the result of converting EXP. For any other expression, just
1546 return EXP after removing NOPs. */
1547
1548struct c_expr
1549default_function_array_conversion (struct c_expr exp)
1550{
1551 tree orig_exp = exp.value;
1552 tree type = TREE_TYPE (exp.value);
1553 enum tree_code code = TREE_CODE (type);
1554
1555 switch (code)
1556 {
1557 case ARRAY_TYPE:
1558 {
1559 bool not_lvalue = false;
1560 bool lvalue_array_p;
1561
1562 while ((TREE_CODE (exp.value) == NON_LVALUE_EXPR
1563 || TREE_CODE (exp.value) == NOP_EXPR
1564 || TREE_CODE (exp.value) == CONVERT_EXPR)
1565 && TREE_TYPE (TREE_OPERAND (exp.value, 0)) == type)
1566 {
1567 if (TREE_CODE (exp.value) == NON_LVALUE_EXPR)
1568 not_lvalue = true;
1569 exp.value = TREE_OPERAND (exp.value, 0);
1570 }
1571
1572 if (TREE_NO_WARNING (orig_exp))
1573 TREE_NO_WARNING (exp.value) = 1;
1574
1575 lvalue_array_p = !not_lvalue && lvalue_p (exp.value);
1576 if (!flag_isoc99 && !lvalue_array_p)
1577 {
1578 /* Before C99, non-lvalue arrays do not decay to pointers.
1579 Normally, using such an array would be invalid; but it can
1580 be used correctly inside sizeof or as a statement expression.
1581 Thus, do not give an error here; an error will result later. */
1582 return exp;
1583 }
1584
1585 exp.value = array_to_pointer_conversion (exp.value);
1586 }
1587 break;
1588 case FUNCTION_TYPE:
1589 exp.value = function_to_pointer_conversion (exp.value);
1590 break;
1591 default:
1592 STRIP_TYPE_NOPS (exp.value);
1593 if (TREE_NO_WARNING (orig_exp))
1594 TREE_NO_WARNING (exp.value) = 1;
1595 break;
1596 }
1597
1598 return exp;
1599}
1600
1601
1602/* EXP is an expression of integer type. Apply the integer promotions
1603 to it and return the promoted value. */
1604
1605tree
1606perform_integral_promotions (tree exp)
1607{
1608 tree type = TREE_TYPE (exp);
1609 enum tree_code code = TREE_CODE (type);
1610
1611 gcc_assert (INTEGRAL_TYPE_P (type));
1612
1613 /* Normally convert enums to int,
1614 but convert wide enums to something wider. */
1615 if (code == ENUMERAL_TYPE)
1616 {
1617 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1618 TYPE_PRECISION (integer_type_node)),
1619 ((TYPE_PRECISION (type)
1620 >= TYPE_PRECISION (integer_type_node))
1621 && TYPE_UNSIGNED (type)));
1622
1623 return convert (type, exp);
1624 }
1625
1626 /* ??? This should no longer be needed now bit-fields have their
1627 proper types. */
1628 if (TREE_CODE (exp) == COMPONENT_REF
1629 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1630 /* If it's thinner than an int, promote it like a
1631 c_promoting_integer_type_p, otherwise leave it alone. */
1632 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1633 TYPE_PRECISION (integer_type_node)))
1634 return convert (integer_type_node, exp);
1635
1636 if (c_promoting_integer_type_p (type))
1637 {
1638 /* Preserve unsignedness if not really getting any wider. */
1639 if (TYPE_UNSIGNED (type)
1640 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1641 return convert (unsigned_type_node, exp);
1642
1643 return convert (integer_type_node, exp);
1644 }
1645
1646 return exp;
1647}
1648
1649
1650/* Perform default promotions for C data used in expressions.
1651 Enumeral types or short or char are converted to int.
1652 In addition, manifest constants symbols are replaced by their values. */
1653
1654tree
1655default_conversion (tree exp)
1656{
1657 tree orig_exp;
1658 tree type = TREE_TYPE (exp);
1659 enum tree_code code = TREE_CODE (type);
1660
1661 /* Functions and arrays have been converted during parsing. */
1662 gcc_assert (code != FUNCTION_TYPE);
1663 if (code == ARRAY_TYPE)
1664 return exp;
1665
1666 /* Constants can be used directly unless they're not loadable. */
1667 if (TREE_CODE (exp) == CONST_DECL)
1668 exp = DECL_INITIAL (exp);
1669
1670 /* Replace a nonvolatile const static variable with its value unless
1671 it is an array, in which case we must be sure that taking the
1672 address of the array produces consistent results. */
1673 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1674 {
1675 exp = decl_constant_value_for_broken_optimization (exp);
1676 type = TREE_TYPE (exp);
1677 }
1678
1679 /* Strip no-op conversions. */
1680 orig_exp = exp;
1681 STRIP_TYPE_NOPS (exp);
1682
1683 if (TREE_NO_WARNING (orig_exp))
1684 TREE_NO_WARNING (exp) = 1;
1685
1686 if (INTEGRAL_TYPE_P (type))
1687 return perform_integral_promotions (exp);
1688
1689 if (code == VOID_TYPE)
1690 {
1691 error ("void value not ignored as it ought to be");
1692 return error_mark_node;
1693 }
1694 return exp;
1695}
1696
1697/* Look up COMPONENT in a structure or union DECL.
1698
1699 If the component name is not found, returns NULL_TREE. Otherwise,
1700 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1701 stepping down the chain to the component, which is in the last
1702 TREE_VALUE of the list. Normally the list is of length one, but if
1703 the component is embedded within (nested) anonymous structures or
1704 unions, the list steps down the chain to the component. */
1705
1706static tree
1707lookup_field (tree decl, tree component)
1708{
1709 tree type = TREE_TYPE (decl);
1710 tree field;
1711
1712 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1713 to the field elements. Use a binary search on this array to quickly
1714 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1715 will always be set for structures which have many elements. */
1716
1717 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1718 {
1719 int bot, top, half;
1720 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1721
1722 field = TYPE_FIELDS (type);
1723 bot = 0;
1724 top = TYPE_LANG_SPECIFIC (type)->s->len;
1725 while (top - bot > 1)
1726 {
1727 half = (top - bot + 1) >> 1;
1728 field = field_array[bot+half];
1729
1730 if (DECL_NAME (field) == NULL_TREE)
1731 {
1732 /* Step through all anon unions in linear fashion. */
1733 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1734 {
1735 field = field_array[bot++];
1736 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1737 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1738 {
1739 tree anon = lookup_field (field, component);
1740
1741 if (anon)
1742 return tree_cons (NULL_TREE, field, anon);
1743 }
1744 }
1745
1746 /* Entire record is only anon unions. */
1747 if (bot > top)
1748 return NULL_TREE;
1749
1750 /* Restart the binary search, with new lower bound. */
1751 continue;
1752 }
1753
1754 if (DECL_NAME (field) == component)
1755 break;
1756 if (DECL_NAME (field) < component)
1757 bot += half;
1758 else
1759 top = bot + half;
1760 }
1761
1762 if (DECL_NAME (field_array[bot]) == component)
1763 field = field_array[bot];
1764 else if (DECL_NAME (field) != component)
1765 return NULL_TREE;
1766 }
1767 else
1768 {
1769 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1770 {
1771 if (DECL_NAME (field) == NULL_TREE
1772 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1773 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1774 {
1775 tree anon = lookup_field (field, component);
1776
1777 if (anon)
1778 return tree_cons (NULL_TREE, field, anon);
1779 }
1780
1781 if (DECL_NAME (field) == component)
1782 break;
1783 }
1784
1785 if (field == NULL_TREE)
1786 return NULL_TREE;
1787 }
1788
1789 return tree_cons (NULL_TREE, field, NULL_TREE);
1790}
1791
1792/* Make an expression to refer to the COMPONENT field of
1793 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1794
1795tree
1796build_component_ref (tree datum, tree component)
1797{
1798 tree type = TREE_TYPE (datum);
1799 enum tree_code code = TREE_CODE (type);
1800 tree field = NULL;
1801 tree ref;
1802
1803 if (!objc_is_public (datum, component))
1804 return error_mark_node;
1805
1806 /* See if there is a field or component with name COMPONENT. */
1807
1808 if (code == RECORD_TYPE || code == UNION_TYPE)
1809 {
1810 if (!COMPLETE_TYPE_P (type))
1811 {
1812 c_incomplete_type_error (NULL_TREE, type);
1813 return error_mark_node;
1814 }
1815
1816 field = lookup_field (datum, component);
1817
1818 if (!field)
1819 {
1820 error ("%qT has no member named %qE", type, component);
1821 return error_mark_node;
1822 }
1823
1824 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1825 This might be better solved in future the way the C++ front
1826 end does it - by giving the anonymous entities each a
1827 separate name and type, and then have build_component_ref
1828 recursively call itself. We can't do that here. */
1829 do
1830 {
1831 tree subdatum = TREE_VALUE (field);
1832 int quals;
1833 tree subtype;
1834
1835 if (TREE_TYPE (subdatum) == error_mark_node)
1836 return error_mark_node;
1837
1838 quals = TYPE_QUALS (strip_array_types (TREE_TYPE (subdatum)));
1839 quals |= TYPE_QUALS (TREE_TYPE (datum));
1840 subtype = c_build_qualified_type (TREE_TYPE (subdatum), quals);
1841
1842 ref = build3 (COMPONENT_REF, subtype, datum, subdatum,
1843 NULL_TREE);
1844 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1845 TREE_READONLY (ref) = 1;
1846 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1847 TREE_THIS_VOLATILE (ref) = 1;
1848
1849 if (TREE_DEPRECATED (subdatum))
1850 warn_deprecated_use (subdatum);
1851
1852 datum = ref;
1853
1854 field = TREE_CHAIN (field);
1855 }
1856 while (field);
1857
1858 return ref;
1859 }
1860 else if (code != ERROR_MARK)
1861 error ("request for member %qE in something not a structure or union",
1862 component);
1863
1864 return error_mark_node;
1865}
1866
1867/* Given an expression PTR for a pointer, return an expression
1868 for the value pointed to.
1869 ERRORSTRING is the name of the operator to appear in error messages. */
1870
1871tree
1872build_indirect_ref (tree ptr, const char *errorstring)
1873{
1874 tree pointer = default_conversion (ptr);
1875 tree type = TREE_TYPE (pointer);
1876
1877 if (TREE_CODE (type) == POINTER_TYPE)
1878 {
1879 if (TREE_CODE (pointer) == CONVERT_EXPR
1880 || TREE_CODE (pointer) == NOP_EXPR
1881 || TREE_CODE (pointer) == VIEW_CONVERT_EXPR)
1882 {
1883 /* If a warning is issued, mark it to avoid duplicates from
1884 the backend. This only needs to be done at
1885 warn_strict_aliasing > 2. */
1886 if (warn_strict_aliasing > 2)
1887 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (pointer, 0)),
1888 type, TREE_OPERAND (pointer, 0)))
1889 TREE_NO_WARNING (pointer) = 1;
1890 }
1891
1892 if (TREE_CODE (pointer) == ADDR_EXPR
1893 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1894 == TREE_TYPE (type)))
1895 return TREE_OPERAND (pointer, 0);
1896 else
1897 {
1898 tree t = TREE_TYPE (type);
1899 tree ref;
1900
1901 ref = build1 (INDIRECT_REF, t, pointer);
1902
1903 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1904 {
1905 error ("dereferencing pointer to incomplete type");
1906 return error_mark_node;
1907 }
1908 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1909 warning (0, "dereferencing %<void *%> pointer");
1910
1911 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1912 so that we get the proper error message if the result is used
1913 to assign to. Also, &* is supposed to be a no-op.
1914 And ANSI C seems to specify that the type of the result
1915 should be the const type. */
1916 /* A de-reference of a pointer to const is not a const. It is valid
1917 to change it via some other pointer. */
1918 TREE_READONLY (ref) = TYPE_READONLY (t);
1919 TREE_SIDE_EFFECTS (ref)
1920 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1921 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1922 return ref;
1923 }
1924 }
1925 else if (TREE_CODE (pointer) != ERROR_MARK)
1926 error ("invalid type argument of %qs (have %qT)", errorstring, type);
1927 return error_mark_node;
1928}
1929
1930/* This handles expressions of the form "a[i]", which denotes
1931 an array reference.
1932
1933 This is logically equivalent in C to *(a+i), but we may do it differently.
1934 If A is a variable or a member, we generate a primitive ARRAY_REF.
1935 This avoids forcing the array out of registers, and can work on
1936 arrays that are not lvalues (for example, members of structures returned
1937 by functions). */
1938
1939tree
1940build_array_ref (tree array, tree index)
1941{
1942 bool swapped = false;
1943 if (TREE_TYPE (array) == error_mark_node
1944 || TREE_TYPE (index) == error_mark_node)
1945 return error_mark_node;
1946
1947 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
1948 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
1949 {
1950 tree temp;
1951 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
1952 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
1953 {
1954 error ("subscripted value is neither array nor pointer");
1955 return error_mark_node;
1956 }
1957 temp = array;
1958 array = index;
1959 index = temp;
1960 swapped = true;
1961 }
1962
1963 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
1964 {
1965 error ("array subscript is not an integer");
1966 return error_mark_node;
1967 }
1968
1969 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
1970 {
1971 error ("subscripted value is pointer to function");
1972 return error_mark_node;
1973 }
1974
1975 /* ??? Existing practice has been to warn only when the char
1976 index is syntactically the index, not for char[array]. */
1977 if (!swapped)
1978 warn_array_subscript_with_type_char (index);
1979
1980 /* Apply default promotions *after* noticing character types. */
1981 index = default_conversion (index);
1982
1983 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
1984
1985 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1986 {
1987 tree rval, type;
1988
1989 /* An array that is indexed by a non-constant
1990 cannot be stored in a register; we must be able to do
1991 address arithmetic on its address.
1992 Likewise an array of elements of variable size. */
1993 if (TREE_CODE (index) != INTEGER_CST
1994 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1995 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1996 {
1997 if (!c_mark_addressable (array))
1998 return error_mark_node;
1999 }
2000 /* An array that is indexed by a constant value which is not within
2001 the array bounds cannot be stored in a register either; because we
2002 would get a crash in store_bit_field/extract_bit_field when trying
2003 to access a non-existent part of the register. */
2004 if (TREE_CODE (index) == INTEGER_CST
2005 && TYPE_DOMAIN (TREE_TYPE (array))
2006 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
2007 {
2008 if (!c_mark_addressable (array))
2009 return error_mark_node;
2010 }
2011
2012 if (pedantic)
2013 {
2014 tree foo = array;
2015 while (TREE_CODE (foo) == COMPONENT_REF)
2016 foo = TREE_OPERAND (foo, 0);
2017 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
2018 pedwarn ("ISO C forbids subscripting %<register%> array");
2019 else if (!flag_isoc99 && !lvalue_p (foo))
2020 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
2021 }
2022
2023 type = TREE_TYPE (TREE_TYPE (array));
2024 if (TREE_CODE (type) != ARRAY_TYPE)
2025 type = TYPE_MAIN_VARIANT (type);
2026 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
2027 /* Array ref is const/volatile if the array elements are
2028 or if the array is. */
2029 TREE_READONLY (rval)
2030 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
2031 | TREE_READONLY (array));
2032 TREE_SIDE_EFFECTS (rval)
2033 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2034 | TREE_SIDE_EFFECTS (array));
2035 TREE_THIS_VOLATILE (rval)
2036 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2037 /* This was added by rms on 16 Nov 91.
2038 It fixes vol struct foo *a; a->elts[1]
2039 in an inline function.
2040 Hope it doesn't break something else. */
2041 | TREE_THIS_VOLATILE (array));
2042 return require_complete_type (fold (rval));
2043 }
2044 else
2045 {
2046 tree ar = default_conversion (array);
2047
2048 if (ar == error_mark_node)
2049 return ar;
2050
2051 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
2052 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
2053
2054 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
2055 "array indexing");
2056 }
2057}
2058
2059/* Build an external reference to identifier ID. FUN indicates
2060 whether this will be used for a function call. LOC is the source
2061 location of the identifier. */
2062tree
2063build_external_ref (tree id, int fun, location_t loc)
2064{
2065 tree ref;
2066 tree decl = lookup_name (id);
2067
2068 /* In Objective-C, an instance variable (ivar) may be preferred to
2069 whatever lookup_name() found. */
2070 decl = objc_lookup_ivar (decl, id);
2071
2072 if (decl && decl != error_mark_node)
2073 ref = decl;
2074 else if (fun)
2075 /* Implicit function declaration. */
2076 ref = implicitly_declare (id);
2077 else if (decl == error_mark_node)
2078 /* Don't complain about something that's already been
2079 complained about. */
2080 return error_mark_node;
2081 else
2082 {
2083 undeclared_variable (id, loc);
2084 return error_mark_node;
2085 }
2086
2087 if (TREE_TYPE (ref) == error_mark_node)
2088 return error_mark_node;
2089
2090 if (TREE_DEPRECATED (ref))
2091 warn_deprecated_use (ref);
2092
2093 if (!skip_evaluation)
2094 assemble_external (ref);
2095 TREE_USED (ref) = 1;
2096
2097 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
2098 {
2099 if (!in_sizeof && !in_typeof)
2100 C_DECL_USED (ref) = 1;
2101 else if (DECL_INITIAL (ref) == 0
2102 && DECL_EXTERNAL (ref)
2103 && !TREE_PUBLIC (ref))
2104 record_maybe_used_decl (ref);
2105 }
2106
2107 if (TREE_CODE (ref) == CONST_DECL)
2108 {
2109 used_types_insert (TREE_TYPE (ref));
2110 ref = DECL_INITIAL (ref);
2111 TREE_CONSTANT (ref) = 1;
2112 TREE_INVARIANT (ref) = 1;
2113 }
2114 else if (current_function_decl != 0
2115 && !DECL_FILE_SCOPE_P (current_function_decl)
2116 && (TREE_CODE (ref) == VAR_DECL
2117 || TREE_CODE (ref) == PARM_DECL
2118 || TREE_CODE (ref) == FUNCTION_DECL))
2119 {
2120 tree context = decl_function_context (ref);
2121
2122 if (context != 0 && context != current_function_decl)
2123 DECL_NONLOCAL (ref) = 1;
2124 }
2125 /* C99 6.7.4p3: An inline definition of a function with external
2126 linkage ... shall not contain a reference to an identifier with
2127 internal linkage. */
2128 else if (current_function_decl != 0
2129 && DECL_DECLARED_INLINE_P (current_function_decl)
2130 && DECL_EXTERNAL (current_function_decl)
2131 && VAR_OR_FUNCTION_DECL_P (ref)
2132 && DECL_FILE_SCOPE_P (ref)
2133 && pedantic
2134 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref))
2135 && ! TREE_PUBLIC (ref))
2136 pedwarn ("%H%qD is static but used in inline function %qD "
2137 "which is not static", &loc, ref, current_function_decl);
2138
2139 return ref;
2140}
2141
2142/* Record details of decls possibly used inside sizeof or typeof. */
2143struct maybe_used_decl
2144{
2145 /* The decl. */
2146 tree decl;
2147 /* The level seen at (in_sizeof + in_typeof). */
2148 int level;
2149 /* The next one at this level or above, or NULL. */
2150 struct maybe_used_decl *next;
2151};
2152
2153static struct maybe_used_decl *maybe_used_decls;
2154
2155/* Record that DECL, an undefined static function reference seen
2156 inside sizeof or typeof, might be used if the operand of sizeof is
2157 a VLA type or the operand of typeof is a variably modified
2158 type. */
2159
2160static void
2161record_maybe_used_decl (tree decl)
2162{
2163 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
2164 t->decl = decl;
2165 t->level = in_sizeof + in_typeof;
2166 t->next = maybe_used_decls;
2167 maybe_used_decls = t;
2168}
2169
2170/* Pop the stack of decls possibly used inside sizeof or typeof. If
2171 USED is false, just discard them. If it is true, mark them used
2172 (if no longer inside sizeof or typeof) or move them to the next
2173 level up (if still inside sizeof or typeof). */
2174
2175void
2176pop_maybe_used (bool used)
2177{
2178 struct maybe_used_decl *p = maybe_used_decls;
2179 int cur_level = in_sizeof + in_typeof;
2180 while (p && p->level > cur_level)
2181 {
2182 if (used)
2183 {
2184 if (cur_level == 0)
2185 C_DECL_USED (p->decl) = 1;
2186 else
2187 p->level = cur_level;
2188 }
2189 p = p->next;
2190 }
2191 if (!used || cur_level == 0)
2192 maybe_used_decls = p;
2193}
2194
2195/* Return the result of sizeof applied to EXPR. */
2196
2197struct c_expr
2198c_expr_sizeof_expr (struct c_expr expr)
2199{
2200 struct c_expr ret;
2201 if (expr.value == error_mark_node)
2202 {
2203 ret.value = error_mark_node;
2204 ret.original_code = ERROR_MARK;
2205 pop_maybe_used (false);
2206 }
2207 else
2208 {
2209 ret.value = c_sizeof (TREE_TYPE (expr.value));
2210 ret.original_code = ERROR_MARK;
2211 if (c_vla_type_p (TREE_TYPE (expr.value)))
2212 {
2213 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */
2214 ret.value = build2 (COMPOUND_EXPR, TREE_TYPE (ret.value), expr.value, ret.value);
2215 }
2216 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
2217 }
2218 return ret;
2219}
2220
2221/* Return the result of sizeof applied to T, a structure for the type
2222 name passed to sizeof (rather than the type itself). */
2223
2224struct c_expr
2225c_expr_sizeof_type (struct c_type_name *t)
2226{
2227 tree type;
2228 struct c_expr ret;
2229 type = groktypename (t);
2230 ret.value = c_sizeof (type);
2231 ret.original_code = ERROR_MARK;
2232 pop_maybe_used (type != error_mark_node
2233 ? C_TYPE_VARIABLE_SIZE (type) : false);
2234 return ret;
2235}
2236
2237/* Build a function call to function FUNCTION with parameters PARAMS.
2238 PARAMS is a list--a chain of TREE_LIST nodes--in which the
2239 TREE_VALUE of each node is a parameter-expression.
2240 FUNCTION's data type may be a function type or a pointer-to-function. */
2241
2242tree
2243build_function_call (tree function, tree params)
2244{
2245 tree fntype, fundecl = 0;
2246 tree coerced_params;
2247 tree name = NULL_TREE, result;
2248 tree tem;
2249
2250 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2251 STRIP_TYPE_NOPS (function);
2252
2253 /* Convert anything with function type to a pointer-to-function. */
2254 if (TREE_CODE (function) == FUNCTION_DECL)
2255 {
2256 /* Implement type-directed function overloading for builtins.
2257 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
2258 handle all the type checking. The result is a complete expression
2259 that implements this function call. */
2260 tem = resolve_overloaded_builtin (function, params);
2261 if (tem)
2262 return tem;
2263
2264 name = DECL_NAME (function);
2265 fundecl = function;
2266 }
2267 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE)
2268 function = function_to_pointer_conversion (function);
2269
2270 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2271 expressions, like those used for ObjC messenger dispatches. */
2272 function = objc_rewrite_function_call (function, params);
2273
2274 fntype = TREE_TYPE (function);
2275
2276 if (TREE_CODE (fntype) == ERROR_MARK)
2277 return error_mark_node;
2278
2279 if (!(TREE_CODE (fntype) == POINTER_TYPE
2280 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2281 {
2282 error ("called object %qE is not a function", function);
2283 return error_mark_node;
2284 }
2285
2286 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2287 current_function_returns_abnormally = 1;
2288
2289 /* fntype now gets the type of function pointed to. */
2290 fntype = TREE_TYPE (fntype);
2291
2292 /* Check that the function is called through a compatible prototype.
2293 If it is not, replace the call by a trap, wrapped up in a compound
2294 expression if necessary. This has the nice side-effect to prevent
2295 the tree-inliner from generating invalid assignment trees which may
2296 blow up in the RTL expander later. */
2297 if ((TREE_CODE (function) == NOP_EXPR
2298 || TREE_CODE (function) == CONVERT_EXPR)
2299 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2300 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2301 && !comptypes (fntype, TREE_TYPE (tem)))
2302 {
2303 tree return_type = TREE_TYPE (fntype);
2304 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
2305 NULL_TREE);
2306
2307 /* This situation leads to run-time undefined behavior. We can't,
2308 therefore, simply error unless we can prove that all possible
2309 executions of the program must execute the code. */
2310 warning (0, "function called through a non-compatible type");
2311
2312 /* We can, however, treat "undefined" any way we please.
2313 Call abort to encourage the user to fix the program. */
2314 inform ("if this code is reached, the program will abort");
2315
2316 if (VOID_TYPE_P (return_type))
2317 return trap;
2318 else
2319 {
2320 tree rhs;
2321
2322 if (AGGREGATE_TYPE_P (return_type))
2323 rhs = build_compound_literal (return_type,
2324 build_constructor (return_type, 0));
2325 else
2326 rhs = fold_convert (return_type, integer_zero_node);
2327
2328 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
2329 }
2330 }
2331
2332 /* Convert the parameters to the types declared in the
2333 function prototype, or apply default promotions. */
2334
2335 coerced_params
2336 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl);
2337
2338 if (coerced_params == error_mark_node)
2339 return error_mark_node;
2340
2341 /* Check that the arguments to the function are valid. */
2342
2343 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2344 TYPE_ARG_TYPES (fntype));
2345
2346 if (require_constant_value)
2347 {
2348 result = fold_build3_initializer (CALL_EXPR, TREE_TYPE (fntype),
2349 function, coerced_params, NULL_TREE);
2350
2351 if (TREE_CONSTANT (result)
2352 && (name == NULL_TREE
2353 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
2354 pedwarn_init ("initializer element is not constant");
2355 }
2356 else
2357 result = fold_build3 (CALL_EXPR, TREE_TYPE (fntype),
2358 function, coerced_params, NULL_TREE);
2359
2360 if (VOID_TYPE_P (TREE_TYPE (result)))
2361 return result;
2362 return require_complete_type (result);
2363}
2364
2365/* Convert the argument expressions in the list VALUES
2366 to the types in the list TYPELIST. The result is a list of converted
2367 argument expressions, unless there are too few arguments in which
2368 case it is error_mark_node.
2369
2370 If TYPELIST is exhausted, or when an element has NULL as its type,
2371 perform the default conversions.
2372
2373 PARMLIST is the chain of parm decls for the function being called.
2374 It may be 0, if that info is not available.
2375 It is used only for generating error messages.
2376
2377 FUNCTION is a tree for the called function. It is used only for
2378 error messages, where it is formatted with %qE.
2379
2380 This is also where warnings about wrong number of args are generated.
2381
2382 Both VALUES and the returned value are chains of TREE_LIST nodes
2383 with the elements of the list in the TREE_VALUE slots of those nodes. */
2384
2385static tree
2386convert_arguments (tree typelist, tree values, tree function, tree fundecl)
2387{
2388 tree typetail, valtail;
2389 tree result = NULL;
2390 int parmnum;
2391 tree selector;
2392
2393 /* Change pointer to function to the function itself for
2394 diagnostics. */
2395 if (TREE_CODE (function) == ADDR_EXPR
2396 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2397 function = TREE_OPERAND (function, 0);
2398
2399 /* Handle an ObjC selector specially for diagnostics. */
2400 selector = objc_message_selector ();
2401
2402 /* Scan the given expressions and types, producing individual
2403 converted arguments and pushing them on RESULT in reverse order. */
2404
2405 for (valtail = values, typetail = typelist, parmnum = 0;
2406 valtail;
2407 valtail = TREE_CHAIN (valtail), parmnum++)
2408 {
2409 tree type = typetail ? TREE_VALUE (typetail) : 0;
2410 tree val = TREE_VALUE (valtail);
2411 tree rname = function;
2412 int argnum = parmnum + 1;
2413 const char *invalid_func_diag;
2414
2415 if (type == void_type_node)
2416 {
2417 error ("too many arguments to function %qE", function);
2418 break;
2419 }
2420
2421 if (selector && argnum > 2)
2422 {
2423 rname = selector;
2424 argnum -= 2;
2425 }
2426
2427 STRIP_TYPE_NOPS (val);
2428
2429 val = require_complete_type (val);
2430
2431 if (type != 0)
2432 {
2433 /* Formal parm type is specified by a function prototype. */
2434 tree parmval;
2435
2436 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2437 {
2438 error ("type of formal parameter %d is incomplete", parmnum + 1);
2439 parmval = val;
2440 }
2441 else
2442 {
2443 /* Optionally warn about conversions that
2444 differ from the default conversions. */
2445 if (warn_conversion || warn_traditional)
2446 {
2447 unsigned int formal_prec = TYPE_PRECISION (type);
2448
2449 if (INTEGRAL_TYPE_P (type)
2450 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2451 warning (0, "passing argument %d of %qE as integer "
2452 "rather than floating due to prototype",
2453 argnum, rname);
2454 if (INTEGRAL_TYPE_P (type)
2455 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2456 warning (0, "passing argument %d of %qE as integer "
2457 "rather than complex due to prototype",
2458 argnum, rname);
2459 else if (TREE_CODE (type) == COMPLEX_TYPE
2460 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2461 warning (0, "passing argument %d of %qE as complex "
2462 "rather than floating due to prototype",
2463 argnum, rname);
2464 else if (TREE_CODE (type) == REAL_TYPE
2465 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2466 warning (0, "passing argument %d of %qE as floating "
2467 "rather than integer due to prototype",
2468 argnum, rname);
2469 else if (TREE_CODE (type) == COMPLEX_TYPE
2470 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2471 warning (0, "passing argument %d of %qE as complex "
2472 "rather than integer due to prototype",
2473 argnum, rname);
2474 else if (TREE_CODE (type) == REAL_TYPE
2475 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2476 warning (0, "passing argument %d of %qE as floating "
2477 "rather than complex due to prototype",
2478 argnum, rname);
2479 /* ??? At some point, messages should be written about
2480 conversions between complex types, but that's too messy
2481 to do now. */
2482 else if (TREE_CODE (type) == REAL_TYPE
2483 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2484 {
2485 /* Warn if any argument is passed as `float',
2486 since without a prototype it would be `double'. */
2487 if (formal_prec == TYPE_PRECISION (float_type_node)
2488 && type != dfloat32_type_node)
2489 warning (0, "passing argument %d of %qE as %<float%> "
2490 "rather than %<double%> due to prototype",
2491 argnum, rname);
2492
2493 /* Warn if mismatch between argument and prototype
2494 for decimal float types. Warn of conversions with
2495 binary float types and of precision narrowing due to
2496 prototype. */
2497 else if (type != TREE_TYPE (val)
2498 && (type == dfloat32_type_node
2499 || type == dfloat64_type_node
2500 || type == dfloat128_type_node
2501 || TREE_TYPE (val) == dfloat32_type_node
2502 || TREE_TYPE (val) == dfloat64_type_node
2503 || TREE_TYPE (val) == dfloat128_type_node)
2504 && (formal_prec
2505 <= TYPE_PRECISION (TREE_TYPE (val))
2506 || (type == dfloat128_type_node
2507 && (TREE_TYPE (val)
2508 != dfloat64_type_node
2509 && (TREE_TYPE (val)
2510 != dfloat32_type_node)))
2511 || (type == dfloat64_type_node
2512 && (TREE_TYPE (val)
2513 != dfloat32_type_node))))
2514 warning (0, "passing argument %d of %qE as %qT "
2515 "rather than %qT due to prototype",
2516 argnum, rname, type, TREE_TYPE (val));
2517
2518 }
2519 /* Detect integer changing in width or signedness.
2520 These warnings are only activated with
2521 -Wconversion, not with -Wtraditional. */
2522 else if (warn_conversion && INTEGRAL_TYPE_P (type)
2523 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2524 {
2525 tree would_have_been = default_conversion (val);
2526 tree type1 = TREE_TYPE (would_have_been);
2527
2528 if (TREE_CODE (type) == ENUMERAL_TYPE
2529 && (TYPE_MAIN_VARIANT (type)
2530 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2531 /* No warning if function asks for enum
2532 and the actual arg is that enum type. */
2533 ;
2534 else if (formal_prec != TYPE_PRECISION (type1))
2535 warning (OPT_Wconversion, "passing argument %d of %qE "
2536 "with different width due to prototype",
2537 argnum, rname);
2538 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2539 ;
2540 /* Don't complain if the formal parameter type
2541 is an enum, because we can't tell now whether
2542 the value was an enum--even the same enum. */
2543 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2544 ;
2545 else if (TREE_CODE (val) == INTEGER_CST
2546 && int_fits_type_p (val, type))
2547 /* Change in signedness doesn't matter
2548 if a constant value is unaffected. */
2549 ;
2550 /* If the value is extended from a narrower
2551 unsigned type, it doesn't matter whether we
2552 pass it as signed or unsigned; the value
2553 certainly is the same either way. */
2554 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2555 && TYPE_UNSIGNED (TREE_TYPE (val)))
2556 ;
2557 else if (TYPE_UNSIGNED (type))
2558 warning (OPT_Wconversion, "passing argument %d of %qE "
2559 "as unsigned due to prototype",
2560 argnum, rname);
2561 else
2562 warning (OPT_Wconversion, "passing argument %d of %qE "
2563 "as signed due to prototype", argnum, rname);
2564 }
2565 }
2566
2567 parmval = convert_for_assignment (type, val, ic_argpass,
2568 fundecl, function,
2569 parmnum + 1);
2570
2571 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2572 && INTEGRAL_TYPE_P (type)
2573 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2574 parmval = default_conversion (parmval);
2575 }
2576 result = tree_cons (NULL_TREE, parmval, result);
2577 }
2578 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2579 && (TYPE_PRECISION (TREE_TYPE (val))
2580 < TYPE_PRECISION (double_type_node))
2581 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (val))))
2582 /* Convert `float' to `double'. */
2583 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2584 else if ((invalid_func_diag =
2585 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
2586 {
2587 error (invalid_func_diag, "");
2588 return error_mark_node;
2589 }
2590 else
2591 /* Convert `short' and `char' to full-size `int'. */
2592 result = tree_cons (NULL_TREE, default_conversion (val), result);
2593
2594 if (typetail)
2595 typetail = TREE_CHAIN (typetail);
2596 }
2597
2598 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2599 {
2600 error ("too few arguments to function %qE", function);
2601 return error_mark_node;
2602 }
2603
2604 return nreverse (result);
2605}
2606
2607/* This is the entry point used by the parser to build unary operators
2608 in the input. CODE, a tree_code, specifies the unary operator, and
2609 ARG is the operand. For unary plus, the C parser currently uses
2610 CONVERT_EXPR for code. */
2611
2612struct c_expr
2613parser_build_unary_op (enum tree_code code, struct c_expr arg)
2614{
2615 struct c_expr result;
2616
2617 result.original_code = ERROR_MARK;
2618 result.value = build_unary_op (code, arg.value, 0);
2619
2620 if (TREE_OVERFLOW_P (result.value) && !TREE_OVERFLOW_P (arg.value))
2621 overflow_warning (result.value);
2622
2623 return result;
2624}
2625
2626/* This is the entry point used by the parser to build binary operators
2627 in the input. CODE, a tree_code, specifies the binary operator, and
2628 ARG1 and ARG2 are the operands. In addition to constructing the
2629 expression, we check for operands that were written with other binary
2630 operators in a way that is likely to confuse the user. */
2631
2632struct c_expr
2633parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2634 struct c_expr arg2)
2635{
2636 struct c_expr result;
2637
2638 enum tree_code code1 = arg1.original_code;
2639 enum tree_code code2 = arg2.original_code;
2640
2641 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2642 result.original_code = code;
2643
2644 if (TREE_CODE (result.value) == ERROR_MARK)
2645 return result;
2646
2647 /* Check for cases such as x+y<<z which users are likely
2648 to misinterpret. */
2649 if (warn_parentheses)
2650 warn_about_parentheses (code, code1, code2);
2651
2652 /* Warn about comparisons against string literals, with the exception
2653 of testing for equality or inequality of a string literal with NULL. */
2654 if (code == EQ_EXPR || code == NE_EXPR)
2655 {
2656 if ((code1 == STRING_CST && !integer_zerop (arg2.value))
2657 || (code2 == STRING_CST && !integer_zerop (arg1.value)))
2658 warning (OPT_Waddress,
2659 "comparison with string literal results in unspecified behaviour");
2660 }
2661 else if (TREE_CODE_CLASS (code) == tcc_comparison
2662 && (code1 == STRING_CST || code2 == STRING_CST))
2663 warning (OPT_Waddress,
2664 "comparison with string literal results in unspecified behaviour");
2665
2666 if (TREE_OVERFLOW_P (result.value)
2667 && !TREE_OVERFLOW_P (arg1.value)
2668 && !TREE_OVERFLOW_P (arg2.value))
2669 overflow_warning (result.value);
2670
2671 return result;
2672}
2673
2674/* Return a tree for the difference of pointers OP0 and OP1.
2675 The resulting tree has type int. */
2676
2677static tree
2678pointer_diff (tree op0, tree op1)
2679{
2680 tree restype = ptrdiff_type_node;
2681
2682 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2683 tree con0, con1, lit0, lit1;
2684 tree orig_op1 = op1;
2685
2686 if (pedantic || warn_pointer_arith)
2687 {
2688 if (TREE_CODE (target_type) == VOID_TYPE)
2689 pedwarn ("pointer of type %<void *%> used in subtraction");
2690 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2691 pedwarn ("pointer to a function used in subtraction");
2692 }
2693
2694 /* If the conversion to ptrdiff_type does anything like widening or
2695 converting a partial to an integral mode, we get a convert_expression
2696 that is in the way to do any simplifications.
2697 (fold-const.c doesn't know that the extra bits won't be needed.
2698 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2699 different mode in place.)
2700 So first try to find a common term here 'by hand'; we want to cover
2701 at least the cases that occur in legal static initializers. */
2702 if ((TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == CONVERT_EXPR)
2703 && (TYPE_PRECISION (TREE_TYPE (op0))
2704 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
2705 con0 = TREE_OPERAND (op0, 0);
2706 else
2707 con0 = op0;
2708 if ((TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == CONVERT_EXPR)
2709 && (TYPE_PRECISION (TREE_TYPE (op1))
2710 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))))
2711 con1 = TREE_OPERAND (op1, 0);
2712 else
2713 con1 = op1;
2714
2715 if (TREE_CODE (con0) == PLUS_EXPR)
2716 {
2717 lit0 = TREE_OPERAND (con0, 1);
2718 con0 = TREE_OPERAND (con0, 0);
2719 }
2720 else
2721 lit0 = integer_zero_node;
2722
2723 if (TREE_CODE (con1) == PLUS_EXPR)
2724 {
2725 lit1 = TREE_OPERAND (con1, 1);
2726 con1 = TREE_OPERAND (con1, 0);
2727 }
2728 else
2729 lit1 = integer_zero_node;
2730
2731 if (operand_equal_p (con0, con1, 0))
2732 {
2733 op0 = lit0;
2734 op1 = lit1;
2735 }
2736
2737
2738 /* First do the subtraction as integers;
2739 then drop through to build the divide operator.
2740 Do not do default conversions on the minus operator
2741 in case restype is a short type. */
2742
2743 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2744 convert (restype, op1), 0);
2745 /* This generates an error if op1 is pointer to incomplete type. */
2746 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2747 error ("arithmetic on pointer to an incomplete type");
2748
2749 /* This generates an error if op0 is pointer to incomplete type. */
2750 op1 = c_size_in_bytes (target_type);
2751
2752 /* Divide by the size, in easiest possible way. */
2753 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2754}
2755
2756/* Construct and perhaps optimize a tree representation
2757 for a unary operation. CODE, a tree_code, specifies the operation
2758 and XARG is the operand.
2759 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2760 the default promotions (such as from short to int).
2761 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2762 allows non-lvalues; this is only used to handle conversion of non-lvalue
2763 arrays to pointers in C99. */
2764
2765tree
2766build_unary_op (enum tree_code code, tree xarg, int flag)
2767{
2768 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2769 tree arg = xarg;
2770 tree argtype = 0;
2771 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2772 tree val;
2773 int noconvert = flag;
2774 const char *invalid_op_diag;
2775
2776 if (typecode == ERROR_MARK)
2777 return error_mark_node;
2778 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2779 typecode = INTEGER_TYPE;
2780
2781 if ((invalid_op_diag
2782 = targetm.invalid_unary_op (code, TREE_TYPE (xarg))))
2783 {
2784 error (invalid_op_diag, "");
2785 return error_mark_node;
2786 }
2787
2788 switch (code)
2789 {
2790 case CONVERT_EXPR:
2791 /* This is used for unary plus, because a CONVERT_EXPR
2792 is enough to prevent anybody from looking inside for
2793 associativity, but won't generate any code. */
2794 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2795 || typecode == COMPLEX_TYPE
2796 || typecode == VECTOR_TYPE))
2797 {
2798 error ("wrong type argument to unary plus");
2799 return error_mark_node;
2800 }
2801 else if (!noconvert)
2802 arg = default_conversion (arg);
2803 arg = non_lvalue (arg);
2804 break;
2805
2806 case NEGATE_EXPR:
2807 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2808 || typecode == COMPLEX_TYPE
2809 || typecode == VECTOR_TYPE))
2810 {
2811 error ("wrong type argument to unary minus");
2812 return error_mark_node;
2813 }
2814 else if (!noconvert)
2815 arg = default_conversion (arg);
2816 break;
2817
2818 case BIT_NOT_EXPR:
2819 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2820 {
2821 if (!noconvert)
2822 arg = default_conversion (arg);
2823 }
2824 else if (typecode == COMPLEX_TYPE)
2825 {
2826 code = CONJ_EXPR;
2827 if (pedantic)
2828 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2829 if (!noconvert)
2830 arg = default_conversion (arg);
2831 }
2832 else
2833 {
2834 error ("wrong type argument to bit-complement");
2835 return error_mark_node;
2836 }
2837 break;
2838
2839 case ABS_EXPR:
2840 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2841 {
2842 error ("wrong type argument to abs");
2843 return error_mark_node;
2844 }
2845 else if (!noconvert)
2846 arg = default_conversion (arg);
2847 break;
2848
2849 case CONJ_EXPR:
2850 /* Conjugating a real value is a no-op, but allow it anyway. */
2851 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2852 || typecode == COMPLEX_TYPE))
2853 {
2854 error ("wrong type argument to conjugation");
2855 return error_mark_node;
2856 }
2857 else if (!noconvert)
2858 arg = default_conversion (arg);
2859 break;
2860
2861 case TRUTH_NOT_EXPR:
2862 if (typecode != INTEGER_TYPE
2863 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2864 && typecode != COMPLEX_TYPE)
2865 {
2866 error ("wrong type argument to unary exclamation mark");
2867 return error_mark_node;
2868 }
2869 arg = c_objc_common_truthvalue_conversion (arg);
2870 return invert_truthvalue (arg);
2871
2872 case REALPART_EXPR:
2873 if (TREE_CODE (arg) == COMPLEX_CST)
2874 return TREE_REALPART (arg);
2875 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2876 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2877 else
2878 return arg;
2879
2880 case IMAGPART_EXPR:
2881 if (TREE_CODE (arg) == COMPLEX_CST)
2882 return TREE_IMAGPART (arg);
2883 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2884 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2885 else
2886 return convert (TREE_TYPE (arg), integer_zero_node);
2887
2888 case PREINCREMENT_EXPR:
2889 case POSTINCREMENT_EXPR:
2890 case PREDECREMENT_EXPR:
2891 case POSTDECREMENT_EXPR:
2892
2893 /* Increment or decrement the real part of the value,
2894 and don't change the imaginary part. */
2895 if (typecode == COMPLEX_TYPE)
2896 {
2897 tree real, imag;
2898
2899 if (pedantic)
2900 pedwarn ("ISO C does not support %<++%> and %<--%>"
2901 " on complex types");
2902
2903 arg = stabilize_reference (arg);
2904 real = build_unary_op (REALPART_EXPR, arg, 1);
2905 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2906 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2907 build_unary_op (code, real, 1), imag);
2908 }
2909
2910 /* Report invalid types. */
2911
2912 if (typecode != POINTER_TYPE
2913 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2914 {
2915 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2916 error ("wrong type argument to increment");
2917 else
2918 error ("wrong type argument to decrement");
2919
2920 return error_mark_node;
2921 }
2922
2923 {
2924 tree inc;
2925 tree result_type = TREE_TYPE (arg);
2926
2927 arg = get_unwidened (arg, 0);
2928 argtype = TREE_TYPE (arg);
2929
2930 /* Compute the increment. */
2931
2932 if (typecode == POINTER_TYPE)
2933 {
2934 /* If pointer target is an undefined struct,
2935 we just cannot know how to do the arithmetic. */
2936 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2937 {
2938 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2939 error ("increment of pointer to unknown structure");
2940 else
2941 error ("decrement of pointer to unknown structure");
2942 }
2943 else if ((pedantic || warn_pointer_arith)
2944 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2945 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2946 {
2947 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2948 pedwarn ("wrong type argument to increment");
2949 else
2950 pedwarn ("wrong type argument to decrement");
2951 }
2952
2953 inc = c_size_in_bytes (TREE_TYPE (result_type));
2954 }
2955 else
2956 inc = integer_one_node;
2957
2958 inc = convert (argtype, inc);
2959
2960 /* Complain about anything else that is not a true lvalue. */
2961 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2962 || code == POSTINCREMENT_EXPR)
2963 ? lv_increment
2964 : lv_decrement)))
2965 return error_mark_node;
2966
2967 /* Report a read-only lvalue. */
2968 if (TREE_READONLY (arg))
2969 {
2970 readonly_error (arg,
2971 ((code == PREINCREMENT_EXPR
2972 || code == POSTINCREMENT_EXPR)
2973 ? lv_increment : lv_decrement));
2974 return error_mark_node;
2975 }
2976
2977 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2978 val = boolean_increment (code, arg);
2979 else
2980 val = build2 (code, TREE_TYPE (arg), arg, inc);
2981 TREE_SIDE_EFFECTS (val) = 1;
2982 val = convert (result_type, val);
2983 if (TREE_CODE (val) != code)
2984 TREE_NO_WARNING (val) = 1;
2985 return val;
2986 }
2987
2988 case ADDR_EXPR:
2989 /* Note that this operation never does default_conversion. */
2990
2991 /* Let &* cancel out to simplify resulting code. */
2992 if (TREE_CODE (arg) == INDIRECT_REF)
2993 {
2994 /* Don't let this be an lvalue. */
2995 if (lvalue_p (TREE_OPERAND (arg, 0)))
2996 return non_lvalue (TREE_OPERAND (arg, 0));
2997 return TREE_OPERAND (arg, 0);
2998 }
2999
3000 /* For &x[y], return x+y */
3001 if (TREE_CODE (arg) == ARRAY_REF)
3002 {
3003 tree op0 = TREE_OPERAND (arg, 0);
3004 if (!c_mark_addressable (op0))
3005 return error_mark_node;
3006 return build_binary_op (PLUS_EXPR,
3007 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE
3008 ? array_to_pointer_conversion (op0)
3009 : op0),
3010 TREE_OPERAND (arg, 1), 1);
3011 }
3012
3013 /* Anything not already handled and not a true memory reference
3014 or a non-lvalue array is an error. */
3015 else if (typecode != FUNCTION_TYPE && !flag
3016 && !lvalue_or_else (arg, lv_addressof))
3017 return error_mark_node;
3018
3019 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3020 argtype = TREE_TYPE (arg);
3021
3022 /* If the lvalue is const or volatile, merge that into the type
3023 to which the address will point. Note that you can't get a
3024 restricted pointer by taking the address of something, so we
3025 only have to deal with `const' and `volatile' here. */
3026 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
3027 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3028 argtype = c_build_type_variant (argtype,
3029 TREE_READONLY (arg),
3030 TREE_THIS_VOLATILE (arg));
3031
3032 if (!c_mark_addressable (arg))
3033 return error_mark_node;
3034
3035 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
3036 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
3037
3038 argtype = build_pointer_type (argtype);
3039
3040 /* ??? Cope with user tricks that amount to offsetof. Delete this
3041 when we have proper support for integer constant expressions. */
3042 val = get_base_address (arg);
3043 if (val && TREE_CODE (val) == INDIRECT_REF
3044 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
3045 {
3046 tree op0 = fold_convert (argtype, fold_offsetof (arg, val)), op1;
3047
3048 op1 = fold_convert (argtype, TREE_OPERAND (val, 0));
3049 return fold_build2 (PLUS_EXPR, argtype, op0, op1);
3050 }
3051
3052 val = build1 (ADDR_EXPR, argtype, arg);
3053
3054 return val;
3055
3056 default:
3057 gcc_unreachable ();
3058 }
3059
3060 if (argtype == 0)
3061 argtype = TREE_TYPE (arg);
3062 return require_constant_value ? fold_build1_initializer (code, argtype, arg)
3063 : fold_build1 (code, argtype, arg);
3064}
3065
3066/* Return nonzero if REF is an lvalue valid for this language.
3067 Lvalues can be assigned, unless their type has TYPE_READONLY.
3068 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
3069
3070static int
3071lvalue_p (tree ref)
3072{
3073 enum tree_code code = TREE_CODE (ref);
3074
3075 switch (code)
3076 {
3077 case REALPART_EXPR:
3078 case IMAGPART_EXPR:
3079 case COMPONENT_REF:
3080 return lvalue_p (TREE_OPERAND (ref, 0));
3081
3082 case COMPOUND_LITERAL_EXPR:
3083 case STRING_CST:
3084 return 1;
3085
3086 case INDIRECT_REF:
3087 case ARRAY_REF:
3088 case VAR_DECL:
3089 case PARM_DECL:
3090 case RESULT_DECL:
3091 case ERROR_MARK:
3092 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3093 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3094
3095 case BIND_EXPR:
3096 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3097
3098 default:
3099 return 0;
3100 }
3101}
3102
3103/* Give an error for storing in something that is 'const'. */
3104
3105static void
3106readonly_error (tree arg, enum lvalue_use use)
3107{
3108 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement
3109 || use == lv_asm);
3110 /* Using this macro rather than (for example) arrays of messages
3111 ensures that all the format strings are checked at compile
3112 time. */
3113#define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \
3114 : (use == lv_increment ? (I) \
3115 : (use == lv_decrement ? (D) : (AS))))
3116 if (TREE_CODE (arg) == COMPONENT_REF)
3117 {
3118 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3119 readonly_error (TREE_OPERAND (arg, 0), use);
3120 else
3121 error (READONLY_MSG (G_("assignment of read-only member %qD"),
3122 G_("increment of read-only member %qD"),
3123 G_("decrement of read-only member %qD"),
3124 G_("read-only member %qD used as %<asm%> output")),
3125 TREE_OPERAND (arg, 1));
3126 }
3127 else if (TREE_CODE (arg) == VAR_DECL)
3128 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
3129 G_("increment of read-only variable %qD"),
3130 G_("decrement of read-only variable %qD"),
3131 G_("read-only variable %qD used as %<asm%> output")),
3132 arg);
3133 else
3134 error (READONLY_MSG (G_("assignment of read-only location"),
3135 G_("increment of read-only location"),
3136 G_("decrement of read-only location"),
3137 G_("read-only location used as %<asm%> output")));
3138}
3139
3140
3141/* Return nonzero if REF is an lvalue valid for this language;
3142 otherwise, print an error message and return zero. USE says
3143 how the lvalue is being used and so selects the error message. */
3144
3145static int
3146lvalue_or_else (tree ref, enum lvalue_use use)
3147{
3148 int win = lvalue_p (ref);
3149
3150 if (!win)
3151 lvalue_error (use);
3152
3153 return win;
3154}
3155
3156/* Mark EXP saying that we need to be able to take the
3157 address of it; it should not be allocated in a register.
3158 Returns true if successful. */
3159
3160bool
3161c_mark_addressable (tree exp)
3162{
3163 tree x = exp;
3164
3165 while (1)
3166 switch (TREE_CODE (x))
3167 {
3168 case COMPONENT_REF:
3169 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3170 {
3171 error
3172 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
3173 return false;
3174 }
3175
3176 /* ... fall through ... */
3177
3178 case ADDR_EXPR:
3179 case ARRAY_REF:
3180 case REALPART_EXPR:
3181 case IMAGPART_EXPR:
3182 x = TREE_OPERAND (x, 0);
3183 break;
3184
3185 case COMPOUND_LITERAL_EXPR:
3186 case CONSTRUCTOR:
3187 TREE_ADDRESSABLE (x) = 1;
3188 return true;
3189
3190 case VAR_DECL:
3191 case CONST_DECL:
3192 case PARM_DECL:
3193 case RESULT_DECL:
3194 if (C_DECL_REGISTER (x)
3195 && DECL_NONLOCAL (x))
3196 {
3197 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3198 {
3199 error
3200 ("global register variable %qD used in nested function", x);
3201 return false;
3202 }
3203 pedwarn ("register variable %qD used in nested function", x);
3204 }
3205 else if (C_DECL_REGISTER (x))
3206 {
3207 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3208 error ("address of global register variable %qD requested", x);
3209 else
3210 error ("address of register variable %qD requested", x);
3211 return false;
3212 }
3213
3214 /* drops in */
3215 case FUNCTION_DECL:
3216 TREE_ADDRESSABLE (x) = 1;
3217 /* drops out */
3218 default:
3219 return true;
3220 }
3221}
3222
3223/* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3224
3225tree
3226build_conditional_expr (tree ifexp, tree op1, tree op2)
3227{
3228 tree type1;
3229 tree type2;
3230 enum tree_code code1;
3231 enum tree_code code2;
3232 tree result_type = NULL;
3233 tree orig_op1 = op1, orig_op2 = op2;
3234
3235 /* Promote both alternatives. */
3236
3237 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3238 op1 = default_conversion (op1);
3239 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3240 op2 = default_conversion (op2);
3241
3242 if (TREE_CODE (ifexp) == ERROR_MARK
3243 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3244 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3245 return error_mark_node;
3246
3247 type1 = TREE_TYPE (op1);
3248 code1 = TREE_CODE (type1);
3249 type2 = TREE_TYPE (op2);
3250 code2 = TREE_CODE (type2);
3251
3252 /* C90 does not permit non-lvalue arrays in conditional expressions.
3253 In C99 they will be pointers by now. */
3254 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
3255 {
3256 error ("non-lvalue array in conditional expression");
3257 return error_mark_node;
3258 }
3259
3260 /* Quickly detect the usual case where op1 and op2 have the same type
3261 after promotion. */
3262 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3263 {
3264 if (type1 == type2)
3265 result_type = type1;
3266 else
3267 result_type = TYPE_MAIN_VARIANT (type1);
3268 }
3269 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3270 || code1 == COMPLEX_TYPE)
3271 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3272 || code2 == COMPLEX_TYPE))
3273 {
3274 result_type = c_common_type (type1, type2);
3275
3276 /* If -Wsign-compare, warn here if type1 and type2 have
3277 different signedness. We'll promote the signed to unsigned
3278 and later code won't know it used to be different.
3279 Do this check on the original types, so that explicit casts
3280 will be considered, but default promotions won't. */
3281 if (warn_sign_compare && !skip_evaluation)
3282 {
3283 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3284 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3285
3286 if (unsigned_op1 ^ unsigned_op2)
3287 {
3288 bool ovf;
3289
3290 /* Do not warn if the result type is signed, since the
3291 signed type will only be chosen if it can represent
3292 all the values of the unsigned type. */
3293 if (!TYPE_UNSIGNED (result_type))
3294 /* OK */;
3295 /* Do not warn if the signed quantity is an unsuffixed
3296 integer literal (or some static constant expression
3297 involving such literals) and it is non-negative. */
3298 else if ((unsigned_op2
3299 && tree_expr_nonnegative_warnv_p (op1, &ovf))
3300 || (unsigned_op1
3301 && tree_expr_nonnegative_warnv_p (op2, &ovf)))
3302 /* OK */;
3303 else
3304 warning (0, "signed and unsigned type in conditional expression");
3305 }
3306 }
3307 }
3308 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3309 {
3310 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3311 pedwarn ("ISO C forbids conditional expr with only one void side");
3312 result_type = void_type_node;
3313 }
3314 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3315 {
3316 if (comp_target_types (type1, type2))
3317 result_type = common_pointer_type (type1, type2);
3318 else if (null_pointer_constant_p (orig_op1))
3319 result_type = qualify_type (type2, type1);
3320 else if (null_pointer_constant_p (orig_op2))
3321 result_type = qualify_type (type1, type2);
3322 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3323 {
3324 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3325 pedwarn ("ISO C forbids conditional expr between "
3326 "%<void *%> and function pointer");
3327 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
3328 TREE_TYPE (type2)));
3329 }
3330 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3331 {
3332 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3333 pedwarn ("ISO C forbids conditional expr between "
3334 "%<void *%> and function pointer");
3335 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3336 TREE_TYPE (type1)));
3337 }
3338 else
3339 {
3340 pedwarn ("pointer type mismatch in conditional expression");
3341 result_type = build_pointer_type (void_type_node);
3342 }
3343 }
3344 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3345 {
3346 if (!null_pointer_constant_p (orig_op2))
3347 pedwarn ("pointer/integer type mismatch in conditional expression");
3348 else
3349 {
3350 op2 = null_pointer_node;
3351 }
3352 result_type = type1;
3353 }
3354 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3355 {
3356 if (!null_pointer_constant_p (orig_op1))
3357 pedwarn ("pointer/integer type mismatch in conditional expression");
3358 else
3359 {
3360 op1 = null_pointer_node;
3361 }
3362 result_type = type2;
3363 }
3364
3365 if (!result_type)
3366 {
3367 if (flag_cond_mismatch)
3368 result_type = void_type_node;
3369 else
3370 {
3371 error ("type mismatch in conditional expression");
3372 return error_mark_node;
3373 }
3374 }
3375
3376 /* Merge const and volatile flags of the incoming types. */
3377 result_type
3378 = build_type_variant (result_type,
3379 TREE_READONLY (op1) || TREE_READONLY (op2),
3380 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3381
3382 if (result_type != TREE_TYPE (op1))
3383 op1 = convert_and_check (result_type, op1);
3384 if (result_type != TREE_TYPE (op2))
3385 op2 = convert_and_check (result_type, op2);
3386
3387 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3388}
3389
3390/* Return a compound expression that performs two expressions and
3391 returns the value of the second of them. */
3392
3393tree
3394build_compound_expr (tree expr1, tree expr2)
3395{
3396 if (!TREE_SIDE_EFFECTS (expr1))
3397 {
3398 /* The left-hand operand of a comma expression is like an expression
3399 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3400 any side-effects, unless it was explicitly cast to (void). */
3401 if (warn_unused_value)
3402 {
3403 if (VOID_TYPE_P (TREE_TYPE (expr1))
3404 && (TREE_CODE (expr1) == NOP_EXPR
3405 || TREE_CODE (expr1) == CONVERT_EXPR))
3406 ; /* (void) a, b */
3407 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3408 && TREE_CODE (expr1) == COMPOUND_EXPR
3409 && (TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR
3410 || TREE_CODE (TREE_OPERAND (expr1, 1)) == NOP_EXPR))
3411 ; /* (void) a, (void) b, c */
3412 else
3413 warning (0, "left-hand operand of comma expression has no effect");
3414 }
3415 }
3416
3417 /* With -Wunused, we should also warn if the left-hand operand does have
3418 side-effects, but computes a value which is not used. For example, in
3419 `foo() + bar(), baz()' the result of the `+' operator is not used,
3420 so we should issue a warning. */
3421 else if (warn_unused_value)
3422 warn_if_unused_value (expr1, input_location);
3423
3424 if (expr2 == error_mark_node)
3425 return error_mark_node;
3426
3427 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3428}
3429
3430/* Build an expression representing a cast to type TYPE of expression EXPR. */
3431
3432tree
3433build_c_cast (tree type, tree expr)
3434{
3435 tree value = expr;
3436
3437 if (type == error_mark_node || expr == error_mark_node)
3438 return error_mark_node;
3439
3440 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3441 only in <protocol> qualifications. But when constructing cast expressions,
3442 the protocols do matter and must be kept around. */
3443 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3444 return build1 (NOP_EXPR, type, expr);
3445
3446 type = TYPE_MAIN_VARIANT (type);
3447
3448 if (TREE_CODE (type) == ARRAY_TYPE)
3449 {
3450 error ("cast specifies array type");
3451 return error_mark_node;
3452 }
3453
3454 if (TREE_CODE (type) == FUNCTION_TYPE)
3455 {
3456 error ("cast specifies function type");
3457 return error_mark_node;
3458 }
3459
3460 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3461 {
3462 if (pedantic)
3463 {
3464 if (TREE_CODE (type) == RECORD_TYPE
3465 || TREE_CODE (type) == UNION_TYPE)
3466 pedwarn ("ISO C forbids casting nonscalar to the same type");
3467 }
3468 }
3469 else if (TREE_CODE (type) == UNION_TYPE)
3470 {
3471 tree field;
3472
3473 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3474 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3475 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3476 break;
3477
3478 if (field)
3479 {
3480 tree t;
3481
3482 if (pedantic)
3483 pedwarn ("ISO C forbids casts to union type");
3484 t = digest_init (type,
3485 build_constructor_single (type, field, value),
3486 true, 0);
3487 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3488 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3489 return t;
3490 }
3491 error ("cast to union type from type not present in union");
3492 return error_mark_node;
3493 }
3494 else
3495 {
3496 tree otype, ovalue;
3497
3498 if (type == void_type_node)
3499 return build1 (CONVERT_EXPR, type, value);
3500
3501 otype = TREE_TYPE (value);
3502
3503 /* Optionally warn about potentially worrisome casts. */
3504
3505 if (warn_cast_qual
3506 && TREE_CODE (type) == POINTER_TYPE
3507 && TREE_CODE (otype) == POINTER_TYPE)
3508 {
3509 tree in_type = type;
3510 tree in_otype = otype;
3511 int added = 0;
3512 int discarded = 0;
3513
3514 /* Check that the qualifiers on IN_TYPE are a superset of
3515 the qualifiers of IN_OTYPE. The outermost level of
3516 POINTER_TYPE nodes is uninteresting and we stop as soon
3517 as we hit a non-POINTER_TYPE node on either type. */
3518 do
3519 {
3520 in_otype = TREE_TYPE (in_otype);
3521 in_type = TREE_TYPE (in_type);
3522
3523 /* GNU C allows cv-qualified function types. 'const'
3524 means the function is very pure, 'volatile' means it
3525 can't return. We need to warn when such qualifiers
3526 are added, not when they're taken away. */
3527 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3528 && TREE_CODE (in_type) == FUNCTION_TYPE)
3529 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3530 else
3531 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3532 }
3533 while (TREE_CODE (in_type) == POINTER_TYPE
3534 && TREE_CODE (in_otype) == POINTER_TYPE);
3535
3536 if (added)
3537 warning (0, "cast adds new qualifiers to function type");
3538
3539 if (discarded)
3540 /* There are qualifiers present in IN_OTYPE that are not
3541 present in IN_TYPE. */
3542 warning (0, "cast discards qualifiers from pointer target type");
3543 }
3544
3545 /* Warn about possible alignment problems. */
3546 if (STRICT_ALIGNMENT
3547 && TREE_CODE (type) == POINTER_TYPE
3548 && TREE_CODE (otype) == POINTER_TYPE
3549 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3550 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3551 /* Don't warn about opaque types, where the actual alignment
3552 restriction is unknown. */
3553 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3554 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3555 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3556 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3557 warning (OPT_Wcast_align,
3558 "cast increases required alignment of target type");
3559
3560 if (TREE_CODE (type) == INTEGER_TYPE
3561 && TREE_CODE (otype) == POINTER_TYPE
3562 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
3563 /* Unlike conversion of integers to pointers, where the
3564 warning is disabled for converting constants because
3565 of cases such as SIG_*, warn about converting constant
3566 pointers to integers. In some cases it may cause unwanted
3567 sign extension, and a warning is appropriate. */
3568 warning (OPT_Wpointer_to_int_cast,
3569 "cast from pointer to integer of different size");
3570
3571 if (TREE_CODE (value) == CALL_EXPR
3572 && TREE_CODE (type) != TREE_CODE (otype))
3573 warning (OPT_Wbad_function_cast, "cast from function call of type %qT "
3574 "to non-matching type %qT", otype, type);
3575
3576 if (TREE_CODE (type) == POINTER_TYPE
3577 && TREE_CODE (otype) == INTEGER_TYPE
3578 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3579 /* Don't warn about converting any constant. */
3580 && !TREE_CONSTANT (value))
3581 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer "
3582 "of different size");
3583
3584 if (warn_strict_aliasing <= 2)
3585 strict_aliasing_warning (otype, type, expr);
3586
3587 /* If pedantic, warn for conversions between function and object
3588 pointer types, except for converting a null pointer constant
3589 to function pointer type. */
3590 if (pedantic
3591 && TREE_CODE (type) == POINTER_TYPE
3592 && TREE_CODE (otype) == POINTER_TYPE
3593 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3594 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3595 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3596
3597 if (pedantic
3598 && TREE_CODE (type) == POINTER_TYPE
3599 && TREE_CODE (otype) == POINTER_TYPE
3600 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3601 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3602 && !null_pointer_constant_p (value))
3603 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3604
3605 ovalue = value;
3606 value = convert (type, value);
3607
3608 /* Ignore any integer overflow caused by the cast. */
3609 if (TREE_CODE (value) == INTEGER_CST)
3610 {
3611 if (CONSTANT_CLASS_P (ovalue)
3612 && (TREE_OVERFLOW (ovalue) || TREE_CONSTANT_OVERFLOW (ovalue)))
3613 {
3614 /* Avoid clobbering a shared constant. */
3615 value = copy_node (value);
3616 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3617 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3618 }
3619 else if (TREE_OVERFLOW (value) || TREE_CONSTANT_OVERFLOW (value))
3620 /* Reset VALUE's overflow flags, ensuring constant sharing. */
3621 value = build_int_cst_wide (TREE_TYPE (value),
3622 TREE_INT_CST_LOW (value),
3623 TREE_INT_CST_HIGH (value));
3624 }
3625 }
3626
3627 /* Don't let a cast be an lvalue. */
3628 if (value == expr)
3629 value = non_lvalue (value);
3630
3631 return value;
3632}
3633
3634/* Interpret a cast of expression EXPR to type TYPE. */
3635tree
3636c_cast_expr (struct c_type_name *type_name, tree expr)
3637{
3638 tree type;
3639 int saved_wsp = warn_strict_prototypes;
3640
3641 /* This avoids warnings about unprototyped casts on
3642 integers. E.g. "#define SIG_DFL (void(*)())0". */
3643 if (TREE_CODE (expr) == INTEGER_CST)
3644 warn_strict_prototypes = 0;
3645 type = groktypename (type_name);
3646 warn_strict_prototypes = saved_wsp;
3647
3648 return build_c_cast (type, expr);
3649}
3650
3651/* Build an assignment expression of lvalue LHS from value RHS.
3652 MODIFYCODE is the code for a binary operator that we use
3653 to combine the old value of LHS with RHS to get the new value.
3654 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3655
3656tree
3657build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3658{
3659 tree result;
3660 tree newrhs;
3661 tree lhstype = TREE_TYPE (lhs);
3662 tree olhstype = lhstype;
3663
3664 /* Types that aren't fully specified cannot be used in assignments. */
3665 lhs = require_complete_type (lhs);
3666
3667 /* Avoid duplicate error messages from operands that had errors. */
3668 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3669 return error_mark_node;
3670
3671 if (!lvalue_or_else (lhs, lv_assign))
3672 return error_mark_node;
3673
3674 STRIP_TYPE_NOPS (rhs);
3675
3676 newrhs = rhs;
3677
3678 /* If a binary op has been requested, combine the old LHS value with the RHS
3679 producing the value we should actually store into the LHS. */
3680
3681 if (modifycode != NOP_EXPR)
3682 {
3683 lhs = stabilize_reference (lhs);
3684 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3685 }
3686
3687 /* Give an error for storing in something that is 'const'. */
3688
3689 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3690 || ((TREE_CODE (lhstype) == RECORD_TYPE
3691 || TREE_CODE (lhstype) == UNION_TYPE)
3692 && C_TYPE_FIELDS_READONLY (lhstype)))
3693 {
3694 readonly_error (lhs, lv_assign);
3695 return error_mark_node;
3696 }
3697
3698 /* If storing into a structure or union member,
3699 it has probably been given type `int'.
3700 Compute the type that would go with
3701 the actual amount of storage the member occupies. */
3702
3703 if (TREE_CODE (lhs) == COMPONENT_REF
3704 && (TREE_CODE (lhstype) == INTEGER_TYPE
3705 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3706 || TREE_CODE (lhstype) == REAL_TYPE
3707 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3708 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3709
3710 /* If storing in a field that is in actuality a short or narrower than one,
3711 we must store in the field in its actual type. */
3712
3713 if (lhstype != TREE_TYPE (lhs))
3714 {
3715 lhs = copy_node (lhs);
3716 TREE_TYPE (lhs) = lhstype;
3717 }
3718
3719 /* Convert new value to destination type. */
3720
3721 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3722 NULL_TREE, NULL_TREE, 0);
3723 if (TREE_CODE (newrhs) == ERROR_MARK)
3724 return error_mark_node;
3725
3726 /* Emit ObjC write barrier, if necessary. */
3727 if (c_dialect_objc () && flag_objc_gc)
3728 {
3729 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3730 if (result)
3731 return result;
3732 }
3733
3734 /* Scan operands. */
3735
3736 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3737 TREE_SIDE_EFFECTS (result) = 1;
3738
3739 /* If we got the LHS in a different type for storing in,
3740 convert the result back to the nominal type of LHS
3741 so that the value we return always has the same type
3742 as the LHS argument. */
3743
3744 if (olhstype == TREE_TYPE (result))
3745 return result;
3746 return convert_for_assignment (olhstype, result, ic_assign,
3747 NULL_TREE, NULL_TREE, 0);
3748}
3749
3750/* Convert value RHS to type TYPE as preparation for an assignment
3751 to an lvalue of type TYPE.
3752 The real work of conversion is done by `convert'.
3753 The purpose of this function is to generate error messages
3754 for assignments that are not allowed in C.
3755 ERRTYPE says whether it is argument passing, assignment,
3756 initialization or return.
3757
3758 FUNCTION is a tree for the function being called.
3759 PARMNUM is the number of the argument, for printing in error messages. */
3760
3761static tree
3762convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3763 tree fundecl, tree function, int parmnum)
3764{
3765 enum tree_code codel = TREE_CODE (type);
3766 tree rhstype;
3767 enum tree_code coder;
3768 tree rname = NULL_TREE;
3769 bool objc_ok = false;
3770
3771 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3772 {
3773 tree selector;
3774 /* Change pointer to function to the function itself for
3775 diagnostics. */
3776 if (TREE_CODE (function) == ADDR_EXPR
3777 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3778 function = TREE_OPERAND (function, 0);
3779
3780 /* Handle an ObjC selector specially for diagnostics. */
3781 selector = objc_message_selector ();
3782 rname = function;
3783 if (selector && parmnum > 2)
3784 {
3785 rname = selector;
3786 parmnum -= 2;
3787 }
3788 }
3789
3790 /* This macro is used to emit diagnostics to ensure that all format
3791 strings are complete sentences, visible to gettext and checked at
3792 compile time. */
3793#define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3794 do { \
3795 switch (errtype) \
3796 { \
3797 case ic_argpass: \
3798 pedwarn (AR, parmnum, rname); \
3799 break; \
3800 case ic_argpass_nonproto: \
3801 warning (0, AR, parmnum, rname); \
3802 break; \
3803 case ic_assign: \
3804 pedwarn (AS); \
3805 break; \
3806 case ic_init: \
3807 pedwarn (IN); \
3808 break; \
3809 case ic_return: \
3810 pedwarn (RE); \
3811 break; \
3812 default: \
3813 gcc_unreachable (); \
3814 } \
3815 } while (0)
3816
3817 STRIP_TYPE_NOPS (rhs);
3818
3819 if (optimize && TREE_CODE (rhs) == VAR_DECL
3820 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE)
3821 rhs = decl_constant_value_for_broken_optimization (rhs);
3822
3823 rhstype = TREE_TYPE (rhs);
3824 coder = TREE_CODE (rhstype);
3825
3826 if (coder == ERROR_MARK)
3827 return error_mark_node;
3828
3829 if (c_dialect_objc ())
3830 {
3831 int parmno;
3832
3833 switch (errtype)
3834 {
3835 case ic_return:
3836 parmno = 0;
3837 break;
3838
3839 case ic_assign:
3840 parmno = -1;
3841 break;
3842
3843 case ic_init:
3844 parmno = -2;
3845 break;
3846
3847 default:
3848 parmno = parmnum;
3849 break;
3850 }
3851
3852 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
3853 }
3854
3855 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3856 return rhs;
3857
3858 if (coder == VOID_TYPE)
3859 {
3860 /* Except for passing an argument to an unprototyped function,
3861 this is a constraint violation. When passing an argument to
3862 an unprototyped function, it is compile-time undefined;
3863 making it a constraint in that case was rejected in
3864 DR#252. */
3865 error ("void value not ignored as it ought to be");
3866 return error_mark_node;
3867 }
3868 /* A type converts to a reference to it.
3869 This code doesn't fully support references, it's just for the
3870 special case of va_start and va_copy. */
3871 if (codel == REFERENCE_TYPE
3872 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3873 {
3874 if (!lvalue_p (rhs))
3875 {
3876 error ("cannot pass rvalue to reference parameter");
3877 return error_mark_node;
3878 }
3879 if (!c_mark_addressable (rhs))
3880 return error_mark_node;
3881 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3882
3883 /* We already know that these two types are compatible, but they
3884 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3885 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3886 likely to be va_list, a typedef to __builtin_va_list, which
3887 is different enough that it will cause problems later. */
3888 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3889 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3890
3891 rhs = build1 (NOP_EXPR, type, rhs);
3892 return rhs;
3893 }
3894 /* Some types can interconvert without explicit casts. */
3895 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
|
3896 && vector_types_convertible_p (type, TREE_TYPE (rhs)))
| 3896 && vector_types_convertible_p (type, TREE_TYPE (rhs), true))
|
3897 return convert (type, rhs);
3898 /* Arithmetic types all interconvert, and enum is treated like int. */
3899 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3900 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3901 || codel == BOOLEAN_TYPE)
3902 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3903 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3904 || coder == BOOLEAN_TYPE))
3905 return convert_and_check (type, rhs);
3906
3907 /* Aggregates in different TUs might need conversion. */
3908 if ((codel == RECORD_TYPE || codel == UNION_TYPE)
3909 && codel == coder
3910 && comptypes (type, rhstype))
3911 return convert_and_check (type, rhs);
3912
3913 /* Conversion to a transparent union from its member types.
3914 This applies only to function arguments. */
3915 if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3916 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3917 {
3918 tree memb, marginal_memb = NULL_TREE;
3919
3920 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb))
3921 {
3922 tree memb_type = TREE_TYPE (memb);
3923
3924 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3925 TYPE_MAIN_VARIANT (rhstype)))
3926 break;
3927
3928 if (TREE_CODE (memb_type) != POINTER_TYPE)
3929 continue;
3930
3931 if (coder == POINTER_TYPE)
3932 {
3933 tree ttl = TREE_TYPE (memb_type);
3934 tree ttr = TREE_TYPE (rhstype);
3935
3936 /* Any non-function converts to a [const][volatile] void *
3937 and vice versa; otherwise, targets must be the same.
3938 Meanwhile, the lhs target must have all the qualifiers of
3939 the rhs. */
3940 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3941 || comp_target_types (memb_type, rhstype))
3942 {
3943 /* If this type won't generate any warnings, use it. */
3944 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3945 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3946 && TREE_CODE (ttl) == FUNCTION_TYPE)
3947 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3948 == TYPE_QUALS (ttr))
3949 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3950 == TYPE_QUALS (ttl))))
3951 break;
3952
3953 /* Keep looking for a better type, but remember this one. */
3954 if (!marginal_memb)
3955 marginal_memb = memb;
3956 }
3957 }
3958
3959 /* Can convert integer zero to any pointer type. */
3960 if (null_pointer_constant_p (rhs))
3961 {
3962 rhs = null_pointer_node;
3963 break;
3964 }
3965 }
3966
3967 if (memb || marginal_memb)
3968 {
3969 if (!memb)
3970 {
3971 /* We have only a marginally acceptable member type;
3972 it needs a warning. */
3973 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb));
3974 tree ttr = TREE_TYPE (rhstype);
3975
3976 /* Const and volatile mean something different for function
3977 types, so the usual warnings are not appropriate. */
3978 if (TREE_CODE (ttr) == FUNCTION_TYPE
3979 && TREE_CODE (ttl) == FUNCTION_TYPE)
3980 {
3981 /* Because const and volatile on functions are
3982 restrictions that say the function will not do
3983 certain things, it is okay to use a const or volatile
3984 function where an ordinary one is wanted, but not
3985 vice-versa. */
3986 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3987 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE "
3988 "makes qualified function "
3989 "pointer from unqualified"),
3990 G_("assignment makes qualified "
3991 "function pointer from "
3992 "unqualified"),
3993 G_("initialization makes qualified "
3994 "function pointer from "
3995 "unqualified"),
3996 G_("return makes qualified function "
3997 "pointer from unqualified"));
3998 }
3999 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4000 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4001 "qualifiers from pointer target type"),
4002 G_("assignment discards qualifiers "
4003 "from pointer target type"),
4004 G_("initialization discards qualifiers "
4005 "from pointer target type"),
4006 G_("return discards qualifiers from "
4007 "pointer target type"));
4008
4009 memb = marginal_memb;
4010 }
4011
4012 if (pedantic && (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl)))
4013 pedwarn ("ISO C prohibits argument conversion to union type");
4014
4015 return build_constructor_single (type, memb, rhs);
4016 }
4017 }
4018
4019 /* Conversions among pointers */
4020 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4021 && (coder == codel))
4022 {
4023 tree ttl = TREE_TYPE (type);
4024 tree ttr = TREE_TYPE (rhstype);
4025 tree mvl = ttl;
4026 tree mvr = ttr;
4027 bool is_opaque_pointer;
4028 int target_cmp = 0; /* Cache comp_target_types () result. */
4029
4030 if (TREE_CODE (mvl) != ARRAY_TYPE)
4031 mvl = TYPE_MAIN_VARIANT (mvl);
4032 if (TREE_CODE (mvr) != ARRAY_TYPE)
4033 mvr = TYPE_MAIN_VARIANT (mvr);
4034 /* Opaque pointers are treated like void pointers. */
4035 is_opaque_pointer = (targetm.vector_opaque_p (type)
4036 || targetm.vector_opaque_p (rhstype))
4037 && TREE_CODE (ttl) == VECTOR_TYPE
4038 && TREE_CODE (ttr) == VECTOR_TYPE;
4039
4040 /* C++ does not allow the implicit conversion void* -> T*. However,
4041 for the purpose of reducing the number of false positives, we
4042 tolerate the special case of
4043
4044 int *p = NULL;
4045
4046 where NULL is typically defined in C to be '(void *) 0'. */
4047 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
4048 warning (OPT_Wc___compat, "request for implicit conversion from "
4049 "%qT to %qT not permitted in C++", rhstype, type);
4050
4051 /* Check if the right-hand side has a format attribute but the
4052 left-hand side doesn't. */
4053 if (warn_missing_format_attribute
4054 && check_missing_format_attribute (type, rhstype))
4055 {
4056 switch (errtype)
4057 {
4058 case ic_argpass:
4059 case ic_argpass_nonproto:
4060 warning (OPT_Wmissing_format_attribute,
4061 "argument %d of %qE might be "
4062 "a candidate for a format attribute",
4063 parmnum, rname);
4064 break;
4065 case ic_assign:
4066 warning (OPT_Wmissing_format_attribute,
4067 "assignment left-hand side might be "
4068 "a candidate for a format attribute");
4069 break;
4070 case ic_init:
4071 warning (OPT_Wmissing_format_attribute,
4072 "initialization left-hand side might be "
4073 "a candidate for a format attribute");
4074 break;
4075 case ic_return:
4076 warning (OPT_Wmissing_format_attribute,
4077 "return type might be "
4078 "a candidate for a format attribute");
4079 break;
4080 default:
4081 gcc_unreachable ();
4082 }
4083 }
4084
4085 /* Any non-function converts to a [const][volatile] void *
4086 and vice versa; otherwise, targets must be the same.
4087 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4088 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4089 || (target_cmp = comp_target_types (type, rhstype))
4090 || is_opaque_pointer
4091 || (c_common_unsigned_type (mvl)
4092 == c_common_unsigned_type (mvr)))
4093 {
4094 if (pedantic
4095 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
4096 ||
4097 (VOID_TYPE_P (ttr)
4098 && !null_pointer_constant_p (rhs)
4099 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4100 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
4101 "%qE between function pointer "
4102 "and %<void *%>"),
4103 G_("ISO C forbids assignment between "
4104 "function pointer and %<void *%>"),
4105 G_("ISO C forbids initialization between "
4106 "function pointer and %<void *%>"),
4107 G_("ISO C forbids return between function "
4108 "pointer and %<void *%>"));
4109 /* Const and volatile mean something different for function types,
4110 so the usual warnings are not appropriate. */
4111 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4112 && TREE_CODE (ttl) != FUNCTION_TYPE)
4113 {
4114 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4115 {
4116 /* Types differing only by the presence of the 'volatile'
4117 qualifier are acceptable if the 'volatile' has been added
4118 in by the Objective-C EH machinery. */
4119 if (!objc_type_quals_match (ttl, ttr))
4120 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4121 "qualifiers from pointer target type"),
4122 G_("assignment discards qualifiers "
4123 "from pointer target type"),
4124 G_("initialization discards qualifiers "
4125 "from pointer target type"),
4126 G_("return discards qualifiers from "
4127 "pointer target type"));
4128 }
4129 /* If this is not a case of ignoring a mismatch in signedness,
4130 no warning. */
4131 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4132 || target_cmp)
4133 ;
4134 /* If there is a mismatch, do warn. */
4135 else if (warn_pointer_sign)
4136 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument "
4137 "%d of %qE differ in signedness"),
4138 G_("pointer targets in assignment "
4139 "differ in signedness"),
4140 G_("pointer targets in initialization "
4141 "differ in signedness"),
4142 G_("pointer targets in return differ "
4143 "in signedness"));
4144 }
4145 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4146 && TREE_CODE (ttr) == FUNCTION_TYPE)
4147 {
4148 /* Because const and volatile on functions are restrictions
4149 that say the function will not do certain things,
4150 it is okay to use a const or volatile function
4151 where an ordinary one is wanted, but not vice-versa. */
4152 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4153 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4154 "qualified function pointer "
4155 "from unqualified"),
4156 G_("assignment makes qualified function "
4157 "pointer from unqualified"),
4158 G_("initialization makes qualified "
4159 "function pointer from unqualified"),
4160 G_("return makes qualified function "
4161 "pointer from unqualified"));
4162 }
4163 }
4164 else
4165 /* Avoid warning about the volatile ObjC EH puts on decls. */
4166 if (!objc_ok)
4167 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from "
4168 "incompatible pointer type"),
4169 G_("assignment from incompatible pointer type"),
4170 G_("initialization from incompatible "
4171 "pointer type"),
4172 G_("return from incompatible pointer type"));
4173
4174 return convert (type, rhs);
4175 }
4176 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
4177 {
4178 /* ??? This should not be an error when inlining calls to
4179 unprototyped functions. */
4180 error ("invalid use of non-lvalue array");
4181 return error_mark_node;
4182 }
4183 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4184 {
4185 /* An explicit constant 0 can convert to a pointer,
4186 or one that results from arithmetic, even including
4187 a cast to integer type. */
4188 if (!null_pointer_constant_p (rhs))
4189 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4190 "pointer from integer without a cast"),
4191 G_("assignment makes pointer from integer "
4192 "without a cast"),
4193 G_("initialization makes pointer from "
4194 "integer without a cast"),
4195 G_("return makes pointer from integer "
4196 "without a cast"));
4197
4198 return convert (type, rhs);
4199 }
4200 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4201 {
4202 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer "
4203 "from pointer without a cast"),
4204 G_("assignment makes integer from pointer "
4205 "without a cast"),
4206 G_("initialization makes integer from pointer "
4207 "without a cast"),
4208 G_("return makes integer from pointer "
4209 "without a cast"));
4210 return convert (type, rhs);
4211 }
4212 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
4213 return convert (type, rhs);
4214
4215 switch (errtype)
4216 {
4217 case ic_argpass:
4218 case ic_argpass_nonproto:
4219 /* ??? This should not be an error when inlining calls to
4220 unprototyped functions. */
4221 error ("incompatible type for argument %d of %qE", parmnum, rname);
4222 break;
4223 case ic_assign:
4224 error ("incompatible types in assignment");
4225 break;
4226 case ic_init:
4227 error ("incompatible types in initialization");
4228 break;
4229 case ic_return:
4230 error ("incompatible types in return");
4231 break;
4232 default:
4233 gcc_unreachable ();
4234 }
4235
4236 return error_mark_node;
4237}
4238
4239/* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
4240 is used for error and warning reporting and indicates which argument
4241 is being processed. */
4242
4243tree
4244c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
4245{
4246 tree ret, type;
4247
4248 /* If FN was prototyped at the call site, the value has been converted
4249 already in convert_arguments.
4250 However, we might see a prototype now that was not in place when
4251 the function call was seen, so check that the VALUE actually matches
4252 PARM before taking an early exit. */
4253 if (!value
4254 || (TYPE_ARG_TYPES (TREE_TYPE (fn))
4255 && (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
4256 == TYPE_MAIN_VARIANT (TREE_TYPE (value)))))
4257 return value;
4258
4259 type = TREE_TYPE (parm);
4260 ret = convert_for_assignment (type, value,
4261 ic_argpass_nonproto, fn,
4262 fn, argnum);
4263 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
4264 && INTEGRAL_TYPE_P (type)
4265 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
4266 ret = default_conversion (ret);
4267 return ret;
4268}
4269
4270/* If VALUE is a compound expr all of whose expressions are constant, then
4271 return its value. Otherwise, return error_mark_node.
4272
4273 This is for handling COMPOUND_EXPRs as initializer elements
4274 which is allowed with a warning when -pedantic is specified. */
4275
4276static tree
4277valid_compound_expr_initializer (tree value, tree endtype)
4278{
4279 if (TREE_CODE (value) == COMPOUND_EXPR)
4280 {
4281 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4282 == error_mark_node)
4283 return error_mark_node;
4284 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4285 endtype);
4286 }
4287 else if (!initializer_constant_valid_p (value, endtype))
4288 return error_mark_node;
4289 else
4290 return value;
4291}
4292
4293/* Perform appropriate conversions on the initial value of a variable,
4294 store it in the declaration DECL,
4295 and print any error messages that are appropriate.
4296 If the init is invalid, store an ERROR_MARK. */
4297
4298void
4299store_init_value (tree decl, tree init)
4300{
4301 tree value, type;
4302
4303 /* If variable's type was invalidly declared, just ignore it. */
4304
4305 type = TREE_TYPE (decl);
4306 if (TREE_CODE (type) == ERROR_MARK)
4307 return;
4308
4309 /* Digest the specified initializer into an expression. */
4310
4311 value = digest_init (type, init, true, TREE_STATIC (decl));
4312
4313 /* Store the expression if valid; else report error. */
4314
4315 if (!in_system_header
4316 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4317 warning (OPT_Wtraditional, "traditional C rejects automatic "
4318 "aggregate initialization");
4319
4320 DECL_INITIAL (decl) = value;
4321
4322 /* ANSI wants warnings about out-of-range constant initializers. */
4323 STRIP_TYPE_NOPS (value);
4324 constant_expression_warning (value);
4325
4326 /* Check if we need to set array size from compound literal size. */
4327 if (TREE_CODE (type) == ARRAY_TYPE
4328 && TYPE_DOMAIN (type) == 0
4329 && value != error_mark_node)
4330 {
4331 tree inside_init = init;
4332
4333 STRIP_TYPE_NOPS (inside_init);
4334 inside_init = fold (inside_init);
4335
4336 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4337 {
4338 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4339
4340 if (TYPE_DOMAIN (TREE_TYPE (cldecl)))
4341 {
4342 /* For int foo[] = (int [3]){1}; we need to set array size
4343 now since later on array initializer will be just the
4344 brace enclosed list of the compound literal. */
4345 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4346 TREE_TYPE (decl) = type;
4347 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl));
4348 layout_type (type);
4349 layout_decl (cldecl, 0);
4350 }
4351 }
4352 }
4353}
4354
4355/* Methods for storing and printing names for error messages. */
4356
4357/* Implement a spelling stack that allows components of a name to be pushed
4358 and popped. Each element on the stack is this structure. */
4359
4360struct spelling
4361{
4362 int kind;
4363 union
4364 {
4365 unsigned HOST_WIDE_INT i;
4366 const char *s;
4367 } u;
4368};
4369
4370#define SPELLING_STRING 1
4371#define SPELLING_MEMBER 2
4372#define SPELLING_BOUNDS 3
4373
4374static struct spelling *spelling; /* Next stack element (unused). */
4375static struct spelling *spelling_base; /* Spelling stack base. */
4376static int spelling_size; /* Size of the spelling stack. */
4377
4378/* Macros to save and restore the spelling stack around push_... functions.
4379 Alternative to SAVE_SPELLING_STACK. */
4380
4381#define SPELLING_DEPTH() (spelling - spelling_base)
4382#define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4383
4384/* Push an element on the spelling stack with type KIND and assign VALUE
4385 to MEMBER. */
4386
4387#define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4388{ \
4389 int depth = SPELLING_DEPTH (); \
4390 \
4391 if (depth >= spelling_size) \
4392 { \
4393 spelling_size += 10; \
4394 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4395 spelling_size); \
4396 RESTORE_SPELLING_DEPTH (depth); \
4397 } \
4398 \
4399 spelling->kind = (KIND); \
4400 spelling->MEMBER = (VALUE); \
4401 spelling++; \
4402}
4403
4404/* Push STRING on the stack. Printed literally. */
4405
4406static void
4407push_string (const char *string)
4408{
4409 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4410}
4411
4412/* Push a member name on the stack. Printed as '.' STRING. */
4413
4414static void
4415push_member_name (tree decl)
4416{
4417 const char *const string
4418 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4419 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4420}
4421
4422/* Push an array bounds on the stack. Printed as [BOUNDS]. */
4423
4424static void
4425push_array_bounds (unsigned HOST_WIDE_INT bounds)
4426{
4427 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4428}
4429
4430/* Compute the maximum size in bytes of the printed spelling. */
4431
4432static int
4433spelling_length (void)
4434{
4435 int size = 0;
4436 struct spelling *p;
4437
4438 for (p = spelling_base; p < spelling; p++)
4439 {
4440 if (p->kind == SPELLING_BOUNDS)
4441 size += 25;
4442 else
4443 size += strlen (p->u.s) + 1;
4444 }
4445
4446 return size;
4447}
4448
4449/* Print the spelling to BUFFER and return it. */
4450
4451static char *
4452print_spelling (char *buffer)
4453{
4454 char *d = buffer;
4455 struct spelling *p;
4456
4457 for (p = spelling_base; p < spelling; p++)
4458 if (p->kind == SPELLING_BOUNDS)
4459 {
4460 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i);
4461 d += strlen (d);
4462 }
4463 else
4464 {
4465 const char *s;
4466 if (p->kind == SPELLING_MEMBER)
4467 *d++ = '.';
4468 for (s = p->u.s; (*d = *s++); d++)
4469 ;
4470 }
4471 *d++ = '\0';
4472 return buffer;
4473}
4474
4475/* Issue an error message for a bad initializer component.
4476 MSGID identifies the message.
4477 The component name is taken from the spelling stack. */
4478
4479void
4480error_init (const char *msgid)
4481{
4482 char *ofwhat;
4483
4484 error ("%s", _(msgid));
4485 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4486 if (*ofwhat)
4487 error ("(near initialization for %qs)", ofwhat);
4488}
4489
4490/* Issue a pedantic warning for a bad initializer component.
4491 MSGID identifies the message.
4492 The component name is taken from the spelling stack. */
4493
4494void
4495pedwarn_init (const char *msgid)
4496{
4497 char *ofwhat;
4498
4499 pedwarn ("%s", _(msgid));
4500 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4501 if (*ofwhat)
4502 pedwarn ("(near initialization for %qs)", ofwhat);
4503}
4504
4505/* Issue a warning for a bad initializer component.
4506 MSGID identifies the message.
4507 The component name is taken from the spelling stack. */
4508
4509static void
4510warning_init (const char *msgid)
4511{
4512 char *ofwhat;
4513
4514 warning (0, "%s", _(msgid));
4515 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4516 if (*ofwhat)
4517 warning (0, "(near initialization for %qs)", ofwhat);
4518}
4519
4520/* If TYPE is an array type and EXPR is a parenthesized string
4521 constant, warn if pedantic that EXPR is being used to initialize an
4522 object of type TYPE. */
4523
4524void
4525maybe_warn_string_init (tree type, struct c_expr expr)
4526{
4527 if (pedantic
4528 && TREE_CODE (type) == ARRAY_TYPE
4529 && TREE_CODE (expr.value) == STRING_CST
4530 && expr.original_code != STRING_CST)
4531 pedwarn_init ("array initialized from parenthesized string constant");
4532}
4533
4534/* Digest the parser output INIT as an initializer for type TYPE.
4535 Return a C expression of type TYPE to represent the initial value.
4536
4537 If INIT is a string constant, STRICT_STRING is true if it is
4538 unparenthesized or we should not warn here for it being parenthesized.
4539 For other types of INIT, STRICT_STRING is not used.
4540
4541 REQUIRE_CONSTANT requests an error if non-constant initializers or
4542 elements are seen. */
4543
4544static tree
4545digest_init (tree type, tree init, bool strict_string, int require_constant)
4546{
4547 enum tree_code code = TREE_CODE (type);
4548 tree inside_init = init;
4549
4550 if (type == error_mark_node
4551 || !init
4552 || init == error_mark_node
4553 || TREE_TYPE (init) == error_mark_node)
4554 return error_mark_node;
4555
4556 STRIP_TYPE_NOPS (inside_init);
4557
4558 inside_init = fold (inside_init);
4559
4560 /* Initialization of an array of chars from a string constant
4561 optionally enclosed in braces. */
4562
4563 if (code == ARRAY_TYPE && inside_init
4564 && TREE_CODE (inside_init) == STRING_CST)
4565 {
4566 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4567 /* Note that an array could be both an array of character type
4568 and an array of wchar_t if wchar_t is signed char or unsigned
4569 char. */
4570 bool char_array = (typ1 == char_type_node
4571 || typ1 == signed_char_type_node
4572 || typ1 == unsigned_char_type_node);
4573 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4574 if (char_array || wchar_array)
4575 {
4576 struct c_expr expr;
4577 bool char_string;
4578 expr.value = inside_init;
4579 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4580 maybe_warn_string_init (type, expr);
4581
4582 char_string
4583 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4584 == char_type_node);
4585
4586 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4587 TYPE_MAIN_VARIANT (type)))
4588 return inside_init;
4589
4590 if (!wchar_array && !char_string)
4591 {
4592 error_init ("char-array initialized from wide string");
4593 return error_mark_node;
4594 }
4595 if (char_string && !char_array)
4596 {
4597 error_init ("wchar_t-array initialized from non-wide string");
4598 return error_mark_node;
4599 }
4600
4601 TREE_TYPE (inside_init) = type;
4602 if (TYPE_DOMAIN (type) != 0
4603 && TYPE_SIZE (type) != 0
4604 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4605 /* Subtract 1 (or sizeof (wchar_t))
4606 because it's ok to ignore the terminating null char
4607 that is counted in the length of the constant. */
4608 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4609 TREE_STRING_LENGTH (inside_init)
4610 - ((TYPE_PRECISION (typ1)
4611 != TYPE_PRECISION (char_type_node))
4612 ? (TYPE_PRECISION (wchar_type_node)
4613 / BITS_PER_UNIT)
4614 : 1)))
4615 pedwarn_init ("initializer-string for array of chars is too long");
4616
4617 return inside_init;
4618 }
4619 else if (INTEGRAL_TYPE_P (typ1))
4620 {
4621 error_init ("array of inappropriate type initialized "
4622 "from string constant");
4623 return error_mark_node;
4624 }
4625 }
4626
4627 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4628 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4629 below and handle as a constructor. */
4630 if (code == VECTOR_TYPE
4631 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
| 3897 return convert (type, rhs);
3898 /* Arithmetic types all interconvert, and enum is treated like int. */
3899 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3900 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3901 || codel == BOOLEAN_TYPE)
3902 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3903 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3904 || coder == BOOLEAN_TYPE))
3905 return convert_and_check (type, rhs);
3906
3907 /* Aggregates in different TUs might need conversion. */
3908 if ((codel == RECORD_TYPE || codel == UNION_TYPE)
3909 && codel == coder
3910 && comptypes (type, rhstype))
3911 return convert_and_check (type, rhs);
3912
3913 /* Conversion to a transparent union from its member types.
3914 This applies only to function arguments. */
3915 if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3916 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3917 {
3918 tree memb, marginal_memb = NULL_TREE;
3919
3920 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb))
3921 {
3922 tree memb_type = TREE_TYPE (memb);
3923
3924 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3925 TYPE_MAIN_VARIANT (rhstype)))
3926 break;
3927
3928 if (TREE_CODE (memb_type) != POINTER_TYPE)
3929 continue;
3930
3931 if (coder == POINTER_TYPE)
3932 {
3933 tree ttl = TREE_TYPE (memb_type);
3934 tree ttr = TREE_TYPE (rhstype);
3935
3936 /* Any non-function converts to a [const][volatile] void *
3937 and vice versa; otherwise, targets must be the same.
3938 Meanwhile, the lhs target must have all the qualifiers of
3939 the rhs. */
3940 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3941 || comp_target_types (memb_type, rhstype))
3942 {
3943 /* If this type won't generate any warnings, use it. */
3944 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3945 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3946 && TREE_CODE (ttl) == FUNCTION_TYPE)
3947 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3948 == TYPE_QUALS (ttr))
3949 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3950 == TYPE_QUALS (ttl))))
3951 break;
3952
3953 /* Keep looking for a better type, but remember this one. */
3954 if (!marginal_memb)
3955 marginal_memb = memb;
3956 }
3957 }
3958
3959 /* Can convert integer zero to any pointer type. */
3960 if (null_pointer_constant_p (rhs))
3961 {
3962 rhs = null_pointer_node;
3963 break;
3964 }
3965 }
3966
3967 if (memb || marginal_memb)
3968 {
3969 if (!memb)
3970 {
3971 /* We have only a marginally acceptable member type;
3972 it needs a warning. */
3973 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb));
3974 tree ttr = TREE_TYPE (rhstype);
3975
3976 /* Const and volatile mean something different for function
3977 types, so the usual warnings are not appropriate. */
3978 if (TREE_CODE (ttr) == FUNCTION_TYPE
3979 && TREE_CODE (ttl) == FUNCTION_TYPE)
3980 {
3981 /* Because const and volatile on functions are
3982 restrictions that say the function will not do
3983 certain things, it is okay to use a const or volatile
3984 function where an ordinary one is wanted, but not
3985 vice-versa. */
3986 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3987 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE "
3988 "makes qualified function "
3989 "pointer from unqualified"),
3990 G_("assignment makes qualified "
3991 "function pointer from "
3992 "unqualified"),
3993 G_("initialization makes qualified "
3994 "function pointer from "
3995 "unqualified"),
3996 G_("return makes qualified function "
3997 "pointer from unqualified"));
3998 }
3999 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4000 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4001 "qualifiers from pointer target type"),
4002 G_("assignment discards qualifiers "
4003 "from pointer target type"),
4004 G_("initialization discards qualifiers "
4005 "from pointer target type"),
4006 G_("return discards qualifiers from "
4007 "pointer target type"));
4008
4009 memb = marginal_memb;
4010 }
4011
4012 if (pedantic && (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl)))
4013 pedwarn ("ISO C prohibits argument conversion to union type");
4014
4015 return build_constructor_single (type, memb, rhs);
4016 }
4017 }
4018
4019 /* Conversions among pointers */
4020 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4021 && (coder == codel))
4022 {
4023 tree ttl = TREE_TYPE (type);
4024 tree ttr = TREE_TYPE (rhstype);
4025 tree mvl = ttl;
4026 tree mvr = ttr;
4027 bool is_opaque_pointer;
4028 int target_cmp = 0; /* Cache comp_target_types () result. */
4029
4030 if (TREE_CODE (mvl) != ARRAY_TYPE)
4031 mvl = TYPE_MAIN_VARIANT (mvl);
4032 if (TREE_CODE (mvr) != ARRAY_TYPE)
4033 mvr = TYPE_MAIN_VARIANT (mvr);
4034 /* Opaque pointers are treated like void pointers. */
4035 is_opaque_pointer = (targetm.vector_opaque_p (type)
4036 || targetm.vector_opaque_p (rhstype))
4037 && TREE_CODE (ttl) == VECTOR_TYPE
4038 && TREE_CODE (ttr) == VECTOR_TYPE;
4039
4040 /* C++ does not allow the implicit conversion void* -> T*. However,
4041 for the purpose of reducing the number of false positives, we
4042 tolerate the special case of
4043
4044 int *p = NULL;
4045
4046 where NULL is typically defined in C to be '(void *) 0'. */
4047 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
4048 warning (OPT_Wc___compat, "request for implicit conversion from "
4049 "%qT to %qT not permitted in C++", rhstype, type);
4050
4051 /* Check if the right-hand side has a format attribute but the
4052 left-hand side doesn't. */
4053 if (warn_missing_format_attribute
4054 && check_missing_format_attribute (type, rhstype))
4055 {
4056 switch (errtype)
4057 {
4058 case ic_argpass:
4059 case ic_argpass_nonproto:
4060 warning (OPT_Wmissing_format_attribute,
4061 "argument %d of %qE might be "
4062 "a candidate for a format attribute",
4063 parmnum, rname);
4064 break;
4065 case ic_assign:
4066 warning (OPT_Wmissing_format_attribute,
4067 "assignment left-hand side might be "
4068 "a candidate for a format attribute");
4069 break;
4070 case ic_init:
4071 warning (OPT_Wmissing_format_attribute,
4072 "initialization left-hand side might be "
4073 "a candidate for a format attribute");
4074 break;
4075 case ic_return:
4076 warning (OPT_Wmissing_format_attribute,
4077 "return type might be "
4078 "a candidate for a format attribute");
4079 break;
4080 default:
4081 gcc_unreachable ();
4082 }
4083 }
4084
4085 /* Any non-function converts to a [const][volatile] void *
4086 and vice versa; otherwise, targets must be the same.
4087 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4088 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4089 || (target_cmp = comp_target_types (type, rhstype))
4090 || is_opaque_pointer
4091 || (c_common_unsigned_type (mvl)
4092 == c_common_unsigned_type (mvr)))
4093 {
4094 if (pedantic
4095 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
4096 ||
4097 (VOID_TYPE_P (ttr)
4098 && !null_pointer_constant_p (rhs)
4099 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4100 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
4101 "%qE between function pointer "
4102 "and %<void *%>"),
4103 G_("ISO C forbids assignment between "
4104 "function pointer and %<void *%>"),
4105 G_("ISO C forbids initialization between "
4106 "function pointer and %<void *%>"),
4107 G_("ISO C forbids return between function "
4108 "pointer and %<void *%>"));
4109 /* Const and volatile mean something different for function types,
4110 so the usual warnings are not appropriate. */
4111 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4112 && TREE_CODE (ttl) != FUNCTION_TYPE)
4113 {
4114 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4115 {
4116 /* Types differing only by the presence of the 'volatile'
4117 qualifier are acceptable if the 'volatile' has been added
4118 in by the Objective-C EH machinery. */
4119 if (!objc_type_quals_match (ttl, ttr))
4120 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4121 "qualifiers from pointer target type"),
4122 G_("assignment discards qualifiers "
4123 "from pointer target type"),
4124 G_("initialization discards qualifiers "
4125 "from pointer target type"),
4126 G_("return discards qualifiers from "
4127 "pointer target type"));
4128 }
4129 /* If this is not a case of ignoring a mismatch in signedness,
4130 no warning. */
4131 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4132 || target_cmp)
4133 ;
4134 /* If there is a mismatch, do warn. */
4135 else if (warn_pointer_sign)
4136 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument "
4137 "%d of %qE differ in signedness"),
4138 G_("pointer targets in assignment "
4139 "differ in signedness"),
4140 G_("pointer targets in initialization "
4141 "differ in signedness"),
4142 G_("pointer targets in return differ "
4143 "in signedness"));
4144 }
4145 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4146 && TREE_CODE (ttr) == FUNCTION_TYPE)
4147 {
4148 /* Because const and volatile on functions are restrictions
4149 that say the function will not do certain things,
4150 it is okay to use a const or volatile function
4151 where an ordinary one is wanted, but not vice-versa. */
4152 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4153 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4154 "qualified function pointer "
4155 "from unqualified"),
4156 G_("assignment makes qualified function "
4157 "pointer from unqualified"),
4158 G_("initialization makes qualified "
4159 "function pointer from unqualified"),
4160 G_("return makes qualified function "
4161 "pointer from unqualified"));
4162 }
4163 }
4164 else
4165 /* Avoid warning about the volatile ObjC EH puts on decls. */
4166 if (!objc_ok)
4167 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from "
4168 "incompatible pointer type"),
4169 G_("assignment from incompatible pointer type"),
4170 G_("initialization from incompatible "
4171 "pointer type"),
4172 G_("return from incompatible pointer type"));
4173
4174 return convert (type, rhs);
4175 }
4176 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
4177 {
4178 /* ??? This should not be an error when inlining calls to
4179 unprototyped functions. */
4180 error ("invalid use of non-lvalue array");
4181 return error_mark_node;
4182 }
4183 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4184 {
4185 /* An explicit constant 0 can convert to a pointer,
4186 or one that results from arithmetic, even including
4187 a cast to integer type. */
4188 if (!null_pointer_constant_p (rhs))
4189 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4190 "pointer from integer without a cast"),
4191 G_("assignment makes pointer from integer "
4192 "without a cast"),
4193 G_("initialization makes pointer from "
4194 "integer without a cast"),
4195 G_("return makes pointer from integer "
4196 "without a cast"));
4197
4198 return convert (type, rhs);
4199 }
4200 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4201 {
4202 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer "
4203 "from pointer without a cast"),
4204 G_("assignment makes integer from pointer "
4205 "without a cast"),
4206 G_("initialization makes integer from pointer "
4207 "without a cast"),
4208 G_("return makes integer from pointer "
4209 "without a cast"));
4210 return convert (type, rhs);
4211 }
4212 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
4213 return convert (type, rhs);
4214
4215 switch (errtype)
4216 {
4217 case ic_argpass:
4218 case ic_argpass_nonproto:
4219 /* ??? This should not be an error when inlining calls to
4220 unprototyped functions. */
4221 error ("incompatible type for argument %d of %qE", parmnum, rname);
4222 break;
4223 case ic_assign:
4224 error ("incompatible types in assignment");
4225 break;
4226 case ic_init:
4227 error ("incompatible types in initialization");
4228 break;
4229 case ic_return:
4230 error ("incompatible types in return");
4231 break;
4232 default:
4233 gcc_unreachable ();
4234 }
4235
4236 return error_mark_node;
4237}
4238
4239/* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
4240 is used for error and warning reporting and indicates which argument
4241 is being processed. */
4242
4243tree
4244c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
4245{
4246 tree ret, type;
4247
4248 /* If FN was prototyped at the call site, the value has been converted
4249 already in convert_arguments.
4250 However, we might see a prototype now that was not in place when
4251 the function call was seen, so check that the VALUE actually matches
4252 PARM before taking an early exit. */
4253 if (!value
4254 || (TYPE_ARG_TYPES (TREE_TYPE (fn))
4255 && (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
4256 == TYPE_MAIN_VARIANT (TREE_TYPE (value)))))
4257 return value;
4258
4259 type = TREE_TYPE (parm);
4260 ret = convert_for_assignment (type, value,
4261 ic_argpass_nonproto, fn,
4262 fn, argnum);
4263 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
4264 && INTEGRAL_TYPE_P (type)
4265 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
4266 ret = default_conversion (ret);
4267 return ret;
4268}
4269
4270/* If VALUE is a compound expr all of whose expressions are constant, then
4271 return its value. Otherwise, return error_mark_node.
4272
4273 This is for handling COMPOUND_EXPRs as initializer elements
4274 which is allowed with a warning when -pedantic is specified. */
4275
4276static tree
4277valid_compound_expr_initializer (tree value, tree endtype)
4278{
4279 if (TREE_CODE (value) == COMPOUND_EXPR)
4280 {
4281 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4282 == error_mark_node)
4283 return error_mark_node;
4284 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4285 endtype);
4286 }
4287 else if (!initializer_constant_valid_p (value, endtype))
4288 return error_mark_node;
4289 else
4290 return value;
4291}
4292
4293/* Perform appropriate conversions on the initial value of a variable,
4294 store it in the declaration DECL,
4295 and print any error messages that are appropriate.
4296 If the init is invalid, store an ERROR_MARK. */
4297
4298void
4299store_init_value (tree decl, tree init)
4300{
4301 tree value, type;
4302
4303 /* If variable's type was invalidly declared, just ignore it. */
4304
4305 type = TREE_TYPE (decl);
4306 if (TREE_CODE (type) == ERROR_MARK)
4307 return;
4308
4309 /* Digest the specified initializer into an expression. */
4310
4311 value = digest_init (type, init, true, TREE_STATIC (decl));
4312
4313 /* Store the expression if valid; else report error. */
4314
4315 if (!in_system_header
4316 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4317 warning (OPT_Wtraditional, "traditional C rejects automatic "
4318 "aggregate initialization");
4319
4320 DECL_INITIAL (decl) = value;
4321
4322 /* ANSI wants warnings about out-of-range constant initializers. */
4323 STRIP_TYPE_NOPS (value);
4324 constant_expression_warning (value);
4325
4326 /* Check if we need to set array size from compound literal size. */
4327 if (TREE_CODE (type) == ARRAY_TYPE
4328 && TYPE_DOMAIN (type) == 0
4329 && value != error_mark_node)
4330 {
4331 tree inside_init = init;
4332
4333 STRIP_TYPE_NOPS (inside_init);
4334 inside_init = fold (inside_init);
4335
4336 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4337 {
4338 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4339
4340 if (TYPE_DOMAIN (TREE_TYPE (cldecl)))
4341 {
4342 /* For int foo[] = (int [3]){1}; we need to set array size
4343 now since later on array initializer will be just the
4344 brace enclosed list of the compound literal. */
4345 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4346 TREE_TYPE (decl) = type;
4347 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl));
4348 layout_type (type);
4349 layout_decl (cldecl, 0);
4350 }
4351 }
4352 }
4353}
4354
4355/* Methods for storing and printing names for error messages. */
4356
4357/* Implement a spelling stack that allows components of a name to be pushed
4358 and popped. Each element on the stack is this structure. */
4359
4360struct spelling
4361{
4362 int kind;
4363 union
4364 {
4365 unsigned HOST_WIDE_INT i;
4366 const char *s;
4367 } u;
4368};
4369
4370#define SPELLING_STRING 1
4371#define SPELLING_MEMBER 2
4372#define SPELLING_BOUNDS 3
4373
4374static struct spelling *spelling; /* Next stack element (unused). */
4375static struct spelling *spelling_base; /* Spelling stack base. */
4376static int spelling_size; /* Size of the spelling stack. */
4377
4378/* Macros to save and restore the spelling stack around push_... functions.
4379 Alternative to SAVE_SPELLING_STACK. */
4380
4381#define SPELLING_DEPTH() (spelling - spelling_base)
4382#define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4383
4384/* Push an element on the spelling stack with type KIND and assign VALUE
4385 to MEMBER. */
4386
4387#define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4388{ \
4389 int depth = SPELLING_DEPTH (); \
4390 \
4391 if (depth >= spelling_size) \
4392 { \
4393 spelling_size += 10; \
4394 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4395 spelling_size); \
4396 RESTORE_SPELLING_DEPTH (depth); \
4397 } \
4398 \
4399 spelling->kind = (KIND); \
4400 spelling->MEMBER = (VALUE); \
4401 spelling++; \
4402}
4403
4404/* Push STRING on the stack. Printed literally. */
4405
4406static void
4407push_string (const char *string)
4408{
4409 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4410}
4411
4412/* Push a member name on the stack. Printed as '.' STRING. */
4413
4414static void
4415push_member_name (tree decl)
4416{
4417 const char *const string
4418 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4419 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4420}
4421
4422/* Push an array bounds on the stack. Printed as [BOUNDS]. */
4423
4424static void
4425push_array_bounds (unsigned HOST_WIDE_INT bounds)
4426{
4427 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4428}
4429
4430/* Compute the maximum size in bytes of the printed spelling. */
4431
4432static int
4433spelling_length (void)
4434{
4435 int size = 0;
4436 struct spelling *p;
4437
4438 for (p = spelling_base; p < spelling; p++)
4439 {
4440 if (p->kind == SPELLING_BOUNDS)
4441 size += 25;
4442 else
4443 size += strlen (p->u.s) + 1;
4444 }
4445
4446 return size;
4447}
4448
4449/* Print the spelling to BUFFER and return it. */
4450
4451static char *
4452print_spelling (char *buffer)
4453{
4454 char *d = buffer;
4455 struct spelling *p;
4456
4457 for (p = spelling_base; p < spelling; p++)
4458 if (p->kind == SPELLING_BOUNDS)
4459 {
4460 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i);
4461 d += strlen (d);
4462 }
4463 else
4464 {
4465 const char *s;
4466 if (p->kind == SPELLING_MEMBER)
4467 *d++ = '.';
4468 for (s = p->u.s; (*d = *s++); d++)
4469 ;
4470 }
4471 *d++ = '\0';
4472 return buffer;
4473}
4474
4475/* Issue an error message for a bad initializer component.
4476 MSGID identifies the message.
4477 The component name is taken from the spelling stack. */
4478
4479void
4480error_init (const char *msgid)
4481{
4482 char *ofwhat;
4483
4484 error ("%s", _(msgid));
4485 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4486 if (*ofwhat)
4487 error ("(near initialization for %qs)", ofwhat);
4488}
4489
4490/* Issue a pedantic warning for a bad initializer component.
4491 MSGID identifies the message.
4492 The component name is taken from the spelling stack. */
4493
4494void
4495pedwarn_init (const char *msgid)
4496{
4497 char *ofwhat;
4498
4499 pedwarn ("%s", _(msgid));
4500 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4501 if (*ofwhat)
4502 pedwarn ("(near initialization for %qs)", ofwhat);
4503}
4504
4505/* Issue a warning for a bad initializer component.
4506 MSGID identifies the message.
4507 The component name is taken from the spelling stack. */
4508
4509static void
4510warning_init (const char *msgid)
4511{
4512 char *ofwhat;
4513
4514 warning (0, "%s", _(msgid));
4515 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4516 if (*ofwhat)
4517 warning (0, "(near initialization for %qs)", ofwhat);
4518}
4519
4520/* If TYPE is an array type and EXPR is a parenthesized string
4521 constant, warn if pedantic that EXPR is being used to initialize an
4522 object of type TYPE. */
4523
4524void
4525maybe_warn_string_init (tree type, struct c_expr expr)
4526{
4527 if (pedantic
4528 && TREE_CODE (type) == ARRAY_TYPE
4529 && TREE_CODE (expr.value) == STRING_CST
4530 && expr.original_code != STRING_CST)
4531 pedwarn_init ("array initialized from parenthesized string constant");
4532}
4533
4534/* Digest the parser output INIT as an initializer for type TYPE.
4535 Return a C expression of type TYPE to represent the initial value.
4536
4537 If INIT is a string constant, STRICT_STRING is true if it is
4538 unparenthesized or we should not warn here for it being parenthesized.
4539 For other types of INIT, STRICT_STRING is not used.
4540
4541 REQUIRE_CONSTANT requests an error if non-constant initializers or
4542 elements are seen. */
4543
4544static tree
4545digest_init (tree type, tree init, bool strict_string, int require_constant)
4546{
4547 enum tree_code code = TREE_CODE (type);
4548 tree inside_init = init;
4549
4550 if (type == error_mark_node
4551 || !init
4552 || init == error_mark_node
4553 || TREE_TYPE (init) == error_mark_node)
4554 return error_mark_node;
4555
4556 STRIP_TYPE_NOPS (inside_init);
4557
4558 inside_init = fold (inside_init);
4559
4560 /* Initialization of an array of chars from a string constant
4561 optionally enclosed in braces. */
4562
4563 if (code == ARRAY_TYPE && inside_init
4564 && TREE_CODE (inside_init) == STRING_CST)
4565 {
4566 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4567 /* Note that an array could be both an array of character type
4568 and an array of wchar_t if wchar_t is signed char or unsigned
4569 char. */
4570 bool char_array = (typ1 == char_type_node
4571 || typ1 == signed_char_type_node
4572 || typ1 == unsigned_char_type_node);
4573 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4574 if (char_array || wchar_array)
4575 {
4576 struct c_expr expr;
4577 bool char_string;
4578 expr.value = inside_init;
4579 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4580 maybe_warn_string_init (type, expr);
4581
4582 char_string
4583 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4584 == char_type_node);
4585
4586 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4587 TYPE_MAIN_VARIANT (type)))
4588 return inside_init;
4589
4590 if (!wchar_array && !char_string)
4591 {
4592 error_init ("char-array initialized from wide string");
4593 return error_mark_node;
4594 }
4595 if (char_string && !char_array)
4596 {
4597 error_init ("wchar_t-array initialized from non-wide string");
4598 return error_mark_node;
4599 }
4600
4601 TREE_TYPE (inside_init) = type;
4602 if (TYPE_DOMAIN (type) != 0
4603 && TYPE_SIZE (type) != 0
4604 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4605 /* Subtract 1 (or sizeof (wchar_t))
4606 because it's ok to ignore the terminating null char
4607 that is counted in the length of the constant. */
4608 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4609 TREE_STRING_LENGTH (inside_init)
4610 - ((TYPE_PRECISION (typ1)
4611 != TYPE_PRECISION (char_type_node))
4612 ? (TYPE_PRECISION (wchar_type_node)
4613 / BITS_PER_UNIT)
4614 : 1)))
4615 pedwarn_init ("initializer-string for array of chars is too long");
4616
4617 return inside_init;
4618 }
4619 else if (INTEGRAL_TYPE_P (typ1))
4620 {
4621 error_init ("array of inappropriate type initialized "
4622 "from string constant");
4623 return error_mark_node;
4624 }
4625 }
4626
4627 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4628 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4629 below and handle as a constructor. */
4630 if (code == VECTOR_TYPE
4631 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
|
4632 && vector_types_convertible_p (TREE_TYPE (inside_init), type)
| 4632 && vector_types_convertible_p (TREE_TYPE (inside_init), type, true)
|
4633 && TREE_CONSTANT (inside_init))
4634 {
4635 if (TREE_CODE (inside_init) == VECTOR_CST
4636 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4637 TYPE_MAIN_VARIANT (type)))
4638 return inside_init;
4639
4640 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4641 {
4642 unsigned HOST_WIDE_INT ix;
4643 tree value;
4644 bool constant_p = true;
4645
4646 /* Iterate through elements and check if all constructor
4647 elements are *_CSTs. */
4648 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value)
4649 if (!CONSTANT_CLASS_P (value))
4650 {
4651 constant_p = false;
4652 break;
4653 }
4654
4655 if (constant_p)
4656 return build_vector_from_ctor (type,
4657 CONSTRUCTOR_ELTS (inside_init));
4658 }
4659 }
4660
4661 /* Any type can be initialized
4662 from an expression of the same type, optionally with braces. */
4663
4664 if (inside_init && TREE_TYPE (inside_init) != 0
4665 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4666 TYPE_MAIN_VARIANT (type))
4667 || (code == ARRAY_TYPE
4668 && comptypes (TREE_TYPE (inside_init), type))
4669 || (code == VECTOR_TYPE
4670 && comptypes (TREE_TYPE (inside_init), type))
4671 || (code == POINTER_TYPE
4672 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4673 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4674 TREE_TYPE (type)))))
4675 {
4676 if (code == POINTER_TYPE)
4677 {
4678 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4679 {
4680 if (TREE_CODE (inside_init) == STRING_CST
4681 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4682 inside_init = array_to_pointer_conversion (inside_init);
4683 else
4684 {
4685 error_init ("invalid use of non-lvalue array");
4686 return error_mark_node;
4687 }
4688 }
4689 }
4690
4691 if (code == VECTOR_TYPE)
4692 /* Although the types are compatible, we may require a
4693 conversion. */
4694 inside_init = convert (type, inside_init);
4695
4696 if (require_constant
4697 && (code == VECTOR_TYPE || !flag_isoc99)
4698 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4699 {
4700 /* As an extension, allow initializing objects with static storage
4701 duration with compound literals (which are then treated just as
4702 the brace enclosed list they contain). Also allow this for
4703 vectors, as we can only assign them with compound literals. */
4704 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4705 inside_init = DECL_INITIAL (decl);
4706 }
4707
4708 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4709 && TREE_CODE (inside_init) != CONSTRUCTOR)
4710 {
4711 error_init ("array initialized from non-constant array expression");
4712 return error_mark_node;
4713 }
4714
4715 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4716 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4717
4718 /* Compound expressions can only occur here if -pedantic or
4719 -pedantic-errors is specified. In the later case, we always want
4720 an error. In the former case, we simply want a warning. */
4721 if (require_constant && pedantic
4722 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4723 {
4724 inside_init
4725 = valid_compound_expr_initializer (inside_init,
4726 TREE_TYPE (inside_init));
4727 if (inside_init == error_mark_node)
4728 error_init ("initializer element is not constant");
4729 else
4730 pedwarn_init ("initializer element is not constant");
4731 if (flag_pedantic_errors)
4732 inside_init = error_mark_node;
4733 }
4734 else if (require_constant
4735 && !initializer_constant_valid_p (inside_init,
4736 TREE_TYPE (inside_init)))
4737 {
4738 error_init ("initializer element is not constant");
4739 inside_init = error_mark_node;
4740 }
4741
4742 /* Added to enable additional -Wmissing-format-attribute warnings. */
4743 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE)
4744 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE,
4745 NULL_TREE, 0);
4746 return inside_init;
4747 }
4748
4749 /* Handle scalar types, including conversions. */
4750
4751 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4752 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4753 || code == VECTOR_TYPE)
4754 {
4755 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
4756 && (TREE_CODE (init) == STRING_CST
4757 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
4758 init = array_to_pointer_conversion (init);
4759 inside_init
4760 = convert_for_assignment (type, init, ic_init,
4761 NULL_TREE, NULL_TREE, 0);
4762
4763 /* Check to see if we have already given an error message. */
4764 if (inside_init == error_mark_node)
4765 ;
4766 else if (require_constant && !TREE_CONSTANT (inside_init))
4767 {
4768 error_init ("initializer element is not constant");
4769 inside_init = error_mark_node;
4770 }
4771 else if (require_constant
4772 && !initializer_constant_valid_p (inside_init,
4773 TREE_TYPE (inside_init)))
4774 {
4775 error_init ("initializer element is not computable at load time");
4776 inside_init = error_mark_node;
4777 }
4778
4779 return inside_init;
4780 }
4781
4782 /* Come here only for records and arrays. */
4783
4784 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4785 {
4786 error_init ("variable-sized object may not be initialized");
4787 return error_mark_node;
4788 }
4789
4790 error_init ("invalid initializer");
4791 return error_mark_node;
4792}
4793
4794/* Handle initializers that use braces. */
4795
4796/* Type of object we are accumulating a constructor for.
4797 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4798static tree constructor_type;
4799
4800/* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4801 left to fill. */
4802static tree constructor_fields;
4803
4804/* For an ARRAY_TYPE, this is the specified index
4805 at which to store the next element we get. */
4806static tree constructor_index;
4807
4808/* For an ARRAY_TYPE, this is the maximum index. */
4809static tree constructor_max_index;
4810
4811/* For a RECORD_TYPE, this is the first field not yet written out. */
4812static tree constructor_unfilled_fields;
4813
4814/* For an ARRAY_TYPE, this is the index of the first element
4815 not yet written out. */
4816static tree constructor_unfilled_index;
4817
4818/* In a RECORD_TYPE, the byte index of the next consecutive field.
4819 This is so we can generate gaps between fields, when appropriate. */
4820static tree constructor_bit_index;
4821
4822/* If we are saving up the elements rather than allocating them,
4823 this is the list of elements so far (in reverse order,
4824 most recent first). */
4825static VEC(constructor_elt,gc) *constructor_elements;
4826
4827/* 1 if constructor should be incrementally stored into a constructor chain,
4828 0 if all the elements should be kept in AVL tree. */
4829static int constructor_incremental;
4830
4831/* 1 if so far this constructor's elements are all compile-time constants. */
4832static int constructor_constant;
4833
4834/* 1 if so far this constructor's elements are all valid address constants. */
4835static int constructor_simple;
4836
4837/* 1 if this constructor is erroneous so far. */
4838static int constructor_erroneous;
4839
4840/* Structure for managing pending initializer elements, organized as an
4841 AVL tree. */
4842
4843struct init_node
4844{
4845 struct init_node *left, *right;
4846 struct init_node *parent;
4847 int balance;
4848 tree purpose;
4849 tree value;
4850};
4851
4852/* Tree of pending elements at this constructor level.
4853 These are elements encountered out of order
4854 which belong at places we haven't reached yet in actually
4855 writing the output.
4856 Will never hold tree nodes across GC runs. */
4857static struct init_node *constructor_pending_elts;
4858
4859/* The SPELLING_DEPTH of this constructor. */
4860static int constructor_depth;
4861
4862/* DECL node for which an initializer is being read.
4863 0 means we are reading a constructor expression
4864 such as (struct foo) {...}. */
4865static tree constructor_decl;
4866
4867/* Nonzero if this is an initializer for a top-level decl. */
4868static int constructor_top_level;
4869
4870/* Nonzero if there were any member designators in this initializer. */
4871static int constructor_designated;
4872
4873/* Nesting depth of designator list. */
4874static int designator_depth;
4875
4876/* Nonzero if there were diagnosed errors in this designator list. */
4877static int designator_erroneous;
4878
4879
4880/* This stack has a level for each implicit or explicit level of
4881 structuring in the initializer, including the outermost one. It
4882 saves the values of most of the variables above. */
4883
4884struct constructor_range_stack;
4885
4886struct constructor_stack
4887{
4888 struct constructor_stack *next;
4889 tree type;
4890 tree fields;
4891 tree index;
4892 tree max_index;
4893 tree unfilled_index;
4894 tree unfilled_fields;
4895 tree bit_index;
4896 VEC(constructor_elt,gc) *elements;
4897 struct init_node *pending_elts;
4898 int offset;
4899 int depth;
4900 /* If value nonzero, this value should replace the entire
4901 constructor at this level. */
4902 struct c_expr replacement_value;
4903 struct constructor_range_stack *range_stack;
4904 char constant;
4905 char simple;
4906 char implicit;
4907 char erroneous;
4908 char outer;
4909 char incremental;
4910 char designated;
4911};
4912
4913static struct constructor_stack *constructor_stack;
4914
4915/* This stack represents designators from some range designator up to
4916 the last designator in the list. */
4917
4918struct constructor_range_stack
4919{
4920 struct constructor_range_stack *next, *prev;
4921 struct constructor_stack *stack;
4922 tree range_start;
4923 tree index;
4924 tree range_end;
4925 tree fields;
4926};
4927
4928static struct constructor_range_stack *constructor_range_stack;
4929
4930/* This stack records separate initializers that are nested.
4931 Nested initializers can't happen in ANSI C, but GNU C allows them
4932 in cases like { ... (struct foo) { ... } ... }. */
4933
4934struct initializer_stack
4935{
4936 struct initializer_stack *next;
4937 tree decl;
4938 struct constructor_stack *constructor_stack;
4939 struct constructor_range_stack *constructor_range_stack;
4940 VEC(constructor_elt,gc) *elements;
4941 struct spelling *spelling;
4942 struct spelling *spelling_base;
4943 int spelling_size;
4944 char top_level;
4945 char require_constant_value;
4946 char require_constant_elements;
4947};
4948
4949static struct initializer_stack *initializer_stack;
4950
4951/* Prepare to parse and output the initializer for variable DECL. */
4952
4953void
4954start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4955{
4956 const char *locus;
4957 struct initializer_stack *p = XNEW (struct initializer_stack);
4958
4959 p->decl = constructor_decl;
4960 p->require_constant_value = require_constant_value;
4961 p->require_constant_elements = require_constant_elements;
4962 p->constructor_stack = constructor_stack;
4963 p->constructor_range_stack = constructor_range_stack;
4964 p->elements = constructor_elements;
4965 p->spelling = spelling;
4966 p->spelling_base = spelling_base;
4967 p->spelling_size = spelling_size;
4968 p->top_level = constructor_top_level;
4969 p->next = initializer_stack;
4970 initializer_stack = p;
4971
4972 constructor_decl = decl;
4973 constructor_designated = 0;
4974 constructor_top_level = top_level;
4975
4976 if (decl != 0 && decl != error_mark_node)
4977 {
4978 require_constant_value = TREE_STATIC (decl);
4979 require_constant_elements
4980 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4981 /* For a scalar, you can always use any value to initialize,
4982 even within braces. */
4983 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4984 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4985 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4986 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4987 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4988 }
4989 else
4990 {
4991 require_constant_value = 0;
4992 require_constant_elements = 0;
4993 locus = "(anonymous)";
4994 }
4995
4996 constructor_stack = 0;
4997 constructor_range_stack = 0;
4998
4999 missing_braces_mentioned = 0;
5000
5001 spelling_base = 0;
5002 spelling_size = 0;
5003 RESTORE_SPELLING_DEPTH (0);
5004
5005 if (locus)
5006 push_string (locus);
5007}
5008
5009void
5010finish_init (void)
5011{
5012 struct initializer_stack *p = initializer_stack;
5013
5014 /* Free the whole constructor stack of this initializer. */
5015 while (constructor_stack)
5016 {
5017 struct constructor_stack *q = constructor_stack;
5018 constructor_stack = q->next;
5019 free (q);
5020 }
5021
5022 gcc_assert (!constructor_range_stack);
5023
5024 /* Pop back to the data of the outer initializer (if any). */
5025 free (spelling_base);
5026
5027 constructor_decl = p->decl;
5028 require_constant_value = p->require_constant_value;
5029 require_constant_elements = p->require_constant_elements;
5030 constructor_stack = p->constructor_stack;
5031 constructor_range_stack = p->constructor_range_stack;
5032 constructor_elements = p->elements;
5033 spelling = p->spelling;
5034 spelling_base = p->spelling_base;
5035 spelling_size = p->spelling_size;
5036 constructor_top_level = p->top_level;
5037 initializer_stack = p->next;
5038 free (p);
5039}
5040
5041/* Call here when we see the initializer is surrounded by braces.
5042 This is instead of a call to push_init_level;
5043 it is matched by a call to pop_init_level.
5044
5045 TYPE is the type to initialize, for a constructor expression.
5046 For an initializer for a decl, TYPE is zero. */
5047
5048void
5049really_start_incremental_init (tree type)
5050{
5051 struct constructor_stack *p = XNEW (struct constructor_stack);
5052
5053 if (type == 0)
5054 type = TREE_TYPE (constructor_decl);
5055
5056 if (targetm.vector_opaque_p (type))
5057 error ("opaque vector types cannot be initialized");
5058
5059 p->type = constructor_type;
5060 p->fields = constructor_fields;
5061 p->index = constructor_index;
5062 p->max_index = constructor_max_index;
5063 p->unfilled_index = constructor_unfilled_index;
5064 p->unfilled_fields = constructor_unfilled_fields;
5065 p->bit_index = constructor_bit_index;
5066 p->elements = constructor_elements;
5067 p->constant = constructor_constant;
5068 p->simple = constructor_simple;
5069 p->erroneous = constructor_erroneous;
5070 p->pending_elts = constructor_pending_elts;
5071 p->depth = constructor_depth;
5072 p->replacement_value.value = 0;
5073 p->replacement_value.original_code = ERROR_MARK;
5074 p->implicit = 0;
5075 p->range_stack = 0;
5076 p->outer = 0;
5077 p->incremental = constructor_incremental;
5078 p->designated = constructor_designated;
5079 p->next = 0;
5080 constructor_stack = p;
5081
5082 constructor_constant = 1;
5083 constructor_simple = 1;
5084 constructor_depth = SPELLING_DEPTH ();
5085 constructor_elements = 0;
5086 constructor_pending_elts = 0;
5087 constructor_type = type;
5088 constructor_incremental = 1;
5089 constructor_designated = 0;
5090 designator_depth = 0;
5091 designator_erroneous = 0;
5092
5093 if (TREE_CODE (constructor_type) == RECORD_TYPE
5094 || TREE_CODE (constructor_type) == UNION_TYPE)
5095 {
5096 constructor_fields = TYPE_FIELDS (constructor_type);
5097 /* Skip any nameless bit fields at the beginning. */
5098 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5099 && DECL_NAME (constructor_fields) == 0)
5100 constructor_fields = TREE_CHAIN (constructor_fields);
5101
5102 constructor_unfilled_fields = constructor_fields;
5103 constructor_bit_index = bitsize_zero_node;
5104 }
5105 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5106 {
5107 if (TYPE_DOMAIN (constructor_type))
5108 {
5109 constructor_max_index
5110 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5111
5112 /* Detect non-empty initializations of zero-length arrays. */
5113 if (constructor_max_index == NULL_TREE
5114 && TYPE_SIZE (constructor_type))
5115 constructor_max_index = build_int_cst (NULL_TREE, -1);
5116
5117 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5118 to initialize VLAs will cause a proper error; avoid tree
5119 checking errors as well by setting a safe value. */
5120 if (constructor_max_index
5121 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5122 constructor_max_index = build_int_cst (NULL_TREE, -1);
5123
5124 constructor_index
5125 = convert (bitsizetype,
5126 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5127 }
5128 else
5129 {
5130 constructor_index = bitsize_zero_node;
5131 constructor_max_index = NULL_TREE;
5132 }
5133
5134 constructor_unfilled_index = constructor_index;
5135 }
5136 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5137 {
5138 /* Vectors are like simple fixed-size arrays. */
5139 constructor_max_index =
5140 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5141 constructor_index = bitsize_zero_node;
5142 constructor_unfilled_index = constructor_index;
5143 }
5144 else
5145 {
5146 /* Handle the case of int x = {5}; */
5147 constructor_fields = constructor_type;
5148 constructor_unfilled_fields = constructor_type;
5149 }
5150}
5151
5152/* Push down into a subobject, for initialization.
5153 If this is for an explicit set of braces, IMPLICIT is 0.
5154 If it is because the next element belongs at a lower level,
5155 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5156
5157void
5158push_init_level (int implicit)
5159{
5160 struct constructor_stack *p;
5161 tree value = NULL_TREE;
5162
5163 /* If we've exhausted any levels that didn't have braces,
5164 pop them now. If implicit == 1, this will have been done in
5165 process_init_element; do not repeat it here because in the case
5166 of excess initializers for an empty aggregate this leads to an
5167 infinite cycle of popping a level and immediately recreating
5168 it. */
5169 if (implicit != 1)
5170 {
5171 while (constructor_stack->implicit)
5172 {
5173 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5174 || TREE_CODE (constructor_type) == UNION_TYPE)
5175 && constructor_fields == 0)
5176 process_init_element (pop_init_level (1));
5177 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5178 && constructor_max_index
5179 && tree_int_cst_lt (constructor_max_index,
5180 constructor_index))
5181 process_init_element (pop_init_level (1));
5182 else
5183 break;
5184 }
5185 }
5186
5187 /* Unless this is an explicit brace, we need to preserve previous
5188 content if any. */
5189 if (implicit)
5190 {
5191 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5192 || TREE_CODE (constructor_type) == UNION_TYPE)
5193 && constructor_fields)
5194 value = find_init_member (constructor_fields);
5195 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5196 value = find_init_member (constructor_index);
5197 }
5198
5199 p = XNEW (struct constructor_stack);
5200 p->type = constructor_type;
5201 p->fields = constructor_fields;
5202 p->index = constructor_index;
5203 p->max_index = constructor_max_index;
5204 p->unfilled_index = constructor_unfilled_index;
5205 p->unfilled_fields = constructor_unfilled_fields;
5206 p->bit_index = constructor_bit_index;
5207 p->elements = constructor_elements;
5208 p->constant = constructor_constant;
5209 p->simple = constructor_simple;
5210 p->erroneous = constructor_erroneous;
5211 p->pending_elts = constructor_pending_elts;
5212 p->depth = constructor_depth;
5213 p->replacement_value.value = 0;
5214 p->replacement_value.original_code = ERROR_MARK;
5215 p->implicit = implicit;
5216 p->outer = 0;
5217 p->incremental = constructor_incremental;
5218 p->designated = constructor_designated;
5219 p->next = constructor_stack;
5220 p->range_stack = 0;
5221 constructor_stack = p;
5222
5223 constructor_constant = 1;
5224 constructor_simple = 1;
5225 constructor_depth = SPELLING_DEPTH ();
5226 constructor_elements = 0;
5227 constructor_incremental = 1;
5228 constructor_designated = 0;
5229 constructor_pending_elts = 0;
5230 if (!implicit)
5231 {
5232 p->range_stack = constructor_range_stack;
5233 constructor_range_stack = 0;
5234 designator_depth = 0;
5235 designator_erroneous = 0;
5236 }
5237
5238 /* Don't die if an entire brace-pair level is superfluous
5239 in the containing level. */
5240 if (constructor_type == 0)
5241 ;
5242 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5243 || TREE_CODE (constructor_type) == UNION_TYPE)
5244 {
5245 /* Don't die if there are extra init elts at the end. */
5246 if (constructor_fields == 0)
5247 constructor_type = 0;
5248 else
5249 {
5250 constructor_type = TREE_TYPE (constructor_fields);
5251 push_member_name (constructor_fields);
5252 constructor_depth++;
5253 }
5254 }
5255 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5256 {
5257 constructor_type = TREE_TYPE (constructor_type);
5258 push_array_bounds (tree_low_cst (constructor_index, 1));
5259 constructor_depth++;
5260 }
5261
5262 if (constructor_type == 0)
5263 {
5264 error_init ("extra brace group at end of initializer");
5265 constructor_fields = 0;
5266 constructor_unfilled_fields = 0;
5267 return;
5268 }
5269
5270 if (value && TREE_CODE (value) == CONSTRUCTOR)
5271 {
5272 constructor_constant = TREE_CONSTANT (value);
5273 constructor_simple = TREE_STATIC (value);
5274 constructor_elements = CONSTRUCTOR_ELTS (value);
5275 if (!VEC_empty (constructor_elt, constructor_elements)
5276 && (TREE_CODE (constructor_type) == RECORD_TYPE
5277 || TREE_CODE (constructor_type) == ARRAY_TYPE))
5278 set_nonincremental_init ();
5279 }
5280
5281 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
5282 {
5283 missing_braces_mentioned = 1;
5284 warning_init ("missing braces around initializer");
5285 }
5286
5287 if (TREE_CODE (constructor_type) == RECORD_TYPE
5288 || TREE_CODE (constructor_type) == UNION_TYPE)
5289 {
5290 constructor_fields = TYPE_FIELDS (constructor_type);
5291 /* Skip any nameless bit fields at the beginning. */
5292 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5293 && DECL_NAME (constructor_fields) == 0)
5294 constructor_fields = TREE_CHAIN (constructor_fields);
5295
5296 constructor_unfilled_fields = constructor_fields;
5297 constructor_bit_index = bitsize_zero_node;
5298 }
5299 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5300 {
5301 /* Vectors are like simple fixed-size arrays. */
5302 constructor_max_index =
5303 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5304 constructor_index = convert (bitsizetype, integer_zero_node);
5305 constructor_unfilled_index = constructor_index;
5306 }
5307 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5308 {
5309 if (TYPE_DOMAIN (constructor_type))
5310 {
5311 constructor_max_index
5312 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5313
5314 /* Detect non-empty initializations of zero-length arrays. */
5315 if (constructor_max_index == NULL_TREE
5316 && TYPE_SIZE (constructor_type))
5317 constructor_max_index = build_int_cst (NULL_TREE, -1);
5318
5319 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5320 to initialize VLAs will cause a proper error; avoid tree
5321 checking errors as well by setting a safe value. */
5322 if (constructor_max_index
5323 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5324 constructor_max_index = build_int_cst (NULL_TREE, -1);
5325
5326 constructor_index
5327 = convert (bitsizetype,
5328 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5329 }
5330 else
5331 constructor_index = bitsize_zero_node;
5332
5333 constructor_unfilled_index = constructor_index;
5334 if (value && TREE_CODE (value) == STRING_CST)
5335 {
5336 /* We need to split the char/wchar array into individual
5337 characters, so that we don't have to special case it
5338 everywhere. */
5339 set_nonincremental_init_from_string (value);
5340 }
5341 }
5342 else
5343 {
5344 if (constructor_type != error_mark_node)
5345 warning_init ("braces around scalar initializer");
5346 constructor_fields = constructor_type;
5347 constructor_unfilled_fields = constructor_type;
5348 }
5349}
5350
5351/* At the end of an implicit or explicit brace level,
5352 finish up that level of constructor. If a single expression
5353 with redundant braces initialized that level, return the
5354 c_expr structure for that expression. Otherwise, the original_code
5355 element is set to ERROR_MARK.
5356 If we were outputting the elements as they are read, return 0 as the value
5357 from inner levels (process_init_element ignores that),
5358 but return error_mark_node as the value from the outermost level
5359 (that's what we want to put in DECL_INITIAL).
5360 Otherwise, return a CONSTRUCTOR expression as the value. */
5361
5362struct c_expr
5363pop_init_level (int implicit)
5364{
5365 struct constructor_stack *p;
5366 struct c_expr ret;
5367 ret.value = 0;
5368 ret.original_code = ERROR_MARK;
5369
5370 if (implicit == 0)
5371 {
5372 /* When we come to an explicit close brace,
5373 pop any inner levels that didn't have explicit braces. */
5374 while (constructor_stack->implicit)
5375 process_init_element (pop_init_level (1));
5376
5377 gcc_assert (!constructor_range_stack);
5378 }
5379
5380 /* Now output all pending elements. */
5381 constructor_incremental = 1;
5382 output_pending_init_elements (1);
5383
5384 p = constructor_stack;
5385
5386 /* Error for initializing a flexible array member, or a zero-length
5387 array member in an inappropriate context. */
5388 if (constructor_type && constructor_fields
5389 && TREE_CODE (constructor_type) == ARRAY_TYPE
5390 && TYPE_DOMAIN (constructor_type)
5391 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5392 {
5393 /* Silently discard empty initializations. The parser will
5394 already have pedwarned for empty brackets. */
5395 if (integer_zerop (constructor_unfilled_index))
5396 constructor_type = NULL_TREE;
5397 else
5398 {
5399 gcc_assert (!TYPE_SIZE (constructor_type));
5400
5401 if (constructor_depth > 2)
5402 error_init ("initialization of flexible array member in a nested context");
5403 else if (pedantic)
5404 pedwarn_init ("initialization of a flexible array member");
5405
5406 /* We have already issued an error message for the existence
5407 of a flexible array member not at the end of the structure.
5408 Discard the initializer so that we do not die later. */
5409 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5410 constructor_type = NULL_TREE;
5411 }
5412 }
5413
5414 /* Warn when some struct elements are implicitly initialized to zero. */
5415 if (warn_missing_field_initializers
5416 && constructor_type
5417 && TREE_CODE (constructor_type) == RECORD_TYPE
5418 && constructor_unfilled_fields)
5419 {
5420 /* Do not warn for flexible array members or zero-length arrays. */
5421 while (constructor_unfilled_fields
5422 && (!DECL_SIZE (constructor_unfilled_fields)
5423 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5424 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5425
5426 /* Do not warn if this level of the initializer uses member
5427 designators; it is likely to be deliberate. */
5428 if (constructor_unfilled_fields && !constructor_designated)
5429 {
5430 push_member_name (constructor_unfilled_fields);
5431 warning_init ("missing initializer");
5432 RESTORE_SPELLING_DEPTH (constructor_depth);
5433 }
5434 }
5435
5436 /* Pad out the end of the structure. */
5437 if (p->replacement_value.value)
5438 /* If this closes a superfluous brace pair,
5439 just pass out the element between them. */
5440 ret = p->replacement_value;
5441 else if (constructor_type == 0)
5442 ;
5443 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5444 && TREE_CODE (constructor_type) != UNION_TYPE
5445 && TREE_CODE (constructor_type) != ARRAY_TYPE
5446 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5447 {
5448 /* A nonincremental scalar initializer--just return
5449 the element, after verifying there is just one. */
5450 if (VEC_empty (constructor_elt,constructor_elements))
5451 {
5452 if (!constructor_erroneous)
5453 error_init ("empty scalar initializer");
5454 ret.value = error_mark_node;
5455 }
5456 else if (VEC_length (constructor_elt,constructor_elements) != 1)
5457 {
5458 error_init ("extra elements in scalar initializer");
5459 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5460 }
5461 else
5462 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5463 }
5464 else
5465 {
5466 if (constructor_erroneous)
5467 ret.value = error_mark_node;
5468 else
5469 {
5470 ret.value = build_constructor (constructor_type,
5471 constructor_elements);
5472 if (constructor_constant)
5473 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5474 if (constructor_constant && constructor_simple)
5475 TREE_STATIC (ret.value) = 1;
5476 }
5477 }
5478
5479 constructor_type = p->type;
5480 constructor_fields = p->fields;
5481 constructor_index = p->index;
5482 constructor_max_index = p->max_index;
5483 constructor_unfilled_index = p->unfilled_index;
5484 constructor_unfilled_fields = p->unfilled_fields;
5485 constructor_bit_index = p->bit_index;
5486 constructor_elements = p->elements;
5487 constructor_constant = p->constant;
5488 constructor_simple = p->simple;
5489 constructor_erroneous = p->erroneous;
5490 constructor_incremental = p->incremental;
5491 constructor_designated = p->designated;
5492 constructor_pending_elts = p->pending_elts;
5493 constructor_depth = p->depth;
5494 if (!p->implicit)
5495 constructor_range_stack = p->range_stack;
5496 RESTORE_SPELLING_DEPTH (constructor_depth);
5497
5498 constructor_stack = p->next;
5499 free (p);
5500
5501 if (ret.value == 0 && constructor_stack == 0)
5502 ret.value = error_mark_node;
5503 return ret;
5504}
5505
5506/* Common handling for both array range and field name designators.
5507 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5508
5509static int
5510set_designator (int array)
5511{
5512 tree subtype;
5513 enum tree_code subcode;
5514
5515 /* Don't die if an entire brace-pair level is superfluous
5516 in the containing level. */
5517 if (constructor_type == 0)
5518 return 1;
5519
5520 /* If there were errors in this designator list already, bail out
5521 silently. */
5522 if (designator_erroneous)
5523 return 1;
5524
5525 if (!designator_depth)
5526 {
5527 gcc_assert (!constructor_range_stack);
5528
5529 /* Designator list starts at the level of closest explicit
5530 braces. */
5531 while (constructor_stack->implicit)
5532 process_init_element (pop_init_level (1));
5533 constructor_designated = 1;
5534 return 0;
5535 }
5536
5537 switch (TREE_CODE (constructor_type))
5538 {
5539 case RECORD_TYPE:
5540 case UNION_TYPE:
5541 subtype = TREE_TYPE (constructor_fields);
5542 if (subtype != error_mark_node)
5543 subtype = TYPE_MAIN_VARIANT (subtype);
5544 break;
5545 case ARRAY_TYPE:
5546 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5547 break;
5548 default:
5549 gcc_unreachable ();
5550 }
5551
5552 subcode = TREE_CODE (subtype);
5553 if (array && subcode != ARRAY_TYPE)
5554 {
5555 error_init ("array index in non-array initializer");
5556 return 1;
5557 }
5558 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5559 {
5560 error_init ("field name not in record or union initializer");
5561 return 1;
5562 }
5563
5564 constructor_designated = 1;
5565 push_init_level (2);
5566 return 0;
5567}
5568
5569/* If there are range designators in designator list, push a new designator
5570 to constructor_range_stack. RANGE_END is end of such stack range or
5571 NULL_TREE if there is no range designator at this level. */
5572
5573static void
5574push_range_stack (tree range_end)
5575{
5576 struct constructor_range_stack *p;
5577
5578 p = GGC_NEW (struct constructor_range_stack);
5579 p->prev = constructor_range_stack;
5580 p->next = 0;
5581 p->fields = constructor_fields;
5582 p->range_start = constructor_index;
5583 p->index = constructor_index;
5584 p->stack = constructor_stack;
5585 p->range_end = range_end;
5586 if (constructor_range_stack)
5587 constructor_range_stack->next = p;
5588 constructor_range_stack = p;
5589}
5590
5591/* Within an array initializer, specify the next index to be initialized.
5592 FIRST is that index. If LAST is nonzero, then initialize a range
5593 of indices, running from FIRST through LAST. */
5594
5595void
5596set_init_index (tree first, tree last)
5597{
5598 if (set_designator (1))
5599 return;
5600
5601 designator_erroneous = 1;
5602
5603 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5604 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5605 {
5606 error_init ("array index in initializer not of integer type");
5607 return;
5608 }
5609
5610 if (TREE_CODE (first) != INTEGER_CST)
5611 error_init ("nonconstant array index in initializer");
5612 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5613 error_init ("nonconstant array index in initializer");
5614 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5615 error_init ("array index in non-array initializer");
5616 else if (tree_int_cst_sgn (first) == -1)
5617 error_init ("array index in initializer exceeds array bounds");
5618 else if (constructor_max_index
5619 && tree_int_cst_lt (constructor_max_index, first))
5620 error_init ("array index in initializer exceeds array bounds");
5621 else
5622 {
5623 constructor_index = convert (bitsizetype, first);
5624
5625 if (last)
5626 {
5627 if (tree_int_cst_equal (first, last))
5628 last = 0;
5629 else if (tree_int_cst_lt (last, first))
5630 {
5631 error_init ("empty index range in initializer");
5632 last = 0;
5633 }
5634 else
5635 {
5636 last = convert (bitsizetype, last);
5637 if (constructor_max_index != 0
5638 && tree_int_cst_lt (constructor_max_index, last))
5639 {
5640 error_init ("array index range in initializer exceeds array bounds");
5641 last = 0;
5642 }
5643 }
5644 }
5645
5646 designator_depth++;
5647 designator_erroneous = 0;
5648 if (constructor_range_stack || last)
5649 push_range_stack (last);
5650 }
5651}
5652
5653/* Within a struct initializer, specify the next field to be initialized. */
5654
5655void
5656set_init_label (tree fieldname)
5657{
5658 tree tail;
5659
5660 if (set_designator (0))
5661 return;
5662
5663 designator_erroneous = 1;
5664
5665 if (TREE_CODE (constructor_type) != RECORD_TYPE
5666 && TREE_CODE (constructor_type) != UNION_TYPE)
5667 {
5668 error_init ("field name not in record or union initializer");
5669 return;
5670 }
5671
5672 for (tail = TYPE_FIELDS (constructor_type); tail;
5673 tail = TREE_CHAIN (tail))
5674 {
5675 if (DECL_NAME (tail) == fieldname)
5676 break;
5677 }
5678
5679 if (tail == 0)
5680 error ("unknown field %qE specified in initializer", fieldname);
5681 else
5682 {
5683 constructor_fields = tail;
5684 designator_depth++;
5685 designator_erroneous = 0;
5686 if (constructor_range_stack)
5687 push_range_stack (NULL_TREE);
5688 }
5689}
5690
5691/* Add a new initializer to the tree of pending initializers. PURPOSE
5692 identifies the initializer, either array index or field in a structure.
5693 VALUE is the value of that index or field. */
5694
5695static void
5696add_pending_init (tree purpose, tree value)
5697{
5698 struct init_node *p, **q, *r;
5699
5700 q = &constructor_pending_elts;
5701 p = 0;
5702
5703 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5704 {
5705 while (*q != 0)
5706 {
5707 p = *q;
5708 if (tree_int_cst_lt (purpose, p->purpose))
5709 q = &p->left;
5710 else if (tree_int_cst_lt (p->purpose, purpose))
5711 q = &p->right;
5712 else
5713 {
5714 if (TREE_SIDE_EFFECTS (p->value))
5715 warning_init ("initialized field with side-effects overwritten");
5716 else if (warn_override_init)
5717 warning_init ("initialized field overwritten");
5718 p->value = value;
5719 return;
5720 }
5721 }
5722 }
5723 else
5724 {
5725 tree bitpos;
5726
5727 bitpos = bit_position (purpose);
5728 while (*q != NULL)
5729 {
5730 p = *q;
5731 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5732 q = &p->left;
5733 else if (p->purpose != purpose)
5734 q = &p->right;
5735 else
5736 {
5737 if (TREE_SIDE_EFFECTS (p->value))
5738 warning_init ("initialized field with side-effects overwritten");
5739 else if (warn_override_init)
5740 warning_init ("initialized field overwritten");
5741 p->value = value;
5742 return;
5743 }
5744 }
5745 }
5746
5747 r = GGC_NEW (struct init_node);
5748 r->purpose = purpose;
5749 r->value = value;
5750
5751 *q = r;
5752 r->parent = p;
5753 r->left = 0;
5754 r->right = 0;
5755 r->balance = 0;
5756
5757 while (p)
5758 {
5759 struct init_node *s;
5760
5761 if (r == p->left)
5762 {
5763 if (p->balance == 0)
5764 p->balance = -1;
5765 else if (p->balance < 0)
5766 {
5767 if (r->balance < 0)
5768 {
5769 /* L rotation. */
5770 p->left = r->right;
5771 if (p->left)
5772 p->left->parent = p;
5773 r->right = p;
5774
5775 p->balance = 0;
5776 r->balance = 0;
5777
5778 s = p->parent;
5779 p->parent = r;
5780 r->parent = s;
5781 if (s)
5782 {
5783 if (s->left == p)
5784 s->left = r;
5785 else
5786 s->right = r;
5787 }
5788 else
5789 constructor_pending_elts = r;
5790 }
5791 else
5792 {
5793 /* LR rotation. */
5794 struct init_node *t = r->right;
5795
5796 r->right = t->left;
5797 if (r->right)
5798 r->right->parent = r;
5799 t->left = r;
5800
5801 p->left = t->right;
5802 if (p->left)
5803 p->left->parent = p;
5804 t->right = p;
5805
5806 p->balance = t->balance < 0;
5807 r->balance = -(t->balance > 0);
5808 t->balance = 0;
5809
5810 s = p->parent;
5811 p->parent = t;
5812 r->parent = t;
5813 t->parent = s;
5814 if (s)
5815 {
5816 if (s->left == p)
5817 s->left = t;
5818 else
5819 s->right = t;
5820 }
5821 else
5822 constructor_pending_elts = t;
5823 }
5824 break;
5825 }
5826 else
5827 {
5828 /* p->balance == +1; growth of left side balances the node. */
5829 p->balance = 0;
5830 break;
5831 }
5832 }
5833 else /* r == p->right */
5834 {
5835 if (p->balance == 0)
5836 /* Growth propagation from right side. */
5837 p->balance++;
5838 else if (p->balance > 0)
5839 {
5840 if (r->balance > 0)
5841 {
5842 /* R rotation. */
5843 p->right = r->left;
5844 if (p->right)
5845 p->right->parent = p;
5846 r->left = p;
5847
5848 p->balance = 0;
5849 r->balance = 0;
5850
5851 s = p->parent;
5852 p->parent = r;
5853 r->parent = s;
5854 if (s)
5855 {
5856 if (s->left == p)
5857 s->left = r;
5858 else
5859 s->right = r;
5860 }
5861 else
5862 constructor_pending_elts = r;
5863 }
5864 else /* r->balance == -1 */
5865 {
5866 /* RL rotation */
5867 struct init_node *t = r->left;
5868
5869 r->left = t->right;
5870 if (r->left)
5871 r->left->parent = r;
5872 t->right = r;
5873
5874 p->right = t->left;
5875 if (p->right)
5876 p->right->parent = p;
5877 t->left = p;
5878
5879 r->balance = (t->balance < 0);
5880 p->balance = -(t->balance > 0);
5881 t->balance = 0;
5882
5883 s = p->parent;
5884 p->parent = t;
5885 r->parent = t;
5886 t->parent = s;
5887 if (s)
5888 {
5889 if (s->left == p)
5890 s->left = t;
5891 else
5892 s->right = t;
5893 }
5894 else
5895 constructor_pending_elts = t;
5896 }
5897 break;
5898 }
5899 else
5900 {
5901 /* p->balance == -1; growth of right side balances the node. */
5902 p->balance = 0;
5903 break;
5904 }
5905 }
5906
5907 r = p;
5908 p = p->parent;
5909 }
5910}
5911
5912/* Build AVL tree from a sorted chain. */
5913
5914static void
5915set_nonincremental_init (void)
5916{
5917 unsigned HOST_WIDE_INT ix;
5918 tree index, value;
5919
5920 if (TREE_CODE (constructor_type) != RECORD_TYPE
5921 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5922 return;
5923
5924 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value)
5925 add_pending_init (index, value);
5926 constructor_elements = 0;
5927 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5928 {
5929 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5930 /* Skip any nameless bit fields at the beginning. */
5931 while (constructor_unfilled_fields != 0
5932 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5933 && DECL_NAME (constructor_unfilled_fields) == 0)
5934 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5935
5936 }
5937 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5938 {
5939 if (TYPE_DOMAIN (constructor_type))
5940 constructor_unfilled_index
5941 = convert (bitsizetype,
5942 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5943 else
5944 constructor_unfilled_index = bitsize_zero_node;
5945 }
5946 constructor_incremental = 0;
5947}
5948
5949/* Build AVL tree from a string constant. */
5950
5951static void
5952set_nonincremental_init_from_string (tree str)
5953{
5954 tree value, purpose, type;
5955 HOST_WIDE_INT val[2];
5956 const char *p, *end;
5957 int byte, wchar_bytes, charwidth, bitpos;
5958
5959 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5960
5961 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5962 == TYPE_PRECISION (char_type_node))
5963 wchar_bytes = 1;
5964 else
5965 {
5966 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5967 == TYPE_PRECISION (wchar_type_node));
5968 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5969 }
5970 charwidth = TYPE_PRECISION (char_type_node);
5971 type = TREE_TYPE (constructor_type);
5972 p = TREE_STRING_POINTER (str);
5973 end = p + TREE_STRING_LENGTH (str);
5974
5975 for (purpose = bitsize_zero_node;
5976 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5977 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5978 {
5979 if (wchar_bytes == 1)
5980 {
5981 val[1] = (unsigned char) *p++;
5982 val[0] = 0;
5983 }
5984 else
5985 {
5986 val[0] = 0;
5987 val[1] = 0;
5988 for (byte = 0; byte < wchar_bytes; byte++)
5989 {
5990 if (BYTES_BIG_ENDIAN)
5991 bitpos = (wchar_bytes - byte - 1) * charwidth;
5992 else
5993 bitpos = byte * charwidth;
5994 val[bitpos < HOST_BITS_PER_WIDE_INT]
5995 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5996 << (bitpos % HOST_BITS_PER_WIDE_INT);
5997 }
5998 }
5999
6000 if (!TYPE_UNSIGNED (type))
6001 {
6002 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
6003 if (bitpos < HOST_BITS_PER_WIDE_INT)
6004 {
6005 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
6006 {
6007 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
6008 val[0] = -1;
6009 }
6010 }
6011 else if (bitpos == HOST_BITS_PER_WIDE_INT)
6012 {
6013 if (val[1] < 0)
6014 val[0] = -1;
6015 }
6016 else if (val[0] & (((HOST_WIDE_INT) 1)
6017 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
6018 val[0] |= ((HOST_WIDE_INT) -1)
6019 << (bitpos - HOST_BITS_PER_WIDE_INT);
6020 }
6021
6022 value = build_int_cst_wide (type, val[1], val[0]);
6023 add_pending_init (purpose, value);
6024 }
6025
6026 constructor_incremental = 0;
6027}
6028
6029/* Return value of FIELD in pending initializer or zero if the field was
6030 not initialized yet. */
6031
6032static tree
6033find_init_member (tree field)
6034{
6035 struct init_node *p;
6036
6037 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6038 {
6039 if (constructor_incremental
6040 && tree_int_cst_lt (field, constructor_unfilled_index))
6041 set_nonincremental_init ();
6042
6043 p = constructor_pending_elts;
6044 while (p)
6045 {
6046 if (tree_int_cst_lt (field, p->purpose))
6047 p = p->left;
6048 else if (tree_int_cst_lt (p->purpose, field))
6049 p = p->right;
6050 else
6051 return p->value;
6052 }
6053 }
6054 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6055 {
6056 tree bitpos = bit_position (field);
6057
6058 if (constructor_incremental
6059 && (!constructor_unfilled_fields
6060 || tree_int_cst_lt (bitpos,
6061 bit_position (constructor_unfilled_fields))))
6062 set_nonincremental_init ();
6063
6064 p = constructor_pending_elts;
6065 while (p)
6066 {
6067 if (field == p->purpose)
6068 return p->value;
6069 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
6070 p = p->left;
6071 else
6072 p = p->right;
6073 }
6074 }
6075 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6076 {
6077 if (!VEC_empty (constructor_elt, constructor_elements)
6078 && (VEC_last (constructor_elt, constructor_elements)->index
6079 == field))
6080 return VEC_last (constructor_elt, constructor_elements)->value;
6081 }
6082 return 0;
6083}
6084
6085/* "Output" the next constructor element.
6086 At top level, really output it to assembler code now.
6087 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6088 TYPE is the data type that the containing data type wants here.
6089 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6090 If VALUE is a string constant, STRICT_STRING is true if it is
6091 unparenthesized or we should not warn here for it being parenthesized.
6092 For other types of VALUE, STRICT_STRING is not used.
6093
6094 PENDING if non-nil means output pending elements that belong
6095 right after this element. (PENDING is normally 1;
6096 it is 0 while outputting pending elements, to avoid recursion.) */
6097
6098static void
6099output_init_element (tree value, bool strict_string, tree type, tree field,
6100 int pending)
6101{
6102 constructor_elt *celt;
6103
6104 if (type == error_mark_node || value == error_mark_node)
6105 {
6106 constructor_erroneous = 1;
6107 return;
6108 }
6109 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
6110 && (TREE_CODE (value) == STRING_CST
6111 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
6112 && !(TREE_CODE (value) == STRING_CST
6113 && TREE_CODE (type) == ARRAY_TYPE
6114 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
6115 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
6116 TYPE_MAIN_VARIANT (type)))
6117 value = array_to_pointer_conversion (value);
6118
6119 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
6120 && require_constant_value && !flag_isoc99 && pending)
6121 {
6122 /* As an extension, allow initializing objects with static storage
6123 duration with compound literals (which are then treated just as
6124 the brace enclosed list they contain). */
6125 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
6126 value = DECL_INITIAL (decl);
6127 }
6128
6129 if (value == error_mark_node)
6130 constructor_erroneous = 1;
6131 else if (!TREE_CONSTANT (value))
6132 constructor_constant = 0;
6133 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
6134 || ((TREE_CODE (constructor_type) == RECORD_TYPE
6135 || TREE_CODE (constructor_type) == UNION_TYPE)
6136 && DECL_C_BIT_FIELD (field)
6137 && TREE_CODE (value) != INTEGER_CST))
6138 constructor_simple = 0;
6139
6140 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
6141 {
6142 if (require_constant_value)
6143 {
6144 error_init ("initializer element is not constant");
6145 value = error_mark_node;
6146 }
6147 else if (require_constant_elements)
6148 pedwarn ("initializer element is not computable at load time");
6149 }
6150
6151 /* If this field is empty (and not at the end of structure),
6152 don't do anything other than checking the initializer. */
6153 if (field
6154 && (TREE_TYPE (field) == error_mark_node
6155 || (COMPLETE_TYPE_P (TREE_TYPE (field))
6156 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
6157 && (TREE_CODE (constructor_type) == ARRAY_TYPE
6158 || TREE_CHAIN (field)))))
6159 return;
6160
6161 value = digest_init (type, value, strict_string, require_constant_value);
6162 if (value == error_mark_node)
6163 {
6164 constructor_erroneous = 1;
6165 return;
6166 }
6167
6168 /* If this element doesn't come next in sequence,
6169 put it on constructor_pending_elts. */
6170 if (TREE_CODE (constructor_type) == ARRAY_TYPE
6171 && (!constructor_incremental
6172 || !tree_int_cst_equal (field, constructor_unfilled_index)))
6173 {
6174 if (constructor_incremental
6175 && tree_int_cst_lt (field, constructor_unfilled_index))
6176 set_nonincremental_init ();
6177
6178 add_pending_init (field, value);
6179 return;
6180 }
6181 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6182 && (!constructor_incremental
6183 || field != constructor_unfilled_fields))
6184 {
6185 /* We do this for records but not for unions. In a union,
6186 no matter which field is specified, it can be initialized
6187 right away since it starts at the beginning of the union. */
6188 if (constructor_incremental)
6189 {
6190 if (!constructor_unfilled_fields)
6191 set_nonincremental_init ();
6192 else
6193 {
6194 tree bitpos, unfillpos;
6195
6196 bitpos = bit_position (field);
6197 unfillpos = bit_position (constructor_unfilled_fields);
6198
6199 if (tree_int_cst_lt (bitpos, unfillpos))
6200 set_nonincremental_init ();
6201 }
6202 }
6203
6204 add_pending_init (field, value);
6205 return;
6206 }
6207 else if (TREE_CODE (constructor_type) == UNION_TYPE
6208 && !VEC_empty (constructor_elt, constructor_elements))
6209 {
6210 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt,
6211 constructor_elements)->value))
6212 warning_init ("initialized field with side-effects overwritten");
6213 else if (warn_override_init)
6214 warning_init ("initialized field overwritten");
6215
6216 /* We can have just one union field set. */
6217 constructor_elements = 0;
6218 }
6219
6220 /* Otherwise, output this element either to
6221 constructor_elements or to the assembler file. */
6222
6223 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL);
6224 celt->index = field;
6225 celt->value = value;
6226
6227 /* Advance the variable that indicates sequential elements output. */
6228 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6229 constructor_unfilled_index
6230 = size_binop (PLUS_EXPR, constructor_unfilled_index,
6231 bitsize_one_node);
6232 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6233 {
6234 constructor_unfilled_fields
6235 = TREE_CHAIN (constructor_unfilled_fields);
6236
6237 /* Skip any nameless bit fields. */
6238 while (constructor_unfilled_fields != 0
6239 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6240 && DECL_NAME (constructor_unfilled_fields) == 0)
6241 constructor_unfilled_fields =
6242 TREE_CHAIN (constructor_unfilled_fields);
6243 }
6244 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6245 constructor_unfilled_fields = 0;
6246
6247 /* Now output any pending elements which have become next. */
6248 if (pending)
6249 output_pending_init_elements (0);
6250}
6251
6252/* Output any pending elements which have become next.
6253 As we output elements, constructor_unfilled_{fields,index}
6254 advances, which may cause other elements to become next;
6255 if so, they too are output.
6256
6257 If ALL is 0, we return when there are
6258 no more pending elements to output now.
6259
6260 If ALL is 1, we output space as necessary so that
6261 we can output all the pending elements. */
6262
6263static void
6264output_pending_init_elements (int all)
6265{
6266 struct init_node *elt = constructor_pending_elts;
6267 tree next;
6268
6269 retry:
6270
6271 /* Look through the whole pending tree.
6272 If we find an element that should be output now,
6273 output it. Otherwise, set NEXT to the element
6274 that comes first among those still pending. */
6275
6276 next = 0;
6277 while (elt)
6278 {
6279 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6280 {
6281 if (tree_int_cst_equal (elt->purpose,
6282 constructor_unfilled_index))
6283 output_init_element (elt->value, true,
6284 TREE_TYPE (constructor_type),
6285 constructor_unfilled_index, 0);
6286 else if (tree_int_cst_lt (constructor_unfilled_index,
6287 elt->purpose))
6288 {
6289 /* Advance to the next smaller node. */
6290 if (elt->left)
6291 elt = elt->left;
6292 else
6293 {
6294 /* We have reached the smallest node bigger than the
6295 current unfilled index. Fill the space first. */
6296 next = elt->purpose;
6297 break;
6298 }
6299 }
6300 else
6301 {
6302 /* Advance to the next bigger node. */
6303 if (elt->right)
6304 elt = elt->right;
6305 else
6306 {
6307 /* We have reached the biggest node in a subtree. Find
6308 the parent of it, which is the next bigger node. */
6309 while (elt->parent && elt->parent->right == elt)
6310 elt = elt->parent;
6311 elt = elt->parent;
6312 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6313 elt->purpose))
6314 {
6315 next = elt->purpose;
6316 break;
6317 }
6318 }
6319 }
6320 }
6321 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6322 || TREE_CODE (constructor_type) == UNION_TYPE)
6323 {
6324 tree ctor_unfilled_bitpos, elt_bitpos;
6325
6326 /* If the current record is complete we are done. */
6327 if (constructor_unfilled_fields == 0)
6328 break;
6329
6330 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
6331 elt_bitpos = bit_position (elt->purpose);
6332 /* We can't compare fields here because there might be empty
6333 fields in between. */
6334 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6335 {
6336 constructor_unfilled_fields = elt->purpose;
6337 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6338 elt->purpose, 0);
6339 }
6340 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6341 {
6342 /* Advance to the next smaller node. */
6343 if (elt->left)
6344 elt = elt->left;
6345 else
6346 {
6347 /* We have reached the smallest node bigger than the
6348 current unfilled field. Fill the space first. */
6349 next = elt->purpose;
6350 break;
6351 }
6352 }
6353 else
6354 {
6355 /* Advance to the next bigger node. */
6356 if (elt->right)
6357 elt = elt->right;
6358 else
6359 {
6360 /* We have reached the biggest node in a subtree. Find
6361 the parent of it, which is the next bigger node. */
6362 while (elt->parent && elt->parent->right == elt)
6363 elt = elt->parent;
6364 elt = elt->parent;
6365 if (elt
6366 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6367 bit_position (elt->purpose))))
6368 {
6369 next = elt->purpose;
6370 break;
6371 }
6372 }
6373 }
6374 }
6375 }
6376
6377 /* Ordinarily return, but not if we want to output all
6378 and there are elements left. */
6379 if (!(all && next != 0))
6380 return;
6381
6382 /* If it's not incremental, just skip over the gap, so that after
6383 jumping to retry we will output the next successive element. */
6384 if (TREE_CODE (constructor_type) == RECORD_TYPE
6385 || TREE_CODE (constructor_type) == UNION_TYPE)
6386 constructor_unfilled_fields = next;
6387 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6388 constructor_unfilled_index = next;
6389
6390 /* ELT now points to the node in the pending tree with the next
6391 initializer to output. */
6392 goto retry;
6393}
6394
6395/* Add one non-braced element to the current constructor level.
6396 This adjusts the current position within the constructor's type.
6397 This may also start or terminate implicit levels
6398 to handle a partly-braced initializer.
6399
6400 Once this has found the correct level for the new element,
6401 it calls output_init_element. */
6402
6403void
6404process_init_element (struct c_expr value)
6405{
6406 tree orig_value = value.value;
6407 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6408 bool strict_string = value.original_code == STRING_CST;
6409
6410 designator_depth = 0;
6411 designator_erroneous = 0;
6412
6413 /* Handle superfluous braces around string cst as in
6414 char x[] = {"foo"}; */
6415 if (string_flag
6416 && constructor_type
6417 && TREE_CODE (constructor_type) == ARRAY_TYPE
6418 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6419 && integer_zerop (constructor_unfilled_index))
6420 {
6421 if (constructor_stack->replacement_value.value)
6422 error_init ("excess elements in char array initializer");
6423 constructor_stack->replacement_value = value;
6424 return;
6425 }
6426
6427 if (constructor_stack->replacement_value.value != 0)
6428 {
6429 error_init ("excess elements in struct initializer");
6430 return;
6431 }
6432
6433 /* Ignore elements of a brace group if it is entirely superfluous
6434 and has already been diagnosed. */
6435 if (constructor_type == 0)
6436 return;
6437
6438 /* If we've exhausted any levels that didn't have braces,
6439 pop them now. */
6440 while (constructor_stack->implicit)
6441 {
6442 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6443 || TREE_CODE (constructor_type) == UNION_TYPE)
6444 && constructor_fields == 0)
6445 process_init_element (pop_init_level (1));
6446 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6447 && (constructor_max_index == 0
6448 || tree_int_cst_lt (constructor_max_index,
6449 constructor_index)))
6450 process_init_element (pop_init_level (1));
6451 else
6452 break;
6453 }
6454
6455 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6456 if (constructor_range_stack)
6457 {
6458 /* If value is a compound literal and we'll be just using its
6459 content, don't put it into a SAVE_EXPR. */
6460 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6461 || !require_constant_value
6462 || flag_isoc99)
6463 value.value = save_expr (value.value);
6464 }
6465
6466 while (1)
6467 {
6468 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6469 {
6470 tree fieldtype;
6471 enum tree_code fieldcode;
6472
6473 if (constructor_fields == 0)
6474 {
6475 pedwarn_init ("excess elements in struct initializer");
6476 break;
6477 }
6478
6479 fieldtype = TREE_TYPE (constructor_fields);
6480 if (fieldtype != error_mark_node)
6481 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6482 fieldcode = TREE_CODE (fieldtype);
6483
6484 /* Error for non-static initialization of a flexible array member. */
6485 if (fieldcode == ARRAY_TYPE
6486 && !require_constant_value
6487 && TYPE_SIZE (fieldtype) == NULL_TREE
6488 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6489 {
6490 error_init ("non-static initialization of a flexible array member");
6491 break;
6492 }
6493
6494 /* Accept a string constant to initialize a subarray. */
6495 if (value.value != 0
6496 && fieldcode == ARRAY_TYPE
6497 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6498 && string_flag)
6499 value.value = orig_value;
6500 /* Otherwise, if we have come to a subaggregate,
6501 and we don't have an element of its type, push into it. */
6502 else if (value.value != 0
6503 && value.value != error_mark_node
6504 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6505 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6506 || fieldcode == UNION_TYPE))
6507 {
6508 push_init_level (1);
6509 continue;
6510 }
6511
6512 if (value.value)
6513 {
6514 push_member_name (constructor_fields);
6515 output_init_element (value.value, strict_string,
6516 fieldtype, constructor_fields, 1);
6517 RESTORE_SPELLING_DEPTH (constructor_depth);
6518 }
6519 else
6520 /* Do the bookkeeping for an element that was
6521 directly output as a constructor. */
6522 {
6523 /* For a record, keep track of end position of last field. */
6524 if (DECL_SIZE (constructor_fields))
6525 constructor_bit_index
6526 = size_binop (PLUS_EXPR,
6527 bit_position (constructor_fields),
6528 DECL_SIZE (constructor_fields));
6529
6530 /* If the current field was the first one not yet written out,
6531 it isn't now, so update. */
6532 if (constructor_unfilled_fields == constructor_fields)
6533 {
6534 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6535 /* Skip any nameless bit fields. */
6536 while (constructor_unfilled_fields != 0
6537 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6538 && DECL_NAME (constructor_unfilled_fields) == 0)
6539 constructor_unfilled_fields =
6540 TREE_CHAIN (constructor_unfilled_fields);
6541 }
6542 }
6543
6544 constructor_fields = TREE_CHAIN (constructor_fields);
6545 /* Skip any nameless bit fields at the beginning. */
6546 while (constructor_fields != 0
6547 && DECL_C_BIT_FIELD (constructor_fields)
6548 && DECL_NAME (constructor_fields) == 0)
6549 constructor_fields = TREE_CHAIN (constructor_fields);
6550 }
6551 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6552 {
6553 tree fieldtype;
6554 enum tree_code fieldcode;
6555
6556 if (constructor_fields == 0)
6557 {
6558 pedwarn_init ("excess elements in union initializer");
6559 break;
6560 }
6561
6562 fieldtype = TREE_TYPE (constructor_fields);
6563 if (fieldtype != error_mark_node)
6564 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6565 fieldcode = TREE_CODE (fieldtype);
6566
6567 /* Warn that traditional C rejects initialization of unions.
6568 We skip the warning if the value is zero. This is done
6569 under the assumption that the zero initializer in user
6570 code appears conditioned on e.g. __STDC__ to avoid
6571 "missing initializer" warnings and relies on default
6572 initialization to zero in the traditional C case.
6573 We also skip the warning if the initializer is designated,
6574 again on the assumption that this must be conditional on
6575 __STDC__ anyway (and we've already complained about the
6576 member-designator already). */
6577 if (!in_system_header && !constructor_designated
6578 && !(value.value && (integer_zerop (value.value)
6579 || real_zerop (value.value))))
6580 warning (OPT_Wtraditional, "traditional C rejects initialization "
6581 "of unions");
6582
6583 /* Accept a string constant to initialize a subarray. */
6584 if (value.value != 0
6585 && fieldcode == ARRAY_TYPE
6586 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6587 && string_flag)
6588 value.value = orig_value;
6589 /* Otherwise, if we have come to a subaggregate,
6590 and we don't have an element of its type, push into it. */
6591 else if (value.value != 0
6592 && value.value != error_mark_node
6593 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6594 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6595 || fieldcode == UNION_TYPE))
6596 {
6597 push_init_level (1);
6598 continue;
6599 }
6600
6601 if (value.value)
6602 {
6603 push_member_name (constructor_fields);
6604 output_init_element (value.value, strict_string,
6605 fieldtype, constructor_fields, 1);
6606 RESTORE_SPELLING_DEPTH (constructor_depth);
6607 }
6608 else
6609 /* Do the bookkeeping for an element that was
6610 directly output as a constructor. */
6611 {
6612 constructor_bit_index = DECL_SIZE (constructor_fields);
6613 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6614 }
6615
6616 constructor_fields = 0;
6617 }
6618 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6619 {
6620 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6621 enum tree_code eltcode = TREE_CODE (elttype);
6622
6623 /* Accept a string constant to initialize a subarray. */
6624 if (value.value != 0
6625 && eltcode == ARRAY_TYPE
6626 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6627 && string_flag)
6628 value.value = orig_value;
6629 /* Otherwise, if we have come to a subaggregate,
6630 and we don't have an element of its type, push into it. */
6631 else if (value.value != 0
6632 && value.value != error_mark_node
6633 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6634 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6635 || eltcode == UNION_TYPE))
6636 {
6637 push_init_level (1);
6638 continue;
6639 }
6640
6641 if (constructor_max_index != 0
6642 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6643 || integer_all_onesp (constructor_max_index)))
6644 {
6645 pedwarn_init ("excess elements in array initializer");
6646 break;
6647 }
6648
6649 /* Now output the actual element. */
6650 if (value.value)
6651 {
6652 push_array_bounds (tree_low_cst (constructor_index, 1));
6653 output_init_element (value.value, strict_string,
6654 elttype, constructor_index, 1);
6655 RESTORE_SPELLING_DEPTH (constructor_depth);
6656 }
6657
6658 constructor_index
6659 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6660
6661 if (!value.value)
6662 /* If we are doing the bookkeeping for an element that was
6663 directly output as a constructor, we must update
6664 constructor_unfilled_index. */
6665 constructor_unfilled_index = constructor_index;
6666 }
6667 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6668 {
6669 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6670
6671 /* Do a basic check of initializer size. Note that vectors
6672 always have a fixed size derived from their type. */
6673 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6674 {
6675 pedwarn_init ("excess elements in vector initializer");
6676 break;
6677 }
6678
6679 /* Now output the actual element. */
6680 if (value.value)
6681 output_init_element (value.value, strict_string,
6682 elttype, constructor_index, 1);
6683
6684 constructor_index
6685 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6686
6687 if (!value.value)
6688 /* If we are doing the bookkeeping for an element that was
6689 directly output as a constructor, we must update
6690 constructor_unfilled_index. */
6691 constructor_unfilled_index = constructor_index;
6692 }
6693
6694 /* Handle the sole element allowed in a braced initializer
6695 for a scalar variable. */
6696 else if (constructor_type != error_mark_node
6697 && constructor_fields == 0)
6698 {
6699 pedwarn_init ("excess elements in scalar initializer");
6700 break;
6701 }
6702 else
6703 {
6704 if (value.value)
6705 output_init_element (value.value, strict_string,
6706 constructor_type, NULL_TREE, 1);
6707 constructor_fields = 0;
6708 }
6709
6710 /* Handle range initializers either at this level or anywhere higher
6711 in the designator stack. */
6712 if (constructor_range_stack)
6713 {
6714 struct constructor_range_stack *p, *range_stack;
6715 int finish = 0;
6716
6717 range_stack = constructor_range_stack;
6718 constructor_range_stack = 0;
6719 while (constructor_stack != range_stack->stack)
6720 {
6721 gcc_assert (constructor_stack->implicit);
6722 process_init_element (pop_init_level (1));
6723 }
6724 for (p = range_stack;
6725 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6726 p = p->prev)
6727 {
6728 gcc_assert (constructor_stack->implicit);
6729 process_init_element (pop_init_level (1));
6730 }
6731
6732 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6733 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6734 finish = 1;
6735
6736 while (1)
6737 {
6738 constructor_index = p->index;
6739 constructor_fields = p->fields;
6740 if (finish && p->range_end && p->index == p->range_start)
6741 {
6742 finish = 0;
6743 p->prev = 0;
6744 }
6745 p = p->next;
6746 if (!p)
6747 break;
6748 push_init_level (2);
6749 p->stack = constructor_stack;
6750 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6751 p->index = p->range_start;
6752 }
6753
6754 if (!finish)
6755 constructor_range_stack = range_stack;
6756 continue;
6757 }
6758
6759 break;
6760 }
6761
6762 constructor_range_stack = 0;
6763}
6764
6765/* Build a complete asm-statement, whose components are a CV_QUALIFIER
6766 (guaranteed to be 'volatile' or null) and ARGS (represented using
6767 an ASM_EXPR node). */
6768tree
6769build_asm_stmt (tree cv_qualifier, tree args)
6770{
6771 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6772 ASM_VOLATILE_P (args) = 1;
6773 return add_stmt (args);
6774}
6775
6776/* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6777 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6778 SIMPLE indicates whether there was anything at all after the
6779 string in the asm expression -- asm("blah") and asm("blah" : )
6780 are subtly different. We use a ASM_EXPR node to represent this. */
6781tree
6782build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6783 bool simple)
6784{
6785 tree tail;
6786 tree args;
6787 int i;
6788 const char *constraint;
6789 const char **oconstraints;
6790 bool allows_mem, allows_reg, is_inout;
6791 int ninputs, noutputs;
6792
6793 ninputs = list_length (inputs);
6794 noutputs = list_length (outputs);
6795 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6796
6797 string = resolve_asm_operand_names (string, outputs, inputs);
6798
6799 /* Remove output conversions that change the type but not the mode. */
6800 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6801 {
6802 tree output = TREE_VALUE (tail);
6803
6804 /* ??? Really, this should not be here. Users should be using a
6805 proper lvalue, dammit. But there's a long history of using casts
6806 in the output operands. In cases like longlong.h, this becomes a
6807 primitive form of typechecking -- if the cast can be removed, then
6808 the output operand had a type of the proper width; otherwise we'll
6809 get an error. Gross, but ... */
6810 STRIP_NOPS (output);
6811
6812 if (!lvalue_or_else (output, lv_asm))
6813 output = error_mark_node;
6814
6815 if (output != error_mark_node
6816 && (TREE_READONLY (output)
6817 || TYPE_READONLY (TREE_TYPE (output))
6818 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE
6819 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE)
6820 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output)))))
6821 readonly_error (output, lv_asm);
6822
6823 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6824 oconstraints[i] = constraint;
6825
6826 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6827 &allows_mem, &allows_reg, &is_inout))
6828 {
6829 /* If the operand is going to end up in memory,
6830 mark it addressable. */
6831 if (!allows_reg && !c_mark_addressable (output))
6832 output = error_mark_node;
6833 }
6834 else
6835 output = error_mark_node;
6836
6837 TREE_VALUE (tail) = output;
6838 }
6839
6840 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6841 {
6842 tree input;
6843
6844 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6845 input = TREE_VALUE (tail);
6846
6847 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6848 oconstraints, &allows_mem, &allows_reg))
6849 {
6850 /* If the operand is going to end up in memory,
6851 mark it addressable. */
6852 if (!allows_reg && allows_mem)
6853 {
6854 /* Strip the nops as we allow this case. FIXME, this really
6855 should be rejected or made deprecated. */
6856 STRIP_NOPS (input);
6857 if (!c_mark_addressable (input))
6858 input = error_mark_node;
6859 }
6860 }
6861 else
6862 input = error_mark_node;
6863
6864 TREE_VALUE (tail) = input;
6865 }
6866
6867 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6868
6869 /* asm statements without outputs, including simple ones, are treated
6870 as volatile. */
6871 ASM_INPUT_P (args) = simple;
6872 ASM_VOLATILE_P (args) = (noutputs == 0);
6873
6874 return args;
6875}
6876
6877/* Generate a goto statement to LABEL. */
6878
6879tree
6880c_finish_goto_label (tree label)
6881{
6882 tree decl = lookup_label (label);
6883 if (!decl)
6884 return NULL_TREE;
6885
6886 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6887 {
6888 error ("jump into statement expression");
6889 return NULL_TREE;
6890 }
6891
6892 if (C_DECL_UNJUMPABLE_VM (decl))
6893 {
6894 error ("jump into scope of identifier with variably modified type");
6895 return NULL_TREE;
6896 }
6897
6898 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6899 {
6900 /* No jump from outside this statement expression context, so
6901 record that there is a jump from within this context. */
6902 struct c_label_list *nlist;
6903 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6904 nlist->next = label_context_stack_se->labels_used;
6905 nlist->label = decl;
6906 label_context_stack_se->labels_used = nlist;
6907 }
6908
6909 if (!C_DECL_UNDEFINABLE_VM (decl))
6910 {
6911 /* No jump from outside this context context of identifiers with
6912 variably modified type, so record that there is a jump from
6913 within this context. */
6914 struct c_label_list *nlist;
6915 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6916 nlist->next = label_context_stack_vm->labels_used;
6917 nlist->label = decl;
6918 label_context_stack_vm->labels_used = nlist;
6919 }
6920
6921 TREE_USED (decl) = 1;
6922 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6923}
6924
6925/* Generate a computed goto statement to EXPR. */
6926
6927tree
6928c_finish_goto_ptr (tree expr)
6929{
6930 if (pedantic)
6931 pedwarn ("ISO C forbids %<goto *expr;%>");
6932 expr = convert (ptr_type_node, expr);
6933 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6934}
6935
6936/* Generate a C `return' statement. RETVAL is the expression for what
6937 to return, or a null pointer for `return;' with no value. */
6938
6939tree
6940c_finish_return (tree retval)
6941{
6942 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt;
6943 bool no_warning = false;
6944
6945 if (TREE_THIS_VOLATILE (current_function_decl))
6946 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6947
6948 if (!retval)
6949 {
6950 current_function_returns_null = 1;
6951 if ((warn_return_type || flag_isoc99)
6952 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6953 {
6954 pedwarn_c99 ("%<return%> with no value, in "
6955 "function returning non-void");
6956 no_warning = true;
6957 }
6958 }
6959 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6960 {
6961 current_function_returns_null = 1;
6962 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6963 pedwarn ("%<return%> with a value, in function returning void");
6964 }
6965 else
6966 {
6967 tree t = convert_for_assignment (valtype, retval, ic_return,
6968 NULL_TREE, NULL_TREE, 0);
6969 tree res = DECL_RESULT (current_function_decl);
6970 tree inner;
6971
6972 current_function_returns_value = 1;
6973 if (t == error_mark_node)
6974 return NULL_TREE;
6975
6976 inner = t = convert (TREE_TYPE (res), t);
6977
6978 /* Strip any conversions, additions, and subtractions, and see if
6979 we are returning the address of a local variable. Warn if so. */
6980 while (1)
6981 {
6982 switch (TREE_CODE (inner))
6983 {
6984 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6985 case PLUS_EXPR:
6986 inner = TREE_OPERAND (inner, 0);
6987 continue;
6988
6989 case MINUS_EXPR:
6990 /* If the second operand of the MINUS_EXPR has a pointer
6991 type (or is converted from it), this may be valid, so
6992 don't give a warning. */
6993 {
6994 tree op1 = TREE_OPERAND (inner, 1);
6995
6996 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6997 && (TREE_CODE (op1) == NOP_EXPR
6998 || TREE_CODE (op1) == NON_LVALUE_EXPR
6999 || TREE_CODE (op1) == CONVERT_EXPR))
7000 op1 = TREE_OPERAND (op1, 0);
7001
7002 if (POINTER_TYPE_P (TREE_TYPE (op1)))
7003 break;
7004
7005 inner = TREE_OPERAND (inner, 0);
7006 continue;
7007 }
7008
7009 case ADDR_EXPR:
7010 inner = TREE_OPERAND (inner, 0);
7011
7012 while (REFERENCE_CLASS_P (inner)
7013 && TREE_CODE (inner) != INDIRECT_REF)
7014 inner = TREE_OPERAND (inner, 0);
7015
7016 if (DECL_P (inner)
7017 && !DECL_EXTERNAL (inner)
7018 && !TREE_STATIC (inner)
7019 && DECL_CONTEXT (inner) == current_function_decl)
7020 warning (0, "function returns address of local variable");
7021 break;
7022
7023 default:
7024 break;
7025 }
7026
7027 break;
7028 }
7029
7030 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
7031 }
7032
7033 ret_stmt = build_stmt (RETURN_EXPR, retval);
7034 TREE_NO_WARNING (ret_stmt) |= no_warning;
7035 return add_stmt (ret_stmt);
7036}
7037
7038struct c_switch {
7039 /* The SWITCH_EXPR being built. */
7040 tree switch_expr;
7041
7042 /* The original type of the testing expression, i.e. before the
7043 default conversion is applied. */
7044 tree orig_type;
7045
7046 /* A splay-tree mapping the low element of a case range to the high
7047 element, or NULL_TREE if there is no high element. Used to
7048 determine whether or not a new case label duplicates an old case
7049 label. We need a tree, rather than simply a hash table, because
7050 of the GNU case range extension. */
7051 splay_tree cases;
7052
7053 /* Number of nested statement expressions within this switch
7054 statement; if nonzero, case and default labels may not
7055 appear. */
7056 unsigned int blocked_stmt_expr;
7057
7058 /* Scope of outermost declarations of identifiers with variably
7059 modified type within this switch statement; if nonzero, case and
7060 default labels may not appear. */
7061 unsigned int blocked_vm;
7062
7063 /* The next node on the stack. */
7064 struct c_switch *next;
7065};
7066
7067/* A stack of the currently active switch statements. The innermost
7068 switch statement is on the top of the stack. There is no need to
7069 mark the stack for garbage collection because it is only active
7070 during the processing of the body of a function, and we never
7071 collect at that point. */
7072
7073struct c_switch *c_switch_stack;
7074
7075/* Start a C switch statement, testing expression EXP. Return the new
7076 SWITCH_EXPR. */
7077
7078tree
7079c_start_case (tree exp)
7080{
7081 tree orig_type = error_mark_node;
7082 struct c_switch *cs;
7083
7084 if (exp != error_mark_node)
7085 {
7086 orig_type = TREE_TYPE (exp);
7087
7088 if (!INTEGRAL_TYPE_P (orig_type))
7089 {
7090 if (orig_type != error_mark_node)
7091 {
7092 error ("switch quantity not an integer");
7093 orig_type = error_mark_node;
7094 }
7095 exp = integer_zero_node;
7096 }
7097 else
7098 {
7099 tree type = TYPE_MAIN_VARIANT (orig_type);
7100
7101 if (!in_system_header
7102 && (type == long_integer_type_node
7103 || type == long_unsigned_type_node))
7104 warning (OPT_Wtraditional, "%<long%> switch expression not "
7105 "converted to %<int%> in ISO C");
7106
7107 exp = default_conversion (exp);
7108 }
7109 }
7110
7111 /* Add this new SWITCH_EXPR to the stack. */
7112 cs = XNEW (struct c_switch);
7113 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
7114 cs->orig_type = orig_type;
7115 cs->cases = splay_tree_new (case_compare, NULL, NULL);
7116 cs->blocked_stmt_expr = 0;
7117 cs->blocked_vm = 0;
7118 cs->next = c_switch_stack;
7119 c_switch_stack = cs;
7120
7121 return add_stmt (cs->switch_expr);
7122}
7123
7124/* Process a case label. */
7125
7126tree
7127do_case (tree low_value, tree high_value)
7128{
7129 tree label = NULL_TREE;
7130
7131 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
7132 && !c_switch_stack->blocked_vm)
7133 {
7134 label = c_add_case_label (c_switch_stack->cases,
7135 SWITCH_COND (c_switch_stack->switch_expr),
7136 c_switch_stack->orig_type,
7137 low_value, high_value);
7138 if (label == error_mark_node)
7139 label = NULL_TREE;
7140 }
7141 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
7142 {
7143 if (low_value)
7144 error ("case label in statement expression not containing "
7145 "enclosing switch statement");
7146 else
7147 error ("%<default%> label in statement expression not containing "
7148 "enclosing switch statement");
7149 }
7150 else if (c_switch_stack && c_switch_stack->blocked_vm)
7151 {
7152 if (low_value)
7153 error ("case label in scope of identifier with variably modified "
7154 "type not containing enclosing switch statement");
7155 else
7156 error ("%<default%> label in scope of identifier with variably "
7157 "modified type not containing enclosing switch statement");
7158 }
7159 else if (low_value)
7160 error ("case label not within a switch statement");
7161 else
7162 error ("%<default%> label not within a switch statement");
7163
7164 return label;
7165}
7166
7167/* Finish the switch statement. */
7168
7169void
7170c_finish_case (tree body)
7171{
7172 struct c_switch *cs = c_switch_stack;
7173 location_t switch_location;
7174
7175 SWITCH_BODY (cs->switch_expr) = body;
7176
7177 /* We must not be within a statement expression nested in the switch
7178 at this point; we might, however, be within the scope of an
7179 identifier with variably modified type nested in the switch. */
7180 gcc_assert (!cs->blocked_stmt_expr);
7181
7182 /* Emit warnings as needed. */
7183 if (EXPR_HAS_LOCATION (cs->switch_expr))
7184 switch_location = EXPR_LOCATION (cs->switch_expr);
7185 else
7186 switch_location = input_location;
7187 c_do_switch_warnings (cs->cases, switch_location,
7188 TREE_TYPE (cs->switch_expr),
7189 SWITCH_COND (cs->switch_expr));
7190
7191 /* Pop the stack. */
7192 c_switch_stack = cs->next;
7193 splay_tree_delete (cs->cases);
7194 XDELETE (cs);
7195}
7196
7197/* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
7198 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
7199 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
7200 statement, and was not surrounded with parenthesis. */
7201
7202void
7203c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
7204 tree else_block, bool nested_if)
7205{
7206 tree stmt;
7207
7208 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
7209 if (warn_parentheses && nested_if && else_block == NULL)
7210 {
7211 tree inner_if = then_block;
7212
7213 /* We know from the grammar productions that there is an IF nested
7214 within THEN_BLOCK. Due to labels and c99 conditional declarations,
7215 it might not be exactly THEN_BLOCK, but should be the last
7216 non-container statement within. */
7217 while (1)
7218 switch (TREE_CODE (inner_if))
7219 {
7220 case COND_EXPR:
7221 goto found;
7222 case BIND_EXPR:
7223 inner_if = BIND_EXPR_BODY (inner_if);
7224 break;
7225 case STATEMENT_LIST:
7226 inner_if = expr_last (then_block);
7227 break;
7228 case TRY_FINALLY_EXPR:
7229 case TRY_CATCH_EXPR:
7230 inner_if = TREE_OPERAND (inner_if, 0);
7231 break;
7232 default:
7233 gcc_unreachable ();
7234 }
7235 found:
7236
7237 if (COND_EXPR_ELSE (inner_if))
7238 warning (OPT_Wparentheses,
7239 "%Hsuggest explicit braces to avoid ambiguous %<else%>",
7240 &if_locus);
7241 }
7242
7243 empty_body_warning (then_block, else_block);
7244
7245 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
7246 SET_EXPR_LOCATION (stmt, if_locus);
7247 add_stmt (stmt);
7248}
7249
7250/* Emit a general-purpose loop construct. START_LOCUS is the location of
7251 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
7252 is false for DO loops. INCR is the FOR increment expression. BODY is
7253 the statement controlled by the loop. BLAB is the break label. CLAB is
7254 the continue label. Everything is allowed to be NULL. */
7255
7256void
7257c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
7258 tree blab, tree clab, bool cond_is_first)
7259{
7260 tree entry = NULL, exit = NULL, t;
7261
7262 /* If the condition is zero don't generate a loop construct. */
7263 if (cond && integer_zerop (cond))
7264 {
7265 if (cond_is_first)
7266 {
7267 t = build_and_jump (&blab);
7268 SET_EXPR_LOCATION (t, start_locus);
7269 add_stmt (t);
7270 }
7271 }
7272 else
7273 {
7274 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7275
7276 /* If we have an exit condition, then we build an IF with gotos either
7277 out of the loop, or to the top of it. If there's no exit condition,
7278 then we just build a jump back to the top. */
7279 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
7280
7281 if (cond && !integer_nonzerop (cond))
7282 {
7283 /* Canonicalize the loop condition to the end. This means
7284 generating a branch to the loop condition. Reuse the
7285 continue label, if possible. */
7286 if (cond_is_first)
7287 {
7288 if (incr || !clab)
7289 {
7290 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7291 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
7292 }
7293 else
7294 t = build1 (GOTO_EXPR, void_type_node, clab);
7295 SET_EXPR_LOCATION (t, start_locus);
7296 add_stmt (t);
7297 }
7298
7299 t = build_and_jump (&blab);
7300 exit = fold_build3 (COND_EXPR, void_type_node, cond, exit, t);
7301 if (cond_is_first)
7302 SET_EXPR_LOCATION (exit, start_locus);
7303 else
7304 SET_EXPR_LOCATION (exit, input_location);
7305 }
7306
7307 add_stmt (top);
7308 }
7309
7310 if (body)
7311 add_stmt (body);
7312 if (clab)
7313 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
7314 if (incr)
7315 add_stmt (incr);
7316 if (entry)
7317 add_stmt (entry);
7318 if (exit)
7319 add_stmt (exit);
7320 if (blab)
7321 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7322}
7323
7324tree
7325c_finish_bc_stmt (tree *label_p, bool is_break)
7326{
7327 bool skip;
7328 tree label = *label_p;
7329
7330 /* In switch statements break is sometimes stylistically used after
7331 a return statement. This can lead to spurious warnings about
7332 control reaching the end of a non-void function when it is
7333 inlined. Note that we are calling block_may_fallthru with
7334 language specific tree nodes; this works because
7335 block_may_fallthru returns true when given something it does not
7336 understand. */
7337 skip = !block_may_fallthru (cur_stmt_list);
7338
7339 if (!label)
7340 {
7341 if (!skip)
7342 *label_p = label = create_artificial_label ();
7343 }
7344 else if (TREE_CODE (label) == LABEL_DECL)
7345 ;
7346 else switch (TREE_INT_CST_LOW (label))
7347 {
7348 case 0:
7349 if (is_break)
7350 error ("break statement not within loop or switch");
7351 else
7352 error ("continue statement not within a loop");
7353 return NULL_TREE;
7354
7355 case 1:
7356 gcc_assert (is_break);
7357 error ("break statement used with OpenMP for loop");
7358 return NULL_TREE;
7359
7360 default:
7361 gcc_unreachable ();
7362 }
7363
7364 if (skip)
7365 return NULL_TREE;
7366
7367 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7368}
7369
7370/* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7371
7372static void
7373emit_side_effect_warnings (tree expr)
7374{
7375 if (expr == error_mark_node)
7376 ;
7377 else if (!TREE_SIDE_EFFECTS (expr))
7378 {
7379 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7380 warning (0, "%Hstatement with no effect",
7381 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7382 }
7383 else if (warn_unused_value)
7384 warn_if_unused_value (expr, input_location);
7385}
7386
7387/* Process an expression as if it were a complete statement. Emit
7388 diagnostics, but do not call ADD_STMT. */
7389
7390tree
7391c_process_expr_stmt (tree expr)
7392{
7393 if (!expr)
7394 return NULL_TREE;
7395
7396 if (warn_sequence_point)
7397 verify_sequence_points (expr);
7398
7399 if (TREE_TYPE (expr) != error_mark_node
7400 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7401 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7402 error ("expression statement has incomplete type");
7403
7404 /* If we're not processing a statement expression, warn about unused values.
7405 Warnings for statement expressions will be emitted later, once we figure
7406 out which is the result. */
7407 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7408 && (extra_warnings || warn_unused_value))
7409 emit_side_effect_warnings (expr);
7410
7411 /* If the expression is not of a type to which we cannot assign a line
7412 number, wrap the thing in a no-op NOP_EXPR. */
7413 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7414 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7415
7416 if (EXPR_P (expr))
7417 SET_EXPR_LOCATION (expr, input_location);
7418
7419 return expr;
7420}
7421
7422/* Emit an expression as a statement. */
7423
7424tree
7425c_finish_expr_stmt (tree expr)
7426{
7427 if (expr)
7428 return add_stmt (c_process_expr_stmt (expr));
7429 else
7430 return NULL;
7431}
7432
7433/* Do the opposite and emit a statement as an expression. To begin,
7434 create a new binding level and return it. */
7435
7436tree
7437c_begin_stmt_expr (void)
7438{
7439 tree ret;
7440 struct c_label_context_se *nstack;
7441 struct c_label_list *glist;
7442
7443 /* We must force a BLOCK for this level so that, if it is not expanded
7444 later, there is a way to turn off the entire subtree of blocks that
7445 are contained in it. */
7446 keep_next_level ();
7447 ret = c_begin_compound_stmt (true);
7448 if (c_switch_stack)
7449 {
7450 c_switch_stack->blocked_stmt_expr++;
7451 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7452 }
7453 for (glist = label_context_stack_se->labels_used;
7454 glist != NULL;
7455 glist = glist->next)
7456 {
7457 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7458 }
7459 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7460 nstack->labels_def = NULL;
7461 nstack->labels_used = NULL;
7462 nstack->next = label_context_stack_se;
7463 label_context_stack_se = nstack;
7464
7465 /* Mark the current statement list as belonging to a statement list. */
7466 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7467
7468 return ret;
7469}
7470
7471tree
7472c_finish_stmt_expr (tree body)
7473{
7474 tree last, type, tmp, val;
7475 tree *last_p;
7476 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7477
7478 body = c_end_compound_stmt (body, true);
7479 if (c_switch_stack)
7480 {
7481 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7482 c_switch_stack->blocked_stmt_expr--;
7483 }
7484 /* It is no longer possible to jump to labels defined within this
7485 statement expression. */
7486 for (dlist = label_context_stack_se->labels_def;
7487 dlist != NULL;
7488 dlist = dlist->next)
7489 {
7490 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7491 }
7492 /* It is again possible to define labels with a goto just outside
7493 this statement expression. */
7494 for (glist = label_context_stack_se->next->labels_used;
7495 glist != NULL;
7496 glist = glist->next)
7497 {
7498 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7499 glist_prev = glist;
7500 }
7501 if (glist_prev != NULL)
7502 glist_prev->next = label_context_stack_se->labels_used;
7503 else
7504 label_context_stack_se->next->labels_used
7505 = label_context_stack_se->labels_used;
7506 label_context_stack_se = label_context_stack_se->next;
7507
7508 /* Locate the last statement in BODY. See c_end_compound_stmt
7509 about always returning a BIND_EXPR. */
7510 last_p = &BIND_EXPR_BODY (body);
7511 last = BIND_EXPR_BODY (body);
7512
7513 continue_searching:
7514 if (TREE_CODE (last) == STATEMENT_LIST)
7515 {
7516 tree_stmt_iterator i;
7517
7518 /* This can happen with degenerate cases like ({ }). No value. */
7519 if (!TREE_SIDE_EFFECTS (last))
7520 return body;
7521
7522 /* If we're supposed to generate side effects warnings, process
7523 all of the statements except the last. */
7524 if (extra_warnings || warn_unused_value)
7525 {
7526 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7527 emit_side_effect_warnings (tsi_stmt (i));
7528 }
7529 else
7530 i = tsi_last (last);
7531 last_p = tsi_stmt_ptr (i);
7532 last = *last_p;
7533 }
7534
7535 /* If the end of the list is exception related, then the list was split
7536 by a call to push_cleanup. Continue searching. */
7537 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7538 || TREE_CODE (last) == TRY_CATCH_EXPR)
7539 {
7540 last_p = &TREE_OPERAND (last, 0);
7541 last = *last_p;
7542 goto continue_searching;
7543 }
7544
7545 /* In the case that the BIND_EXPR is not necessary, return the
7546 expression out from inside it. */
7547 if (last == error_mark_node
7548 || (last == BIND_EXPR_BODY (body)
7549 && BIND_EXPR_VARS (body) == NULL))
7550 {
7551 /* Do not warn if the return value of a statement expression is
7552 unused. */
7553 if (EXPR_P (last))
7554 TREE_NO_WARNING (last) = 1;
7555 return last;
7556 }
7557
7558 /* Extract the type of said expression. */
7559 type = TREE_TYPE (last);
7560
7561 /* If we're not returning a value at all, then the BIND_EXPR that
7562 we already have is a fine expression to return. */
7563 if (!type || VOID_TYPE_P (type))
7564 return body;
7565
7566 /* Now that we've located the expression containing the value, it seems
7567 silly to make voidify_wrapper_expr repeat the process. Create a
7568 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7569 tmp = create_tmp_var_raw (type, NULL);
7570
7571 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7572 tree_expr_nonnegative_p giving up immediately. */
7573 val = last;
7574 if (TREE_CODE (val) == NOP_EXPR
7575 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7576 val = TREE_OPERAND (val, 0);
7577
7578 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7579 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7580
7581 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7582}
7583
7584/* Begin the scope of an identifier of variably modified type, scope
7585 number SCOPE. Jumping from outside this scope to inside it is not
7586 permitted. */
7587
7588void
7589c_begin_vm_scope (unsigned int scope)
7590{
7591 struct c_label_context_vm *nstack;
7592 struct c_label_list *glist;
7593
7594 gcc_assert (scope > 0);
7595
7596 /* At file_scope, we don't have to do any processing. */
7597 if (label_context_stack_vm == NULL)
7598 return;
7599
7600 if (c_switch_stack && !c_switch_stack->blocked_vm)
7601 c_switch_stack->blocked_vm = scope;
7602 for (glist = label_context_stack_vm->labels_used;
7603 glist != NULL;
7604 glist = glist->next)
7605 {
7606 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7607 }
7608 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7609 nstack->labels_def = NULL;
7610 nstack->labels_used = NULL;
7611 nstack->scope = scope;
7612 nstack->next = label_context_stack_vm;
7613 label_context_stack_vm = nstack;
7614}
7615
7616/* End a scope which may contain identifiers of variably modified
7617 type, scope number SCOPE. */
7618
7619void
7620c_end_vm_scope (unsigned int scope)
7621{
7622 if (label_context_stack_vm == NULL)
7623 return;
7624 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7625 c_switch_stack->blocked_vm = 0;
7626 /* We may have a number of nested scopes of identifiers with
7627 variably modified type, all at this depth. Pop each in turn. */
7628 while (label_context_stack_vm->scope == scope)
7629 {
7630 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7631
7632 /* It is no longer possible to jump to labels defined within this
7633 scope. */
7634 for (dlist = label_context_stack_vm->labels_def;
7635 dlist != NULL;
7636 dlist = dlist->next)
7637 {
7638 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7639 }
7640 /* It is again possible to define labels with a goto just outside
7641 this scope. */
7642 for (glist = label_context_stack_vm->next->labels_used;
7643 glist != NULL;
7644 glist = glist->next)
7645 {
7646 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7647 glist_prev = glist;
7648 }
7649 if (glist_prev != NULL)
7650 glist_prev->next = label_context_stack_vm->labels_used;
7651 else
7652 label_context_stack_vm->next->labels_used
7653 = label_context_stack_vm->labels_used;
7654 label_context_stack_vm = label_context_stack_vm->next;
7655 }
7656}
7657
7658/* Begin and end compound statements. This is as simple as pushing
7659 and popping new statement lists from the tree. */
7660
7661tree
7662c_begin_compound_stmt (bool do_scope)
7663{
7664 tree stmt = push_stmt_list ();
7665 if (do_scope)
7666 push_scope ();
7667 return stmt;
7668}
7669
7670tree
7671c_end_compound_stmt (tree stmt, bool do_scope)
7672{
7673 tree block = NULL;
7674
7675 if (do_scope)
7676 {
7677 if (c_dialect_objc ())
7678 objc_clear_super_receiver ();
7679 block = pop_scope ();
7680 }
7681
7682 stmt = pop_stmt_list (stmt);
7683 stmt = c_build_bind_expr (block, stmt);
7684
7685 /* If this compound statement is nested immediately inside a statement
7686 expression, then force a BIND_EXPR to be created. Otherwise we'll
7687 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7688 STATEMENT_LISTs merge, and thus we can lose track of what statement
7689 was really last. */
7690 if (cur_stmt_list
7691 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7692 && TREE_CODE (stmt) != BIND_EXPR)
7693 {
7694 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7695 TREE_SIDE_EFFECTS (stmt) = 1;
7696 }
7697
7698 return stmt;
7699}
7700
7701/* Queue a cleanup. CLEANUP is an expression/statement to be executed
7702 when the current scope is exited. EH_ONLY is true when this is not
7703 meant to apply to normal control flow transfer. */
7704
7705void
7706push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7707{
7708 enum tree_code code;
7709 tree stmt, list;
7710 bool stmt_expr;
7711
7712 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7713 stmt = build_stmt (code, NULL, cleanup);
7714 add_stmt (stmt);
7715 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7716 list = push_stmt_list ();
7717 TREE_OPERAND (stmt, 0) = list;
7718 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7719}
7720
7721/* Build a binary-operation expression without default conversions.
7722 CODE is the kind of expression to build.
7723 This function differs from `build' in several ways:
7724 the data type of the result is computed and recorded in it,
7725 warnings are generated if arg data types are invalid,
7726 special handling for addition and subtraction of pointers is known,
7727 and some optimization is done (operations on narrow ints
7728 are done in the narrower type when that gives the same result).
7729 Constant folding is also done before the result is returned.
7730
7731 Note that the operands will never have enumeral types, or function
7732 or array types, because either they will have the default conversions
7733 performed or they have both just been converted to some other type in which
7734 the arithmetic is to be done. */
7735
7736tree
7737build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7738 int convert_p)
7739{
7740 tree type0, type1;
7741 enum tree_code code0, code1;
7742 tree op0, op1;
7743 const char *invalid_op_diag;
7744
7745 /* Expression code to give to the expression when it is built.
7746 Normally this is CODE, which is what the caller asked for,
7747 but in some special cases we change it. */
7748 enum tree_code resultcode = code;
7749
7750 /* Data type in which the computation is to be performed.
7751 In the simplest cases this is the common type of the arguments. */
7752 tree result_type = NULL;
7753
7754 /* Nonzero means operands have already been type-converted
7755 in whatever way is necessary.
7756 Zero means they need to be converted to RESULT_TYPE. */
7757 int converted = 0;
7758
7759 /* Nonzero means create the expression with this type, rather than
7760 RESULT_TYPE. */
7761 tree build_type = 0;
7762
7763 /* Nonzero means after finally constructing the expression
7764 convert it to this type. */
7765 tree final_type = 0;
7766
7767 /* Nonzero if this is an operation like MIN or MAX which can
7768 safely be computed in short if both args are promoted shorts.
7769 Also implies COMMON.
7770 -1 indicates a bitwise operation; this makes a difference
7771 in the exact conditions for when it is safe to do the operation
7772 in a narrower mode. */
7773 int shorten = 0;
7774
7775 /* Nonzero if this is a comparison operation;
7776 if both args are promoted shorts, compare the original shorts.
7777 Also implies COMMON. */
7778 int short_compare = 0;
7779
7780 /* Nonzero if this is a right-shift operation, which can be computed on the
7781 original short and then promoted if the operand is a promoted short. */
7782 int short_shift = 0;
7783
7784 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7785 int common = 0;
7786
7787 /* True means types are compatible as far as ObjC is concerned. */
7788 bool objc_ok;
7789
7790 if (convert_p)
7791 {
7792 op0 = default_conversion (orig_op0);
7793 op1 = default_conversion (orig_op1);
7794 }
7795 else
7796 {
7797 op0 = orig_op0;
7798 op1 = orig_op1;
7799 }
7800
7801 type0 = TREE_TYPE (op0);
7802 type1 = TREE_TYPE (op1);
7803
7804 /* The expression codes of the data types of the arguments tell us
7805 whether the arguments are integers, floating, pointers, etc. */
7806 code0 = TREE_CODE (type0);
7807 code1 = TREE_CODE (type1);
7808
7809 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7810 STRIP_TYPE_NOPS (op0);
7811 STRIP_TYPE_NOPS (op1);
7812
7813 /* If an error was already reported for one of the arguments,
7814 avoid reporting another error. */
7815
7816 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7817 return error_mark_node;
7818
7819 if ((invalid_op_diag
7820 = targetm.invalid_binary_op (code, type0, type1)))
7821 {
7822 error (invalid_op_diag, "");
7823 return error_mark_node;
7824 }
7825
7826 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
7827
7828 switch (code)
7829 {
7830 case PLUS_EXPR:
7831 /* Handle the pointer + int case. */
7832 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7833 return pointer_int_sum (PLUS_EXPR, op0, op1);
7834 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7835 return pointer_int_sum (PLUS_EXPR, op1, op0);
7836 else
7837 common = 1;
7838 break;
7839
7840 case MINUS_EXPR:
7841 /* Subtraction of two similar pointers.
7842 We must subtract them as integers, then divide by object size. */
7843 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7844 && comp_target_types (type0, type1))
7845 return pointer_diff (op0, op1);
7846 /* Handle pointer minus int. Just like pointer plus int. */
7847 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7848 return pointer_int_sum (MINUS_EXPR, op0, op1);
7849 else
7850 common = 1;
7851 break;
7852
7853 case MULT_EXPR:
7854 common = 1;
7855 break;
7856
7857 case TRUNC_DIV_EXPR:
7858 case CEIL_DIV_EXPR:
7859 case FLOOR_DIV_EXPR:
7860 case ROUND_DIV_EXPR:
7861 case EXACT_DIV_EXPR:
7862 /* Floating point division by zero is a legitimate way to obtain
7863 infinities and NaNs. */
7864 if (skip_evaluation == 0 && integer_zerop (op1))
7865 warning (OPT_Wdiv_by_zero, "division by zero");
7866
7867 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7868 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7869 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7870 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7871 {
7872 enum tree_code tcode0 = code0, tcode1 = code1;
7873
7874 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7875 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7876 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7877 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7878
7879 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
7880 resultcode = RDIV_EXPR;
7881 else
7882 /* Although it would be tempting to shorten always here, that
7883 loses on some targets, since the modulo instruction is
7884 undefined if the quotient can't be represented in the
7885 computation mode. We shorten only if unsigned or if
7886 dividing by something we know != -1. */
7887 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7888 || (TREE_CODE (op1) == INTEGER_CST
7889 && !integer_all_onesp (op1)));
7890 common = 1;
7891 }
7892 break;
7893
7894 case BIT_AND_EXPR:
7895 case BIT_IOR_EXPR:
7896 case BIT_XOR_EXPR:
7897 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7898 shorten = -1;
7899 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7900 common = 1;
7901 break;
7902
7903 case TRUNC_MOD_EXPR:
7904 case FLOOR_MOD_EXPR:
7905 if (skip_evaluation == 0 && integer_zerop (op1))
7906 warning (OPT_Wdiv_by_zero, "division by zero");
7907
7908 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7909 {
7910 /* Although it would be tempting to shorten always here, that loses
7911 on some targets, since the modulo instruction is undefined if the
7912 quotient can't be represented in the computation mode. We shorten
7913 only if unsigned or if dividing by something we know != -1. */
7914 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7915 || (TREE_CODE (op1) == INTEGER_CST
7916 && !integer_all_onesp (op1)));
7917 common = 1;
7918 }
7919 break;
7920
7921 case TRUTH_ANDIF_EXPR:
7922 case TRUTH_ORIF_EXPR:
7923 case TRUTH_AND_EXPR:
7924 case TRUTH_OR_EXPR:
7925 case TRUTH_XOR_EXPR:
7926 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7927 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7928 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7929 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7930 {
7931 /* Result of these operations is always an int,
7932 but that does not mean the operands should be
7933 converted to ints! */
7934 result_type = integer_type_node;
7935 op0 = c_common_truthvalue_conversion (op0);
7936 op1 = c_common_truthvalue_conversion (op1);
7937 converted = 1;
7938 }
7939 break;
7940
7941 /* Shift operations: result has same type as first operand;
7942 always convert second operand to int.
7943 Also set SHORT_SHIFT if shifting rightward. */
7944
7945 case RSHIFT_EXPR:
7946 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7947 {
7948 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7949 {
7950 if (tree_int_cst_sgn (op1) < 0)
7951 warning (0, "right shift count is negative");
7952 else
7953 {
7954 if (!integer_zerop (op1))
7955 short_shift = 1;
7956
7957 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7958 warning (0, "right shift count >= width of type");
7959 }
7960 }
7961
7962 /* Use the type of the value to be shifted. */
7963 result_type = type0;
7964 /* Convert the shift-count to an integer, regardless of size
7965 of value being shifted. */
7966 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7967 op1 = convert (integer_type_node, op1);
7968 /* Avoid converting op1 to result_type later. */
7969 converted = 1;
7970 }
7971 break;
7972
7973 case LSHIFT_EXPR:
7974 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7975 {
7976 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7977 {
7978 if (tree_int_cst_sgn (op1) < 0)
7979 warning (0, "left shift count is negative");
7980
7981 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7982 warning (0, "left shift count >= width of type");
7983 }
7984
7985 /* Use the type of the value to be shifted. */
7986 result_type = type0;
7987 /* Convert the shift-count to an integer, regardless of size
7988 of value being shifted. */
7989 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7990 op1 = convert (integer_type_node, op1);
7991 /* Avoid converting op1 to result_type later. */
7992 converted = 1;
7993 }
7994 break;
7995
7996 case EQ_EXPR:
7997 case NE_EXPR:
7998 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
7999 warning (OPT_Wfloat_equal,
8000 "comparing floating point with == or != is unsafe");
8001 /* Result of comparison is always int,
8002 but don't convert the args to int! */
8003 build_type = integer_type_node;
8004 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
8005 || code0 == COMPLEX_TYPE)
8006 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
8007 || code1 == COMPLEX_TYPE))
8008 short_compare = 1;
8009 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8010 {
8011 tree tt0 = TREE_TYPE (type0);
8012 tree tt1 = TREE_TYPE (type1);
8013 /* Anything compares with void *. void * compares with anything.
8014 Otherwise, the targets must be compatible
8015 and both must be object or both incomplete. */
8016 if (comp_target_types (type0, type1))
8017 result_type = common_pointer_type (type0, type1);
8018 else if (VOID_TYPE_P (tt0))
8019 {
8020 /* op0 != orig_op0 detects the case of something
8021 whose value is 0 but which isn't a valid null ptr const. */
8022 if (pedantic && !null_pointer_constant_p (orig_op0)
8023 && TREE_CODE (tt1) == FUNCTION_TYPE)
8024 pedwarn ("ISO C forbids comparison of %<void *%>"
8025 " with function pointer");
8026 }
8027 else if (VOID_TYPE_P (tt1))
8028 {
8029 if (pedantic && !null_pointer_constant_p (orig_op1)
8030 && TREE_CODE (tt0) == FUNCTION_TYPE)
8031 pedwarn ("ISO C forbids comparison of %<void *%>"
8032 " with function pointer");
8033 }
8034 else
8035 /* Avoid warning about the volatile ObjC EH puts on decls. */
8036 if (!objc_ok)
8037 pedwarn ("comparison of distinct pointer types lacks a cast");
8038
8039 if (result_type == NULL_TREE)
8040 result_type = ptr_type_node;
8041 }
8042 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8043 {
8044 if (TREE_CODE (op0) == ADDR_EXPR
8045 && DECL_P (TREE_OPERAND (op0, 0))
8046 && (TREE_CODE (TREE_OPERAND (op0, 0)) == PARM_DECL
8047 || TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL
8048 || !DECL_WEAK (TREE_OPERAND (op0, 0))))
8049 warning (OPT_Waddress, "the address of %qD will never be NULL",
8050 TREE_OPERAND (op0, 0));
8051 result_type = type0;
8052 }
8053 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8054 {
8055 if (TREE_CODE (op1) == ADDR_EXPR
8056 && DECL_P (TREE_OPERAND (op1, 0))
8057 && (TREE_CODE (TREE_OPERAND (op1, 0)) == PARM_DECL
8058 || TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL
8059 || !DECL_WEAK (TREE_OPERAND (op1, 0))))
8060 warning (OPT_Waddress, "the address of %qD will never be NULL",
8061 TREE_OPERAND (op1, 0));
8062 result_type = type1;
8063 }
8064 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8065 {
8066 result_type = type0;
8067 pedwarn ("comparison between pointer and integer");
8068 }
8069 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8070 {
8071 result_type = type1;
8072 pedwarn ("comparison between pointer and integer");
8073 }
8074 break;
8075
8076 case LE_EXPR:
8077 case GE_EXPR:
8078 case LT_EXPR:
8079 case GT_EXPR:
8080 build_type = integer_type_node;
8081 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
8082 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
8083 short_compare = 1;
8084 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8085 {
8086 if (comp_target_types (type0, type1))
8087 {
8088 result_type = common_pointer_type (type0, type1);
8089 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
8090 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
8091 pedwarn ("comparison of complete and incomplete pointers");
8092 else if (pedantic
8093 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
8094 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
8095 }
8096 else
8097 {
8098 result_type = ptr_type_node;
8099 pedwarn ("comparison of distinct pointer types lacks a cast");
8100 }
8101 }
8102 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8103 {
8104 result_type = type0;
8105 if (pedantic || extra_warnings)
8106 pedwarn ("ordered comparison of pointer with integer zero");
8107 }
8108 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8109 {
8110 result_type = type1;
8111 if (pedantic)
8112 pedwarn ("ordered comparison of pointer with integer zero");
8113 }
8114 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8115 {
8116 result_type = type0;
8117 pedwarn ("comparison between pointer and integer");
8118 }
8119 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8120 {
8121 result_type = type1;
8122 pedwarn ("comparison between pointer and integer");
8123 }
8124 break;
8125
8126 default:
8127 gcc_unreachable ();
8128 }
8129
8130 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
8131 return error_mark_node;
8132
8133 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
8134 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
8135 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
8136 TREE_TYPE (type1))))
8137 {
8138 binary_op_error (code, type0, type1);
8139 return error_mark_node;
8140 }
8141
8142 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
8143 || code0 == VECTOR_TYPE)
8144 &&
8145 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
8146 || code1 == VECTOR_TYPE))
8147 {
8148 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
8149
8150 if (shorten || common || short_compare)
8151 result_type = c_common_type (type0, type1);
8152
8153 /* For certain operations (which identify themselves by shorten != 0)
8154 if both args were extended from the same smaller type,
8155 do the arithmetic in that type and then extend.
8156
8157 shorten !=0 and !=1 indicates a bitwise operation.
8158 For them, this optimization is safe only if
8159 both args are zero-extended or both are sign-extended.
8160 Otherwise, we might change the result.
8161 Eg, (short)-1 | (unsigned short)-1 is (int)-1
8162 but calculated in (unsigned short) it would be (unsigned short)-1. */
8163
8164 if (shorten && none_complex)
8165 {
8166 int unsigned0, unsigned1;
8167 tree arg0, arg1;
8168 int uns;
8169 tree type;
8170
8171 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents
8172 excessive narrowing when we call get_narrower below. For
8173 example, suppose that OP0 is of unsigned int extended
8174 from signed char and that RESULT_TYPE is long long int.
8175 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
8176 like
8177
8178 (long long int) (unsigned int) signed_char
8179
8180 which get_narrower would narrow down to
8181
8182 (unsigned int) signed char
8183
8184 If we do not cast OP0 first, get_narrower would return
8185 signed_char, which is inconsistent with the case of the
8186 explicit cast. */
8187 op0 = convert (result_type, op0);
8188 op1 = convert (result_type, op1);
8189
8190 arg0 = get_narrower (op0, &unsigned0);
8191 arg1 = get_narrower (op1, &unsigned1);
8192
8193 /* UNS is 1 if the operation to be done is an unsigned one. */
8194 uns = TYPE_UNSIGNED (result_type);
8195
8196 final_type = result_type;
8197
8198 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
8199 but it *requires* conversion to FINAL_TYPE. */
8200
8201 if ((TYPE_PRECISION (TREE_TYPE (op0))
8202 == TYPE_PRECISION (TREE_TYPE (arg0)))
8203 && TREE_TYPE (op0) != final_type)
8204 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
8205 if ((TYPE_PRECISION (TREE_TYPE (op1))
8206 == TYPE_PRECISION (TREE_TYPE (arg1)))
8207 && TREE_TYPE (op1) != final_type)
8208 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
8209
8210 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
8211
8212 /* For bitwise operations, signedness of nominal type
8213 does not matter. Consider only how operands were extended. */
8214 if (shorten == -1)
8215 uns = unsigned0;
8216
8217 /* Note that in all three cases below we refrain from optimizing
8218 an unsigned operation on sign-extended args.
8219 That would not be valid. */
8220
8221 /* Both args variable: if both extended in same way
8222 from same width, do it in that width.
8223 Do it unsigned if args were zero-extended. */
8224 if ((TYPE_PRECISION (TREE_TYPE (arg0))
8225 < TYPE_PRECISION (result_type))
8226 && (TYPE_PRECISION (TREE_TYPE (arg1))
8227 == TYPE_PRECISION (TREE_TYPE (arg0)))
8228 && unsigned0 == unsigned1
8229 && (unsigned0 || !uns))
8230 result_type
8231 = c_common_signed_or_unsigned_type
8232 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
8233 else if (TREE_CODE (arg0) == INTEGER_CST
8234 && (unsigned1 || !uns)
8235 && (TYPE_PRECISION (TREE_TYPE (arg1))
8236 < TYPE_PRECISION (result_type))
8237 && (type
8238 = c_common_signed_or_unsigned_type (unsigned1,
8239 TREE_TYPE (arg1)),
8240 int_fits_type_p (arg0, type)))
8241 result_type = type;
8242 else if (TREE_CODE (arg1) == INTEGER_CST
8243 && (unsigned0 || !uns)
8244 && (TYPE_PRECISION (TREE_TYPE (arg0))
8245 < TYPE_PRECISION (result_type))
8246 && (type
8247 = c_common_signed_or_unsigned_type (unsigned0,
8248 TREE_TYPE (arg0)),
8249 int_fits_type_p (arg1, type)))
8250 result_type = type;
8251 }
8252
8253 /* Shifts can be shortened if shifting right. */
8254
8255 if (short_shift)
8256 {
8257 int unsigned_arg;
8258 tree arg0 = get_narrower (op0, &unsigned_arg);
8259
8260 final_type = result_type;
8261
8262 if (arg0 == op0 && final_type == TREE_TYPE (op0))
8263 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
8264
8265 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
8266 /* We can shorten only if the shift count is less than the
8267 number of bits in the smaller type size. */
8268 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
8269 /* We cannot drop an unsigned shift after sign-extension. */
8270 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
8271 {
8272 /* Do an unsigned shift if the operand was zero-extended. */
8273 result_type
8274 = c_common_signed_or_unsigned_type (unsigned_arg,
8275 TREE_TYPE (arg0));
8276 /* Convert value-to-be-shifted to that type. */
8277 if (TREE_TYPE (op0) != result_type)
8278 op0 = convert (result_type, op0);
8279 converted = 1;
8280 }
8281 }
8282
8283 /* Comparison operations are shortened too but differently.
8284 They identify themselves by setting short_compare = 1. */
8285
8286 if (short_compare)
8287 {
8288 /* Don't write &op0, etc., because that would prevent op0
8289 from being kept in a register.
8290 Instead, make copies of the our local variables and
8291 pass the copies by reference, then copy them back afterward. */
8292 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
8293 enum tree_code xresultcode = resultcode;
8294 tree val
8295 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
8296
8297 if (val != 0)
8298 return val;
8299
8300 op0 = xop0, op1 = xop1;
8301 converted = 1;
8302 resultcode = xresultcode;
8303
8304 if (warn_sign_compare && skip_evaluation == 0)
8305 {
8306 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
8307 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
8308 int unsignedp0, unsignedp1;
8309 tree primop0 = get_narrower (op0, &unsignedp0);
8310 tree primop1 = get_narrower (op1, &unsignedp1);
8311
8312 xop0 = orig_op0;
8313 xop1 = orig_op1;
8314 STRIP_TYPE_NOPS (xop0);
8315 STRIP_TYPE_NOPS (xop1);
8316
8317 /* Give warnings for comparisons between signed and unsigned
8318 quantities that may fail.
8319
8320 Do the checking based on the original operand trees, so that
8321 casts will be considered, but default promotions won't be.
8322
8323 Do not warn if the comparison is being done in a signed type,
8324 since the signed type will only be chosen if it can represent
8325 all the values of the unsigned type. */
8326 if (!TYPE_UNSIGNED (result_type))
8327 /* OK */;
8328 /* Do not warn if both operands are the same signedness. */
8329 else if (op0_signed == op1_signed)
8330 /* OK */;
8331 else
8332 {
8333 tree sop, uop;
8334 bool ovf;
8335
8336 if (op0_signed)
8337 sop = xop0, uop = xop1;
8338 else
8339 sop = xop1, uop = xop0;
8340
8341 /* Do not warn if the signed quantity is an
8342 unsuffixed integer literal (or some static
8343 constant expression involving such literals or a
8344 conditional expression involving such literals)
8345 and it is non-negative. */
8346 if (tree_expr_nonnegative_warnv_p (sop, &ovf))
8347 /* OK */;
8348 /* Do not warn if the comparison is an equality operation,
8349 the unsigned quantity is an integral constant, and it
8350 would fit in the result if the result were signed. */
8351 else if (TREE_CODE (uop) == INTEGER_CST
8352 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
8353 && int_fits_type_p
8354 (uop, c_common_signed_type (result_type)))
8355 /* OK */;
8356 /* Do not warn if the unsigned quantity is an enumeration
8357 constant and its maximum value would fit in the result
8358 if the result were signed. */
8359 else if (TREE_CODE (uop) == INTEGER_CST
8360 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
8361 && int_fits_type_p
8362 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
8363 c_common_signed_type (result_type)))
8364 /* OK */;
8365 else
8366 warning (0, "comparison between signed and unsigned");
8367 }
8368
8369 /* Warn if two unsigned values are being compared in a size
8370 larger than their original size, and one (and only one) is the
8371 result of a `~' operator. This comparison will always fail.
8372
8373 Also warn if one operand is a constant, and the constant
8374 does not have all bits set that are set in the ~ operand
8375 when it is extended. */
8376
8377 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
8378 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
8379 {
8380 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
8381 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
8382 &unsignedp0);
8383 else
8384 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
8385 &unsignedp1);
8386
8387 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
8388 {
8389 tree primop;
8390 HOST_WIDE_INT constant, mask;
8391 int unsignedp, bits;
8392
8393 if (host_integerp (primop0, 0))
8394 {
8395 primop = primop1;
8396 unsignedp = unsignedp1;
8397 constant = tree_low_cst (primop0, 0);
8398 }
8399 else
8400 {
8401 primop = primop0;
8402 unsignedp = unsignedp0;
8403 constant = tree_low_cst (primop1, 0);
8404 }
8405
8406 bits = TYPE_PRECISION (TREE_TYPE (primop));
8407 if (bits < TYPE_PRECISION (result_type)
8408 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8409 {
8410 mask = (~(HOST_WIDE_INT) 0) << bits;
8411 if ((mask & constant) != mask)
8412 warning (0, "comparison of promoted ~unsigned with constant");
8413 }
8414 }
8415 else if (unsignedp0 && unsignedp1
8416 && (TYPE_PRECISION (TREE_TYPE (primop0))
8417 < TYPE_PRECISION (result_type))
8418 && (TYPE_PRECISION (TREE_TYPE (primop1))
8419 < TYPE_PRECISION (result_type)))
8420 warning (0, "comparison of promoted ~unsigned with unsigned");
8421 }
8422 }
8423 }
8424 }
8425
8426 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8427 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8428 Then the expression will be built.
8429 It will be given type FINAL_TYPE if that is nonzero;
8430 otherwise, it will be given type RESULT_TYPE. */
8431
8432 if (!result_type)
8433 {
8434 binary_op_error (code, TREE_TYPE (op0), TREE_TYPE (op1));
8435 return error_mark_node;
8436 }
8437
8438 if (!converted)
8439 {
8440 if (TREE_TYPE (op0) != result_type)
8441 op0 = convert_and_check (result_type, op0);
8442 if (TREE_TYPE (op1) != result_type)
8443 op1 = convert_and_check (result_type, op1);
8444
8445 /* This can happen if one operand has a vector type, and the other
8446 has a different type. */
8447 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8448 return error_mark_node;
8449 }
8450
8451 if (build_type == NULL_TREE)
8452 build_type = result_type;
8453
8454 {
8455 /* Treat expressions in initializers specially as they can't trap. */
8456 tree result = require_constant_value ? fold_build2_initializer (resultcode,
8457 build_type,
8458 op0, op1)
8459 : fold_build2 (resultcode, build_type,
8460 op0, op1);
8461
8462 if (final_type != 0)
8463 result = convert (final_type, result);
8464 return result;
8465 }
8466}
8467
8468
8469/* Convert EXPR to be a truth-value, validating its type for this
8470 purpose. */
8471
8472tree
8473c_objc_common_truthvalue_conversion (tree expr)
8474{
8475 switch (TREE_CODE (TREE_TYPE (expr)))
8476 {
8477 case ARRAY_TYPE:
8478 error ("used array that cannot be converted to pointer where scalar is required");
8479 return error_mark_node;
8480
8481 case RECORD_TYPE:
8482 error ("used struct type value where scalar is required");
8483 return error_mark_node;
8484
8485 case UNION_TYPE:
8486 error ("used union type value where scalar is required");
8487 return error_mark_node;
8488
8489 case FUNCTION_TYPE:
8490 gcc_unreachable ();
8491
8492 default:
8493 break;
8494 }
8495
8496 /* ??? Should we also give an error for void and vectors rather than
8497 leaving those to give errors later? */
8498 return c_common_truthvalue_conversion (expr);
8499}
8500
8501
8502/* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
8503 required. */
8504
8505tree
8506c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED,
8507 bool *ti ATTRIBUTE_UNUSED, bool *se)
8508{
8509 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR)
8510 {
8511 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr);
8512 /* Executing a compound literal inside a function reinitializes
8513 it. */
8514 if (!TREE_STATIC (decl))
8515 *se = true;
8516 return decl;
8517 }
8518 else
8519 return expr;
8520}
8521
8522/* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
8523
8524tree
8525c_begin_omp_parallel (void)
8526{
8527 tree block;
8528
8529 keep_next_level ();
8530 block = c_begin_compound_stmt (true);
8531
8532 return block;
8533}
8534
8535tree
8536c_finish_omp_parallel (tree clauses, tree block)
8537{
8538 tree stmt;
8539
8540 block = c_end_compound_stmt (block, true);
8541
8542 stmt = make_node (OMP_PARALLEL);
8543 TREE_TYPE (stmt) = void_type_node;
8544 OMP_PARALLEL_CLAUSES (stmt) = clauses;
8545 OMP_PARALLEL_BODY (stmt) = block;
8546
8547 return add_stmt (stmt);
8548}
8549
8550/* For all elements of CLAUSES, validate them vs OpenMP constraints.
8551 Remove any elements from the list that are invalid. */
8552
8553tree
8554c_finish_omp_clauses (tree clauses)
8555{
8556 bitmap_head generic_head, firstprivate_head, lastprivate_head;
8557 tree c, t, *pc = &clauses;
8558 const char *name;
8559
8560 bitmap_obstack_initialize (NULL);
8561 bitmap_initialize (&generic_head, &bitmap_default_obstack);
8562 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack);
8563 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack);
8564
8565 for (pc = &clauses, c = clauses; c ; c = *pc)
8566 {
8567 bool remove = false;
8568 bool need_complete = false;
8569 bool need_implicitly_determined = false;
8570
8571 switch (OMP_CLAUSE_CODE (c))
8572 {
8573 case OMP_CLAUSE_SHARED:
8574 name = "shared";
8575 need_implicitly_determined = true;
8576 goto check_dup_generic;
8577
8578 case OMP_CLAUSE_PRIVATE:
8579 name = "private";
8580 need_complete = true;
8581 need_implicitly_determined = true;
8582 goto check_dup_generic;
8583
8584 case OMP_CLAUSE_REDUCTION:
8585 name = "reduction";
8586 need_implicitly_determined = true;
8587 t = OMP_CLAUSE_DECL (c);
8588 if (AGGREGATE_TYPE_P (TREE_TYPE (t))
8589 || POINTER_TYPE_P (TREE_TYPE (t)))
8590 {
8591 error ("%qE has invalid type for %<reduction%>", t);
8592 remove = true;
8593 }
8594 else if (FLOAT_TYPE_P (TREE_TYPE (t)))
8595 {
8596 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c);
8597 const char *r_name = NULL;
8598
8599 switch (r_code)
8600 {
8601 case PLUS_EXPR:
8602 case MULT_EXPR:
8603 case MINUS_EXPR:
8604 break;
8605 case BIT_AND_EXPR:
8606 r_name = "&";
8607 break;
8608 case BIT_XOR_EXPR:
8609 r_name = "^";
8610 break;
8611 case BIT_IOR_EXPR:
8612 r_name = "|";
8613 break;
8614 case TRUTH_ANDIF_EXPR:
8615 r_name = "&&";
8616 break;
8617 case TRUTH_ORIF_EXPR:
8618 r_name = "||";
8619 break;
8620 default:
8621 gcc_unreachable ();
8622 }
8623 if (r_name)
8624 {
8625 error ("%qE has invalid type for %<reduction(%s)%>",
8626 t, r_name);
8627 remove = true;
8628 }
8629 }
8630 goto check_dup_generic;
8631
8632 case OMP_CLAUSE_COPYPRIVATE:
8633 name = "copyprivate";
8634 goto check_dup_generic;
8635
8636 case OMP_CLAUSE_COPYIN:
8637 name = "copyin";
8638 t = OMP_CLAUSE_DECL (c);
8639 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t))
8640 {
8641 error ("%qE must be %<threadprivate%> for %<copyin%>", t);
8642 remove = true;
8643 }
8644 goto check_dup_generic;
8645
8646 check_dup_generic:
8647 t = OMP_CLAUSE_DECL (c);
8648 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8649 {
8650 error ("%qE is not a variable in clause %qs", t, name);
8651 remove = true;
8652 }
8653 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8654 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))
8655 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8656 {
8657 error ("%qE appears more than once in data clauses", t);
8658 remove = true;
8659 }
8660 else
8661 bitmap_set_bit (&generic_head, DECL_UID (t));
8662 break;
8663
8664 case OMP_CLAUSE_FIRSTPRIVATE:
8665 name = "firstprivate";
8666 t = OMP_CLAUSE_DECL (c);
8667 need_complete = true;
8668 need_implicitly_determined = true;
8669 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8670 {
8671 error ("%qE is not a variable in clause %<firstprivate%>", t);
8672 remove = true;
8673 }
8674 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8675 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
8676 {
8677 error ("%qE appears more than once in data clauses", t);
8678 remove = true;
8679 }
8680 else
8681 bitmap_set_bit (&firstprivate_head, DECL_UID (t));
8682 break;
8683
8684 case OMP_CLAUSE_LASTPRIVATE:
8685 name = "lastprivate";
8686 t = OMP_CLAUSE_DECL (c);
8687 need_complete = true;
8688 need_implicitly_determined = true;
8689 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8690 {
8691 error ("%qE is not a variable in clause %<lastprivate%>", t);
8692 remove = true;
8693 }
8694 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8695 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8696 {
8697 error ("%qE appears more than once in data clauses", t);
8698 remove = true;
8699 }
8700 else
8701 bitmap_set_bit (&lastprivate_head, DECL_UID (t));
8702 break;
8703
8704 case OMP_CLAUSE_IF:
8705 case OMP_CLAUSE_NUM_THREADS:
8706 case OMP_CLAUSE_SCHEDULE:
8707 case OMP_CLAUSE_NOWAIT:
8708 case OMP_CLAUSE_ORDERED:
8709 case OMP_CLAUSE_DEFAULT:
8710 pc = &OMP_CLAUSE_CHAIN (c);
8711 continue;
8712
8713 default:
8714 gcc_unreachable ();
8715 }
8716
8717 if (!remove)
8718 {
8719 t = OMP_CLAUSE_DECL (c);
8720
8721 if (need_complete)
8722 {
8723 t = require_complete_type (t);
8724 if (t == error_mark_node)
8725 remove = true;
8726 }
8727
8728 if (need_implicitly_determined)
8729 {
8730 const char *share_name = NULL;
8731
8732 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t))
8733 share_name = "threadprivate";
8734 else switch (c_omp_predetermined_sharing (t))
8735 {
8736 case OMP_CLAUSE_DEFAULT_UNSPECIFIED:
8737 break;
8738 case OMP_CLAUSE_DEFAULT_SHARED:
8739 share_name = "shared";
8740 break;
8741 case OMP_CLAUSE_DEFAULT_PRIVATE:
8742 share_name = "private";
8743 break;
8744 default:
8745 gcc_unreachable ();
8746 }
8747 if (share_name)
8748 {
8749 error ("%qE is predetermined %qs for %qs",
8750 t, share_name, name);
8751 remove = true;
8752 }
8753 }
8754 }
8755
8756 if (remove)
8757 *pc = OMP_CLAUSE_CHAIN (c);
8758 else
8759 pc = &OMP_CLAUSE_CHAIN (c);
8760 }
8761
8762 bitmap_obstack_release (NULL);
8763 return clauses;
8764}
| 4633 && TREE_CONSTANT (inside_init))
4634 {
4635 if (TREE_CODE (inside_init) == VECTOR_CST
4636 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4637 TYPE_MAIN_VARIANT (type)))
4638 return inside_init;
4639
4640 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4641 {
4642 unsigned HOST_WIDE_INT ix;
4643 tree value;
4644 bool constant_p = true;
4645
4646 /* Iterate through elements and check if all constructor
4647 elements are *_CSTs. */
4648 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value)
4649 if (!CONSTANT_CLASS_P (value))
4650 {
4651 constant_p = false;
4652 break;
4653 }
4654
4655 if (constant_p)
4656 return build_vector_from_ctor (type,
4657 CONSTRUCTOR_ELTS (inside_init));
4658 }
4659 }
4660
4661 /* Any type can be initialized
4662 from an expression of the same type, optionally with braces. */
4663
4664 if (inside_init && TREE_TYPE (inside_init) != 0
4665 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4666 TYPE_MAIN_VARIANT (type))
4667 || (code == ARRAY_TYPE
4668 && comptypes (TREE_TYPE (inside_init), type))
4669 || (code == VECTOR_TYPE
4670 && comptypes (TREE_TYPE (inside_init), type))
4671 || (code == POINTER_TYPE
4672 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4673 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4674 TREE_TYPE (type)))))
4675 {
4676 if (code == POINTER_TYPE)
4677 {
4678 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4679 {
4680 if (TREE_CODE (inside_init) == STRING_CST
4681 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4682 inside_init = array_to_pointer_conversion (inside_init);
4683 else
4684 {
4685 error_init ("invalid use of non-lvalue array");
4686 return error_mark_node;
4687 }
4688 }
4689 }
4690
4691 if (code == VECTOR_TYPE)
4692 /* Although the types are compatible, we may require a
4693 conversion. */
4694 inside_init = convert (type, inside_init);
4695
4696 if (require_constant
4697 && (code == VECTOR_TYPE || !flag_isoc99)
4698 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4699 {
4700 /* As an extension, allow initializing objects with static storage
4701 duration with compound literals (which are then treated just as
4702 the brace enclosed list they contain). Also allow this for
4703 vectors, as we can only assign them with compound literals. */
4704 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4705 inside_init = DECL_INITIAL (decl);
4706 }
4707
4708 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4709 && TREE_CODE (inside_init) != CONSTRUCTOR)
4710 {
4711 error_init ("array initialized from non-constant array expression");
4712 return error_mark_node;
4713 }
4714
4715 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4716 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4717
4718 /* Compound expressions can only occur here if -pedantic or
4719 -pedantic-errors is specified. In the later case, we always want
4720 an error. In the former case, we simply want a warning. */
4721 if (require_constant && pedantic
4722 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4723 {
4724 inside_init
4725 = valid_compound_expr_initializer (inside_init,
4726 TREE_TYPE (inside_init));
4727 if (inside_init == error_mark_node)
4728 error_init ("initializer element is not constant");
4729 else
4730 pedwarn_init ("initializer element is not constant");
4731 if (flag_pedantic_errors)
4732 inside_init = error_mark_node;
4733 }
4734 else if (require_constant
4735 && !initializer_constant_valid_p (inside_init,
4736 TREE_TYPE (inside_init)))
4737 {
4738 error_init ("initializer element is not constant");
4739 inside_init = error_mark_node;
4740 }
4741
4742 /* Added to enable additional -Wmissing-format-attribute warnings. */
4743 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE)
4744 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE,
4745 NULL_TREE, 0);
4746 return inside_init;
4747 }
4748
4749 /* Handle scalar types, including conversions. */
4750
4751 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4752 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4753 || code == VECTOR_TYPE)
4754 {
4755 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
4756 && (TREE_CODE (init) == STRING_CST
4757 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
4758 init = array_to_pointer_conversion (init);
4759 inside_init
4760 = convert_for_assignment (type, init, ic_init,
4761 NULL_TREE, NULL_TREE, 0);
4762
4763 /* Check to see if we have already given an error message. */
4764 if (inside_init == error_mark_node)
4765 ;
4766 else if (require_constant && !TREE_CONSTANT (inside_init))
4767 {
4768 error_init ("initializer element is not constant");
4769 inside_init = error_mark_node;
4770 }
4771 else if (require_constant
4772 && !initializer_constant_valid_p (inside_init,
4773 TREE_TYPE (inside_init)))
4774 {
4775 error_init ("initializer element is not computable at load time");
4776 inside_init = error_mark_node;
4777 }
4778
4779 return inside_init;
4780 }
4781
4782 /* Come here only for records and arrays. */
4783
4784 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4785 {
4786 error_init ("variable-sized object may not be initialized");
4787 return error_mark_node;
4788 }
4789
4790 error_init ("invalid initializer");
4791 return error_mark_node;
4792}
4793
4794/* Handle initializers that use braces. */
4795
4796/* Type of object we are accumulating a constructor for.
4797 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4798static tree constructor_type;
4799
4800/* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4801 left to fill. */
4802static tree constructor_fields;
4803
4804/* For an ARRAY_TYPE, this is the specified index
4805 at which to store the next element we get. */
4806static tree constructor_index;
4807
4808/* For an ARRAY_TYPE, this is the maximum index. */
4809static tree constructor_max_index;
4810
4811/* For a RECORD_TYPE, this is the first field not yet written out. */
4812static tree constructor_unfilled_fields;
4813
4814/* For an ARRAY_TYPE, this is the index of the first element
4815 not yet written out. */
4816static tree constructor_unfilled_index;
4817
4818/* In a RECORD_TYPE, the byte index of the next consecutive field.
4819 This is so we can generate gaps between fields, when appropriate. */
4820static tree constructor_bit_index;
4821
4822/* If we are saving up the elements rather than allocating them,
4823 this is the list of elements so far (in reverse order,
4824 most recent first). */
4825static VEC(constructor_elt,gc) *constructor_elements;
4826
4827/* 1 if constructor should be incrementally stored into a constructor chain,
4828 0 if all the elements should be kept in AVL tree. */
4829static int constructor_incremental;
4830
4831/* 1 if so far this constructor's elements are all compile-time constants. */
4832static int constructor_constant;
4833
4834/* 1 if so far this constructor's elements are all valid address constants. */
4835static int constructor_simple;
4836
4837/* 1 if this constructor is erroneous so far. */
4838static int constructor_erroneous;
4839
4840/* Structure for managing pending initializer elements, organized as an
4841 AVL tree. */
4842
4843struct init_node
4844{
4845 struct init_node *left, *right;
4846 struct init_node *parent;
4847 int balance;
4848 tree purpose;
4849 tree value;
4850};
4851
4852/* Tree of pending elements at this constructor level.
4853 These are elements encountered out of order
4854 which belong at places we haven't reached yet in actually
4855 writing the output.
4856 Will never hold tree nodes across GC runs. */
4857static struct init_node *constructor_pending_elts;
4858
4859/* The SPELLING_DEPTH of this constructor. */
4860static int constructor_depth;
4861
4862/* DECL node for which an initializer is being read.
4863 0 means we are reading a constructor expression
4864 such as (struct foo) {...}. */
4865static tree constructor_decl;
4866
4867/* Nonzero if this is an initializer for a top-level decl. */
4868static int constructor_top_level;
4869
4870/* Nonzero if there were any member designators in this initializer. */
4871static int constructor_designated;
4872
4873/* Nesting depth of designator list. */
4874static int designator_depth;
4875
4876/* Nonzero if there were diagnosed errors in this designator list. */
4877static int designator_erroneous;
4878
4879
4880/* This stack has a level for each implicit or explicit level of
4881 structuring in the initializer, including the outermost one. It
4882 saves the values of most of the variables above. */
4883
4884struct constructor_range_stack;
4885
4886struct constructor_stack
4887{
4888 struct constructor_stack *next;
4889 tree type;
4890 tree fields;
4891 tree index;
4892 tree max_index;
4893 tree unfilled_index;
4894 tree unfilled_fields;
4895 tree bit_index;
4896 VEC(constructor_elt,gc) *elements;
4897 struct init_node *pending_elts;
4898 int offset;
4899 int depth;
4900 /* If value nonzero, this value should replace the entire
4901 constructor at this level. */
4902 struct c_expr replacement_value;
4903 struct constructor_range_stack *range_stack;
4904 char constant;
4905 char simple;
4906 char implicit;
4907 char erroneous;
4908 char outer;
4909 char incremental;
4910 char designated;
4911};
4912
4913static struct constructor_stack *constructor_stack;
4914
4915/* This stack represents designators from some range designator up to
4916 the last designator in the list. */
4917
4918struct constructor_range_stack
4919{
4920 struct constructor_range_stack *next, *prev;
4921 struct constructor_stack *stack;
4922 tree range_start;
4923 tree index;
4924 tree range_end;
4925 tree fields;
4926};
4927
4928static struct constructor_range_stack *constructor_range_stack;
4929
4930/* This stack records separate initializers that are nested.
4931 Nested initializers can't happen in ANSI C, but GNU C allows them
4932 in cases like { ... (struct foo) { ... } ... }. */
4933
4934struct initializer_stack
4935{
4936 struct initializer_stack *next;
4937 tree decl;
4938 struct constructor_stack *constructor_stack;
4939 struct constructor_range_stack *constructor_range_stack;
4940 VEC(constructor_elt,gc) *elements;
4941 struct spelling *spelling;
4942 struct spelling *spelling_base;
4943 int spelling_size;
4944 char top_level;
4945 char require_constant_value;
4946 char require_constant_elements;
4947};
4948
4949static struct initializer_stack *initializer_stack;
4950
4951/* Prepare to parse and output the initializer for variable DECL. */
4952
4953void
4954start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4955{
4956 const char *locus;
4957 struct initializer_stack *p = XNEW (struct initializer_stack);
4958
4959 p->decl = constructor_decl;
4960 p->require_constant_value = require_constant_value;
4961 p->require_constant_elements = require_constant_elements;
4962 p->constructor_stack = constructor_stack;
4963 p->constructor_range_stack = constructor_range_stack;
4964 p->elements = constructor_elements;
4965 p->spelling = spelling;
4966 p->spelling_base = spelling_base;
4967 p->spelling_size = spelling_size;
4968 p->top_level = constructor_top_level;
4969 p->next = initializer_stack;
4970 initializer_stack = p;
4971
4972 constructor_decl = decl;
4973 constructor_designated = 0;
4974 constructor_top_level = top_level;
4975
4976 if (decl != 0 && decl != error_mark_node)
4977 {
4978 require_constant_value = TREE_STATIC (decl);
4979 require_constant_elements
4980 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4981 /* For a scalar, you can always use any value to initialize,
4982 even within braces. */
4983 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4984 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4985 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4986 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4987 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4988 }
4989 else
4990 {
4991 require_constant_value = 0;
4992 require_constant_elements = 0;
4993 locus = "(anonymous)";
4994 }
4995
4996 constructor_stack = 0;
4997 constructor_range_stack = 0;
4998
4999 missing_braces_mentioned = 0;
5000
5001 spelling_base = 0;
5002 spelling_size = 0;
5003 RESTORE_SPELLING_DEPTH (0);
5004
5005 if (locus)
5006 push_string (locus);
5007}
5008
5009void
5010finish_init (void)
5011{
5012 struct initializer_stack *p = initializer_stack;
5013
5014 /* Free the whole constructor stack of this initializer. */
5015 while (constructor_stack)
5016 {
5017 struct constructor_stack *q = constructor_stack;
5018 constructor_stack = q->next;
5019 free (q);
5020 }
5021
5022 gcc_assert (!constructor_range_stack);
5023
5024 /* Pop back to the data of the outer initializer (if any). */
5025 free (spelling_base);
5026
5027 constructor_decl = p->decl;
5028 require_constant_value = p->require_constant_value;
5029 require_constant_elements = p->require_constant_elements;
5030 constructor_stack = p->constructor_stack;
5031 constructor_range_stack = p->constructor_range_stack;
5032 constructor_elements = p->elements;
5033 spelling = p->spelling;
5034 spelling_base = p->spelling_base;
5035 spelling_size = p->spelling_size;
5036 constructor_top_level = p->top_level;
5037 initializer_stack = p->next;
5038 free (p);
5039}
5040
5041/* Call here when we see the initializer is surrounded by braces.
5042 This is instead of a call to push_init_level;
5043 it is matched by a call to pop_init_level.
5044
5045 TYPE is the type to initialize, for a constructor expression.
5046 For an initializer for a decl, TYPE is zero. */
5047
5048void
5049really_start_incremental_init (tree type)
5050{
5051 struct constructor_stack *p = XNEW (struct constructor_stack);
5052
5053 if (type == 0)
5054 type = TREE_TYPE (constructor_decl);
5055
5056 if (targetm.vector_opaque_p (type))
5057 error ("opaque vector types cannot be initialized");
5058
5059 p->type = constructor_type;
5060 p->fields = constructor_fields;
5061 p->index = constructor_index;
5062 p->max_index = constructor_max_index;
5063 p->unfilled_index = constructor_unfilled_index;
5064 p->unfilled_fields = constructor_unfilled_fields;
5065 p->bit_index = constructor_bit_index;
5066 p->elements = constructor_elements;
5067 p->constant = constructor_constant;
5068 p->simple = constructor_simple;
5069 p->erroneous = constructor_erroneous;
5070 p->pending_elts = constructor_pending_elts;
5071 p->depth = constructor_depth;
5072 p->replacement_value.value = 0;
5073 p->replacement_value.original_code = ERROR_MARK;
5074 p->implicit = 0;
5075 p->range_stack = 0;
5076 p->outer = 0;
5077 p->incremental = constructor_incremental;
5078 p->designated = constructor_designated;
5079 p->next = 0;
5080 constructor_stack = p;
5081
5082 constructor_constant = 1;
5083 constructor_simple = 1;
5084 constructor_depth = SPELLING_DEPTH ();
5085 constructor_elements = 0;
5086 constructor_pending_elts = 0;
5087 constructor_type = type;
5088 constructor_incremental = 1;
5089 constructor_designated = 0;
5090 designator_depth = 0;
5091 designator_erroneous = 0;
5092
5093 if (TREE_CODE (constructor_type) == RECORD_TYPE
5094 || TREE_CODE (constructor_type) == UNION_TYPE)
5095 {
5096 constructor_fields = TYPE_FIELDS (constructor_type);
5097 /* Skip any nameless bit fields at the beginning. */
5098 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5099 && DECL_NAME (constructor_fields) == 0)
5100 constructor_fields = TREE_CHAIN (constructor_fields);
5101
5102 constructor_unfilled_fields = constructor_fields;
5103 constructor_bit_index = bitsize_zero_node;
5104 }
5105 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5106 {
5107 if (TYPE_DOMAIN (constructor_type))
5108 {
5109 constructor_max_index
5110 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5111
5112 /* Detect non-empty initializations of zero-length arrays. */
5113 if (constructor_max_index == NULL_TREE
5114 && TYPE_SIZE (constructor_type))
5115 constructor_max_index = build_int_cst (NULL_TREE, -1);
5116
5117 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5118 to initialize VLAs will cause a proper error; avoid tree
5119 checking errors as well by setting a safe value. */
5120 if (constructor_max_index
5121 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5122 constructor_max_index = build_int_cst (NULL_TREE, -1);
5123
5124 constructor_index
5125 = convert (bitsizetype,
5126 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5127 }
5128 else
5129 {
5130 constructor_index = bitsize_zero_node;
5131 constructor_max_index = NULL_TREE;
5132 }
5133
5134 constructor_unfilled_index = constructor_index;
5135 }
5136 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5137 {
5138 /* Vectors are like simple fixed-size arrays. */
5139 constructor_max_index =
5140 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5141 constructor_index = bitsize_zero_node;
5142 constructor_unfilled_index = constructor_index;
5143 }
5144 else
5145 {
5146 /* Handle the case of int x = {5}; */
5147 constructor_fields = constructor_type;
5148 constructor_unfilled_fields = constructor_type;
5149 }
5150}
5151
5152/* Push down into a subobject, for initialization.
5153 If this is for an explicit set of braces, IMPLICIT is 0.
5154 If it is because the next element belongs at a lower level,
5155 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5156
5157void
5158push_init_level (int implicit)
5159{
5160 struct constructor_stack *p;
5161 tree value = NULL_TREE;
5162
5163 /* If we've exhausted any levels that didn't have braces,
5164 pop them now. If implicit == 1, this will have been done in
5165 process_init_element; do not repeat it here because in the case
5166 of excess initializers for an empty aggregate this leads to an
5167 infinite cycle of popping a level and immediately recreating
5168 it. */
5169 if (implicit != 1)
5170 {
5171 while (constructor_stack->implicit)
5172 {
5173 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5174 || TREE_CODE (constructor_type) == UNION_TYPE)
5175 && constructor_fields == 0)
5176 process_init_element (pop_init_level (1));
5177 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5178 && constructor_max_index
5179 && tree_int_cst_lt (constructor_max_index,
5180 constructor_index))
5181 process_init_element (pop_init_level (1));
5182 else
5183 break;
5184 }
5185 }
5186
5187 /* Unless this is an explicit brace, we need to preserve previous
5188 content if any. */
5189 if (implicit)
5190 {
5191 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5192 || TREE_CODE (constructor_type) == UNION_TYPE)
5193 && constructor_fields)
5194 value = find_init_member (constructor_fields);
5195 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5196 value = find_init_member (constructor_index);
5197 }
5198
5199 p = XNEW (struct constructor_stack);
5200 p->type = constructor_type;
5201 p->fields = constructor_fields;
5202 p->index = constructor_index;
5203 p->max_index = constructor_max_index;
5204 p->unfilled_index = constructor_unfilled_index;
5205 p->unfilled_fields = constructor_unfilled_fields;
5206 p->bit_index = constructor_bit_index;
5207 p->elements = constructor_elements;
5208 p->constant = constructor_constant;
5209 p->simple = constructor_simple;
5210 p->erroneous = constructor_erroneous;
5211 p->pending_elts = constructor_pending_elts;
5212 p->depth = constructor_depth;
5213 p->replacement_value.value = 0;
5214 p->replacement_value.original_code = ERROR_MARK;
5215 p->implicit = implicit;
5216 p->outer = 0;
5217 p->incremental = constructor_incremental;
5218 p->designated = constructor_designated;
5219 p->next = constructor_stack;
5220 p->range_stack = 0;
5221 constructor_stack = p;
5222
5223 constructor_constant = 1;
5224 constructor_simple = 1;
5225 constructor_depth = SPELLING_DEPTH ();
5226 constructor_elements = 0;
5227 constructor_incremental = 1;
5228 constructor_designated = 0;
5229 constructor_pending_elts = 0;
5230 if (!implicit)
5231 {
5232 p->range_stack = constructor_range_stack;
5233 constructor_range_stack = 0;
5234 designator_depth = 0;
5235 designator_erroneous = 0;
5236 }
5237
5238 /* Don't die if an entire brace-pair level is superfluous
5239 in the containing level. */
5240 if (constructor_type == 0)
5241 ;
5242 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5243 || TREE_CODE (constructor_type) == UNION_TYPE)
5244 {
5245 /* Don't die if there are extra init elts at the end. */
5246 if (constructor_fields == 0)
5247 constructor_type = 0;
5248 else
5249 {
5250 constructor_type = TREE_TYPE (constructor_fields);
5251 push_member_name (constructor_fields);
5252 constructor_depth++;
5253 }
5254 }
5255 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5256 {
5257 constructor_type = TREE_TYPE (constructor_type);
5258 push_array_bounds (tree_low_cst (constructor_index, 1));
5259 constructor_depth++;
5260 }
5261
5262 if (constructor_type == 0)
5263 {
5264 error_init ("extra brace group at end of initializer");
5265 constructor_fields = 0;
5266 constructor_unfilled_fields = 0;
5267 return;
5268 }
5269
5270 if (value && TREE_CODE (value) == CONSTRUCTOR)
5271 {
5272 constructor_constant = TREE_CONSTANT (value);
5273 constructor_simple = TREE_STATIC (value);
5274 constructor_elements = CONSTRUCTOR_ELTS (value);
5275 if (!VEC_empty (constructor_elt, constructor_elements)
5276 && (TREE_CODE (constructor_type) == RECORD_TYPE
5277 || TREE_CODE (constructor_type) == ARRAY_TYPE))
5278 set_nonincremental_init ();
5279 }
5280
5281 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
5282 {
5283 missing_braces_mentioned = 1;
5284 warning_init ("missing braces around initializer");
5285 }
5286
5287 if (TREE_CODE (constructor_type) == RECORD_TYPE
5288 || TREE_CODE (constructor_type) == UNION_TYPE)
5289 {
5290 constructor_fields = TYPE_FIELDS (constructor_type);
5291 /* Skip any nameless bit fields at the beginning. */
5292 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5293 && DECL_NAME (constructor_fields) == 0)
5294 constructor_fields = TREE_CHAIN (constructor_fields);
5295
5296 constructor_unfilled_fields = constructor_fields;
5297 constructor_bit_index = bitsize_zero_node;
5298 }
5299 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5300 {
5301 /* Vectors are like simple fixed-size arrays. */
5302 constructor_max_index =
5303 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5304 constructor_index = convert (bitsizetype, integer_zero_node);
5305 constructor_unfilled_index = constructor_index;
5306 }
5307 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5308 {
5309 if (TYPE_DOMAIN (constructor_type))
5310 {
5311 constructor_max_index
5312 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5313
5314 /* Detect non-empty initializations of zero-length arrays. */
5315 if (constructor_max_index == NULL_TREE
5316 && TYPE_SIZE (constructor_type))
5317 constructor_max_index = build_int_cst (NULL_TREE, -1);
5318
5319 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5320 to initialize VLAs will cause a proper error; avoid tree
5321 checking errors as well by setting a safe value. */
5322 if (constructor_max_index
5323 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5324 constructor_max_index = build_int_cst (NULL_TREE, -1);
5325
5326 constructor_index
5327 = convert (bitsizetype,
5328 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5329 }
5330 else
5331 constructor_index = bitsize_zero_node;
5332
5333 constructor_unfilled_index = constructor_index;
5334 if (value && TREE_CODE (value) == STRING_CST)
5335 {
5336 /* We need to split the char/wchar array into individual
5337 characters, so that we don't have to special case it
5338 everywhere. */
5339 set_nonincremental_init_from_string (value);
5340 }
5341 }
5342 else
5343 {
5344 if (constructor_type != error_mark_node)
5345 warning_init ("braces around scalar initializer");
5346 constructor_fields = constructor_type;
5347 constructor_unfilled_fields = constructor_type;
5348 }
5349}
5350
5351/* At the end of an implicit or explicit brace level,
5352 finish up that level of constructor. If a single expression
5353 with redundant braces initialized that level, return the
5354 c_expr structure for that expression. Otherwise, the original_code
5355 element is set to ERROR_MARK.
5356 If we were outputting the elements as they are read, return 0 as the value
5357 from inner levels (process_init_element ignores that),
5358 but return error_mark_node as the value from the outermost level
5359 (that's what we want to put in DECL_INITIAL).
5360 Otherwise, return a CONSTRUCTOR expression as the value. */
5361
5362struct c_expr
5363pop_init_level (int implicit)
5364{
5365 struct constructor_stack *p;
5366 struct c_expr ret;
5367 ret.value = 0;
5368 ret.original_code = ERROR_MARK;
5369
5370 if (implicit == 0)
5371 {
5372 /* When we come to an explicit close brace,
5373 pop any inner levels that didn't have explicit braces. */
5374 while (constructor_stack->implicit)
5375 process_init_element (pop_init_level (1));
5376
5377 gcc_assert (!constructor_range_stack);
5378 }
5379
5380 /* Now output all pending elements. */
5381 constructor_incremental = 1;
5382 output_pending_init_elements (1);
5383
5384 p = constructor_stack;
5385
5386 /* Error for initializing a flexible array member, or a zero-length
5387 array member in an inappropriate context. */
5388 if (constructor_type && constructor_fields
5389 && TREE_CODE (constructor_type) == ARRAY_TYPE
5390 && TYPE_DOMAIN (constructor_type)
5391 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5392 {
5393 /* Silently discard empty initializations. The parser will
5394 already have pedwarned for empty brackets. */
5395 if (integer_zerop (constructor_unfilled_index))
5396 constructor_type = NULL_TREE;
5397 else
5398 {
5399 gcc_assert (!TYPE_SIZE (constructor_type));
5400
5401 if (constructor_depth > 2)
5402 error_init ("initialization of flexible array member in a nested context");
5403 else if (pedantic)
5404 pedwarn_init ("initialization of a flexible array member");
5405
5406 /* We have already issued an error message for the existence
5407 of a flexible array member not at the end of the structure.
5408 Discard the initializer so that we do not die later. */
5409 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5410 constructor_type = NULL_TREE;
5411 }
5412 }
5413
5414 /* Warn when some struct elements are implicitly initialized to zero. */
5415 if (warn_missing_field_initializers
5416 && constructor_type
5417 && TREE_CODE (constructor_type) == RECORD_TYPE
5418 && constructor_unfilled_fields)
5419 {
5420 /* Do not warn for flexible array members or zero-length arrays. */
5421 while (constructor_unfilled_fields
5422 && (!DECL_SIZE (constructor_unfilled_fields)
5423 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5424 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5425
5426 /* Do not warn if this level of the initializer uses member
5427 designators; it is likely to be deliberate. */
5428 if (constructor_unfilled_fields && !constructor_designated)
5429 {
5430 push_member_name (constructor_unfilled_fields);
5431 warning_init ("missing initializer");
5432 RESTORE_SPELLING_DEPTH (constructor_depth);
5433 }
5434 }
5435
5436 /* Pad out the end of the structure. */
5437 if (p->replacement_value.value)
5438 /* If this closes a superfluous brace pair,
5439 just pass out the element between them. */
5440 ret = p->replacement_value;
5441 else if (constructor_type == 0)
5442 ;
5443 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5444 && TREE_CODE (constructor_type) != UNION_TYPE
5445 && TREE_CODE (constructor_type) != ARRAY_TYPE
5446 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5447 {
5448 /* A nonincremental scalar initializer--just return
5449 the element, after verifying there is just one. */
5450 if (VEC_empty (constructor_elt,constructor_elements))
5451 {
5452 if (!constructor_erroneous)
5453 error_init ("empty scalar initializer");
5454 ret.value = error_mark_node;
5455 }
5456 else if (VEC_length (constructor_elt,constructor_elements) != 1)
5457 {
5458 error_init ("extra elements in scalar initializer");
5459 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5460 }
5461 else
5462 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5463 }
5464 else
5465 {
5466 if (constructor_erroneous)
5467 ret.value = error_mark_node;
5468 else
5469 {
5470 ret.value = build_constructor (constructor_type,
5471 constructor_elements);
5472 if (constructor_constant)
5473 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5474 if (constructor_constant && constructor_simple)
5475 TREE_STATIC (ret.value) = 1;
5476 }
5477 }
5478
5479 constructor_type = p->type;
5480 constructor_fields = p->fields;
5481 constructor_index = p->index;
5482 constructor_max_index = p->max_index;
5483 constructor_unfilled_index = p->unfilled_index;
5484 constructor_unfilled_fields = p->unfilled_fields;
5485 constructor_bit_index = p->bit_index;
5486 constructor_elements = p->elements;
5487 constructor_constant = p->constant;
5488 constructor_simple = p->simple;
5489 constructor_erroneous = p->erroneous;
5490 constructor_incremental = p->incremental;
5491 constructor_designated = p->designated;
5492 constructor_pending_elts = p->pending_elts;
5493 constructor_depth = p->depth;
5494 if (!p->implicit)
5495 constructor_range_stack = p->range_stack;
5496 RESTORE_SPELLING_DEPTH (constructor_depth);
5497
5498 constructor_stack = p->next;
5499 free (p);
5500
5501 if (ret.value == 0 && constructor_stack == 0)
5502 ret.value = error_mark_node;
5503 return ret;
5504}
5505
5506/* Common handling for both array range and field name designators.
5507 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5508
5509static int
5510set_designator (int array)
5511{
5512 tree subtype;
5513 enum tree_code subcode;
5514
5515 /* Don't die if an entire brace-pair level is superfluous
5516 in the containing level. */
5517 if (constructor_type == 0)
5518 return 1;
5519
5520 /* If there were errors in this designator list already, bail out
5521 silently. */
5522 if (designator_erroneous)
5523 return 1;
5524
5525 if (!designator_depth)
5526 {
5527 gcc_assert (!constructor_range_stack);
5528
5529 /* Designator list starts at the level of closest explicit
5530 braces. */
5531 while (constructor_stack->implicit)
5532 process_init_element (pop_init_level (1));
5533 constructor_designated = 1;
5534 return 0;
5535 }
5536
5537 switch (TREE_CODE (constructor_type))
5538 {
5539 case RECORD_TYPE:
5540 case UNION_TYPE:
5541 subtype = TREE_TYPE (constructor_fields);
5542 if (subtype != error_mark_node)
5543 subtype = TYPE_MAIN_VARIANT (subtype);
5544 break;
5545 case ARRAY_TYPE:
5546 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5547 break;
5548 default:
5549 gcc_unreachable ();
5550 }
5551
5552 subcode = TREE_CODE (subtype);
5553 if (array && subcode != ARRAY_TYPE)
5554 {
5555 error_init ("array index in non-array initializer");
5556 return 1;
5557 }
5558 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5559 {
5560 error_init ("field name not in record or union initializer");
5561 return 1;
5562 }
5563
5564 constructor_designated = 1;
5565 push_init_level (2);
5566 return 0;
5567}
5568
5569/* If there are range designators in designator list, push a new designator
5570 to constructor_range_stack. RANGE_END is end of such stack range or
5571 NULL_TREE if there is no range designator at this level. */
5572
5573static void
5574push_range_stack (tree range_end)
5575{
5576 struct constructor_range_stack *p;
5577
5578 p = GGC_NEW (struct constructor_range_stack);
5579 p->prev = constructor_range_stack;
5580 p->next = 0;
5581 p->fields = constructor_fields;
5582 p->range_start = constructor_index;
5583 p->index = constructor_index;
5584 p->stack = constructor_stack;
5585 p->range_end = range_end;
5586 if (constructor_range_stack)
5587 constructor_range_stack->next = p;
5588 constructor_range_stack = p;
5589}
5590
5591/* Within an array initializer, specify the next index to be initialized.
5592 FIRST is that index. If LAST is nonzero, then initialize a range
5593 of indices, running from FIRST through LAST. */
5594
5595void
5596set_init_index (tree first, tree last)
5597{
5598 if (set_designator (1))
5599 return;
5600
5601 designator_erroneous = 1;
5602
5603 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5604 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5605 {
5606 error_init ("array index in initializer not of integer type");
5607 return;
5608 }
5609
5610 if (TREE_CODE (first) != INTEGER_CST)
5611 error_init ("nonconstant array index in initializer");
5612 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5613 error_init ("nonconstant array index in initializer");
5614 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5615 error_init ("array index in non-array initializer");
5616 else if (tree_int_cst_sgn (first) == -1)
5617 error_init ("array index in initializer exceeds array bounds");
5618 else if (constructor_max_index
5619 && tree_int_cst_lt (constructor_max_index, first))
5620 error_init ("array index in initializer exceeds array bounds");
5621 else
5622 {
5623 constructor_index = convert (bitsizetype, first);
5624
5625 if (last)
5626 {
5627 if (tree_int_cst_equal (first, last))
5628 last = 0;
5629 else if (tree_int_cst_lt (last, first))
5630 {
5631 error_init ("empty index range in initializer");
5632 last = 0;
5633 }
5634 else
5635 {
5636 last = convert (bitsizetype, last);
5637 if (constructor_max_index != 0
5638 && tree_int_cst_lt (constructor_max_index, last))
5639 {
5640 error_init ("array index range in initializer exceeds array bounds");
5641 last = 0;
5642 }
5643 }
5644 }
5645
5646 designator_depth++;
5647 designator_erroneous = 0;
5648 if (constructor_range_stack || last)
5649 push_range_stack (last);
5650 }
5651}
5652
5653/* Within a struct initializer, specify the next field to be initialized. */
5654
5655void
5656set_init_label (tree fieldname)
5657{
5658 tree tail;
5659
5660 if (set_designator (0))
5661 return;
5662
5663 designator_erroneous = 1;
5664
5665 if (TREE_CODE (constructor_type) != RECORD_TYPE
5666 && TREE_CODE (constructor_type) != UNION_TYPE)
5667 {
5668 error_init ("field name not in record or union initializer");
5669 return;
5670 }
5671
5672 for (tail = TYPE_FIELDS (constructor_type); tail;
5673 tail = TREE_CHAIN (tail))
5674 {
5675 if (DECL_NAME (tail) == fieldname)
5676 break;
5677 }
5678
5679 if (tail == 0)
5680 error ("unknown field %qE specified in initializer", fieldname);
5681 else
5682 {
5683 constructor_fields = tail;
5684 designator_depth++;
5685 designator_erroneous = 0;
5686 if (constructor_range_stack)
5687 push_range_stack (NULL_TREE);
5688 }
5689}
5690
5691/* Add a new initializer to the tree of pending initializers. PURPOSE
5692 identifies the initializer, either array index or field in a structure.
5693 VALUE is the value of that index or field. */
5694
5695static void
5696add_pending_init (tree purpose, tree value)
5697{
5698 struct init_node *p, **q, *r;
5699
5700 q = &constructor_pending_elts;
5701 p = 0;
5702
5703 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5704 {
5705 while (*q != 0)
5706 {
5707 p = *q;
5708 if (tree_int_cst_lt (purpose, p->purpose))
5709 q = &p->left;
5710 else if (tree_int_cst_lt (p->purpose, purpose))
5711 q = &p->right;
5712 else
5713 {
5714 if (TREE_SIDE_EFFECTS (p->value))
5715 warning_init ("initialized field with side-effects overwritten");
5716 else if (warn_override_init)
5717 warning_init ("initialized field overwritten");
5718 p->value = value;
5719 return;
5720 }
5721 }
5722 }
5723 else
5724 {
5725 tree bitpos;
5726
5727 bitpos = bit_position (purpose);
5728 while (*q != NULL)
5729 {
5730 p = *q;
5731 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5732 q = &p->left;
5733 else if (p->purpose != purpose)
5734 q = &p->right;
5735 else
5736 {
5737 if (TREE_SIDE_EFFECTS (p->value))
5738 warning_init ("initialized field with side-effects overwritten");
5739 else if (warn_override_init)
5740 warning_init ("initialized field overwritten");
5741 p->value = value;
5742 return;
5743 }
5744 }
5745 }
5746
5747 r = GGC_NEW (struct init_node);
5748 r->purpose = purpose;
5749 r->value = value;
5750
5751 *q = r;
5752 r->parent = p;
5753 r->left = 0;
5754 r->right = 0;
5755 r->balance = 0;
5756
5757 while (p)
5758 {
5759 struct init_node *s;
5760
5761 if (r == p->left)
5762 {
5763 if (p->balance == 0)
5764 p->balance = -1;
5765 else if (p->balance < 0)
5766 {
5767 if (r->balance < 0)
5768 {
5769 /* L rotation. */
5770 p->left = r->right;
5771 if (p->left)
5772 p->left->parent = p;
5773 r->right = p;
5774
5775 p->balance = 0;
5776 r->balance = 0;
5777
5778 s = p->parent;
5779 p->parent = r;
5780 r->parent = s;
5781 if (s)
5782 {
5783 if (s->left == p)
5784 s->left = r;
5785 else
5786 s->right = r;
5787 }
5788 else
5789 constructor_pending_elts = r;
5790 }
5791 else
5792 {
5793 /* LR rotation. */
5794 struct init_node *t = r->right;
5795
5796 r->right = t->left;
5797 if (r->right)
5798 r->right->parent = r;
5799 t->left = r;
5800
5801 p->left = t->right;
5802 if (p->left)
5803 p->left->parent = p;
5804 t->right = p;
5805
5806 p->balance = t->balance < 0;
5807 r->balance = -(t->balance > 0);
5808 t->balance = 0;
5809
5810 s = p->parent;
5811 p->parent = t;
5812 r->parent = t;
5813 t->parent = s;
5814 if (s)
5815 {
5816 if (s->left == p)
5817 s->left = t;
5818 else
5819 s->right = t;
5820 }
5821 else
5822 constructor_pending_elts = t;
5823 }
5824 break;
5825 }
5826 else
5827 {
5828 /* p->balance == +1; growth of left side balances the node. */
5829 p->balance = 0;
5830 break;
5831 }
5832 }
5833 else /* r == p->right */
5834 {
5835 if (p->balance == 0)
5836 /* Growth propagation from right side. */
5837 p->balance++;
5838 else if (p->balance > 0)
5839 {
5840 if (r->balance > 0)
5841 {
5842 /* R rotation. */
5843 p->right = r->left;
5844 if (p->right)
5845 p->right->parent = p;
5846 r->left = p;
5847
5848 p->balance = 0;
5849 r->balance = 0;
5850
5851 s = p->parent;
5852 p->parent = r;
5853 r->parent = s;
5854 if (s)
5855 {
5856 if (s->left == p)
5857 s->left = r;
5858 else
5859 s->right = r;
5860 }
5861 else
5862 constructor_pending_elts = r;
5863 }
5864 else /* r->balance == -1 */
5865 {
5866 /* RL rotation */
5867 struct init_node *t = r->left;
5868
5869 r->left = t->right;
5870 if (r->left)
5871 r->left->parent = r;
5872 t->right = r;
5873
5874 p->right = t->left;
5875 if (p->right)
5876 p->right->parent = p;
5877 t->left = p;
5878
5879 r->balance = (t->balance < 0);
5880 p->balance = -(t->balance > 0);
5881 t->balance = 0;
5882
5883 s = p->parent;
5884 p->parent = t;
5885 r->parent = t;
5886 t->parent = s;
5887 if (s)
5888 {
5889 if (s->left == p)
5890 s->left = t;
5891 else
5892 s->right = t;
5893 }
5894 else
5895 constructor_pending_elts = t;
5896 }
5897 break;
5898 }
5899 else
5900 {
5901 /* p->balance == -1; growth of right side balances the node. */
5902 p->balance = 0;
5903 break;
5904 }
5905 }
5906
5907 r = p;
5908 p = p->parent;
5909 }
5910}
5911
5912/* Build AVL tree from a sorted chain. */
5913
5914static void
5915set_nonincremental_init (void)
5916{
5917 unsigned HOST_WIDE_INT ix;
5918 tree index, value;
5919
5920 if (TREE_CODE (constructor_type) != RECORD_TYPE
5921 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5922 return;
5923
5924 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value)
5925 add_pending_init (index, value);
5926 constructor_elements = 0;
5927 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5928 {
5929 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5930 /* Skip any nameless bit fields at the beginning. */
5931 while (constructor_unfilled_fields != 0
5932 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5933 && DECL_NAME (constructor_unfilled_fields) == 0)
5934 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5935
5936 }
5937 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5938 {
5939 if (TYPE_DOMAIN (constructor_type))
5940 constructor_unfilled_index
5941 = convert (bitsizetype,
5942 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5943 else
5944 constructor_unfilled_index = bitsize_zero_node;
5945 }
5946 constructor_incremental = 0;
5947}
5948
5949/* Build AVL tree from a string constant. */
5950
5951static void
5952set_nonincremental_init_from_string (tree str)
5953{
5954 tree value, purpose, type;
5955 HOST_WIDE_INT val[2];
5956 const char *p, *end;
5957 int byte, wchar_bytes, charwidth, bitpos;
5958
5959 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5960
5961 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5962 == TYPE_PRECISION (char_type_node))
5963 wchar_bytes = 1;
5964 else
5965 {
5966 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5967 == TYPE_PRECISION (wchar_type_node));
5968 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5969 }
5970 charwidth = TYPE_PRECISION (char_type_node);
5971 type = TREE_TYPE (constructor_type);
5972 p = TREE_STRING_POINTER (str);
5973 end = p + TREE_STRING_LENGTH (str);
5974
5975 for (purpose = bitsize_zero_node;
5976 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5977 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5978 {
5979 if (wchar_bytes == 1)
5980 {
5981 val[1] = (unsigned char) *p++;
5982 val[0] = 0;
5983 }
5984 else
5985 {
5986 val[0] = 0;
5987 val[1] = 0;
5988 for (byte = 0; byte < wchar_bytes; byte++)
5989 {
5990 if (BYTES_BIG_ENDIAN)
5991 bitpos = (wchar_bytes - byte - 1) * charwidth;
5992 else
5993 bitpos = byte * charwidth;
5994 val[bitpos < HOST_BITS_PER_WIDE_INT]
5995 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5996 << (bitpos % HOST_BITS_PER_WIDE_INT);
5997 }
5998 }
5999
6000 if (!TYPE_UNSIGNED (type))
6001 {
6002 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
6003 if (bitpos < HOST_BITS_PER_WIDE_INT)
6004 {
6005 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
6006 {
6007 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
6008 val[0] = -1;
6009 }
6010 }
6011 else if (bitpos == HOST_BITS_PER_WIDE_INT)
6012 {
6013 if (val[1] < 0)
6014 val[0] = -1;
6015 }
6016 else if (val[0] & (((HOST_WIDE_INT) 1)
6017 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
6018 val[0] |= ((HOST_WIDE_INT) -1)
6019 << (bitpos - HOST_BITS_PER_WIDE_INT);
6020 }
6021
6022 value = build_int_cst_wide (type, val[1], val[0]);
6023 add_pending_init (purpose, value);
6024 }
6025
6026 constructor_incremental = 0;
6027}
6028
6029/* Return value of FIELD in pending initializer or zero if the field was
6030 not initialized yet. */
6031
6032static tree
6033find_init_member (tree field)
6034{
6035 struct init_node *p;
6036
6037 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6038 {
6039 if (constructor_incremental
6040 && tree_int_cst_lt (field, constructor_unfilled_index))
6041 set_nonincremental_init ();
6042
6043 p = constructor_pending_elts;
6044 while (p)
6045 {
6046 if (tree_int_cst_lt (field, p->purpose))
6047 p = p->left;
6048 else if (tree_int_cst_lt (p->purpose, field))
6049 p = p->right;
6050 else
6051 return p->value;
6052 }
6053 }
6054 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6055 {
6056 tree bitpos = bit_position (field);
6057
6058 if (constructor_incremental
6059 && (!constructor_unfilled_fields
6060 || tree_int_cst_lt (bitpos,
6061 bit_position (constructor_unfilled_fields))))
6062 set_nonincremental_init ();
6063
6064 p = constructor_pending_elts;
6065 while (p)
6066 {
6067 if (field == p->purpose)
6068 return p->value;
6069 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
6070 p = p->left;
6071 else
6072 p = p->right;
6073 }
6074 }
6075 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6076 {
6077 if (!VEC_empty (constructor_elt, constructor_elements)
6078 && (VEC_last (constructor_elt, constructor_elements)->index
6079 == field))
6080 return VEC_last (constructor_elt, constructor_elements)->value;
6081 }
6082 return 0;
6083}
6084
6085/* "Output" the next constructor element.
6086 At top level, really output it to assembler code now.
6087 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6088 TYPE is the data type that the containing data type wants here.
6089 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6090 If VALUE is a string constant, STRICT_STRING is true if it is
6091 unparenthesized or we should not warn here for it being parenthesized.
6092 For other types of VALUE, STRICT_STRING is not used.
6093
6094 PENDING if non-nil means output pending elements that belong
6095 right after this element. (PENDING is normally 1;
6096 it is 0 while outputting pending elements, to avoid recursion.) */
6097
6098static void
6099output_init_element (tree value, bool strict_string, tree type, tree field,
6100 int pending)
6101{
6102 constructor_elt *celt;
6103
6104 if (type == error_mark_node || value == error_mark_node)
6105 {
6106 constructor_erroneous = 1;
6107 return;
6108 }
6109 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
6110 && (TREE_CODE (value) == STRING_CST
6111 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
6112 && !(TREE_CODE (value) == STRING_CST
6113 && TREE_CODE (type) == ARRAY_TYPE
6114 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
6115 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
6116 TYPE_MAIN_VARIANT (type)))
6117 value = array_to_pointer_conversion (value);
6118
6119 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
6120 && require_constant_value && !flag_isoc99 && pending)
6121 {
6122 /* As an extension, allow initializing objects with static storage
6123 duration with compound literals (which are then treated just as
6124 the brace enclosed list they contain). */
6125 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
6126 value = DECL_INITIAL (decl);
6127 }
6128
6129 if (value == error_mark_node)
6130 constructor_erroneous = 1;
6131 else if (!TREE_CONSTANT (value))
6132 constructor_constant = 0;
6133 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
6134 || ((TREE_CODE (constructor_type) == RECORD_TYPE
6135 || TREE_CODE (constructor_type) == UNION_TYPE)
6136 && DECL_C_BIT_FIELD (field)
6137 && TREE_CODE (value) != INTEGER_CST))
6138 constructor_simple = 0;
6139
6140 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
6141 {
6142 if (require_constant_value)
6143 {
6144 error_init ("initializer element is not constant");
6145 value = error_mark_node;
6146 }
6147 else if (require_constant_elements)
6148 pedwarn ("initializer element is not computable at load time");
6149 }
6150
6151 /* If this field is empty (and not at the end of structure),
6152 don't do anything other than checking the initializer. */
6153 if (field
6154 && (TREE_TYPE (field) == error_mark_node
6155 || (COMPLETE_TYPE_P (TREE_TYPE (field))
6156 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
6157 && (TREE_CODE (constructor_type) == ARRAY_TYPE
6158 || TREE_CHAIN (field)))))
6159 return;
6160
6161 value = digest_init (type, value, strict_string, require_constant_value);
6162 if (value == error_mark_node)
6163 {
6164 constructor_erroneous = 1;
6165 return;
6166 }
6167
6168 /* If this element doesn't come next in sequence,
6169 put it on constructor_pending_elts. */
6170 if (TREE_CODE (constructor_type) == ARRAY_TYPE
6171 && (!constructor_incremental
6172 || !tree_int_cst_equal (field, constructor_unfilled_index)))
6173 {
6174 if (constructor_incremental
6175 && tree_int_cst_lt (field, constructor_unfilled_index))
6176 set_nonincremental_init ();
6177
6178 add_pending_init (field, value);
6179 return;
6180 }
6181 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6182 && (!constructor_incremental
6183 || field != constructor_unfilled_fields))
6184 {
6185 /* We do this for records but not for unions. In a union,
6186 no matter which field is specified, it can be initialized
6187 right away since it starts at the beginning of the union. */
6188 if (constructor_incremental)
6189 {
6190 if (!constructor_unfilled_fields)
6191 set_nonincremental_init ();
6192 else
6193 {
6194 tree bitpos, unfillpos;
6195
6196 bitpos = bit_position (field);
6197 unfillpos = bit_position (constructor_unfilled_fields);
6198
6199 if (tree_int_cst_lt (bitpos, unfillpos))
6200 set_nonincremental_init ();
6201 }
6202 }
6203
6204 add_pending_init (field, value);
6205 return;
6206 }
6207 else if (TREE_CODE (constructor_type) == UNION_TYPE
6208 && !VEC_empty (constructor_elt, constructor_elements))
6209 {
6210 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt,
6211 constructor_elements)->value))
6212 warning_init ("initialized field with side-effects overwritten");
6213 else if (warn_override_init)
6214 warning_init ("initialized field overwritten");
6215
6216 /* We can have just one union field set. */
6217 constructor_elements = 0;
6218 }
6219
6220 /* Otherwise, output this element either to
6221 constructor_elements or to the assembler file. */
6222
6223 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL);
6224 celt->index = field;
6225 celt->value = value;
6226
6227 /* Advance the variable that indicates sequential elements output. */
6228 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6229 constructor_unfilled_index
6230 = size_binop (PLUS_EXPR, constructor_unfilled_index,
6231 bitsize_one_node);
6232 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6233 {
6234 constructor_unfilled_fields
6235 = TREE_CHAIN (constructor_unfilled_fields);
6236
6237 /* Skip any nameless bit fields. */
6238 while (constructor_unfilled_fields != 0
6239 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6240 && DECL_NAME (constructor_unfilled_fields) == 0)
6241 constructor_unfilled_fields =
6242 TREE_CHAIN (constructor_unfilled_fields);
6243 }
6244 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6245 constructor_unfilled_fields = 0;
6246
6247 /* Now output any pending elements which have become next. */
6248 if (pending)
6249 output_pending_init_elements (0);
6250}
6251
6252/* Output any pending elements which have become next.
6253 As we output elements, constructor_unfilled_{fields,index}
6254 advances, which may cause other elements to become next;
6255 if so, they too are output.
6256
6257 If ALL is 0, we return when there are
6258 no more pending elements to output now.
6259
6260 If ALL is 1, we output space as necessary so that
6261 we can output all the pending elements. */
6262
6263static void
6264output_pending_init_elements (int all)
6265{
6266 struct init_node *elt = constructor_pending_elts;
6267 tree next;
6268
6269 retry:
6270
6271 /* Look through the whole pending tree.
6272 If we find an element that should be output now,
6273 output it. Otherwise, set NEXT to the element
6274 that comes first among those still pending. */
6275
6276 next = 0;
6277 while (elt)
6278 {
6279 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6280 {
6281 if (tree_int_cst_equal (elt->purpose,
6282 constructor_unfilled_index))
6283 output_init_element (elt->value, true,
6284 TREE_TYPE (constructor_type),
6285 constructor_unfilled_index, 0);
6286 else if (tree_int_cst_lt (constructor_unfilled_index,
6287 elt->purpose))
6288 {
6289 /* Advance to the next smaller node. */
6290 if (elt->left)
6291 elt = elt->left;
6292 else
6293 {
6294 /* We have reached the smallest node bigger than the
6295 current unfilled index. Fill the space first. */
6296 next = elt->purpose;
6297 break;
6298 }
6299 }
6300 else
6301 {
6302 /* Advance to the next bigger node. */
6303 if (elt->right)
6304 elt = elt->right;
6305 else
6306 {
6307 /* We have reached the biggest node in a subtree. Find
6308 the parent of it, which is the next bigger node. */
6309 while (elt->parent && elt->parent->right == elt)
6310 elt = elt->parent;
6311 elt = elt->parent;
6312 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6313 elt->purpose))
6314 {
6315 next = elt->purpose;
6316 break;
6317 }
6318 }
6319 }
6320 }
6321 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6322 || TREE_CODE (constructor_type) == UNION_TYPE)
6323 {
6324 tree ctor_unfilled_bitpos, elt_bitpos;
6325
6326 /* If the current record is complete we are done. */
6327 if (constructor_unfilled_fields == 0)
6328 break;
6329
6330 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
6331 elt_bitpos = bit_position (elt->purpose);
6332 /* We can't compare fields here because there might be empty
6333 fields in between. */
6334 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6335 {
6336 constructor_unfilled_fields = elt->purpose;
6337 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6338 elt->purpose, 0);
6339 }
6340 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6341 {
6342 /* Advance to the next smaller node. */
6343 if (elt->left)
6344 elt = elt->left;
6345 else
6346 {
6347 /* We have reached the smallest node bigger than the
6348 current unfilled field. Fill the space first. */
6349 next = elt->purpose;
6350 break;
6351 }
6352 }
6353 else
6354 {
6355 /* Advance to the next bigger node. */
6356 if (elt->right)
6357 elt = elt->right;
6358 else
6359 {
6360 /* We have reached the biggest node in a subtree. Find
6361 the parent of it, which is the next bigger node. */
6362 while (elt->parent && elt->parent->right == elt)
6363 elt = elt->parent;
6364 elt = elt->parent;
6365 if (elt
6366 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6367 bit_position (elt->purpose))))
6368 {
6369 next = elt->purpose;
6370 break;
6371 }
6372 }
6373 }
6374 }
6375 }
6376
6377 /* Ordinarily return, but not if we want to output all
6378 and there are elements left. */
6379 if (!(all && next != 0))
6380 return;
6381
6382 /* If it's not incremental, just skip over the gap, so that after
6383 jumping to retry we will output the next successive element. */
6384 if (TREE_CODE (constructor_type) == RECORD_TYPE
6385 || TREE_CODE (constructor_type) == UNION_TYPE)
6386 constructor_unfilled_fields = next;
6387 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6388 constructor_unfilled_index = next;
6389
6390 /* ELT now points to the node in the pending tree with the next
6391 initializer to output. */
6392 goto retry;
6393}
6394
6395/* Add one non-braced element to the current constructor level.
6396 This adjusts the current position within the constructor's type.
6397 This may also start or terminate implicit levels
6398 to handle a partly-braced initializer.
6399
6400 Once this has found the correct level for the new element,
6401 it calls output_init_element. */
6402
6403void
6404process_init_element (struct c_expr value)
6405{
6406 tree orig_value = value.value;
6407 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6408 bool strict_string = value.original_code == STRING_CST;
6409
6410 designator_depth = 0;
6411 designator_erroneous = 0;
6412
6413 /* Handle superfluous braces around string cst as in
6414 char x[] = {"foo"}; */
6415 if (string_flag
6416 && constructor_type
6417 && TREE_CODE (constructor_type) == ARRAY_TYPE
6418 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6419 && integer_zerop (constructor_unfilled_index))
6420 {
6421 if (constructor_stack->replacement_value.value)
6422 error_init ("excess elements in char array initializer");
6423 constructor_stack->replacement_value = value;
6424 return;
6425 }
6426
6427 if (constructor_stack->replacement_value.value != 0)
6428 {
6429 error_init ("excess elements in struct initializer");
6430 return;
6431 }
6432
6433 /* Ignore elements of a brace group if it is entirely superfluous
6434 and has already been diagnosed. */
6435 if (constructor_type == 0)
6436 return;
6437
6438 /* If we've exhausted any levels that didn't have braces,
6439 pop them now. */
6440 while (constructor_stack->implicit)
6441 {
6442 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6443 || TREE_CODE (constructor_type) == UNION_TYPE)
6444 && constructor_fields == 0)
6445 process_init_element (pop_init_level (1));
6446 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6447 && (constructor_max_index == 0
6448 || tree_int_cst_lt (constructor_max_index,
6449 constructor_index)))
6450 process_init_element (pop_init_level (1));
6451 else
6452 break;
6453 }
6454
6455 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6456 if (constructor_range_stack)
6457 {
6458 /* If value is a compound literal and we'll be just using its
6459 content, don't put it into a SAVE_EXPR. */
6460 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6461 || !require_constant_value
6462 || flag_isoc99)
6463 value.value = save_expr (value.value);
6464 }
6465
6466 while (1)
6467 {
6468 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6469 {
6470 tree fieldtype;
6471 enum tree_code fieldcode;
6472
6473 if (constructor_fields == 0)
6474 {
6475 pedwarn_init ("excess elements in struct initializer");
6476 break;
6477 }
6478
6479 fieldtype = TREE_TYPE (constructor_fields);
6480 if (fieldtype != error_mark_node)
6481 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6482 fieldcode = TREE_CODE (fieldtype);
6483
6484 /* Error for non-static initialization of a flexible array member. */
6485 if (fieldcode == ARRAY_TYPE
6486 && !require_constant_value
6487 && TYPE_SIZE (fieldtype) == NULL_TREE
6488 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6489 {
6490 error_init ("non-static initialization of a flexible array member");
6491 break;
6492 }
6493
6494 /* Accept a string constant to initialize a subarray. */
6495 if (value.value != 0
6496 && fieldcode == ARRAY_TYPE
6497 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6498 && string_flag)
6499 value.value = orig_value;
6500 /* Otherwise, if we have come to a subaggregate,
6501 and we don't have an element of its type, push into it. */
6502 else if (value.value != 0
6503 && value.value != error_mark_node
6504 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6505 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6506 || fieldcode == UNION_TYPE))
6507 {
6508 push_init_level (1);
6509 continue;
6510 }
6511
6512 if (value.value)
6513 {
6514 push_member_name (constructor_fields);
6515 output_init_element (value.value, strict_string,
6516 fieldtype, constructor_fields, 1);
6517 RESTORE_SPELLING_DEPTH (constructor_depth);
6518 }
6519 else
6520 /* Do the bookkeeping for an element that was
6521 directly output as a constructor. */
6522 {
6523 /* For a record, keep track of end position of last field. */
6524 if (DECL_SIZE (constructor_fields))
6525 constructor_bit_index
6526 = size_binop (PLUS_EXPR,
6527 bit_position (constructor_fields),
6528 DECL_SIZE (constructor_fields));
6529
6530 /* If the current field was the first one not yet written out,
6531 it isn't now, so update. */
6532 if (constructor_unfilled_fields == constructor_fields)
6533 {
6534 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6535 /* Skip any nameless bit fields. */
6536 while (constructor_unfilled_fields != 0
6537 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6538 && DECL_NAME (constructor_unfilled_fields) == 0)
6539 constructor_unfilled_fields =
6540 TREE_CHAIN (constructor_unfilled_fields);
6541 }
6542 }
6543
6544 constructor_fields = TREE_CHAIN (constructor_fields);
6545 /* Skip any nameless bit fields at the beginning. */
6546 while (constructor_fields != 0
6547 && DECL_C_BIT_FIELD (constructor_fields)
6548 && DECL_NAME (constructor_fields) == 0)
6549 constructor_fields = TREE_CHAIN (constructor_fields);
6550 }
6551 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6552 {
6553 tree fieldtype;
6554 enum tree_code fieldcode;
6555
6556 if (constructor_fields == 0)
6557 {
6558 pedwarn_init ("excess elements in union initializer");
6559 break;
6560 }
6561
6562 fieldtype = TREE_TYPE (constructor_fields);
6563 if (fieldtype != error_mark_node)
6564 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6565 fieldcode = TREE_CODE (fieldtype);
6566
6567 /* Warn that traditional C rejects initialization of unions.
6568 We skip the warning if the value is zero. This is done
6569 under the assumption that the zero initializer in user
6570 code appears conditioned on e.g. __STDC__ to avoid
6571 "missing initializer" warnings and relies on default
6572 initialization to zero in the traditional C case.
6573 We also skip the warning if the initializer is designated,
6574 again on the assumption that this must be conditional on
6575 __STDC__ anyway (and we've already complained about the
6576 member-designator already). */
6577 if (!in_system_header && !constructor_designated
6578 && !(value.value && (integer_zerop (value.value)
6579 || real_zerop (value.value))))
6580 warning (OPT_Wtraditional, "traditional C rejects initialization "
6581 "of unions");
6582
6583 /* Accept a string constant to initialize a subarray. */
6584 if (value.value != 0
6585 && fieldcode == ARRAY_TYPE
6586 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6587 && string_flag)
6588 value.value = orig_value;
6589 /* Otherwise, if we have come to a subaggregate,
6590 and we don't have an element of its type, push into it. */
6591 else if (value.value != 0
6592 && value.value != error_mark_node
6593 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6594 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6595 || fieldcode == UNION_TYPE))
6596 {
6597 push_init_level (1);
6598 continue;
6599 }
6600
6601 if (value.value)
6602 {
6603 push_member_name (constructor_fields);
6604 output_init_element (value.value, strict_string,
6605 fieldtype, constructor_fields, 1);
6606 RESTORE_SPELLING_DEPTH (constructor_depth);
6607 }
6608 else
6609 /* Do the bookkeeping for an element that was
6610 directly output as a constructor. */
6611 {
6612 constructor_bit_index = DECL_SIZE (constructor_fields);
6613 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6614 }
6615
6616 constructor_fields = 0;
6617 }
6618 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6619 {
6620 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6621 enum tree_code eltcode = TREE_CODE (elttype);
6622
6623 /* Accept a string constant to initialize a subarray. */
6624 if (value.value != 0
6625 && eltcode == ARRAY_TYPE
6626 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6627 && string_flag)
6628 value.value = orig_value;
6629 /* Otherwise, if we have come to a subaggregate,
6630 and we don't have an element of its type, push into it. */
6631 else if (value.value != 0
6632 && value.value != error_mark_node
6633 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6634 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6635 || eltcode == UNION_TYPE))
6636 {
6637 push_init_level (1);
6638 continue;
6639 }
6640
6641 if (constructor_max_index != 0
6642 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6643 || integer_all_onesp (constructor_max_index)))
6644 {
6645 pedwarn_init ("excess elements in array initializer");
6646 break;
6647 }
6648
6649 /* Now output the actual element. */
6650 if (value.value)
6651 {
6652 push_array_bounds (tree_low_cst (constructor_index, 1));
6653 output_init_element (value.value, strict_string,
6654 elttype, constructor_index, 1);
6655 RESTORE_SPELLING_DEPTH (constructor_depth);
6656 }
6657
6658 constructor_index
6659 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6660
6661 if (!value.value)
6662 /* If we are doing the bookkeeping for an element that was
6663 directly output as a constructor, we must update
6664 constructor_unfilled_index. */
6665 constructor_unfilled_index = constructor_index;
6666 }
6667 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6668 {
6669 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6670
6671 /* Do a basic check of initializer size. Note that vectors
6672 always have a fixed size derived from their type. */
6673 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6674 {
6675 pedwarn_init ("excess elements in vector initializer");
6676 break;
6677 }
6678
6679 /* Now output the actual element. */
6680 if (value.value)
6681 output_init_element (value.value, strict_string,
6682 elttype, constructor_index, 1);
6683
6684 constructor_index
6685 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6686
6687 if (!value.value)
6688 /* If we are doing the bookkeeping for an element that was
6689 directly output as a constructor, we must update
6690 constructor_unfilled_index. */
6691 constructor_unfilled_index = constructor_index;
6692 }
6693
6694 /* Handle the sole element allowed in a braced initializer
6695 for a scalar variable. */
6696 else if (constructor_type != error_mark_node
6697 && constructor_fields == 0)
6698 {
6699 pedwarn_init ("excess elements in scalar initializer");
6700 break;
6701 }
6702 else
6703 {
6704 if (value.value)
6705 output_init_element (value.value, strict_string,
6706 constructor_type, NULL_TREE, 1);
6707 constructor_fields = 0;
6708 }
6709
6710 /* Handle range initializers either at this level or anywhere higher
6711 in the designator stack. */
6712 if (constructor_range_stack)
6713 {
6714 struct constructor_range_stack *p, *range_stack;
6715 int finish = 0;
6716
6717 range_stack = constructor_range_stack;
6718 constructor_range_stack = 0;
6719 while (constructor_stack != range_stack->stack)
6720 {
6721 gcc_assert (constructor_stack->implicit);
6722 process_init_element (pop_init_level (1));
6723 }
6724 for (p = range_stack;
6725 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6726 p = p->prev)
6727 {
6728 gcc_assert (constructor_stack->implicit);
6729 process_init_element (pop_init_level (1));
6730 }
6731
6732 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6733 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6734 finish = 1;
6735
6736 while (1)
6737 {
6738 constructor_index = p->index;
6739 constructor_fields = p->fields;
6740 if (finish && p->range_end && p->index == p->range_start)
6741 {
6742 finish = 0;
6743 p->prev = 0;
6744 }
6745 p = p->next;
6746 if (!p)
6747 break;
6748 push_init_level (2);
6749 p->stack = constructor_stack;
6750 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6751 p->index = p->range_start;
6752 }
6753
6754 if (!finish)
6755 constructor_range_stack = range_stack;
6756 continue;
6757 }
6758
6759 break;
6760 }
6761
6762 constructor_range_stack = 0;
6763}
6764
6765/* Build a complete asm-statement, whose components are a CV_QUALIFIER
6766 (guaranteed to be 'volatile' or null) and ARGS (represented using
6767 an ASM_EXPR node). */
6768tree
6769build_asm_stmt (tree cv_qualifier, tree args)
6770{
6771 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6772 ASM_VOLATILE_P (args) = 1;
6773 return add_stmt (args);
6774}
6775
6776/* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6777 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6778 SIMPLE indicates whether there was anything at all after the
6779 string in the asm expression -- asm("blah") and asm("blah" : )
6780 are subtly different. We use a ASM_EXPR node to represent this. */
6781tree
6782build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6783 bool simple)
6784{
6785 tree tail;
6786 tree args;
6787 int i;
6788 const char *constraint;
6789 const char **oconstraints;
6790 bool allows_mem, allows_reg, is_inout;
6791 int ninputs, noutputs;
6792
6793 ninputs = list_length (inputs);
6794 noutputs = list_length (outputs);
6795 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6796
6797 string = resolve_asm_operand_names (string, outputs, inputs);
6798
6799 /* Remove output conversions that change the type but not the mode. */
6800 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6801 {
6802 tree output = TREE_VALUE (tail);
6803
6804 /* ??? Really, this should not be here. Users should be using a
6805 proper lvalue, dammit. But there's a long history of using casts
6806 in the output operands. In cases like longlong.h, this becomes a
6807 primitive form of typechecking -- if the cast can be removed, then
6808 the output operand had a type of the proper width; otherwise we'll
6809 get an error. Gross, but ... */
6810 STRIP_NOPS (output);
6811
6812 if (!lvalue_or_else (output, lv_asm))
6813 output = error_mark_node;
6814
6815 if (output != error_mark_node
6816 && (TREE_READONLY (output)
6817 || TYPE_READONLY (TREE_TYPE (output))
6818 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE
6819 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE)
6820 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output)))))
6821 readonly_error (output, lv_asm);
6822
6823 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6824 oconstraints[i] = constraint;
6825
6826 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6827 &allows_mem, &allows_reg, &is_inout))
6828 {
6829 /* If the operand is going to end up in memory,
6830 mark it addressable. */
6831 if (!allows_reg && !c_mark_addressable (output))
6832 output = error_mark_node;
6833 }
6834 else
6835 output = error_mark_node;
6836
6837 TREE_VALUE (tail) = output;
6838 }
6839
6840 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6841 {
6842 tree input;
6843
6844 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6845 input = TREE_VALUE (tail);
6846
6847 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6848 oconstraints, &allows_mem, &allows_reg))
6849 {
6850 /* If the operand is going to end up in memory,
6851 mark it addressable. */
6852 if (!allows_reg && allows_mem)
6853 {
6854 /* Strip the nops as we allow this case. FIXME, this really
6855 should be rejected or made deprecated. */
6856 STRIP_NOPS (input);
6857 if (!c_mark_addressable (input))
6858 input = error_mark_node;
6859 }
6860 }
6861 else
6862 input = error_mark_node;
6863
6864 TREE_VALUE (tail) = input;
6865 }
6866
6867 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6868
6869 /* asm statements without outputs, including simple ones, are treated
6870 as volatile. */
6871 ASM_INPUT_P (args) = simple;
6872 ASM_VOLATILE_P (args) = (noutputs == 0);
6873
6874 return args;
6875}
6876
6877/* Generate a goto statement to LABEL. */
6878
6879tree
6880c_finish_goto_label (tree label)
6881{
6882 tree decl = lookup_label (label);
6883 if (!decl)
6884 return NULL_TREE;
6885
6886 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6887 {
6888 error ("jump into statement expression");
6889 return NULL_TREE;
6890 }
6891
6892 if (C_DECL_UNJUMPABLE_VM (decl))
6893 {
6894 error ("jump into scope of identifier with variably modified type");
6895 return NULL_TREE;
6896 }
6897
6898 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6899 {
6900 /* No jump from outside this statement expression context, so
6901 record that there is a jump from within this context. */
6902 struct c_label_list *nlist;
6903 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6904 nlist->next = label_context_stack_se->labels_used;
6905 nlist->label = decl;
6906 label_context_stack_se->labels_used = nlist;
6907 }
6908
6909 if (!C_DECL_UNDEFINABLE_VM (decl))
6910 {
6911 /* No jump from outside this context context of identifiers with
6912 variably modified type, so record that there is a jump from
6913 within this context. */
6914 struct c_label_list *nlist;
6915 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6916 nlist->next = label_context_stack_vm->labels_used;
6917 nlist->label = decl;
6918 label_context_stack_vm->labels_used = nlist;
6919 }
6920
6921 TREE_USED (decl) = 1;
6922 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6923}
6924
6925/* Generate a computed goto statement to EXPR. */
6926
6927tree
6928c_finish_goto_ptr (tree expr)
6929{
6930 if (pedantic)
6931 pedwarn ("ISO C forbids %<goto *expr;%>");
6932 expr = convert (ptr_type_node, expr);
6933 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6934}
6935
6936/* Generate a C `return' statement. RETVAL is the expression for what
6937 to return, or a null pointer for `return;' with no value. */
6938
6939tree
6940c_finish_return (tree retval)
6941{
6942 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt;
6943 bool no_warning = false;
6944
6945 if (TREE_THIS_VOLATILE (current_function_decl))
6946 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6947
6948 if (!retval)
6949 {
6950 current_function_returns_null = 1;
6951 if ((warn_return_type || flag_isoc99)
6952 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6953 {
6954 pedwarn_c99 ("%<return%> with no value, in "
6955 "function returning non-void");
6956 no_warning = true;
6957 }
6958 }
6959 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6960 {
6961 current_function_returns_null = 1;
6962 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6963 pedwarn ("%<return%> with a value, in function returning void");
6964 }
6965 else
6966 {
6967 tree t = convert_for_assignment (valtype, retval, ic_return,
6968 NULL_TREE, NULL_TREE, 0);
6969 tree res = DECL_RESULT (current_function_decl);
6970 tree inner;
6971
6972 current_function_returns_value = 1;
6973 if (t == error_mark_node)
6974 return NULL_TREE;
6975
6976 inner = t = convert (TREE_TYPE (res), t);
6977
6978 /* Strip any conversions, additions, and subtractions, and see if
6979 we are returning the address of a local variable. Warn if so. */
6980 while (1)
6981 {
6982 switch (TREE_CODE (inner))
6983 {
6984 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6985 case PLUS_EXPR:
6986 inner = TREE_OPERAND (inner, 0);
6987 continue;
6988
6989 case MINUS_EXPR:
6990 /* If the second operand of the MINUS_EXPR has a pointer
6991 type (or is converted from it), this may be valid, so
6992 don't give a warning. */
6993 {
6994 tree op1 = TREE_OPERAND (inner, 1);
6995
6996 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6997 && (TREE_CODE (op1) == NOP_EXPR
6998 || TREE_CODE (op1) == NON_LVALUE_EXPR
6999 || TREE_CODE (op1) == CONVERT_EXPR))
7000 op1 = TREE_OPERAND (op1, 0);
7001
7002 if (POINTER_TYPE_P (TREE_TYPE (op1)))
7003 break;
7004
7005 inner = TREE_OPERAND (inner, 0);
7006 continue;
7007 }
7008
7009 case ADDR_EXPR:
7010 inner = TREE_OPERAND (inner, 0);
7011
7012 while (REFERENCE_CLASS_P (inner)
7013 && TREE_CODE (inner) != INDIRECT_REF)
7014 inner = TREE_OPERAND (inner, 0);
7015
7016 if (DECL_P (inner)
7017 && !DECL_EXTERNAL (inner)
7018 && !TREE_STATIC (inner)
7019 && DECL_CONTEXT (inner) == current_function_decl)
7020 warning (0, "function returns address of local variable");
7021 break;
7022
7023 default:
7024 break;
7025 }
7026
7027 break;
7028 }
7029
7030 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
7031 }
7032
7033 ret_stmt = build_stmt (RETURN_EXPR, retval);
7034 TREE_NO_WARNING (ret_stmt) |= no_warning;
7035 return add_stmt (ret_stmt);
7036}
7037
7038struct c_switch {
7039 /* The SWITCH_EXPR being built. */
7040 tree switch_expr;
7041
7042 /* The original type of the testing expression, i.e. before the
7043 default conversion is applied. */
7044 tree orig_type;
7045
7046 /* A splay-tree mapping the low element of a case range to the high
7047 element, or NULL_TREE if there is no high element. Used to
7048 determine whether or not a new case label duplicates an old case
7049 label. We need a tree, rather than simply a hash table, because
7050 of the GNU case range extension. */
7051 splay_tree cases;
7052
7053 /* Number of nested statement expressions within this switch
7054 statement; if nonzero, case and default labels may not
7055 appear. */
7056 unsigned int blocked_stmt_expr;
7057
7058 /* Scope of outermost declarations of identifiers with variably
7059 modified type within this switch statement; if nonzero, case and
7060 default labels may not appear. */
7061 unsigned int blocked_vm;
7062
7063 /* The next node on the stack. */
7064 struct c_switch *next;
7065};
7066
7067/* A stack of the currently active switch statements. The innermost
7068 switch statement is on the top of the stack. There is no need to
7069 mark the stack for garbage collection because it is only active
7070 during the processing of the body of a function, and we never
7071 collect at that point. */
7072
7073struct c_switch *c_switch_stack;
7074
7075/* Start a C switch statement, testing expression EXP. Return the new
7076 SWITCH_EXPR. */
7077
7078tree
7079c_start_case (tree exp)
7080{
7081 tree orig_type = error_mark_node;
7082 struct c_switch *cs;
7083
7084 if (exp != error_mark_node)
7085 {
7086 orig_type = TREE_TYPE (exp);
7087
7088 if (!INTEGRAL_TYPE_P (orig_type))
7089 {
7090 if (orig_type != error_mark_node)
7091 {
7092 error ("switch quantity not an integer");
7093 orig_type = error_mark_node;
7094 }
7095 exp = integer_zero_node;
7096 }
7097 else
7098 {
7099 tree type = TYPE_MAIN_VARIANT (orig_type);
7100
7101 if (!in_system_header
7102 && (type == long_integer_type_node
7103 || type == long_unsigned_type_node))
7104 warning (OPT_Wtraditional, "%<long%> switch expression not "
7105 "converted to %<int%> in ISO C");
7106
7107 exp = default_conversion (exp);
7108 }
7109 }
7110
7111 /* Add this new SWITCH_EXPR to the stack. */
7112 cs = XNEW (struct c_switch);
7113 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
7114 cs->orig_type = orig_type;
7115 cs->cases = splay_tree_new (case_compare, NULL, NULL);
7116 cs->blocked_stmt_expr = 0;
7117 cs->blocked_vm = 0;
7118 cs->next = c_switch_stack;
7119 c_switch_stack = cs;
7120
7121 return add_stmt (cs->switch_expr);
7122}
7123
7124/* Process a case label. */
7125
7126tree
7127do_case (tree low_value, tree high_value)
7128{
7129 tree label = NULL_TREE;
7130
7131 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
7132 && !c_switch_stack->blocked_vm)
7133 {
7134 label = c_add_case_label (c_switch_stack->cases,
7135 SWITCH_COND (c_switch_stack->switch_expr),
7136 c_switch_stack->orig_type,
7137 low_value, high_value);
7138 if (label == error_mark_node)
7139 label = NULL_TREE;
7140 }
7141 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
7142 {
7143 if (low_value)
7144 error ("case label in statement expression not containing "
7145 "enclosing switch statement");
7146 else
7147 error ("%<default%> label in statement expression not containing "
7148 "enclosing switch statement");
7149 }
7150 else if (c_switch_stack && c_switch_stack->blocked_vm)
7151 {
7152 if (low_value)
7153 error ("case label in scope of identifier with variably modified "
7154 "type not containing enclosing switch statement");
7155 else
7156 error ("%<default%> label in scope of identifier with variably "
7157 "modified type not containing enclosing switch statement");
7158 }
7159 else if (low_value)
7160 error ("case label not within a switch statement");
7161 else
7162 error ("%<default%> label not within a switch statement");
7163
7164 return label;
7165}
7166
7167/* Finish the switch statement. */
7168
7169void
7170c_finish_case (tree body)
7171{
7172 struct c_switch *cs = c_switch_stack;
7173 location_t switch_location;
7174
7175 SWITCH_BODY (cs->switch_expr) = body;
7176
7177 /* We must not be within a statement expression nested in the switch
7178 at this point; we might, however, be within the scope of an
7179 identifier with variably modified type nested in the switch. */
7180 gcc_assert (!cs->blocked_stmt_expr);
7181
7182 /* Emit warnings as needed. */
7183 if (EXPR_HAS_LOCATION (cs->switch_expr))
7184 switch_location = EXPR_LOCATION (cs->switch_expr);
7185 else
7186 switch_location = input_location;
7187 c_do_switch_warnings (cs->cases, switch_location,
7188 TREE_TYPE (cs->switch_expr),
7189 SWITCH_COND (cs->switch_expr));
7190
7191 /* Pop the stack. */
7192 c_switch_stack = cs->next;
7193 splay_tree_delete (cs->cases);
7194 XDELETE (cs);
7195}
7196
7197/* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
7198 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
7199 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
7200 statement, and was not surrounded with parenthesis. */
7201
7202void
7203c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
7204 tree else_block, bool nested_if)
7205{
7206 tree stmt;
7207
7208 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
7209 if (warn_parentheses && nested_if && else_block == NULL)
7210 {
7211 tree inner_if = then_block;
7212
7213 /* We know from the grammar productions that there is an IF nested
7214 within THEN_BLOCK. Due to labels and c99 conditional declarations,
7215 it might not be exactly THEN_BLOCK, but should be the last
7216 non-container statement within. */
7217 while (1)
7218 switch (TREE_CODE (inner_if))
7219 {
7220 case COND_EXPR:
7221 goto found;
7222 case BIND_EXPR:
7223 inner_if = BIND_EXPR_BODY (inner_if);
7224 break;
7225 case STATEMENT_LIST:
7226 inner_if = expr_last (then_block);
7227 break;
7228 case TRY_FINALLY_EXPR:
7229 case TRY_CATCH_EXPR:
7230 inner_if = TREE_OPERAND (inner_if, 0);
7231 break;
7232 default:
7233 gcc_unreachable ();
7234 }
7235 found:
7236
7237 if (COND_EXPR_ELSE (inner_if))
7238 warning (OPT_Wparentheses,
7239 "%Hsuggest explicit braces to avoid ambiguous %<else%>",
7240 &if_locus);
7241 }
7242
7243 empty_body_warning (then_block, else_block);
7244
7245 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
7246 SET_EXPR_LOCATION (stmt, if_locus);
7247 add_stmt (stmt);
7248}
7249
7250/* Emit a general-purpose loop construct. START_LOCUS is the location of
7251 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
7252 is false for DO loops. INCR is the FOR increment expression. BODY is
7253 the statement controlled by the loop. BLAB is the break label. CLAB is
7254 the continue label. Everything is allowed to be NULL. */
7255
7256void
7257c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
7258 tree blab, tree clab, bool cond_is_first)
7259{
7260 tree entry = NULL, exit = NULL, t;
7261
7262 /* If the condition is zero don't generate a loop construct. */
7263 if (cond && integer_zerop (cond))
7264 {
7265 if (cond_is_first)
7266 {
7267 t = build_and_jump (&blab);
7268 SET_EXPR_LOCATION (t, start_locus);
7269 add_stmt (t);
7270 }
7271 }
7272 else
7273 {
7274 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7275
7276 /* If we have an exit condition, then we build an IF with gotos either
7277 out of the loop, or to the top of it. If there's no exit condition,
7278 then we just build a jump back to the top. */
7279 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
7280
7281 if (cond && !integer_nonzerop (cond))
7282 {
7283 /* Canonicalize the loop condition to the end. This means
7284 generating a branch to the loop condition. Reuse the
7285 continue label, if possible. */
7286 if (cond_is_first)
7287 {
7288 if (incr || !clab)
7289 {
7290 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7291 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
7292 }
7293 else
7294 t = build1 (GOTO_EXPR, void_type_node, clab);
7295 SET_EXPR_LOCATION (t, start_locus);
7296 add_stmt (t);
7297 }
7298
7299 t = build_and_jump (&blab);
7300 exit = fold_build3 (COND_EXPR, void_type_node, cond, exit, t);
7301 if (cond_is_first)
7302 SET_EXPR_LOCATION (exit, start_locus);
7303 else
7304 SET_EXPR_LOCATION (exit, input_location);
7305 }
7306
7307 add_stmt (top);
7308 }
7309
7310 if (body)
7311 add_stmt (body);
7312 if (clab)
7313 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
7314 if (incr)
7315 add_stmt (incr);
7316 if (entry)
7317 add_stmt (entry);
7318 if (exit)
7319 add_stmt (exit);
7320 if (blab)
7321 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7322}
7323
7324tree
7325c_finish_bc_stmt (tree *label_p, bool is_break)
7326{
7327 bool skip;
7328 tree label = *label_p;
7329
7330 /* In switch statements break is sometimes stylistically used after
7331 a return statement. This can lead to spurious warnings about
7332 control reaching the end of a non-void function when it is
7333 inlined. Note that we are calling block_may_fallthru with
7334 language specific tree nodes; this works because
7335 block_may_fallthru returns true when given something it does not
7336 understand. */
7337 skip = !block_may_fallthru (cur_stmt_list);
7338
7339 if (!label)
7340 {
7341 if (!skip)
7342 *label_p = label = create_artificial_label ();
7343 }
7344 else if (TREE_CODE (label) == LABEL_DECL)
7345 ;
7346 else switch (TREE_INT_CST_LOW (label))
7347 {
7348 case 0:
7349 if (is_break)
7350 error ("break statement not within loop or switch");
7351 else
7352 error ("continue statement not within a loop");
7353 return NULL_TREE;
7354
7355 case 1:
7356 gcc_assert (is_break);
7357 error ("break statement used with OpenMP for loop");
7358 return NULL_TREE;
7359
7360 default:
7361 gcc_unreachable ();
7362 }
7363
7364 if (skip)
7365 return NULL_TREE;
7366
7367 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7368}
7369
7370/* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7371
7372static void
7373emit_side_effect_warnings (tree expr)
7374{
7375 if (expr == error_mark_node)
7376 ;
7377 else if (!TREE_SIDE_EFFECTS (expr))
7378 {
7379 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7380 warning (0, "%Hstatement with no effect",
7381 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7382 }
7383 else if (warn_unused_value)
7384 warn_if_unused_value (expr, input_location);
7385}
7386
7387/* Process an expression as if it were a complete statement. Emit
7388 diagnostics, but do not call ADD_STMT. */
7389
7390tree
7391c_process_expr_stmt (tree expr)
7392{
7393 if (!expr)
7394 return NULL_TREE;
7395
7396 if (warn_sequence_point)
7397 verify_sequence_points (expr);
7398
7399 if (TREE_TYPE (expr) != error_mark_node
7400 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7401 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7402 error ("expression statement has incomplete type");
7403
7404 /* If we're not processing a statement expression, warn about unused values.
7405 Warnings for statement expressions will be emitted later, once we figure
7406 out which is the result. */
7407 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7408 && (extra_warnings || warn_unused_value))
7409 emit_side_effect_warnings (expr);
7410
7411 /* If the expression is not of a type to which we cannot assign a line
7412 number, wrap the thing in a no-op NOP_EXPR. */
7413 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7414 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7415
7416 if (EXPR_P (expr))
7417 SET_EXPR_LOCATION (expr, input_location);
7418
7419 return expr;
7420}
7421
7422/* Emit an expression as a statement. */
7423
7424tree
7425c_finish_expr_stmt (tree expr)
7426{
7427 if (expr)
7428 return add_stmt (c_process_expr_stmt (expr));
7429 else
7430 return NULL;
7431}
7432
7433/* Do the opposite and emit a statement as an expression. To begin,
7434 create a new binding level and return it. */
7435
7436tree
7437c_begin_stmt_expr (void)
7438{
7439 tree ret;
7440 struct c_label_context_se *nstack;
7441 struct c_label_list *glist;
7442
7443 /* We must force a BLOCK for this level so that, if it is not expanded
7444 later, there is a way to turn off the entire subtree of blocks that
7445 are contained in it. */
7446 keep_next_level ();
7447 ret = c_begin_compound_stmt (true);
7448 if (c_switch_stack)
7449 {
7450 c_switch_stack->blocked_stmt_expr++;
7451 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7452 }
7453 for (glist = label_context_stack_se->labels_used;
7454 glist != NULL;
7455 glist = glist->next)
7456 {
7457 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7458 }
7459 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7460 nstack->labels_def = NULL;
7461 nstack->labels_used = NULL;
7462 nstack->next = label_context_stack_se;
7463 label_context_stack_se = nstack;
7464
7465 /* Mark the current statement list as belonging to a statement list. */
7466 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7467
7468 return ret;
7469}
7470
7471tree
7472c_finish_stmt_expr (tree body)
7473{
7474 tree last, type, tmp, val;
7475 tree *last_p;
7476 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7477
7478 body = c_end_compound_stmt (body, true);
7479 if (c_switch_stack)
7480 {
7481 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7482 c_switch_stack->blocked_stmt_expr--;
7483 }
7484 /* It is no longer possible to jump to labels defined within this
7485 statement expression. */
7486 for (dlist = label_context_stack_se->labels_def;
7487 dlist != NULL;
7488 dlist = dlist->next)
7489 {
7490 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7491 }
7492 /* It is again possible to define labels with a goto just outside
7493 this statement expression. */
7494 for (glist = label_context_stack_se->next->labels_used;
7495 glist != NULL;
7496 glist = glist->next)
7497 {
7498 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7499 glist_prev = glist;
7500 }
7501 if (glist_prev != NULL)
7502 glist_prev->next = label_context_stack_se->labels_used;
7503 else
7504 label_context_stack_se->next->labels_used
7505 = label_context_stack_se->labels_used;
7506 label_context_stack_se = label_context_stack_se->next;
7507
7508 /* Locate the last statement in BODY. See c_end_compound_stmt
7509 about always returning a BIND_EXPR. */
7510 last_p = &BIND_EXPR_BODY (body);
7511 last = BIND_EXPR_BODY (body);
7512
7513 continue_searching:
7514 if (TREE_CODE (last) == STATEMENT_LIST)
7515 {
7516 tree_stmt_iterator i;
7517
7518 /* This can happen with degenerate cases like ({ }). No value. */
7519 if (!TREE_SIDE_EFFECTS (last))
7520 return body;
7521
7522 /* If we're supposed to generate side effects warnings, process
7523 all of the statements except the last. */
7524 if (extra_warnings || warn_unused_value)
7525 {
7526 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7527 emit_side_effect_warnings (tsi_stmt (i));
7528 }
7529 else
7530 i = tsi_last (last);
7531 last_p = tsi_stmt_ptr (i);
7532 last = *last_p;
7533 }
7534
7535 /* If the end of the list is exception related, then the list was split
7536 by a call to push_cleanup. Continue searching. */
7537 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7538 || TREE_CODE (last) == TRY_CATCH_EXPR)
7539 {
7540 last_p = &TREE_OPERAND (last, 0);
7541 last = *last_p;
7542 goto continue_searching;
7543 }
7544
7545 /* In the case that the BIND_EXPR is not necessary, return the
7546 expression out from inside it. */
7547 if (last == error_mark_node
7548 || (last == BIND_EXPR_BODY (body)
7549 && BIND_EXPR_VARS (body) == NULL))
7550 {
7551 /* Do not warn if the return value of a statement expression is
7552 unused. */
7553 if (EXPR_P (last))
7554 TREE_NO_WARNING (last) = 1;
7555 return last;
7556 }
7557
7558 /* Extract the type of said expression. */
7559 type = TREE_TYPE (last);
7560
7561 /* If we're not returning a value at all, then the BIND_EXPR that
7562 we already have is a fine expression to return. */
7563 if (!type || VOID_TYPE_P (type))
7564 return body;
7565
7566 /* Now that we've located the expression containing the value, it seems
7567 silly to make voidify_wrapper_expr repeat the process. Create a
7568 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7569 tmp = create_tmp_var_raw (type, NULL);
7570
7571 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7572 tree_expr_nonnegative_p giving up immediately. */
7573 val = last;
7574 if (TREE_CODE (val) == NOP_EXPR
7575 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7576 val = TREE_OPERAND (val, 0);
7577
7578 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7579 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7580
7581 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7582}
7583
7584/* Begin the scope of an identifier of variably modified type, scope
7585 number SCOPE. Jumping from outside this scope to inside it is not
7586 permitted. */
7587
7588void
7589c_begin_vm_scope (unsigned int scope)
7590{
7591 struct c_label_context_vm *nstack;
7592 struct c_label_list *glist;
7593
7594 gcc_assert (scope > 0);
7595
7596 /* At file_scope, we don't have to do any processing. */
7597 if (label_context_stack_vm == NULL)
7598 return;
7599
7600 if (c_switch_stack && !c_switch_stack->blocked_vm)
7601 c_switch_stack->blocked_vm = scope;
7602 for (glist = label_context_stack_vm->labels_used;
7603 glist != NULL;
7604 glist = glist->next)
7605 {
7606 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7607 }
7608 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7609 nstack->labels_def = NULL;
7610 nstack->labels_used = NULL;
7611 nstack->scope = scope;
7612 nstack->next = label_context_stack_vm;
7613 label_context_stack_vm = nstack;
7614}
7615
7616/* End a scope which may contain identifiers of variably modified
7617 type, scope number SCOPE. */
7618
7619void
7620c_end_vm_scope (unsigned int scope)
7621{
7622 if (label_context_stack_vm == NULL)
7623 return;
7624 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7625 c_switch_stack->blocked_vm = 0;
7626 /* We may have a number of nested scopes of identifiers with
7627 variably modified type, all at this depth. Pop each in turn. */
7628 while (label_context_stack_vm->scope == scope)
7629 {
7630 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7631
7632 /* It is no longer possible to jump to labels defined within this
7633 scope. */
7634 for (dlist = label_context_stack_vm->labels_def;
7635 dlist != NULL;
7636 dlist = dlist->next)
7637 {
7638 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7639 }
7640 /* It is again possible to define labels with a goto just outside
7641 this scope. */
7642 for (glist = label_context_stack_vm->next->labels_used;
7643 glist != NULL;
7644 glist = glist->next)
7645 {
7646 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7647 glist_prev = glist;
7648 }
7649 if (glist_prev != NULL)
7650 glist_prev->next = label_context_stack_vm->labels_used;
7651 else
7652 label_context_stack_vm->next->labels_used
7653 = label_context_stack_vm->labels_used;
7654 label_context_stack_vm = label_context_stack_vm->next;
7655 }
7656}
7657
7658/* Begin and end compound statements. This is as simple as pushing
7659 and popping new statement lists from the tree. */
7660
7661tree
7662c_begin_compound_stmt (bool do_scope)
7663{
7664 tree stmt = push_stmt_list ();
7665 if (do_scope)
7666 push_scope ();
7667 return stmt;
7668}
7669
7670tree
7671c_end_compound_stmt (tree stmt, bool do_scope)
7672{
7673 tree block = NULL;
7674
7675 if (do_scope)
7676 {
7677 if (c_dialect_objc ())
7678 objc_clear_super_receiver ();
7679 block = pop_scope ();
7680 }
7681
7682 stmt = pop_stmt_list (stmt);
7683 stmt = c_build_bind_expr (block, stmt);
7684
7685 /* If this compound statement is nested immediately inside a statement
7686 expression, then force a BIND_EXPR to be created. Otherwise we'll
7687 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7688 STATEMENT_LISTs merge, and thus we can lose track of what statement
7689 was really last. */
7690 if (cur_stmt_list
7691 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7692 && TREE_CODE (stmt) != BIND_EXPR)
7693 {
7694 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7695 TREE_SIDE_EFFECTS (stmt) = 1;
7696 }
7697
7698 return stmt;
7699}
7700
7701/* Queue a cleanup. CLEANUP is an expression/statement to be executed
7702 when the current scope is exited. EH_ONLY is true when this is not
7703 meant to apply to normal control flow transfer. */
7704
7705void
7706push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7707{
7708 enum tree_code code;
7709 tree stmt, list;
7710 bool stmt_expr;
7711
7712 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7713 stmt = build_stmt (code, NULL, cleanup);
7714 add_stmt (stmt);
7715 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7716 list = push_stmt_list ();
7717 TREE_OPERAND (stmt, 0) = list;
7718 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7719}
7720
7721/* Build a binary-operation expression without default conversions.
7722 CODE is the kind of expression to build.
7723 This function differs from `build' in several ways:
7724 the data type of the result is computed and recorded in it,
7725 warnings are generated if arg data types are invalid,
7726 special handling for addition and subtraction of pointers is known,
7727 and some optimization is done (operations on narrow ints
7728 are done in the narrower type when that gives the same result).
7729 Constant folding is also done before the result is returned.
7730
7731 Note that the operands will never have enumeral types, or function
7732 or array types, because either they will have the default conversions
7733 performed or they have both just been converted to some other type in which
7734 the arithmetic is to be done. */
7735
7736tree
7737build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7738 int convert_p)
7739{
7740 tree type0, type1;
7741 enum tree_code code0, code1;
7742 tree op0, op1;
7743 const char *invalid_op_diag;
7744
7745 /* Expression code to give to the expression when it is built.
7746 Normally this is CODE, which is what the caller asked for,
7747 but in some special cases we change it. */
7748 enum tree_code resultcode = code;
7749
7750 /* Data type in which the computation is to be performed.
7751 In the simplest cases this is the common type of the arguments. */
7752 tree result_type = NULL;
7753
7754 /* Nonzero means operands have already been type-converted
7755 in whatever way is necessary.
7756 Zero means they need to be converted to RESULT_TYPE. */
7757 int converted = 0;
7758
7759 /* Nonzero means create the expression with this type, rather than
7760 RESULT_TYPE. */
7761 tree build_type = 0;
7762
7763 /* Nonzero means after finally constructing the expression
7764 convert it to this type. */
7765 tree final_type = 0;
7766
7767 /* Nonzero if this is an operation like MIN or MAX which can
7768 safely be computed in short if both args are promoted shorts.
7769 Also implies COMMON.
7770 -1 indicates a bitwise operation; this makes a difference
7771 in the exact conditions for when it is safe to do the operation
7772 in a narrower mode. */
7773 int shorten = 0;
7774
7775 /* Nonzero if this is a comparison operation;
7776 if both args are promoted shorts, compare the original shorts.
7777 Also implies COMMON. */
7778 int short_compare = 0;
7779
7780 /* Nonzero if this is a right-shift operation, which can be computed on the
7781 original short and then promoted if the operand is a promoted short. */
7782 int short_shift = 0;
7783
7784 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7785 int common = 0;
7786
7787 /* True means types are compatible as far as ObjC is concerned. */
7788 bool objc_ok;
7789
7790 if (convert_p)
7791 {
7792 op0 = default_conversion (orig_op0);
7793 op1 = default_conversion (orig_op1);
7794 }
7795 else
7796 {
7797 op0 = orig_op0;
7798 op1 = orig_op1;
7799 }
7800
7801 type0 = TREE_TYPE (op0);
7802 type1 = TREE_TYPE (op1);
7803
7804 /* The expression codes of the data types of the arguments tell us
7805 whether the arguments are integers, floating, pointers, etc. */
7806 code0 = TREE_CODE (type0);
7807 code1 = TREE_CODE (type1);
7808
7809 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7810 STRIP_TYPE_NOPS (op0);
7811 STRIP_TYPE_NOPS (op1);
7812
7813 /* If an error was already reported for one of the arguments,
7814 avoid reporting another error. */
7815
7816 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7817 return error_mark_node;
7818
7819 if ((invalid_op_diag
7820 = targetm.invalid_binary_op (code, type0, type1)))
7821 {
7822 error (invalid_op_diag, "");
7823 return error_mark_node;
7824 }
7825
7826 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
7827
7828 switch (code)
7829 {
7830 case PLUS_EXPR:
7831 /* Handle the pointer + int case. */
7832 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7833 return pointer_int_sum (PLUS_EXPR, op0, op1);
7834 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7835 return pointer_int_sum (PLUS_EXPR, op1, op0);
7836 else
7837 common = 1;
7838 break;
7839
7840 case MINUS_EXPR:
7841 /* Subtraction of two similar pointers.
7842 We must subtract them as integers, then divide by object size. */
7843 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7844 && comp_target_types (type0, type1))
7845 return pointer_diff (op0, op1);
7846 /* Handle pointer minus int. Just like pointer plus int. */
7847 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7848 return pointer_int_sum (MINUS_EXPR, op0, op1);
7849 else
7850 common = 1;
7851 break;
7852
7853 case MULT_EXPR:
7854 common = 1;
7855 break;
7856
7857 case TRUNC_DIV_EXPR:
7858 case CEIL_DIV_EXPR:
7859 case FLOOR_DIV_EXPR:
7860 case ROUND_DIV_EXPR:
7861 case EXACT_DIV_EXPR:
7862 /* Floating point division by zero is a legitimate way to obtain
7863 infinities and NaNs. */
7864 if (skip_evaluation == 0 && integer_zerop (op1))
7865 warning (OPT_Wdiv_by_zero, "division by zero");
7866
7867 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7868 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7869 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7870 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7871 {
7872 enum tree_code tcode0 = code0, tcode1 = code1;
7873
7874 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7875 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7876 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7877 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7878
7879 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
7880 resultcode = RDIV_EXPR;
7881 else
7882 /* Although it would be tempting to shorten always here, that
7883 loses on some targets, since the modulo instruction is
7884 undefined if the quotient can't be represented in the
7885 computation mode. We shorten only if unsigned or if
7886 dividing by something we know != -1. */
7887 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7888 || (TREE_CODE (op1) == INTEGER_CST
7889 && !integer_all_onesp (op1)));
7890 common = 1;
7891 }
7892 break;
7893
7894 case BIT_AND_EXPR:
7895 case BIT_IOR_EXPR:
7896 case BIT_XOR_EXPR:
7897 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7898 shorten = -1;
7899 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7900 common = 1;
7901 break;
7902
7903 case TRUNC_MOD_EXPR:
7904 case FLOOR_MOD_EXPR:
7905 if (skip_evaluation == 0 && integer_zerop (op1))
7906 warning (OPT_Wdiv_by_zero, "division by zero");
7907
7908 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7909 {
7910 /* Although it would be tempting to shorten always here, that loses
7911 on some targets, since the modulo instruction is undefined if the
7912 quotient can't be represented in the computation mode. We shorten
7913 only if unsigned or if dividing by something we know != -1. */
7914 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7915 || (TREE_CODE (op1) == INTEGER_CST
7916 && !integer_all_onesp (op1)));
7917 common = 1;
7918 }
7919 break;
7920
7921 case TRUTH_ANDIF_EXPR:
7922 case TRUTH_ORIF_EXPR:
7923 case TRUTH_AND_EXPR:
7924 case TRUTH_OR_EXPR:
7925 case TRUTH_XOR_EXPR:
7926 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7927 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7928 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7929 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7930 {
7931 /* Result of these operations is always an int,
7932 but that does not mean the operands should be
7933 converted to ints! */
7934 result_type = integer_type_node;
7935 op0 = c_common_truthvalue_conversion (op0);
7936 op1 = c_common_truthvalue_conversion (op1);
7937 converted = 1;
7938 }
7939 break;
7940
7941 /* Shift operations: result has same type as first operand;
7942 always convert second operand to int.
7943 Also set SHORT_SHIFT if shifting rightward. */
7944
7945 case RSHIFT_EXPR:
7946 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7947 {
7948 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7949 {
7950 if (tree_int_cst_sgn (op1) < 0)
7951 warning (0, "right shift count is negative");
7952 else
7953 {
7954 if (!integer_zerop (op1))
7955 short_shift = 1;
7956
7957 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7958 warning (0, "right shift count >= width of type");
7959 }
7960 }
7961
7962 /* Use the type of the value to be shifted. */
7963 result_type = type0;
7964 /* Convert the shift-count to an integer, regardless of size
7965 of value being shifted. */
7966 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7967 op1 = convert (integer_type_node, op1);
7968 /* Avoid converting op1 to result_type later. */
7969 converted = 1;
7970 }
7971 break;
7972
7973 case LSHIFT_EXPR:
7974 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7975 {
7976 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7977 {
7978 if (tree_int_cst_sgn (op1) < 0)
7979 warning (0, "left shift count is negative");
7980
7981 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7982 warning (0, "left shift count >= width of type");
7983 }
7984
7985 /* Use the type of the value to be shifted. */
7986 result_type = type0;
7987 /* Convert the shift-count to an integer, regardless of size
7988 of value being shifted. */
7989 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7990 op1 = convert (integer_type_node, op1);
7991 /* Avoid converting op1 to result_type later. */
7992 converted = 1;
7993 }
7994 break;
7995
7996 case EQ_EXPR:
7997 case NE_EXPR:
7998 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
7999 warning (OPT_Wfloat_equal,
8000 "comparing floating point with == or != is unsafe");
8001 /* Result of comparison is always int,
8002 but don't convert the args to int! */
8003 build_type = integer_type_node;
8004 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
8005 || code0 == COMPLEX_TYPE)
8006 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
8007 || code1 == COMPLEX_TYPE))
8008 short_compare = 1;
8009 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8010 {
8011 tree tt0 = TREE_TYPE (type0);
8012 tree tt1 = TREE_TYPE (type1);
8013 /* Anything compares with void *. void * compares with anything.
8014 Otherwise, the targets must be compatible
8015 and both must be object or both incomplete. */
8016 if (comp_target_types (type0, type1))
8017 result_type = common_pointer_type (type0, type1);
8018 else if (VOID_TYPE_P (tt0))
8019 {
8020 /* op0 != orig_op0 detects the case of something
8021 whose value is 0 but which isn't a valid null ptr const. */
8022 if (pedantic && !null_pointer_constant_p (orig_op0)
8023 && TREE_CODE (tt1) == FUNCTION_TYPE)
8024 pedwarn ("ISO C forbids comparison of %<void *%>"
8025 " with function pointer");
8026 }
8027 else if (VOID_TYPE_P (tt1))
8028 {
8029 if (pedantic && !null_pointer_constant_p (orig_op1)
8030 && TREE_CODE (tt0) == FUNCTION_TYPE)
8031 pedwarn ("ISO C forbids comparison of %<void *%>"
8032 " with function pointer");
8033 }
8034 else
8035 /* Avoid warning about the volatile ObjC EH puts on decls. */
8036 if (!objc_ok)
8037 pedwarn ("comparison of distinct pointer types lacks a cast");
8038
8039 if (result_type == NULL_TREE)
8040 result_type = ptr_type_node;
8041 }
8042 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8043 {
8044 if (TREE_CODE (op0) == ADDR_EXPR
8045 && DECL_P (TREE_OPERAND (op0, 0))
8046 && (TREE_CODE (TREE_OPERAND (op0, 0)) == PARM_DECL
8047 || TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL
8048 || !DECL_WEAK (TREE_OPERAND (op0, 0))))
8049 warning (OPT_Waddress, "the address of %qD will never be NULL",
8050 TREE_OPERAND (op0, 0));
8051 result_type = type0;
8052 }
8053 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8054 {
8055 if (TREE_CODE (op1) == ADDR_EXPR
8056 && DECL_P (TREE_OPERAND (op1, 0))
8057 && (TREE_CODE (TREE_OPERAND (op1, 0)) == PARM_DECL
8058 || TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL
8059 || !DECL_WEAK (TREE_OPERAND (op1, 0))))
8060 warning (OPT_Waddress, "the address of %qD will never be NULL",
8061 TREE_OPERAND (op1, 0));
8062 result_type = type1;
8063 }
8064 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8065 {
8066 result_type = type0;
8067 pedwarn ("comparison between pointer and integer");
8068 }
8069 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8070 {
8071 result_type = type1;
8072 pedwarn ("comparison between pointer and integer");
8073 }
8074 break;
8075
8076 case LE_EXPR:
8077 case GE_EXPR:
8078 case LT_EXPR:
8079 case GT_EXPR:
8080 build_type = integer_type_node;
8081 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
8082 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
8083 short_compare = 1;
8084 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8085 {
8086 if (comp_target_types (type0, type1))
8087 {
8088 result_type = common_pointer_type (type0, type1);
8089 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
8090 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
8091 pedwarn ("comparison of complete and incomplete pointers");
8092 else if (pedantic
8093 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
8094 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
8095 }
8096 else
8097 {
8098 result_type = ptr_type_node;
8099 pedwarn ("comparison of distinct pointer types lacks a cast");
8100 }
8101 }
8102 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8103 {
8104 result_type = type0;
8105 if (pedantic || extra_warnings)
8106 pedwarn ("ordered comparison of pointer with integer zero");
8107 }
8108 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8109 {
8110 result_type = type1;
8111 if (pedantic)
8112 pedwarn ("ordered comparison of pointer with integer zero");
8113 }
8114 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8115 {
8116 result_type = type0;
8117 pedwarn ("comparison between pointer and integer");
8118 }
8119 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8120 {
8121 result_type = type1;
8122 pedwarn ("comparison between pointer and integer");
8123 }
8124 break;
8125
8126 default:
8127 gcc_unreachable ();
8128 }
8129
8130 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
8131 return error_mark_node;
8132
8133 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
8134 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
8135 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
8136 TREE_TYPE (type1))))
8137 {
8138 binary_op_error (code, type0, type1);
8139 return error_mark_node;
8140 }
8141
8142 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
8143 || code0 == VECTOR_TYPE)
8144 &&
8145 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
8146 || code1 == VECTOR_TYPE))
8147 {
8148 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
8149
8150 if (shorten || common || short_compare)
8151 result_type = c_common_type (type0, type1);
8152
8153 /* For certain operations (which identify themselves by shorten != 0)
8154 if both args were extended from the same smaller type,
8155 do the arithmetic in that type and then extend.
8156
8157 shorten !=0 and !=1 indicates a bitwise operation.
8158 For them, this optimization is safe only if
8159 both args are zero-extended or both are sign-extended.
8160 Otherwise, we might change the result.
8161 Eg, (short)-1 | (unsigned short)-1 is (int)-1
8162 but calculated in (unsigned short) it would be (unsigned short)-1. */
8163
8164 if (shorten && none_complex)
8165 {
8166 int unsigned0, unsigned1;
8167 tree arg0, arg1;
8168 int uns;
8169 tree type;
8170
8171 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents
8172 excessive narrowing when we call get_narrower below. For
8173 example, suppose that OP0 is of unsigned int extended
8174 from signed char and that RESULT_TYPE is long long int.
8175 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
8176 like
8177
8178 (long long int) (unsigned int) signed_char
8179
8180 which get_narrower would narrow down to
8181
8182 (unsigned int) signed char
8183
8184 If we do not cast OP0 first, get_narrower would return
8185 signed_char, which is inconsistent with the case of the
8186 explicit cast. */
8187 op0 = convert (result_type, op0);
8188 op1 = convert (result_type, op1);
8189
8190 arg0 = get_narrower (op0, &unsigned0);
8191 arg1 = get_narrower (op1, &unsigned1);
8192
8193 /* UNS is 1 if the operation to be done is an unsigned one. */
8194 uns = TYPE_UNSIGNED (result_type);
8195
8196 final_type = result_type;
8197
8198 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
8199 but it *requires* conversion to FINAL_TYPE. */
8200
8201 if ((TYPE_PRECISION (TREE_TYPE (op0))
8202 == TYPE_PRECISION (TREE_TYPE (arg0)))
8203 && TREE_TYPE (op0) != final_type)
8204 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
8205 if ((TYPE_PRECISION (TREE_TYPE (op1))
8206 == TYPE_PRECISION (TREE_TYPE (arg1)))
8207 && TREE_TYPE (op1) != final_type)
8208 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
8209
8210 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
8211
8212 /* For bitwise operations, signedness of nominal type
8213 does not matter. Consider only how operands were extended. */
8214 if (shorten == -1)
8215 uns = unsigned0;
8216
8217 /* Note that in all three cases below we refrain from optimizing
8218 an unsigned operation on sign-extended args.
8219 That would not be valid. */
8220
8221 /* Both args variable: if both extended in same way
8222 from same width, do it in that width.
8223 Do it unsigned if args were zero-extended. */
8224 if ((TYPE_PRECISION (TREE_TYPE (arg0))
8225 < TYPE_PRECISION (result_type))
8226 && (TYPE_PRECISION (TREE_TYPE (arg1))
8227 == TYPE_PRECISION (TREE_TYPE (arg0)))
8228 && unsigned0 == unsigned1
8229 && (unsigned0 || !uns))
8230 result_type
8231 = c_common_signed_or_unsigned_type
8232 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
8233 else if (TREE_CODE (arg0) == INTEGER_CST
8234 && (unsigned1 || !uns)
8235 && (TYPE_PRECISION (TREE_TYPE (arg1))
8236 < TYPE_PRECISION (result_type))
8237 && (type
8238 = c_common_signed_or_unsigned_type (unsigned1,
8239 TREE_TYPE (arg1)),
8240 int_fits_type_p (arg0, type)))
8241 result_type = type;
8242 else if (TREE_CODE (arg1) == INTEGER_CST
8243 && (unsigned0 || !uns)
8244 && (TYPE_PRECISION (TREE_TYPE (arg0))
8245 < TYPE_PRECISION (result_type))
8246 && (type
8247 = c_common_signed_or_unsigned_type (unsigned0,
8248 TREE_TYPE (arg0)),
8249 int_fits_type_p (arg1, type)))
8250 result_type = type;
8251 }
8252
8253 /* Shifts can be shortened if shifting right. */
8254
8255 if (short_shift)
8256 {
8257 int unsigned_arg;
8258 tree arg0 = get_narrower (op0, &unsigned_arg);
8259
8260 final_type = result_type;
8261
8262 if (arg0 == op0 && final_type == TREE_TYPE (op0))
8263 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
8264
8265 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
8266 /* We can shorten only if the shift count is less than the
8267 number of bits in the smaller type size. */
8268 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
8269 /* We cannot drop an unsigned shift after sign-extension. */
8270 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
8271 {
8272 /* Do an unsigned shift if the operand was zero-extended. */
8273 result_type
8274 = c_common_signed_or_unsigned_type (unsigned_arg,
8275 TREE_TYPE (arg0));
8276 /* Convert value-to-be-shifted to that type. */
8277 if (TREE_TYPE (op0) != result_type)
8278 op0 = convert (result_type, op0);
8279 converted = 1;
8280 }
8281 }
8282
8283 /* Comparison operations are shortened too but differently.
8284 They identify themselves by setting short_compare = 1. */
8285
8286 if (short_compare)
8287 {
8288 /* Don't write &op0, etc., because that would prevent op0
8289 from being kept in a register.
8290 Instead, make copies of the our local variables and
8291 pass the copies by reference, then copy them back afterward. */
8292 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
8293 enum tree_code xresultcode = resultcode;
8294 tree val
8295 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
8296
8297 if (val != 0)
8298 return val;
8299
8300 op0 = xop0, op1 = xop1;
8301 converted = 1;
8302 resultcode = xresultcode;
8303
8304 if (warn_sign_compare && skip_evaluation == 0)
8305 {
8306 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
8307 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
8308 int unsignedp0, unsignedp1;
8309 tree primop0 = get_narrower (op0, &unsignedp0);
8310 tree primop1 = get_narrower (op1, &unsignedp1);
8311
8312 xop0 = orig_op0;
8313 xop1 = orig_op1;
8314 STRIP_TYPE_NOPS (xop0);
8315 STRIP_TYPE_NOPS (xop1);
8316
8317 /* Give warnings for comparisons between signed and unsigned
8318 quantities that may fail.
8319
8320 Do the checking based on the original operand trees, so that
8321 casts will be considered, but default promotions won't be.
8322
8323 Do not warn if the comparison is being done in a signed type,
8324 since the signed type will only be chosen if it can represent
8325 all the values of the unsigned type. */
8326 if (!TYPE_UNSIGNED (result_type))
8327 /* OK */;
8328 /* Do not warn if both operands are the same signedness. */
8329 else if (op0_signed == op1_signed)
8330 /* OK */;
8331 else
8332 {
8333 tree sop, uop;
8334 bool ovf;
8335
8336 if (op0_signed)
8337 sop = xop0, uop = xop1;
8338 else
8339 sop = xop1, uop = xop0;
8340
8341 /* Do not warn if the signed quantity is an
8342 unsuffixed integer literal (or some static
8343 constant expression involving such literals or a
8344 conditional expression involving such literals)
8345 and it is non-negative. */
8346 if (tree_expr_nonnegative_warnv_p (sop, &ovf))
8347 /* OK */;
8348 /* Do not warn if the comparison is an equality operation,
8349 the unsigned quantity is an integral constant, and it
8350 would fit in the result if the result were signed. */
8351 else if (TREE_CODE (uop) == INTEGER_CST
8352 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
8353 && int_fits_type_p
8354 (uop, c_common_signed_type (result_type)))
8355 /* OK */;
8356 /* Do not warn if the unsigned quantity is an enumeration
8357 constant and its maximum value would fit in the result
8358 if the result were signed. */
8359 else if (TREE_CODE (uop) == INTEGER_CST
8360 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
8361 && int_fits_type_p
8362 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
8363 c_common_signed_type (result_type)))
8364 /* OK */;
8365 else
8366 warning (0, "comparison between signed and unsigned");
8367 }
8368
8369 /* Warn if two unsigned values are being compared in a size
8370 larger than their original size, and one (and only one) is the
8371 result of a `~' operator. This comparison will always fail.
8372
8373 Also warn if one operand is a constant, and the constant
8374 does not have all bits set that are set in the ~ operand
8375 when it is extended. */
8376
8377 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
8378 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
8379 {
8380 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
8381 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
8382 &unsignedp0);
8383 else
8384 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
8385 &unsignedp1);
8386
8387 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
8388 {
8389 tree primop;
8390 HOST_WIDE_INT constant, mask;
8391 int unsignedp, bits;
8392
8393 if (host_integerp (primop0, 0))
8394 {
8395 primop = primop1;
8396 unsignedp = unsignedp1;
8397 constant = tree_low_cst (primop0, 0);
8398 }
8399 else
8400 {
8401 primop = primop0;
8402 unsignedp = unsignedp0;
8403 constant = tree_low_cst (primop1, 0);
8404 }
8405
8406 bits = TYPE_PRECISION (TREE_TYPE (primop));
8407 if (bits < TYPE_PRECISION (result_type)
8408 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8409 {
8410 mask = (~(HOST_WIDE_INT) 0) << bits;
8411 if ((mask & constant) != mask)
8412 warning (0, "comparison of promoted ~unsigned with constant");
8413 }
8414 }
8415 else if (unsignedp0 && unsignedp1
8416 && (TYPE_PRECISION (TREE_TYPE (primop0))
8417 < TYPE_PRECISION (result_type))
8418 && (TYPE_PRECISION (TREE_TYPE (primop1))
8419 < TYPE_PRECISION (result_type)))
8420 warning (0, "comparison of promoted ~unsigned with unsigned");
8421 }
8422 }
8423 }
8424 }
8425
8426 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8427 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8428 Then the expression will be built.
8429 It will be given type FINAL_TYPE if that is nonzero;
8430 otherwise, it will be given type RESULT_TYPE. */
8431
8432 if (!result_type)
8433 {
8434 binary_op_error (code, TREE_TYPE (op0), TREE_TYPE (op1));
8435 return error_mark_node;
8436 }
8437
8438 if (!converted)
8439 {
8440 if (TREE_TYPE (op0) != result_type)
8441 op0 = convert_and_check (result_type, op0);
8442 if (TREE_TYPE (op1) != result_type)
8443 op1 = convert_and_check (result_type, op1);
8444
8445 /* This can happen if one operand has a vector type, and the other
8446 has a different type. */
8447 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8448 return error_mark_node;
8449 }
8450
8451 if (build_type == NULL_TREE)
8452 build_type = result_type;
8453
8454 {
8455 /* Treat expressions in initializers specially as they can't trap. */
8456 tree result = require_constant_value ? fold_build2_initializer (resultcode,
8457 build_type,
8458 op0, op1)
8459 : fold_build2 (resultcode, build_type,
8460 op0, op1);
8461
8462 if (final_type != 0)
8463 result = convert (final_type, result);
8464 return result;
8465 }
8466}
8467
8468
8469/* Convert EXPR to be a truth-value, validating its type for this
8470 purpose. */
8471
8472tree
8473c_objc_common_truthvalue_conversion (tree expr)
8474{
8475 switch (TREE_CODE (TREE_TYPE (expr)))
8476 {
8477 case ARRAY_TYPE:
8478 error ("used array that cannot be converted to pointer where scalar is required");
8479 return error_mark_node;
8480
8481 case RECORD_TYPE:
8482 error ("used struct type value where scalar is required");
8483 return error_mark_node;
8484
8485 case UNION_TYPE:
8486 error ("used union type value where scalar is required");
8487 return error_mark_node;
8488
8489 case FUNCTION_TYPE:
8490 gcc_unreachable ();
8491
8492 default:
8493 break;
8494 }
8495
8496 /* ??? Should we also give an error for void and vectors rather than
8497 leaving those to give errors later? */
8498 return c_common_truthvalue_conversion (expr);
8499}
8500
8501
8502/* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
8503 required. */
8504
8505tree
8506c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED,
8507 bool *ti ATTRIBUTE_UNUSED, bool *se)
8508{
8509 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR)
8510 {
8511 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr);
8512 /* Executing a compound literal inside a function reinitializes
8513 it. */
8514 if (!TREE_STATIC (decl))
8515 *se = true;
8516 return decl;
8517 }
8518 else
8519 return expr;
8520}
8521
8522/* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
8523
8524tree
8525c_begin_omp_parallel (void)
8526{
8527 tree block;
8528
8529 keep_next_level ();
8530 block = c_begin_compound_stmt (true);
8531
8532 return block;
8533}
8534
8535tree
8536c_finish_omp_parallel (tree clauses, tree block)
8537{
8538 tree stmt;
8539
8540 block = c_end_compound_stmt (block, true);
8541
8542 stmt = make_node (OMP_PARALLEL);
8543 TREE_TYPE (stmt) = void_type_node;
8544 OMP_PARALLEL_CLAUSES (stmt) = clauses;
8545 OMP_PARALLEL_BODY (stmt) = block;
8546
8547 return add_stmt (stmt);
8548}
8549
8550/* For all elements of CLAUSES, validate them vs OpenMP constraints.
8551 Remove any elements from the list that are invalid. */
8552
8553tree
8554c_finish_omp_clauses (tree clauses)
8555{
8556 bitmap_head generic_head, firstprivate_head, lastprivate_head;
8557 tree c, t, *pc = &clauses;
8558 const char *name;
8559
8560 bitmap_obstack_initialize (NULL);
8561 bitmap_initialize (&generic_head, &bitmap_default_obstack);
8562 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack);
8563 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack);
8564
8565 for (pc = &clauses, c = clauses; c ; c = *pc)
8566 {
8567 bool remove = false;
8568 bool need_complete = false;
8569 bool need_implicitly_determined = false;
8570
8571 switch (OMP_CLAUSE_CODE (c))
8572 {
8573 case OMP_CLAUSE_SHARED:
8574 name = "shared";
8575 need_implicitly_determined = true;
8576 goto check_dup_generic;
8577
8578 case OMP_CLAUSE_PRIVATE:
8579 name = "private";
8580 need_complete = true;
8581 need_implicitly_determined = true;
8582 goto check_dup_generic;
8583
8584 case OMP_CLAUSE_REDUCTION:
8585 name = "reduction";
8586 need_implicitly_determined = true;
8587 t = OMP_CLAUSE_DECL (c);
8588 if (AGGREGATE_TYPE_P (TREE_TYPE (t))
8589 || POINTER_TYPE_P (TREE_TYPE (t)))
8590 {
8591 error ("%qE has invalid type for %<reduction%>", t);
8592 remove = true;
8593 }
8594 else if (FLOAT_TYPE_P (TREE_TYPE (t)))
8595 {
8596 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c);
8597 const char *r_name = NULL;
8598
8599 switch (r_code)
8600 {
8601 case PLUS_EXPR:
8602 case MULT_EXPR:
8603 case MINUS_EXPR:
8604 break;
8605 case BIT_AND_EXPR:
8606 r_name = "&";
8607 break;
8608 case BIT_XOR_EXPR:
8609 r_name = "^";
8610 break;
8611 case BIT_IOR_EXPR:
8612 r_name = "|";
8613 break;
8614 case TRUTH_ANDIF_EXPR:
8615 r_name = "&&";
8616 break;
8617 case TRUTH_ORIF_EXPR:
8618 r_name = "||";
8619 break;
8620 default:
8621 gcc_unreachable ();
8622 }
8623 if (r_name)
8624 {
8625 error ("%qE has invalid type for %<reduction(%s)%>",
8626 t, r_name);
8627 remove = true;
8628 }
8629 }
8630 goto check_dup_generic;
8631
8632 case OMP_CLAUSE_COPYPRIVATE:
8633 name = "copyprivate";
8634 goto check_dup_generic;
8635
8636 case OMP_CLAUSE_COPYIN:
8637 name = "copyin";
8638 t = OMP_CLAUSE_DECL (c);
8639 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t))
8640 {
8641 error ("%qE must be %<threadprivate%> for %<copyin%>", t);
8642 remove = true;
8643 }
8644 goto check_dup_generic;
8645
8646 check_dup_generic:
8647 t = OMP_CLAUSE_DECL (c);
8648 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8649 {
8650 error ("%qE is not a variable in clause %qs", t, name);
8651 remove = true;
8652 }
8653 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8654 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))
8655 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8656 {
8657 error ("%qE appears more than once in data clauses", t);
8658 remove = true;
8659 }
8660 else
8661 bitmap_set_bit (&generic_head, DECL_UID (t));
8662 break;
8663
8664 case OMP_CLAUSE_FIRSTPRIVATE:
8665 name = "firstprivate";
8666 t = OMP_CLAUSE_DECL (c);
8667 need_complete = true;
8668 need_implicitly_determined = true;
8669 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8670 {
8671 error ("%qE is not a variable in clause %<firstprivate%>", t);
8672 remove = true;
8673 }
8674 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8675 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
8676 {
8677 error ("%qE appears more than once in data clauses", t);
8678 remove = true;
8679 }
8680 else
8681 bitmap_set_bit (&firstprivate_head, DECL_UID (t));
8682 break;
8683
8684 case OMP_CLAUSE_LASTPRIVATE:
8685 name = "lastprivate";
8686 t = OMP_CLAUSE_DECL (c);
8687 need_complete = true;
8688 need_implicitly_determined = true;
8689 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8690 {
8691 error ("%qE is not a variable in clause %<lastprivate%>", t);
8692 remove = true;
8693 }
8694 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8695 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8696 {
8697 error ("%qE appears more than once in data clauses", t);
8698 remove = true;
8699 }
8700 else
8701 bitmap_set_bit (&lastprivate_head, DECL_UID (t));
8702 break;
8703
8704 case OMP_CLAUSE_IF:
8705 case OMP_CLAUSE_NUM_THREADS:
8706 case OMP_CLAUSE_SCHEDULE:
8707 case OMP_CLAUSE_NOWAIT:
8708 case OMP_CLAUSE_ORDERED:
8709 case OMP_CLAUSE_DEFAULT:
8710 pc = &OMP_CLAUSE_CHAIN (c);
8711 continue;
8712
8713 default:
8714 gcc_unreachable ();
8715 }
8716
8717 if (!remove)
8718 {
8719 t = OMP_CLAUSE_DECL (c);
8720
8721 if (need_complete)
8722 {
8723 t = require_complete_type (t);
8724 if (t == error_mark_node)
8725 remove = true;
8726 }
8727
8728 if (need_implicitly_determined)
8729 {
8730 const char *share_name = NULL;
8731
8732 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t))
8733 share_name = "threadprivate";
8734 else switch (c_omp_predetermined_sharing (t))
8735 {
8736 case OMP_CLAUSE_DEFAULT_UNSPECIFIED:
8737 break;
8738 case OMP_CLAUSE_DEFAULT_SHARED:
8739 share_name = "shared";
8740 break;
8741 case OMP_CLAUSE_DEFAULT_PRIVATE:
8742 share_name = "private";
8743 break;
8744 default:
8745 gcc_unreachable ();
8746 }
8747 if (share_name)
8748 {
8749 error ("%qE is predetermined %qs for %qs",
8750 t, share_name, name);
8751 remove = true;
8752 }
8753 }
8754 }
8755
8756 if (remove)
8757 *pc = OMP_CLAUSE_CHAIN (c);
8758 else
8759 pc = &OMP_CLAUSE_CHAIN (c);
8760 }
8761
8762 bitmap_obstack_release (NULL);
8763 return clauses;
8764}
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