1/* Subroutines shared by all languages that are variants of C.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 2, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING. If not, write to the Free
19Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
2002110-1301, USA. */
21
22#include "config.h"
23#include "system.h"
24#include "coretypes.h"
25#include "tm.h"
26#include "intl.h"
27#include "tree.h"
28#include "flags.h"
29#include "output.h"
30#include "c-pragma.h"
31#include "rtl.h"
32#include "ggc.h"
33#include "varray.h"
34#include "expr.h"
35#include "c-common.h"
36#include "diagnostic.h"
37#include "tm_p.h"
38#include "obstack.h"
39#include "cpplib.h"
40#include "target.h"
41#include "langhooks.h"
42#include "tree-inline.h"
43#include "c-tree.h"
44#include "toplev.h"
45#include "tree-iterator.h"
46#include "hashtab.h"
47#include "tree-mudflap.h"
48#include "opts.h"
49#include "real.h"
50#include "cgraph.h"
51
52cpp_reader *parse_in; /* Declared in c-pragma.h. */
53
54/* We let tm.h override the types used here, to handle trivial differences
55 such as the choice of unsigned int or long unsigned int for size_t.
56 When machines start needing nontrivial differences in the size type,
57 it would be best to do something here to figure out automatically
58 from other information what type to use. */
59
60#ifndef SIZE_TYPE
61#define SIZE_TYPE "long unsigned int"
62#endif
63
64#ifndef PID_TYPE
65#define PID_TYPE "int"
66#endif
67
68#ifndef WCHAR_TYPE
69#define WCHAR_TYPE "int"
70#endif
71
72/* WCHAR_TYPE gets overridden by -fshort-wchar. */
73#define MODIFIED_WCHAR_TYPE \
74 (flag_short_wchar ? "short unsigned int" : WCHAR_TYPE)
75
76#ifndef PTRDIFF_TYPE
77#define PTRDIFF_TYPE "long int"
78#endif
79
80#ifndef WINT_TYPE
81#define WINT_TYPE "unsigned int"
82#endif
83
84#ifndef INTMAX_TYPE
85#define INTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
86 ? "int" \
87 : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
88 ? "long int" \
89 : "long long int"))
90#endif
91
92#ifndef UINTMAX_TYPE
93#define UINTMAX_TYPE ((INT_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
94 ? "unsigned int" \
95 : ((LONG_TYPE_SIZE == LONG_LONG_TYPE_SIZE) \
96 ? "long unsigned int" \
97 : "long long unsigned int"))
98#endif
99
100/* The following symbols are subsumed in the c_global_trees array, and
101 listed here individually for documentation purposes.
102
103 INTEGER_TYPE and REAL_TYPE nodes for the standard data types.
104
105 tree short_integer_type_node;
106 tree long_integer_type_node;
107 tree long_long_integer_type_node;
108
109 tree short_unsigned_type_node;
110 tree long_unsigned_type_node;
111 tree long_long_unsigned_type_node;
112
113 tree truthvalue_type_node;
114 tree truthvalue_false_node;
115 tree truthvalue_true_node;
116
117 tree ptrdiff_type_node;
118
119 tree unsigned_char_type_node;
120 tree signed_char_type_node;
121 tree wchar_type_node;
122 tree signed_wchar_type_node;
123 tree unsigned_wchar_type_node;
124
125 tree float_type_node;
126 tree double_type_node;
127 tree long_double_type_node;
128
129 tree complex_integer_type_node;
130 tree complex_float_type_node;
131 tree complex_double_type_node;
132 tree complex_long_double_type_node;
133
134 tree dfloat32_type_node;
135 tree dfloat64_type_node;
136 tree_dfloat128_type_node;
137
138 tree intQI_type_node;
139 tree intHI_type_node;
140 tree intSI_type_node;
141 tree intDI_type_node;
142 tree intTI_type_node;
143
144 tree unsigned_intQI_type_node;
145 tree unsigned_intHI_type_node;
146 tree unsigned_intSI_type_node;
147 tree unsigned_intDI_type_node;
148 tree unsigned_intTI_type_node;
149
150 tree widest_integer_literal_type_node;
151 tree widest_unsigned_literal_type_node;
152
153 Nodes for types `void *' and `const void *'.
154
155 tree ptr_type_node, const_ptr_type_node;
156
157 Nodes for types `char *' and `const char *'.
158
159 tree string_type_node, const_string_type_node;
160
161 Type `char[SOMENUMBER]'.
162 Used when an array of char is needed and the size is irrelevant.
163
164 tree char_array_type_node;
165
166 Type `int[SOMENUMBER]' or something like it.
167 Used when an array of int needed and the size is irrelevant.
168
169 tree int_array_type_node;
170
171 Type `wchar_t[SOMENUMBER]' or something like it.
172 Used when a wide string literal is created.
173
174 tree wchar_array_type_node;
175
176 Type `int ()' -- used for implicit declaration of functions.
177
178 tree default_function_type;
179
180 A VOID_TYPE node, packaged in a TREE_LIST.
181
182 tree void_list_node;
183
184 The lazily created VAR_DECLs for __FUNCTION__, __PRETTY_FUNCTION__,
185 and __func__. (C doesn't generate __FUNCTION__ and__PRETTY_FUNCTION__
186 VAR_DECLS, but C++ does.)
187
188 tree function_name_decl_node;
189 tree pretty_function_name_decl_node;
190 tree c99_function_name_decl_node;
191
192 Stack of nested function name VAR_DECLs.
193
194 tree saved_function_name_decls;
195
196*/
197
198tree c_global_trees[CTI_MAX];
199
200/* Switches common to the C front ends. */
201
202/* Nonzero if prepreprocessing only. */
203
204int flag_preprocess_only;
205
206/* Nonzero means don't output line number information. */
207
208char flag_no_line_commands;
209
210/* Nonzero causes -E output not to be done, but directives such as
211 #define that have side effects are still obeyed. */
212
213char flag_no_output;
214
215/* Nonzero means dump macros in some fashion. */
216
217char flag_dump_macros;
218
219/* Nonzero means pass #include lines through to the output. */
220
221char flag_dump_includes;
222
223/* Nonzero means process PCH files while preprocessing. */
224
225bool flag_pch_preprocess;
226
227/* The file name to which we should write a precompiled header, or
228 NULL if no header will be written in this compile. */
229
230const char *pch_file;
231
232/* Nonzero if an ISO standard was selected. It rejects macros in the
233 user's namespace. */
234int flag_iso;
235
236/* Nonzero if -undef was given. It suppresses target built-in macros
237 and assertions. */
238int flag_undef;
239
240/* Nonzero means don't recognize the non-ANSI builtin functions. */
241
242int flag_no_builtin;
243
244/* Nonzero means don't recognize the non-ANSI builtin functions.
245 -ansi sets this. */
246
247int flag_no_nonansi_builtin;
248
249/* Nonzero means give `double' the same size as `float'. */
250
251int flag_short_double;
252
253/* Nonzero means give `wchar_t' the same size as `short'. */
254
255int flag_short_wchar;
256
257/* Nonzero means allow implicit conversions between vectors with
258 differing numbers of subparts and/or differing element types. */
259int flag_lax_vector_conversions;
260
261/* Nonzero means allow Microsoft extensions without warnings or errors. */
262int flag_ms_extensions;
263
264/* Nonzero means don't recognize the keyword `asm'. */
265
266int flag_no_asm;
267
268/* Nonzero means to treat bitfields as signed unless they say `unsigned'. */
269
270int flag_signed_bitfields = 1;
271
272/* Warn about #pragma directives that are not recognized. */
273
274int warn_unknown_pragmas; /* Tri state variable. */
275
276/* Warn about format/argument anomalies in calls to formatted I/O functions
277 (*printf, *scanf, strftime, strfmon, etc.). */
278
279int warn_format;
280
281/* Warn about using __null (as NULL in C++) as sentinel. For code compiled
282 with GCC this doesn't matter as __null is guaranteed to have the right
283 size. */
284
285int warn_strict_null_sentinel;
286
287/* Zero means that faster, ...NonNil variants of objc_msgSend...
288 calls will be used in ObjC; passing nil receivers to such calls
289 will most likely result in crashes. */
290int flag_nil_receivers = 1;
291
292/* Nonzero means that code generation will be altered to support
293 "zero-link" execution. This currently affects ObjC only, but may
294 affect other languages in the future. */
295int flag_zero_link = 0;
296
297/* Nonzero means emit an '__OBJC, __image_info' for the current translation
298 unit. It will inform the ObjC runtime that class definition(s) herein
299 contained are to replace one(s) previously loaded. */
300int flag_replace_objc_classes = 0;
301
302/* C/ObjC language option variables. */
303
304
305/* Nonzero means allow type mismatches in conditional expressions;
306 just make their values `void'. */
307
308int flag_cond_mismatch;
309
310/* Nonzero means enable C89 Amendment 1 features. */
311
312int flag_isoc94;
313
314/* Nonzero means use the ISO C99 dialect of C. */
315
316int flag_isoc99;
317
318/* Nonzero means that we have builtin functions, and main is an int. */
319
320int flag_hosted = 1;
321
322/* Warn if main is suspicious. */
323
324int warn_main;
325
326
327/* ObjC language option variables. */
328
329
330/* Open and close the file for outputting class declarations, if
331 requested (ObjC). */
332
333int flag_gen_declaration;
334
335/* Tells the compiler that this is a special run. Do not perform any
336 compiling, instead we are to test some platform dependent features
337 and output a C header file with appropriate definitions. */
338
339int print_struct_values;
340
341/* Tells the compiler what is the constant string class for Objc. */
342
343const char *constant_string_class_name;
344
345
346/* C++ language option variables. */
347
348
349/* Nonzero means don't recognize any extension keywords. */
350
351int flag_no_gnu_keywords;
352
353/* Nonzero means do emit exported implementations of functions even if
354 they can be inlined. */
355
356int flag_implement_inlines = 1;
357
358/* Nonzero means that implicit instantiations will be emitted if needed. */
359
360int flag_implicit_templates = 1;
361
362/* Nonzero means that implicit instantiations of inline templates will be
363 emitted if needed, even if instantiations of non-inline templates
364 aren't. */
365
366int flag_implicit_inline_templates = 1;
367
368/* Nonzero means generate separate instantiation control files and
369 juggle them at link time. */
370
371int flag_use_repository;
372
373/* Nonzero if we want to issue diagnostics that the standard says are not
374 required. */
375
376int flag_optional_diags = 1;
377
378/* Nonzero means we should attempt to elide constructors when possible. */
379
380int flag_elide_constructors = 1;
381
382/* Nonzero means that member functions defined in class scope are
383 inline by default. */
384
385int flag_default_inline = 1;
386
387/* Controls whether compiler generates 'type descriptor' that give
388 run-time type information. */
389
390int flag_rtti = 1;
391
392/* Nonzero if we want to conserve space in the .o files. We do this
393 by putting uninitialized data and runtime initialized data into
394 .common instead of .data at the expense of not flagging multiple
395 definitions. */
396
397int flag_conserve_space;
398
399/* Nonzero if we want to obey access control semantics. */
400
401int flag_access_control = 1;
402
403/* Nonzero if we want to check the return value of new and avoid calling
404 constructors if it is a null pointer. */
405
406int flag_check_new;
407
408/* Nonzero if we want the new ISO rules for pushing a new scope for `for'
409 initialization variables.
410 0: Old rules, set by -fno-for-scope.
411 2: New ISO rules, set by -ffor-scope.
412 1: Try to implement new ISO rules, but with backup compatibility
413 (and warnings). This is the default, for now. */
414
415int flag_new_for_scope = 1;
416
417/* Nonzero if we want to emit defined symbols with common-like linkage as
418 weak symbols where possible, in order to conform to C++ semantics.
419 Otherwise, emit them as local symbols. */
420
421int flag_weak = 1;
422
423/* 0 means we want the preprocessor to not emit line directives for
424 the current working directory. 1 means we want it to do it. -1
425 means we should decide depending on whether debugging information
426 is being emitted or not. */
427
428int flag_working_directory = -1;
429
430/* Nonzero to use __cxa_atexit, rather than atexit, to register
431 destructors for local statics and global objects. '2' means it has been
432 set nonzero as a default, not by a command-line flag. */
433
434int flag_use_cxa_atexit = DEFAULT_USE_CXA_ATEXIT;
435
436/* Nonzero to use __cxa_get_exception_ptr in C++ exception-handling
437 code. '2' means it has not been set explicitly on the command line. */
438
439int flag_use_cxa_get_exception_ptr = 2;
440
441/* Nonzero means make the default pedwarns warnings instead of errors.
442 The value of this flag is ignored if -pedantic is specified. */
443
444int flag_permissive;
445
446/* Nonzero means to implement standard semantics for exception
447 specifications, calling unexpected if an exception is thrown that
448 doesn't match the specification. Zero means to treat them as
449 assertions and optimize accordingly, but not check them. */
450
451int flag_enforce_eh_specs = 1;
452
453/* Nonzero means to generate thread-safe code for initializing local
454 statics. */
455
456int flag_threadsafe_statics = 1;
457
458/* Nonzero means warn about implicit declarations. */
459
460int warn_implicit = 1;
461
462/* Maximum template instantiation depth. This limit is rather
463 arbitrary, but it exists to limit the time it takes to notice
464 infinite template instantiations. */
465
466int max_tinst_depth = 500;
467
468
469
470/* The elements of `ridpointers' are identifier nodes for the reserved
471 type names and storage classes. It is indexed by a RID_... value. */
472tree *ridpointers;
473
474tree (*make_fname_decl) (tree, int);
475
476/* Nonzero means the expression being parsed will never be evaluated.
477 This is a count, since unevaluated expressions can nest. */
478int skip_evaluation;
479
480/* Information about how a function name is generated. */
481struct fname_var_t
482{
483 tree *const decl; /* pointer to the VAR_DECL. */
484 const unsigned rid; /* RID number for the identifier. */
485 const int pretty; /* How pretty is it? */
486};
487
488/* The three ways of getting then name of the current function. */
489
490const struct fname_var_t fname_vars[] =
491{
492 /* C99 compliant __func__, must be first. */
493 {&c99_function_name_decl_node, RID_C99_FUNCTION_NAME, 0},
494 /* GCC __FUNCTION__ compliant. */
495 {&function_name_decl_node, RID_FUNCTION_NAME, 0},
496 /* GCC __PRETTY_FUNCTION__ compliant. */
497 {&pretty_function_name_decl_node, RID_PRETTY_FUNCTION_NAME, 1},
498 {NULL, 0, 0},
499};
500
501static int constant_fits_type_p (tree, tree);
502static tree check_case_value (tree);
503static bool check_case_bounds (tree, tree, tree *, tree *);
504
505static tree handle_packed_attribute (tree *, tree, tree, int, bool *);
506static tree handle_nocommon_attribute (tree *, tree, tree, int, bool *);
507static tree handle_common_attribute (tree *, tree, tree, int, bool *);
508static tree handle_noreturn_attribute (tree *, tree, tree, int, bool *);
509static tree handle_noinline_attribute (tree *, tree, tree, int, bool *);
510static tree handle_always_inline_attribute (tree *, tree, tree, int,
511 bool *);
512static tree handle_gnu_inline_attribute (tree *, tree, tree, int,
513 bool *);
514static tree handle_flatten_attribute (tree *, tree, tree, int, bool *);
515static tree handle_used_attribute (tree *, tree, tree, int, bool *);
516static tree handle_unused_attribute (tree *, tree, tree, int, bool *);
517static tree handle_externally_visible_attribute (tree *, tree, tree, int,
518 bool *);
519static tree handle_const_attribute (tree *, tree, tree, int, bool *);
520static tree handle_transparent_union_attribute (tree *, tree, tree,
521 int, bool *);
522static tree handle_constructor_attribute (tree *, tree, tree, int, bool *);
523static tree handle_destructor_attribute (tree *, tree, tree, int, bool *);
524static tree handle_mode_attribute (tree *, tree, tree, int, bool *);
525static tree handle_section_attribute (tree *, tree, tree, int, bool *);
526static tree handle_aligned_attribute (tree *, tree, tree, int, bool *);
527static tree handle_weak_attribute (tree *, tree, tree, int, bool *) ;
528static tree handle_alias_attribute (tree *, tree, tree, int, bool *);
529static tree handle_weakref_attribute (tree *, tree, tree, int, bool *) ;
530static tree handle_visibility_attribute (tree *, tree, tree, int,
531 bool *);
532static tree handle_tls_model_attribute (tree *, tree, tree, int,
533 bool *);
534static tree handle_no_instrument_function_attribute (tree *, tree,
535 tree, int, bool *);
536static tree handle_malloc_attribute (tree *, tree, tree, int, bool *);
537static tree handle_returns_twice_attribute (tree *, tree, tree, int, bool *);
538static tree handle_no_limit_stack_attribute (tree *, tree, tree, int,
539 bool *);
540static tree handle_pure_attribute (tree *, tree, tree, int, bool *);
541static tree handle_novops_attribute (tree *, tree, tree, int, bool *);
542static tree handle_deprecated_attribute (tree *, tree, tree, int,
543 bool *);
544static tree handle_vector_size_attribute (tree *, tree, tree, int,
545 bool *);
546static tree handle_nonnull_attribute (tree *, tree, tree, int, bool *);
547static tree handle_nothrow_attribute (tree *, tree, tree, int, bool *);
548static tree handle_cleanup_attribute (tree *, tree, tree, int, bool *);
549static tree handle_warn_unused_result_attribute (tree *, tree, tree, int,
550 bool *);
551static tree handle_sentinel_attribute (tree *, tree, tree, int, bool *);
552
553static void check_function_nonnull (tree, tree);
554static void check_nonnull_arg (void *, tree, unsigned HOST_WIDE_INT);
555static bool nonnull_check_p (tree, unsigned HOST_WIDE_INT);
556static bool get_nonnull_operand (tree, unsigned HOST_WIDE_INT *);
557static int resort_field_decl_cmp (const void *, const void *);
558
559/* Table of machine-independent attributes common to all C-like languages. */
560const struct attribute_spec c_common_attribute_table[] =
561{
562 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
563 { "packed", 0, 0, false, false, false,
564 handle_packed_attribute },
565 { "nocommon", 0, 0, true, false, false,
566 handle_nocommon_attribute },
567 { "common", 0, 0, true, false, false,
568 handle_common_attribute },
569 /* FIXME: logically, noreturn attributes should be listed as
570 "false, true, true" and apply to function types. But implementing this
571 would require all the places in the compiler that use TREE_THIS_VOLATILE
572 on a decl to identify non-returning functions to be located and fixed
573 to check the function type instead. */
574 { "noreturn", 0, 0, true, false, false,
575 handle_noreturn_attribute },
576 { "volatile", 0, 0, true, false, false,
577 handle_noreturn_attribute },
578 { "noinline", 0, 0, true, false, false,
579 handle_noinline_attribute },
580 { "always_inline", 0, 0, true, false, false,
581 handle_always_inline_attribute },
582 { "gnu_inline", 0, 0, true, false, false,
583 handle_gnu_inline_attribute },
584 { "flatten", 0, 0, true, false, false,
585 handle_flatten_attribute },
586 { "used", 0, 0, true, false, false,
587 handle_used_attribute },
588 { "unused", 0, 0, false, false, false,
589 handle_unused_attribute },
590 { "externally_visible", 0, 0, true, false, false,
591 handle_externally_visible_attribute },
592 /* The same comments as for noreturn attributes apply to const ones. */
593 { "const", 0, 0, true, false, false,
594 handle_const_attribute },
595 { "transparent_union", 0, 0, false, false, false,
596 handle_transparent_union_attribute },
597 { "constructor", 0, 0, true, false, false,
598 handle_constructor_attribute },
599 { "destructor", 0, 0, true, false, false,
600 handle_destructor_attribute },
601 { "mode", 1, 1, false, true, false,
602 handle_mode_attribute },
603 { "section", 1, 1, true, false, false,
604 handle_section_attribute },
605 { "aligned", 0, 1, false, false, false,
606 handle_aligned_attribute },
607 { "weak", 0, 0, true, false, false,
608 handle_weak_attribute },
609 { "alias", 1, 1, true, false, false,
610 handle_alias_attribute },
611 { "weakref", 0, 1, true, false, false,
612 handle_weakref_attribute },
613 { "no_instrument_function", 0, 0, true, false, false,
614 handle_no_instrument_function_attribute },
615 { "malloc", 0, 0, true, false, false,
616 handle_malloc_attribute },
617 { "returns_twice", 0, 0, true, false, false,
618 handle_returns_twice_attribute },
619 { "no_stack_limit", 0, 0, true, false, false,
620 handle_no_limit_stack_attribute },
621 { "pure", 0, 0, true, false, false,
622 handle_pure_attribute },
623 /* For internal use (marking of builtins) only. The name contains space
624 to prevent its usage in source code. */
625 { "no vops", 0, 0, true, false, false,
626 handle_novops_attribute },
627 { "deprecated", 0, 0, false, false, false,
628 handle_deprecated_attribute },
629 { "vector_size", 1, 1, false, true, false,
630 handle_vector_size_attribute },
631 { "visibility", 1, 1, false, false, false,
632 handle_visibility_attribute },
633 { "tls_model", 1, 1, true, false, false,
634 handle_tls_model_attribute },
635 { "nonnull", 0, -1, false, true, true,
636 handle_nonnull_attribute },
637 { "nothrow", 0, 0, true, false, false,
638 handle_nothrow_attribute },
639 { "may_alias", 0, 0, false, true, false, NULL },
640 { "cleanup", 1, 1, true, false, false,
641 handle_cleanup_attribute },
642 { "warn_unused_result", 0, 0, false, true, true,
643 handle_warn_unused_result_attribute },
644 { "sentinel", 0, 1, false, true, true,
645 handle_sentinel_attribute },
646 { NULL, 0, 0, false, false, false, NULL }
647};
648
649/* Give the specifications for the format attributes, used by C and all
650 descendants. */
651
652const struct attribute_spec c_common_format_attribute_table[] =
653{
654 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler } */
655 { "format", 3, 3, false, true, true,
656 handle_format_attribute },
657 { "format_arg", 1, 1, false, true, true,
658 handle_format_arg_attribute },
659 { NULL, 0, 0, false, false, false, NULL }
660};
661
662/* Push current bindings for the function name VAR_DECLS. */
663
664void
665start_fname_decls (void)
666{
667 unsigned ix;
668 tree saved = NULL_TREE;
669
670 for (ix = 0; fname_vars[ix].decl; ix++)
671 {
672 tree decl = *fname_vars[ix].decl;
673
674 if (decl)
675 {
676 saved = tree_cons (decl, build_int_cst (NULL_TREE, ix), saved);
677 *fname_vars[ix].decl = NULL_TREE;
678 }
679 }
680 if (saved || saved_function_name_decls)
681 /* Normally they'll have been NULL, so only push if we've got a
682 stack, or they are non-NULL. */
683 saved_function_name_decls = tree_cons (saved, NULL_TREE,
684 saved_function_name_decls);
685}
686
687/* Finish up the current bindings, adding them into the current function's
688 statement tree. This must be done _before_ finish_stmt_tree is called.
689 If there is no current function, we must be at file scope and no statements
690 are involved. Pop the previous bindings. */
691
692void
693finish_fname_decls (void)
694{
695 unsigned ix;
696 tree stmts = NULL_TREE;
697 tree stack = saved_function_name_decls;
698
699 for (; stack && TREE_VALUE (stack); stack = TREE_CHAIN (stack))
700 append_to_statement_list (TREE_VALUE (stack), &stmts);
701
702 if (stmts)
703 {
704 tree *bodyp = &DECL_SAVED_TREE (current_function_decl);
705
706 if (TREE_CODE (*bodyp) == BIND_EXPR)
707 bodyp = &BIND_EXPR_BODY (*bodyp);
708
709 append_to_statement_list_force (*bodyp, &stmts);
710 *bodyp = stmts;
711 }
712
713 for (ix = 0; fname_vars[ix].decl; ix++)
714 *fname_vars[ix].decl = NULL_TREE;
715
716 if (stack)
717 {
718 /* We had saved values, restore them. */
719 tree saved;
720
721 for (saved = TREE_PURPOSE (stack); saved; saved = TREE_CHAIN (saved))
722 {
723 tree decl = TREE_PURPOSE (saved);
724 unsigned ix = TREE_INT_CST_LOW (TREE_VALUE (saved));
725
726 *fname_vars[ix].decl = decl;
727 }
728 stack = TREE_CHAIN (stack);
729 }
730 saved_function_name_decls = stack;
731}
732
733/* Return the text name of the current function, suitably prettified
734 by PRETTY_P. Return string must be freed by caller. */
735
736const char *
737fname_as_string (int pretty_p)
738{
739 const char *name = "top level";
740 char *namep;
741 int vrb = 2;
742
743 if (!pretty_p)
744 {
745 name = "";
746 vrb = 0;
747 }
748
749 if (current_function_decl)
750 name = lang_hooks.decl_printable_name (current_function_decl, vrb);
751
752 if (c_lex_string_translate)
753 {
754 int len = strlen (name) + 3; /* Two for '"'s. One for NULL. */
755 cpp_string cstr = { 0, 0 }, strname;
756
757 namep = XNEWVEC (char, len);
758 snprintf (namep, len, "\"%s\"", name);
759 strname.text = (unsigned char *) namep;
760 strname.len = len - 1;
761
762 if (cpp_interpret_string (parse_in, &strname, 1, &cstr, false))
763 {
764 XDELETEVEC (namep);
765 return (char *) cstr.text;
766 }
767 }
768 else
769 namep = xstrdup (name);
770
771 return namep;
772}
773
774/* Expand DECL if it declares an entity not handled by the
775 common code. */
776
777int
778c_expand_decl (tree decl)
779{
780 if (TREE_CODE (decl) == VAR_DECL && !TREE_STATIC (decl))
781 {
782 /* Let the back-end know about this variable. */
783 if (!anon_aggr_type_p (TREE_TYPE (decl)))
784 emit_local_var (decl);
785 else
786 expand_anon_union_decl (decl, NULL_TREE,
787 DECL_ANON_UNION_ELEMS (decl));
788 }
789 else
790 return 0;
791
792 return 1;
793}
794
795
796/* Return the VAR_DECL for a const char array naming the current
797 function. If the VAR_DECL has not yet been created, create it
798 now. RID indicates how it should be formatted and IDENTIFIER_NODE
799 ID is its name (unfortunately C and C++ hold the RID values of
800 keywords in different places, so we can't derive RID from ID in
801 this language independent code. */
802
803tree
804fname_decl (unsigned int rid, tree id)
805{
806 unsigned ix;
807 tree decl = NULL_TREE;
808
809 for (ix = 0; fname_vars[ix].decl; ix++)
810 if (fname_vars[ix].rid == rid)
811 break;
812
813 decl = *fname_vars[ix].decl;
814 if (!decl)
815 {
816 /* If a tree is built here, it would normally have the lineno of
817 the current statement. Later this tree will be moved to the
818 beginning of the function and this line number will be wrong.
819 To avoid this problem set the lineno to 0 here; that prevents
820 it from appearing in the RTL. */
821 tree stmts;
822 location_t saved_location = input_location;
823#ifdef USE_MAPPED_LOCATION
824 input_location = UNKNOWN_LOCATION;
825#else
826 input_line = 0;
827#endif
828
829 stmts = push_stmt_list ();
830 decl = (*make_fname_decl) (id, fname_vars[ix].pretty);
831 stmts = pop_stmt_list (stmts);
832 if (!IS_EMPTY_STMT (stmts))
833 saved_function_name_decls
834 = tree_cons (decl, stmts, saved_function_name_decls);
835 *fname_vars[ix].decl = decl;
836 input_location = saved_location;
837 }
838 if (!ix && !current_function_decl)
839 pedwarn ("%qD is not defined outside of function scope", decl);
840
841 return decl;
842}
843
844/* Given a STRING_CST, give it a suitable array-of-chars data type. */
845
846tree
847fix_string_type (tree value)
848{
849 const int wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
850 const int wide_flag = TREE_TYPE (value) == wchar_array_type_node;
851 int length = TREE_STRING_LENGTH (value);
852 int nchars;
853 tree e_type, i_type, a_type;
854
855 /* Compute the number of elements, for the array type. */
856 nchars = wide_flag ? length / wchar_bytes : length;
857
858 /* C89 2.2.4.1, C99 5.2.4.1 (Translation limits). The analogous
859 limit in C++98 Annex B is very large (65536) and is not normative,
860 so we do not diagnose it (warn_overlength_strings is forced off
861 in c_common_post_options). */
862 if (warn_overlength_strings)
863 {
864 const int nchars_max = flag_isoc99 ? 4095 : 509;
865 const int relevant_std = flag_isoc99 ? 99 : 90;
866 if (nchars - 1 > nchars_max)
867 /* Translators: The %d after 'ISO C' will be 90 or 99. Do not
868 separate the %d from the 'C'. 'ISO' should not be
869 translated, but it may be moved after 'C%d' in languages
870 where modifiers follow nouns. */
871 pedwarn ("string length %qd is greater than the length %qd "
872 "ISO C%d compilers are required to support",
873 nchars - 1, nchars_max, relevant_std);
874 }
875
876 /* Create the array type for the string constant. The ISO C++
877 standard says that a string literal has type `const char[N]' or
878 `const wchar_t[N]'. We use the same logic when invoked as a C
879 front-end with -Wwrite-strings.
880 ??? We should change the type of an expression depending on the
881 state of a warning flag. We should just be warning -- see how
882 this is handled in the C++ front-end for the deprecated implicit
883 conversion from string literals to `char*' or `wchar_t*'.
884
885 The C++ front end relies on TYPE_MAIN_VARIANT of a cv-qualified
886 array type being the unqualified version of that type.
887 Therefore, if we are constructing an array of const char, we must
888 construct the matching unqualified array type first. The C front
889 end does not require this, but it does no harm, so we do it
890 unconditionally. */
891 e_type = wide_flag ? wchar_type_node : char_type_node;
892 i_type = build_index_type (build_int_cst (NULL_TREE, nchars - 1));
893 a_type = build_array_type (e_type, i_type);
894 if (c_dialect_cxx() || warn_write_strings)
895 a_type = c_build_qualified_type (a_type, TYPE_QUAL_CONST);
896
897 TREE_TYPE (value) = a_type;
898 TREE_CONSTANT (value) = 1;
899 TREE_INVARIANT (value) = 1;
900 TREE_READONLY (value) = 1;
901 TREE_STATIC (value) = 1;
902 return value;
903}
904
905/* Print a warning if a constant expression had overflow in folding.
906 Invoke this function on every expression that the language
907 requires to be a constant expression.
908 Note the ANSI C standard says it is erroneous for a
909 constant expression to overflow. */
910
911void
912constant_expression_warning (tree value)
913{
914 if ((TREE_CODE (value) == INTEGER_CST || TREE_CODE (value) == REAL_CST
915 || TREE_CODE (value) == VECTOR_CST
916 || TREE_CODE (value) == COMPLEX_CST)
917 && TREE_CONSTANT_OVERFLOW (value)
918 && warn_overflow
919 && pedantic)
920 pedwarn ("overflow in constant expression");
921}
922
923/* Print a warning if an expression had overflow in folding and its
924 operands hadn't.
925
926 Invoke this function on every expression that
927 (1) appears in the source code, and
928 (2) is a constant expression that overflowed, and
929 (3) is not already checked by convert_and_check;
930 however, do not invoke this function on operands of explicit casts
931 or when the expression is the result of an operator and any operand
932 already overflowed. */
933
934void
935overflow_warning (tree value)
936{
937 if (skip_evaluation) return;
938
939 switch (TREE_CODE (value))
940 {
941 case INTEGER_CST:
942 warning (OPT_Woverflow, "integer overflow in expression");
943 break;
944
945 case REAL_CST:
946 warning (OPT_Woverflow, "floating point overflow in expression");
947 break;
948
949 case VECTOR_CST:
950 warning (OPT_Woverflow, "vector overflow in expression");
951 break;
952
953 case COMPLEX_CST:
954 if (TREE_CODE (TREE_REALPART (value)) == INTEGER_CST)
955 warning (OPT_Woverflow, "complex integer overflow in expression");
956 else if (TREE_CODE (TREE_REALPART (value)) == REAL_CST)
957 warning (OPT_Woverflow, "complex floating point overflow in expression");
958 break;
959
960 default:
961 break;
962 }
963}
964
965/* Print a warning if a large constant is truncated to unsigned,
966 or if -Wconversion is used and a constant < 0 is converted to unsigned.
967 Invoke this function on every expression that might be implicitly
968 converted to an unsigned type. */
969
970static void
971unsigned_conversion_warning (tree result, tree operand)
972{
973 tree type = TREE_TYPE (result);
974
975 if (TREE_CODE (operand) == INTEGER_CST
976 && TREE_CODE (type) == INTEGER_TYPE
977 && TYPE_UNSIGNED (type)
978 && skip_evaluation == 0
979 && !int_fits_type_p (operand, type))
980 {
981 if (!int_fits_type_p (operand, c_common_signed_type (type)))
982 /* This detects cases like converting -129 or 256 to unsigned char. */
983 warning (OPT_Woverflow,
984 "large integer implicitly truncated to unsigned type");
985 else
986 warning (OPT_Wconversion,
987 "negative integer implicitly converted to unsigned type");
988 }
989}
990
991/* Print a warning about casts that might indicate violation
992 of strict aliasing rules if -Wstrict-aliasing is used and
993 strict aliasing mode is in effect. OTYPE is the original
994 TREE_TYPE of EXPR, and TYPE the type we're casting to. */
995
996bool
997strict_aliasing_warning (tree otype, tree type, tree expr)
998{
999 if (!(flag_strict_aliasing && POINTER_TYPE_P (type)
1000 && POINTER_TYPE_P (otype) && !VOID_TYPE_P (TREE_TYPE (type))))
1001 return false;
1002
1003 if ((warn_strict_aliasing > 1) && TREE_CODE (expr) == ADDR_EXPR
1004 && (DECL_P (TREE_OPERAND (expr, 0))
1005 || handled_component_p (TREE_OPERAND (expr, 0))))
1006 {
1007 /* Casting the address of an object to non void pointer. Warn
1008 if the cast breaks type based aliasing. */
1009 if (!COMPLETE_TYPE_P (TREE_TYPE (type)) && warn_strict_aliasing == 2)
1010 {
1011 warning (OPT_Wstrict_aliasing, "type-punning to incomplete type "
1012 "might break strict-aliasing rules");
1013 return true;
1014 }
1015 else
1016 {
1017 /* warn_strict_aliasing >= 3. This includes the default (3).
1018 Only warn if the cast is dereferenced immediately. */
1019 HOST_WIDE_INT set1 =
1020 get_alias_set (TREE_TYPE (TREE_OPERAND (expr, 0)));
1021 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type));
1022
1023 if (!alias_sets_conflict_p (set1, set2))
1024 {
1025 warning (OPT_Wstrict_aliasing, "dereferencing type-punned "
1026 "pointer will break strict-aliasing rules");
1027 return true;
1028 }
1029 else if (warn_strict_aliasing == 2
1030 && !alias_sets_might_conflict_p (set1, set2))
1031 {
1032 warning (OPT_Wstrict_aliasing, "dereferencing type-punned "
1033 "pointer might break strict-aliasing rules");
1034 return true;
1035 }
1036 }
1037 }
1038 else
1039 if ((warn_strict_aliasing == 1) && !VOID_TYPE_P (TREE_TYPE (otype)))
1040 {
1041 /* At this level, warn for any conversions, even if an address is
1042 not taken in the same statement. This will likely produce many
1043 false positives, but could be useful to pinpoint problems that
1044 are not revealed at higher levels. */
1045 HOST_WIDE_INT set1 = get_alias_set (TREE_TYPE (otype));
1046 HOST_WIDE_INT set2 = get_alias_set (TREE_TYPE (type));
1047 if (!COMPLETE_TYPE_P(type)
1048 || !alias_sets_might_conflict_p (set1, set2))
1049 {
1050 warning (OPT_Wstrict_aliasing, "dereferencing type-punned "
1051 "pointer might break strict-aliasing rules");
1052 return true;
1053 }
1054 }
1055
1056 return false;
1057}
1058
1059
1060/* Print a warning about if (); or if () .. else; constructs
1061 via the special empty statement node that we create. INNER_THEN
1062 and INNER_ELSE are the statement lists of the if and the else
1063 block. */
1064
1065void
1066empty_body_warning (tree inner_then, tree inner_else)
1067{
1068 if (extra_warnings)
1069 {
1070 if (TREE_CODE (inner_then) == STATEMENT_LIST
1071 && STATEMENT_LIST_TAIL (inner_then))
1072 inner_then = STATEMENT_LIST_TAIL (inner_then)->stmt;
1073
1074 if (inner_else && TREE_CODE (inner_else) == STATEMENT_LIST
1075 && STATEMENT_LIST_TAIL (inner_else))
1076 inner_else = STATEMENT_LIST_TAIL (inner_else)->stmt;
1077
1078 if (IS_EMPTY_STMT (inner_then) && !inner_else)
1079 warning (OPT_Wextra, "%Hempty body in an if-statement",
1080 EXPR_LOCUS (inner_then));
1081
1082 if (inner_else && IS_EMPTY_STMT (inner_else))
1083 warning (OPT_Wextra, "%Hempty body in an else-statement",
1084 EXPR_LOCUS (inner_else));
1085 }
1086}
1087
1088
1089/* Nonzero if constant C has a value that is permissible
1090 for type TYPE (an INTEGER_TYPE). */
1091
1092static int
1093constant_fits_type_p (tree c, tree type)
1094{
1095 if (TREE_CODE (c) == INTEGER_CST)
1096 return int_fits_type_p (c, type);
1097
1098 c = convert (type, c);
1099 return !TREE_OVERFLOW (c);
1100}
1101
1102
1103/* True if vector types T1 and T2 can be converted to each other
1104 without an explicit cast. If EMIT_LAX_NOTE is true, and T1 and T2
1105 can only be converted with -flax-vector-conversions yet that is not
1106 in effect, emit a note telling the user about that option if such
1107 a note has not previously been emitted. */
1108bool
1109vector_types_convertible_p (tree t1, tree t2, bool emit_lax_note)
1110{
1111 static bool emitted_lax_note = false;
1112 bool convertible_lax;
1113
1114 if ((targetm.vector_opaque_p (t1) || targetm.vector_opaque_p (t2))
1115 && tree_int_cst_equal (TYPE_SIZE (t1), TYPE_SIZE (t2)))
1116 return true;
1117
1118 convertible_lax =
1119 (tree_int_cst_equal (TYPE_SIZE (t1), TYPE_SIZE (t2))
1120 && (TREE_CODE (TREE_TYPE (t1)) != REAL_TYPE ||
1121 TYPE_PRECISION (t1) == TYPE_PRECISION (t2))
1122 && (INTEGRAL_TYPE_P (TREE_TYPE (t1))
1123 == INTEGRAL_TYPE_P (TREE_TYPE (t2))));
1124
1125 if (!convertible_lax || flag_lax_vector_conversions)
1126 return convertible_lax;
1127
1128 if (TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
1129 && comptypes (TREE_TYPE (t1), TREE_TYPE (t2)))
1130 return true;
1131
1132 if (emit_lax_note && !emitted_lax_note)
1133 {
1134 emitted_lax_note = true;
1135 inform ("use -flax-vector-conversions to permit "
1136 "conversions between vectors with differing "
1137 "element types or numbers of subparts");
1138 }
1139
1140 return false;
1141}
1142
1143/* Convert EXPR to TYPE, warning about conversion problems with constants.
1144 Invoke this function on every expression that is converted implicitly,
1145 i.e. because of language rules and not because of an explicit cast. */
1146
1147tree
1148convert_and_check (tree type, tree expr)
1149{
1150 tree t = convert (type, expr);
1151 if (TREE_CODE (t) == INTEGER_CST)
1152 {
1153 if (TREE_OVERFLOW (t))
1154 {
1155 TREE_OVERFLOW (t) = 0;
1156
1157 /* Do not diagnose overflow in a constant expression merely
1158 because a conversion overflowed. */
1159 TREE_CONSTANT_OVERFLOW (t) = CONSTANT_CLASS_P (expr)
1160 && TREE_CONSTANT_OVERFLOW (expr);
1161
1162 /* No warning for converting 0x80000000 to int. */
1163 if (!(TYPE_UNSIGNED (type) < TYPE_UNSIGNED (TREE_TYPE (expr))
1164 && TREE_CODE (TREE_TYPE (expr)) == INTEGER_TYPE
1165 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (expr))))
1166 /* If EXPR fits in the unsigned version of TYPE,
1167 don't warn unless pedantic. */
1168 if ((pedantic
1169 || TYPE_UNSIGNED (type)
1170 || !constant_fits_type_p (expr,
1171 c_common_unsigned_type (type)))
1172 && skip_evaluation == 0)
1173 warning (OPT_Woverflow,
1174 "overflow in implicit constant conversion");
1175 }
1176 else
1177 unsigned_conversion_warning (t, expr);
1178 }
1179 return t;
1180}
1181
1182/* A node in a list that describes references to variables (EXPR), which are
1183 either read accesses if WRITER is zero, or write accesses, in which case
1184 WRITER is the parent of EXPR. */
1185struct tlist
1186{
1187 struct tlist *next;
1188 tree expr, writer;
1189};
1190
1191/* Used to implement a cache the results of a call to verify_tree. We only
1192 use this for SAVE_EXPRs. */
1193struct tlist_cache
1194{
1195 struct tlist_cache *next;
1196 struct tlist *cache_before_sp;
1197 struct tlist *cache_after_sp;
1198 tree expr;
1199};
1200
1201/* Obstack to use when allocating tlist structures, and corresponding
1202 firstobj. */
1203static struct obstack tlist_obstack;
1204static char *tlist_firstobj = 0;
1205
1206/* Keep track of the identifiers we've warned about, so we can avoid duplicate
1207 warnings. */
1208static struct tlist *warned_ids;
1209/* SAVE_EXPRs need special treatment. We process them only once and then
1210 cache the results. */
1211static struct tlist_cache *save_expr_cache;
1212
1213static void add_tlist (struct tlist **, struct tlist *, tree, int);
1214static void merge_tlist (struct tlist **, struct tlist *, int);
1215static void verify_tree (tree, struct tlist **, struct tlist **, tree);
1216static int warning_candidate_p (tree);
1217static void warn_for_collisions (struct tlist *);
1218static void warn_for_collisions_1 (tree, tree, struct tlist *, int);
1219static struct tlist *new_tlist (struct tlist *, tree, tree);
1220
1221/* Create a new struct tlist and fill in its fields. */
1222static struct tlist *
1223new_tlist (struct tlist *next, tree t, tree writer)
1224{
1225 struct tlist *l;
1226 l = XOBNEW (&tlist_obstack, struct tlist);
1227 l->next = next;
1228 l->expr = t;
1229 l->writer = writer;
1230 return l;
1231}
1232
1233/* Add duplicates of the nodes found in ADD to the list *TO. If EXCLUDE_WRITER
1234 is nonnull, we ignore any node we find which has a writer equal to it. */
1235
1236static void
1237add_tlist (struct tlist **to, struct tlist *add, tree exclude_writer, int copy)
1238{
1239 while (add)
1240 {
1241 struct tlist *next = add->next;
1242 if (!copy)
1243 add->next = *to;
1244 if (!exclude_writer || add->writer != exclude_writer)
1245 *to = copy ? new_tlist (*to, add->expr, add->writer) : add;
1246 add = next;
1247 }
1248}
1249
1250/* Merge the nodes of ADD into TO. This merging process is done so that for
1251 each variable that already exists in TO, no new node is added; however if
1252 there is a write access recorded in ADD, and an occurrence on TO is only
1253 a read access, then the occurrence in TO will be modified to record the
1254 write. */
1255
1256static void
1257merge_tlist (struct tlist **to, struct tlist *add, int copy)
1258{
1259 struct tlist **end = to;
1260
1261 while (*end)
1262 end = &(*end)->next;
1263
1264 while (add)
1265 {
1266 int found = 0;
1267 struct tlist *tmp2;
1268 struct tlist *next = add->next;
1269
1270 for (tmp2 = *to; tmp2; tmp2 = tmp2->next)
1271 if (tmp2->expr == add->expr)
1272 {
1273 found = 1;
1274 if (!tmp2->writer)
1275 tmp2->writer = add->writer;
1276 }
1277 if (!found)
1278 {
1279 *end = copy ? add : new_tlist (NULL, add->expr, add->writer);
1280 end = &(*end)->next;
1281 *end = 0;
1282 }
1283 add = next;
1284 }
1285}
1286
1287/* WRITTEN is a variable, WRITER is its parent. Warn if any of the variable
1288 references in list LIST conflict with it, excluding reads if ONLY writers
1289 is nonzero. */
1290
1291static void
1292warn_for_collisions_1 (tree written, tree writer, struct tlist *list,
1293 int only_writes)
1294{
1295 struct tlist *tmp;
1296
1297 /* Avoid duplicate warnings. */
1298 for (tmp = warned_ids; tmp; tmp = tmp->next)
1299 if (tmp->expr == written)
1300 return;
1301
1302 while (list)
1303 {
1304 if (list->expr == written
1305 && list->writer != writer
1306 && (!only_writes || list->writer)
1307 && DECL_NAME (list->expr))
1308 {
1309 warned_ids = new_tlist (warned_ids, written, NULL_TREE);
1310 warning (0, "operation on %qE may be undefined", list->expr);
1311 }
1312 list = list->next;
1313 }
1314}
1315
1316/* Given a list LIST of references to variables, find whether any of these
1317 can cause conflicts due to missing sequence points. */
1318
1319static void
1320warn_for_collisions (struct tlist *list)
1321{
1322 struct tlist *tmp;
1323
1324 for (tmp = list; tmp; tmp = tmp->next)
1325 {
1326 if (tmp->writer)
1327 warn_for_collisions_1 (tmp->expr, tmp->writer, list, 0);
1328 }
1329}
1330
1331/* Return nonzero if X is a tree that can be verified by the sequence point
1332 warnings. */
1333static int
1334warning_candidate_p (tree x)
1335{
1336 return TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == PARM_DECL;
1337}
1338
1339/* Walk the tree X, and record accesses to variables. If X is written by the
1340 parent tree, WRITER is the parent.
1341 We store accesses in one of the two lists: PBEFORE_SP, and PNO_SP. If this
1342 expression or its only operand forces a sequence point, then everything up
1343 to the sequence point is stored in PBEFORE_SP. Everything else gets stored
1344 in PNO_SP.
1345 Once we return, we will have emitted warnings if any subexpression before
1346 such a sequence point could be undefined. On a higher level, however, the
1347 sequence point may not be relevant, and we'll merge the two lists.
1348
1349 Example: (b++, a) + b;
1350 The call that processes the COMPOUND_EXPR will store the increment of B
1351 in PBEFORE_SP, and the use of A in PNO_SP. The higher-level call that
1352 processes the PLUS_EXPR will need to merge the two lists so that
1353 eventually, all accesses end up on the same list (and we'll warn about the
1354 unordered subexpressions b++ and b.
1355
1356 A note on merging. If we modify the former example so that our expression
1357 becomes
1358 (b++, b) + a
1359 care must be taken not simply to add all three expressions into the final
1360 PNO_SP list. The function merge_tlist takes care of that by merging the
1361 before-SP list of the COMPOUND_EXPR into its after-SP list in a special
1362 way, so that no more than one access to B is recorded. */
1363
1364static void
1365verify_tree (tree x, struct tlist **pbefore_sp, struct tlist **pno_sp,
1366 tree writer)
1367{
1368 struct tlist *tmp_before, *tmp_nosp, *tmp_list2, *tmp_list3;
1369 enum tree_code code;
1370 enum tree_code_class cl;
1371
1372 /* X may be NULL if it is the operand of an empty statement expression
1373 ({ }). */
1374 if (x == NULL)
1375 return;
1376
1377 restart:
1378 code = TREE_CODE (x);
1379 cl = TREE_CODE_CLASS (code);
1380
1381 if (warning_candidate_p (x))
1382 {
1383 *pno_sp = new_tlist (*pno_sp, x, writer);
1384 return;
1385 }
1386
1387 switch (code)
1388 {
1389 case CONSTRUCTOR:
1390 return;
1391
1392 case COMPOUND_EXPR:
1393 case TRUTH_ANDIF_EXPR:
1394 case TRUTH_ORIF_EXPR:
1395 tmp_before = tmp_nosp = tmp_list3 = 0;
1396 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1397 warn_for_collisions (tmp_nosp);
1398 merge_tlist (pbefore_sp, tmp_before, 0);
1399 merge_tlist (pbefore_sp, tmp_nosp, 0);
1400 verify_tree (TREE_OPERAND (x, 1), &tmp_list3, pno_sp, NULL_TREE);
1401 merge_tlist (pbefore_sp, tmp_list3, 0);
1402 return;
1403
1404 case COND_EXPR:
1405 tmp_before = tmp_list2 = 0;
1406 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_list2, NULL_TREE);
1407 warn_for_collisions (tmp_list2);
1408 merge_tlist (pbefore_sp, tmp_before, 0);
1409 merge_tlist (pbefore_sp, tmp_list2, 1);
1410
1411 tmp_list3 = tmp_nosp = 0;
1412 verify_tree (TREE_OPERAND (x, 1), &tmp_list3, &tmp_nosp, NULL_TREE);
1413 warn_for_collisions (tmp_nosp);
1414 merge_tlist (pbefore_sp, tmp_list3, 0);
1415
1416 tmp_list3 = tmp_list2 = 0;
1417 verify_tree (TREE_OPERAND (x, 2), &tmp_list3, &tmp_list2, NULL_TREE);
1418 warn_for_collisions (tmp_list2);
1419 merge_tlist (pbefore_sp, tmp_list3, 0);
1420 /* Rather than add both tmp_nosp and tmp_list2, we have to merge the
1421 two first, to avoid warning for (a ? b++ : b++). */
1422 merge_tlist (&tmp_nosp, tmp_list2, 0);
1423 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1424 return;
1425
1426 case PREDECREMENT_EXPR:
1427 case PREINCREMENT_EXPR:
1428 case POSTDECREMENT_EXPR:
1429 case POSTINCREMENT_EXPR:
1430 verify_tree (TREE_OPERAND (x, 0), pno_sp, pno_sp, x);
1431 return;
1432
1433 case MODIFY_EXPR:
1434 tmp_before = tmp_nosp = tmp_list3 = 0;
1435 verify_tree (TREE_OPERAND (x, 1), &tmp_before, &tmp_nosp, NULL_TREE);
1436 verify_tree (TREE_OPERAND (x, 0), &tmp_list3, &tmp_list3, x);
1437 /* Expressions inside the LHS are not ordered wrt. the sequence points
1438 in the RHS. Example:
1439 *a = (a++, 2)
1440 Despite the fact that the modification of "a" is in the before_sp
1441 list (tmp_before), it conflicts with the use of "a" in the LHS.
1442 We can handle this by adding the contents of tmp_list3
1443 to those of tmp_before, and redoing the collision warnings for that
1444 list. */
1445 add_tlist (&tmp_before, tmp_list3, x, 1);
1446 warn_for_collisions (tmp_before);
1447 /* Exclude the LHS itself here; we first have to merge it into the
1448 tmp_nosp list. This is done to avoid warning for "a = a"; if we
1449 didn't exclude the LHS, we'd get it twice, once as a read and once
1450 as a write. */
1451 add_tlist (pno_sp, tmp_list3, x, 0);
1452 warn_for_collisions_1 (TREE_OPERAND (x, 0), x, tmp_nosp, 1);
1453
1454 merge_tlist (pbefore_sp, tmp_before, 0);
1455 if (warning_candidate_p (TREE_OPERAND (x, 0)))
1456 merge_tlist (&tmp_nosp, new_tlist (NULL, TREE_OPERAND (x, 0), x), 0);
1457 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 1);
1458 return;
1459
1460 case CALL_EXPR:
1461 /* We need to warn about conflicts among arguments and conflicts between
1462 args and the function address. Side effects of the function address,
1463 however, are not ordered by the sequence point of the call. */
1464 tmp_before = tmp_nosp = tmp_list2 = tmp_list3 = 0;
1465 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1466 if (TREE_OPERAND (x, 1))
1467 verify_tree (TREE_OPERAND (x, 1), &tmp_list2, &tmp_list3, NULL_TREE);
1468 merge_tlist (&tmp_list3, tmp_list2, 0);
1469 add_tlist (&tmp_before, tmp_list3, NULL_TREE, 0);
1470 add_tlist (&tmp_before, tmp_nosp, NULL_TREE, 0);
1471 warn_for_collisions (tmp_before);
1472 add_tlist (pbefore_sp, tmp_before, NULL_TREE, 0);
1473 return;
1474
1475 case TREE_LIST:
1476 /* Scan all the list, e.g. indices of multi dimensional array. */
1477 while (x)
1478 {
1479 tmp_before = tmp_nosp = 0;
1480 verify_tree (TREE_VALUE (x), &tmp_before, &tmp_nosp, NULL_TREE);
1481 merge_tlist (&tmp_nosp, tmp_before, 0);
1482 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1483 x = TREE_CHAIN (x);
1484 }
1485 return;
1486
1487 case SAVE_EXPR:
1488 {
1489 struct tlist_cache *t;
1490 for (t = save_expr_cache; t; t = t->next)
1491 if (t->expr == x)
1492 break;
1493
1494 if (!t)
1495 {
1496 t = XOBNEW (&tlist_obstack, struct tlist_cache);
1497 t->next = save_expr_cache;
1498 t->expr = x;
1499 save_expr_cache = t;
1500
1501 tmp_before = tmp_nosp = 0;
1502 verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1503 warn_for_collisions (tmp_nosp);
1504
1505 tmp_list3 = 0;
1506 while (tmp_nosp)
1507 {
1508 struct tlist *t = tmp_nosp;
1509 tmp_nosp = t->next;
1510 merge_tlist (&tmp_list3, t, 0);
1511 }
1512 t->cache_before_sp = tmp_before;
1513 t->cache_after_sp = tmp_list3;
1514 }
1515 merge_tlist (pbefore_sp, t->cache_before_sp, 1);
1516 add_tlist (pno_sp, t->cache_after_sp, NULL_TREE, 1);
1517 return;
1518 }
1519
1520 default:
1521 /* For other expressions, simply recurse on their operands.
1522 Manual tail recursion for unary expressions.
1523 Other non-expressions need not be processed. */
1524 if (cl == tcc_unary)
1525 {
1526 x = TREE_OPERAND (x, 0);
1527 writer = 0;
1528 goto restart;
1529 }
1530 else if (IS_EXPR_CODE_CLASS (cl))
1531 {
1532 int lp;
1533 int max = TREE_CODE_LENGTH (TREE_CODE (x));
1534 for (lp = 0; lp < max; lp++)
1535 {
1536 tmp_before = tmp_nosp = 0;
1537 verify_tree (TREE_OPERAND (x, lp), &tmp_before, &tmp_nosp, 0);
1538 merge_tlist (&tmp_nosp, tmp_before, 0);
1539 add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1540 }
1541 }
1542 return;
1543 }
1544}
1545
1546/* Try to warn for undefined behavior in EXPR due to missing sequence
1547 points. */
1548
1549void
1550verify_sequence_points (tree expr)
1551{
1552 struct tlist *before_sp = 0, *after_sp = 0;
1553
1554 warned_ids = 0;
1555 save_expr_cache = 0;
1556 if (tlist_firstobj == 0)
1557 {
1558 gcc_obstack_init (&tlist_obstack);
1559 tlist_firstobj = (char *) obstack_alloc (&tlist_obstack, 0);
1560 }
1561
1562 verify_tree (expr, &before_sp, &after_sp, 0);
1563 warn_for_collisions (after_sp);
1564 obstack_free (&tlist_obstack, tlist_firstobj);
1565}
1566
1567/* Validate the expression after `case' and apply default promotions. */
1568
1569static tree
1570check_case_value (tree value)
1571{
1572 if (value == NULL_TREE)
1573 return value;
1574
1575 /* ??? Can we ever get nops here for a valid case value? We
1576 shouldn't for C. */
1577 STRIP_TYPE_NOPS (value);
1578 /* In C++, the following is allowed:
1579
1580 const int i = 3;
1581 switch (...) { case i: ... }
1582
1583 So, we try to reduce the VALUE to a constant that way. */
1584 if (c_dialect_cxx ())
1585 {
1586 value = decl_constant_value (value);
1587 STRIP_TYPE_NOPS (value);
1588 value = fold (value);
1589 }
1590
1591 if (TREE_CODE (value) == INTEGER_CST)
1592 /* Promote char or short to int. */
1593 value = perform_integral_promotions (value);
1594 else if (value != error_mark_node)
1595 {
1596 error ("case label does not reduce to an integer constant");
1597 value = error_mark_node;
1598 }
1599
1600 constant_expression_warning (value);
1601
1602 return value;
1603}
1604
1605/* See if the case values LOW and HIGH are in the range of the original
1606 type (i.e. before the default conversion to int) of the switch testing
1607 expression.
1608 TYPE is the promoted type of the testing expression, and ORIG_TYPE is
1609 the type before promoting it. CASE_LOW_P is a pointer to the lower
1610 bound of the case label, and CASE_HIGH_P is the upper bound or NULL
1611 if the case is not a case range.
1612 The caller has to make sure that we are not called with NULL for
1613 CASE_LOW_P (i.e. the default case).
1614 Returns true if the case label is in range of ORIG_TYPE (saturated or
1615 untouched) or false if the label is out of range. */
1616
1617static bool
1618check_case_bounds (tree type, tree orig_type,
1619 tree *case_low_p, tree *case_high_p)
1620{
1621 tree min_value, max_value;
1622 tree case_low = *case_low_p;
1623 tree case_high = case_high_p ? *case_high_p : case_low;
1624
1625 /* If there was a problem with the original type, do nothing. */
1626 if (orig_type == error_mark_node)
1627 return true;
1628
1629 min_value = TYPE_MIN_VALUE (orig_type);
1630 max_value = TYPE_MAX_VALUE (orig_type);
1631
1632 /* Case label is less than minimum for type. */
1633 if (tree_int_cst_compare (case_low, min_value) < 0
1634 && tree_int_cst_compare (case_high, min_value) < 0)
1635 {
1636 warning (0, "case label value is less than minimum value for type");
1637 return false;
1638 }
1639
1640 /* Case value is greater than maximum for type. */
1641 if (tree_int_cst_compare (case_low, max_value) > 0
1642 && tree_int_cst_compare (case_high, max_value) > 0)
1643 {
1644 warning (0, "case label value exceeds maximum value for type");
1645 return false;
1646 }
1647
1648 /* Saturate lower case label value to minimum. */
1649 if (tree_int_cst_compare (case_high, min_value) >= 0
1650 && tree_int_cst_compare (case_low, min_value) < 0)
1651 {
1652 warning (0, "lower value in case label range"
1653 " less than minimum value for type");
1654 case_low = min_value;
1655 }
1656
1657 /* Saturate upper case label value to maximum. */
1658 if (tree_int_cst_compare (case_low, max_value) <= 0
1659 && tree_int_cst_compare (case_high, max_value) > 0)
1660 {
1661 warning (0, "upper value in case label range"
1662 " exceeds maximum value for type");
1663 case_high = max_value;
1664 }
1665
1666 if (*case_low_p != case_low)
1667 *case_low_p = convert (type, case_low);
1668 if (case_high_p && *case_high_p != case_high)
1669 *case_high_p = convert (type, case_high);
1670
1671 return true;
1672}
1673
1674/* Return an integer type with BITS bits of precision,
1675 that is unsigned if UNSIGNEDP is nonzero, otherwise signed. */
1676
1677tree
1678c_common_type_for_size (unsigned int bits, int unsignedp)
1679{
1680 if (bits == TYPE_PRECISION (integer_type_node))
1681 return unsignedp ? unsigned_type_node : integer_type_node;
1682
1683 if (bits == TYPE_PRECISION (signed_char_type_node))
1684 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1685
1686 if (bits == TYPE_PRECISION (short_integer_type_node))
1687 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1688
1689 if (bits == TYPE_PRECISION (long_integer_type_node))
1690 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1691
1692 if (bits == TYPE_PRECISION (long_long_integer_type_node))
1693 return (unsignedp ? long_long_unsigned_type_node
1694 : long_long_integer_type_node);
1695
1696 if (bits == TYPE_PRECISION (widest_integer_literal_type_node))
1697 return (unsignedp ? widest_unsigned_literal_type_node
1698 : widest_integer_literal_type_node);
1699
1700 if (bits <= TYPE_PRECISION (intQI_type_node))
1701 return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1702
1703 if (bits <= TYPE_PRECISION (intHI_type_node))
1704 return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1705
1706 if (bits <= TYPE_PRECISION (intSI_type_node))
1707 return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1708
1709 if (bits <= TYPE_PRECISION (intDI_type_node))
1710 return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1711
1712 return 0;
1713}
1714
1715/* Used for communication between c_common_type_for_mode and
1716 c_register_builtin_type. */
1717static GTY(()) tree registered_builtin_types;
1718
1719/* Return a data type that has machine mode MODE.
1720 If the mode is an integer,
1721 then UNSIGNEDP selects between signed and unsigned types. */
1722
1723tree
1724c_common_type_for_mode (enum machine_mode mode, int unsignedp)
1725{
1726 tree t;
1727
1728 if (mode == TYPE_MODE (integer_type_node))
1729 return unsignedp ? unsigned_type_node : integer_type_node;
1730
1731 if (mode == TYPE_MODE (signed_char_type_node))
1732 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1733
1734 if (mode == TYPE_MODE (short_integer_type_node))
1735 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1736
1737 if (mode == TYPE_MODE (long_integer_type_node))
1738 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1739
1740 if (mode == TYPE_MODE (long_long_integer_type_node))
1741 return unsignedp ? long_long_unsigned_type_node : long_long_integer_type_node;
1742
1743 if (mode == TYPE_MODE (widest_integer_literal_type_node))
1744 return unsignedp ? widest_unsigned_literal_type_node
1745 : widest_integer_literal_type_node;
1746
1747 if (mode == QImode)
1748 return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1749
1750 if (mode == HImode)
1751 return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1752
1753 if (mode == SImode)
1754 return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1755
1756 if (mode == DImode)
1757 return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1758
1759#if HOST_BITS_PER_WIDE_INT >= 64
1760 if (mode == TYPE_MODE (intTI_type_node))
1761 return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
1762#endif
1763
1764 if (mode == TYPE_MODE (float_type_node))
1765 return float_type_node;
1766
1767 if (mode == TYPE_MODE (double_type_node))
1768 return double_type_node;
1769
1770 if (mode == TYPE_MODE (long_double_type_node))
1771 return long_double_type_node;
1772
1773 if (mode == TYPE_MODE (void_type_node))
1774 return void_type_node;
1775
1776 if (mode == TYPE_MODE (build_pointer_type (char_type_node)))
1777 return (unsignedp
1778 ? make_unsigned_type (GET_MODE_PRECISION (mode))
1779 : make_signed_type (GET_MODE_PRECISION (mode)));
1780
1781 if (mode == TYPE_MODE (build_pointer_type (integer_type_node)))
1782 return (unsignedp
1783 ? make_unsigned_type (GET_MODE_PRECISION (mode))
1784 : make_signed_type (GET_MODE_PRECISION (mode)));
1785
1786 if (COMPLEX_MODE_P (mode))
1787 {
1788 enum machine_mode inner_mode;
1789 tree inner_type;
1790
1791 if (mode == TYPE_MODE (complex_float_type_node))
1792 return complex_float_type_node;
1793 if (mode == TYPE_MODE (complex_double_type_node))
1794 return complex_double_type_node;
1795 if (mode == TYPE_MODE (complex_long_double_type_node))
1796 return complex_long_double_type_node;
1797
1798 if (mode == TYPE_MODE (complex_integer_type_node) && !unsignedp)
1799 return complex_integer_type_node;
1800
1801 inner_mode = GET_MODE_INNER (mode);
1802 inner_type = c_common_type_for_mode (inner_mode, unsignedp);
1803 if (inner_type != NULL_TREE)
1804 return build_complex_type (inner_type);
1805 }
1806 else if (VECTOR_MODE_P (mode))
1807 {
1808 enum machine_mode inner_mode = GET_MODE_INNER (mode);
1809 tree inner_type = c_common_type_for_mode (inner_mode, unsignedp);
1810 if (inner_type != NULL_TREE)
1811 return build_vector_type_for_mode (inner_type, mode);
1812 }
1813
1814 if (mode == TYPE_MODE (dfloat32_type_node))
1815 return dfloat32_type_node;
1816 if (mode == TYPE_MODE (dfloat64_type_node))
1817 return dfloat64_type_node;
1818 if (mode == TYPE_MODE (dfloat128_type_node))
1819 return dfloat128_type_node;
1820
1821 for (t = registered_builtin_types; t; t = TREE_CHAIN (t))
1822 if (TYPE_MODE (TREE_VALUE (t)) == mode)
1823 return TREE_VALUE (t);
1824
1825 return 0;
1826}
1827
1828/* Return an unsigned type the same as TYPE in other respects. */
1829tree
1830c_common_unsigned_type (tree type)
1831{
1832 tree type1 = TYPE_MAIN_VARIANT (type);
1833 if (type1 == signed_char_type_node || type1 == char_type_node)
1834 return unsigned_char_type_node;
1835 if (type1 == integer_type_node)
1836 return unsigned_type_node;
1837 if (type1 == short_integer_type_node)
1838 return short_unsigned_type_node;
1839 if (type1 == long_integer_type_node)
1840 return long_unsigned_type_node;
1841 if (type1 == long_long_integer_type_node)
1842 return long_long_unsigned_type_node;
1843 if (type1 == widest_integer_literal_type_node)
1844 return widest_unsigned_literal_type_node;
1845#if HOST_BITS_PER_WIDE_INT >= 64
1846 if (type1 == intTI_type_node)
1847 return unsigned_intTI_type_node;
1848#endif
1849 if (type1 == intDI_type_node)
1850 return unsigned_intDI_type_node;
1851 if (type1 == intSI_type_node)
1852 return unsigned_intSI_type_node;
1853 if (type1 == intHI_type_node)
1854 return unsigned_intHI_type_node;
1855 if (type1 == intQI_type_node)
1856 return unsigned_intQI_type_node;
1857
1858 return c_common_signed_or_unsigned_type (1, type);
1859}
1860
1861/* Return a signed type the same as TYPE in other respects. */
1862
1863tree
1864c_common_signed_type (tree type)
1865{
1866 tree type1 = TYPE_MAIN_VARIANT (type);
1867 if (type1 == unsigned_char_type_node || type1 == char_type_node)
1868 return signed_char_type_node;
1869 if (type1 == unsigned_type_node)
1870 return integer_type_node;
1871 if (type1 == short_unsigned_type_node)
1872 return short_integer_type_node;
1873 if (type1 == long_unsigned_type_node)
1874 return long_integer_type_node;
1875 if (type1 == long_long_unsigned_type_node)
1876 return long_long_integer_type_node;
1877 if (type1 == widest_unsigned_literal_type_node)
1878 return widest_integer_literal_type_node;
1879#if HOST_BITS_PER_WIDE_INT >= 64
1880 if (type1 == unsigned_intTI_type_node)
1881 return intTI_type_node;
1882#endif
1883 if (type1 == unsigned_intDI_type_node)
1884 return intDI_type_node;
1885 if (type1 == unsigned_intSI_type_node)
1886 return intSI_type_node;
1887 if (type1 == unsigned_intHI_type_node)
1888 return intHI_type_node;
1889 if (type1 == unsigned_intQI_type_node)
1890 return intQI_type_node;
1891
1892 return c_common_signed_or_unsigned_type (0, type);
1893}
1894
1895/* Return a type the same as TYPE except unsigned or
1896 signed according to UNSIGNEDP. */
1897
1898tree
1899c_common_signed_or_unsigned_type (int unsignedp, tree type)
1900{
1901 if (!INTEGRAL_TYPE_P (type)
1902 || TYPE_UNSIGNED (type) == unsignedp)
1903 return type;
1904
1905 /* For ENUMERAL_TYPEs in C++, must check the mode of the types, not
1906 the precision; they have precision set to match their range, but
1907 may use a wider mode to match an ABI. If we change modes, we may
1908 wind up with bad conversions. For INTEGER_TYPEs in C, must check
1909 the precision as well, so as to yield correct results for
1910 bit-field types. C++ does not have these separate bit-field
1911 types, and producing a signed or unsigned variant of an
1912 ENUMERAL_TYPE may cause other problems as well. */
1913
1914#define TYPE_OK(node) \
1915 (TYPE_MODE (type) == TYPE_MODE (node) \
1916 && (c_dialect_cxx () || TYPE_PRECISION (type) == TYPE_PRECISION (node)))
1917 if (TYPE_OK (signed_char_type_node))
1918 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1919 if (TYPE_OK (integer_type_node))
1920 return unsignedp ? unsigned_type_node : integer_type_node;
1921 if (TYPE_OK (short_integer_type_node))
1922 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1923 if (TYPE_OK (long_integer_type_node))
1924 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1925 if (TYPE_OK (long_long_integer_type_node))
1926 return (unsignedp ? long_long_unsigned_type_node
1927 : long_long_integer_type_node);
1928 if (TYPE_OK (widest_integer_literal_type_node))
1929 return (unsignedp ? widest_unsigned_literal_type_node
1930 : widest_integer_literal_type_node);
1931
1932#if HOST_BITS_PER_WIDE_INT >= 64
1933 if (TYPE_OK (intTI_type_node))
1934 return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
1935#endif
1936 if (TYPE_OK (intDI_type_node))
1937 return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
1938 if (TYPE_OK (intSI_type_node))
1939 return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
1940 if (TYPE_OK (intHI_type_node))
1941 return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
1942 if (TYPE_OK (intQI_type_node))
1943 return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
1944#undef TYPE_OK
1945
1946 if (c_dialect_cxx ())
1947 return type;
1948 else
1949 return build_nonstandard_integer_type (TYPE_PRECISION (type), unsignedp);
1950}
1951
1952/* Build a bit-field integer type for the given WIDTH and UNSIGNEDP. */
1953
1954tree
1955c_build_bitfield_integer_type (unsigned HOST_WIDE_INT width, int unsignedp)
1956{
1957 /* Extended integer types of the same width as a standard type have
1958 lesser rank, so those of the same width as int promote to int or
1959 unsigned int and are valid for printf formats expecting int or
1960 unsigned int. To avoid such special cases, avoid creating
1961 extended integer types for bit-fields if a standard integer type
1962 is available. */
1963 if (width == TYPE_PRECISION (integer_type_node))
1964 return unsignedp ? unsigned_type_node : integer_type_node;
1965 if (width == TYPE_PRECISION (signed_char_type_node))
1966 return unsignedp ? unsigned_char_type_node : signed_char_type_node;
1967 if (width == TYPE_PRECISION (short_integer_type_node))
1968 return unsignedp ? short_unsigned_type_node : short_integer_type_node;
1969 if (width == TYPE_PRECISION (long_integer_type_node))
1970 return unsignedp ? long_unsigned_type_node : long_integer_type_node;
1971 if (width == TYPE_PRECISION (long_long_integer_type_node))
1972 return (unsignedp ? long_long_unsigned_type_node
1973 : long_long_integer_type_node);
1974 return build_nonstandard_integer_type (width, unsignedp);
1975}
1976
1977/* The C version of the register_builtin_type langhook. */
1978
1979void
1980c_register_builtin_type (tree type, const char* name)
1981{
1982 tree decl;
1983
1984 decl = build_decl (TYPE_DECL, get_identifier (name), type);
1985 DECL_ARTIFICIAL (decl) = 1;
1986 if (!TYPE_NAME (type))
1987 TYPE_NAME (type) = decl;
1988 pushdecl (decl);
1989
1990 registered_builtin_types = tree_cons (0, type, registered_builtin_types);
1991}
1992
1993
1994/* Return the minimum number of bits needed to represent VALUE in a
1995 signed or unsigned type, UNSIGNEDP says which. */
1996
1997unsigned int
1998min_precision (tree value, int unsignedp)
1999{
2000 int log;
2001
2002 /* If the value is negative, compute its negative minus 1. The latter
2003 adjustment is because the absolute value of the largest negative value
2004 is one larger than the largest positive value. This is equivalent to
2005 a bit-wise negation, so use that operation instead. */
2006
2007 if (tree_int_cst_sgn (value) < 0)
2008 value = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (value), value);
2009
2010 /* Return the number of bits needed, taking into account the fact
2011 that we need one more bit for a signed than unsigned type. */
2012
2013 if (integer_zerop (value))
2014 log = 0;
2015 else
2016 log = tree_floor_log2 (value);
2017
2018 return log + 1 + !unsignedp;
2019}
2020
2021/* Print an error message for invalid operands to arith operation
2022 CODE with TYPE0 for operand 0, and TYPE1 for operand 1. */
2023
2024void
2025binary_op_error (enum tree_code code, tree type0, tree type1)
2026{
2027 const char *opname;
2028
2029 switch (code)
2030 {
2031 case PLUS_EXPR:
2032 opname = "+"; break;
2033 case MINUS_EXPR:
2034 opname = "-"; break;
2035 case MULT_EXPR:
2036 opname = "*"; break;
2037 case MAX_EXPR:
2038 opname = "max"; break;
2039 case MIN_EXPR:
2040 opname = "min"; break;
2041 case EQ_EXPR:
2042 opname = "=="; break;
2043 case NE_EXPR:
2044 opname = "!="; break;
2045 case LE_EXPR:
2046 opname = "<="; break;
2047 case GE_EXPR:
2048 opname = ">="; break;
2049 case LT_EXPR:
2050 opname = "<"; break;
2051 case GT_EXPR:
2052 opname = ">"; break;
2053 case LSHIFT_EXPR:
2054 opname = "<<"; break;
2055 case RSHIFT_EXPR:
2056 opname = ">>"; break;
2057 case TRUNC_MOD_EXPR:
2058 case FLOOR_MOD_EXPR:
2059 opname = "%"; break;
2060 case TRUNC_DIV_EXPR:
2061 case FLOOR_DIV_EXPR:
2062 opname = "/"; break;
2063 case BIT_AND_EXPR:
2064 opname = "&"; break;
2065 case BIT_IOR_EXPR:
2066 opname = "|"; break;
2067 case TRUTH_ANDIF_EXPR:
2068 opname = "&&"; break;
2069 case TRUTH_ORIF_EXPR:
2070 opname = "||"; break;
2071 case BIT_XOR_EXPR:
2072 opname = "^"; break;
2073 default:
2074 gcc_unreachable ();
2075 }
2076 error ("invalid operands to binary %s (have %qT and %qT)", opname,
2077 type0, type1);
2078}
2079
2080/* Subroutine of build_binary_op, used for comparison operations.
2081 See if the operands have both been converted from subword integer types
2082 and, if so, perhaps change them both back to their original type.
2083 This function is also responsible for converting the two operands
2084 to the proper common type for comparison.
2085
2086 The arguments of this function are all pointers to local variables
2087 of build_binary_op: OP0_PTR is &OP0, OP1_PTR is &OP1,
2088 RESTYPE_PTR is &RESULT_TYPE and RESCODE_PTR is &RESULTCODE.
2089
2090 If this function returns nonzero, it means that the comparison has
2091 a constant value. What this function returns is an expression for
2092 that value. */
2093
2094tree
2095shorten_compare (tree *op0_ptr, tree *op1_ptr, tree *restype_ptr,
2096 enum tree_code *rescode_ptr)
2097{
2098 tree type;
2099 tree op0 = *op0_ptr;
2100 tree op1 = *op1_ptr;
2101 int unsignedp0, unsignedp1;
2102 int real1, real2;
2103 tree primop0, primop1;
2104 enum tree_code code = *rescode_ptr;
2105
2106 /* Throw away any conversions to wider types
2107 already present in the operands. */
2108
2109 primop0 = get_narrower (op0, &unsignedp0);
2110 primop1 = get_narrower (op1, &unsignedp1);
2111
2112 /* Handle the case that OP0 does not *contain* a conversion
2113 but it *requires* conversion to FINAL_TYPE. */
2114
2115 if (op0 == primop0 && TREE_TYPE (op0) != *restype_ptr)
2116 unsignedp0 = TYPE_UNSIGNED (TREE_TYPE (op0));
2117 if (op1 == primop1 && TREE_TYPE (op1) != *restype_ptr)
2118 unsignedp1 = TYPE_UNSIGNED (TREE_TYPE (op1));
2119
2120 /* If one of the operands must be floated, we cannot optimize. */
2121 real1 = TREE_CODE (TREE_TYPE (primop0)) == REAL_TYPE;
2122 real2 = TREE_CODE (TREE_TYPE (primop1)) == REAL_TYPE;
2123
2124 /* If first arg is constant, swap the args (changing operation
2125 so value is preserved), for canonicalization. Don't do this if
2126 the second arg is 0. */
2127
2128 if (TREE_CONSTANT (primop0)
2129 && !integer_zerop (primop1) && !real_zerop (primop1))
2130 {
2131 tree tem = primop0;
2132 int temi = unsignedp0;
2133 primop0 = primop1;
2134 primop1 = tem;
2135 tem = op0;
2136 op0 = op1;
2137 op1 = tem;
2138 *op0_ptr = op0;
2139 *op1_ptr = op1;
2140 unsignedp0 = unsignedp1;
2141 unsignedp1 = temi;
2142 temi = real1;
2143 real1 = real2;
2144 real2 = temi;
2145
2146 switch (code)
2147 {
2148 case LT_EXPR:
2149 code = GT_EXPR;
2150 break;
2151 case GT_EXPR:
2152 code = LT_EXPR;
2153 break;
2154 case LE_EXPR:
2155 code = GE_EXPR;
2156 break;
2157 case GE_EXPR:
2158 code = LE_EXPR;
2159 break;
2160 default:
2161 break;
2162 }
2163 *rescode_ptr = code;
2164 }
2165
2166 /* If comparing an integer against a constant more bits wide,
2167 maybe we can deduce a value of 1 or 0 independent of the data.
2168 Or else truncate the constant now
2169 rather than extend the variable at run time.
2170
2171 This is only interesting if the constant is the wider arg.
2172 Also, it is not safe if the constant is unsigned and the
2173 variable arg is signed, since in this case the variable
2174 would be sign-extended and then regarded as unsigned.
2175 Our technique fails in this case because the lowest/highest
2176 possible unsigned results don't follow naturally from the
2177 lowest/highest possible values of the variable operand.
2178 For just EQ_EXPR and NE_EXPR there is another technique that
2179 could be used: see if the constant can be faithfully represented
2180 in the other operand's type, by truncating it and reextending it
2181 and see if that preserves the constant's value. */
2182
2183 if (!real1 && !real2
2184 && TREE_CODE (primop1) == INTEGER_CST
2185 && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr))
2186 {
2187 int min_gt, max_gt, min_lt, max_lt;
2188 tree maxval, minval;
2189 /* 1 if comparison is nominally unsigned. */
2190 int unsignedp = TYPE_UNSIGNED (*restype_ptr);
2191 tree val;
2192
2193 type = c_common_signed_or_unsigned_type (unsignedp0,
2194 TREE_TYPE (primop0));
2195
2196 maxval = TYPE_MAX_VALUE (type);
2197 minval = TYPE_MIN_VALUE (type);
2198
2199 if (unsignedp && !unsignedp0)
2200 *restype_ptr = c_common_signed_type (*restype_ptr);
2201
2202 if (TREE_TYPE (primop1) != *restype_ptr)
2203 {
2204 /* Convert primop1 to target type, but do not introduce
2205 additional overflow. We know primop1 is an int_cst. */
2206 tree tmp = build_int_cst_wide (*restype_ptr,
2207 TREE_INT_CST_LOW (primop1),
2208 TREE_INT_CST_HIGH (primop1));
2209
2210 primop1 = force_fit_type (tmp, 0, TREE_OVERFLOW (primop1),
2211 TREE_CONSTANT_OVERFLOW (primop1));
2212 }
2213 if (type != *restype_ptr)
2214 {
2215 minval = convert (*restype_ptr, minval);
2216 maxval = convert (*restype_ptr, maxval);
2217 }
2218
2219 if (unsignedp && unsignedp0)
2220 {
2221 min_gt = INT_CST_LT_UNSIGNED (primop1, minval);
2222 max_gt = INT_CST_LT_UNSIGNED (primop1, maxval);
2223 min_lt = INT_CST_LT_UNSIGNED (minval, primop1);
2224 max_lt = INT_CST_LT_UNSIGNED (maxval, primop1);
2225 }
2226 else
2227 {
2228 min_gt = INT_CST_LT (primop1, minval);
2229 max_gt = INT_CST_LT (primop1, maxval);
2230 min_lt = INT_CST_LT (minval, primop1);
2231 max_lt = INT_CST_LT (maxval, primop1);
2232 }
2233
2234 val = 0;
2235 /* This used to be a switch, but Genix compiler can't handle that. */
2236 if (code == NE_EXPR)
2237 {
2238 if (max_lt || min_gt)
2239 val = truthvalue_true_node;
2240 }
2241 else if (code == EQ_EXPR)
2242 {
2243 if (max_lt || min_gt)
2244 val = truthvalue_false_node;
2245 }
2246 else if (code == LT_EXPR)
2247 {
2248 if (max_lt)
2249 val = truthvalue_true_node;
2250 if (!min_lt)
2251 val = truthvalue_false_node;
2252 }
2253 else if (code == GT_EXPR)
2254 {
2255 if (min_gt)
2256 val = truthvalue_true_node;
2257 if (!max_gt)
2258 val = truthvalue_false_node;
2259 }
2260 else if (code == LE_EXPR)
2261 {
2262 if (!max_gt)
2263 val = truthvalue_true_node;
2264 if (min_gt)
2265 val = truthvalue_false_node;
2266 }
2267 else if (code == GE_EXPR)
2268 {
2269 if (!min_lt)
2270 val = truthvalue_true_node;
2271 if (max_lt)
2272 val = truthvalue_false_node;
2273 }
2274
2275 /* If primop0 was sign-extended and unsigned comparison specd,
2276 we did a signed comparison above using the signed type bounds.
2277 But the comparison we output must be unsigned.
2278
2279 Also, for inequalities, VAL is no good; but if the signed
2280 comparison had *any* fixed result, it follows that the
2281 unsigned comparison just tests the sign in reverse
2282 (positive values are LE, negative ones GE).
2283 So we can generate an unsigned comparison
2284 against an extreme value of the signed type. */
2285
2286 if (unsignedp && !unsignedp0)
2287 {
2288 if (val != 0)
2289 switch (code)
2290 {
2291 case LT_EXPR:
2292 case GE_EXPR:
2293 primop1 = TYPE_MIN_VALUE (type);
2294 val = 0;
2295 break;
2296
2297 case LE_EXPR:
2298 case GT_EXPR:
2299 primop1 = TYPE_MAX_VALUE (type);
2300 val = 0;
2301 break;
2302
2303 default:
2304 break;
2305 }
2306 type = c_common_unsigned_type (type);
2307 }
2308
2309 if (TREE_CODE (primop0) != INTEGER_CST)
2310 {
2311 if (val == truthvalue_false_node)
2312 warning (0, "comparison is always false due to limited range of data type");
2313 if (val == truthvalue_true_node)
2314 warning (0, "comparison is always true due to limited range of data type");
2315 }
2316
2317 if (val != 0)
2318 {
2319 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
2320 if (TREE_SIDE_EFFECTS (primop0))
2321 return build2 (COMPOUND_EXPR, TREE_TYPE (val), primop0, val);
2322 return val;
2323 }
2324
2325 /* Value is not predetermined, but do the comparison
2326 in the type of the operand that is not constant.
2327 TYPE is already properly set. */
2328 }
2329
2330 /* If either arg is decimal float and the other is float, find the
2331 proper common type to use for comparison. */
2332 else if (real1 && real2
2333 && (DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop0)))
2334 || DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop1)))))
2335 type = common_type (TREE_TYPE (primop0), TREE_TYPE (primop1));
2336
2337 else if (real1 && real2
2338 && (TYPE_PRECISION (TREE_TYPE (primop0))
2339 == TYPE_PRECISION (TREE_TYPE (primop1))))
2340 type = TREE_TYPE (primop0);
2341
2342 /* If args' natural types are both narrower than nominal type
2343 and both extend in the same manner, compare them
2344 in the type of the wider arg.
2345 Otherwise must actually extend both to the nominal
2346 common type lest different ways of extending
2347 alter the result.
2348 (eg, (short)-1 == (unsigned short)-1 should be 0.) */
2349
2350 else if (unsignedp0 == unsignedp1 && real1 == real2
2351 && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr)
2352 && TYPE_PRECISION (TREE_TYPE (primop1)) < TYPE_PRECISION (*restype_ptr))
2353 {
2354 type = common_type (TREE_TYPE (primop0), TREE_TYPE (primop1));
2355 type = c_common_signed_or_unsigned_type (unsignedp0
2356 || TYPE_UNSIGNED (*restype_ptr),
2357 type);
2358 /* Make sure shorter operand is extended the right way
2359 to match the longer operand. */
2360 primop0
2361 = convert (c_common_signed_or_unsigned_type (unsignedp0,
2362 TREE_TYPE (primop0)),
2363 primop0);
2364 primop1
2365 = convert (c_common_signed_or_unsigned_type (unsignedp1,
2366 TREE_TYPE (primop1)),
2367 primop1);
2368 }
2369 else
2370 {
2371 /* Here we must do the comparison on the nominal type
2372 using the args exactly as we received them. */
2373 type = *restype_ptr;
2374 primop0 = op0;
2375 primop1 = op1;
2376
2377 if (!real1 && !real2 && integer_zerop (primop1)
2378 && TYPE_UNSIGNED (*restype_ptr))
2379 {
2380 tree value = 0;
2381 switch (code)
2382 {
2383 case GE_EXPR:
2384 /* All unsigned values are >= 0, so we warn if extra warnings
2385 are requested. However, if OP0 is a constant that is
2386 >= 0, the signedness of the comparison isn't an issue,
2387 so suppress the warning. */
2388 if (extra_warnings && !in_system_header
2389 && !(TREE_CODE (primop0) == INTEGER_CST
2390 && !TREE_OVERFLOW (convert (c_common_signed_type (type),
2391 primop0))))
2392 warning (0, "comparison of unsigned expression >= 0 is always true");
2393 value = truthvalue_true_node;
2394 break;
2395
2396 case LT_EXPR:
2397 if (extra_warnings && !in_system_header
2398 && !(TREE_CODE (primop0) == INTEGER_CST
2399 && !TREE_OVERFLOW (convert (c_common_signed_type (type),
2400 primop0))))
2401 warning (0, "comparison of unsigned expression < 0 is always false");
2402 value = truthvalue_false_node;
2403 break;
2404
2405 default:
2406 break;
2407 }
2408
2409 if (value != 0)
2410 {
2411 /* Don't forget to evaluate PRIMOP0 if it has side effects. */
2412 if (TREE_SIDE_EFFECTS (primop0))
2413 return build2 (COMPOUND_EXPR, TREE_TYPE (value),
2414 primop0, value);
2415 return value;
2416 }
2417 }
2418 }
2419
2420 *op0_ptr = convert (type, primop0);
2421 *op1_ptr = convert (type, primop1);
2422
2423 *restype_ptr = truthvalue_type_node;
2424
2425 return 0;
2426}
2427
2428/* Return a tree for the sum or difference (RESULTCODE says which)
2429 of pointer PTROP and integer INTOP. */
2430
2431tree
2432pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
2433{
2434 tree size_exp, ret;
2435
2436 /* The result is a pointer of the same type that is being added. */
2437
2438 tree result_type = TREE_TYPE (ptrop);
2439
2440 if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
2441 {
2442 if (pedantic || warn_pointer_arith)
2443 pedwarn ("pointer of type %<void *%> used in arithmetic");
2444 size_exp = integer_one_node;
2445 }
2446 else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
2447 {
2448 if (pedantic || warn_pointer_arith)
2449 pedwarn ("pointer to a function used in arithmetic");
2450 size_exp = integer_one_node;
2451 }
2452 else if (TREE_CODE (TREE_TYPE (result_type)) == METHOD_TYPE)
2453 {
2454 if (pedantic || warn_pointer_arith)
2455 pedwarn ("pointer to member function used in arithmetic");
2456 size_exp = integer_one_node;
2457 }
2458 else
2459 size_exp = size_in_bytes (TREE_TYPE (result_type));
2460
2461 /* We are manipulating pointer values, so we don't need to warn
2462 about relying on undefined signed overflow. We disable the
2463 warning here because we use integer types so fold won't know that
2464 they are really pointers. */
2465 fold_defer_overflow_warnings ();
2466
2467 /* If what we are about to multiply by the size of the elements
2468 contains a constant term, apply distributive law
2469 and multiply that constant term separately.
2470 This helps produce common subexpressions. */
2471
2472 if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
2473 && !TREE_CONSTANT (intop)
2474 && TREE_CONSTANT (TREE_OPERAND (intop, 1))
2475 && TREE_CONSTANT (size_exp)
2476 /* If the constant comes from pointer subtraction,
2477 skip this optimization--it would cause an error. */
2478 && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
2479 /* If the constant is unsigned, and smaller than the pointer size,
2480 then we must skip this optimization. This is because it could cause
2481 an overflow error if the constant is negative but INTOP is not. */
2482 && (!TYPE_UNSIGNED (TREE_TYPE (intop))
2483 || (TYPE_PRECISION (TREE_TYPE (intop))
2484 == TYPE_PRECISION (TREE_TYPE (ptrop)))))
2485 {
2486 enum tree_code subcode = resultcode;
2487 tree int_type = TREE_TYPE (intop);
2488 if (TREE_CODE (intop) == MINUS_EXPR)
2489 subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
2490 /* Convert both subexpression types to the type of intop,
2491 because weird cases involving pointer arithmetic
2492 can result in a sum or difference with different type args. */
2493 ptrop = build_binary_op (subcode, ptrop,
2494 convert (int_type, TREE_OPERAND (intop, 1)), 1);
2495 intop = convert (int_type, TREE_OPERAND (intop, 0));
2496 }
2497
2498 /* Convert the integer argument to a type the same size as sizetype
2499 so the multiply won't overflow spuriously. */
2500
2501 if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
2502 || TYPE_UNSIGNED (TREE_TYPE (intop)) != TYPE_UNSIGNED (sizetype))
2503 intop = convert (c_common_type_for_size (TYPE_PRECISION (sizetype),
2504 TYPE_UNSIGNED (sizetype)), intop);
2505
2506 /* Replace the integer argument with a suitable product by the object size.
2507 Do this multiplication as signed, then convert to the appropriate
2508 pointer type (actually unsigned integral). */
2509
2510 intop = convert (result_type,
2511 build_binary_op (MULT_EXPR, intop,
2512 convert (TREE_TYPE (intop), size_exp), 1));
2513
2514 /* Create the sum or difference. */
2515 ret = fold_build2 (resultcode, result_type, ptrop, intop);
2516
2517 fold_undefer_and_ignore_overflow_warnings ();
2518
2519 return ret;
2520}
2521
2522/* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
2523 or for an `if' or `while' statement or ?..: exp. It should already
2524 have been validated to be of suitable type; otherwise, a bad
2525 diagnostic may result.
2526
2527 This preparation consists of taking the ordinary
2528 representation of an expression expr and producing a valid tree
2529 boolean expression describing whether expr is nonzero. We could
2530 simply always do build_binary_op (NE_EXPR, expr, truthvalue_false_node, 1),
2531 but we optimize comparisons, &&, ||, and !.
2532
2533 The resulting type should always be `truthvalue_type_node'. */
2534
2535tree
2536c_common_truthvalue_conversion (tree expr)
2537{
2538 switch (TREE_CODE (expr))
2539 {
2540 case EQ_EXPR: case NE_EXPR: case UNEQ_EXPR: case LTGT_EXPR:
2541 case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR:
2542 case UNLE_EXPR: case UNGE_EXPR: case UNLT_EXPR: case UNGT_EXPR:
2543 case ORDERED_EXPR: case UNORDERED_EXPR:
2544 if (TREE_TYPE (expr) == truthvalue_type_node)
2545 return expr;
2546 return build2 (TREE_CODE (expr), truthvalue_type_node,
2547 TREE_OPERAND (expr, 0), TREE_OPERAND (expr, 1));
2548
2549 case TRUTH_ANDIF_EXPR:
2550 case TRUTH_ORIF_EXPR:
2551 case TRUTH_AND_EXPR:
2552 case TRUTH_OR_EXPR:
2553 case TRUTH_XOR_EXPR:
2554 if (TREE_TYPE (expr) == truthvalue_type_node)
2555 return expr;
2556 return build2 (TREE_CODE (expr), truthvalue_type_node,
2557 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)),
2558 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1)));
2559
2560 case TRUTH_NOT_EXPR:
2561 if (TREE_TYPE (expr) == truthvalue_type_node)
2562 return expr;
2563 return build1 (TREE_CODE (expr), truthvalue_type_node,
2564 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)));
2565
2566 case ERROR_MARK:
2567 return expr;
2568
2569 case INTEGER_CST:
2570 /* Avoid integer_zerop to ignore TREE_CONSTANT_OVERFLOW. */
2571 return (TREE_INT_CST_LOW (expr) != 0 || TREE_INT_CST_HIGH (expr) != 0)
2572 ? truthvalue_true_node
2573 : truthvalue_false_node;
2574
2575 case REAL_CST:
2576 return real_compare (NE_EXPR, &TREE_REAL_CST (expr), &dconst0)
2577 ? truthvalue_true_node
2578 : truthvalue_false_node;
2579
2580 case FUNCTION_DECL:
2581 expr = build_unary_op (ADDR_EXPR, expr, 0);
2582 /* Fall through. */
2583
2584 case ADDR_EXPR:
2585 {
2586 tree inner = TREE_OPERAND (expr, 0);
2587 if (DECL_P (inner)
2588 && (TREE_CODE (inner) == PARM_DECL
2589 || TREE_CODE (inner) == LABEL_DECL
2590 || !DECL_WEAK (inner)))
2591 {
2592 /* Common Ada/Pascal programmer's mistake. We always warn
2593 about this since it is so bad. */
2594 warning (OPT_Waddress,
2595 "the address of %qD will always evaluate as %<true%>",
2596 inner);
2597 return truthvalue_true_node;
2598 }
2599
2600 /* If we are taking the address of an external decl, it might be
2601 zero if it is weak, so we cannot optimize. */
2602 if (DECL_P (inner)
2603 && DECL_EXTERNAL (inner))
2604 break;
2605
2606 if (TREE_SIDE_EFFECTS (inner))
2607 return build2 (COMPOUND_EXPR, truthvalue_type_node,
2608 inner, truthvalue_true_node);
2609 else
2610 return truthvalue_true_node;
2611 }
2612
2613 case COMPLEX_EXPR:
2614 return build_binary_op ((TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1))
2615 ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
2616 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)),
2617 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1)),
2618 0);
2619
2620 case NEGATE_EXPR:
2621 case ABS_EXPR:
2622 case FLOAT_EXPR:
2623 /* These don't change whether an object is nonzero or zero. */
2624 return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0));
2625
2626 case LROTATE_EXPR:
2627 case RROTATE_EXPR:
2628 /* These don't change whether an object is zero or nonzero, but
2629 we can't ignore them if their second arg has side-effects. */
2630 if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
2631 return build2 (COMPOUND_EXPR, truthvalue_type_node,
2632 TREE_OPERAND (expr, 1),
2633 c_common_truthvalue_conversion (TREE_OPERAND (expr, 0)));
2634 else
2635 return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0));
2636
2637 case COND_EXPR:
2638 /* Distribute the conversion into the arms of a COND_EXPR. */
2639 return fold_build3 (COND_EXPR, truthvalue_type_node,
2640 TREE_OPERAND (expr, 0),
2641 c_common_truthvalue_conversion (TREE_OPERAND (expr, 1)),
2642 c_common_truthvalue_conversion (TREE_OPERAND (expr, 2)));
2643
2644 case CONVERT_EXPR:
2645 case NOP_EXPR:
2646 /* Don't cancel the effect of a CONVERT_EXPR from a REFERENCE_TYPE,
2647 since that affects how `default_conversion' will behave. */
2648 if (TREE_CODE (TREE_TYPE (expr)) == REFERENCE_TYPE
2649 || TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == REFERENCE_TYPE)
2650 break;
2651 /* If this is widening the argument, we can ignore it. */
2652 if (TYPE_PRECISION (TREE_TYPE (expr))
2653 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (expr, 0))))
2654 return c_common_truthvalue_conversion (TREE_OPERAND (expr, 0));
2655 break;
2656
2657 case MODIFY_EXPR:
2658 if (!TREE_NO_WARNING (expr)
2659 && warn_parentheses)
2660 {
2661 warning (OPT_Wparentheses,
2662 "suggest parentheses around assignment used as truth value");
2663 TREE_NO_WARNING (expr) = 1;
2664 }
2665 break;
2666
2667 default:
2668 break;
2669 }
2670
2671 if (TREE_CODE (TREE_TYPE (expr)) == COMPLEX_TYPE)
2672 {
2673 tree t = save_expr (expr);
2674 return (build_binary_op
2675 ((TREE_SIDE_EFFECTS (expr)
2676 ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
2677 c_common_truthvalue_conversion (build_unary_op (REALPART_EXPR, t, 0)),
2678 c_common_truthvalue_conversion (build_unary_op (IMAGPART_EXPR, t, 0)),
2679 0));
2680 }
2681
2682 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
2683}
2684
2685static void def_builtin_1 (enum built_in_function fncode,
2686 const char *name,
2687 enum built_in_class fnclass,
2688 tree fntype, tree libtype,
2689 bool both_p, bool fallback_p, bool nonansi_p,
2690 tree fnattrs, bool implicit_p);
2691
2692/* Make a variant type in the proper way for C/C++, propagating qualifiers
2693 down to the element type of an array. */
2694
2695tree
2696c_build_qualified_type (tree type, int type_quals)
2697{
2698 if (type == error_mark_node)
2699 return type;
2700
2701 if (TREE_CODE (type) == ARRAY_TYPE)
2702 {
2703 tree t;
2704 tree element_type = c_build_qualified_type (TREE_TYPE (type),
2705 type_quals);
2706
2707 /* See if we already have an identically qualified type. */
2708 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
2709 {
2710 if (TYPE_QUALS (strip_array_types (t)) == type_quals
2711 && TYPE_NAME (t) == TYPE_NAME (type)
2712 && TYPE_CONTEXT (t) == TYPE_CONTEXT (type)
2713 && attribute_list_equal (TYPE_ATTRIBUTES (t),
2714 TYPE_ATTRIBUTES (type)))
2715 break;
2716 }
2717 if (!t)
2718 {
2719 t = build_variant_type_copy (type);
2720 TREE_TYPE (t) = element_type;
2721 }
2722 return t;
2723 }
2724
2725 /* A restrict-qualified pointer type must be a pointer to object or
2726 incomplete type. Note that the use of POINTER_TYPE_P also allows
2727 REFERENCE_TYPEs, which is appropriate for C++. */
2728 if ((type_quals & TYPE_QUAL_RESTRICT)
2729 && (!POINTER_TYPE_P (type)
2730 || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type))))
2731 {
2732 error ("invalid use of %<restrict%>");
2733 type_quals &= ~TYPE_QUAL_RESTRICT;
2734 }
2735
2736 return build_qualified_type (type, type_quals);
2737}
2738
2739/* Apply the TYPE_QUALS to the new DECL. */
2740
2741void
2742c_apply_type_quals_to_decl (int type_quals, tree decl)
2743{
2744 tree type = TREE_TYPE (decl);
2745
2746 if (type == error_mark_node)
2747 return;
2748
2749 if (((type_quals & TYPE_QUAL_CONST)
2750 || (type && TREE_CODE (type) == REFERENCE_TYPE))
2751 /* An object declared 'const' is only readonly after it is
2752 initialized. We don't have any way of expressing this currently,
2753 so we need to be conservative and unset TREE_READONLY for types
2754 with constructors. Otherwise aliasing code will ignore stores in
2755 an inline constructor. */
2756 && !(type && TYPE_NEEDS_CONSTRUCTING (type)))
2757 TREE_READONLY (decl) = 1;
2758 if (type_quals & TYPE_QUAL_VOLATILE)
2759 {
2760 TREE_SIDE_EFFECTS (decl) = 1;
2761 TREE_THIS_VOLATILE (decl) = 1;
2762 }
2763 if (type_quals & TYPE_QUAL_RESTRICT)
2764 {
2765 while (type && TREE_CODE (type) == ARRAY_TYPE)
2766 /* Allow 'restrict' on arrays of pointers.
2767 FIXME currently we just ignore it. */
2768 type = TREE_TYPE (type);
2769 if (!type
2770 || !POINTER_TYPE_P (type)
2771 || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type)))
2772 error ("invalid use of %<restrict%>");
2773 else if (flag_strict_aliasing && type == TREE_TYPE (decl))
2774 /* Indicate we need to make a unique alias set for this pointer.
2775 We can't do it here because it might be pointing to an
2776 incomplete type. */
2777 DECL_POINTER_ALIAS_SET (decl) = -2;
2778 }
2779}
2780
2781/* Hash function for the problem of multiple type definitions in
2782 different files. This must hash all types that will compare
2783 equal via comptypes to the same value. In practice it hashes
2784 on some of the simple stuff and leaves the details to comptypes. */
2785
2786static hashval_t
2787c_type_hash (const void *p)
2788{
2789 int i = 0;
2790 int shift, size;
2791 tree t = (tree) p;
2792 tree t2;
2793 switch (TREE_CODE (t))
2794 {
2795 /* For pointers, hash on pointee type plus some swizzling. */
2796 case POINTER_TYPE:
2797 return c_type_hash (TREE_TYPE (t)) ^ 0x3003003;
2798 /* Hash on number of elements and total size. */
2799 case ENUMERAL_TYPE:
2800 shift = 3;
2801 t2 = TYPE_VALUES (t);
2802 break;
2803 case RECORD_TYPE:
2804 shift = 0;
2805 t2 = TYPE_FIELDS (t);
2806 break;
2807 case QUAL_UNION_TYPE:
2808 shift = 1;
2809 t2 = TYPE_FIELDS (t);
2810 break;
2811 case UNION_TYPE:
2812 shift = 2;
2813 t2 = TYPE_FIELDS (t);
2814 break;
2815 default:
2816 gcc_unreachable ();
2817 }
2818 for (; t2; t2 = TREE_CHAIN (t2))
2819 i++;
2820 size = TREE_INT_CST_LOW (TYPE_SIZE (t));
2821 return ((size << 24) | (i << shift));
2822}
2823
2824static GTY((param_is (union tree_node))) htab_t type_hash_table;
2825
2826/* Return the typed-based alias set for T, which may be an expression
2827 or a type. Return -1 if we don't do anything special. */
2828
2829HOST_WIDE_INT
2830c_common_get_alias_set (tree t)
2831{
2832 tree u;
2833 PTR *slot;
2834
2835 /* Permit type-punning when accessing a union, provided the access
2836 is directly through the union. For example, this code does not
2837 permit taking the address of a union member and then storing
2838 through it. Even the type-punning allowed here is a GCC
2839 extension, albeit a common and useful one; the C standard says
2840 that such accesses have implementation-defined behavior. */
2841 for (u = t;
2842 TREE_CODE (u) == COMPONENT_REF || TREE_CODE (u) == ARRAY_REF;
2843 u = TREE_OPERAND (u, 0))
2844 if (TREE_CODE (u) == COMPONENT_REF
2845 && TREE_CODE (TREE_TYPE (TREE_OPERAND (u, 0))) == UNION_TYPE)
2846 return 0;
2847
2848 /* That's all the expressions we handle specially. */
2849 if (!TYPE_P (t))
2850 return -1;
2851
2852 /* The C standard guarantees that any object may be accessed via an
2853 lvalue that has character type. */
2854 if (t == char_type_node
2855 || t == signed_char_type_node
2856 || t == unsigned_char_type_node)
2857 return 0;
2858
2859 /* If it has the may_alias attribute, it can alias anything. */
2860 if (lookup_attribute ("may_alias", TYPE_ATTRIBUTES (t)))
2861 return 0;
2862
2863 /* The C standard specifically allows aliasing between signed and
2864 unsigned variants of the same type. We treat the signed
2865 variant as canonical. */
2866 if (TREE_CODE (t) == INTEGER_TYPE && TYPE_UNSIGNED (t))
2867 {
2868 tree t1 = c_common_signed_type (t);
2869
2870 /* t1 == t can happen for boolean nodes which are always unsigned. */
2871 if (t1 != t)
2872 return get_alias_set (t1);
2873 }
2874 else if (POINTER_TYPE_P (t))
2875 {
2876 tree t1;
2877
2878 /* Unfortunately, there is no canonical form of a pointer type.
2879 In particular, if we have `typedef int I', then `int *', and
2880 `I *' are different types. So, we have to pick a canonical
2881 representative. We do this below.
2882
2883 Technically, this approach is actually more conservative that
2884 it needs to be. In particular, `const int *' and `int *'
2885 should be in different alias sets, according to the C and C++
2886 standard, since their types are not the same, and so,
2887 technically, an `int **' and `const int **' cannot point at
2888 the same thing.
2889
2890 But, the standard is wrong. In particular, this code is
2891 legal C++:
2892
2893 int *ip;
2894 int **ipp = &ip;
2895 const int* const* cipp = ipp;
2896
2897 And, it doesn't make sense for that to be legal unless you
2898 can dereference IPP and CIPP. So, we ignore cv-qualifiers on
2899 the pointed-to types. This issue has been reported to the
2900 C++ committee. */
2901 t1 = build_type_no_quals (t);
2902 if (t1 != t)
2903 return get_alias_set (t1);
2904 }
2905
2906 /* Handle the case of multiple type nodes referring to "the same" type,
2907 which occurs with IMA. These share an alias set. FIXME: Currently only
2908 C90 is handled. (In C99 type compatibility is not transitive, which
2909 complicates things mightily. The alias set splay trees can theoretically
2910 represent this, but insertion is tricky when you consider all the
2911 different orders things might arrive in.) */
2912
2913 if (c_language != clk_c || flag_isoc99)
2914 return -1;
2915
2916 /* Save time if there's only one input file. */
2917 if (num_in_fnames == 1)
2918 return -1;
2919
2920 /* Pointers need special handling if they point to any type that
2921 needs special handling (below). */
2922 if (TREE_CODE (t) == POINTER_TYPE)
2923 {
2924 tree t2;
2925 /* Find bottom type under any nested POINTERs. */
2926 for (t2 = TREE_TYPE (t);
2927 TREE_CODE (t2) == POINTER_TYPE;
2928 t2 = TREE_TYPE (t2))
2929 ;
2930 if (TREE_CODE (t2) != RECORD_TYPE
2931 && TREE_CODE (t2) != ENUMERAL_TYPE
2932 && TREE_CODE (t2) != QUAL_UNION_TYPE
2933 && TREE_CODE (t2) != UNION_TYPE)
2934 return -1;
2935 if (TYPE_SIZE (t2) == 0)
2936 return -1;
2937 }
2938 /* These are the only cases that need special handling. */
2939 if (TREE_CODE (t) != RECORD_TYPE
2940 && TREE_CODE (t) != ENUMERAL_TYPE
2941 && TREE_CODE (t) != QUAL_UNION_TYPE
2942 && TREE_CODE (t) != UNION_TYPE
2943 && TREE_CODE (t) != POINTER_TYPE)
2944 return -1;
2945 /* Undefined? */
2946 if (TYPE_SIZE (t) == 0)
2947 return -1;
2948
2949 /* Look up t in hash table. Only one of the compatible types within each
2950 alias set is recorded in the table. */
2951 if (!type_hash_table)
2952 type_hash_table = htab_create_ggc (1021, c_type_hash,
2953 (htab_eq) lang_hooks.types_compatible_p,
2954 NULL);
2955 slot = htab_find_slot (type_hash_table, t, INSERT);
2956 if (*slot != NULL)
2957 {
2958 TYPE_ALIAS_SET (t) = TYPE_ALIAS_SET ((tree)*slot);
2959 return TYPE_ALIAS_SET ((tree)*slot);
2960 }
2961 else
2962 /* Our caller will assign and record (in t) a new alias set; all we need
2963 to do is remember t in the hash table. */
2964 *slot = t;
2965
2966 return -1;
2967}
2968
2969/* Compute the value of 'sizeof (TYPE)' or '__alignof__ (TYPE)', where the
2970 second parameter indicates which OPERATOR is being applied. The COMPLAIN
2971 flag controls whether we should diagnose possibly ill-formed
2972 constructs or not. */
2973
2974tree
2975c_sizeof_or_alignof_type (tree type, bool is_sizeof, int complain)
2976{
2977 const char *op_name;
2978 tree value = NULL;
2979 enum tree_code type_code = TREE_CODE (type);
2980
2981 op_name = is_sizeof ? "sizeof" : "__alignof__";
2982
2983 if (type_code == FUNCTION_TYPE)
2984 {
2985 if (is_sizeof)
2986 {
2987 if (complain && (pedantic || warn_pointer_arith))
2988 pedwarn ("invalid application of %<sizeof%> to a function type");
2989 value = size_one_node;
2990 }
2991 else
2992 value = size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
2993 }
2994 else if (type_code == VOID_TYPE || type_code == ERROR_MARK)
2995 {
2996 if (type_code == VOID_TYPE
2997 && complain && (pedantic || warn_pointer_arith))
2998 pedwarn ("invalid application of %qs to a void type", op_name);
2999 value = size_one_node;
3000 }
3001 else if (!COMPLETE_TYPE_P (type))
3002 {
3003 if (complain)
3004 error ("invalid application of %qs to incomplete type %qT ",
3005 op_name, type);
3006 value = size_zero_node;
3007 }
3008 else
3009 {
3010 if (is_sizeof)
3011 /* Convert in case a char is more than one unit. */
3012 value = size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
3013 size_int (TYPE_PRECISION (char_type_node)
3014 / BITS_PER_UNIT));
3015 else
3016 value = size_int (TYPE_ALIGN_UNIT (type));
3017 }
3018
3019 /* VALUE will have an integer type with TYPE_IS_SIZETYPE set.
3020 TYPE_IS_SIZETYPE means that certain things (like overflow) will
3021 never happen. However, this node should really have type
3022 `size_t', which is just a typedef for an ordinary integer type. */
3023 value = fold_convert (size_type_node, value);
3024 gcc_assert (!TYPE_IS_SIZETYPE (TREE_TYPE (value)));
3025
3026 return value;
3027}
3028
3029/* Implement the __alignof keyword: Return the minimum required
3030 alignment of EXPR, measured in bytes. For VAR_DECLs,
3031 FUNCTION_DECLs and FIELD_DECLs return DECL_ALIGN (which can be set
3032 from an "aligned" __attribute__ specification). */
3033
3034tree
3035c_alignof_expr (tree expr)
3036{
3037 tree t;
3038
3039 if (VAR_OR_FUNCTION_DECL_P (expr))
3040 t = size_int (DECL_ALIGN_UNIT (expr));
3041
3042 else if (TREE_CODE (expr) == COMPONENT_REF
3043 && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
3044 {
3045 error ("%<__alignof%> applied to a bit-field");
3046 t = size_one_node;
3047 }
3048 else if (TREE_CODE (expr) == COMPONENT_REF
3049 && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
3050 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (expr, 1)));
3051
3052 else if (TREE_CODE (expr) == INDIRECT_REF)
3053 {
3054 tree t = TREE_OPERAND (expr, 0);
3055 tree best = t;
3056 int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
3057
3058 while ((TREE_CODE (t) == NOP_EXPR || TREE_CODE (t) == CONVERT_EXPR)
3059 && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
3060 {
3061 int thisalign;
3062
3063 t = TREE_OPERAND (t, 0);
3064 thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
3065 if (thisalign > bestalign)
3066 best = t, bestalign = thisalign;
3067 }
3068 return c_alignof (TREE_TYPE (TREE_TYPE (best)));
3069 }
3070 else
3071 return c_alignof (TREE_TYPE (expr));
3072
3073 return fold_convert (size_type_node, t);
3074}
3075
3076/* Handle C and C++ default attributes. */
3077
3078enum built_in_attribute
3079{
3080#define DEF_ATTR_NULL_TREE(ENUM) ENUM,
3081#define DEF_ATTR_INT(ENUM, VALUE) ENUM,
3082#define DEF_ATTR_IDENT(ENUM, STRING) ENUM,
3083#define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM,
3084#include "builtin-attrs.def"
3085#undef DEF_ATTR_NULL_TREE
3086#undef DEF_ATTR_INT
3087#undef DEF_ATTR_IDENT
3088#undef DEF_ATTR_TREE_LIST
3089 ATTR_LAST
3090};
3091
3092static GTY(()) tree built_in_attributes[(int) ATTR_LAST];
3093
3094static void c_init_attributes (void);
3095
3096enum c_builtin_type
3097{
3098#define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME,
3099#define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME,
3100#define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME,
3101#define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME,
3102#define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
3103#define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
3104#define DEF_FUNCTION_TYPE_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) NAME,
3105#define DEF_FUNCTION_TYPE_6(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6) NAME,
3106#define DEF_FUNCTION_TYPE_7(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7) NAME,
3107#define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME,
3108#define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME,
3109#define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME,
3110#define DEF_FUNCTION_TYPE_VAR_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
3111#define DEF_FUNCTION_TYPE_VAR_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
3112#define DEF_FUNCTION_TYPE_VAR_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG6) \
3113 NAME,
3114#define DEF_POINTER_TYPE(NAME, TYPE) NAME,
3115#include "builtin-types.def"
3116#undef DEF_PRIMITIVE_TYPE
3117#undef DEF_FUNCTION_TYPE_0
3118#undef DEF_FUNCTION_TYPE_1
3119#undef DEF_FUNCTION_TYPE_2
3120#undef DEF_FUNCTION_TYPE_3
3121#undef DEF_FUNCTION_TYPE_4
3122#undef DEF_FUNCTION_TYPE_5
3123#undef DEF_FUNCTION_TYPE_6
3124#undef DEF_FUNCTION_TYPE_7
3125#undef DEF_FUNCTION_TYPE_VAR_0
3126#undef DEF_FUNCTION_TYPE_VAR_1
3127#undef DEF_FUNCTION_TYPE_VAR_2
3128#undef DEF_FUNCTION_TYPE_VAR_3
3129#undef DEF_FUNCTION_TYPE_VAR_4
3130#undef DEF_FUNCTION_TYPE_VAR_5
3131#undef DEF_POINTER_TYPE
3132 BT_LAST
3133};
3134
3135typedef enum c_builtin_type builtin_type;
3136
3137/* A temporary array for c_common_nodes_and_builtins. Used in
3138 communication with def_fn_type. */
3139static tree builtin_types[(int) BT_LAST + 1];
3140
3141/* A helper function for c_common_nodes_and_builtins. Build function type
3142 for DEF with return type RET and N arguments. If VAR is true, then the
3143 function should be variadic after those N arguments.
3144
3145 Takes special care not to ICE if any of the types involved are
3146 error_mark_node, which indicates that said type is not in fact available
3147 (see builtin_type_for_size). In which case the function type as a whole
3148 should be error_mark_node. */
3149
3150static void
3151def_fn_type (builtin_type def, builtin_type ret, bool var, int n, ...)
3152{
3153 tree args = NULL, t;
3154 va_list list;
3155 int i;
3156
3157 va_start (list, n);
3158 for (i = 0; i < n; ++i)
3159 {
3160 builtin_type a = va_arg (list, builtin_type);
3161 t = builtin_types[a];
3162 if (t == error_mark_node)
3163 goto egress;
3164 args = tree_cons (NULL_TREE, t, args);
3165 }
3166 va_end (list);
3167
3168 args = nreverse (args);
3169 if (!var)
3170 args = chainon (args, void_list_node);
3171
3172 t = builtin_types[ret];
3173 if (t == error_mark_node)
3174 goto egress;
3175 t = build_function_type (t, args);
3176
3177 egress:
3178 builtin_types[def] = t;
3179}
3180
3181/* Build builtin functions common to both C and C++ language
3182 frontends. */
3183
3184static void
3185c_define_builtins (tree va_list_ref_type_node, tree va_list_arg_type_node)
3186{
3187#define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \
3188 builtin_types[ENUM] = VALUE;
3189#define DEF_FUNCTION_TYPE_0(ENUM, RETURN) \
3190 def_fn_type (ENUM, RETURN, 0, 0);
3191#define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1) \
3192 def_fn_type (ENUM, RETURN, 0, 1, ARG1);
3193#define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2) \
3194 def_fn_type (ENUM, RETURN, 0, 2, ARG1, ARG2);
3195#define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
3196 def_fn_type (ENUM, RETURN, 0, 3, ARG1, ARG2, ARG3);
3197#define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
3198 def_fn_type (ENUM, RETURN, 0, 4, ARG1, ARG2, ARG3, ARG4);
3199#define DEF_FUNCTION_TYPE_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
3200 def_fn_type (ENUM, RETURN, 0, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
3201#define DEF_FUNCTION_TYPE_6(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3202 ARG6) \
3203 def_fn_type (ENUM, RETURN, 0, 6, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6);
3204#define DEF_FUNCTION_TYPE_7(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3205 ARG6, ARG7) \
3206 def_fn_type (ENUM, RETURN, 0, 7, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7);
3207#define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN) \
3208 def_fn_type (ENUM, RETURN, 1, 0);
3209#define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1) \
3210 def_fn_type (ENUM, RETURN, 1, 1, ARG1);
3211#define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2) \
3212 def_fn_type (ENUM, RETURN, 1, 2, ARG1, ARG2);
3213#define DEF_FUNCTION_TYPE_VAR_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
3214 def_fn_type (ENUM, RETURN, 1, 3, ARG1, ARG2, ARG3);
3215#define DEF_FUNCTION_TYPE_VAR_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
3216 def_fn_type (ENUM, RETURN, 1, 4, ARG1, ARG2, ARG3, ARG4);
3217#define DEF_FUNCTION_TYPE_VAR_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
3218 def_fn_type (ENUM, RETURN, 1, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
3219#define DEF_POINTER_TYPE(ENUM, TYPE) \
3220 builtin_types[(int) ENUM] = build_pointer_type (builtin_types[(int) TYPE]);
3221
3222#include "builtin-types.def"
3223
3224#undef DEF_PRIMITIVE_TYPE
3225#undef DEF_FUNCTION_TYPE_1
3226#undef DEF_FUNCTION_TYPE_2
3227#undef DEF_FUNCTION_TYPE_3
3228#undef DEF_FUNCTION_TYPE_4
3229#undef DEF_FUNCTION_TYPE_5
3230#undef DEF_FUNCTION_TYPE_6
3231#undef DEF_FUNCTION_TYPE_VAR_0
3232#undef DEF_FUNCTION_TYPE_VAR_1
3233#undef DEF_FUNCTION_TYPE_VAR_2
3234#undef DEF_FUNCTION_TYPE_VAR_3
3235#undef DEF_FUNCTION_TYPE_VAR_4
3236#undef DEF_FUNCTION_TYPE_VAR_5
3237#undef DEF_POINTER_TYPE
3238 builtin_types[(int) BT_LAST] = NULL_TREE;
3239
3240 c_init_attributes ();
3241
3242#define DEF_BUILTIN(ENUM, NAME, CLASS, TYPE, LIBTYPE, BOTH_P, FALLBACK_P, \
3243 NONANSI_P, ATTRS, IMPLICIT, COND) \
3244 if (NAME && COND) \
3245 def_builtin_1 (ENUM, NAME, CLASS, \
3246 builtin_types[(int) TYPE], \
3247 builtin_types[(int) LIBTYPE], \
3248 BOTH_P, FALLBACK_P, NONANSI_P, \
3249 built_in_attributes[(int) ATTRS], IMPLICIT);
3250#include "builtins.def"
3251#undef DEF_BUILTIN
3252
3253 build_common_builtin_nodes ();
3254
3255 targetm.init_builtins ();
3256 if (flag_mudflap)
3257 mudflap_init ();
3258}
3259
3260/* Build tree nodes and builtin functions common to both C and C++ language
3261 frontends. */
3262
3263void
3264c_common_nodes_and_builtins (void)
3265{
3266 int wchar_type_size;
3267 tree array_domain_type;
3268 tree va_list_ref_type_node;
3269 tree va_list_arg_type_node;
3270
3271 /* Define `int' and `char' first so that dbx will output them first. */
3272 record_builtin_type (RID_INT, NULL, integer_type_node);
3273 record_builtin_type (RID_CHAR, "char", char_type_node);
3274
3275 /* `signed' is the same as `int'. FIXME: the declarations of "signed",
3276 "unsigned long", "long long unsigned" and "unsigned short" were in C++
3277 but not C. Are the conditionals here needed? */
3278 if (c_dialect_cxx ())
3279 record_builtin_type (RID_SIGNED, NULL, integer_type_node);
3280 record_builtin_type (RID_LONG, "long int", long_integer_type_node);
3281 record_builtin_type (RID_UNSIGNED, "unsigned int", unsigned_type_node);
3282 record_builtin_type (RID_MAX, "long unsigned int",
3283 long_unsigned_type_node);
3284 if (c_dialect_cxx ())
3285 record_builtin_type (RID_MAX, "unsigned long", long_unsigned_type_node);
3286 record_builtin_type (RID_MAX, "long long int",
3287 long_long_integer_type_node);
3288 record_builtin_type (RID_MAX, "long long unsigned int",
3289 long_long_unsigned_type_node);
3290 if (c_dialect_cxx ())
3291 record_builtin_type (RID_MAX, "long long unsigned",
3292 long_long_unsigned_type_node);
3293 record_builtin_type (RID_SHORT, "short int", short_integer_type_node);
3294 record_builtin_type (RID_MAX, "short unsigned int",
3295 short_unsigned_type_node);
3296 if (c_dialect_cxx ())
3297 record_builtin_type (RID_MAX, "unsigned short",
3298 short_unsigned_type_node);
3299
3300 /* Define both `signed char' and `unsigned char'. */
3301 record_builtin_type (RID_MAX, "signed char", signed_char_type_node);
3302 record_builtin_type (RID_MAX, "unsigned char", unsigned_char_type_node);
3303
3304 /* These are types that c_common_type_for_size and
3305 c_common_type_for_mode use. */
3306 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3307 intQI_type_node));
3308 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3309 intHI_type_node));
3310 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3311 intSI_type_node));
3312 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3313 intDI_type_node));
3314#if HOST_BITS_PER_WIDE_INT >= 64
3315 if (targetm.scalar_mode_supported_p (TImode))
3316 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL,
3317 get_identifier ("__int128_t"),
3318 intTI_type_node));
3319#endif
3320 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3321 unsigned_intQI_type_node));
3322 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3323 unsigned_intHI_type_node));
3324 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3325 unsigned_intSI_type_node));
3326 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3327 unsigned_intDI_type_node));
3328#if HOST_BITS_PER_WIDE_INT >= 64
3329 if (targetm.scalar_mode_supported_p (TImode))
3330 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL,
3331 get_identifier ("__uint128_t"),
3332 unsigned_intTI_type_node));
3333#endif
3334
3335 /* Create the widest literal types. */
3336 widest_integer_literal_type_node
3337 = make_signed_type (HOST_BITS_PER_WIDE_INT * 2);
3338 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3339 widest_integer_literal_type_node));
3340
3341 widest_unsigned_literal_type_node
3342 = make_unsigned_type (HOST_BITS_PER_WIDE_INT * 2);
3343 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL, NULL_TREE,
3344 widest_unsigned_literal_type_node));
3345
3346 /* `unsigned long' is the standard type for sizeof.
3347 Note that stddef.h uses `unsigned long',
3348 and this must agree, even if long and int are the same size. */
3349 size_type_node =
3350 TREE_TYPE (identifier_global_value (get_identifier (SIZE_TYPE)));
3351 signed_size_type_node = c_common_signed_type (size_type_node);
3352 set_sizetype (size_type_node);
3353
3354 pid_type_node =
3355 TREE_TYPE (identifier_global_value (get_identifier (PID_TYPE)));
3356
3357 build_common_tree_nodes_2 (flag_short_double);
3358
3359 record_builtin_type (RID_FLOAT, NULL, float_type_node);
3360 record_builtin_type (RID_DOUBLE, NULL, double_type_node);
3361 record_builtin_type (RID_MAX, "long double", long_double_type_node);
3362
3363 /* Only supported decimal floating point extension if the target
3364 actually supports underlying modes. */
3365 if (targetm.scalar_mode_supported_p (SDmode)
3366 && targetm.scalar_mode_supported_p (DDmode)
3367 && targetm.scalar_mode_supported_p (TDmode))
3368 {
3369 record_builtin_type (RID_DFLOAT32, NULL, dfloat32_type_node);
3370 record_builtin_type (RID_DFLOAT64, NULL, dfloat64_type_node);
3371 record_builtin_type (RID_DFLOAT128, NULL, dfloat128_type_node);
3372 }
3373
3374 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL,
3375 get_identifier ("complex int"),
3376 complex_integer_type_node));
3377 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL,
3378 get_identifier ("complex float"),
3379 complex_float_type_node));
3380 lang_hooks.decls.pushdecl (build_decl (TYPE_DECL,
3381 get_identifier ("complex double"),
3382 complex_double_type_node));
3383 lang_hooks.decls.pushdecl
3384 (build_decl (TYPE_DECL, get_identifier ("complex long double"),
3385 complex_long_double_type_node));
3386
3387 if (c_dialect_cxx ())
3388 /* For C++, make fileptr_type_node a distinct void * type until
3389 FILE type is defined. */
3390 fileptr_type_node = build_variant_type_copy (ptr_type_node);
3391
3392 record_builtin_type (RID_VOID, NULL, void_type_node);
3393
3394 /* This node must not be shared. */
3395 void_zero_node = make_node (INTEGER_CST);
3396 TREE_TYPE (void_zero_node) = void_type_node;
3397
3398 void_list_node = build_void_list_node ();
3399
3400 /* Make a type to be the domain of a few array types
3401 whose domains don't really matter.
3402 200 is small enough that it always fits in size_t
3403 and large enough that it can hold most function names for the
3404 initializations of __FUNCTION__ and __PRETTY_FUNCTION__. */
3405 array_domain_type = build_index_type (size_int (200));
3406
3407 /* Make a type for arrays of characters.
3408 With luck nothing will ever really depend on the length of this
3409 array type. */
3410 char_array_type_node
3411 = build_array_type (char_type_node, array_domain_type);
3412
3413 /* Likewise for arrays of ints. */
3414 int_array_type_node
3415 = build_array_type (integer_type_node, array_domain_type);
3416
3417 string_type_node = build_pointer_type (char_type_node);
3418 const_string_type_node
3419 = build_pointer_type (build_qualified_type
3420 (char_type_node, TYPE_QUAL_CONST));
3421
3422 /* This is special for C++ so functions can be overloaded. */
3423 wchar_type_node = get_identifier (MODIFIED_WCHAR_TYPE);
3424 wchar_type_node = TREE_TYPE (identifier_global_value (wchar_type_node));
3425 wchar_type_size = TYPE_PRECISION (wchar_type_node);
3426 if (c_dialect_cxx ())
3427 {
3428 if (TYPE_UNSIGNED (wchar_type_node))
3429 wchar_type_node = make_unsigned_type (wchar_type_size);
3430 else
3431 wchar_type_node = make_signed_type (wchar_type_size);
3432 record_builtin_type (RID_WCHAR, "wchar_t", wchar_type_node);
3433 }
3434 else
3435 {
3436 signed_wchar_type_node = c_common_signed_type (wchar_type_node);
3437 unsigned_wchar_type_node = c_common_unsigned_type (wchar_type_node);
3438 }
3439
3440 /* This is for wide string constants. */
3441 wchar_array_type_node
3442 = build_array_type (wchar_type_node, array_domain_type);
3443
3444 wint_type_node =
3445 TREE_TYPE (identifier_global_value (get_identifier (WINT_TYPE)));
3446
3447 intmax_type_node =
3448 TREE_TYPE (identifier_global_value (get_identifier (INTMAX_TYPE)));
3449 uintmax_type_node =
3450 TREE_TYPE (identifier_global_value (get_identifier (UINTMAX_TYPE)));
3451
3452 default_function_type = build_function_type (integer_type_node, NULL_TREE);
3453 ptrdiff_type_node
3454 = TREE_TYPE (identifier_global_value (get_identifier (PTRDIFF_TYPE)));
3455 unsigned_ptrdiff_type_node = c_common_unsigned_type (ptrdiff_type_node);
3456
3457 lang_hooks.decls.pushdecl
3458 (build_decl (TYPE_DECL, get_identifier ("__builtin_va_list"),
3459 va_list_type_node));
3460
3461 if (TREE_CODE (va_list_type_node) == ARRAY_TYPE)
3462 {
3463 va_list_arg_type_node = va_list_ref_type_node =
3464 build_pointer_type (TREE_TYPE (va_list_type_node));
3465 }
3466 else
3467 {
3468 va_list_arg_type_node = va_list_type_node;
3469 va_list_ref_type_node = build_reference_type (va_list_type_node);
3470 }
3471
3472 if (!flag_preprocess_only)
3473 c_define_builtins (va_list_ref_type_node, va_list_arg_type_node);
3474
3475 main_identifier_node = get_identifier ("main");
3476
3477 /* Create the built-in __null node. It is important that this is
3478 not shared. */
3479 null_node = make_node (INTEGER_CST);
3480 TREE_TYPE (null_node) = c_common_type_for_size (POINTER_SIZE, 0);
3481
3482 /* Since builtin_types isn't gc'ed, don't export these nodes. */
3483 memset (builtin_types, 0, sizeof (builtin_types));
3484}
3485
3486/* Look up the function in built_in_decls that corresponds to DECL
3487 and set ASMSPEC as its user assembler name. DECL must be a
3488 function decl that declares a builtin. */
3489
3490void
3491set_builtin_user_assembler_name (tree decl, const char *asmspec)
3492{
3493 tree builtin;
3494 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
3495 && DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
3496 && asmspec != 0);
3497
3498 builtin = built_in_decls [DECL_FUNCTION_CODE (decl)];
3499 set_user_assembler_name (builtin, asmspec);
3500 if (DECL_FUNCTION_CODE (decl) == BUILT_IN_MEMCPY)
3501 init_block_move_fn (asmspec);
3502 else if (DECL_FUNCTION_CODE (decl) == BUILT_IN_MEMSET)
3503 init_block_clear_fn (asmspec);
3504}
3505
3506/* The number of named compound-literals generated thus far. */
3507static GTY(()) int compound_literal_number;
3508
3509/* Set DECL_NAME for DECL, a VAR_DECL for a compound-literal. */
3510
3511void
3512set_compound_literal_name (tree decl)
3513{
3514 char *name;
3515 ASM_FORMAT_PRIVATE_NAME (name, "__compound_literal",
3516 compound_literal_number);
3517 compound_literal_number++;
3518 DECL_NAME (decl) = get_identifier (name);
3519}
3520
3521tree
3522build_va_arg (tree expr, tree type)
3523{
3524 return build1 (VA_ARG_EXPR, type, expr);
3525}
3526
3527
3528/* Linked list of disabled built-in functions. */
3529
3530typedef struct disabled_builtin
3531{
3532 const char *name;
3533 struct disabled_builtin *next;
3534} disabled_builtin;
3535static disabled_builtin *disabled_builtins = NULL;
3536
3537static bool builtin_function_disabled_p (const char *);
3538
3539/* Disable a built-in function specified by -fno-builtin-NAME. If NAME
3540 begins with "__builtin_", give an error. */
3541
3542void
3543disable_builtin_function (const char *name)
3544{
3545 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
3546 error ("cannot disable built-in function %qs", name);
3547 else
3548 {
3549 disabled_builtin *new_disabled_builtin = XNEW (disabled_builtin);
3550 new_disabled_builtin->name = name;
3551 new_disabled_builtin->next = disabled_builtins;
3552 disabled_builtins = new_disabled_builtin;
3553 }
3554}
3555
3556
3557/* Return true if the built-in function NAME has been disabled, false
3558 otherwise. */
3559
3560static bool
3561builtin_function_disabled_p (const char *name)
3562{
3563 disabled_builtin *p;
3564 for (p = disabled_builtins; p != NULL; p = p->next)
3565 {
3566 if (strcmp (name, p->name) == 0)
3567 return true;
3568 }
3569 return false;
3570}
3571
3572
3573/* Worker for DEF_BUILTIN.
3574 Possibly define a builtin function with one or two names.
3575 Does not declare a non-__builtin_ function if flag_no_builtin, or if
3576 nonansi_p and flag_no_nonansi_builtin. */
3577
3578static void
3579def_builtin_1 (enum built_in_function fncode,
3580 const char *name,
3581 enum built_in_class fnclass,
3582 tree fntype, tree libtype,
3583 bool both_p, bool fallback_p, bool nonansi_p,
3584 tree fnattrs, bool implicit_p)
3585{
3586 tree decl;
3587 const char *libname;
3588
3589 if (fntype == error_mark_node)
3590 return;
3591
3592 gcc_assert ((!both_p && !fallback_p)
3593 || !strncmp (name, "__builtin_",
3594 strlen ("__builtin_")));
3595
3596 libname = name + strlen ("__builtin_");
3597 decl = lang_hooks.builtin_function (name, fntype, fncode, fnclass,
3598 (fallback_p ? libname : NULL),
3599 fnattrs);
3600 if (both_p
3601 && !flag_no_builtin && !builtin_function_disabled_p (libname)
3602 && !(nonansi_p && flag_no_nonansi_builtin))
3603 lang_hooks.builtin_function (libname, libtype, fncode, fnclass,
3604 NULL, fnattrs);
3605
3606 built_in_decls[(int) fncode] = decl;
3607 if (implicit_p)
3608 implicit_built_in_decls[(int) fncode] = decl;
3609}
3610
3611/* Nonzero if the type T promotes to int. This is (nearly) the
3612 integral promotions defined in ISO C99 6.3.1.1/2. */
3613
3614bool
3615c_promoting_integer_type_p (tree t)
3616{
3617 switch (TREE_CODE (t))
3618 {
3619 case INTEGER_TYPE:
3620 return (TYPE_MAIN_VARIANT (t) == char_type_node
3621 || TYPE_MAIN_VARIANT (t) == signed_char_type_node
3622 || TYPE_MAIN_VARIANT (t) == unsigned_char_type_node
3623 || TYPE_MAIN_VARIANT (t) == short_integer_type_node
3624 || TYPE_MAIN_VARIANT (t) == short_unsigned_type_node
3625 || TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node));
3626
3627 case ENUMERAL_TYPE:
3628 /* ??? Technically all enumerations not larger than an int
3629 promote to an int. But this is used along code paths
3630 that only want to notice a size change. */
3631 return TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node);
3632
3633 case BOOLEAN_TYPE:
3634 return 1;
3635
3636 default:
3637 return 0;
3638 }
3639}
3640
3641/* Return 1 if PARMS specifies a fixed number of parameters
3642 and none of their types is affected by default promotions. */
3643
3644int
3645self_promoting_args_p (tree parms)
3646{
3647 tree t;
3648 for (t = parms; t; t = TREE_CHAIN (t))
3649 {
3650 tree type = TREE_VALUE (t);
3651
3652 if (type == error_mark_node)
3653 continue;
3654
3655 if (TREE_CHAIN (t) == 0 && type != void_type_node)
3656 return 0;
3657
3658 if (type == 0)
3659 return 0;
3660
3661 if (TYPE_MAIN_VARIANT (type) == float_type_node)
3662 return 0;
3663
3664 if (c_promoting_integer_type_p (type))
3665 return 0;
3666 }
3667 return 1;
3668}
3669
3670/* Recursively examines the array elements of TYPE, until a non-array
3671 element type is found. */
3672
3673tree
3674strip_array_types (tree type)
3675{
3676 while (TREE_CODE (type) == ARRAY_TYPE)
3677 type = TREE_TYPE (type);
3678
3679 return type;
3680}
3681
3682/* Recursively remove any '*' or '&' operator from TYPE. */
3683tree
3684strip_pointer_operator (tree t)
3685{
3686 while (POINTER_TYPE_P (t))
3687 t = TREE_TYPE (t);
3688 return t;
3689}
3690
3691/* Used to compare case labels. K1 and K2 are actually tree nodes
3692 representing case labels, or NULL_TREE for a `default' label.
3693 Returns -1 if K1 is ordered before K2, -1 if K1 is ordered after
3694 K2, and 0 if K1 and K2 are equal. */
3695
3696int
3697case_compare (splay_tree_key k1, splay_tree_key k2)
3698{
3699 /* Consider a NULL key (such as arises with a `default' label) to be
3700 smaller than anything else. */
3701 if (!k1)
3702 return k2 ? -1 : 0;
3703 else if (!k2)
3704 return k1 ? 1 : 0;
3705
3706 return tree_int_cst_compare ((tree) k1, (tree) k2);
3707}
3708
3709/* Process a case label for the range LOW_VALUE ... HIGH_VALUE. If
3710 LOW_VALUE and HIGH_VALUE are both NULL_TREE then this case label is
3711 actually a `default' label. If only HIGH_VALUE is NULL_TREE, then
3712 case label was declared using the usual C/C++ syntax, rather than
3713 the GNU case range extension. CASES is a tree containing all the
3714 case ranges processed so far; COND is the condition for the
3715 switch-statement itself. Returns the CASE_LABEL_EXPR created, or
3716 ERROR_MARK_NODE if no CASE_LABEL_EXPR is created. */
3717
3718tree
3719c_add_case_label (splay_tree cases, tree cond, tree orig_type,
3720 tree low_value, tree high_value)
3721{
3722 tree type;
3723 tree label;
3724 tree case_label;
3725 splay_tree_node node;
3726
3727 /* Create the LABEL_DECL itself. */
3728 label = create_artificial_label ();
3729
3730 /* If there was an error processing the switch condition, bail now
3731 before we get more confused. */
3732 if (!cond || cond == error_mark_node)
3733 goto error_out;
3734
3735 if ((low_value && TREE_TYPE (low_value)
3736 && POINTER_TYPE_P (TREE_TYPE (low_value)))
3737 || (high_value && TREE_TYPE (high_value)
3738 && POINTER_TYPE_P (TREE_TYPE (high_value))))
3739 {
3740 error ("pointers are not permitted as case values");
3741 goto error_out;
3742 }
3743
3744 /* Case ranges are a GNU extension. */
3745 if (high_value && pedantic)
3746 pedwarn ("range expressions in switch statements are non-standard");
3747
3748 type = TREE_TYPE (cond);
3749 if (low_value)
3750 {
3751 low_value = check_case_value (low_value);
3752 low_value = convert_and_check (type, low_value);
3753 if (low_value == error_mark_node)
3754 goto error_out;
3755 }
3756 if (high_value)
3757 {
3758 high_value = check_case_value (high_value);
3759 high_value = convert_and_check (type, high_value);
3760 if (high_value == error_mark_node)
3761 goto error_out;
3762 }
3763
3764 if (low_value && high_value)
3765 {
3766 /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
3767 really a case range, even though it was written that way.
3768 Remove the HIGH_VALUE to simplify later processing. */
3769 if (tree_int_cst_equal (low_value, high_value))
3770 high_value = NULL_TREE;
3771 else if (!tree_int_cst_lt (low_value, high_value))
3772 warning (0, "empty range specified");
3773 }
3774
3775 /* See if the case is in range of the type of the original testing
3776 expression. If both low_value and high_value are out of range,
3777 don't insert the case label and return NULL_TREE. */
3778 if (low_value
3779 && !check_case_bounds (type, orig_type,
3780 &low_value, high_value ? &high_value : NULL))
3781 return NULL_TREE;
3782
3783 /* Look up the LOW_VALUE in the table of case labels we already
3784 have. */
3785 node = splay_tree_lookup (cases, (splay_tree_key) low_value);
3786 /* If there was not an exact match, check for overlapping ranges.
3787 There's no need to do this if there's no LOW_VALUE or HIGH_VALUE;
3788 that's a `default' label and the only overlap is an exact match. */
3789 if (!node && (low_value || high_value))
3790 {
3791 splay_tree_node low_bound;
3792 splay_tree_node high_bound;
3793
3794 /* Even though there wasn't an exact match, there might be an
3795 overlap between this case range and another case range.
3796 Since we've (inductively) not allowed any overlapping case
3797 ranges, we simply need to find the greatest low case label
3798 that is smaller that LOW_VALUE, and the smallest low case
3799 label that is greater than LOW_VALUE. If there is an overlap
3800 it will occur in one of these two ranges. */
3801 low_bound = splay_tree_predecessor (cases,
3802 (splay_tree_key) low_value);
3803 high_bound = splay_tree_successor (cases,
3804 (splay_tree_key) low_value);
3805
3806 /* Check to see if the LOW_BOUND overlaps. It is smaller than
3807 the LOW_VALUE, so there is no need to check unless the
3808 LOW_BOUND is in fact itself a case range. */
3809 if (low_bound
3810 && CASE_HIGH ((tree) low_bound->value)
3811 && tree_int_cst_compare (CASE_HIGH ((tree) low_bound->value),
3812 low_value) >= 0)
3813 node = low_bound;
3814 /* Check to see if the HIGH_BOUND overlaps. The low end of that
3815 range is bigger than the low end of the current range, so we
3816 are only interested if the current range is a real range, and
3817 not an ordinary case label. */
3818 else if (high_bound
3819 && high_value
3820 && (tree_int_cst_compare ((tree) high_bound->key,
3821 high_value)
3822 <= 0))
3823 node = high_bound;
3824 }
3825 /* If there was an overlap, issue an error. */
3826 if (node)
3827 {
3828 tree duplicate = CASE_LABEL ((tree) node->value);
3829
3830 if (high_value)
3831 {
3832 error ("duplicate (or overlapping) case value");
3833 error ("%Jthis is the first entry overlapping that value", duplicate);
3834 }
3835 else if (low_value)
3836 {
3837 error ("duplicate case value") ;
3838 error ("%Jpreviously used here", duplicate);
3839 }
3840 else
3841 {
3842 error ("multiple default labels in one switch");
3843 error ("%Jthis is the first default label", duplicate);
3844 }
3845 goto error_out;
3846 }
3847
3848 /* Add a CASE_LABEL to the statement-tree. */
3849 case_label = add_stmt (build_case_label (low_value, high_value, label));
3850 /* Register this case label in the splay tree. */
3851 splay_tree_insert (cases,
3852 (splay_tree_key) low_value,
3853 (splay_tree_value) case_label);
3854
3855 return case_label;
3856
3857 error_out:
3858 /* Add a label so that the back-end doesn't think that the beginning of
3859 the switch is unreachable. Note that we do not add a case label, as
3860 that just leads to duplicates and thence to failure later on. */
3861 if (!cases->root)
3862 {
3863 tree t = create_artificial_label ();
3864 add_stmt (build_stmt (LABEL_EXPR, t));
3865 }
3866 return error_mark_node;
3867}
3868
3869/* Subroutines of c_do_switch_warnings, called via splay_tree_foreach.
3870 Used to verify that case values match up with enumerator values. */
3871
3872static void
3873match_case_to_enum_1 (tree key, tree type, tree label)
3874{
3875 char buf[2 + 2*HOST_BITS_PER_WIDE_INT/4 + 1];
3876
3877 /* ??? Not working too hard to print the double-word value.
3878 Should perhaps be done with %lwd in the diagnostic routines? */
3879 if (TREE_INT_CST_HIGH (key) == 0)
3880 snprintf (buf, sizeof (buf), HOST_WIDE_INT_PRINT_UNSIGNED,
3881 TREE_INT_CST_LOW (key));
3882 else if (!TYPE_UNSIGNED (type)
3883 && TREE_INT_CST_HIGH (key) == -1
3884 && TREE_INT_CST_LOW (key) != 0)
3885 snprintf (buf, sizeof (buf), "-" HOST_WIDE_INT_PRINT_UNSIGNED,
3886 -TREE_INT_CST_LOW (key));
3887 else
3888 snprintf (buf, sizeof (buf), HOST_WIDE_INT_PRINT_DOUBLE_HEX,
3889 TREE_INT_CST_HIGH (key), TREE_INT_CST_LOW (key));
3890
3891 if (TYPE_NAME (type) == 0)
3892 warning (0, "%Jcase value %qs not in enumerated type",
3893 CASE_LABEL (label), buf);
3894 else
3895 warning (0, "%Jcase value %qs not in enumerated type %qT",
3896 CASE_LABEL (label), buf, type);
3897}
3898
3899/* Subroutine of c_do_switch_warnings, called via splay_tree_foreach.
3900 Used to verify that case values match up with enumerator values. */
3901
3902static int
3903match_case_to_enum (splay_tree_node node, void *data)
3904{
3905 tree label = (tree) node->value;
3906 tree type = (tree) data;
3907
3908 /* Skip default case. */
3909 if (!CASE_LOW (label))
3910 return 0;
3911
3912 /* If CASE_LOW_SEEN is not set, that means CASE_LOW did not appear
3913 when we did our enum->case scan. Reset our scratch bit after. */
3914 if (!CASE_LOW_SEEN (label))
3915 match_case_to_enum_1 (CASE_LOW (label), type, label);
3916 else
3917 CASE_LOW_SEEN (label) = 0;
3918
3919 /* If CASE_HIGH is non-null, we have a range. If CASE_HIGH_SEEN is
3920 not set, that means that CASE_HIGH did not appear when we did our
3921 enum->case scan. Reset our scratch bit after. */
3922 if (CASE_HIGH (label))
3923 {
3924 if (!CASE_HIGH_SEEN (label))
3925 match_case_to_enum_1 (CASE_HIGH (label), type, label);
3926 else
3927 CASE_HIGH_SEEN (label) = 0;
3928 }
3929
3930 return 0;
3931}
3932
3933/* Handle -Wswitch*. Called from the front end after parsing the
3934 switch construct. */
3935/* ??? Should probably be somewhere generic, since other languages
3936 besides C and C++ would want this. At the moment, however, C/C++
3937 are the only tree-ssa languages that support enumerations at all,
3938 so the point is moot. */
3939
3940void
3941c_do_switch_warnings (splay_tree cases, location_t switch_location,
3942 tree type, tree cond)
3943{
3944 splay_tree_node default_node;
3945 splay_tree_node node;
3946 tree chain;
3947
3948 if (!warn_switch && !warn_switch_enum && !warn_switch_default)
3949 return;
3950
3951 default_node = splay_tree_lookup (cases, (splay_tree_key) NULL);
3952 if (!default_node)
3953 warning (OPT_Wswitch_default, "%Hswitch missing default case",
3954 &switch_location);
3955
3956 /* From here on, we only care about about enumerated types. */
3957 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
3958 return;
3959
3960 /* If the switch expression was an enumerated type, check that
3961 exactly all enumeration literals are covered by the cases.
3962 The check is made when -Wswitch was specified and there is no
3963 default case, or when -Wswitch-enum was specified. */
3964
3965 if (!warn_switch_enum
3966 && !(warn_switch && !default_node))
3967 return;
3968
3969 /* Clearing COND if it is not an integer constant simplifies
3970 the tests inside the loop below. */
3971 if (TREE_CODE (cond) != INTEGER_CST)
3972 cond = NULL_TREE;
3973
3974 /* The time complexity here is O(N*lg(N)) worst case, but for the
3975 common case of monotonically increasing enumerators, it is
3976 O(N), since the nature of the splay tree will keep the next
3977 element adjacent to the root at all times. */
3978
3979 for (chain = TYPE_VALUES (type); chain; chain = TREE_CHAIN (chain))
3980 {
3981 tree value = TREE_VALUE (chain);
3982 node = splay_tree_lookup (cases, (splay_tree_key) value);
3983 if (node)
3984 {
3985 /* Mark the CASE_LOW part of the case entry as seen. */
3986 tree label = (tree) node->value;
3987 CASE_LOW_SEEN (label) = 1;
3988 continue;
3989 }
3990
3991 /* Even though there wasn't an exact match, there might be a
3992 case range which includes the enumator's value. */
3993 node = splay_tree_predecessor (cases, (splay_tree_key) value);
3994 if (node && CASE_HIGH ((tree) node->value))
3995 {
3996 tree label = (tree) node->value;
3997 int cmp = tree_int_cst_compare (CASE_HIGH (label), value);
3998 if (cmp >= 0)
3999 {
4000 /* If we match the upper bound exactly, mark the CASE_HIGH
4001 part of the case entry as seen. */
4002 if (cmp == 0)
4003 CASE_HIGH_SEEN (label) = 1;
4004 continue;
4005 }
4006 }
4007
4008 /* We've now determined that this enumerated literal isn't
4009 handled by the case labels of the switch statement. */
4010
4011 /* If the switch expression is a constant, we only really care
4012 about whether that constant is handled by the switch. */
4013 if (cond && tree_int_cst_compare (cond, value))
4014 continue;
4015
4016 warning (0, "%Henumeration value %qE not handled in switch",
4017 &switch_location, TREE_PURPOSE (chain));
4018 }
4019
4020 /* Warn if there are case expressions that don't correspond to
4021 enumerators. This can occur since C and C++ don't enforce
4022 type-checking of assignments to enumeration variables.
4023
4024 The time complexity here is now always O(N) worst case, since
4025 we should have marked both the lower bound and upper bound of
4026 every disjoint case label, with CASE_LOW_SEEN and CASE_HIGH_SEEN
4027 above. This scan also resets those fields. */
4028 splay_tree_foreach (cases, match_case_to_enum, type);
4029}
4030
4031/* Finish an expression taking the address of LABEL (an
4032 IDENTIFIER_NODE). Returns an expression for the address. */
4033
4034tree
4035finish_label_address_expr (tree label)
4036{
4037 tree result;
4038
4039 if (pedantic)
4040 pedwarn ("taking the address of a label is non-standard");
4041
4042 if (label == error_mark_node)
4043 return error_mark_node;
4044
4045 label = lookup_label (label);
4046 if (label == NULL_TREE)
4047 result = null_pointer_node;
4048 else
4049 {
4050 TREE_USED (label) = 1;
4051 result = build1 (ADDR_EXPR, ptr_type_node, label);
4052 /* The current function in not necessarily uninlinable.
4053 Computed gotos are incompatible with inlining, but the value
4054 here could be used only in a diagnostic, for example. */
4055 }
4056
4057 return result;
4058}
4059
4060/* Hook used by expand_expr to expand language-specific tree codes. */
4061/* The only things that should go here are bits needed to expand
4062 constant initializers. Everything else should be handled by the
4063 gimplification routines. */
4064
4065rtx
4066c_expand_expr (tree exp, rtx target, enum machine_mode tmode,
4067 int modifier /* Actually enum_modifier. */,
4068 rtx *alt_rtl)
4069{
4070 switch (TREE_CODE (exp))
4071 {
4072 case COMPOUND_LITERAL_EXPR:
4073 {
4074 /* Initialize the anonymous variable declared in the compound
4075 literal, then return the variable. */
4076 tree decl = COMPOUND_LITERAL_EXPR_DECL (exp);
4077 emit_local_var (decl);
4078 return expand_expr_real (decl, target, tmode, modifier, alt_rtl);
4079 }
4080
4081 default:
4082 gcc_unreachable ();
4083 }
4084}
4085
4086/* Hook used by staticp to handle language-specific tree codes. */
4087
4088tree
4089c_staticp (tree exp)
4090{
4091 return (TREE_CODE (exp) == COMPOUND_LITERAL_EXPR
4092 && TREE_STATIC (COMPOUND_LITERAL_EXPR_DECL (exp))
4093 ? exp : NULL);
4094}
4095
4096
4097/* Given a boolean expression ARG, return a tree representing an increment
4098 or decrement (as indicated by CODE) of ARG. The front end must check for
4099 invalid cases (e.g., decrement in C++). */
4100tree
4101boolean_increment (enum tree_code code, tree arg)
4102{
4103 tree val;
4104 tree true_res = boolean_true_node;
4105
4106 arg = stabilize_reference (arg);
4107 switch (code)
4108 {
4109 case PREINCREMENT_EXPR:
4110 val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
4111 break;
4112 case POSTINCREMENT_EXPR:
4113 val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
4114 arg = save_expr (arg);
4115 val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
4116 val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
4117 break;
4118 case PREDECREMENT_EXPR:
4119 val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg,
4120 invert_truthvalue (arg));
4121 break;
4122 case POSTDECREMENT_EXPR:
4123 val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg,
4124 invert_truthvalue (arg));
4125 arg = save_expr (arg);
4126 val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
4127 val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
4128 break;
4129 default:
4130 gcc_unreachable ();
4131 }
4132 TREE_SIDE_EFFECTS (val) = 1;
4133 return val;
4134}
4135
4136/* Built-in macros for stddef.h, that require macros defined in this
4137 file. */
4138void
4139c_stddef_cpp_builtins(void)
4140{
4141 builtin_define_with_value ("__SIZE_TYPE__", SIZE_TYPE, 0);
4142 builtin_define_with_value ("__PTRDIFF_TYPE__", PTRDIFF_TYPE, 0);
4143 builtin_define_with_value ("__WCHAR_TYPE__", MODIFIED_WCHAR_TYPE, 0);
4144 builtin_define_with_value ("__WINT_TYPE__", WINT_TYPE, 0);
4145 builtin_define_with_value ("__INTMAX_TYPE__", INTMAX_TYPE, 0);
4146 builtin_define_with_value ("__UINTMAX_TYPE__", UINTMAX_TYPE, 0);
4147}
4148
4149static void
4150c_init_attributes (void)
4151{
4152 /* Fill in the built_in_attributes array. */
4153#define DEF_ATTR_NULL_TREE(ENUM) \
4154 built_in_attributes[(int) ENUM] = NULL_TREE;
4155#define DEF_ATTR_INT(ENUM, VALUE) \
4156 built_in_attributes[(int) ENUM] = build_int_cst (NULL_TREE, VALUE);
4157#define DEF_ATTR_IDENT(ENUM, STRING) \
4158 built_in_attributes[(int) ENUM] = get_identifier (STRING);
4159#define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) \
4160 built_in_attributes[(int) ENUM] \
4161 = tree_cons (built_in_attributes[(int) PURPOSE], \
4162 built_in_attributes[(int) VALUE], \
4163 built_in_attributes[(int) CHAIN]);
4164#include "builtin-attrs.def"
4165#undef DEF_ATTR_NULL_TREE
4166#undef DEF_ATTR_INT
4167#undef DEF_ATTR_IDENT
4168#undef DEF_ATTR_TREE_LIST
4169}
4170
4171/* Attribute handlers common to C front ends. */
4172
4173/* Handle a "packed" attribute; arguments as in
4174 struct attribute_spec.handler. */
4175
4176static tree
4177handle_packed_attribute (tree *node, tree name, tree ARG_UNUSED (args),
4178 int flags, bool *no_add_attrs)
4179{
4180 if (TYPE_P (*node))
4181 {
4182 if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4183 *node = build_variant_type_copy (*node);
4184 TYPE_PACKED (*node) = 1;
4185 }
4186 else if (TREE_CODE (*node) == FIELD_DECL)
4187 {
4188 if (TYPE_ALIGN (TREE_TYPE (*node)) <= BITS_PER_UNIT)
4189 warning (OPT_Wattributes,
4190 "%qE attribute ignored for field of type %qT",
4191 name, TREE_TYPE (*node));
4192 else
4193 DECL_PACKED (*node) = 1;
4194 }
4195 /* We can't set DECL_PACKED for a VAR_DECL, because the bit is
4196 used for DECL_REGISTER. It wouldn't mean anything anyway.
4197 We can't set DECL_PACKED on the type of a TYPE_DECL, because
4198 that changes what the typedef is typing. */
4199 else
4200 {
4201 warning (OPT_Wattributes, "%qE attribute ignored", name);
4202 *no_add_attrs = true;
4203 }
4204
4205 return NULL_TREE;
4206}
4207
4208/* Handle a "nocommon" attribute; arguments as in
4209 struct attribute_spec.handler. */
4210
4211static tree
4212handle_nocommon_attribute (tree *node, tree name,
4213 tree ARG_UNUSED (args),
4214 int ARG_UNUSED (flags), bool *no_add_attrs)
4215{
4216 if (TREE_CODE (*node) == VAR_DECL)
4217 DECL_COMMON (*node) = 0;
4218 else
4219 {
4220 warning (OPT_Wattributes, "%qE attribute ignored", name);
4221 *no_add_attrs = true;
4222 }
4223
4224 return NULL_TREE;
4225}
4226
4227/* Handle a "common" attribute; arguments as in
4228 struct attribute_spec.handler. */
4229
4230static tree
4231handle_common_attribute (tree *node, tree name, tree ARG_UNUSED (args),
4232 int ARG_UNUSED (flags), bool *no_add_attrs)
4233{
4234 if (TREE_CODE (*node) == VAR_DECL)
4235 DECL_COMMON (*node) = 1;
4236 else
4237 {
4238 warning (OPT_Wattributes, "%qE attribute ignored", name);
4239 *no_add_attrs = true;
4240 }
4241
4242 return NULL_TREE;
4243}
4244
4245/* Handle a "noreturn" attribute; arguments as in
4246 struct attribute_spec.handler. */
4247
4248static tree
4249handle_noreturn_attribute (tree *node, tree name, tree ARG_UNUSED (args),
4250 int ARG_UNUSED (flags), bool *no_add_attrs)
4251{
4252 tree type = TREE_TYPE (*node);
4253
4254 /* See FIXME comment in c_common_attribute_table. */
4255 if (TREE_CODE (*node) == FUNCTION_DECL)
4256 TREE_THIS_VOLATILE (*node) = 1;
4257 else if (TREE_CODE (type) == POINTER_TYPE
4258 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4259 TREE_TYPE (*node)
4260 = build_pointer_type
4261 (build_type_variant (TREE_TYPE (type),
4262 TYPE_READONLY (TREE_TYPE (type)), 1));
4263 else
4264 {
4265 warning (OPT_Wattributes, "%qE attribute ignored", name);
4266 *no_add_attrs = true;
4267 }
4268
4269 return NULL_TREE;
4270}
4271
4272/* Handle a "noinline" attribute; arguments as in
4273 struct attribute_spec.handler. */
4274
4275static tree
4276handle_noinline_attribute (tree *node, tree name,
4277 tree ARG_UNUSED (args),
4278 int ARG_UNUSED (flags), bool *no_add_attrs)
4279{
4280 if (TREE_CODE (*node) == FUNCTION_DECL)
4281 DECL_UNINLINABLE (*node) = 1;
4282 else
4283 {
4284 warning (OPT_Wattributes, "%qE attribute ignored", name);
4285 *no_add_attrs = true;
4286 }
4287
4288 return NULL_TREE;
4289}
4290
4291/* Handle a "always_inline" attribute; arguments as in
4292 struct attribute_spec.handler. */
4293
4294static tree
4295handle_always_inline_attribute (tree *node, tree name,
4296 tree ARG_UNUSED (args),
4297 int ARG_UNUSED (flags),
4298 bool *no_add_attrs)
4299{
4300 if (TREE_CODE (*node) == FUNCTION_DECL)
4301 {
4302 /* Do nothing else, just set the attribute. We'll get at
4303 it later with lookup_attribute. */
4304 }
4305 else
4306 {
4307 warning (OPT_Wattributes, "%qE attribute ignored", name);
4308 *no_add_attrs = true;
4309 }
4310
4311 return NULL_TREE;
4312}
4313
4314/* Handle a "gnu_inline" attribute; arguments as in
4315 struct attribute_spec.handler. */
4316
4317static tree
4318handle_gnu_inline_attribute (tree *node, tree name,
4319 tree ARG_UNUSED (args),
4320 int ARG_UNUSED (flags),
4321 bool *no_add_attrs)
4322{
4323 if (TREE_CODE (*node) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (*node))
4324 {
4325 /* Do nothing else, just set the attribute. We'll get at
4326 it later with lookup_attribute. */
4327 }
4328 else
4329 {
4330 warning (OPT_Wattributes, "%qE attribute ignored", name);
4331 *no_add_attrs = true;
4332 }
4333
4334 return NULL_TREE;
4335}
4336
4337/* Handle a "flatten" attribute; arguments as in
4338 struct attribute_spec.handler. */
4339
4340static tree
4341handle_flatten_attribute (tree *node, tree name,
4342 tree args ATTRIBUTE_UNUSED,
4343 int flags ATTRIBUTE_UNUSED, bool *no_add_attrs)
4344{
4345 if (TREE_CODE (*node) == FUNCTION_DECL)
4346 /* Do nothing else, just set the attribute. We'll get at
4347 it later with lookup_attribute. */
4348 ;
4349 else
4350 {
4351 warning (OPT_Wattributes, "%qE attribute ignored", name);
4352 *no_add_attrs = true;
4353 }
4354
4355 return NULL_TREE;
4356}
4357
4358
4359/* Handle a "used" attribute; arguments as in
4360 struct attribute_spec.handler. */
4361
4362static tree
4363handle_used_attribute (tree *pnode, tree name, tree ARG_UNUSED (args),
4364 int ARG_UNUSED (flags), bool *no_add_attrs)
4365{
4366 tree node = *pnode;
4367
4368 if (TREE_CODE (node) == FUNCTION_DECL
4369 || (TREE_CODE (node) == VAR_DECL && TREE_STATIC (node)))
4370 {
4371 TREE_USED (node) = 1;
4372 DECL_PRESERVE_P (node) = 1;
4373 }
4374 else
4375 {
4376 warning (OPT_Wattributes, "%qE attribute ignored", name);
4377 *no_add_attrs = true;
4378 }
4379
4380 return NULL_TREE;
4381}
4382
4383/* Handle a "unused" attribute; arguments as in
4384 struct attribute_spec.handler. */
4385
4386static tree
4387handle_unused_attribute (tree *node, tree name, tree ARG_UNUSED (args),
4388 int flags, bool *no_add_attrs)
4389{
4390 if (DECL_P (*node))
4391 {
4392 tree decl = *node;
4393
4394 if (TREE_CODE (decl) == PARM_DECL
4395 || TREE_CODE (decl) == VAR_DECL
4396 || TREE_CODE (decl) == FUNCTION_DECL
4397 || TREE_CODE (decl) == LABEL_DECL
4398 || TREE_CODE (decl) == TYPE_DECL)
4399 TREE_USED (decl) = 1;
4400 else
4401 {
4402 warning (OPT_Wattributes, "%qE attribute ignored", name);
4403 *no_add_attrs = true;
4404 }
4405 }
4406 else
4407 {
4408 if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4409 *node = build_variant_type_copy (*node);
4410 TREE_USED (*node) = 1;
4411 }
4412
4413 return NULL_TREE;
4414}
4415
4416/* Handle a "externally_visible" attribute; arguments as in
4417 struct attribute_spec.handler. */
4418
4419static tree
4420handle_externally_visible_attribute (tree *pnode, tree name,
4421 tree ARG_UNUSED (args),
4422 int ARG_UNUSED (flags),
4423 bool *no_add_attrs)
4424{
4425 tree node = *pnode;
4426
4427 if (TREE_CODE (node) == FUNCTION_DECL || TREE_CODE (node) == VAR_DECL)
4428 {
4429 if ((!TREE_STATIC (node) && TREE_CODE (node) != FUNCTION_DECL
4430 && !DECL_EXTERNAL (node)) || !TREE_PUBLIC (node))
4431 {
4432 warning (OPT_Wattributes,
4433 "%qE attribute have effect only on public objects", name);
4434 *no_add_attrs = true;
4435 }
4436 }
4437 else
4438 {
4439 warning (OPT_Wattributes, "%qE attribute ignored", name);
4440 *no_add_attrs = true;
4441 }
4442
4443 return NULL_TREE;
4444}
4445
4446/* Handle a "const" attribute; arguments as in
4447 struct attribute_spec.handler. */
4448
4449static tree
4450handle_const_attribute (tree *node, tree name, tree ARG_UNUSED (args),
4451 int ARG_UNUSED (flags), bool *no_add_attrs)
4452{
4453 tree type = TREE_TYPE (*node);
4454
4455 /* See FIXME comment on noreturn in c_common_attribute_table. */
4456 if (TREE_CODE (*node) == FUNCTION_DECL)
4457 TREE_READONLY (*node) = 1;
4458 else if (TREE_CODE (type) == POINTER_TYPE
4459 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4460 TREE_TYPE (*node)
4461 = build_pointer_type
4462 (build_type_variant (TREE_TYPE (type), 1,
4463 TREE_THIS_VOLATILE (TREE_TYPE (type))));
4464 else
4465 {
4466 warning (OPT_Wattributes, "%qE attribute ignored", name);
4467 *no_add_attrs = true;
4468 }
4469
4470 return NULL_TREE;
4471}
4472
4473/* Handle a "transparent_union" attribute; arguments as in
4474 struct attribute_spec.handler. */
4475
4476static tree
4477handle_transparent_union_attribute (tree *node, tree name,
4478 tree ARG_UNUSED (args), int flags,
4479 bool *no_add_attrs)
4480{
4481 tree type = NULL;
4482
4483 *no_add_attrs = true;
4484
4485 if (DECL_P (*node))
4486 {
4487 if (TREE_CODE (*node) != TYPE_DECL)
4488 goto ignored;
4489 node = &TREE_TYPE (*node);
4490 type = *node;
4491 }
4492 else if (TYPE_P (*node))
4493 type = *node;
4494 else
4495 goto ignored;
4496
4497 if (TREE_CODE (type) == UNION_TYPE)
4498 {
4499 /* When IN_PLACE is set, leave the check for FIELDS and MODE to
4500 the code in finish_struct. */
4501 if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4502 {
4503 if (TYPE_FIELDS (type) == NULL_TREE
4504 || TYPE_MODE (type) != DECL_MODE (TYPE_FIELDS (type)))
4505 goto ignored;
4506
4507 /* A type variant isn't good enough, since we don't a cast
4508 to such a type removed as a no-op. */
4509 *node = type = build_duplicate_type (type);
4510 }
4511
4512 TYPE_TRANSPARENT_UNION (type) = 1;
4513 return NULL_TREE;
4514 }
4515
4516 ignored:
4517 warning (OPT_Wattributes, "%qE attribute ignored", name);
4518 return NULL_TREE;
4519}
4520
4521/* Handle a "constructor" attribute; arguments as in
4522 struct attribute_spec.handler. */
4523
4524static tree
4525handle_constructor_attribute (tree *node, tree name,
4526 tree ARG_UNUSED (args),
4527 int ARG_UNUSED (flags),
4528 bool *no_add_attrs)
4529{
4530 tree decl = *node;
4531 tree type = TREE_TYPE (decl);
4532
4533 if (TREE_CODE (decl) == FUNCTION_DECL
4534 && TREE_CODE (type) == FUNCTION_TYPE
4535 && decl_function_context (decl) == 0)
4536 {
4537 DECL_STATIC_CONSTRUCTOR (decl) = 1;
4538 TREE_USED (decl) = 1;
4539 }
4540 else
4541 {
4542 warning (OPT_Wattributes, "%qE attribute ignored", name);
4543 *no_add_attrs = true;
4544 }
4545
4546 return NULL_TREE;
4547}
4548
4549/* Handle a "destructor" attribute; arguments as in
4550 struct attribute_spec.handler. */
4551
4552static tree
4553handle_destructor_attribute (tree *node, tree name,
4554 tree ARG_UNUSED (args),
4555 int ARG_UNUSED (flags),
4556 bool *no_add_attrs)
4557{
4558 tree decl = *node;
4559 tree type = TREE_TYPE (decl);
4560
4561 if (TREE_CODE (decl) == FUNCTION_DECL
4562 && TREE_CODE (type) == FUNCTION_TYPE
4563 && decl_function_context (decl) == 0)
4564 {
4565 DECL_STATIC_DESTRUCTOR (decl) = 1;
4566 TREE_USED (decl) = 1;
4567 }
4568 else
4569 {
4570 warning (OPT_Wattributes, "%qE attribute ignored", name);
4571 *no_add_attrs = true;
4572 }
4573
4574 return NULL_TREE;
4575}
4576
4577/* Handle a "mode" attribute; arguments as in
4578 struct attribute_spec.handler. */
4579
4580static tree
4581handle_mode_attribute (tree *node, tree name, tree args,
4582 int ARG_UNUSED (flags), bool *no_add_attrs)
4583{
4584 tree type = *node;
4585
4586 *no_add_attrs = true;
4587
4588 if (TREE_CODE (TREE_VALUE (args)) != IDENTIFIER_NODE)
4589 warning (OPT_Wattributes, "%qE attribute ignored", name);
4590 else
4591 {
4592 int j;
4593 const char *p = IDENTIFIER_POINTER (TREE_VALUE (args));
4594 int len = strlen (p);
4595 enum machine_mode mode = VOIDmode;
4596 tree typefm;
4597 bool valid_mode;
4598
4599 if (len > 4 && p[0] == '_' && p[1] == '_'
4600 && p[len - 1] == '_' && p[len - 2] == '_')
4601 {
4602 char *newp = (char *) alloca (len - 1);
4603
4604 strcpy (newp, &p[2]);
4605 newp[len - 4] = '\0';
4606 p = newp;
4607 }
4608
4609 /* Change this type to have a type with the specified mode.
4610 First check for the special modes. */
4611 if (!strcmp (p, "byte"))
4612 mode = byte_mode;
4613 else if (!strcmp (p, "word"))
4614 mode = word_mode;
4615 else if (!strcmp (p, "pointer"))
4616 mode = ptr_mode;
4617 else
4618 for (j = 0; j < NUM_MACHINE_MODES; j++)
4619 if (!strcmp (p, GET_MODE_NAME (j)))
4620 {
4621 mode = (enum machine_mode) j;
4622 break;
4623 }
4624
4625 if (mode == VOIDmode)
4626 {
4627 error ("unknown machine mode %qs", p);
4628 return NULL_TREE;
4629 }
4630
4631 valid_mode = false;
4632 switch (GET_MODE_CLASS (mode))
4633 {
4634 case MODE_INT:
4635 case MODE_PARTIAL_INT:
4636 case MODE_FLOAT:
4637 case MODE_DECIMAL_FLOAT:
4638 valid_mode = targetm.scalar_mode_supported_p (mode);
4639 break;
4640
4641 case MODE_COMPLEX_INT:
4642 case MODE_COMPLEX_FLOAT:
4643 valid_mode = targetm.scalar_mode_supported_p (GET_MODE_INNER (mode));
4644 break;
4645
4646 case MODE_VECTOR_INT:
4647 case MODE_VECTOR_FLOAT:
4648 warning (OPT_Wattributes, "specifying vector types with "
4649 "__attribute__ ((mode)) is deprecated");
4650 warning (OPT_Wattributes,
4651 "use __attribute__ ((vector_size)) instead");
4652 valid_mode = vector_mode_valid_p (mode);
4653 break;
4654
4655 default:
4656 break;
4657 }
4658 if (!valid_mode)
4659 {
4660 error ("unable to emulate %qs", p);
4661 return NULL_TREE;
4662 }
4663
4664 if (POINTER_TYPE_P (type))
4665 {
4666 tree (*fn)(tree, enum machine_mode, bool);
4667
4668 if (!targetm.valid_pointer_mode (mode))
4669 {
4670 error ("invalid pointer mode %qs", p);
4671 return NULL_TREE;
4672 }
4673
4674 if (TREE_CODE (type) == POINTER_TYPE)
4675 fn = build_pointer_type_for_mode;
4676 else
4677 fn = build_reference_type_for_mode;
4678 typefm = fn (TREE_TYPE (type), mode, false);
4679 }
4680 else
4681 typefm = lang_hooks.types.type_for_mode (mode, TYPE_UNSIGNED (type));
4682
4683 if (typefm == NULL_TREE)
4684 {
4685 error ("no data type for mode %qs", p);
4686 return NULL_TREE;
4687 }
4688 else if (TREE_CODE (type) == ENUMERAL_TYPE)
4689 {
4690 /* For enumeral types, copy the precision from the integer
4691 type returned above. If not an INTEGER_TYPE, we can't use
4692 this mode for this type. */
4693 if (TREE_CODE (typefm) != INTEGER_TYPE)
4694 {
4695 error ("cannot use mode %qs for enumeral types", p);
4696 return NULL_TREE;
4697 }
4698
4699 if (flags & ATTR_FLAG_TYPE_IN_PLACE)
4700 {
4701 TYPE_PRECISION (type) = TYPE_PRECISION (typefm);
4702 typefm = type;
4703 }
4704 else
4705 {
4706 /* We cannot build a type variant, as there's code that assumes
4707 that TYPE_MAIN_VARIANT has the same mode. This includes the
4708 debug generators. Instead, create a subrange type. This
4709 results in all of the enumeral values being emitted only once
4710 in the original, and the subtype gets them by reference. */
4711 if (TYPE_UNSIGNED (type))
4712 typefm = make_unsigned_type (TYPE_PRECISION (typefm));
4713 else
4714 typefm = make_signed_type (TYPE_PRECISION (typefm));
4715 TREE_TYPE (typefm) = type;
4716 }
4717 }
4718 else if (VECTOR_MODE_P (mode)
4719 ? TREE_CODE (type) != TREE_CODE (TREE_TYPE (typefm))
4720 : TREE_CODE (type) != TREE_CODE (typefm))
4721 {
4722 error ("mode %qs applied to inappropriate type", p);
4723 return NULL_TREE;
4724 }
4725
4726 *node = typefm;
4727 }
4728
4729 return NULL_TREE;
4730}
4731
4732/* Handle a "section" attribute; arguments as in
4733 struct attribute_spec.handler. */
4734
4735static tree
4736handle_section_attribute (tree *node, tree ARG_UNUSED (name), tree args,
4737 int ARG_UNUSED (flags), bool *no_add_attrs)
4738{
4739 tree decl = *node;
4740
4741 if (targetm.have_named_sections)
4742 {
4743 user_defined_section_attribute = true;
4744
4745 if ((TREE_CODE (decl) == FUNCTION_DECL
4746 || TREE_CODE (decl) == VAR_DECL)
4747 && TREE_CODE (TREE_VALUE (args)) == STRING_CST)
4748 {
4749 if (TREE_CODE (decl) == VAR_DECL
4750 && current_function_decl != NULL_TREE
4751 && !TREE_STATIC (decl))
4752 {
4753 error ("%Jsection attribute cannot be specified for "
4754 "local variables", decl);
4755 *no_add_attrs = true;
4756 }
4757
4758 /* The decl may have already been given a section attribute
4759 from a previous declaration. Ensure they match. */
4760 else if (DECL_SECTION_NAME (decl) != NULL_TREE
4761 && strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME (decl)),
4762 TREE_STRING_POINTER (TREE_VALUE (args))) != 0)
4763 {
4764 error ("section of %q+D conflicts with previous declaration",
4765 *node);
4766 *no_add_attrs = true;
4767 }
4768 else
4769 DECL_SECTION_NAME (decl) = TREE_VALUE (args);
4770 }
4771 else
4772 {
4773 error ("section attribute not allowed for %q+D", *node);
4774 *no_add_attrs = true;
4775 }
4776 }
4777 else
4778 {
4779 error ("%Jsection attributes are not supported for this target", *node);
4780 *no_add_attrs = true;
4781 }
4782
4783 return NULL_TREE;
4784}
4785
4786/* Handle a "aligned" attribute; arguments as in
4787 struct attribute_spec.handler. */
4788
4789static tree
4790handle_aligned_attribute (tree *node, tree ARG_UNUSED (name), tree args,
4791 int flags, bool *no_add_attrs)
4792{
4793 tree decl = NULL_TREE;
4794 tree *type = NULL;
4795 int is_type = 0;
4796 tree align_expr = (args ? TREE_VALUE (args)
4797 : size_int (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
4798 int i;
4799
4800 if (DECL_P (*node))
4801 {
4802 decl = *node;
4803 type = &TREE_TYPE (decl);
4804 is_type = TREE_CODE (*node) == TYPE_DECL;
4805 }
4806 else if (TYPE_P (*node))
4807 type = node, is_type = 1;
4808
4809 if (TREE_CODE (align_expr) != INTEGER_CST)
4810 {
4811 error ("requested alignment is not a constant");
4812 *no_add_attrs = true;
4813 }
4814 else if ((i = tree_log2 (align_expr)) == -1)
4815 {
4816 error ("requested alignment is not a power of 2");
4817 *no_add_attrs = true;
4818 }
4819 else if (i > HOST_BITS_PER_INT - 2)
4820 {
4821 error ("requested alignment is too large");
4822 *no_add_attrs = true;
4823 }
4824 else if (is_type)
4825 {
4826 /* If we have a TYPE_DECL, then copy the type, so that we
4827 don't accidentally modify a builtin type. See pushdecl. */
4828 if (decl && TREE_TYPE (decl) != error_mark_node
4829 && DECL_ORIGINAL_TYPE (decl) == NULL_TREE)
4830 {
4831 tree tt = TREE_TYPE (decl);
4832 *type = build_variant_type_copy (*type);
4833 DECL_ORIGINAL_TYPE (decl) = tt;
4834 TYPE_NAME (*type) = decl;
4835 TREE_USED (*type) = TREE_USED (decl);
4836 TREE_TYPE (decl) = *type;
4837 }
4838 else if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
4839 *type = build_variant_type_copy (*type);
4840
4841 TYPE_ALIGN (*type) = (1 << i) * BITS_PER_UNIT;
4842 TYPE_USER_ALIGN (*type) = 1;
4843 }
4844 else if (! VAR_OR_FUNCTION_DECL_P (decl)
4845 && TREE_CODE (decl) != FIELD_DECL)
4846 {
4847 error ("alignment may not be specified for %q+D", decl);
4848 *no_add_attrs = true;
4849 }
4850 else if (TREE_CODE (decl) == FUNCTION_DECL
4851 && DECL_ALIGN (decl) > (1 << i) * BITS_PER_UNIT)
4852 {
4853 if (DECL_USER_ALIGN (decl))
4854 error ("alignment for %q+D was previously specified as %d "
4855 "and may not be decreased", decl,
4856 DECL_ALIGN (decl) / BITS_PER_UNIT);
4857 else
4858 error ("alignment for %q+D must be at least %d", decl,
4859 DECL_ALIGN (decl) / BITS_PER_UNIT);
4860 *no_add_attrs = true;
4861 }
4862 else
4863 {
4864 DECL_ALIGN (decl) = (1 << i) * BITS_PER_UNIT;
4865 DECL_USER_ALIGN (decl) = 1;
4866 }
4867
4868 return NULL_TREE;
4869}
4870
4871/* Handle a "weak" attribute; arguments as in
4872 struct attribute_spec.handler. */
4873
4874static tree
4875handle_weak_attribute (tree *node, tree name,
4876 tree ARG_UNUSED (args),
4877 int ARG_UNUSED (flags),
4878 bool * ARG_UNUSED (no_add_attrs))
4879{
4880 if (TREE_CODE (*node) == FUNCTION_DECL
4881 || TREE_CODE (*node) == VAR_DECL)
4882 declare_weak (*node);
4883 else
4884 warning (OPT_Wattributes, "%qE attribute ignored", name);
4885
4886
4887 return NULL_TREE;
4888}
4889
4890/* Handle an "alias" attribute; arguments as in
4891 struct attribute_spec.handler. */
4892
4893static tree
4894handle_alias_attribute (tree *node, tree name, tree args,
4895 int ARG_UNUSED (flags), bool *no_add_attrs)
4896{
4897 tree decl = *node;
4898
4899 if ((TREE_CODE (decl) == FUNCTION_DECL && DECL_INITIAL (decl))
4900 || (TREE_CODE (decl) != FUNCTION_DECL
4901 && TREE_PUBLIC (decl) && !DECL_EXTERNAL (decl))
4902 /* A static variable declaration is always a tentative definition,
4903 but the alias is a non-tentative definition which overrides. */
4904 || (TREE_CODE (decl) != FUNCTION_DECL
4905 && ! TREE_PUBLIC (decl) && DECL_INITIAL (decl)))
4906 {
4907 error ("%q+D defined both normally and as an alias", decl);
4908 *no_add_attrs = true;
4909 }
4910
4911 /* Note that the very first time we process a nested declaration,
4912 decl_function_context will not be set. Indeed, *would* never
4913 be set except for the DECL_INITIAL/DECL_EXTERNAL frobbery that
4914 we do below. After such frobbery, pushdecl would set the context.
4915 In any case, this is never what we want. */
4916 else if (decl_function_context (decl) == 0 && current_function_decl == NULL)
4917 {
4918 tree id;
4919
4920 id = TREE_VALUE (args);
4921 if (TREE_CODE (id) != STRING_CST)
4922 {
4923 error ("alias argument not a string");
4924 *no_add_attrs = true;
4925 return NULL_TREE;
4926 }
4927 id = get_identifier (TREE_STRING_POINTER (id));
4928 /* This counts as a use of the object pointed to. */
4929 TREE_USED (id) = 1;
4930
4931 if (TREE_CODE (decl) == FUNCTION_DECL)
4932 DECL_INITIAL (decl) = error_mark_node;
4933 else
4934 {
4935 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
4936 DECL_EXTERNAL (decl) = 1;
4937 else
4938 DECL_EXTERNAL (decl) = 0;
4939 TREE_STATIC (decl) = 1;
4940 }
4941 }
4942 else
4943 {
4944 warning (OPT_Wattributes, "%qE attribute ignored", name);
4945 *no_add_attrs = true;
4946 }
4947
4948 return NULL_TREE;
4949}
4950
4951/* Handle a "weakref" attribute; arguments as in struct
4952 attribute_spec.handler. */
4953
4954static tree
4955handle_weakref_attribute (tree *node, tree ARG_UNUSED (name), tree args,
4956 int flags, bool *no_add_attrs)
4957{
4958 tree attr = NULL_TREE;
4959
4960 /* We must ignore the attribute when it is associated with
4961 local-scoped decls, since attribute alias is ignored and many
4962 such symbols do not even have a DECL_WEAK field. */
4963 if (decl_function_context (*node) || current_function_decl)
4964 {
4965 warning (OPT_Wattributes, "%qE attribute ignored", name);
4966 *no_add_attrs = true;
4967 return NULL_TREE;
4968 }
4969
4970 /* The idea here is that `weakref("name")' mutates into `weakref,
4971 alias("name")', and weakref without arguments, in turn,
4972 implicitly adds weak. */
4973
4974 if (args)
4975 {
4976 attr = tree_cons (get_identifier ("alias"), args, attr);
4977 attr = tree_cons (get_identifier ("weakref"), NULL_TREE, attr);
4978
4979 *no_add_attrs = true;
4980
4981 decl_attributes (node, attr, flags);
4982 }
4983 else
4984 {
4985 if (lookup_attribute ("alias", DECL_ATTRIBUTES (*node)))
4986 error ("%Jweakref attribute must appear before alias attribute",
4987 *node);
4988
4989 /* Can't call declare_weak because it wants this to be TREE_PUBLIC,
4990 and that isn't supported; and because it wants to add it to
4991 the list of weak decls, which isn't helpful. */
4992 DECL_WEAK (*node) = 1;
4993 }
4994
4995 return NULL_TREE;
4996}
4997
4998/* Handle an "visibility" attribute; arguments as in
4999 struct attribute_spec.handler. */
5000
5001static tree
5002handle_visibility_attribute (tree *node, tree name, tree args,
5003 int ARG_UNUSED (flags),
5004 bool *ARG_UNUSED (no_add_attrs))
5005{
5006 tree decl = *node;
5007 tree id = TREE_VALUE (args);
5008 enum symbol_visibility vis;
5009
5010 if (TYPE_P (*node))
5011 {
5012 if (TREE_CODE (*node) == ENUMERAL_TYPE)
5013 /* OK */;
5014 else if (TREE_CODE (*node) != RECORD_TYPE && TREE_CODE (*node) != UNION_TYPE)
5015 {
5016 warning (OPT_Wattributes, "%qE attribute ignored on non-class types",
5017 name);
5018 return NULL_TREE;
5019 }
5020 else if (TYPE_FIELDS (*node))
5021 {
5022 error ("%qE attribute ignored because %qT is already defined",
5023 name, *node);
5024 return NULL_TREE;
5025 }
5026 }
5027 else if (decl_function_context (decl) != 0 || !TREE_PUBLIC (decl))
5028 {
5029 warning (OPT_Wattributes, "%qE attribute ignored", name);
5030 return NULL_TREE;
5031 }
5032
5033 if (TREE_CODE (id) != STRING_CST)
5034 {
5035 error ("visibility argument not a string");
5036 return NULL_TREE;
5037 }
5038
5039 /* If this is a type, set the visibility on the type decl. */
5040 if (TYPE_P (decl))
5041 {
5042 decl = TYPE_NAME (decl);
5043 if (!decl)
5044 return NULL_TREE;
5045 if (TREE_CODE (decl) == IDENTIFIER_NODE)
5046 {
5047 warning (OPT_Wattributes, "%qE attribute ignored on types",
5048 name);
5049 return NULL_TREE;
5050 }
5051 }
5052
5053 if (strcmp (TREE_STRING_POINTER (id), "default") == 0)
5054 vis = VISIBILITY_DEFAULT;
5055 else if (strcmp (TREE_STRING_POINTER (id), "internal") == 0)
5056 vis = VISIBILITY_INTERNAL;
5057 else if (strcmp (TREE_STRING_POINTER (id), "hidden") == 0)
5058 vis = VISIBILITY_HIDDEN;
5059 else if (strcmp (TREE_STRING_POINTER (id), "protected") == 0)
5060 vis = VISIBILITY_PROTECTED;
5061 else
5062 {
5063 error ("visibility argument must be one of \"default\", \"hidden\", \"protected\" or \"internal\"");
5064 vis = VISIBILITY_DEFAULT;
5065 }
5066
5067 if (DECL_VISIBILITY_SPECIFIED (decl)
5068 && vis != DECL_VISIBILITY (decl)
5069 && lookup_attribute ("visibility", (TYPE_P (*node)
5070 ? TYPE_ATTRIBUTES (*node)
5071 : DECL_ATTRIBUTES (decl))))
5072 error ("%qD redeclared with different visibility", decl);
5073
5074 DECL_VISIBILITY (decl) = vis;
5075 DECL_VISIBILITY_SPECIFIED (decl) = 1;
5076
5077 /* Go ahead and attach the attribute to the node as well. This is needed
5078 so we can determine whether we have VISIBILITY_DEFAULT because the
5079 visibility was not specified, or because it was explicitly overridden
5080 from the containing scope. */
5081
5082 return NULL_TREE;
5083}
5084
5085/* Determine the ELF symbol visibility for DECL, which is either a
5086 variable or a function. It is an error to use this function if a
5087 definition of DECL is not available in this translation unit.
5088 Returns true if the final visibility has been determined by this
5089 function; false if the caller is free to make additional
5090 modifications. */
5091
5092bool
5093c_determine_visibility (tree decl)
5094{
5095 gcc_assert (TREE_CODE (decl) == VAR_DECL
5096 || TREE_CODE (decl) == FUNCTION_DECL);
5097
5098 /* If the user explicitly specified the visibility with an
5099 attribute, honor that. DECL_VISIBILITY will have been set during
5100 the processing of the attribute. We check for an explicit
5101 attribute, rather than just checking DECL_VISIBILITY_SPECIFIED,
5102 to distinguish the use of an attribute from the use of a "#pragma
5103 GCC visibility push(...)"; in the latter case we still want other
5104 considerations to be able to overrule the #pragma. */
5105 if (lookup_attribute ("visibility", DECL_ATTRIBUTES (decl)))
5106 return true;
5107
5108 /* Anything that is exported must have default visibility. */
5109 if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
5110 && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl)))
5111 {
5112 DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT;
5113 DECL_VISIBILITY_SPECIFIED (decl) = 1;
5114 return true;
5115 }
5116
5117 /* Set default visibility to whatever the user supplied with
5118 visibility_specified depending on #pragma GCC visibility. */
5119 if (!DECL_VISIBILITY_SPECIFIED (decl))
5120 {
5121 DECL_VISIBILITY (decl) = default_visibility;
5122 DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma;
5123 }
5124 return false;
5125}
5126
5127/* Handle an "tls_model" attribute; arguments as in
5128 struct attribute_spec.handler. */
5129
5130static tree
5131handle_tls_model_attribute (tree *node, tree name, tree args,
5132 int ARG_UNUSED (flags), bool *no_add_attrs)
5133{
5134 tree id;
5135 tree decl = *node;
5136 enum tls_model kind;
5137
5138 *no_add_attrs = true;
5139
5140 if (!DECL_THREAD_LOCAL_P (decl))
5141 {
5142 warning (OPT_Wattributes, "%qE attribute ignored", name);
5143 return NULL_TREE;
5144 }
5145
5146 kind = DECL_TLS_MODEL (decl);
5147 id = TREE_VALUE (args);
5148 if (TREE_CODE (id) != STRING_CST)
5149 {
5150 error ("tls_model argument not a string");
5151 return NULL_TREE;
5152 }
5153
5154 if (!strcmp (TREE_STRING_POINTER (id), "local-exec"))
5155 kind = TLS_MODEL_LOCAL_EXEC;
5156 else if (!strcmp (TREE_STRING_POINTER (id), "initial-exec"))
5157 kind = TLS_MODEL_INITIAL_EXEC;
5158 else if (!strcmp (TREE_STRING_POINTER (id), "local-dynamic"))
5159 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC;
5160 else if (!strcmp (TREE_STRING_POINTER (id), "global-dynamic"))
5161 kind = TLS_MODEL_GLOBAL_DYNAMIC;
5162 else
5163 error ("tls_model argument must be one of \"local-exec\", \"initial-exec\", \"local-dynamic\" or \"global-dynamic\"");
5164
5165 DECL_TLS_MODEL (decl) = kind;
5166 return NULL_TREE;
5167}
5168
5169/* Handle a "no_instrument_function" attribute; arguments as in
5170 struct attribute_spec.handler. */
5171
5172static tree
5173handle_no_instrument_function_attribute (tree *node, tree name,
5174 tree ARG_UNUSED (args),
5175 int ARG_UNUSED (flags),
5176 bool *no_add_attrs)
5177{
5178 tree decl = *node;
5179
5180 if (TREE_CODE (decl) != FUNCTION_DECL)
5181 {
5182 error ("%J%qE attribute applies only to functions", decl, name);
5183 *no_add_attrs = true;
5184 }
5185 else if (DECL_INITIAL (decl))
5186 {
5187 error ("%Jcan%'t set %qE attribute after definition", decl, name);
5188 *no_add_attrs = true;
5189 }
5190 else
5191 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1;
5192
5193 return NULL_TREE;
5194}
5195
5196/* Handle a "malloc" attribute; arguments as in
5197 struct attribute_spec.handler. */
5198
5199static tree
5200handle_malloc_attribute (tree *node, tree name, tree ARG_UNUSED (args),
5201 int ARG_UNUSED (flags), bool *no_add_attrs)
5202{
5203 if (TREE_CODE (*node) == FUNCTION_DECL
5204 && POINTER_TYPE_P (TREE_TYPE (TREE_TYPE (*node))))
5205 DECL_IS_MALLOC (*node) = 1;
5206 else
5207 {
5208 warning (OPT_Wattributes, "%qE attribute ignored", name);
5209 *no_add_attrs = true;
5210 }
5211
5212 return NULL_TREE;
5213}
5214
5215/* Handle a "returns_twice" attribute; arguments as in
5216 struct attribute_spec.handler. */
5217
5218static tree
5219handle_returns_twice_attribute (tree *node, tree name, tree ARG_UNUSED (args),
5220 int ARG_UNUSED (flags), bool *no_add_attrs)
5221{
5222 if (TREE_CODE (*node) == FUNCTION_DECL)
5223 DECL_IS_RETURNS_TWICE (*node) = 1;
5224 else
5225 {
5226 warning (OPT_Wattributes, "%qE attribute ignored", name);
5227 *no_add_attrs = true;
5228 }
5229
5230 return NULL_TREE;
5231}
5232
5233/* Handle a "no_limit_stack" attribute; arguments as in
5234 struct attribute_spec.handler. */
5235
5236static tree
5237handle_no_limit_stack_attribute (tree *node, tree name,
5238 tree ARG_UNUSED (args),
5239 int ARG_UNUSED (flags),
5240 bool *no_add_attrs)
5241{
5242 tree decl = *node;
5243
5244 if (TREE_CODE (decl) != FUNCTION_DECL)
5245 {
5246 error ("%J%qE attribute applies only to functions", decl, name);
5247 *no_add_attrs = true;
5248 }
5249 else if (DECL_INITIAL (decl))
5250 {
5251 error ("%Jcan%'t set %qE attribute after definition", decl, name);
5252 *no_add_attrs = true;
5253 }
5254 else
5255 DECL_NO_LIMIT_STACK (decl) = 1;
5256
5257 return NULL_TREE;
5258}
5259
5260/* Handle a "pure" attribute; arguments as in
5261 struct attribute_spec.handler. */
5262
5263static tree
5264handle_pure_attribute (tree *node, tree name, tree ARG_UNUSED (args),
5265 int ARG_UNUSED (flags), bool *no_add_attrs)
5266{
5267 if (TREE_CODE (*node) == FUNCTION_DECL)
5268 DECL_IS_PURE (*node) = 1;
5269 /* ??? TODO: Support types. */
5270 else
5271 {
5272 warning (OPT_Wattributes, "%qE attribute ignored", name);
5273 *no_add_attrs = true;
5274 }
5275
5276 return NULL_TREE;
5277}
5278
5279/* Handle a "no vops" attribute; arguments as in
5280 struct attribute_spec.handler. */
5281
5282static tree
5283handle_novops_attribute (tree *node, tree ARG_UNUSED (name),
5284 tree ARG_UNUSED (args), int ARG_UNUSED (flags),
5285 bool *ARG_UNUSED (no_add_attrs))
5286{
5287 gcc_assert (TREE_CODE (*node) == FUNCTION_DECL);
5288 DECL_IS_NOVOPS (*node) = 1;
5289 return NULL_TREE;
5290}
5291
5292/* Handle a "deprecated" attribute; arguments as in
5293 struct attribute_spec.handler. */
5294
5295static tree
5296handle_deprecated_attribute (tree *node, tree name,
5297 tree ARG_UNUSED (args), int flags,
5298 bool *no_add_attrs)
5299{
5300 tree type = NULL_TREE;
5301 int warn = 0;
5302 tree what = NULL_TREE;
5303
5304 if (DECL_P (*node))
5305 {
5306 tree decl = *node;
5307 type = TREE_TYPE (decl);
5308
5309 if (TREE_CODE (decl) == TYPE_DECL
5310 || TREE_CODE (decl) == PARM_DECL
5311 || TREE_CODE (decl) == VAR_DECL
5312 || TREE_CODE (decl) == FUNCTION_DECL
5313 || TREE_CODE (decl) == FIELD_DECL)
5314 TREE_DEPRECATED (decl) = 1;
5315 else
5316 warn = 1;
5317 }
5318 else if (TYPE_P (*node))
5319 {
5320 if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE))
5321 *node = build_variant_type_copy (*node);
5322 TREE_DEPRECATED (*node) = 1;
5323 type = *node;
5324 }
5325 else
5326 warn = 1;
5327
5328 if (warn)
5329 {
5330 *no_add_attrs = true;
5331 if (type && TYPE_NAME (type))
5332 {
5333 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
5334 what = TYPE_NAME (*node);
5335 else if (TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
5336 && DECL_NAME (TYPE_NAME (type)))
5337 what = DECL_NAME (TYPE_NAME (type));
5338 }
5339 if (what)
5340 warning (OPT_Wattributes, "%qE attribute ignored for %qE", name, what);
5341 else
5342 warning (OPT_Wattributes, "%qE attribute ignored", name);
5343 }
5344
5345 return NULL_TREE;
5346}
5347
5348/* Handle a "vector_size" attribute; arguments as in
5349 struct attribute_spec.handler. */
5350
5351static tree
5352handle_vector_size_attribute (tree *node, tree name, tree args,
5353 int ARG_UNUSED (flags),
5354 bool *no_add_attrs)
5355{
5356 unsigned HOST_WIDE_INT vecsize, nunits;
5357 enum machine_mode orig_mode;
5358 tree type = *node, new_type, size;
5359
5360 *no_add_attrs = true;
5361
5362 size = TREE_VALUE (args);
5363
5364 if (!host_integerp (size, 1))
5365 {
5366 warning (OPT_Wattributes, "%qE attribute ignored", name);
5367 return NULL_TREE;
5368 }
5369
5370 /* Get the vector size (in bytes). */
5371 vecsize = tree_low_cst (size, 1);
5372
5373 /* We need to provide for vector pointers, vector arrays, and
5374 functions returning vectors. For example:
5375
5376 __attribute__((vector_size(16))) short *foo;
5377
5378 In this case, the mode is SI, but the type being modified is
5379 HI, so we need to look further. */
5380
5381 while (POINTER_TYPE_P (type)
5382 || TREE_CODE (type) == FUNCTION_TYPE
5383 || TREE_CODE (type) == METHOD_TYPE
5384 || TREE_CODE (type) == ARRAY_TYPE)
5385 type = TREE_TYPE (type);
5386
5387 /* Get the mode of the type being modified. */
5388 orig_mode = TYPE_MODE (type);
5389
5390 if (TREE_CODE (type) == RECORD_TYPE
5391 || TREE_CODE (type) == UNION_TYPE
5392 || TREE_CODE (type) == VECTOR_TYPE
5393 || (!SCALAR_FLOAT_MODE_P (orig_mode)
5394 && GET_MODE_CLASS (orig_mode) != MODE_INT)
5395 || !host_integerp (TYPE_SIZE_UNIT (type), 1))
5396 {
5397 error ("invalid vector type for attribute %qE", name);
5398 return NULL_TREE;
5399 }
5400
5401 if (vecsize % tree_low_cst (TYPE_SIZE_UNIT (type), 1))
5402 {
5403 error ("vector size not an integral multiple of component size");
5404 return NULL;
5405 }
5406
5407 if (vecsize == 0)
5408 {
5409 error ("zero vector size");
5410 return NULL;
5411 }
5412
5413 /* Calculate how many units fit in the vector. */
5414 nunits = vecsize / tree_low_cst (TYPE_SIZE_UNIT (type), 1);
5415 if (nunits & (nunits - 1))
5416 {
5417 error ("number of components of the vector not a power of two");
5418 return NULL_TREE;
5419 }
5420
5421 new_type = build_vector_type (type, nunits);
5422
5423 /* Build back pointers if needed. */
5424 *node = reconstruct_complex_type (*node, new_type);
5425
5426 return NULL_TREE;
5427}
5428
5429/* Handle the "nonnull" attribute. */
5430static tree
5431handle_nonnull_attribute (tree *node, tree ARG_UNUSED (name),
5432 tree args, int ARG_UNUSED (flags),
5433 bool *no_add_attrs)
5434{
5435 tree type = *node;
5436 unsigned HOST_WIDE_INT attr_arg_num;
5437
5438 /* If no arguments are specified, all pointer arguments should be
5439 non-null. Verify a full prototype is given so that the arguments
5440 will have the correct types when we actually check them later. */
5441 if (!args)
5442 {
5443 if (!TYPE_ARG_TYPES (type))
5444 {
5445 error ("nonnull attribute without arguments on a non-prototype");
5446 *no_add_attrs = true;
5447 }
5448 return NULL_TREE;
5449 }
5450
5451 /* Argument list specified. Verify that each argument number references
5452 a pointer argument. */
5453 for (attr_arg_num = 1; args; args = TREE_CHAIN (args))
5454 {
5455 tree argument;
5456 unsigned HOST_WIDE_INT arg_num = 0, ck_num;
5457
5458 if (!get_nonnull_operand (TREE_VALUE (args), &arg_num))
5459 {
5460 error ("nonnull argument has invalid operand number (argument %lu)",
5461 (unsigned long) attr_arg_num);
5462 *no_add_attrs = true;
5463 return NULL_TREE;
5464 }
5465
5466 argument = TYPE_ARG_TYPES (type);
5467 if (argument)
5468 {
5469 for (ck_num = 1; ; ck_num++)
5470 {
5471 if (!argument || ck_num == arg_num)
5472 break;
5473 argument = TREE_CHAIN (argument);
5474 }
5475
5476 if (!argument
5477 || TREE_CODE (TREE_VALUE (argument)) == VOID_TYPE)
5478 {
5479 error ("nonnull argument with out-of-range operand number (argument %lu, operand %lu)",
5480 (unsigned long) attr_arg_num, (unsigned long) arg_num);
5481 *no_add_attrs = true;
5482 return NULL_TREE;
5483 }
5484
5485 if (TREE_CODE (TREE_VALUE (argument)) != POINTER_TYPE)
5486 {
5487 error ("nonnull argument references non-pointer operand (argument %lu, operand %lu)",
5488 (unsigned long) attr_arg_num, (unsigned long) arg_num);
5489 *no_add_attrs = true;
5490 return NULL_TREE;
5491 }
5492 }
5493 }
5494
5495 return NULL_TREE;
5496}
5497
5498/* Check the argument list of a function call for null in argument slots
5499 that are marked as requiring a non-null pointer argument. */
5500
5501static void
5502check_function_nonnull (tree attrs, tree params)
5503{
5504 tree a, args, param;
5505 int param_num;
5506
5507 for (a = attrs; a; a = TREE_CHAIN (a))
5508 {
5509 if (is_attribute_p ("nonnull", TREE_PURPOSE (a)))
5510 {
5511 args = TREE_VALUE (a);
5512
5513 /* Walk the argument list. If we encounter an argument number we
5514 should check for non-null, do it. If the attribute has no args,
5515 then every pointer argument is checked (in which case the check
5516 for pointer type is done in check_nonnull_arg). */
5517 for (param = params, param_num = 1; ;
5518 param_num++, param = TREE_CHAIN (param))
5519 {
5520 if (!param)
5521 break;
5522 if (!args || nonnull_check_p (args, param_num))
5523 check_function_arguments_recurse (check_nonnull_arg, NULL,
5524 TREE_VALUE (param),
5525 param_num);
5526 }
5527 }
5528 }
5529}
5530
5531/* Check that the Nth argument of a function call (counting backwards
5532 from the end) is a (pointer)0. */
5533
5534static void
5535check_function_sentinel (tree attrs, tree params, tree typelist)
5536{
5537 tree attr = lookup_attribute ("sentinel", attrs);
5538
5539 if (attr)
5540 {
5541 /* Skip over the named arguments. */
5542 while (typelist && params)
5543 {
5544 typelist = TREE_CHAIN (typelist);
5545 params = TREE_CHAIN (params);
5546 }
5547
5548 if (typelist || !params)
5549 warning (OPT_Wformat,
5550 "not enough variable arguments to fit a sentinel");
5551 else
5552 {
5553 tree sentinel, end;
5554 unsigned pos = 0;
5555
5556 if (TREE_VALUE (attr))
5557 {
5558 tree p = TREE_VALUE (TREE_VALUE (attr));
5559 pos = TREE_INT_CST_LOW (p);
5560 }
5561
5562 sentinel = end = params;
5563
5564 /* Advance `end' ahead of `sentinel' by `pos' positions. */
5565 while (pos > 0 && TREE_CHAIN (end))
5566 {
5567 pos--;
5568 end = TREE_CHAIN (end);
5569 }
5570 if (pos > 0)
5571 {
5572 warning (OPT_Wformat,
5573 "not enough variable arguments to fit a sentinel");
5574 return;
5575 }
5576
5577 /* Now advance both until we find the last parameter. */
5578 while (TREE_CHAIN (end))
5579 {
5580 end = TREE_CHAIN (end);
5581 sentinel = TREE_CHAIN (sentinel);
5582 }
5583
5584 /* Validate the sentinel. */
5585 if ((!POINTER_TYPE_P (TREE_TYPE (TREE_VALUE (sentinel)))
5586 || !integer_zerop (TREE_VALUE (sentinel)))
5587 /* Although __null (in C++) is only an integer we allow it
5588 nevertheless, as we are guaranteed that it's exactly
5589 as wide as a pointer, and we don't want to force
5590 users to cast the NULL they have written there.
5591 We warn with -Wstrict-null-sentinel, though. */
5592 && (warn_strict_null_sentinel
5593 || null_node != TREE_VALUE (sentinel)))
5594 warning (OPT_Wformat, "missing sentinel in function call");
5595 }
5596 }
5597}
5598
5599/* Helper for check_function_nonnull; given a list of operands which
5600 must be non-null in ARGS, determine if operand PARAM_NUM should be
5601 checked. */
5602
5603static bool
5604nonnull_check_p (tree args, unsigned HOST_WIDE_INT param_num)
5605{
5606 unsigned HOST_WIDE_INT arg_num = 0;
5607
5608 for (; args; args = TREE_CHAIN (args))
5609 {
5610 bool found = get_nonnull_operand (TREE_VALUE (args), &arg_num);
5611
5612 gcc_assert (found);
5613
5614 if (arg_num == param_num)
5615 return true;
5616 }
5617 return false;
5618}
5619
5620/* Check that the function argument PARAM (which is operand number
5621 PARAM_NUM) is non-null. This is called by check_function_nonnull
5622 via check_function_arguments_recurse. */
5623
5624static void
5625check_nonnull_arg (void * ARG_UNUSED (ctx), tree param,
5626 unsigned HOST_WIDE_INT param_num)
5627{
5628 /* Just skip checking the argument if it's not a pointer. This can
5629 happen if the "nonnull" attribute was given without an operand
5630 list (which means to check every pointer argument). */
5631
5632 if (TREE_CODE (TREE_TYPE (param)) != POINTER_TYPE)
5633 return;
5634
5635 if (integer_zerop (param))
5636 warning (OPT_Wnonnull, "null argument where non-null required "
5637 "(argument %lu)", (unsigned long) param_num);
5638}
5639
5640/* Helper for nonnull attribute handling; fetch the operand number
5641 from the attribute argument list. */
5642
5643static bool
5644get_nonnull_operand (tree arg_num_expr, unsigned HOST_WIDE_INT *valp)
5645{
5646 /* Verify the arg number is a constant. */
5647 if (TREE_CODE (arg_num_expr) != INTEGER_CST
5648 || TREE_INT_CST_HIGH (arg_num_expr) != 0)
5649 return false;
5650
5651 *valp = TREE_INT_CST_LOW (arg_num_expr);
5652 return true;
5653}
5654
5655/* Handle a "nothrow" attribute; arguments as in
5656 struct attribute_spec.handler. */
5657
5658static tree
5659handle_nothrow_attribute (tree *node, tree name, tree ARG_UNUSED (args),
5660 int ARG_UNUSED (flags), bool *no_add_attrs)
5661{
5662 if (TREE_CODE (*node) == FUNCTION_DECL)
5663 TREE_NOTHROW (*node) = 1;
5664 /* ??? TODO: Support types. */
5665 else
5666 {
5667 warning (OPT_Wattributes, "%qE attribute ignored", name);
5668 *no_add_attrs = true;
5669 }
5670
5671 return NULL_TREE;
5672}
5673
5674/* Handle a "cleanup" attribute; arguments as in
5675 struct attribute_spec.handler. */
5676
5677static tree
5678handle_cleanup_attribute (tree *node, tree name, tree args,
5679 int ARG_UNUSED (flags), bool *no_add_attrs)
5680{
5681 tree decl = *node;
5682 tree cleanup_id, cleanup_decl;
5683
5684 /* ??? Could perhaps support cleanups on TREE_STATIC, much like we do
5685 for global destructors in C++. This requires infrastructure that
5686 we don't have generically at the moment. It's also not a feature
5687 we'd be missing too much, since we do have attribute constructor. */
5688 if (TREE_CODE (decl) != VAR_DECL || TREE_STATIC (decl))
5689 {
5690 warning (OPT_Wattributes, "%qE attribute ignored", name);
5691 *no_add_attrs = true;
5692 return NULL_TREE;
5693 }
5694
5695 /* Verify that the argument is a function in scope. */
5696 /* ??? We could support pointers to functions here as well, if
5697 that was considered desirable. */
5698 cleanup_id = TREE_VALUE (args);
5699 if (TREE_CODE (cleanup_id) != IDENTIFIER_NODE)
5700 {
5701 error ("cleanup argument not an identifier");
5702 *no_add_attrs = true;
5703 return NULL_TREE;
5704 }
5705 cleanup_decl = lookup_name (cleanup_id);
5706 if (!cleanup_decl || TREE_CODE (cleanup_decl) != FUNCTION_DECL)
5707 {
5708 error ("cleanup argument not a function");
5709 *no_add_attrs = true;
5710 return NULL_TREE;
5711 }
5712
5713 /* That the function has proper type is checked with the
5714 eventual call to build_function_call. */
5715
5716 return NULL_TREE;
5717}
5718
5719/* Handle a "warn_unused_result" attribute. No special handling. */
5720
5721static tree
5722handle_warn_unused_result_attribute (tree *node, tree name,
5723 tree ARG_UNUSED (args),
5724 int ARG_UNUSED (flags), bool *no_add_attrs)
5725{
5726 /* Ignore the attribute for functions not returning any value. */
5727 if (VOID_TYPE_P (TREE_TYPE (*node)))
5728 {
5729 warning (OPT_Wattributes, "%qE attribute ignored", name);
5730 *no_add_attrs = true;
5731 }
5732
5733 return NULL_TREE;
5734}
5735
5736/* Handle a "sentinel" attribute. */
5737
5738static tree
5739handle_sentinel_attribute (tree *node, tree name, tree args,
5740 int ARG_UNUSED (flags), bool *no_add_attrs)
5741{
5742 tree params = TYPE_ARG_TYPES (*node);
5743
5744 if (!params)
5745 {
5746 warning (OPT_Wattributes,
5747 "%qE attribute requires prototypes with named arguments", name);
5748 *no_add_attrs = true;
5749 }
5750 else
5751 {
5752 while (TREE_CHAIN (params))
5753 params = TREE_CHAIN (params);
5754
5755 if (VOID_TYPE_P (TREE_VALUE (params)))
5756 {
5757 warning (OPT_Wattributes,
5758 "%qE attribute only applies to variadic functions", name);
5759 *no_add_attrs = true;
5760 }
5761 }
5762
5763 if (args)
5764 {
5765 tree position = TREE_VALUE (args);
5766
5767 if (TREE_CODE (position) != INTEGER_CST)
5768 {
5769 warning (0, "requested position is not an integer constant");
5770 *no_add_attrs = true;
5771 }
5772 else
5773 {
5774 if (tree_int_cst_lt (position, integer_zero_node))
5775 {
5776 warning (0, "requested position is less than zero");
5777 *no_add_attrs = true;
5778 }
5779 }
5780 }
5781
5782 return NULL_TREE;
5783}
5784
5785/* Check for valid arguments being passed to a function. */
5786void
5787check_function_arguments (tree attrs, tree params, tree typelist)
5788{
5789 /* Check for null being passed in a pointer argument that must be
5790 non-null. We also need to do this if format checking is enabled. */
5791
5792 if (warn_nonnull)
5793 check_function_nonnull (attrs, params);
5794
5795 /* Check for errors in format strings. */
5796
5797 if (warn_format || warn_missing_format_attribute)
5798 check_function_format (attrs, params);
5799
5800 if (warn_format)
5801 check_function_sentinel (attrs, params, typelist);
5802}
5803
5804/* Generic argument checking recursion routine. PARAM is the argument to
5805 be checked. PARAM_NUM is the number of the argument. CALLBACK is invoked
5806 once the argument is resolved. CTX is context for the callback. */
5807void
5808check_function_arguments_recurse (void (*callback)
5809 (void *, tree, unsigned HOST_WIDE_INT),
5810 void *ctx, tree param,
5811 unsigned HOST_WIDE_INT param_num)
5812{
5813 if ((TREE_CODE (param) == NOP_EXPR || TREE_CODE (param) == CONVERT_EXPR)
5814 && (TYPE_PRECISION (TREE_TYPE (param))
5815 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (param, 0)))))
5816 {
5817 /* Strip coercion. */
5818 check_function_arguments_recurse (callback, ctx,
5819 TREE_OPERAND (param, 0), param_num);
5820 return;
5821 }
5822
5823 if (TREE_CODE (param) == CALL_EXPR)
5824 {
5825 tree type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (param, 0)));
5826 tree attrs;
5827 bool found_format_arg = false;
5828
5829 /* See if this is a call to a known internationalization function
5830 that modifies a format arg. Such a function may have multiple
5831 format_arg attributes (for example, ngettext). */
5832
5833 for (attrs = TYPE_ATTRIBUTES (type);
5834 attrs;
5835 attrs = TREE_CHAIN (attrs))
5836 if (is_attribute_p ("format_arg", TREE_PURPOSE (attrs)))
5837 {
5838 tree inner_args;
5839 tree format_num_expr;
5840 int format_num;
5841 int i;
5842
5843 /* Extract the argument number, which was previously checked
5844 to be valid. */
5845 format_num_expr = TREE_VALUE (TREE_VALUE (attrs));
5846
5847 gcc_assert (TREE_CODE (format_num_expr) == INTEGER_CST
5848 && !TREE_INT_CST_HIGH (format_num_expr));
5849
5850 format_num = TREE_INT_CST_LOW (format_num_expr);
5851
5852 for (inner_args = TREE_OPERAND (param, 1), i = 1;
5853 inner_args != 0;
5854 inner_args = TREE_CHAIN (inner_args), i++)
5855 if (i == format_num)
5856 {
5857 check_function_arguments_recurse (callback, ctx,
5858 TREE_VALUE (inner_args),
5859 param_num);
5860 found_format_arg = true;
5861 break;
5862 }
5863 }
5864
5865 /* If we found a format_arg attribute and did a recursive check,
5866 we are done with checking this argument. Otherwise, we continue
5867 and this will be considered a non-literal. */
5868 if (found_format_arg)
5869 return;
5870 }
5871
5872 if (TREE_CODE (param) == COND_EXPR)
5873 {
5874 /* Check both halves of the conditional expression. */
5875 check_function_arguments_recurse (callback, ctx,
5876 TREE_OPERAND (param, 1), param_num);
5877 check_function_arguments_recurse (callback, ctx,
5878 TREE_OPERAND (param, 2), param_num);
5879 return;
5880 }
5881
5882 (*callback) (ctx, param, param_num);
5883}
5884
5885/* Function to help qsort sort FIELD_DECLs by name order. */
5886
5887int
5888field_decl_cmp (const void *x_p, const void *y_p)
5889{
5890 const tree *const x = (const tree *const) x_p;
5891 const tree *const y = (const tree *const) y_p;
5892
5893 if (DECL_NAME (*x) == DECL_NAME (*y))
5894 /* A nontype is "greater" than a type. */
5895 return (TREE_CODE (*y) == TYPE_DECL) - (TREE_CODE (*x) == TYPE_DECL);
5896 if (DECL_NAME (*x) == NULL_TREE)
5897 return -1;
5898 if (DECL_NAME (*y) == NULL_TREE)
5899 return 1;
5900 if (DECL_NAME (*x) < DECL_NAME (*y))
5901 return -1;
5902 return 1;
5903}
5904
5905static struct {
5906 gt_pointer_operator new_value;
5907 void *cookie;
5908} resort_data;
5909
5910/* This routine compares two fields like field_decl_cmp but using the
5911pointer operator in resort_data. */
5912
5913static int
5914resort_field_decl_cmp (const void *x_p, const void *y_p)
5915{
5916 const tree *const x = (const tree *const) x_p;
5917 const tree *const y = (const tree *const) y_p;
5918
5919 if (DECL_NAME (*x) == DECL_NAME (*y))
5920 /* A nontype is "greater" than a type. */
5921 return (TREE_CODE (*y) == TYPE_DECL) - (TREE_CODE (*x) == TYPE_DECL);
5922 if (DECL_NAME (*x) == NULL_TREE)
5923 return -1;
5924 if (DECL_NAME (*y) == NULL_TREE)
5925 return 1;
5926 {
5927 tree d1 = DECL_NAME (*x);
5928 tree d2 = DECL_NAME (*y);
5929 resort_data.new_value (&d1, resort_data.cookie);
5930 resort_data.new_value (&d2, resort_data.cookie);
5931 if (d1 < d2)
5932 return -1;
5933 }
5934 return 1;
5935}
5936
5937/* Resort DECL_SORTED_FIELDS because pointers have been reordered. */
5938
5939void
5940resort_sorted_fields (void *obj,
5941 void * ARG_UNUSED (orig_obj),
5942 gt_pointer_operator new_value,
5943 void *cookie)
5944{
5945 struct sorted_fields_type *sf = (struct sorted_fields_type *) obj;
5946 resort_data.new_value = new_value;
5947 resort_data.cookie = cookie;
5948 qsort (&sf->elts[0], sf->len, sizeof (tree),
5949 resort_field_decl_cmp);
5950}
5951
5952/* Subroutine of c_parse_error.
5953 Return the result of concatenating LHS and RHS. RHS is really
5954 a string literal, its first character is indicated by RHS_START and
5955 RHS_SIZE is its length (including the terminating NUL character).
5956
5957 The caller is responsible for deleting the returned pointer. */
5958
5959static char *
5960catenate_strings (const char *lhs, const char *rhs_start, int rhs_size)
5961{
5962 const int lhs_size = strlen (lhs);
5963 char *result = XNEWVEC (char, lhs_size + rhs_size);
5964 strncpy (result, lhs, lhs_size);
5965 strncpy (result + lhs_size, rhs_start, rhs_size);
5966 return result;
5967}
5968
5969/* Issue the error given by GMSGID, indicating that it occurred before
5970 TOKEN, which had the associated VALUE. */
5971
5972void
5973c_parse_error (const char *gmsgid, enum cpp_ttype token, tree value)
5974{
5975#define catenate_messages(M1, M2) catenate_strings ((M1), (M2), sizeof (M2))
5976
5977 char *message = NULL;
5978
5979 if (token == CPP_EOF)
5980 message = catenate_messages (gmsgid, " at end of input");
5981 else if (token == CPP_CHAR || token == CPP_WCHAR)
5982 {
5983 unsigned int val = TREE_INT_CST_LOW (value);
5984 const char *const ell = (token == CPP_CHAR) ? "" : "L";
5985 if (val <= UCHAR_MAX && ISGRAPH (val))
5986 message = catenate_messages (gmsgid, " before %s'%c'");
5987 else
5988 message = catenate_messages (gmsgid, " before %s'\\x%x'");
5989
5990 error (message, ell, val);
5991 free (message);
5992 message = NULL;
5993 }
5994 else if (token == CPP_STRING || token == CPP_WSTRING)
5995 message = catenate_messages (gmsgid, " before string constant");
5996 else if (token == CPP_NUMBER)
5997 message = catenate_messages (gmsgid, " before numeric constant");
5998 else if (token == CPP_NAME)
5999 {
6000 message = catenate_messages (gmsgid, " before %qE");
6001 error (message, value);
6002 free (message);
6003 message = NULL;
6004 }
6005 else if (token == CPP_PRAGMA)
6006 message = catenate_messages (gmsgid, " before %<#pragma%>");
6007 else if (token == CPP_PRAGMA_EOL)
6008 message = catenate_messages (gmsgid, " before end of line");
6009 else if (token < N_TTYPES)
6010 {
6011 message = catenate_messages (gmsgid, " before %qs token");
6012 error (message, cpp_type2name (token));
6013 free (message);
6014 message = NULL;
6015 }
6016 else
6017 error (gmsgid, "");
6018
6019 if (message)
6020 {
6021 error (message, "");
6022 free (message);
6023 }
6024#undef catenate_messages
6025}
6026
6027/* Walk a gimplified function and warn for functions whose return value is
6028 ignored and attribute((warn_unused_result)) is set. This is done before
6029 inlining, so we don't have to worry about that. */
6030
6031void
6032c_warn_unused_result (tree *top_p)
6033{
6034 tree t = *top_p;
6035 tree_stmt_iterator i;
6036 tree fdecl, ftype;
6037
6038 switch (TREE_CODE (t))
6039 {
6040 case STATEMENT_LIST:
6041 for (i = tsi_start (*top_p); !tsi_end_p (i); tsi_next (&i))
6042 c_warn_unused_result (tsi_stmt_ptr (i));
6043 break;
6044
6045 case COND_EXPR:
6046 c_warn_unused_result (&COND_EXPR_THEN (t));
6047 c_warn_unused_result (&COND_EXPR_ELSE (t));
6048 break;
6049 case BIND_EXPR:
6050 c_warn_unused_result (&BIND_EXPR_BODY (t));
6051 break;
6052 case TRY_FINALLY_EXPR:
6053 case TRY_CATCH_EXPR:
6054 c_warn_unused_result (&TREE_OPERAND (t, 0));
6055 c_warn_unused_result (&TREE_OPERAND (t, 1));
6056 break;
6057 case CATCH_EXPR:
6058 c_warn_unused_result (&CATCH_BODY (t));
6059 break;
6060 case EH_FILTER_EXPR:
6061 c_warn_unused_result (&EH_FILTER_FAILURE (t));
6062 break;
6063
6064 case CALL_EXPR:
6065 if (TREE_USED (t))
6066 break;
6067
6068 /* This is a naked call, as opposed to a CALL_EXPR nested inside
6069 a MODIFY_EXPR. All calls whose value is ignored should be
6070 represented like this. Look for the attribute. */
6071 fdecl = get_callee_fndecl (t);
6072 if (fdecl)
6073 ftype = TREE_TYPE (fdecl);
6074 else
6075 {
6076 ftype = TREE_TYPE (TREE_OPERAND (t, 0));
6077 /* Look past pointer-to-function to the function type itself. */
6078 ftype = TREE_TYPE (ftype);
6079 }
6080
6081 if (lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (ftype)))
6082 {
6083 if (fdecl)
6084 warning (0, "%Hignoring return value of %qD, "
6085 "declared with attribute warn_unused_result",
6086 EXPR_LOCUS (t), fdecl);
6087 else
6088 warning (0, "%Hignoring return value of function "
6089 "declared with attribute warn_unused_result",
6090 EXPR_LOCUS (t));
6091 }
6092 break;
6093
6094 default:
6095 /* Not a container, not a call, or a call whose value is used. */
6096 break;
6097 }
6098}
6099
6100/* Convert a character from the host to the target execution character
6101 set. cpplib handles this, mostly. */
6102
6103HOST_WIDE_INT
6104c_common_to_target_charset (HOST_WIDE_INT c)
6105{
6106 /* Character constants in GCC proper are sign-extended under -fsigned-char,
6107 zero-extended under -fno-signed-char. cpplib insists that characters
6108 and character constants are always unsigned. Hence we must convert
6109 back and forth. */
6110 cppchar_t uc = ((cppchar_t)c) & ((((cppchar_t)1) << CHAR_BIT)-1);
6111
6112 uc = cpp_host_to_exec_charset (parse_in, uc);
6113
6114 if (flag_signed_char)
6115 return ((HOST_WIDE_INT)uc) << (HOST_BITS_PER_WIDE_INT - CHAR_TYPE_SIZE)
6116 >> (HOST_BITS_PER_WIDE_INT - CHAR_TYPE_SIZE);
6117 else
6118 return uc;
6119}
6120
6121/* Build the result of __builtin_offsetof. EXPR is a nested sequence of
6122 component references, with STOP_REF, or alternatively an INDIRECT_REF of
6123 NULL, at the bottom; much like the traditional rendering of offsetof as a
6124 macro. Returns the folded and properly cast result. */
6125
6126static tree
6127fold_offsetof_1 (tree expr, tree stop_ref)
6128{
6129 enum tree_code code = PLUS_EXPR;
6130 tree base, off, t;
6131
6132 if (expr == stop_ref && TREE_CODE (expr) != ERROR_MARK)
6133 return size_zero_node;
6134
6135 switch (TREE_CODE (expr))
6136 {
6137 case ERROR_MARK:
6138 return expr;
6139
6140 case VAR_DECL:
6141 error ("cannot apply %<offsetof%> to static data member %qD", expr);
6142 return error_mark_node;
6143
6144 case CALL_EXPR:
6145 error ("cannot apply %<offsetof%> when %<operator[]%> is overloaded");
6146 return error_mark_node;
6147
6148 case INTEGER_CST:
6149 gcc_assert (integer_zerop (expr));
6150 return size_zero_node;
6151
6152 case NOP_EXPR:
6153 case INDIRECT_REF:
6154 base = fold_offsetof_1 (TREE_OPERAND (expr, 0), stop_ref);
6155 gcc_assert (base == error_mark_node || base == size_zero_node);
6156 return base;
6157
6158 case COMPONENT_REF:
6159 base = fold_offsetof_1 (TREE_OPERAND (expr, 0), stop_ref);
6160 if (base == error_mark_node)
6161 return base;
6162
6163 t = TREE_OPERAND (expr, 1);
6164 if (DECL_C_BIT_FIELD (t))
6165 {
6166 error ("attempt to take address of bit-field structure "
6167 "member %qD", t);
6168 return error_mark_node;
6169 }
6170 off = size_binop (PLUS_EXPR, DECL_FIELD_OFFSET (t),
6171 size_int (tree_low_cst (DECL_FIELD_BIT_OFFSET (t), 1)
6172 / BITS_PER_UNIT));
6173 break;
6174
6175 case ARRAY_REF:
6176 base = fold_offsetof_1 (TREE_OPERAND (expr, 0), stop_ref);
6177 if (base == error_mark_node)
6178 return base;
6179
6180 t = TREE_OPERAND (expr, 1);
6181 if (TREE_CODE (t) == INTEGER_CST && tree_int_cst_sgn (t) < 0)
6182 {
6183 code = MINUS_EXPR;
6184 t = fold_build1 (NEGATE_EXPR, TREE_TYPE (t), t);
6185 }
6186 t = convert (sizetype, t);
6187 off = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (TREE_TYPE (expr)), t);
6188 break;
6189
6190 case COMPOUND_EXPR:
6191 /* Handle static members of volatile structs. */
6192 t = TREE_OPERAND (expr, 1);
6193 gcc_assert (TREE_CODE (t) == VAR_DECL);
6194 return fold_offsetof_1 (t, stop_ref);
6195
6196 default:
6197 gcc_unreachable ();
6198 }
6199
6200 return size_binop (code, base, off);
6201}
6202
6203tree
6204fold_offsetof (tree expr, tree stop_ref)
6205{
6206 /* Convert back from the internal sizetype to size_t. */
6207 return convert (size_type_node, fold_offsetof_1 (expr, stop_ref));
6208}
6209
6210/* Print an error message for an invalid lvalue. USE says
6211 how the lvalue is being used and so selects the error message. */
6212
6213void
6214lvalue_error (enum lvalue_use use)
6215{
6216 switch (use)
6217 {
6218 case lv_assign:
6219 error ("lvalue required as left operand of assignment");
6220 break;
6221 case lv_increment:
6222 error ("lvalue required as increment operand");
6223 break;
6224 case lv_decrement:
6225 error ("lvalue required as decrement operand");
6226 break;
6227 case lv_addressof:
6228 error ("lvalue required as unary %<&%> operand");
6229 break;
6230 case lv_asm:
6231 error ("lvalue required in asm statement");
6232 break;
6233 default:
6234 gcc_unreachable ();
6235 }
6236}
6237
6238/* *PTYPE is an incomplete array. Complete it with a domain based on
6239 INITIAL_VALUE. If INITIAL_VALUE is not present, use 1 if DO_DEFAULT
6240 is true. Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
6241 2 if INITIAL_VALUE was NULL, and 3 if INITIAL_VALUE was empty. */
6242
6243int
6244complete_array_type (tree *ptype, tree initial_value, bool do_default)
6245{
6246 tree maxindex, type, main_type, elt, unqual_elt;
6247 int failure = 0, quals;
6248
6249 maxindex = size_zero_node;
6250 if (initial_value)
6251 {
6252 if (TREE_CODE (initial_value) == STRING_CST)
6253 {
6254 int eltsize
6255 = int_size_in_bytes (TREE_TYPE (TREE_TYPE (initial_value)));
6256 maxindex = size_int (TREE_STRING_LENGTH (initial_value)/eltsize - 1);
6257 }
6258 else if (TREE_CODE (initial_value) == CONSTRUCTOR)
6259 {
6260 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (initial_value);
6261
6262 if (VEC_empty (constructor_elt, v))
6263 {
6264 if (pedantic)
6265 failure = 3;
6266 maxindex = integer_minus_one_node;
6267 }
6268 else
6269 {
6270 tree curindex;
6271 unsigned HOST_WIDE_INT cnt;
6272 constructor_elt *ce;
6273
6274 if (VEC_index (constructor_elt, v, 0)->index)
6275 maxindex = fold_convert (sizetype,
6276 VEC_index (constructor_elt,
6277 v, 0)->index);
6278 curindex = maxindex;
6279
6280 for (cnt = 1;
6281 VEC_iterate (constructor_elt, v, cnt, ce);
6282 cnt++)
6283 {
6284 if (ce->index)
6285 curindex = fold_convert (sizetype, ce->index);
6286 else
6287 curindex = size_binop (PLUS_EXPR, curindex, size_one_node);
6288
6289 if (tree_int_cst_lt (maxindex, curindex))
6290 maxindex = curindex;
6291 }
6292 }
6293 }
6294 else
6295 {
6296 /* Make an error message unless that happened already. */
6297 if (initial_value != error_mark_node)
6298 failure = 1;
6299 }
6300 }
6301 else
6302 {
6303 failure = 2;
6304 if (!do_default)
6305 return failure;
6306 }
6307
6308 type = *ptype;
6309 elt = TREE_TYPE (type);
6310 quals = TYPE_QUALS (strip_array_types (elt));
6311 if (quals == 0)
6312 unqual_elt = elt;
6313 else
6314 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
6315
6316 /* Using build_distinct_type_copy and modifying things afterward instead
6317 of using build_array_type to create a new type preserves all of the
6318 TYPE_LANG_FLAG_? bits that the front end may have set. */
6319 main_type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
6320 TREE_TYPE (main_type) = unqual_elt;
6321 TYPE_DOMAIN (main_type) = build_index_type (maxindex);
6322 layout_type (main_type);
6323
6324 if (quals == 0)
6325 type = main_type;
6326 else
6327 type = c_build_qualified_type (main_type, quals);
6328
6329 *ptype = type;
6330 return failure;
6331}
6332
6333
6334/* Used to help initialize the builtin-types.def table. When a type of
6335 the correct size doesn't exist, use error_mark_node instead of NULL.
6336 The later results in segfaults even when a decl using the type doesn't
6337 get invoked. */
6338
6339tree
6340builtin_type_for_size (int size, bool unsignedp)
6341{
6342 tree type = lang_hooks.types.type_for_size (size, unsignedp);
6343 return type ? type : error_mark_node;
6344}
6345
6346/* A helper function for resolve_overloaded_builtin in resolving the
6347 overloaded __sync_ builtins. Returns a positive power of 2 if the
6348 first operand of PARAMS is a pointer to a supported data type.
6349 Returns 0 if an error is encountered. */
6350
6351static int
6352sync_resolve_size (tree function, tree params)
6353{
6354 tree type;
6355 int size;
6356
6357 if (params == NULL)
6358 {
6359 error ("too few arguments to function %qE", function);
6360 return 0;
6361 }
6362
6363 type = TREE_TYPE (TREE_VALUE (params));
6364 if (TREE_CODE (type) != POINTER_TYPE)
6365 goto incompatible;
6366
6367 type = TREE_TYPE (type);
6368 if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
6369 goto incompatible;
6370
6371 size = tree_low_cst (TYPE_SIZE_UNIT (type), 1);
6372 if (size == 1 || size == 2 || size == 4 || size == 8 || size == 16)
6373 return size;
6374
6375 incompatible:
6376 error ("incompatible type for argument %d of %qE", 1, function);
6377 return 0;
6378}
6379
6380/* A helper function for resolve_overloaded_builtin. Adds casts to
6381 PARAMS to make arguments match up with those of FUNCTION. Drops
6382 the variadic arguments at the end. Returns false if some error
6383 was encountered; true on success. */
6384
6385static bool
6386sync_resolve_params (tree orig_function, tree function, tree params)
6387{
6388 tree arg_types = TYPE_ARG_TYPES (TREE_TYPE (function));
6389 tree ptype;
6390 int number;
6391
6392 /* We've declared the implementation functions to use "volatile void *"
6393 as the pointer parameter, so we shouldn't get any complaints from the
6394 call to check_function_arguments what ever type the user used. */
6395 arg_types = TREE_CHAIN (arg_types);
6396 ptype = TREE_TYPE (TREE_TYPE (TREE_VALUE (params)));
6397 number = 2;
6398
6399 /* For the rest of the values, we need to cast these to FTYPE, so that we
6400 don't get warnings for passing pointer types, etc. */
6401 while (arg_types != void_list_node)
6402 {
6403 tree val;
6404
6405 params = TREE_CHAIN (params);
6406 if (params == NULL)
6407 {
6408 error ("too few arguments to function %qE", orig_function);
6409 return false;
6410 }
6411
6412 /* ??? Ideally for the first conversion we'd use convert_for_assignment
6413 so that we get warnings for anything that doesn't match the pointer
6414 type. This isn't portable across the C and C++ front ends atm. */
6415 val = TREE_VALUE (params);
6416 val = convert (ptype, val);
6417 val = convert (TREE_VALUE (arg_types), val);
6418 TREE_VALUE (params) = val;
6419
6420 arg_types = TREE_CHAIN (arg_types);
6421 number++;
6422 }
6423
6424 /* The definition of these primitives is variadic, with the remaining
6425 being "an optional list of variables protected by the memory barrier".
6426 No clue what that's supposed to mean, precisely, but we consider all
6427 call-clobbered variables to be protected so we're safe. */
6428 TREE_CHAIN (params) = NULL;
6429
6430 return true;
6431}
6432
6433/* A helper function for resolve_overloaded_builtin. Adds a cast to
6434 RESULT to make it match the type of the first pointer argument in
6435 PARAMS. */
6436
6437static tree
6438sync_resolve_return (tree params, tree result)
6439{
6440 tree ptype = TREE_TYPE (TREE_TYPE (TREE_VALUE (params)));
6441 ptype = TYPE_MAIN_VARIANT (ptype);
6442 return convert (ptype, result);
6443}
6444
6445/* Some builtin functions are placeholders for other expressions. This
6446 function should be called immediately after parsing the call expression
6447 before surrounding code has committed to the type of the expression.
6448
6449 FUNCTION is the DECL that has been invoked; it is known to be a builtin.
6450 PARAMS is the argument list for the call. The return value is non-null
6451 when expansion is complete, and null if normal processing should
6452 continue. */
6453
6454tree
6455resolve_overloaded_builtin (tree function, tree params)
6456{
6457 enum built_in_function orig_code = DECL_FUNCTION_CODE (function);
6458 switch (DECL_BUILT_IN_CLASS (function))
6459 {
6460 case BUILT_IN_NORMAL:
6461 break;
6462 case BUILT_IN_MD:
6463 if (targetm.resolve_overloaded_builtin)
6464 return targetm.resolve_overloaded_builtin (function, params);
6465 else
6466 return NULL_TREE;
6467 default:
6468 return NULL_TREE;
6469 }
6470
6471 /* Handle BUILT_IN_NORMAL here. */
6472 switch (orig_code)
6473 {
6474 case BUILT_IN_FETCH_AND_ADD_N:
6475 case BUILT_IN_FETCH_AND_SUB_N:
6476 case BUILT_IN_FETCH_AND_OR_N:
6477 case BUILT_IN_FETCH_AND_AND_N:
6478 case BUILT_IN_FETCH_AND_XOR_N:
6479 case BUILT_IN_FETCH_AND_NAND_N:
6480 case BUILT_IN_ADD_AND_FETCH_N:
6481 case BUILT_IN_SUB_AND_FETCH_N:
6482 case BUILT_IN_OR_AND_FETCH_N:
6483 case BUILT_IN_AND_AND_FETCH_N:
6484 case BUILT_IN_XOR_AND_FETCH_N:
6485 case BUILT_IN_NAND_AND_FETCH_N:
6486 case BUILT_IN_BOOL_COMPARE_AND_SWAP_N:
6487 case BUILT_IN_VAL_COMPARE_AND_SWAP_N:
6488 case BUILT_IN_LOCK_TEST_AND_SET_N:
6489 case BUILT_IN_LOCK_RELEASE_N:
6490 {
6491 int n = sync_resolve_size (function, params);
6492 tree new_function, result;
6493
6494 if (n == 0)
6495 return error_mark_node;
6496
6497 new_function = built_in_decls[orig_code + exact_log2 (n) + 1];
6498 if (!sync_resolve_params (function, new_function, params))
6499 return error_mark_node;
6500
6501 result = build_function_call (new_function, params);
6502 if (orig_code != BUILT_IN_BOOL_COMPARE_AND_SWAP_N
6503 && orig_code != BUILT_IN_LOCK_RELEASE_N)
6504 result = sync_resolve_return (params, result);
6505
6506 return result;
6507 }
6508
6509 default:
6510 return NULL_TREE;
6511 }
6512}
6513
6514/* Ignoring their sign, return true if two scalar types are the same. */
6515bool
6516same_scalar_type_ignoring_signedness (tree t1, tree t2)
6517{
6518 enum tree_code c1 = TREE_CODE (t1), c2 = TREE_CODE (t2);
6519
6520 gcc_assert ((c1 == INTEGER_TYPE || c1 == REAL_TYPE)
6521 && (c2 == INTEGER_TYPE || c2 == REAL_TYPE));
6522
6523 /* Equality works here because c_common_signed_type uses
6524 TYPE_MAIN_VARIANT. */
6525 return lang_hooks.types.signed_type (t1)
6526 == lang_hooks.types.signed_type (t2);
6527}
6528
6529/* Check for missing format attributes on function pointers. LTYPE is
6530 the new type or left-hand side type. RTYPE is the old type or
6531 right-hand side type. Returns TRUE if LTYPE is missing the desired
6532 attribute. */
6533
6534bool
6535check_missing_format_attribute (tree ltype, tree rtype)
6536{
6537 tree const ttr = TREE_TYPE (rtype), ttl = TREE_TYPE (ltype);
6538 tree ra;
6539
6540 for (ra = TYPE_ATTRIBUTES (ttr); ra; ra = TREE_CHAIN (ra))
6541 if (is_attribute_p ("format", TREE_PURPOSE (ra)))
6542 break;
6543 if (ra)
6544 {
6545 tree la;
6546 for (la = TYPE_ATTRIBUTES (ttl); la; la = TREE_CHAIN (la))
6547 if (is_attribute_p ("format", TREE_PURPOSE (la)))
6548 break;
6549 return !la;
6550 }
6551 else
6552 return false;
6553}
6554
6555/* Subscripting with type char is likely to lose on a machine where
6556 chars are signed. So warn on any machine, but optionally. Don't
6557 warn for unsigned char since that type is safe. Don't warn for
6558 signed char because anyone who uses that must have done so
6559 deliberately. Furthermore, we reduce the false positive load by
6560 warning only for non-constant value of type char. */
6561
6562void
6563warn_array_subscript_with_type_char (tree index)
6564{
6565 if (TYPE_MAIN_VARIANT (TREE_TYPE (index)) == char_type_node
6566 && TREE_CODE (index) != INTEGER_CST)
6567 warning (OPT_Wchar_subscripts, "array subscript has type %<char%>");
6568}
6569
6570/* Implement -Wparentheses for the unexpected C precedence rules, to
6571 cover cases like x + y << z which readers are likely to
6572 misinterpret. We have seen an expression in which CODE is a binary
6573 operator used to combine expressions headed by CODE_LEFT and
6574 CODE_RIGHT. CODE_LEFT and CODE_RIGHT may be ERROR_MARK, which
6575 means that that side of the expression was not formed using a
6576 binary operator, or it was enclosed in parentheses. */
6577
6578void
6579warn_about_parentheses (enum tree_code code, enum tree_code code_left,
6580 enum tree_code code_right)
6581{
6582 if (!warn_parentheses)
6583 return;
6584
6585 if (code == LSHIFT_EXPR || code == RSHIFT_EXPR)
6586 {
6587 if (code_left == PLUS_EXPR || code_left == MINUS_EXPR
6588 || code_right == PLUS_EXPR || code_right == MINUS_EXPR)
6589 warning (OPT_Wparentheses,
6590 "suggest parentheses around + or - inside shift");
6591 }
6592
6593 if (code == TRUTH_ORIF_EXPR)
6594 {
6595 if (code_left == TRUTH_ANDIF_EXPR
6596 || code_right == TRUTH_ANDIF_EXPR)
6597 warning (OPT_Wparentheses,
6598 "suggest parentheses around && within ||");
6599 }
6600
6601 if (code == BIT_IOR_EXPR)
6602 {
6603 if (code_left == BIT_AND_EXPR || code_left == BIT_XOR_EXPR
6604 || code_left == PLUS_EXPR || code_left == MINUS_EXPR
6605 || code_right == BIT_AND_EXPR || code_right == BIT_XOR_EXPR
6606 || code_right == PLUS_EXPR || code_right == MINUS_EXPR)
6607 warning (OPT_Wparentheses,
6608 "suggest parentheses around arithmetic in operand of |");
6609 /* Check cases like x|y==z */
6610 if (TREE_CODE_CLASS (code_left) == tcc_comparison
6611 || TREE_CODE_CLASS (code_right) == tcc_comparison)
6612 warning (OPT_Wparentheses,
6613 "suggest parentheses around comparison in operand of |");
6614 }
6615
6616 if (code == BIT_XOR_EXPR)
6617 {
6618 if (code_left == BIT_AND_EXPR
6619 || code_left == PLUS_EXPR || code_left == MINUS_EXPR
6620 || code_right == BIT_AND_EXPR
6621 || code_right == PLUS_EXPR || code_right == MINUS_EXPR)
6622 warning (OPT_Wparentheses,
6623 "suggest parentheses around arithmetic in operand of ^");
6624 /* Check cases like x^y==z */
6625 if (TREE_CODE_CLASS (code_left) == tcc_comparison
6626 || TREE_CODE_CLASS (code_right) == tcc_comparison)
6627 warning (OPT_Wparentheses,
6628 "suggest parentheses around comparison in operand of ^");
6629 }
6630
6631 if (code == BIT_AND_EXPR)
6632 {
6633 if (code_left == PLUS_EXPR || code_left == MINUS_EXPR
6634 || code_right == PLUS_EXPR || code_right == MINUS_EXPR)
6635 warning (OPT_Wparentheses,
6636 "suggest parentheses around + or - in operand of &");
6637 /* Check cases like x&y==z */
6638 if (TREE_CODE_CLASS (code_left) == tcc_comparison
6639 || TREE_CODE_CLASS (code_right) == tcc_comparison)
6640 warning (OPT_Wparentheses,
6641 "suggest parentheses around comparison in operand of &");
6642 }
6643
6644 /* Similarly, check for cases like 1<=i<=10 that are probably errors. */
6645 if (TREE_CODE_CLASS (code) == tcc_comparison
6646 && (TREE_CODE_CLASS (code_left) == tcc_comparison
6647 || TREE_CODE_CLASS (code_right) == tcc_comparison))
6648 warning (OPT_Wparentheses, "comparisons like X<=Y<=Z do not "
6649 "have their mathematical meaning");
6650}
6651
6652
6653#include "gt-c-common.h"