c-decl.c revision 96549
1/* Process declarations and variables for C compiler.
2   Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3   2001, 2002 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, 59 Temple Place - Suite 330, Boston, MA
2002111-1307, USA.  */
21
22/* $FreeBSD: head/contrib/gcc/c-decl.c 96549 2002-05-14 00:30:25Z obrien $ */
23
24/* Process declarations and symbol lookup for C front end.
25   Also constructs types; the standard scalar types at initialization,
26   and structure, union, array and enum types when they are declared.  */
27
28/* ??? not all decl nodes are given the most useful possible
29   line numbers.  For example, the CONST_DECLs for enum values.  */
30
31#include "config.h"
32#include "system.h"
33#include "intl.h"
34#include "tree.h"
35#include "tree-inline.h"
36#include "rtl.h"
37#include "flags.h"
38#include "function.h"
39#include "output.h"
40#include "expr.h"
41#include "c-tree.h"
42#include "c-lex.h"
43#include "toplev.h"
44#include "ggc.h"
45#include "tm_p.h"
46#include "cpplib.h"
47#include "target.h"
48#include "debug.h"
49#include "timevar.h"
50#include "c-common.h"
51#include "c-pragma.h"
52
53/* In grokdeclarator, distinguish syntactic contexts of declarators.  */
54enum decl_context
55{ NORMAL,			/* Ordinary declaration */
56  FUNCDEF,			/* Function definition */
57  PARM,				/* Declaration of parm before function body */
58  FIELD,			/* Declaration inside struct or union */
59  BITFIELD,			/* Likewise but with specified width */
60  TYPENAME};			/* Typename (inside cast or sizeof)  */
61
62
63/* Nonzero if we have seen an invalid cross reference
64   to a struct, union, or enum, but not yet printed the message.  */
65
66tree pending_invalid_xref;
67/* File and line to appear in the eventual error message.  */
68const char *pending_invalid_xref_file;
69int pending_invalid_xref_line;
70
71/* While defining an enum type, this is 1 plus the last enumerator
72   constant value.  Note that will do not have to save this or `enum_overflow'
73   around nested function definition since such a definition could only
74   occur in an enum value expression and we don't use these variables in
75   that case.  */
76
77static tree enum_next_value;
78
79/* Nonzero means that there was overflow computing enum_next_value.  */
80
81static int enum_overflow;
82
83/* Parsing a function declarator leaves a list of parameter names
84   or a chain or parameter decls here.  */
85
86static tree last_function_parms;
87
88/* Parsing a function declarator leaves here a chain of structure
89   and enum types declared in the parmlist.  */
90
91static tree last_function_parm_tags;
92
93/* After parsing the declarator that starts a function definition,
94   `start_function' puts here the list of parameter names or chain of decls.
95   `store_parm_decls' finds it here.  */
96
97static tree current_function_parms;
98
99/* Similar, for last_function_parm_tags.  */
100static tree current_function_parm_tags;
101
102/* Similar, for the file and line that the prototype came from if this is
103   an old-style definition.  */
104static const char *current_function_prototype_file;
105static int current_function_prototype_line;
106
107/* The current statement tree.  */
108
109static struct stmt_tree_s c_stmt_tree;
110
111/* The current scope statement stack.  */
112
113static tree c_scope_stmt_stack;
114
115/* A list (chain of TREE_LIST nodes) of all LABEL_DECLs in the function
116   that have names.  Here so we can clear out their names' definitions
117   at the end of the function.  */
118
119static tree named_labels;
120
121/* A list of LABEL_DECLs from outer contexts that are currently shadowed.  */
122
123static tree shadowed_labels;
124
125/* Nonzero when store_parm_decls is called indicates a varargs function.
126   Value not meaningful after store_parm_decls.  */
127
128static int c_function_varargs;
129
130/* Set to 0 at beginning of a function definition, set to 1 if
131   a return statement that specifies a return value is seen.  */
132
133int current_function_returns_value;
134
135/* Set to 0 at beginning of a function definition, set to 1 if
136   a return statement with no argument is seen.  */
137
138int current_function_returns_null;
139
140/* Set to 0 at beginning of a function definition, set to 1 if
141   a call to a noreturn function is seen.  */
142
143int current_function_returns_abnormally;
144
145/* Set to nonzero by `grokdeclarator' for a function
146   whose return type is defaulted, if warnings for this are desired.  */
147
148static int warn_about_return_type;
149
150/* Nonzero when starting a function declared `extern inline'.  */
151
152static int current_extern_inline;
153
154/* For each binding contour we allocate a binding_level structure
155 * which records the names defined in that contour.
156 * Contours include:
157 *  0) the global one
158 *  1) one for each function definition,
159 *     where internal declarations of the parameters appear.
160 *  2) one for each compound statement,
161 *     to record its declarations.
162 *
163 * The current meaning of a name can be found by searching the levels from
164 * the current one out to the global one.
165 */
166
167/* Note that the information in the `names' component of the global contour
168   is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers.  */
169
170struct binding_level
171  {
172    /* A chain of _DECL nodes for all variables, constants, functions,
173       and typedef types.  These are in the reverse of the order supplied.
174     */
175    tree names;
176
177    /* A list of structure, union and enum definitions,
178     * for looking up tag names.
179     * It is a chain of TREE_LIST nodes, each of whose TREE_PURPOSE is a name,
180     * or NULL_TREE; and whose TREE_VALUE is a RECORD_TYPE, UNION_TYPE,
181     * or ENUMERAL_TYPE node.
182     */
183    tree tags;
184
185    /* For each level, a list of shadowed outer-level local definitions
186       to be restored when this level is popped.
187       Each link is a TREE_LIST whose TREE_PURPOSE is an identifier and
188       whose TREE_VALUE is its old definition (a kind of ..._DECL node).  */
189    tree shadowed;
190
191    /* For each level (except not the global one),
192       a chain of BLOCK nodes for all the levels
193       that were entered and exited one level down.  */
194    tree blocks;
195
196    /* The BLOCK node for this level, if one has been preallocated.
197       If 0, the BLOCK is allocated (if needed) when the level is popped.  */
198    tree this_block;
199
200    /* The binding level which this one is contained in (inherits from).  */
201    struct binding_level *level_chain;
202
203    /* Nonzero for the level that holds the parameters of a function.  */
204    char parm_flag;
205
206    /* Nonzero if this level "doesn't exist" for tags.  */
207    char tag_transparent;
208
209    /* Nonzero if sublevels of this level "don't exist" for tags.
210       This is set in the parm level of a function definition
211       while reading the function body, so that the outermost block
212       of the function body will be tag-transparent.  */
213    char subblocks_tag_transparent;
214
215    /* Nonzero means make a BLOCK for this level regardless of all else.  */
216    char keep;
217
218    /* Nonzero means make a BLOCK if this level has any subblocks.  */
219    char keep_if_subblocks;
220
221    /* Number of decls in `names' that have incomplete
222       structure or union types.  */
223    int n_incomplete;
224
225    /* A list of decls giving the (reversed) specified order of parms,
226       not including any forward-decls in the parmlist.
227       This is so we can put the parms in proper order for assign_parms.  */
228    tree parm_order;
229  };
230
231#define NULL_BINDING_LEVEL (struct binding_level *) NULL
232
233/* The binding level currently in effect.  */
234
235static struct binding_level *current_binding_level;
236
237/* A chain of binding_level structures awaiting reuse.  */
238
239static struct binding_level *free_binding_level;
240
241/* The outermost binding level, for names of file scope.
242   This is created when the compiler is started and exists
243   through the entire run.  */
244
245static struct binding_level *global_binding_level;
246
247/* Binding level structures are initialized by copying this one.  */
248
249static struct binding_level clear_binding_level
250  = {NULL, NULL, NULL, NULL, NULL, NULL_BINDING_LEVEL, 0, 0, 0, 0, 0, 0,
251     NULL};
252
253/* Nonzero means unconditionally make a BLOCK for the next level pushed.  */
254
255static int keep_next_level_flag;
256
257/* Nonzero means make a BLOCK for the next level pushed
258   if it has subblocks.  */
259
260static int keep_next_if_subblocks;
261
262/* The chain of outer levels of label scopes.
263   This uses the same data structure used for binding levels,
264   but it works differently: each link in the chain records
265   saved values of named_labels and shadowed_labels for
266   a label binding level outside the current one.  */
267
268static struct binding_level *label_level_chain;
269
270/* Functions called automatically at the beginning and end of execution.  */
271
272tree static_ctors, static_dtors;
273
274/* Forward declarations.  */
275
276static struct binding_level * make_binding_level	PARAMS ((void));
277static void mark_binding_level		PARAMS ((void *));
278static void clear_limbo_values		PARAMS ((tree));
279static int duplicate_decls		PARAMS ((tree, tree, int));
280static int redeclaration_error_message	PARAMS ((tree, tree));
281static void storedecls			PARAMS ((tree));
282static void storetags			PARAMS ((tree));
283static tree lookup_tag			PARAMS ((enum tree_code, tree,
284						 struct binding_level *, int));
285static tree lookup_tag_reverse		PARAMS ((tree));
286static tree grokdeclarator		PARAMS ((tree, tree, enum decl_context,
287						 int));
288static tree grokparms			PARAMS ((tree, int));
289static void layout_array_type		PARAMS ((tree));
290static tree c_make_fname_decl           PARAMS ((tree, int));
291static void c_expand_body               PARAMS ((tree, int, int));
292static void warn_if_shadowing		PARAMS ((tree, tree));
293
294/* C-specific option variables.  */
295
296/* Nonzero means allow type mismatches in conditional expressions;
297   just make their values `void'.  */
298
299int flag_cond_mismatch;
300
301/* Nonzero means don't recognize the keyword `asm'.  */
302
303int flag_no_asm;
304
305/* Nonzero means do some things the same way PCC does.  */
306
307int flag_traditional;
308
309/* Nonzero means enable C89 Amendment 1 features.  */
310
311int flag_isoc94 = 0;
312
313/* Nonzero means use the ISO C99 dialect of C.  */
314
315int flag_isoc99 = 0;
316
317/* Nonzero means allow the BSD kernel printf enhancments.  */
318
319int flag_bsd_format = 0;
320
321/* Nonzero means that we have builtin functions, and main is an int */
322
323int flag_hosted = 1;
324
325/* Nonzero means add default format_arg attributes for functions not
326   in ISO C.  */
327
328int flag_noniso_default_format_attributes = 1;
329
330/* Nonzero means to allow single precision math even if we're generally
331   being traditional.  */
332int flag_allow_single_precision = 0;
333
334/* Nonzero means to treat bitfields as signed unless they say `unsigned'.  */
335
336int flag_signed_bitfields = 1;
337int explicit_flag_signed_bitfields = 0;
338
339/* Nonzero means warn about use of implicit int.  */
340
341int warn_implicit_int;
342
343/* Nonzero means warn about usage of long long when `-pedantic'.  */
344
345int warn_long_long = 1;
346
347/* Nonzero means message about use of implicit function declarations;
348 1 means warning; 2 means error.  */
349
350int mesg_implicit_function_declaration = -1;
351
352/* Nonzero means give string constants the type `const char *'
353   to get extra warnings from them.  These warnings will be too numerous
354   to be useful, except in thoroughly ANSIfied programs.  */
355
356int flag_const_strings;
357
358/* Nonzero means warn about pointer casts that can drop a type qualifier
359   from the pointer target type.  */
360
361int warn_cast_qual;
362
363/* Nonzero means warn when casting a function call to a type that does
364   not match the return type (e.g. (float)sqrt() or (anything*)malloc()
365   when there is no previous declaration of sqrt or malloc.  */
366
367int warn_bad_function_cast;
368
369/* Warn about functions which might be candidates for format attributes.  */
370
371int warn_missing_format_attribute;
372
373/* Warn about traditional constructs whose meanings changed in ANSI C.  */
374
375int warn_traditional;
376
377/* Nonzero means warn about sizeof(function) or addition/subtraction
378   of function pointers.  */
379
380int warn_pointer_arith;
381
382/* Nonzero means warn for non-prototype function decls
383   or non-prototyped defs without previous prototype.  */
384
385int warn_strict_prototypes;
386
387/* Nonzero means warn for any global function def
388   without separate previous prototype decl.  */
389
390int warn_missing_prototypes;
391
392/* Nonzero means warn for any global function def
393   without separate previous decl.  */
394
395int warn_missing_declarations;
396
397/* Nonzero means warn about multiple (redundant) decls for the same single
398   variable or function.  */
399
400int warn_redundant_decls = 0;
401
402/* Nonzero means warn about extern declarations of objects not at
403   file-scope level and about *all* declarations of functions (whether
404   extern or static) not at file-scope level.  Note that we exclude
405   implicit function declarations.  To get warnings about those, use
406   -Wimplicit.  */
407
408int warn_nested_externs = 0;
409
410/* Warn about a subscript that has type char.  */
411
412int warn_char_subscripts = 0;
413
414/* Warn if a type conversion is done that might have confusing results.  */
415
416int warn_conversion;
417
418/* Warn if adding () is suggested.  */
419
420int warn_parentheses;
421
422/* Warn if initializer is not completely bracketed.  */
423
424int warn_missing_braces;
425
426/* Warn if main is suspicious.  */
427
428int warn_main;
429
430/* Warn about #pragma directives that are not recognised.  */
431
432int warn_unknown_pragmas = 0; /* Tri state variable.  */
433
434/* Warn about comparison of signed and unsigned values.
435   If -1, neither -Wsign-compare nor -Wno-sign-compare has been specified.  */
436
437int warn_sign_compare = -1;
438
439/* Warn about testing equality of floating point numbers.  */
440
441int warn_float_equal = 0;
442
443/* Nonzero means warn about use of multicharacter literals.  */
444
445int warn_multichar = 1;
446
447/* Nonzero means `$' can be in an identifier.  */
448
449#ifndef DOLLARS_IN_IDENTIFIERS
450#define DOLLARS_IN_IDENTIFIERS 1
451#endif
452int dollars_in_ident = DOLLARS_IN_IDENTIFIERS;
453
454/* States indicating how grokdeclarator() should handle declspecs marked
455   with __attribute__((deprecated)).  An object declared as
456   __attribute__((deprecated)) suppresses warnings of uses of other
457   deprecated items.  */
458
459enum deprecated_states {
460  DEPRECATED_NORMAL,
461  DEPRECATED_SUPPRESS
462};
463
464static enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
465
466/* Decode the string P as a language-specific option for C.
467   Return the number of strings consumed.  Should not complain
468   if it does not recognise the option.  */
469
470int
471c_decode_option (argc, argv)
472     int argc ATTRIBUTE_UNUSED;
473     char **argv;
474{
475  int strings_processed;
476  char *p = argv[0];
477
478  strings_processed = cpp_handle_option (parse_in, argc, argv, 0);
479
480  if (!strcmp (p, "-ftraditional") || !strcmp (p, "-traditional"))
481    {
482      warning ("-traditional is deprecated and may be removed");
483      flag_traditional = 1;
484      flag_writable_strings = 1;
485    }
486  else if (!strcmp (p, "-fallow-single-precision"))
487    flag_allow_single_precision = 1;
488  else if (!strcmp (p, "-fhosted") || !strcmp (p, "-fno-freestanding"))
489    {
490      flag_hosted = 1;
491      flag_no_builtin = 0;
492    }
493  else if (!strcmp (p, "-ffreestanding") || !strcmp (p, "-fno-hosted"))
494    {
495      flag_hosted = 0;
496      flag_no_builtin = 1;
497      /* warn_main will be 2 if set by -Wall, 1 if set by -Wmain */
498      if (warn_main == 2)
499	warn_main = 0;
500    }
501  else if (!strcmp (p, "-fnotraditional") || !strcmp (p, "-fno-traditional"))
502    {
503      flag_traditional = 0;
504      flag_writable_strings = 0;
505    }
506  else if (!strncmp (p, "-std=", 5))
507    {
508      /* Select the appropriate language standard.  We currently
509	 recognize:
510	 -std=iso9899:1990	same as -ansi
511	 -std=iso9899:199409	ISO C as modified in amend. 1
512	 -std=iso9899:1999	ISO C 99
513	 -std=c89		same as -std=iso9899:1990
514	 -std=c99		same as -std=iso9899:1999
515	 -std=gnu89		default, iso9899:1990 + gnu extensions
516	 -std=gnu99		iso9899:1999 + gnu extensions
517	 -std=bsd		iso9899:1999 + BSD kernel printf extensions
518      */
519      const char *const argstart = &p[5];
520
521      if (!strcmp (argstart, "iso9899:1990")
522	  || !strcmp (argstart, "c89"))
523	{
524	iso_1990:
525	  flag_isoc94 = 0;
526	iso_1994:
527	  flag_traditional = 0;
528	  flag_writable_strings = 0;
529	  flag_no_asm = 1;
530	  flag_no_nonansi_builtin = 1;
531	  flag_noniso_default_format_attributes = 0;
532	  flag_isoc99 = 0;
533	  flag_bsd_format = 0;
534	}
535      else if (!strcmp (argstart, "iso9899:199409"))
536	{
537	  flag_isoc94 = 1;
538	  goto iso_1994;
539	}
540      else if (!strcmp (argstart, "iso9899:199x")
541	       || !strcmp (argstart, "iso9899:1999")
542	       || !strcmp (argstart, "c9x")
543	       || !strcmp (argstart, "c99"))
544	{
545	  flag_traditional = 0;
546	  flag_writable_strings = 0;
547	  flag_no_asm = 1;
548	  flag_no_nonansi_builtin = 1;
549	  flag_noniso_default_format_attributes = 0;
550	  flag_isoc99 = 1;
551	  flag_isoc94 = 1;
552	  flag_bsd_format = 0;
553	}
554      else if (!strcmp (argstart, "gnu89"))
555	{
556	  flag_traditional = 0;
557	  flag_writable_strings = 0;
558	  flag_no_asm = 0;
559	  flag_no_nonansi_builtin = 0;
560	  flag_noniso_default_format_attributes = 1;
561	  flag_isoc99 = 0;
562	  flag_isoc94 = 0;
563	  flag_bsd_format = 0;
564	}
565      else if (!strcmp (argstart, "gnu9x") || !strcmp (argstart, "gnu99"))
566	{
567	  flag_traditional = 0;
568	  flag_writable_strings = 0;
569	  flag_no_asm = 0;
570	  flag_no_nonansi_builtin = 0;
571	  flag_noniso_default_format_attributes = 1;
572	  flag_isoc99 = 1;
573	  flag_isoc94 = 1;
574	  flag_bsd_format = 0;
575	}
576      else if (!strcmp (argstart, "bsd"))
577	{
578	  flag_traditional = 0;
579	  flag_writable_strings = 0;
580	  flag_no_asm = 0;
581	  flag_no_nonansi_builtin = 0;
582	  flag_noniso_default_format_attributes = 1;
583	  flag_isoc99 = 0;
584	  flag_isoc94 = 0;
585	  flag_isoc94 = 0;
586	  flag_bsd_format = 1;
587	}
588      else
589	error ("unknown C standard `%s'", argstart);
590    }
591  else if (!strcmp (p, "-fdollars-in-identifiers"))
592    dollars_in_ident = 1;
593  else if (!strcmp (p, "-fno-dollars-in-identifiers"))
594    dollars_in_ident = 0;
595  else if (!strcmp (p, "-fsigned-char"))
596    flag_signed_char = 1;
597  else if (!strcmp (p, "-funsigned-char"))
598    flag_signed_char = 0;
599  else if (!strcmp (p, "-fno-signed-char"))
600    flag_signed_char = 0;
601  else if (!strcmp (p, "-fno-unsigned-char"))
602    flag_signed_char = 1;
603  else if (!strcmp (p, "-fsigned-bitfields")
604	   || !strcmp (p, "-fno-unsigned-bitfields"))
605    {
606      flag_signed_bitfields = 1;
607      explicit_flag_signed_bitfields = 1;
608    }
609  else if (!strcmp (p, "-funsigned-bitfields")
610	   || !strcmp (p, "-fno-signed-bitfields"))
611    {
612      flag_signed_bitfields = 0;
613      explicit_flag_signed_bitfields = 1;
614    }
615  else if (!strcmp (p, "-fshort-enums"))
616    flag_short_enums = 1;
617  else if (!strcmp (p, "-fno-short-enums"))
618    flag_short_enums = 0;
619  else if (!strcmp (p, "-fshort-wchar"))
620    flag_short_wchar = 1;
621  else if (!strcmp (p, "-fno-short-wchar"))
622    flag_short_wchar = 0;
623  else if (!strcmp (p, "-fcond-mismatch"))
624    flag_cond_mismatch = 1;
625  else if (!strcmp (p, "-fno-cond-mismatch"))
626    flag_cond_mismatch = 0;
627  else if (!strcmp (p, "-fshort-double"))
628    flag_short_double = 1;
629  else if (!strcmp (p, "-fno-short-double"))
630    flag_short_double = 0;
631  else if (!strcmp (p, "-fasm"))
632    flag_no_asm = 0;
633  else if (!strcmp (p, "-fno-asm"))
634    flag_no_asm = 1;
635  else if (!strcmp (p, "-fbuiltin"))
636    flag_no_builtin = 0;
637  else if (!strcmp (p, "-fno-builtin"))
638    flag_no_builtin = 1;
639  else if (!strncmp (p, "-fno-builtin-", strlen ("-fno-builtin-")))
640    disable_builtin_function (p + strlen ("-fno-builtin-"));
641  else if (p[0] == '-' && p[1] == 'f' && dump_switch_p (p + 2))
642    ;
643  else if (!strcmp (p, "-ansi"))
644    goto iso_1990;
645  else if (!strcmp (p, "-Werror-implicit-function-declaration"))
646    mesg_implicit_function_declaration = 2;
647  else if (!strcmp (p, "-Wimplicit-function-declaration"))
648    mesg_implicit_function_declaration = 1;
649  else if (!strcmp (p, "-Wno-implicit-function-declaration"))
650    mesg_implicit_function_declaration = 0;
651  else if (!strcmp (p, "-Wimplicit-int"))
652    warn_implicit_int = 1;
653  else if (!strcmp (p, "-Wno-implicit-int"))
654    warn_implicit_int = 0;
655  else if (!strcmp (p, "-Wimplicit"))
656    {
657      warn_implicit_int = 1;
658      if (mesg_implicit_function_declaration != 2)
659	mesg_implicit_function_declaration = 1;
660    }
661  else if (!strcmp (p, "-Wno-implicit"))
662    warn_implicit_int = 0, mesg_implicit_function_declaration = 0;
663  else if (!strcmp (p, "-Wlong-long"))
664    warn_long_long = 1;
665  else if (!strcmp (p, "-Wno-long-long"))
666    warn_long_long = 0;
667  else if (!strcmp (p, "-Wwrite-strings"))
668    flag_const_strings = 1;
669  else if (!strcmp (p, "-Wno-write-strings"))
670    flag_const_strings = 0;
671  else if (!strcmp (p, "-Wcast-qual"))
672    warn_cast_qual = 1;
673  else if (!strcmp (p, "-Wno-cast-qual"))
674    warn_cast_qual = 0;
675  else if (!strcmp (p, "-Wbad-function-cast"))
676    warn_bad_function_cast = 1;
677  else if (!strcmp (p, "-Wno-bad-function-cast"))
678    warn_bad_function_cast = 0;
679  else if (!strcmp (p, "-Wno-missing-noreturn"))
680    warn_missing_noreturn = 0;
681  else if (!strcmp (p, "-Wmissing-format-attribute"))
682    warn_missing_format_attribute = 1;
683  else if (!strcmp (p, "-Wno-missing-format-attribute"))
684    warn_missing_format_attribute = 0;
685  else if (!strcmp (p, "-Wpointer-arith"))
686    warn_pointer_arith = 1;
687  else if (!strcmp (p, "-Wno-pointer-arith"))
688    warn_pointer_arith = 0;
689  else if (!strcmp (p, "-Wstrict-prototypes"))
690    warn_strict_prototypes = 1;
691  else if (!strcmp (p, "-Wno-strict-prototypes"))
692    warn_strict_prototypes = 0;
693  else if (!strcmp (p, "-Wmissing-prototypes"))
694    warn_missing_prototypes = 1;
695  else if (!strcmp (p, "-Wno-missing-prototypes"))
696    warn_missing_prototypes = 0;
697  else if (!strcmp (p, "-Wmissing-declarations"))
698    warn_missing_declarations = 1;
699  else if (!strcmp (p, "-Wno-missing-declarations"))
700    warn_missing_declarations = 0;
701  else if (!strcmp (p, "-Wredundant-decls"))
702    warn_redundant_decls = 1;
703  else if (!strcmp (p, "-Wno-redundant-decls"))
704    warn_redundant_decls = 0;
705  else if (!strcmp (p, "-Wnested-externs"))
706    warn_nested_externs = 1;
707  else if (!strcmp (p, "-Wno-nested-externs"))
708    warn_nested_externs = 0;
709  else if (!strcmp (p, "-Wtraditional"))
710    warn_traditional = 1;
711  else if (!strcmp (p, "-Wno-traditional"))
712    warn_traditional = 0;
713  else if (!strncmp (p, "-Wformat=", 9))
714    set_Wformat (atoi (p + 9));
715  else if (!strcmp (p, "-Wformat"))
716    set_Wformat (1);
717  else if (!strcmp (p, "-Wno-format"))
718    set_Wformat (0);
719  else if (!strcmp (p, "-Wformat-y2k"))
720    warn_format_y2k = 1;
721  else if (!strcmp (p, "-Wno-format-y2k"))
722    warn_format_y2k = 0;
723  else if (!strcmp (p, "-Wformat-extra-args"))
724    warn_format_extra_args = 1;
725  else if (!strcmp (p, "-Wno-format-extra-args"))
726    warn_format_extra_args = 0;
727  else if (!strcmp (p, "-Wformat-nonliteral"))
728    warn_format_nonliteral = 1;
729  else if (!strcmp (p, "-Wno-format-nonliteral"))
730    warn_format_nonliteral = 0;
731  else if (!strcmp (p, "-Wformat-security"))
732    warn_format_security = 1;
733  else if (!strcmp (p, "-Wno-format-security"))
734    warn_format_security = 0;
735  else if (!strcmp (p, "-Wchar-subscripts"))
736    warn_char_subscripts = 1;
737  else if (!strcmp (p, "-Wno-char-subscripts"))
738    warn_char_subscripts = 0;
739  else if (!strcmp (p, "-Wconversion"))
740    warn_conversion = 1;
741  else if (!strcmp (p, "-Wno-conversion"))
742    warn_conversion = 0;
743  else if (!strcmp (p, "-Wparentheses"))
744    warn_parentheses = 1;
745  else if (!strcmp (p, "-Wno-parentheses"))
746    warn_parentheses = 0;
747  else if (!strcmp (p, "-Wreturn-type"))
748    warn_return_type = 1;
749  else if (!strcmp (p, "-Wno-return-type"))
750    warn_return_type = 0;
751  else if (!strcmp (p, "-Wsequence-point"))
752    warn_sequence_point = 1;
753  else if (!strcmp (p, "-Wno-sequence-point"))
754    warn_sequence_point = 0;
755  else if (!strcmp (p, "-Wcomment"))
756    ; /* cpp handles this one.  */
757  else if (!strcmp (p, "-Wno-comment"))
758    ; /* cpp handles this one.  */
759  else if (!strcmp (p, "-Wcomments"))
760    ; /* cpp handles this one.  */
761  else if (!strcmp (p, "-Wno-comments"))
762    ; /* cpp handles this one.  */
763  else if (!strcmp (p, "-Wtrigraphs"))
764    ; /* cpp handles this one.  */
765  else if (!strcmp (p, "-Wno-trigraphs"))
766    ; /* cpp handles this one.  */
767  else if (!strcmp (p, "-Wundef"))
768    ; /* cpp handles this one.  */
769  else if (!strcmp (p, "-Wno-undef"))
770    ; /* cpp handles this one.  */
771  else if (!strcmp (p, "-Wimport"))
772    ; /* cpp handles this one.  */
773  else if (!strcmp (p, "-Wno-import"))
774    ; /* cpp handles this one.  */
775  else if (!strcmp (p, "-Wmissing-braces"))
776    warn_missing_braces = 1;
777  else if (!strcmp (p, "-Wno-missing-braces"))
778    warn_missing_braces = 0;
779  else if (!strcmp (p, "-Wmain"))
780    warn_main = 1;
781  else if (!strcmp (p, "-Wno-main"))
782    warn_main = -1;
783  else if (!strcmp (p, "-Wsign-compare"))
784    warn_sign_compare = 1;
785  else if (!strcmp (p, "-Wno-sign-compare"))
786    warn_sign_compare = 0;
787  else if (!strcmp (p, "-Wfloat-equal"))
788    warn_float_equal = 1;
789  else if (!strcmp (p, "-Wno-float-equal"))
790    warn_float_equal = 0;
791  else if (!strcmp (p, "-Wmultichar"))
792    warn_multichar = 1;
793  else if (!strcmp (p, "-Wno-multichar"))
794    warn_multichar = 0;
795  else if (!strcmp (p, "-Wdiv-by-zero"))
796    warn_div_by_zero = 1;
797  else if (!strcmp (p, "-Wno-div-by-zero"))
798    warn_div_by_zero = 0;
799  else if (!strcmp (p, "-Wunknown-pragmas"))
800    /* Set to greater than 1, so that even unknown pragmas in system
801       headers will be warned about.  */
802    warn_unknown_pragmas = 2;
803  else if (!strcmp (p, "-Wno-unknown-pragmas"))
804    warn_unknown_pragmas = 0;
805  else if (!strcmp (p, "-Wall"))
806    {
807      /* We save the value of warn_uninitialized, since if they put
808	 -Wuninitialized on the command line, we need to generate a
809	 warning about not using it without also specifying -O.  */
810      if (warn_uninitialized != 1)
811	warn_uninitialized = 2;
812      warn_implicit_int = 1;
813      mesg_implicit_function_declaration = 1;
814      warn_return_type = 1;
815      set_Wunused (1);
816      warn_switch = 1;
817      set_Wformat (1);
818      warn_char_subscripts = 1;
819      warn_parentheses = 1;
820      warn_sequence_point = 1;
821      warn_missing_braces = 1;
822      /* We set this to 2 here, but 1 in -Wmain, so -ffreestanding can turn
823	 it off only if it's not explicit.  */
824      warn_main = 2;
825      /* Only warn about unknown pragmas that are not in system headers.  */
826      warn_unknown_pragmas = 1;
827    }
828  else
829    return strings_processed;
830
831  return 1;
832}
833
834void
835c_print_identifier (file, node, indent)
836     FILE *file;
837     tree node;
838     int indent;
839{
840  print_node (file, "global", IDENTIFIER_GLOBAL_VALUE (node), indent + 4);
841  print_node (file, "local", IDENTIFIER_LOCAL_VALUE (node), indent + 4);
842  print_node (file, "label", IDENTIFIER_LABEL_VALUE (node), indent + 4);
843  print_node (file, "implicit", IDENTIFIER_IMPLICIT_DECL (node), indent + 4);
844  print_node (file, "error locus", IDENTIFIER_ERROR_LOCUS (node), indent + 4);
845  print_node (file, "limbo value", IDENTIFIER_LIMBO_VALUE (node), indent + 4);
846  if (C_IS_RESERVED_WORD (node))
847    {
848      tree rid = ridpointers[C_RID_CODE (node)];
849      indent_to (file, indent + 4);
850      fprintf (file, "rid ");
851      fprintf (file, HOST_PTR_PRINTF, (void *)rid);
852      fprintf (file, " \"%s\"", IDENTIFIER_POINTER (rid));
853    }
854}
855
856/* Hook called at end of compilation to assume 1 elt
857   for a top-level tentative array defn that wasn't complete before.  */
858
859void
860finish_incomplete_decl (decl)
861     tree decl;
862{
863  if (TREE_CODE (decl) == VAR_DECL)
864    {
865      tree type = TREE_TYPE (decl);
866      if (type != error_mark_node
867	  && TREE_CODE (type) == ARRAY_TYPE
868	  && ! DECL_EXTERNAL (decl)
869	  && TYPE_DOMAIN (type) == 0)
870	{
871	  warning_with_decl (decl, "array `%s' assumed to have one element");
872
873	  complete_array_type (type, NULL_TREE, 1);
874
875	  layout_decl (decl, 0);
876	}
877    }
878}
879
880/* Create a new `struct binding_level'.  */
881
882static struct binding_level *
883make_binding_level ()
884{
885  /* NOSTRICT */
886  return (struct binding_level *) xmalloc (sizeof (struct binding_level));
887}
888
889/* Nonzero if we are currently in the global binding level.  */
890
891int
892global_bindings_p ()
893{
894  return current_binding_level == global_binding_level;
895}
896
897void
898keep_next_level ()
899{
900  keep_next_level_flag = 1;
901}
902
903/* Nonzero if the current level needs to have a BLOCK made.  */
904
905int
906kept_level_p ()
907{
908  return ((current_binding_level->keep_if_subblocks
909	   && current_binding_level->blocks != 0)
910	  || current_binding_level->keep
911	  || current_binding_level->names != 0
912	  || (current_binding_level->tags != 0
913	      && !current_binding_level->tag_transparent));
914}
915
916/* Identify this binding level as a level of parameters.
917   DEFINITION_FLAG is 1 for a definition, 0 for a declaration.
918   But it turns out there is no way to pass the right value for
919   DEFINITION_FLAG, so we ignore it.  */
920
921void
922declare_parm_level (definition_flag)
923     int definition_flag ATTRIBUTE_UNUSED;
924{
925  current_binding_level->parm_flag = 1;
926}
927
928/* Nonzero if currently making parm declarations.  */
929
930int
931in_parm_level_p ()
932{
933  return current_binding_level->parm_flag;
934}
935
936/* Enter a new binding level.
937   If TAG_TRANSPARENT is nonzero, do so only for the name space of variables,
938   not for that of tags.  */
939
940void
941pushlevel (tag_transparent)
942     int tag_transparent;
943{
944  struct binding_level *newlevel = NULL_BINDING_LEVEL;
945
946  /* If this is the top level of a function,
947     just make sure that NAMED_LABELS is 0.  */
948
949  if (current_binding_level == global_binding_level)
950    {
951      named_labels = 0;
952    }
953
954  /* Reuse or create a struct for this binding level.  */
955
956  if (free_binding_level)
957    {
958      newlevel = free_binding_level;
959      free_binding_level = free_binding_level->level_chain;
960    }
961  else
962    {
963      newlevel = make_binding_level ();
964    }
965
966  /* Add this level to the front of the chain (stack) of levels that
967     are active.  */
968
969  *newlevel = clear_binding_level;
970  newlevel->tag_transparent
971    = (tag_transparent
972       || (current_binding_level
973	   ? current_binding_level->subblocks_tag_transparent
974	   : 0));
975  newlevel->level_chain = current_binding_level;
976  current_binding_level = newlevel;
977  newlevel->keep = keep_next_level_flag;
978  keep_next_level_flag = 0;
979  newlevel->keep_if_subblocks = keep_next_if_subblocks;
980  keep_next_if_subblocks = 0;
981}
982
983/* Clear the limbo values of all identifiers defined in BLOCK or a subblock.  */
984
985static void
986clear_limbo_values (block)
987     tree block;
988{
989  tree tem;
990
991  for (tem = BLOCK_VARS (block); tem; tem = TREE_CHAIN (tem))
992    if (DECL_NAME (tem) != 0)
993      IDENTIFIER_LIMBO_VALUE (DECL_NAME (tem)) = 0;
994
995  for (tem = BLOCK_SUBBLOCKS (block); tem; tem = TREE_CHAIN (tem))
996    clear_limbo_values (tem);
997}
998
999/* Exit a binding level.
1000   Pop the level off, and restore the state of the identifier-decl mappings
1001   that were in effect when this level was entered.
1002
1003   If KEEP is nonzero, this level had explicit declarations, so
1004   and create a "block" (a BLOCK node) for the level
1005   to record its declarations and subblocks for symbol table output.
1006
1007   If FUNCTIONBODY is nonzero, this level is the body of a function,
1008   so create a block as if KEEP were set and also clear out all
1009   label names.
1010
1011   If REVERSE is nonzero, reverse the order of decls before putting
1012   them into the BLOCK.  */
1013
1014tree
1015poplevel (keep, reverse, functionbody)
1016     int keep;
1017     int reverse;
1018     int functionbody;
1019{
1020  tree link;
1021  /* The chain of decls was accumulated in reverse order.
1022     Put it into forward order, just for cleanliness.  */
1023  tree decls;
1024  tree tags = current_binding_level->tags;
1025  tree subblocks = current_binding_level->blocks;
1026  tree block = 0;
1027  tree decl;
1028  int block_previously_created;
1029
1030  keep |= current_binding_level->keep;
1031
1032  /* This warning is turned off because it causes warnings for
1033     declarations like `extern struct foo *x'.  */
1034#if 0
1035  /* Warn about incomplete structure types in this level.  */
1036  for (link = tags; link; link = TREE_CHAIN (link))
1037    if (!COMPLETE_TYPE_P (TREE_VALUE (link)))
1038      {
1039	tree type = TREE_VALUE (link);
1040	tree type_name = TYPE_NAME (type);
1041	char *id = IDENTIFIER_POINTER (TREE_CODE (type_name) == IDENTIFIER_NODE
1042				       ? type_name
1043				       : DECL_NAME (type_name));
1044	switch (TREE_CODE (type))
1045	  {
1046	  case RECORD_TYPE:
1047	    error ("`struct %s' incomplete in scope ending here", id);
1048	    break;
1049	  case UNION_TYPE:
1050	    error ("`union %s' incomplete in scope ending here", id);
1051	    break;
1052	  case ENUMERAL_TYPE:
1053	    error ("`enum %s' incomplete in scope ending here", id);
1054	    break;
1055	  }
1056      }
1057#endif /* 0 */
1058
1059  /* Get the decls in the order they were written.
1060     Usually current_binding_level->names is in reverse order.
1061     But parameter decls were previously put in forward order.  */
1062
1063  if (reverse)
1064    current_binding_level->names
1065      = decls = nreverse (current_binding_level->names);
1066  else
1067    decls = current_binding_level->names;
1068
1069  /* Output any nested inline functions within this block
1070     if they weren't already output.  */
1071
1072  for (decl = decls; decl; decl = TREE_CHAIN (decl))
1073    if (TREE_CODE (decl) == FUNCTION_DECL
1074	&& ! TREE_ASM_WRITTEN (decl)
1075	&& DECL_INITIAL (decl) != 0
1076	&& TREE_ADDRESSABLE (decl))
1077      {
1078	/* If this decl was copied from a file-scope decl
1079	   on account of a block-scope extern decl,
1080	   propagate TREE_ADDRESSABLE to the file-scope decl.
1081
1082	   DECL_ABSTRACT_ORIGIN can be set to itself if warn_return_type is
1083	   true, since then the decl goes through save_for_inline_copying.  */
1084	if (DECL_ABSTRACT_ORIGIN (decl) != 0
1085	    && DECL_ABSTRACT_ORIGIN (decl) != decl)
1086	  TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (decl)) = 1;
1087      }
1088
1089  /* We used to warn about unused variables in expand_end_bindings,
1090     i.e. while generating RTL.  But in function-at-a-time mode we may
1091     choose to never expand a function at all (e.g. auto inlining), so
1092     we do this explicitly now.  */
1093  warn_about_unused_variables (getdecls ());
1094
1095  /* If there were any declarations or structure tags in that level,
1096     or if this level is a function body,
1097     create a BLOCK to record them for the life of this function.  */
1098
1099  block = 0;
1100  block_previously_created = (current_binding_level->this_block != 0);
1101  if (block_previously_created)
1102    block = current_binding_level->this_block;
1103  else if (keep || functionbody
1104	   || (current_binding_level->keep_if_subblocks && subblocks != 0))
1105    block = make_node (BLOCK);
1106  if (block != 0)
1107    {
1108      BLOCK_VARS (block) = decls;
1109      BLOCK_SUBBLOCKS (block) = subblocks;
1110    }
1111
1112  /* In each subblock, record that this is its superior.  */
1113
1114  for (link = subblocks; link; link = TREE_CHAIN (link))
1115    BLOCK_SUPERCONTEXT (link) = block;
1116
1117  /* Clear out the meanings of the local variables of this level.  */
1118
1119  for (link = decls; link; link = TREE_CHAIN (link))
1120    {
1121      if (DECL_NAME (link) != 0)
1122	{
1123	  /* If the ident. was used or addressed via a local extern decl,
1124	     don't forget that fact.  */
1125	  if (DECL_EXTERNAL (link))
1126	    {
1127	      if (TREE_USED (link))
1128		TREE_USED (DECL_NAME (link)) = 1;
1129	      if (TREE_ADDRESSABLE (link))
1130		TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (link)) = 1;
1131	    }
1132	  IDENTIFIER_LOCAL_VALUE (DECL_NAME (link)) = 0;
1133	}
1134    }
1135
1136  /* Restore all name-meanings of the outer levels
1137     that were shadowed by this level.  */
1138
1139  for (link = current_binding_level->shadowed; link; link = TREE_CHAIN (link))
1140    IDENTIFIER_LOCAL_VALUE (TREE_PURPOSE (link)) = TREE_VALUE (link);
1141
1142  /* If the level being exited is the top level of a function,
1143     check over all the labels, and clear out the current
1144     (function local) meanings of their names.  */
1145
1146  if (functionbody)
1147    {
1148      clear_limbo_values (block);
1149
1150      /* If this is the top level block of a function,
1151	 the vars are the function's parameters.
1152	 Don't leave them in the BLOCK because they are
1153	 found in the FUNCTION_DECL instead.  */
1154
1155      BLOCK_VARS (block) = 0;
1156
1157      /* Clear out the definitions of all label names,
1158	 since their scopes end here,
1159	 and add them to BLOCK_VARS.  */
1160
1161      for (link = named_labels; link; link = TREE_CHAIN (link))
1162	{
1163	  tree label = TREE_VALUE (link);
1164
1165	  if (DECL_INITIAL (label) == 0)
1166	    {
1167	      error_with_decl (label, "label `%s' used but not defined");
1168	      /* Avoid crashing later.  */
1169	      define_label (input_filename, lineno,
1170			    DECL_NAME (label));
1171	    }
1172	  else if (warn_unused_label && !TREE_USED (label))
1173	    warning_with_decl (label, "label `%s' defined but not used");
1174	  IDENTIFIER_LABEL_VALUE (DECL_NAME (label)) = 0;
1175
1176	  /* Put the labels into the "variables" of the
1177	     top-level block, so debugger can see them.  */
1178	  TREE_CHAIN (label) = BLOCK_VARS (block);
1179	  BLOCK_VARS (block) = label;
1180	}
1181    }
1182
1183  /* Pop the current level, and free the structure for reuse.  */
1184
1185  {
1186    struct binding_level *level = current_binding_level;
1187    current_binding_level = current_binding_level->level_chain;
1188
1189    level->level_chain = free_binding_level;
1190    free_binding_level = level;
1191  }
1192
1193  /* Dispose of the block that we just made inside some higher level.  */
1194  if (functionbody)
1195    DECL_INITIAL (current_function_decl) = block;
1196  else if (block)
1197    {
1198      if (!block_previously_created)
1199	current_binding_level->blocks
1200	  = chainon (current_binding_level->blocks, block);
1201    }
1202  /* If we did not make a block for the level just exited,
1203     any blocks made for inner levels
1204     (since they cannot be recorded as subblocks in that level)
1205     must be carried forward so they will later become subblocks
1206     of something else.  */
1207  else if (subblocks)
1208    current_binding_level->blocks
1209      = chainon (current_binding_level->blocks, subblocks);
1210
1211  /* Set the TYPE_CONTEXTs for all of the tagged types belonging to this
1212     binding contour so that they point to the appropriate construct, i.e.
1213     either to the current FUNCTION_DECL node, or else to the BLOCK node
1214     we just constructed.
1215
1216     Note that for tagged types whose scope is just the formal parameter
1217     list for some function type specification, we can't properly set
1218     their TYPE_CONTEXTs here, because we don't have a pointer to the
1219     appropriate FUNCTION_TYPE node readily available to us.  For those
1220     cases, the TYPE_CONTEXTs of the relevant tagged type nodes get set
1221     in `grokdeclarator' as soon as we have created the FUNCTION_TYPE
1222     node which will represent the "scope" for these "parameter list local"
1223     tagged types.  */
1224
1225  if (functionbody)
1226    for (link = tags; link; link = TREE_CHAIN (link))
1227      TYPE_CONTEXT (TREE_VALUE (link)) = current_function_decl;
1228  else if (block)
1229    for (link = tags; link; link = TREE_CHAIN (link))
1230      TYPE_CONTEXT (TREE_VALUE (link)) = block;
1231
1232  if (block)
1233    TREE_USED (block) = 1;
1234
1235  return block;
1236}
1237
1238/* Insert BLOCK at the end of the list of subblocks of the
1239   current binding level.  This is used when a BIND_EXPR is expanded,
1240   to handle the BLOCK node inside the BIND_EXPR.  */
1241
1242void
1243insert_block (block)
1244     tree block;
1245{
1246  TREE_USED (block) = 1;
1247  current_binding_level->blocks
1248    = chainon (current_binding_level->blocks, block);
1249}
1250
1251/* Set the BLOCK node for the innermost scope
1252   (the one we are currently in).  */
1253
1254void
1255set_block (block)
1256     tree block;
1257{
1258  current_binding_level->this_block = block;
1259  current_binding_level->names = chainon (current_binding_level->names,
1260					  BLOCK_VARS (block));
1261  current_binding_level->blocks = chainon (current_binding_level->blocks,
1262					   BLOCK_SUBBLOCKS (block));
1263}
1264
1265void
1266push_label_level ()
1267{
1268  struct binding_level *newlevel;
1269
1270  /* Reuse or create a struct for this binding level.  */
1271
1272  if (free_binding_level)
1273    {
1274      newlevel = free_binding_level;
1275      free_binding_level = free_binding_level->level_chain;
1276    }
1277  else
1278    {
1279      newlevel = make_binding_level ();
1280    }
1281
1282  /* Add this level to the front of the chain (stack) of label levels.  */
1283
1284  newlevel->level_chain = label_level_chain;
1285  label_level_chain = newlevel;
1286
1287  newlevel->names = named_labels;
1288  newlevel->shadowed = shadowed_labels;
1289  named_labels = 0;
1290  shadowed_labels = 0;
1291}
1292
1293void
1294pop_label_level ()
1295{
1296  struct binding_level *level = label_level_chain;
1297  tree link, prev;
1298
1299  /* Clear out the definitions of the declared labels in this level.
1300     Leave in the list any ordinary, non-declared labels.  */
1301  for (link = named_labels, prev = 0; link;)
1302    {
1303      if (C_DECLARED_LABEL_FLAG (TREE_VALUE (link)))
1304	{
1305	  if (DECL_SOURCE_LINE (TREE_VALUE (link)) == 0)
1306	    {
1307	      error_with_decl (TREE_VALUE (link),
1308			       "label `%s' used but not defined");
1309	      /* Avoid crashing later.  */
1310	      define_label (input_filename, lineno,
1311			    DECL_NAME (TREE_VALUE (link)));
1312	    }
1313	  else if (warn_unused_label && !TREE_USED (TREE_VALUE (link)))
1314	    warning_with_decl (TREE_VALUE (link),
1315			       "label `%s' defined but not used");
1316	  IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link))) = 0;
1317
1318	  /* Delete this element from the list.  */
1319	  link = TREE_CHAIN (link);
1320	  if (prev)
1321	    TREE_CHAIN (prev) = link;
1322	  else
1323	    named_labels = link;
1324	}
1325      else
1326	{
1327	  prev = link;
1328	  link = TREE_CHAIN (link);
1329	}
1330    }
1331
1332  /* Bring back all the labels that were shadowed.  */
1333  for (link = shadowed_labels; link; link = TREE_CHAIN (link))
1334    if (DECL_NAME (TREE_VALUE (link)) != 0)
1335      IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link)))
1336	= TREE_VALUE (link);
1337
1338  named_labels = chainon (named_labels, level->names);
1339  shadowed_labels = level->shadowed;
1340
1341  /* Pop the current level, and free the structure for reuse.  */
1342  label_level_chain = label_level_chain->level_chain;
1343  level->level_chain = free_binding_level;
1344  free_binding_level = level;
1345}
1346
1347/* Push a definition or a declaration of struct, union or enum tag "name".
1348   "type" should be the type node.
1349   We assume that the tag "name" is not already defined.
1350
1351   Note that the definition may really be just a forward reference.
1352   In that case, the TYPE_SIZE will be zero.  */
1353
1354void
1355pushtag (name, type)
1356     tree name, type;
1357{
1358  struct binding_level *b;
1359
1360  /* Find the proper binding level for this type tag.  */
1361
1362  for (b = current_binding_level; b->tag_transparent; b = b->level_chain)
1363    continue;
1364
1365  if (name)
1366    {
1367      /* Record the identifier as the type's name if it has none.  */
1368
1369      if (TYPE_NAME (type) == 0)
1370	TYPE_NAME (type) = name;
1371    }
1372
1373  b->tags = tree_cons (name, type, b->tags);
1374
1375  /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
1376     tagged type we just added to the current binding level.  This fake
1377     NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
1378     to output a representation of a tagged type, and it also gives
1379     us a convenient place to record the "scope start" address for the
1380     tagged type.  */
1381
1382  TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));
1383
1384  /* An approximation for now, so we can tell this is a function-scope tag.
1385     This will be updated in poplevel.  */
1386  TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
1387}
1388
1389/* Handle when a new declaration NEWDECL
1390   has the same name as an old one OLDDECL
1391   in the same binding contour.
1392   Prints an error message if appropriate.
1393
1394   If safely possible, alter OLDDECL to look like NEWDECL, and return 1.
1395   Otherwise, return 0.
1396
1397   When DIFFERENT_BINDING_LEVEL is true, NEWDECL is an external declaration,
1398   and OLDDECL is in an outer binding level and should thus not be changed.  */
1399
1400static int
1401duplicate_decls (newdecl, olddecl, different_binding_level)
1402     tree newdecl, olddecl;
1403     int different_binding_level;
1404{
1405  int types_match = comptypes (TREE_TYPE (newdecl), TREE_TYPE (olddecl));
1406  int new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
1407			   && DECL_INITIAL (newdecl) != 0);
1408  tree oldtype = TREE_TYPE (olddecl);
1409  tree newtype = TREE_TYPE (newdecl);
1410  int errmsg = 0;
1411
1412  if (DECL_P (olddecl))
1413    {
1414      if (TREE_CODE (newdecl) == FUNCTION_DECL
1415	  && TREE_CODE (olddecl) == FUNCTION_DECL
1416	  && (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl)))
1417	{
1418	  if (DECL_DECLARED_INLINE_P (newdecl)
1419	      && DECL_UNINLINABLE (newdecl)
1420	      && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1421	    /* Already warned elsewhere.  */;
1422	  else if (DECL_DECLARED_INLINE_P (olddecl)
1423		   && DECL_UNINLINABLE (olddecl)
1424		   && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1425	    /* Already warned.  */;
1426	  else if (DECL_DECLARED_INLINE_P (newdecl)
1427		   && ! DECL_DECLARED_INLINE_P (olddecl)
1428		   && DECL_UNINLINABLE (olddecl)
1429		   && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1430	    {
1431	      warning_with_decl (newdecl,
1432				 "function `%s' redeclared as inline");
1433	      warning_with_decl (olddecl,
1434				 "previous declaration of function `%s' with attribute noinline");
1435	    }
1436	  else if (DECL_DECLARED_INLINE_P (olddecl)
1437		   && DECL_UNINLINABLE (newdecl)
1438		   && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1439	    {
1440	      warning_with_decl (newdecl,
1441				 "function `%s' redeclared with attribute noinline");
1442	      warning_with_decl (olddecl,
1443				 "previous declaration of function `%s' was inline");
1444	    }
1445	}
1446
1447      DECL_ATTRIBUTES (newdecl)
1448	= (*targetm.merge_decl_attributes) (olddecl, newdecl);
1449    }
1450
1451  if (TREE_CODE (newtype) == ERROR_MARK
1452      || TREE_CODE (oldtype) == ERROR_MARK)
1453    types_match = 0;
1454
1455  /* New decl is completely inconsistent with the old one =>
1456     tell caller to replace the old one.
1457     This is always an error except in the case of shadowing a builtin.  */
1458  if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1459    {
1460      if (TREE_CODE (olddecl) == FUNCTION_DECL
1461	  && (DECL_BUILT_IN (olddecl)
1462	      || DECL_BUILT_IN_NONANSI (olddecl)))
1463	{
1464	  /* If you declare a built-in or predefined function name as static,
1465	     the old definition is overridden,
1466	     but optionally warn this was a bad choice of name.  */
1467	  if (!TREE_PUBLIC (newdecl))
1468	    {
1469	      if (!warn_shadow)
1470		;
1471	      else if (DECL_BUILT_IN (olddecl))
1472		warning_with_decl (newdecl, "shadowing built-in function `%s'");
1473	      else
1474		warning_with_decl (newdecl, "shadowing library function `%s'");
1475	    }
1476	  /* Likewise, if the built-in is not ansi, then programs can
1477	     override it even globally without an error.  */
1478	  else if (! DECL_BUILT_IN (olddecl))
1479	    warning_with_decl (newdecl,
1480			       "library function `%s' declared as non-function");
1481
1482	  else if (DECL_BUILT_IN_NONANSI (olddecl))
1483	    warning_with_decl (newdecl,
1484			       "built-in function `%s' declared as non-function");
1485	  else
1486	    warning_with_decl (newdecl,
1487			       "built-in function `%s' declared as non-function");
1488	}
1489      else
1490	{
1491	  error_with_decl (newdecl, "`%s' redeclared as different kind of symbol");
1492	  error_with_decl (olddecl, "previous declaration of `%s'");
1493	}
1494
1495      return 0;
1496    }
1497
1498  /* For real parm decl following a forward decl,
1499     return 1 so old decl will be reused.  */
1500  if (types_match && TREE_CODE (newdecl) == PARM_DECL
1501      && TREE_ASM_WRITTEN (olddecl) && ! TREE_ASM_WRITTEN (newdecl))
1502    return 1;
1503
1504  /* The new declaration is the same kind of object as the old one.
1505     The declarations may partially match.  Print warnings if they don't
1506     match enough.  Ultimately, copy most of the information from the new
1507     decl to the old one, and keep using the old one.  */
1508
1509  if (flag_traditional && TREE_CODE (newdecl) == FUNCTION_DECL
1510      && IDENTIFIER_IMPLICIT_DECL (DECL_NAME (newdecl)) == olddecl
1511      && DECL_INITIAL (olddecl) == 0)
1512    /* If -traditional, avoid error for redeclaring fcn
1513       after implicit decl.  */
1514    ;
1515  else if (TREE_CODE (olddecl) == FUNCTION_DECL
1516	   && DECL_BUILT_IN (olddecl))
1517    {
1518      /* A function declaration for a built-in function.  */
1519      if (!TREE_PUBLIC (newdecl))
1520	{
1521	  /* If you declare a built-in function name as static, the
1522	     built-in definition is overridden,
1523	     but optionally warn this was a bad choice of name.  */
1524	  if (warn_shadow)
1525	    warning_with_decl (newdecl, "shadowing built-in function `%s'");
1526	  /* Discard the old built-in function.  */
1527	  return 0;
1528	}
1529      else if (!types_match)
1530	{
1531	  /* Accept the return type of the new declaration if same modes.  */
1532	  tree oldreturntype = TREE_TYPE (oldtype);
1533	  tree newreturntype = TREE_TYPE (newtype);
1534
1535	  if (TYPE_MODE (oldreturntype) == TYPE_MODE (newreturntype))
1536	    {
1537	      /* Function types may be shared, so we can't just modify
1538		 the return type of olddecl's function type.  */
1539	      tree trytype
1540		= build_function_type (newreturntype,
1541				       TYPE_ARG_TYPES (oldtype));
1542	      trytype = build_type_attribute_variant (trytype,
1543						      TYPE_ATTRIBUTES (oldtype));
1544
1545              types_match = comptypes (newtype, trytype);
1546	      if (types_match)
1547		oldtype = trytype;
1548	    }
1549	  /* Accept harmless mismatch in first argument type also.
1550	     This is for the ffs and fprintf builtins.  */
1551	  if (TYPE_ARG_TYPES (TREE_TYPE (newdecl)) != 0
1552	      && TYPE_ARG_TYPES (oldtype) != 0
1553	      && TREE_VALUE (TYPE_ARG_TYPES (newtype)) != 0
1554	      && TREE_VALUE (TYPE_ARG_TYPES (oldtype)) != 0
1555	      && (TYPE_MODE (TREE_VALUE (TYPE_ARG_TYPES (newtype)))
1556		  == TYPE_MODE (TREE_VALUE (TYPE_ARG_TYPES (oldtype)))))
1557	    {
1558	      /* Function types may be shared, so we can't just modify
1559		 the return type of olddecl's function type.  */
1560	      tree trytype
1561		= build_function_type (TREE_TYPE (oldtype),
1562				       tree_cons (NULL_TREE,
1563						  TREE_VALUE (TYPE_ARG_TYPES (newtype)),
1564						  TREE_CHAIN (TYPE_ARG_TYPES (oldtype))));
1565	      trytype = build_type_attribute_variant (trytype,
1566						      TYPE_ATTRIBUTES (oldtype));
1567
1568	      types_match = comptypes (newtype, trytype);
1569	      if (types_match)
1570		oldtype = trytype;
1571	    }
1572	  if (! different_binding_level)
1573	    TREE_TYPE (olddecl) = oldtype;
1574	}
1575      else if (TYPE_ARG_TYPES (oldtype) == NULL
1576	       && TYPE_ARG_TYPES (newtype) != NULL)
1577	{
1578	  /* For bcmp, bzero, fputs the builtin type has arguments not
1579	     specified.  Use the ones from the prototype so that type checking
1580	     is done for them.  */
1581	  tree trytype
1582	    = build_function_type (TREE_TYPE (oldtype),
1583				   TYPE_ARG_TYPES (newtype));
1584	  trytype = build_type_attribute_variant (trytype,
1585						  TYPE_ATTRIBUTES (oldtype));
1586
1587	  oldtype = trytype;
1588	  if (! different_binding_level)
1589	    TREE_TYPE (olddecl) = oldtype;
1590	}
1591      if (!types_match)
1592	{
1593	  /* If types don't match for a built-in, throw away the built-in.  */
1594	  warning_with_decl (newdecl, "conflicting types for built-in function `%s'");
1595	  return 0;
1596	}
1597    }
1598  else if (TREE_CODE (olddecl) == FUNCTION_DECL
1599	   && DECL_SOURCE_LINE (olddecl) == 0)
1600    {
1601      /* A function declaration for a predeclared function
1602	 that isn't actually built in.  */
1603      if (!TREE_PUBLIC (newdecl))
1604	{
1605	  /* If you declare it as static, the
1606	     default definition is overridden.  */
1607	  return 0;
1608	}
1609      else if (!types_match)
1610	{
1611	  /* If the types don't match, preserve volatility indication.
1612	     Later on, we will discard everything else about the
1613	     default declaration.  */
1614	  TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1615	}
1616    }
1617  /* Permit char *foo () to match void *foo (...) if not pedantic,
1618     if one of them came from a system header file.  */
1619  else if (!types_match
1620	   && TREE_CODE (olddecl) == FUNCTION_DECL
1621	   && TREE_CODE (newdecl) == FUNCTION_DECL
1622	   && TREE_CODE (TREE_TYPE (oldtype)) == POINTER_TYPE
1623	   && TREE_CODE (TREE_TYPE (newtype)) == POINTER_TYPE
1624	   && (DECL_IN_SYSTEM_HEADER (olddecl)
1625	       || DECL_IN_SYSTEM_HEADER (newdecl))
1626	   && ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (newtype))) == void_type_node
1627		&& TYPE_ARG_TYPES (oldtype) == 0
1628		&& self_promoting_args_p (TYPE_ARG_TYPES (newtype))
1629		&& TREE_TYPE (TREE_TYPE (oldtype)) == char_type_node)
1630	       ||
1631	       (TREE_TYPE (TREE_TYPE (newtype)) == char_type_node
1632		&& TYPE_ARG_TYPES (newtype) == 0
1633		&& self_promoting_args_p (TYPE_ARG_TYPES (oldtype))
1634		&& TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)))
1635    {
1636      if (pedantic)
1637	pedwarn_with_decl (newdecl, "conflicting types for `%s'");
1638      /* Make sure we keep void * as ret type, not char *.  */
1639      if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)
1640	TREE_TYPE (newdecl) = newtype = oldtype;
1641
1642      /* Set DECL_IN_SYSTEM_HEADER, so that if we see another declaration
1643	 we will come back here again.  */
1644      DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1645    }
1646  else if (!types_match
1647	   /* Permit char *foo (int, ...); followed by char *foo ();
1648	      if not pedantic.  */
1649	   && ! (TREE_CODE (olddecl) == FUNCTION_DECL
1650		 && ! pedantic
1651		 /* Return types must still match.  */
1652		 && comptypes (TREE_TYPE (oldtype),
1653			       TREE_TYPE (newtype))
1654		 && TYPE_ARG_TYPES (newtype) == 0))
1655    {
1656      error_with_decl (newdecl, "conflicting types for `%s'");
1657      /* Check for function type mismatch
1658	 involving an empty arglist vs a nonempty one.  */
1659      if (TREE_CODE (olddecl) == FUNCTION_DECL
1660	  && comptypes (TREE_TYPE (oldtype),
1661			TREE_TYPE (newtype))
1662	  && ((TYPE_ARG_TYPES (oldtype) == 0
1663	       && DECL_INITIAL (olddecl) == 0)
1664	      ||
1665	      (TYPE_ARG_TYPES (newtype) == 0
1666	       && DECL_INITIAL (newdecl) == 0)))
1667	{
1668	  /* Classify the problem further.  */
1669	  tree t = TYPE_ARG_TYPES (oldtype);
1670	  if (t == 0)
1671	    t = TYPE_ARG_TYPES (newtype);
1672	  for (; t; t = TREE_CHAIN (t))
1673	    {
1674	      tree type = TREE_VALUE (t);
1675
1676	      if (TREE_CHAIN (t) == 0
1677		  && TYPE_MAIN_VARIANT (type) != void_type_node)
1678		{
1679		  error ("a parameter list with an ellipsis can't match an empty parameter name list declaration");
1680		  break;
1681		}
1682
1683	      if (simple_type_promotes_to (type) != NULL_TREE)
1684		{
1685		  error ("an argument type that has a default promotion can't match an empty parameter name list declaration");
1686		  break;
1687		}
1688	    }
1689	}
1690      error_with_decl (olddecl, "previous declaration of `%s'");
1691    }
1692  else
1693    {
1694      errmsg = redeclaration_error_message (newdecl, olddecl);
1695      if (errmsg)
1696	{
1697	  switch (errmsg)
1698	    {
1699	    case 1:
1700	      error_with_decl (newdecl, "redefinition of `%s'");
1701	      break;
1702	    case 2:
1703	      error_with_decl (newdecl, "redeclaration of `%s'");
1704	      break;
1705	    case 3:
1706	      error_with_decl (newdecl, "conflicting declarations of `%s'");
1707	      break;
1708	    default:
1709	      abort ();
1710	    }
1711
1712	  error_with_decl (olddecl,
1713			   ((DECL_INITIAL (olddecl)
1714			     && current_binding_level == global_binding_level)
1715			    ? "`%s' previously defined here"
1716			    : "`%s' previously declared here"));
1717	  return 0;
1718	}
1719      else if (TREE_CODE (newdecl) == TYPE_DECL
1720               && (DECL_IN_SYSTEM_HEADER (olddecl)
1721                   || DECL_IN_SYSTEM_HEADER (newdecl)))
1722	{
1723	  warning_with_decl (newdecl, "redefinition of `%s'");
1724	  warning_with_decl
1725	    (olddecl,
1726	     ((DECL_INITIAL (olddecl)
1727	       && current_binding_level == global_binding_level)
1728	      ? "`%s' previously defined here"
1729	      : "`%s' previously declared here"));
1730	}
1731      else if (TREE_CODE (olddecl) == FUNCTION_DECL
1732	       && DECL_INITIAL (olddecl) != 0
1733	       && TYPE_ARG_TYPES (oldtype) == 0
1734	       && TYPE_ARG_TYPES (newtype) != 0
1735	       && TYPE_ACTUAL_ARG_TYPES (oldtype) != 0)
1736	{
1737	  tree type, parm;
1738	  int nargs;
1739	  /* Prototype decl follows defn w/o prototype.  */
1740
1741	  for (parm = TYPE_ACTUAL_ARG_TYPES (oldtype),
1742	       type = TYPE_ARG_TYPES (newtype),
1743	       nargs = 1;
1744	       ;
1745	       parm = TREE_CHAIN (parm), type = TREE_CHAIN (type), nargs++)
1746	    {
1747	      if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
1748		  && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
1749		{
1750		  warning_with_decl (newdecl, "prototype for `%s' follows");
1751		  warning_with_decl (olddecl, "non-prototype definition here");
1752		  break;
1753		}
1754	      if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
1755		  || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
1756		{
1757		  error_with_decl (newdecl,
1758				   "prototype for `%s' follows and number of arguments doesn't match");
1759		  error_with_decl (olddecl, "non-prototype definition here");
1760		  errmsg = 1;
1761		  break;
1762		}
1763	      /* Type for passing arg must be consistent
1764		 with that declared for the arg.  */
1765	      if (! comptypes (TREE_VALUE (parm), TREE_VALUE (type))
1766		  /* If -traditional, allow `unsigned int' instead of `int'
1767		     in the prototype.  */
1768		  && (! (flag_traditional
1769			 && TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == integer_type_node
1770			 && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == unsigned_type_node)))
1771		{
1772		  error_with_decl (newdecl,
1773				   "prototype for `%s' follows and argument %d doesn't match",
1774				   nargs);
1775		  error_with_decl (olddecl, "non-prototype definition here");
1776		  errmsg = 1;
1777		  break;
1778		}
1779	    }
1780	}
1781      /* Warn about mismatches in various flags.  */
1782      else
1783	{
1784	  /* Warn if function is now inline
1785	     but was previously declared not inline and has been called.  */
1786	  if (TREE_CODE (olddecl) == FUNCTION_DECL
1787	      && ! DECL_DECLARED_INLINE_P (olddecl)
1788	      && DECL_DECLARED_INLINE_P (newdecl)
1789	      && TREE_USED (olddecl))
1790	    warning_with_decl (newdecl,
1791			       "`%s' declared inline after being called");
1792	  if (TREE_CODE (olddecl) == FUNCTION_DECL
1793	      && ! DECL_DECLARED_INLINE_P (olddecl)
1794	      && DECL_DECLARED_INLINE_P (newdecl)
1795	      && DECL_INITIAL (olddecl) != 0)
1796	    warning_with_decl (newdecl,
1797			       "`%s' declared inline after its definition");
1798
1799	  /* If pedantic, warn when static declaration follows a non-static
1800	     declaration.  Otherwise, do so only for functions.  */
1801	  if ((pedantic || TREE_CODE (olddecl) == FUNCTION_DECL)
1802	      && TREE_PUBLIC (olddecl)
1803	      && !TREE_PUBLIC (newdecl))
1804	    warning_with_decl (newdecl, "static declaration for `%s' follows non-static");
1805
1806	  /* If warn_traditional, warn when a non-static function
1807	     declaration follows a static one.  */
1808	  if (warn_traditional && !in_system_header
1809	      && TREE_CODE (olddecl) == FUNCTION_DECL
1810	      && !TREE_PUBLIC (olddecl)
1811	      && TREE_PUBLIC (newdecl))
1812	    warning_with_decl (newdecl, "non-static declaration for `%s' follows static");
1813
1814	  /* Warn when const declaration follows a non-const
1815	     declaration, but not for functions.  */
1816	  if (TREE_CODE (olddecl) != FUNCTION_DECL
1817	      && !TREE_READONLY (olddecl)
1818	      && TREE_READONLY (newdecl))
1819	    warning_with_decl (newdecl, "const declaration for `%s' follows non-const");
1820	  /* These bits are logically part of the type, for variables.
1821	     But not for functions
1822	     (where qualifiers are not valid ANSI anyway).  */
1823	  else if (pedantic && TREE_CODE (olddecl) != FUNCTION_DECL
1824	      && (TREE_READONLY (newdecl) != TREE_READONLY (olddecl)
1825		  || TREE_THIS_VOLATILE (newdecl) != TREE_THIS_VOLATILE (olddecl)))
1826	    pedwarn_with_decl (newdecl, "type qualifiers for `%s' conflict with previous decl");
1827	}
1828    }
1829
1830  /* Optionally warn about more than one declaration for the same name.  */
1831  if (errmsg == 0 && warn_redundant_decls && DECL_SOURCE_LINE (olddecl) != 0
1832      /* Don't warn about a function declaration
1833	 followed by a definition.  */
1834      && !(TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl) != 0
1835	   && DECL_INITIAL (olddecl) == 0)
1836      /* Don't warn about extern decl followed by (tentative) definition.  */
1837      && !(DECL_EXTERNAL (olddecl) && ! DECL_EXTERNAL (newdecl)))
1838    {
1839      warning_with_decl (newdecl, "redundant redeclaration of `%s' in same scope");
1840      warning_with_decl (olddecl, "previous declaration of `%s'");
1841    }
1842
1843  /* Copy all the DECL_... slots specified in the new decl
1844     except for any that we copy here from the old type.
1845
1846     Past this point, we don't change OLDTYPE and NEWTYPE
1847     even if we change the types of NEWDECL and OLDDECL.  */
1848
1849  if (types_match)
1850    {
1851      /* When copying info to olddecl, we store into write_olddecl
1852	 instead.  This allows us to avoid modifying olddecl when
1853	 different_binding_level is true.  */
1854      tree write_olddecl = different_binding_level ? newdecl : olddecl;
1855
1856      /* Merge the data types specified in the two decls.  */
1857      if (TREE_CODE (newdecl) != FUNCTION_DECL || !DECL_BUILT_IN (olddecl))
1858	{
1859	  if (different_binding_level)
1860	    {
1861	      if (TYPE_ARG_TYPES (oldtype) != 0
1862		  && TYPE_ARG_TYPES (newtype) == 0)
1863		TREE_TYPE (newdecl) = common_type (newtype, oldtype);
1864	      else
1865		TREE_TYPE (newdecl)
1866		  = build_type_attribute_variant
1867		    (newtype,
1868		     merge_attributes (TYPE_ATTRIBUTES (newtype),
1869				       TYPE_ATTRIBUTES (oldtype)));
1870	    }
1871	  else
1872	    TREE_TYPE (newdecl)
1873	      = TREE_TYPE (olddecl)
1874		= common_type (newtype, oldtype);
1875	}
1876
1877      /* Lay the type out, unless already done.  */
1878      if (oldtype != TREE_TYPE (newdecl))
1879	{
1880	  if (TREE_TYPE (newdecl) != error_mark_node)
1881	    layout_type (TREE_TYPE (newdecl));
1882	  if (TREE_CODE (newdecl) != FUNCTION_DECL
1883	      && TREE_CODE (newdecl) != TYPE_DECL
1884	      && TREE_CODE (newdecl) != CONST_DECL)
1885	    layout_decl (newdecl, 0);
1886	}
1887      else
1888	{
1889	  /* Since the type is OLDDECL's, make OLDDECL's size go with.  */
1890	  DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
1891	  DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
1892	  DECL_MODE (newdecl) = DECL_MODE (olddecl);
1893	  if (TREE_CODE (olddecl) != FUNCTION_DECL)
1894	    if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
1895	      {
1896		DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
1897		DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
1898	      }
1899	}
1900
1901      /* Keep the old rtl since we can safely use it.  */
1902      COPY_DECL_RTL (olddecl, newdecl);
1903
1904      /* Merge the type qualifiers.  */
1905      if (TREE_CODE (olddecl) == FUNCTION_DECL
1906	  && DECL_BUILT_IN_NONANSI (olddecl) && TREE_THIS_VOLATILE (olddecl)
1907	  && ! TREE_THIS_VOLATILE (newdecl))
1908	TREE_THIS_VOLATILE (write_olddecl) = 0;
1909
1910      if (TREE_READONLY (newdecl))
1911	TREE_READONLY (write_olddecl) = 1;
1912
1913      if (TREE_THIS_VOLATILE (newdecl))
1914	{
1915	  TREE_THIS_VOLATILE (write_olddecl) = 1;
1916	  if (TREE_CODE (newdecl) == VAR_DECL
1917	      /* If an automatic variable is re-declared in the same
1918		 function scope, but the old declaration was not
1919		 volatile, make_var_volatile() would crash because the
1920		 variable would have been assigned to a pseudo, not a
1921		 MEM.  Since this duplicate declaration is invalid
1922		 anyway, we just skip the call.  */
1923	      && errmsg == 0)
1924	    make_var_volatile (newdecl);
1925	}
1926
1927      /* Keep source location of definition rather than declaration.  */
1928      /* When called with different_binding_level set, keep the old
1929	 information so that meaningful diagnostics can be given.  */
1930      if (DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0
1931	  && ! different_binding_level)
1932	{
1933	  DECL_SOURCE_LINE (newdecl) = DECL_SOURCE_LINE (olddecl);
1934	  DECL_SOURCE_FILE (newdecl) = DECL_SOURCE_FILE (olddecl);
1935	}
1936
1937      /* Merge the unused-warning information.  */
1938      if (DECL_IN_SYSTEM_HEADER (olddecl))
1939	DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1940      else if (DECL_IN_SYSTEM_HEADER (newdecl))
1941	DECL_IN_SYSTEM_HEADER (write_olddecl) = 1;
1942
1943      /* Merge the initialization information.  */
1944      /* When called with different_binding_level set, don't copy over
1945	 DECL_INITIAL, so that we don't accidentally change function
1946	 declarations into function definitions.  */
1947      if (DECL_INITIAL (newdecl) == 0 && ! different_binding_level)
1948	DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1949
1950      /* Merge the section attribute.
1951         We want to issue an error if the sections conflict but that must be
1952	 done later in decl_attributes since we are called before attributes
1953	 are assigned.  */
1954      if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
1955	DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
1956
1957      /* Copy the assembler name.
1958	 Currently, it can only be defined in the prototype.  */
1959      COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
1960
1961      if (TREE_CODE (newdecl) == FUNCTION_DECL)
1962	{
1963	  DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
1964	  DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1965	  DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
1966	  DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
1967	    |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
1968	}
1969    }
1970  /* If cannot merge, then use the new type and qualifiers,
1971     and don't preserve the old rtl.  */
1972  else if (! different_binding_level)
1973    {
1974      TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
1975      TREE_READONLY (olddecl) = TREE_READONLY (newdecl);
1976      TREE_THIS_VOLATILE (olddecl) = TREE_THIS_VOLATILE (newdecl);
1977      TREE_SIDE_EFFECTS (olddecl) = TREE_SIDE_EFFECTS (newdecl);
1978    }
1979
1980  /* Merge the storage class information.  */
1981  merge_weak (newdecl, olddecl);
1982
1983  /* For functions, static overrides non-static.  */
1984  if (TREE_CODE (newdecl) == FUNCTION_DECL)
1985    {
1986      TREE_PUBLIC (newdecl) &= TREE_PUBLIC (olddecl);
1987      /* This is since we don't automatically
1988	 copy the attributes of NEWDECL into OLDDECL.  */
1989      /* No need to worry about different_binding_level here because
1990	 then TREE_PUBLIC (newdecl) was true.  */
1991      TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1992      /* If this clears `static', clear it in the identifier too.  */
1993      if (! TREE_PUBLIC (olddecl))
1994	TREE_PUBLIC (DECL_NAME (olddecl)) = 0;
1995    }
1996  if (DECL_EXTERNAL (newdecl))
1997    {
1998      if (! different_binding_level)
1999	{
2000	  /* Don't mess with these flags on local externs; they remain
2001	     external even if there's a declaration at file scope which
2002	     isn't.  */
2003	  TREE_STATIC (newdecl) = TREE_STATIC (olddecl);
2004	  DECL_EXTERNAL (newdecl) = DECL_EXTERNAL (olddecl);
2005	}
2006      /* An extern decl does not override previous storage class.  */
2007      TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
2008      if (! DECL_EXTERNAL (newdecl))
2009	DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
2010    }
2011  else
2012    {
2013      TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
2014      TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
2015    }
2016
2017  if (TREE_CODE (newdecl) == FUNCTION_DECL)
2018    {
2019      /* If we're redefining a function previously defined as extern
2020	 inline, make sure we emit debug info for the inline before we
2021	 throw it away, in case it was inlined into a function that hasn't
2022	 been written out yet.  */
2023      if (new_is_definition && DECL_INITIAL (olddecl) && TREE_USED (olddecl))
2024	{
2025	  (*debug_hooks->outlining_inline_function) (olddecl);
2026
2027	  /* The new defn must not be inline.  */
2028	  DECL_INLINE (newdecl) = 0;
2029	  DECL_UNINLINABLE (newdecl) = 1;
2030	}
2031      else
2032	{
2033	  /* If either decl says `inline', this fn is inline,
2034	     unless its definition was passed already.  */
2035	  if (DECL_DECLARED_INLINE_P (newdecl)
2036	      || DECL_DECLARED_INLINE_P (olddecl))
2037	    DECL_DECLARED_INLINE_P (newdecl) = 1;
2038
2039	  DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
2040	    = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
2041	}
2042
2043      if (DECL_BUILT_IN (olddecl))
2044	{
2045	  /* Get rid of any built-in function if new arg types don't match it
2046	     or if we have a function definition.  */
2047	  if (! types_match || new_is_definition)
2048	    {
2049	      if (! different_binding_level)
2050		{
2051		  TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
2052		  DECL_BUILT_IN_CLASS (olddecl) = NOT_BUILT_IN;
2053		}
2054	    }
2055	  else
2056	    {
2057	      /* If redeclaring a builtin function, and not a definition,
2058		 it stays built in.  */
2059	      DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
2060	      DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
2061	    }
2062	}
2063
2064      /* Also preserve various other info from the definition.  */
2065      if (! new_is_definition)
2066	{
2067	  DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
2068	  /* When called with different_binding_level set, don't copy over
2069	     DECL_INITIAL, so that we don't accidentally change function
2070	     declarations into function definitions.  */
2071	  if (! different_binding_level)
2072	    DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
2073	  DECL_SAVED_INSNS (newdecl) = DECL_SAVED_INSNS (olddecl);
2074	  DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
2075	  DECL_NUM_STMTS (newdecl) = DECL_NUM_STMTS (olddecl);
2076	  DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
2077
2078	  /* Set DECL_INLINE on the declaration if we've got a body
2079	     from which to instantiate.  */
2080	  if (DECL_INLINE (olddecl) && ! DECL_UNINLINABLE (newdecl))
2081	    {
2082	      DECL_INLINE (newdecl) = 1;
2083	      DECL_ABSTRACT_ORIGIN (newdecl)
2084		= (different_binding_level
2085		   ? DECL_ORIGIN (olddecl)
2086		   : DECL_ABSTRACT_ORIGIN (olddecl));
2087	    }
2088	}
2089      else
2090	{
2091	  /* If a previous declaration said inline, mark the
2092	     definition as inlinable.  */
2093	  if (DECL_DECLARED_INLINE_P (newdecl)
2094	      && ! DECL_UNINLINABLE (newdecl))
2095	    DECL_INLINE (newdecl) = 1;
2096	}
2097    }
2098  if (different_binding_level)
2099    return 0;
2100
2101  /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
2102     But preserve OLDDECL's DECL_UID.  */
2103  {
2104    unsigned olddecl_uid = DECL_UID (olddecl);
2105
2106    memcpy ((char *) olddecl + sizeof (struct tree_common),
2107	    (char *) newdecl + sizeof (struct tree_common),
2108	    sizeof (struct tree_decl) - sizeof (struct tree_common));
2109    DECL_UID (olddecl) = olddecl_uid;
2110  }
2111
2112  /* NEWDECL contains the merged attribute lists.
2113     Update OLDDECL to be the same.  */
2114  DECL_ATTRIBUTES (olddecl) = DECL_ATTRIBUTES (newdecl);
2115
2116  return 1;
2117}
2118
2119/* Check whether decl-node X shadows an existing declaration.
2120   OLDLOCAL is the old IDENTIFIER_LOCAL_VALUE of the DECL_NAME of X,
2121   which might be a NULL_TREE.  */
2122static void
2123warn_if_shadowing (x, oldlocal)
2124     tree x, oldlocal;
2125{
2126  tree name;
2127
2128  if (DECL_EXTERNAL (x))
2129    return;
2130
2131  name = DECL_NAME (x);
2132
2133  /* Warn if shadowing an argument at the top level of the body.  */
2134  if (oldlocal != 0
2135      /* This warning doesn't apply to the parms of a nested fcn.  */
2136      && ! current_binding_level->parm_flag
2137      /* Check that this is one level down from the parms.  */
2138      && current_binding_level->level_chain->parm_flag
2139      /* Check that the decl being shadowed
2140	 comes from the parm level, one level up.  */
2141      && chain_member (oldlocal, current_binding_level->level_chain->names))
2142    {
2143      if (TREE_CODE (oldlocal) == PARM_DECL)
2144	pedwarn ("declaration of `%s' shadows a parameter",
2145		 IDENTIFIER_POINTER (name));
2146      else
2147	pedwarn ("declaration of `%s' shadows a symbol from the parameter list",
2148		 IDENTIFIER_POINTER (name));
2149    }
2150  /* Maybe warn if shadowing something else.  */
2151  else if (warn_shadow
2152	   /* No shadow warnings for internally generated vars.  */
2153	   && DECL_SOURCE_LINE (x) != 0
2154	   /* No shadow warnings for vars made for inlining.  */
2155	   && ! DECL_FROM_INLINE (x))
2156    {
2157      if (TREE_CODE (x) == PARM_DECL
2158	  && current_binding_level->level_chain->parm_flag)
2159	/* Don't warn about the parm names in function declarator
2160	   within a function declarator.
2161	   It would be nice to avoid warning in any function
2162	   declarator in a declaration, as opposed to a definition,
2163	   but there is no way to tell it's not a definition.  */
2164	;
2165      else if (oldlocal)
2166	{
2167	  if (TREE_CODE (oldlocal) == PARM_DECL)
2168	    shadow_warning ("a parameter", name, oldlocal);
2169	  else
2170	    shadow_warning ("a previous local", name, oldlocal);
2171	}
2172      else if (IDENTIFIER_GLOBAL_VALUE (name) != 0
2173	       && IDENTIFIER_GLOBAL_VALUE (name) != error_mark_node)
2174	shadow_warning ("a global declaration", name,
2175			IDENTIFIER_GLOBAL_VALUE (name));
2176    }
2177}
2178
2179/* Record a decl-node X as belonging to the current lexical scope.
2180   Check for errors (such as an incompatible declaration for the same
2181   name already seen in the same scope).
2182
2183   Returns either X or an old decl for the same name.
2184   If an old decl is returned, it may have been smashed
2185   to agree with what X says.  */
2186
2187tree
2188pushdecl (x)
2189     tree x;
2190{
2191  tree t;
2192  tree name = DECL_NAME (x);
2193  struct binding_level *b = current_binding_level;
2194
2195  /* Functions need the lang_decl data.  */
2196  if (TREE_CODE (x) == FUNCTION_DECL && ! DECL_LANG_SPECIFIC (x))
2197    DECL_LANG_SPECIFIC (x) = (struct lang_decl *)
2198      ggc_alloc_cleared (sizeof (struct lang_decl));
2199
2200  DECL_CONTEXT (x) = current_function_decl;
2201  /* A local extern declaration for a function doesn't constitute nesting.
2202     A local auto declaration does, since it's a forward decl
2203     for a nested function coming later.  */
2204  if ((TREE_CODE (x) == FUNCTION_DECL || TREE_CODE (x) == VAR_DECL)
2205      && DECL_INITIAL (x) == 0 && DECL_EXTERNAL (x))
2206    DECL_CONTEXT (x) = 0;
2207
2208  if (name)
2209    {
2210      int different_binding_level = 0;
2211
2212      if (warn_nested_externs
2213	  && DECL_EXTERNAL (x)
2214	  && b != global_binding_level
2215	  && x != IDENTIFIER_IMPLICIT_DECL (name)
2216	  /* No error messages for __FUNCTION__ and __PRETTY_FUNCTION__.  */
2217	  && !DECL_IN_SYSTEM_HEADER (x))
2218	warning ("nested extern declaration of `%s'",
2219		 IDENTIFIER_POINTER (name));
2220
2221      t = lookup_name_current_level (name);
2222      /* Don't type check externs here when -traditional.  This is so that
2223	 code with conflicting declarations inside blocks will get warnings
2224	 not errors.  X11 for instance depends on this.  */
2225      if (! t && DECL_EXTERNAL (x) && TREE_PUBLIC (x) && ! flag_traditional)
2226	{
2227	  t = IDENTIFIER_GLOBAL_VALUE (name);
2228	  /* Type decls at global scope don't conflict with externs declared
2229	     inside lexical blocks.  */
2230	  if (! t || TREE_CODE (t) == TYPE_DECL)
2231	    /* If there's no visible global declaration, try for an
2232               invisible one.  */
2233	    t = IDENTIFIER_LIMBO_VALUE (name);
2234	  different_binding_level = 1;
2235	}
2236      if (t != 0 && t == error_mark_node)
2237	/* error_mark_node is 0 for a while during initialization!  */
2238	{
2239	  t = 0;
2240	  error_with_decl (x, "`%s' used prior to declaration");
2241	}
2242
2243      /* If this decl is `static' and an implicit decl was seen previously,
2244	 warn.  But don't complain if -traditional,
2245	 since traditional compilers don't complain.  */
2246      if (! flag_traditional && TREE_PUBLIC (name)
2247	  /* Don't test for DECL_EXTERNAL, because grokdeclarator
2248	     sets this for all functions.  */
2249	  && ! TREE_PUBLIC (x)
2250	  && (TREE_CODE (x) == FUNCTION_DECL || b == global_binding_level)
2251	  /* We used to warn also for explicit extern followed by static,
2252	     but sometimes you need to do it that way.  */
2253	  && IDENTIFIER_IMPLICIT_DECL (name) != 0)
2254	{
2255	  pedwarn ("`%s' was declared implicitly `extern' and later `static'",
2256		   IDENTIFIER_POINTER (name));
2257	  pedwarn_with_file_and_line
2258	    (DECL_SOURCE_FILE (IDENTIFIER_IMPLICIT_DECL (name)),
2259	     DECL_SOURCE_LINE (IDENTIFIER_IMPLICIT_DECL (name)),
2260	     "previous declaration of `%s'",
2261	     IDENTIFIER_POINTER (name));
2262	  TREE_THIS_VOLATILE (name) = 1;
2263	}
2264
2265      if (t != 0 && duplicate_decls (x, t, different_binding_level))
2266	{
2267	  if (TREE_CODE (t) == PARM_DECL)
2268	    {
2269	      /* Don't allow more than one "real" duplicate
2270		 of a forward parm decl.  */
2271	      TREE_ASM_WRITTEN (t) = TREE_ASM_WRITTEN (x);
2272	      return t;
2273	    }
2274	  return t;
2275	}
2276
2277      /* If we are processing a typedef statement, generate a whole new
2278	 ..._TYPE node (which will be just an variant of the existing
2279	 ..._TYPE node with identical properties) and then install the
2280	 TYPE_DECL node generated to represent the typedef name as the
2281	 TYPE_NAME of this brand new (duplicate) ..._TYPE node.
2282
2283	 The whole point here is to end up with a situation where each
2284	 and every ..._TYPE node the compiler creates will be uniquely
2285	 associated with AT MOST one node representing a typedef name.
2286	 This way, even though the compiler substitutes corresponding
2287	 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
2288	 early on, later parts of the compiler can always do the reverse
2289	 translation and get back the corresponding typedef name.  For
2290	 example, given:
2291
2292		typedef struct S MY_TYPE;
2293		MY_TYPE object;
2294
2295	 Later parts of the compiler might only know that `object' was of
2296	 type `struct S' if it were not for code just below.  With this
2297	 code however, later parts of the compiler see something like:
2298
2299		struct S' == struct S
2300		typedef struct S' MY_TYPE;
2301		struct S' object;
2302
2303	 And they can then deduce (from the node for type struct S') that
2304	 the original object declaration was:
2305
2306		MY_TYPE object;
2307
2308	 Being able to do this is important for proper support of protoize,
2309	 and also for generating precise symbolic debugging information
2310	 which takes full account of the programmer's (typedef) vocabulary.
2311
2312         Obviously, we don't want to generate a duplicate ..._TYPE node if
2313	 the TYPE_DECL node that we are now processing really represents a
2314	 standard built-in type.
2315
2316         Since all standard types are effectively declared at line zero
2317         in the source file, we can easily check to see if we are working
2318         on a standard type by checking the current value of lineno.  */
2319
2320      if (TREE_CODE (x) == TYPE_DECL)
2321	{
2322	  if (DECL_SOURCE_LINE (x) == 0)
2323	    {
2324	      if (TYPE_NAME (TREE_TYPE (x)) == 0)
2325		TYPE_NAME (TREE_TYPE (x)) = x;
2326	    }
2327	  else if (TREE_TYPE (x) != error_mark_node
2328		   && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
2329	    {
2330	      tree tt = TREE_TYPE (x);
2331	      DECL_ORIGINAL_TYPE (x) = tt;
2332	      tt = build_type_copy (tt);
2333	      TYPE_NAME (tt) = x;
2334	      TREE_USED (tt) = TREE_USED (x);
2335	      TREE_TYPE (x) = tt;
2336	    }
2337	}
2338
2339      /* Multiple external decls of the same identifier ought to match.
2340	 Check against both global declarations (when traditional) and out of
2341	 scope (limbo) block level declarations.
2342
2343	 We get warnings about inline functions where they are defined.
2344	 Avoid duplicate warnings where they are used.  */
2345      if (TREE_PUBLIC (x)
2346	  && ! (TREE_CODE (x) == FUNCTION_DECL && DECL_INLINE (x)))
2347	{
2348	  tree decl;
2349
2350	  if (flag_traditional && IDENTIFIER_GLOBAL_VALUE (name) != 0
2351	      && (DECL_EXTERNAL (IDENTIFIER_GLOBAL_VALUE (name))
2352		  || TREE_PUBLIC (IDENTIFIER_GLOBAL_VALUE (name))))
2353	    decl = IDENTIFIER_GLOBAL_VALUE (name);
2354	  else if (IDENTIFIER_LIMBO_VALUE (name) != 0)
2355	    /* Decls in limbo are always extern, so no need to check that.  */
2356	    decl = IDENTIFIER_LIMBO_VALUE (name);
2357	  else
2358	    decl = 0;
2359
2360	  if (decl && ! comptypes (TREE_TYPE (x), TREE_TYPE (decl))
2361	      /* If old decl is built-in, we already warned if we should.  */
2362	      && !DECL_BUILT_IN (decl))
2363	    {
2364	      pedwarn_with_decl (x,
2365				 "type mismatch with previous external decl");
2366	      pedwarn_with_decl (decl, "previous external decl of `%s'");
2367	    }
2368	}
2369
2370      /* If a function has had an implicit declaration, and then is defined,
2371	 make sure they are compatible.  */
2372
2373      if (IDENTIFIER_IMPLICIT_DECL (name) != 0
2374	  && IDENTIFIER_GLOBAL_VALUE (name) == 0
2375	  && TREE_CODE (x) == FUNCTION_DECL
2376	  && ! comptypes (TREE_TYPE (x),
2377			  TREE_TYPE (IDENTIFIER_IMPLICIT_DECL (name))))
2378	{
2379	  warning_with_decl (x, "type mismatch with previous implicit declaration");
2380	  warning_with_decl (IDENTIFIER_IMPLICIT_DECL (name),
2381			     "previous implicit declaration of `%s'");
2382	}
2383
2384      /* In PCC-compatibility mode, extern decls of vars with no current decl
2385	 take effect at top level no matter where they are.  */
2386      if (flag_traditional && DECL_EXTERNAL (x)
2387	  && lookup_name (name) == 0)
2388	{
2389	  tree type = TREE_TYPE (x);
2390
2391	  /* But don't do this if the type contains temporary nodes.  */
2392	  while (type)
2393	    {
2394	      if (type == error_mark_node)
2395		break;
2396	      if (TYPE_CONTEXT (type))
2397		{
2398		  warning_with_decl (x, "type of external `%s' is not global");
2399		  /* By exiting the loop early, we leave TYPE nonzero,
2400		     and thus prevent globalization of the decl.  */
2401		  break;
2402		}
2403	      else if (TREE_CODE (type) == FUNCTION_TYPE
2404		       && TYPE_ARG_TYPES (type) != 0)
2405		/* The types might not be truly local,
2406		   but the list of arg types certainly is temporary.
2407		   Since prototypes are nontraditional,
2408		   ok not to do the traditional thing.  */
2409		break;
2410	      type = TREE_TYPE (type);
2411	    }
2412
2413	  if (type == 0)
2414	    b = global_binding_level;
2415	}
2416
2417      /* This name is new in its binding level.
2418	 Install the new declaration and return it.  */
2419      if (b == global_binding_level)
2420	{
2421	  /* Install a global value.  */
2422
2423	  /* If the first global decl has external linkage,
2424	     warn if we later see static one.  */
2425	  if (IDENTIFIER_GLOBAL_VALUE (name) == 0 && TREE_PUBLIC (x))
2426	    TREE_PUBLIC (name) = 1;
2427
2428	  IDENTIFIER_GLOBAL_VALUE (name) = x;
2429
2430	  /* We no longer care about any previous block level declarations.  */
2431	  IDENTIFIER_LIMBO_VALUE (name) = 0;
2432
2433	  /* Don't forget if the function was used via an implicit decl.  */
2434	  if (IDENTIFIER_IMPLICIT_DECL (name)
2435	      && TREE_USED (IDENTIFIER_IMPLICIT_DECL (name)))
2436	    TREE_USED (x) = 1, TREE_USED (name) = 1;
2437
2438	  /* Don't forget if its address was taken in that way.  */
2439	  if (IDENTIFIER_IMPLICIT_DECL (name)
2440	      && TREE_ADDRESSABLE (IDENTIFIER_IMPLICIT_DECL (name)))
2441	    TREE_ADDRESSABLE (x) = 1;
2442
2443	  /* Warn about mismatches against previous implicit decl.  */
2444	  if (IDENTIFIER_IMPLICIT_DECL (name) != 0
2445	      /* If this real decl matches the implicit, don't complain.  */
2446	      && ! (TREE_CODE (x) == FUNCTION_DECL
2447		    && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (x)))
2448			== integer_type_node)))
2449	    pedwarn ("`%s' was previously implicitly declared to return `int'",
2450		     IDENTIFIER_POINTER (name));
2451
2452	  /* If this decl is `static' and an `extern' was seen previously,
2453	     that is erroneous.  */
2454	  if (TREE_PUBLIC (name)
2455	      && ! TREE_PUBLIC (x) && ! DECL_EXTERNAL (x))
2456	    {
2457	      /* Okay to redeclare an ANSI built-in as static.  */
2458	      if (t != 0 && DECL_BUILT_IN (t))
2459		;
2460	      /* Okay to declare a non-ANSI built-in as anything.  */
2461	      else if (t != 0 && DECL_BUILT_IN_NONANSI (t))
2462		;
2463	      /* Okay to have global type decl after an earlier extern
2464		 declaration inside a lexical block.  */
2465	      else if (TREE_CODE (x) == TYPE_DECL)
2466		;
2467	      else if (IDENTIFIER_IMPLICIT_DECL (name))
2468		{
2469		  if (! TREE_THIS_VOLATILE (name))
2470		    pedwarn ("`%s' was declared implicitly `extern' and later `static'",
2471			     IDENTIFIER_POINTER (name));
2472		}
2473	      else
2474		pedwarn ("`%s' was declared `extern' and later `static'",
2475			 IDENTIFIER_POINTER (name));
2476	    }
2477	}
2478      else
2479	{
2480	  /* Here to install a non-global value.  */
2481	  tree oldlocal = IDENTIFIER_LOCAL_VALUE (name);
2482	  tree oldglobal = IDENTIFIER_GLOBAL_VALUE (name);
2483
2484	  IDENTIFIER_LOCAL_VALUE (name) = x;
2485
2486	  /* If this is an extern function declaration, see if we
2487	     have a global definition or declaration for the function.  */
2488	  if (oldlocal == 0
2489	      && oldglobal != 0
2490	      && TREE_CODE (x) == FUNCTION_DECL
2491	      && TREE_CODE (oldglobal) == FUNCTION_DECL
2492	      && DECL_EXTERNAL (x)
2493	      && ! DECL_DECLARED_INLINE_P (x))
2494	    {
2495	      /* We have one.  Their types must agree.  */
2496	      if (! comptypes (TREE_TYPE (x),
2497			       TREE_TYPE (IDENTIFIER_GLOBAL_VALUE (name))))
2498		pedwarn_with_decl (x, "extern declaration of `%s' doesn't match global one");
2499	      else
2500		{
2501		  /* Inner extern decl is inline if global one is.
2502		     Copy enough to really inline it.  */
2503		  if (DECL_DECLARED_INLINE_P (oldglobal))
2504		    {
2505		      DECL_DECLARED_INLINE_P (x)
2506		        = DECL_DECLARED_INLINE_P (oldglobal);
2507		      DECL_INLINE (x) = DECL_INLINE (oldglobal);
2508		      DECL_INITIAL (x) = (current_function_decl == oldglobal
2509					  ? 0 : DECL_INITIAL (oldglobal));
2510		      DECL_SAVED_INSNS (x) = DECL_SAVED_INSNS (oldglobal);
2511		      DECL_NUM_STMTS (x) = DECL_NUM_STMTS (oldglobal);
2512		      DECL_ARGUMENTS (x) = DECL_ARGUMENTS (oldglobal);
2513		      DECL_RESULT (x) = DECL_RESULT (oldglobal);
2514		      TREE_ASM_WRITTEN (x) = TREE_ASM_WRITTEN (oldglobal);
2515		      DECL_ABSTRACT_ORIGIN (x)
2516			= DECL_ABSTRACT_ORIGIN (oldglobal);
2517		    }
2518		  /* Inner extern decl is built-in if global one is.  */
2519		  if (DECL_BUILT_IN (oldglobal))
2520		    {
2521		      DECL_BUILT_IN_CLASS (x) = DECL_BUILT_IN_CLASS (oldglobal);
2522		      DECL_FUNCTION_CODE (x) = DECL_FUNCTION_CODE (oldglobal);
2523		    }
2524		  /* Keep the arg types from a file-scope fcn defn.  */
2525		  if (TYPE_ARG_TYPES (TREE_TYPE (oldglobal)) != 0
2526		      && DECL_INITIAL (oldglobal)
2527		      && TYPE_ARG_TYPES (TREE_TYPE (x)) == 0)
2528		    TREE_TYPE (x) = TREE_TYPE (oldglobal);
2529		}
2530	    }
2531
2532#if 0
2533	  /* This case is probably sometimes the right thing to do.  */
2534	  /* If we have a local external declaration,
2535	     then any file-scope declaration should not
2536	     have been static.  */
2537	  if (oldlocal == 0 && oldglobal != 0
2538	      && !TREE_PUBLIC (oldglobal)
2539	      && DECL_EXTERNAL (x) && TREE_PUBLIC (x))
2540	    warning ("`%s' locally external but globally static",
2541		     IDENTIFIER_POINTER (name));
2542#endif
2543
2544	  /* If we have a local external declaration,
2545	     and no file-scope declaration has yet been seen,
2546	     then if we later have a file-scope decl it must not be static.  */
2547	  if (oldlocal == 0
2548	      && DECL_EXTERNAL (x)
2549	      && TREE_PUBLIC (x))
2550	    {
2551	      if (oldglobal == 0)
2552		TREE_PUBLIC (name) = 1;
2553
2554	      /* Save this decl, so that we can do type checking against
2555		 other decls after it falls out of scope.
2556
2557		 Only save it once.  This prevents temporary decls created in
2558		 expand_inline_function from being used here, since this
2559		 will have been set when the inline function was parsed.
2560		 It also helps give slightly better warnings.  */
2561	      if (IDENTIFIER_LIMBO_VALUE (name) == 0)
2562		IDENTIFIER_LIMBO_VALUE (name) = x;
2563	    }
2564
2565	  warn_if_shadowing (x, oldlocal);
2566
2567	  /* If storing a local value, there may already be one (inherited).
2568	     If so, record it for restoration when this binding level ends.  */
2569	  if (oldlocal != 0)
2570	    b->shadowed = tree_cons (name, oldlocal, b->shadowed);
2571	}
2572
2573      /* Keep count of variables in this level with incomplete type.
2574	 If the input is erroneous, we can have error_mark in the type
2575	 slot (e.g. "f(void a, ...)") - that doesn't count as an
2576	 incomplete type.  */
2577      if (TREE_TYPE (x) != error_mark_node
2578	  && !COMPLETE_TYPE_P (TREE_TYPE (x)))
2579	{
2580	  tree element = TREE_TYPE (x);
2581
2582	  while (TREE_CODE (element) == ARRAY_TYPE)
2583	    element = TREE_TYPE (element);
2584	  if (TREE_CODE (element) == RECORD_TYPE
2585	      || TREE_CODE (element) == UNION_TYPE)
2586	    ++b->n_incomplete;
2587	}
2588    }
2589
2590  /* Put decls on list in reverse order.
2591     We will reverse them later if necessary.  */
2592  TREE_CHAIN (x) = b->names;
2593  b->names = x;
2594
2595  return x;
2596}
2597
2598/* Like pushdecl, only it places X in GLOBAL_BINDING_LEVEL, if appropriate.  */
2599
2600tree
2601pushdecl_top_level (x)
2602     tree x;
2603{
2604  tree t;
2605  struct binding_level *b = current_binding_level;
2606
2607  current_binding_level = global_binding_level;
2608  t = pushdecl (x);
2609  current_binding_level = b;
2610  return t;
2611}
2612
2613/* Generate an implicit declaration for identifier FUNCTIONID
2614   as a function of type int ().  Print a warning if appropriate.  */
2615
2616tree
2617implicitly_declare (functionid)
2618     tree functionid;
2619{
2620  tree decl;
2621  int traditional_warning = 0;
2622  /* Only one "implicit declaration" warning per identifier.  */
2623  int implicit_warning;
2624
2625  /* We used to reuse an old implicit decl here,
2626     but this loses with inline functions because it can clobber
2627     the saved decl chains.  */
2628#if 0
2629  if (IDENTIFIER_IMPLICIT_DECL (functionid) != 0)
2630    decl = IDENTIFIER_IMPLICIT_DECL (functionid);
2631  else
2632#endif
2633    decl = build_decl (FUNCTION_DECL, functionid, default_function_type);
2634
2635  /* Warn of implicit decl following explicit local extern decl.
2636     This is probably a program designed for traditional C.  */
2637  if (TREE_PUBLIC (functionid) && IDENTIFIER_GLOBAL_VALUE (functionid) == 0)
2638    traditional_warning = 1;
2639
2640  /* Warn once of an implicit declaration.  */
2641  implicit_warning = (IDENTIFIER_IMPLICIT_DECL (functionid) == 0);
2642
2643  DECL_EXTERNAL (decl) = 1;
2644  TREE_PUBLIC (decl) = 1;
2645
2646  /* Record that we have an implicit decl and this is it.  */
2647  IDENTIFIER_IMPLICIT_DECL (functionid) = decl;
2648
2649  /* ANSI standard says implicit declarations are in the innermost block.
2650     So we record the decl in the standard fashion.
2651     If flag_traditional is set, pushdecl does it top-level.  */
2652  pushdecl (decl);
2653
2654  /* This is a no-op in c-lang.c or something real in objc-actions.c.  */
2655  maybe_objc_check_decl (decl);
2656
2657  rest_of_decl_compilation (decl, NULL, 0, 0);
2658
2659  if (implicit_warning)
2660    implicit_decl_warning (functionid);
2661  else if (warn_traditional && traditional_warning)
2662    warning ("function `%s' was previously declared within a block",
2663	     IDENTIFIER_POINTER (functionid));
2664
2665  /* Write a record describing this implicit function declaration to the
2666     prototypes file (if requested).  */
2667
2668  gen_aux_info_record (decl, 0, 1, 0);
2669
2670  /* Possibly apply some default attributes to this implicit declaration.  */
2671  decl_attributes (&decl, NULL_TREE, 0);
2672
2673  return decl;
2674}
2675
2676void
2677implicit_decl_warning (id)
2678     tree id;
2679{
2680  const char *name = IDENTIFIER_POINTER (id);
2681  if (mesg_implicit_function_declaration == 2)
2682    error ("implicit declaration of function `%s'", name);
2683  else if (mesg_implicit_function_declaration == 1)
2684    warning ("implicit declaration of function `%s'", name);
2685}
2686
2687/* Return zero if the declaration NEWDECL is valid
2688   when the declaration OLDDECL (assumed to be for the same name)
2689   has already been seen.
2690   Otherwise return 1 if NEWDECL is a redefinition, 2 if it is a redeclaration,
2691   and 3 if it is a conflicting declaration.  */
2692
2693static int
2694redeclaration_error_message (newdecl, olddecl)
2695     tree newdecl, olddecl;
2696{
2697  if (TREE_CODE (newdecl) == TYPE_DECL)
2698    {
2699      if (flag_traditional && TREE_TYPE (newdecl) == TREE_TYPE (olddecl))
2700	return 0;
2701      /* pushdecl creates distinct types for TYPE_DECLs by calling
2702	 build_type_copy, so the above comparison generally fails.  We do
2703	 another test against the TYPE_MAIN_VARIANT of the olddecl, which
2704	 is equivalent to what this code used to do before the build_type_copy
2705	 call.  The variant type distinction should not matter for traditional
2706	 code, because it doesn't have type qualifiers.  */
2707      if (flag_traditional
2708	  && TYPE_MAIN_VARIANT (TREE_TYPE (olddecl)) == TREE_TYPE (newdecl))
2709	return 0;
2710      if (DECL_IN_SYSTEM_HEADER (olddecl) || DECL_IN_SYSTEM_HEADER (newdecl))
2711	return 0;
2712      return 1;
2713    }
2714  else if (TREE_CODE (newdecl) == FUNCTION_DECL)
2715    {
2716      /* Declarations of functions can insist on internal linkage
2717	 but they can't be inconsistent with internal linkage,
2718	 so there can be no error on that account.
2719	 However defining the same name twice is no good.  */
2720      if (DECL_INITIAL (olddecl) != 0 && DECL_INITIAL (newdecl) != 0
2721	  /* However, defining once as extern inline and a second
2722	     time in another way is ok.  */
2723	  && ! (DECL_DECLARED_INLINE_P (olddecl) && DECL_EXTERNAL (olddecl)
2724	       && ! (DECL_DECLARED_INLINE_P (newdecl)
2725		     && DECL_EXTERNAL (newdecl))))
2726	return 1;
2727      return 0;
2728    }
2729  else if (DECL_CONTEXT (newdecl) == NULL_TREE)
2730    {
2731      /* Objects declared at top level:  */
2732      /* If at least one is a reference, it's ok.  */
2733      if (DECL_EXTERNAL (newdecl) || DECL_EXTERNAL (olddecl))
2734	return 0;
2735      /* Reject two definitions.  */
2736      if (DECL_INITIAL (olddecl) != 0 && DECL_INITIAL (newdecl) != 0)
2737	return 1;
2738      /* Now we have two tentative defs, or one tentative and one real def.  */
2739      /* Insist that the linkage match.  */
2740      if (TREE_PUBLIC (olddecl) != TREE_PUBLIC (newdecl))
2741	return 3;
2742      return 0;
2743    }
2744  else if (current_binding_level->parm_flag
2745	   && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
2746    return 0;
2747  else
2748    {
2749      /* Newdecl has block scope.  If olddecl has block scope also, then
2750	 reject two definitions, and reject a definition together with an
2751	 external reference.  Otherwise, it is OK, because newdecl must
2752	 be an extern reference to olddecl.  */
2753      if (!(DECL_EXTERNAL (newdecl) && DECL_EXTERNAL (olddecl))
2754	  && DECL_CONTEXT (newdecl) == DECL_CONTEXT (olddecl))
2755	return 2;
2756      return 0;
2757    }
2758}
2759
2760/* Get the LABEL_DECL corresponding to identifier ID as a label.
2761   Create one if none exists so far for the current function.
2762   This function is called for both label definitions and label references.  */
2763
2764tree
2765lookup_label (id)
2766     tree id;
2767{
2768  tree decl = IDENTIFIER_LABEL_VALUE (id);
2769
2770  if (current_function_decl == 0)
2771    {
2772      error ("label %s referenced outside of any function",
2773	     IDENTIFIER_POINTER (id));
2774      return 0;
2775    }
2776
2777  /* Use a label already defined or ref'd with this name.  */
2778  if (decl != 0)
2779    {
2780      /* But not if it is inherited and wasn't declared to be inheritable.  */
2781      if (DECL_CONTEXT (decl) != current_function_decl
2782	  && ! C_DECLARED_LABEL_FLAG (decl))
2783	return shadow_label (id);
2784      return decl;
2785    }
2786
2787  decl = build_decl (LABEL_DECL, id, void_type_node);
2788
2789  /* A label not explicitly declared must be local to where it's ref'd.  */
2790  DECL_CONTEXT (decl) = current_function_decl;
2791
2792  DECL_MODE (decl) = VOIDmode;
2793
2794  /* Say where one reference is to the label,
2795     for the sake of the error if it is not defined.  */
2796  DECL_SOURCE_LINE (decl) = lineno;
2797  DECL_SOURCE_FILE (decl) = input_filename;
2798
2799  IDENTIFIER_LABEL_VALUE (id) = decl;
2800
2801  named_labels = tree_cons (NULL_TREE, decl, named_labels);
2802
2803  return decl;
2804}
2805
2806/* Make a label named NAME in the current function,
2807   shadowing silently any that may be inherited from containing functions
2808   or containing scopes.
2809
2810   Note that valid use, if the label being shadowed
2811   comes from another scope in the same function,
2812   requires calling declare_nonlocal_label right away.  */
2813
2814tree
2815shadow_label (name)
2816     tree name;
2817{
2818  tree decl = IDENTIFIER_LABEL_VALUE (name);
2819
2820  if (decl != 0)
2821    {
2822      tree dup;
2823
2824      /* Check to make sure that the label hasn't already been declared
2825	 at this label scope */
2826      for (dup = named_labels; dup; dup = TREE_CHAIN (dup))
2827	if (TREE_VALUE (dup) == decl)
2828	  {
2829	    error ("duplicate label declaration `%s'",
2830		   IDENTIFIER_POINTER (name));
2831	    error_with_decl (TREE_VALUE (dup),
2832			     "this is a previous declaration");
2833	    /* Just use the previous declaration.  */
2834	    return lookup_label (name);
2835	  }
2836
2837      shadowed_labels = tree_cons (NULL_TREE, decl, shadowed_labels);
2838      IDENTIFIER_LABEL_VALUE (name) = decl = 0;
2839    }
2840
2841  return lookup_label (name);
2842}
2843
2844/* Define a label, specifying the location in the source file.
2845   Return the LABEL_DECL node for the label, if the definition is valid.
2846   Otherwise return 0.  */
2847
2848tree
2849define_label (filename, line, name)
2850     const char *filename;
2851     int line;
2852     tree name;
2853{
2854  tree decl = lookup_label (name);
2855
2856  /* If label with this name is known from an outer context, shadow it.  */
2857  if (decl != 0 && DECL_CONTEXT (decl) != current_function_decl)
2858    {
2859      shadowed_labels = tree_cons (NULL_TREE, decl, shadowed_labels);
2860      IDENTIFIER_LABEL_VALUE (name) = 0;
2861      decl = lookup_label (name);
2862    }
2863
2864  if (warn_traditional && !in_system_header && lookup_name (name))
2865    warning_with_file_and_line (filename, line,
2866				"traditional C lacks a separate namespace for labels, identifier `%s' conflicts",
2867				IDENTIFIER_POINTER (name));
2868
2869  if (DECL_INITIAL (decl) != 0)
2870    {
2871      error_with_file_and_line (filename, line, "duplicate label `%s'",
2872				IDENTIFIER_POINTER (name));
2873      return 0;
2874    }
2875  else
2876    {
2877      /* Mark label as having been defined.  */
2878      DECL_INITIAL (decl) = error_mark_node;
2879      /* Say where in the source.  */
2880      DECL_SOURCE_FILE (decl) = filename;
2881      DECL_SOURCE_LINE (decl) = line;
2882      return decl;
2883    }
2884}
2885
2886/* Return the list of declarations of the current level.
2887   Note that this list is in reverse order unless/until
2888   you nreverse it; and when you do nreverse it, you must
2889   store the result back using `storedecls' or you will lose.  */
2890
2891tree
2892getdecls ()
2893{
2894  return current_binding_level->names;
2895}
2896
2897/* Return the list of type-tags (for structs, etc) of the current level.  */
2898
2899tree
2900gettags ()
2901{
2902  return current_binding_level->tags;
2903}
2904
2905/* Store the list of declarations of the current level.
2906   This is done for the parameter declarations of a function being defined,
2907   after they are modified in the light of any missing parameters.  */
2908
2909static void
2910storedecls (decls)
2911     tree decls;
2912{
2913  current_binding_level->names = decls;
2914}
2915
2916/* Similarly, store the list of tags of the current level.  */
2917
2918static void
2919storetags (tags)
2920     tree tags;
2921{
2922  current_binding_level->tags = tags;
2923}
2924
2925/* Given NAME, an IDENTIFIER_NODE,
2926   return the structure (or union or enum) definition for that name.
2927   Searches binding levels from BINDING_LEVEL up to the global level.
2928   If THISLEVEL_ONLY is nonzero, searches only the specified context
2929   (but skips any tag-transparent contexts to find one that is
2930   meaningful for tags).
2931   CODE says which kind of type the caller wants;
2932   it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
2933   If the wrong kind of type is found, an error is reported.  */
2934
2935static tree
2936lookup_tag (code, name, binding_level, thislevel_only)
2937     enum tree_code code;
2938     struct binding_level *binding_level;
2939     tree name;
2940     int thislevel_only;
2941{
2942  struct binding_level *level;
2943  int thislevel = 1;
2944
2945  for (level = binding_level; level; level = level->level_chain)
2946    {
2947      tree tail;
2948      for (tail = level->tags; tail; tail = TREE_CHAIN (tail))
2949	{
2950	  if (TREE_PURPOSE (tail) == name)
2951	    {
2952	      if (TREE_CODE (TREE_VALUE (tail)) != code)
2953		{
2954		  /* Definition isn't the kind we were looking for.  */
2955		  pending_invalid_xref = name;
2956		  pending_invalid_xref_file = input_filename;
2957		  pending_invalid_xref_line = lineno;
2958		  /* If in the same binding level as a declaration as a tag
2959		     of a different type, this must not be allowed to
2960		     shadow that tag, so give the error immediately.
2961		     (For example, "struct foo; union foo;" is invalid.)  */
2962		  if (thislevel)
2963		    pending_xref_error ();
2964		}
2965	      return TREE_VALUE (tail);
2966	    }
2967	}
2968      if (! level->tag_transparent)
2969	{
2970	  if (thislevel_only)
2971	    return NULL_TREE;
2972	  thislevel = 0;
2973	}
2974    }
2975  return NULL_TREE;
2976}
2977
2978/* Print an error message now
2979   for a recent invalid struct, union or enum cross reference.
2980   We don't print them immediately because they are not invalid
2981   when used in the `struct foo;' construct for shadowing.  */
2982
2983void
2984pending_xref_error ()
2985{
2986  if (pending_invalid_xref != 0)
2987    error_with_file_and_line (pending_invalid_xref_file,
2988			      pending_invalid_xref_line,
2989			      "`%s' defined as wrong kind of tag",
2990			      IDENTIFIER_POINTER (pending_invalid_xref));
2991  pending_invalid_xref = 0;
2992}
2993
2994/* Given a type, find the tag that was defined for it and return the tag name.
2995   Otherwise return 0.  */
2996
2997static tree
2998lookup_tag_reverse (type)
2999     tree type;
3000{
3001  struct binding_level *level;
3002
3003  for (level = current_binding_level; level; level = level->level_chain)
3004    {
3005      tree tail;
3006      for (tail = level->tags; tail; tail = TREE_CHAIN (tail))
3007	{
3008	  if (TREE_VALUE (tail) == type)
3009	    return TREE_PURPOSE (tail);
3010	}
3011    }
3012  return NULL_TREE;
3013}
3014
3015/* Look up NAME in the current binding level and its superiors
3016   in the namespace of variables, functions and typedefs.
3017   Return a ..._DECL node of some kind representing its definition,
3018   or return 0 if it is undefined.  */
3019
3020tree
3021lookup_name (name)
3022     tree name;
3023{
3024  tree val;
3025
3026  if (current_binding_level != global_binding_level
3027      && IDENTIFIER_LOCAL_VALUE (name))
3028    val = IDENTIFIER_LOCAL_VALUE (name);
3029  else
3030    val = IDENTIFIER_GLOBAL_VALUE (name);
3031  return val;
3032}
3033
3034/* Similar to `lookup_name' but look only at current binding level.  */
3035
3036tree
3037lookup_name_current_level (name)
3038     tree name;
3039{
3040  tree t;
3041
3042  if (current_binding_level == global_binding_level)
3043    return IDENTIFIER_GLOBAL_VALUE (name);
3044
3045  if (IDENTIFIER_LOCAL_VALUE (name) == 0)
3046    return 0;
3047
3048  for (t = current_binding_level->names; t; t = TREE_CHAIN (t))
3049    if (DECL_NAME (t) == name)
3050      break;
3051
3052  return t;
3053}
3054
3055/* Mark ARG for GC.  */
3056
3057static void
3058mark_binding_level (arg)
3059     void *arg;
3060{
3061  struct binding_level *level = *(struct binding_level **) arg;
3062
3063  for (; level != 0; level = level->level_chain)
3064    {
3065      ggc_mark_tree (level->names);
3066      ggc_mark_tree (level->tags);
3067      ggc_mark_tree (level->shadowed);
3068      ggc_mark_tree (level->blocks);
3069      ggc_mark_tree (level->this_block);
3070      ggc_mark_tree (level->parm_order);
3071    }
3072}
3073
3074/* Create the predefined scalar types of C,
3075   and some nodes representing standard constants (0, 1, (void *) 0).
3076   Initialize the global binding level.
3077   Make definitions for built-in primitive functions.  */
3078
3079void
3080c_init_decl_processing ()
3081{
3082  tree endlink;
3083  tree ptr_ftype_void, ptr_ftype_ptr;
3084
3085  /* Adds some ggc roots, and reserved words for c-parse.in.  */
3086  c_parse_init ();
3087
3088  current_function_decl = NULL;
3089  named_labels = NULL;
3090  current_binding_level = NULL_BINDING_LEVEL;
3091  free_binding_level = NULL_BINDING_LEVEL;
3092
3093  /* Make the binding_level structure for global names.  */
3094  pushlevel (0);
3095  global_binding_level = current_binding_level;
3096
3097  build_common_tree_nodes (flag_signed_char);
3098
3099  c_common_nodes_and_builtins ();
3100
3101  boolean_type_node = integer_type_node;
3102  boolean_true_node = integer_one_node;
3103  boolean_false_node = integer_zero_node;
3104
3105  c_bool_type_node = make_unsigned_type (BOOL_TYPE_SIZE);
3106  TREE_SET_CODE (c_bool_type_node, BOOLEAN_TYPE);
3107  TYPE_MAX_VALUE (c_bool_type_node) = build_int_2 (1, 0);
3108  TREE_TYPE (TYPE_MAX_VALUE (c_bool_type_node)) = c_bool_type_node;
3109  TYPE_PRECISION (c_bool_type_node) = 1;
3110  pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
3111			c_bool_type_node));
3112  c_bool_false_node = build_int_2 (0, 0);
3113  TREE_TYPE (c_bool_false_node) = c_bool_type_node;
3114  c_bool_true_node = build_int_2 (1, 0);
3115  TREE_TYPE (c_bool_true_node) = c_bool_type_node;
3116
3117  endlink = void_list_node;
3118  ptr_ftype_void = build_function_type (ptr_type_node, endlink);
3119  ptr_ftype_ptr
3120    = build_function_type (ptr_type_node,
3121			   tree_cons (NULL_TREE, ptr_type_node, endlink));
3122
3123  /* Types which are common to the fortran compiler and libf2c.  When
3124     changing these, you also need to be concerned with f/com.h.  */
3125
3126  if (TYPE_PRECISION (float_type_node)
3127      == TYPE_PRECISION (long_integer_type_node))
3128    {
3129      g77_integer_type_node = long_integer_type_node;
3130      g77_uinteger_type_node = long_unsigned_type_node;
3131    }
3132  else if (TYPE_PRECISION (float_type_node)
3133	   == TYPE_PRECISION (integer_type_node))
3134    {
3135      g77_integer_type_node = integer_type_node;
3136      g77_uinteger_type_node = unsigned_type_node;
3137    }
3138  else
3139    g77_integer_type_node = g77_uinteger_type_node = NULL_TREE;
3140
3141  if (g77_integer_type_node != NULL_TREE)
3142    {
3143      pushdecl (build_decl (TYPE_DECL, get_identifier ("__g77_integer"),
3144			    g77_integer_type_node));
3145      pushdecl (build_decl (TYPE_DECL, get_identifier ("__g77_uinteger"),
3146			    g77_uinteger_type_node));
3147    }
3148
3149  if (TYPE_PRECISION (float_type_node) * 2
3150      == TYPE_PRECISION (long_integer_type_node))
3151    {
3152      g77_longint_type_node = long_integer_type_node;
3153      g77_ulongint_type_node = long_unsigned_type_node;
3154    }
3155  else if (TYPE_PRECISION (float_type_node) * 2
3156	   == TYPE_PRECISION (long_long_integer_type_node))
3157    {
3158      g77_longint_type_node = long_long_integer_type_node;
3159      g77_ulongint_type_node = long_long_unsigned_type_node;
3160    }
3161  else
3162    g77_longint_type_node = g77_ulongint_type_node = NULL_TREE;
3163
3164  if (g77_longint_type_node != NULL_TREE)
3165    {
3166      pushdecl (build_decl (TYPE_DECL, get_identifier ("__g77_longint"),
3167			    g77_longint_type_node));
3168      pushdecl (build_decl (TYPE_DECL, get_identifier ("__g77_ulongint"),
3169			    g77_ulongint_type_node));
3170    }
3171
3172  pedantic_lvalues = pedantic;
3173
3174  make_fname_decl = c_make_fname_decl;
3175  start_fname_decls ();
3176
3177  incomplete_decl_finalize_hook = finish_incomplete_decl;
3178
3179  /* Record our roots.  */
3180
3181  ggc_add_tree_root (c_global_trees, CTI_MAX);
3182  ggc_add_root (&c_stmt_tree, 1, sizeof c_stmt_tree, mark_stmt_tree);
3183  ggc_add_tree_root (&c_scope_stmt_stack, 1);
3184  ggc_add_tree_root (&named_labels, 1);
3185  ggc_add_tree_root (&shadowed_labels, 1);
3186  ggc_add_root (&current_binding_level, 1, sizeof current_binding_level,
3187		mark_binding_level);
3188  ggc_add_root (&label_level_chain, 1, sizeof label_level_chain,
3189		mark_binding_level);
3190  ggc_add_tree_root (&static_ctors, 1);
3191  ggc_add_tree_root (&static_dtors, 1);
3192}
3193
3194/* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
3195   decl, NAME is the initialization string and TYPE_DEP indicates whether
3196   NAME depended on the type of the function.  As we don't yet implement
3197   delayed emission of static data, we mark the decl as emitted
3198   so it is not placed in the output.  Anything using it must therefore pull
3199   out the STRING_CST initializer directly.  This does mean that these names
3200   are string merging candidates, which is wrong for C99's __func__.  FIXME.  */
3201
3202static tree
3203c_make_fname_decl (id, type_dep)
3204     tree id;
3205     int type_dep;
3206{
3207  const char *name = fname_as_string (type_dep);
3208  tree decl, type, init;
3209  size_t length = strlen (name);
3210
3211  type =  build_array_type
3212          (build_qualified_type (char_type_node, TYPE_QUAL_CONST),
3213	   build_index_type (size_int (length)));
3214
3215  decl = build_decl (VAR_DECL, id, type);
3216  /* We don't push the decl, so have to set its context here.  */
3217  DECL_CONTEXT (decl) = current_function_decl;
3218
3219  TREE_STATIC (decl) = 1;
3220  TREE_READONLY (decl) = 1;
3221  DECL_ARTIFICIAL (decl) = 1;
3222
3223  init = build_string (length + 1, name);
3224  TREE_TYPE (init) = type;
3225  DECL_INITIAL (decl) = init;
3226
3227  TREE_USED (decl) = 1;
3228
3229  finish_decl (decl, init, NULL_TREE);
3230
3231  return decl;
3232}
3233
3234/* Return a definition for a builtin function named NAME and whose data type
3235   is TYPE.  TYPE should be a function type with argument types.
3236   FUNCTION_CODE tells later passes how to compile calls to this function.
3237   See tree.h for its possible values.
3238
3239   If LIBRARY_NAME is nonzero, use that for DECL_ASSEMBLER_NAME,
3240   the name to be called if we can't opencode the function.  */
3241
3242tree
3243builtin_function (name, type, function_code, class, library_name)
3244     const char *name;
3245     tree type;
3246     int function_code;
3247     enum built_in_class class;
3248     const char *library_name;
3249{
3250  tree decl = build_decl (FUNCTION_DECL, get_identifier (name), type);
3251  DECL_EXTERNAL (decl) = 1;
3252  TREE_PUBLIC (decl) = 1;
3253  /* If -traditional, permit redefining a builtin function any way you like.
3254     (Though really, if the program redefines these functions,
3255     it probably won't work right unless compiled with -fno-builtin.)  */
3256  if (flag_traditional && name[0] != '_')
3257    DECL_BUILT_IN_NONANSI (decl) = 1;
3258  if (library_name)
3259    SET_DECL_ASSEMBLER_NAME (decl, get_identifier (library_name));
3260  make_decl_rtl (decl, NULL);
3261  pushdecl (decl);
3262  DECL_BUILT_IN_CLASS (decl) = class;
3263  DECL_FUNCTION_CODE (decl) = function_code;
3264
3265  /* The return builtins leave the current function.  */
3266  if (function_code == BUILT_IN_RETURN || function_code == BUILT_IN_EH_RETURN)
3267    TREE_THIS_VOLATILE (decl) = 1;
3268
3269  /* Warn if a function in the namespace for users
3270     is used without an occasion to consider it declared.  */
3271  if (name[0] != '_' || name[1] != '_')
3272    C_DECL_ANTICIPATED (decl) = 1;
3273
3274  /* Possibly apply some default attributes to this built-in function.  */
3275  decl_attributes (&decl, NULL_TREE, 0);
3276
3277  return decl;
3278}
3279
3280/* Apply default attributes to a function, if a system function with default
3281   attributes.  */
3282
3283void
3284insert_default_attributes (decl)
3285     tree decl;
3286{
3287  if (!TREE_PUBLIC (decl))
3288    return;
3289  c_common_insert_default_attributes (decl);
3290}
3291
3292/* Called when a declaration is seen that contains no names to declare.
3293   If its type is a reference to a structure, union or enum inherited
3294   from a containing scope, shadow that tag name for the current scope
3295   with a forward reference.
3296   If its type defines a new named structure or union
3297   or defines an enum, it is valid but we need not do anything here.
3298   Otherwise, it is an error.  */
3299
3300void
3301shadow_tag (declspecs)
3302     tree declspecs;
3303{
3304  shadow_tag_warned (declspecs, 0);
3305}
3306
3307void
3308shadow_tag_warned (declspecs, warned)
3309     tree declspecs;
3310     int warned;
3311     /* 1 => we have done a pedwarn.  2 => we have done a warning, but
3312	no pedwarn.  */
3313{
3314  int found_tag = 0;
3315  tree link;
3316  tree specs, attrs;
3317
3318  pending_invalid_xref = 0;
3319
3320  /* Remove the attributes from declspecs, since they will confuse the
3321     following code.  */
3322  split_specs_attrs (declspecs, &specs, &attrs);
3323
3324  for (link = specs; link; link = TREE_CHAIN (link))
3325    {
3326      tree value = TREE_VALUE (link);
3327      enum tree_code code = TREE_CODE (value);
3328
3329      if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
3330	/* Used to test also that TYPE_SIZE (value) != 0.
3331	   That caused warning for `struct foo;' at top level in the file.  */
3332	{
3333	  tree name = lookup_tag_reverse (value);
3334	  tree t;
3335
3336	  found_tag++;
3337
3338	  if (name == 0)
3339	    {
3340	      if (warned != 1 && code != ENUMERAL_TYPE)
3341		/* Empty unnamed enum OK */
3342		{
3343		  pedwarn ("unnamed struct/union that defines no instances");
3344		  warned = 1;
3345		}
3346	    }
3347	  else
3348	    {
3349	      t = lookup_tag (code, name, current_binding_level, 1);
3350
3351	      if (t == 0)
3352		{
3353		  t = make_node (code);
3354		  pushtag (name, t);
3355		}
3356	    }
3357	}
3358      else
3359	{
3360	  if (!warned && ! in_system_header)
3361	    {
3362	      warning ("useless keyword or type name in empty declaration");
3363	      warned = 2;
3364	    }
3365	}
3366    }
3367
3368  if (found_tag > 1)
3369    error ("two types specified in one empty declaration");
3370
3371  if (warned != 1)
3372    {
3373      if (found_tag == 0)
3374	pedwarn ("empty declaration");
3375    }
3376}
3377
3378/* Construct an array declarator.  EXPR is the expression inside [], or
3379   NULL_TREE.  QUALS are the type qualifiers inside the [] (to be applied
3380   to the pointer to which a parameter array is converted).  STATIC_P is
3381   non-zero if "static" is inside the [], zero otherwise.  VLA_UNSPEC_P
3382   is non-zero is the array is [*], a VLA of unspecified length which is
3383   nevertheless a complete type (not currently implemented by GCC),
3384   zero otherwise.  The declarator is constructed as an ARRAY_REF
3385   (to be decoded by grokdeclarator), whose operand 0 is what's on the
3386   left of the [] (filled by in set_array_declarator_type) and operand 1
3387   is the expression inside; whose TREE_TYPE is the type qualifiers and
3388   which has TREE_STATIC set if "static" is used.  */
3389
3390tree
3391build_array_declarator (expr, quals, static_p, vla_unspec_p)
3392     tree expr;
3393     tree quals;
3394     int static_p;
3395     int vla_unspec_p;
3396{
3397  tree decl;
3398  decl = build_nt (ARRAY_REF, NULL_TREE, expr);
3399  TREE_TYPE (decl) = quals;
3400  TREE_STATIC (decl) = (static_p ? 1 : 0);
3401  if (pedantic && !flag_isoc99)
3402    {
3403      if (static_p || quals != NULL_TREE)
3404	pedwarn ("ISO C89 does not support `static' or type qualifiers in parameter array declarators");
3405      if (vla_unspec_p)
3406	pedwarn ("ISO C89 does not support `[*]' array declarators");
3407    }
3408  if (vla_unspec_p)
3409    warning ("GCC does not yet properly implement `[*]' array declarators");
3410  return decl;
3411}
3412
3413/* Set the type of an array declarator.  DECL is the declarator, as
3414   constructed by build_array_declarator; TYPE is what appears on the left
3415   of the [] and goes in operand 0.  ABSTRACT_P is non-zero if it is an
3416   abstract declarator, zero otherwise; this is used to reject static and
3417   type qualifiers in abstract declarators, where they are not in the
3418   C99 grammar.  */
3419
3420tree
3421set_array_declarator_type (decl, type, abstract_p)
3422     tree decl;
3423     tree type;
3424     int abstract_p;
3425{
3426  TREE_OPERAND (decl, 0) = type;
3427  if (abstract_p && (TREE_TYPE (decl) != NULL_TREE || TREE_STATIC (decl)))
3428    error ("static or type qualifiers in abstract declarator");
3429  return decl;
3430}
3431
3432/* Decode a "typename", such as "int **", returning a ..._TYPE node.  */
3433
3434tree
3435groktypename (typename)
3436     tree typename;
3437{
3438  tree specs, attrs;
3439
3440  if (TREE_CODE (typename) != TREE_LIST)
3441    return typename;
3442
3443  split_specs_attrs (TREE_PURPOSE (typename), &specs, &attrs);
3444
3445  typename = grokdeclarator (TREE_VALUE (typename), specs, TYPENAME, 0);
3446
3447  /* Apply attributes.  */
3448  decl_attributes (&typename, attrs, 0);
3449
3450  return typename;
3451}
3452
3453/* Return a PARM_DECL node for a given pair of specs and declarator.  */
3454
3455tree
3456groktypename_in_parm_context (typename)
3457     tree typename;
3458{
3459  if (TREE_CODE (typename) != TREE_LIST)
3460    return typename;
3461  return grokdeclarator (TREE_VALUE (typename),
3462			 TREE_PURPOSE (typename),
3463			 PARM, 0);
3464}
3465
3466/* Decode a declarator in an ordinary declaration or data definition.
3467   This is called as soon as the type information and variable name
3468   have been parsed, before parsing the initializer if any.
3469   Here we create the ..._DECL node, fill in its type,
3470   and put it on the list of decls for the current context.
3471   The ..._DECL node is returned as the value.
3472
3473   Exception: for arrays where the length is not specified,
3474   the type is left null, to be filled in by `finish_decl'.
3475
3476   Function definitions do not come here; they go to start_function
3477   instead.  However, external and forward declarations of functions
3478   do go through here.  Structure field declarations are done by
3479   grokfield and not through here.  */
3480
3481tree
3482start_decl (declarator, declspecs, initialized, attributes)
3483     tree declarator, declspecs;
3484     int initialized;
3485     tree attributes;
3486{
3487  tree decl;
3488  tree tem;
3489
3490  /* An object declared as __attribute__((deprecated)) suppresses
3491     warnings of uses of other deprecated items.  */
3492  if (lookup_attribute ("deprecated", attributes))
3493    deprecated_state = DEPRECATED_SUPPRESS;
3494
3495  decl = grokdeclarator (declarator, declspecs,
3496			 NORMAL, initialized);
3497
3498  deprecated_state = DEPRECATED_NORMAL;
3499
3500  if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
3501      && MAIN_NAME_P (DECL_NAME (decl)))
3502    warning_with_decl (decl, "`%s' is usually a function");
3503
3504  if (initialized)
3505    /* Is it valid for this decl to have an initializer at all?
3506       If not, set INITIALIZED to zero, which will indirectly
3507       tell `finish_decl' to ignore the initializer once it is parsed.  */
3508    switch (TREE_CODE (decl))
3509      {
3510      case TYPE_DECL:
3511	/* typedef foo = bar  means give foo the same type as bar.
3512	   We haven't parsed bar yet, so `finish_decl' will fix that up.
3513	   Any other case of an initialization in a TYPE_DECL is an error.  */
3514	if (pedantic || list_length (declspecs) > 1)
3515	  {
3516	    error ("typedef `%s' is initialized",
3517		   IDENTIFIER_POINTER (DECL_NAME (decl)));
3518	    initialized = 0;
3519	  }
3520	break;
3521
3522      case FUNCTION_DECL:
3523	error ("function `%s' is initialized like a variable",
3524	       IDENTIFIER_POINTER (DECL_NAME (decl)));
3525	initialized = 0;
3526	break;
3527
3528      case PARM_DECL:
3529	/* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE.  */
3530	error ("parameter `%s' is initialized",
3531	       IDENTIFIER_POINTER (DECL_NAME (decl)));
3532	initialized = 0;
3533	break;
3534
3535      default:
3536	/* Don't allow initializations for incomplete types
3537	   except for arrays which might be completed by the initialization.  */
3538
3539	/* This can happen if the array size is an undefined macro.  We already
3540	   gave a warning, so we don't need another one.  */
3541	if (TREE_TYPE (decl) == error_mark_node)
3542	  initialized = 0;
3543	else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
3544	  {
3545	    /* A complete type is ok if size is fixed.  */
3546
3547	    if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
3548		|| C_DECL_VARIABLE_SIZE (decl))
3549	      {
3550		error ("variable-sized object may not be initialized");
3551		initialized = 0;
3552	      }
3553	  }
3554	else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
3555	  {
3556	    error ("variable `%s' has initializer but incomplete type",
3557		   IDENTIFIER_POINTER (DECL_NAME (decl)));
3558	    initialized = 0;
3559	  }
3560	else if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
3561	  {
3562	    error ("elements of array `%s' have incomplete type",
3563		   IDENTIFIER_POINTER (DECL_NAME (decl)));
3564	    initialized = 0;
3565	  }
3566      }
3567
3568  if (initialized)
3569    {
3570#if 0
3571      /* Seems redundant with grokdeclarator.  */
3572      if (current_binding_level != global_binding_level
3573	  && DECL_EXTERNAL (decl)
3574	  && TREE_CODE (decl) != FUNCTION_DECL)
3575	warning ("declaration of `%s' has `extern' and is initialized",
3576		 IDENTIFIER_POINTER (DECL_NAME (decl)));
3577#endif
3578      DECL_EXTERNAL (decl) = 0;
3579      if (current_binding_level == global_binding_level)
3580	TREE_STATIC (decl) = 1;
3581
3582      /* Tell `pushdecl' this is an initialized decl
3583	 even though we don't yet have the initializer expression.
3584	 Also tell `finish_decl' it may store the real initializer.  */
3585      DECL_INITIAL (decl) = error_mark_node;
3586    }
3587
3588  /* If this is a function declaration, write a record describing it to the
3589     prototypes file (if requested).  */
3590
3591  if (TREE_CODE (decl) == FUNCTION_DECL)
3592    gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);
3593
3594  /* ANSI specifies that a tentative definition which is not merged with
3595     a non-tentative definition behaves exactly like a definition with an
3596     initializer equal to zero.  (Section 3.7.2)
3597     -fno-common gives strict ANSI behavior.  Usually you don't want it.
3598     This matters only for variables with external linkage.  */
3599  if (! flag_no_common || ! TREE_PUBLIC (decl))
3600    DECL_COMMON (decl) = 1;
3601
3602  /* Set attributes here so if duplicate decl, will have proper attributes.  */
3603  decl_attributes (&decl, attributes, 0);
3604
3605  /* If #pragma weak was used, mark the decl weak now.  */
3606  if (current_binding_level == global_binding_level)
3607    maybe_apply_pragma_weak (decl);
3608
3609  if (TREE_CODE (decl) == FUNCTION_DECL
3610      && DECL_DECLARED_INLINE_P (decl)
3611      && DECL_UNINLINABLE (decl)
3612      && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
3613    warning_with_decl (decl,
3614		       "inline function `%s' given attribute noinline");
3615
3616  /* Add this decl to the current binding level.
3617     TEM may equal DECL or it may be a previous decl of the same name.  */
3618  tem = pushdecl (decl);
3619
3620  /* For a local variable, define the RTL now.  */
3621  if (current_binding_level != global_binding_level
3622      /* But not if this is a duplicate decl
3623	 and we preserved the rtl from the previous one
3624	 (which may or may not happen).  */
3625      && !DECL_RTL_SET_P (tem)
3626      && !DECL_CONTEXT (tem))
3627    {
3628      if (TREE_TYPE (tem) != error_mark_node
3629	  && COMPLETE_TYPE_P (TREE_TYPE (tem)))
3630	expand_decl (tem);
3631      else if (TREE_CODE (TREE_TYPE (tem)) == ARRAY_TYPE
3632	       && DECL_INITIAL (tem) != 0)
3633	expand_decl (tem);
3634    }
3635
3636  return tem;
3637}
3638
3639/* Finish processing of a declaration;
3640   install its initial value.
3641   If the length of an array type is not known before,
3642   it must be determined now, from the initial value, or it is an error.  */
3643
3644void
3645finish_decl (decl, init, asmspec_tree)
3646     tree decl, init;
3647     tree asmspec_tree;
3648{
3649  tree type = TREE_TYPE (decl);
3650  int was_incomplete = (DECL_SIZE (decl) == 0);
3651  const char *asmspec = 0;
3652
3653  /* If a name was specified, get the string.  */
3654  if (current_binding_level == global_binding_level)
3655    asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
3656  if (asmspec_tree)
3657    asmspec = TREE_STRING_POINTER (asmspec_tree);
3658
3659  /* If `start_decl' didn't like having an initialization, ignore it now.  */
3660  if (init != 0 && DECL_INITIAL (decl) == 0)
3661    init = 0;
3662
3663  /* Don't crash if parm is initialized.  */
3664  if (TREE_CODE (decl) == PARM_DECL)
3665    init = 0;
3666
3667  if (init)
3668    {
3669      if (TREE_CODE (decl) != TYPE_DECL)
3670	store_init_value (decl, init);
3671      else
3672	{
3673	  /* typedef foo = bar; store the type of bar as the type of foo.  */
3674	  TREE_TYPE (decl) = TREE_TYPE (init);
3675	  DECL_INITIAL (decl) = init = 0;
3676	}
3677    }
3678
3679  /* Deduce size of array from initialization, if not already known */
3680  if (TREE_CODE (type) == ARRAY_TYPE
3681      && TYPE_DOMAIN (type) == 0
3682      && TREE_CODE (decl) != TYPE_DECL)
3683    {
3684      int do_default
3685	= (TREE_STATIC (decl)
3686	   /* Even if pedantic, an external linkage array
3687	      may have incomplete type at first.  */
3688	   ? pedantic && !TREE_PUBLIC (decl)
3689	   : !DECL_EXTERNAL (decl));
3690      int failure
3691	= complete_array_type (type, DECL_INITIAL (decl), do_default);
3692
3693      /* Get the completed type made by complete_array_type.  */
3694      type = TREE_TYPE (decl);
3695
3696      if (failure == 1)
3697	error_with_decl (decl, "initializer fails to determine size of `%s'");
3698
3699      else if (failure == 2)
3700	{
3701	  if (do_default)
3702	    error_with_decl (decl, "array size missing in `%s'");
3703	  /* If a `static' var's size isn't known,
3704	     make it extern as well as static, so it does not get
3705	     allocated.
3706	     If it is not `static', then do not mark extern;
3707	     finish_incomplete_decl will give it a default size
3708	     and it will get allocated.  */
3709	  else if (!pedantic && TREE_STATIC (decl) && ! TREE_PUBLIC (decl))
3710	    DECL_EXTERNAL (decl) = 1;
3711	}
3712
3713      /* TYPE_MAX_VALUE is always one less than the number of elements
3714	 in the array, because we start counting at zero.  Therefore,
3715	 warn only if the value is less than zero.  */
3716      else if (pedantic && TYPE_DOMAIN (type) != 0
3717	      && tree_int_cst_sgn (TYPE_MAX_VALUE (TYPE_DOMAIN (type))) < 0)
3718	error_with_decl (decl, "zero or negative size array `%s'");
3719
3720      layout_decl (decl, 0);
3721    }
3722
3723  if (TREE_CODE (decl) == VAR_DECL)
3724    {
3725      if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
3726	  && COMPLETE_TYPE_P (TREE_TYPE (decl)))
3727	layout_decl (decl, 0);
3728
3729      if (DECL_SIZE (decl) == 0
3730	  /* Don't give an error if we already gave one earlier.  */
3731	  && TREE_TYPE (decl) != error_mark_node
3732	  && (TREE_STATIC (decl)
3733	      ?
3734		/* A static variable with an incomplete type
3735		   is an error if it is initialized.
3736		   Also if it is not file scope.
3737		   Otherwise, let it through, but if it is not `extern'
3738		   then it may cause an error message later.  */
3739		(DECL_INITIAL (decl) != 0
3740		 || DECL_CONTEXT (decl) != 0)
3741	      :
3742		/* An automatic variable with an incomplete type
3743		   is an error.  */
3744		!DECL_EXTERNAL (decl)))
3745	{
3746	  error_with_decl (decl, "storage size of `%s' isn't known");
3747	  TREE_TYPE (decl) = error_mark_node;
3748	}
3749
3750      if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
3751	  && DECL_SIZE (decl) != 0)
3752	{
3753	  if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
3754	    constant_expression_warning (DECL_SIZE (decl));
3755	  else
3756	    error_with_decl (decl, "storage size of `%s' isn't constant");
3757	}
3758
3759      if (TREE_USED (type))
3760	TREE_USED (decl) = 1;
3761    }
3762
3763  /* If this is a function and an assembler name is specified, it isn't
3764     builtin any more.  Also reset DECL_RTL so we can give it its new
3765     name.  */
3766  if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
3767    {
3768      DECL_BUILT_IN_CLASS (decl) = NOT_BUILT_IN;
3769      SET_DECL_RTL (decl, NULL_RTX);
3770      SET_DECL_ASSEMBLER_NAME (decl, get_identifier (asmspec));
3771    }
3772
3773  /* Output the assembler code and/or RTL code for variables and functions,
3774     unless the type is an undefined structure or union.
3775     If not, it will get done when the type is completed.  */
3776
3777  if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
3778    {
3779      /* This is a no-op in c-lang.c or something real in objc-actions.c.  */
3780      maybe_objc_check_decl (decl);
3781
3782      if (!DECL_CONTEXT (decl))
3783	{
3784	  if (DECL_INITIAL (decl) == NULL_TREE
3785	      || DECL_INITIAL (decl) == error_mark_node)
3786	    /* Don't output anything
3787	       when a tentative file-scope definition is seen.
3788	       But at end of compilation, do output code for them.  */
3789	    DECL_DEFER_OUTPUT (decl) = 1;
3790	  rest_of_decl_compilation (decl, asmspec,
3791				    (DECL_CONTEXT (decl) == 0
3792				     || TREE_ASM_WRITTEN (decl)), 0);
3793	}
3794      else
3795	{
3796	  /* This is a local variable.  If there is an ASMSPEC, the
3797	     user has requested that we handle it specially.  */
3798	  if (asmspec)
3799	    {
3800	      /* In conjunction with an ASMSPEC, the `register'
3801		 keyword indicates that we should place the variable
3802		 in a particular register.  */
3803	      if (DECL_REGISTER (decl))
3804		DECL_C_HARD_REGISTER (decl) = 1;
3805
3806	      /* If this is not a static variable, issue a warning.
3807		 It doesn't make any sense to give an ASMSPEC for an
3808		 ordinary, non-register local variable.  Historically,
3809		 GCC has accepted -- but ignored -- the ASMSPEC in
3810		 this case.  */
3811	      if (TREE_CODE (decl) == VAR_DECL
3812		  && !DECL_REGISTER (decl)
3813		  && !TREE_STATIC (decl))
3814		warning_with_decl (decl,
3815				   "ignoring asm-specifier for non-static local variable `%s'");
3816	      else
3817		SET_DECL_ASSEMBLER_NAME (decl, get_identifier (asmspec));
3818	    }
3819
3820	  if (TREE_CODE (decl) != FUNCTION_DECL)
3821	    add_decl_stmt (decl);
3822	}
3823
3824      if (DECL_CONTEXT (decl) != 0)
3825	{
3826	  /* Recompute the RTL of a local array now
3827	     if it used to be an incomplete type.  */
3828	  if (was_incomplete
3829	      && ! TREE_STATIC (decl) && ! DECL_EXTERNAL (decl))
3830	    {
3831	      /* If we used it already as memory, it must stay in memory.  */
3832	      TREE_ADDRESSABLE (decl) = TREE_USED (decl);
3833	      /* If it's still incomplete now, no init will save it.  */
3834	      if (DECL_SIZE (decl) == 0)
3835		DECL_INITIAL (decl) = 0;
3836	    }
3837	}
3838    }
3839
3840  if (TREE_CODE (decl) == TYPE_DECL)
3841    {
3842      /* This is a no-op in c-lang.c or something real in objc-actions.c.  */
3843      maybe_objc_check_decl (decl);
3844      rest_of_decl_compilation (decl, NULL, DECL_CONTEXT (decl) == 0, 0);
3845    }
3846
3847  /* At the end of a declaration, throw away any variable type sizes
3848     of types defined inside that declaration.  There is no use
3849     computing them in the following function definition.  */
3850  if (current_binding_level == global_binding_level)
3851    get_pending_sizes ();
3852}
3853
3854/* If DECL has a cleanup, build and return that cleanup here.
3855   This is a callback called by expand_expr.  */
3856
3857tree
3858maybe_build_cleanup (decl)
3859     tree decl ATTRIBUTE_UNUSED;
3860{
3861  /* There are no cleanups in C.  */
3862  return NULL_TREE;
3863}
3864
3865/* Given a parsed parameter declaration,
3866   decode it into a PARM_DECL and push that on the current binding level.
3867   Also, for the sake of forward parm decls,
3868   record the given order of parms in `parm_order'.  */
3869
3870void
3871push_parm_decl (parm)
3872     tree parm;
3873{
3874  tree decl;
3875  int old_immediate_size_expand = immediate_size_expand;
3876  /* Don't try computing parm sizes now -- wait till fn is called.  */
3877  immediate_size_expand = 0;
3878
3879  decl = grokdeclarator (TREE_VALUE (TREE_PURPOSE (parm)),
3880			 TREE_PURPOSE (TREE_PURPOSE (parm)), PARM, 0);
3881  decl_attributes (&decl, TREE_VALUE (parm), 0);
3882
3883#if 0
3884  if (DECL_NAME (decl))
3885    {
3886      tree olddecl;
3887      olddecl = lookup_name (DECL_NAME (decl));
3888      if (pedantic && olddecl != 0 && TREE_CODE (olddecl) == TYPE_DECL)
3889	pedwarn_with_decl (decl,
3890			   "ISO C forbids parameter `%s' shadowing typedef");
3891    }
3892#endif
3893
3894  decl = pushdecl (decl);
3895
3896  immediate_size_expand = old_immediate_size_expand;
3897
3898  current_binding_level->parm_order
3899    = tree_cons (NULL_TREE, decl, current_binding_level->parm_order);
3900
3901  /* Add this decl to the current binding level.  */
3902  finish_decl (decl, NULL_TREE, NULL_TREE);
3903}
3904
3905/* Clear the given order of parms in `parm_order'.
3906   Used at start of parm list,
3907   and also at semicolon terminating forward decls.  */
3908
3909void
3910clear_parm_order ()
3911{
3912  current_binding_level->parm_order = NULL_TREE;
3913}
3914
3915/* Build a COMPOUND_LITERAL_EXPR.  TYPE is the type given in the compound
3916   literal, which may be an incomplete array type completed by the
3917   initializer; INIT is a CONSTRUCTOR that initializes the compound
3918   literal.  */
3919
3920tree
3921build_compound_literal (type, init)
3922     tree type;
3923     tree init;
3924{
3925  /* We do not use start_decl here because we have a type, not a declarator;
3926     and do not use finish_decl because the decl should be stored inside
3927     the COMPOUND_LITERAL_EXPR rather than added elsewhere as a DECL_STMT.  */
3928  tree decl = build_decl (VAR_DECL, NULL_TREE, type);
3929  tree complit;
3930  tree stmt;
3931  DECL_EXTERNAL (decl) = 0;
3932  TREE_PUBLIC (decl) = 0;
3933  TREE_STATIC (decl) = (current_binding_level == global_binding_level);
3934  DECL_CONTEXT (decl) = current_function_decl;
3935  TREE_USED (decl) = 1;
3936  TREE_TYPE (decl) = type;
3937  store_init_value (decl, init);
3938
3939  if (TREE_CODE (type) == ARRAY_TYPE && !COMPLETE_TYPE_P (type))
3940    {
3941      int failure = complete_array_type (type, DECL_INITIAL (decl), 1);
3942      if (failure)
3943	abort ();
3944    }
3945
3946  type = TREE_TYPE (decl);
3947  if (type == error_mark_node || !COMPLETE_TYPE_P (type))
3948    return error_mark_node;
3949
3950  stmt = build_stmt (DECL_STMT, decl);
3951  complit = build1 (COMPOUND_LITERAL_EXPR, TREE_TYPE (decl), stmt);
3952  TREE_SIDE_EFFECTS (complit) = 1;
3953
3954  layout_decl (decl, 0);
3955
3956  if (TREE_STATIC (decl))
3957    {
3958      /* This decl needs a name for the assembler output.  We also need
3959	 a unique suffix to be added to the name, for which DECL_CONTEXT
3960	 must be set.  */
3961      DECL_NAME (decl) = get_identifier ("__compound_literal");
3962      DECL_CONTEXT (decl) = complit;
3963      rest_of_decl_compilation (decl, NULL, 1, 0);
3964      DECL_CONTEXT (decl) = NULL_TREE;
3965    }
3966
3967  return complit;
3968}
3969
3970/* Make TYPE a complete type based on INITIAL_VALUE.
3971   Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
3972   2 if there was no information (in which case assume 1 if DO_DEFAULT).  */
3973
3974int
3975complete_array_type (type, initial_value, do_default)
3976     tree type;
3977     tree initial_value;
3978     int do_default;
3979{
3980  tree maxindex = NULL_TREE;
3981  int value = 0;
3982
3983  if (initial_value)
3984    {
3985      /* Note MAXINDEX  is really the maximum index,
3986	 one less than the size.  */
3987      if (TREE_CODE (initial_value) == STRING_CST)
3988	{
3989	  int eltsize
3990	    = int_size_in_bytes (TREE_TYPE (TREE_TYPE (initial_value)));
3991	  maxindex = build_int_2 ((TREE_STRING_LENGTH (initial_value)
3992				   / eltsize) - 1, 0);
3993	}
3994      else if (TREE_CODE (initial_value) == CONSTRUCTOR)
3995	{
3996	  tree elts = CONSTRUCTOR_ELTS (initial_value);
3997	  maxindex = build_int_2 (-1, -1);
3998	  for (; elts; elts = TREE_CHAIN (elts))
3999	    {
4000	      if (TREE_PURPOSE (elts))
4001		maxindex = TREE_PURPOSE (elts);
4002	      else
4003		maxindex = fold (build (PLUS_EXPR, integer_type_node,
4004					maxindex, integer_one_node));
4005	    }
4006	  maxindex = copy_node (maxindex);
4007	}
4008      else
4009	{
4010	  /* Make an error message unless that happened already.  */
4011	  if (initial_value != error_mark_node)
4012	    value = 1;
4013
4014	  /* Prevent further error messages.  */
4015	  maxindex = build_int_2 (0, 0);
4016	}
4017    }
4018
4019  if (!maxindex)
4020    {
4021      if (do_default)
4022	maxindex = build_int_2 (0, 0);
4023      value = 2;
4024    }
4025
4026  if (maxindex)
4027    {
4028      TYPE_DOMAIN (type) = build_index_type (maxindex);
4029      if (!TREE_TYPE (maxindex))
4030	TREE_TYPE (maxindex) = TYPE_DOMAIN (type);
4031    }
4032
4033  /* Lay out the type now that we can get the real answer.  */
4034
4035  layout_type (type);
4036
4037  return value;
4038}
4039
4040/* Given declspecs and a declarator,
4041   determine the name and type of the object declared
4042   and construct a ..._DECL node for it.
4043   (In one case we can return a ..._TYPE node instead.
4044    For invalid input we sometimes return 0.)
4045
4046   DECLSPECS is a chain of tree_list nodes whose value fields
4047    are the storage classes and type specifiers.
4048
4049   DECL_CONTEXT says which syntactic context this declaration is in:
4050     NORMAL for most contexts.  Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
4051     FUNCDEF for a function definition.  Like NORMAL but a few different
4052      error messages in each case.  Return value may be zero meaning
4053      this definition is too screwy to try to parse.
4054     PARM for a parameter declaration (either within a function prototype
4055      or before a function body).  Make a PARM_DECL, or return void_type_node.
4056     TYPENAME if for a typename (in a cast or sizeof).
4057      Don't make a DECL node; just return the ..._TYPE node.
4058     FIELD for a struct or union field; make a FIELD_DECL.
4059     BITFIELD for a field with specified width.
4060   INITIALIZED is 1 if the decl has an initializer.
4061
4062   In the TYPENAME case, DECLARATOR is really an absolute declarator.
4063   It may also be so in the PARM case, for a prototype where the
4064   argument type is specified but not the name.
4065
4066   This function is where the complicated C meanings of `static'
4067   and `extern' are interpreted.  */
4068
4069static tree
4070grokdeclarator (declarator, declspecs, decl_context, initialized)
4071     tree declspecs;
4072     tree declarator;
4073     enum decl_context decl_context;
4074     int initialized;
4075{
4076  int specbits = 0;
4077  tree spec;
4078  tree type = NULL_TREE;
4079  int longlong = 0;
4080  int constp;
4081  int restrictp;
4082  int volatilep;
4083  int type_quals = TYPE_UNQUALIFIED;
4084  int inlinep;
4085  int explicit_int = 0;
4086  int explicit_char = 0;
4087  int defaulted_int = 0;
4088  tree typedef_decl = 0;
4089  const char *name;
4090  tree typedef_type = 0;
4091  int funcdef_flag = 0;
4092  enum tree_code innermost_code = ERROR_MARK;
4093  int bitfield = 0;
4094  int size_varies = 0;
4095  tree decl_attr = NULL_TREE;
4096  tree array_ptr_quals = NULL_TREE;
4097  int array_parm_static = 0;
4098  tree returned_attrs = NULL_TREE;
4099
4100  if (decl_context == BITFIELD)
4101    bitfield = 1, decl_context = FIELD;
4102
4103  if (decl_context == FUNCDEF)
4104    funcdef_flag = 1, decl_context = NORMAL;
4105
4106  /* Look inside a declarator for the name being declared
4107     and get it as a string, for an error message.  */
4108  {
4109    tree decl = declarator;
4110    name = 0;
4111
4112    while (decl)
4113      switch (TREE_CODE (decl))
4114	{
4115	case ARRAY_REF:
4116	case INDIRECT_REF:
4117	case CALL_EXPR:
4118	  innermost_code = TREE_CODE (decl);
4119	  decl = TREE_OPERAND (decl, 0);
4120	  break;
4121
4122	case TREE_LIST:
4123	  decl = TREE_VALUE (decl);
4124	  break;
4125
4126	case IDENTIFIER_NODE:
4127	  name = IDENTIFIER_POINTER (decl);
4128	  decl = 0;
4129	  break;
4130
4131	default:
4132	  abort ();
4133	}
4134    if (name == 0)
4135      name = "type name";
4136  }
4137
4138  /* A function definition's declarator must have the form of
4139     a function declarator.  */
4140
4141  if (funcdef_flag && innermost_code != CALL_EXPR)
4142    return 0;
4143
4144  /* Anything declared one level down from the top level
4145     must be one of the parameters of a function
4146     (because the body is at least two levels down).  */
4147
4148  /* If this looks like a function definition, make it one,
4149     even if it occurs where parms are expected.
4150     Then store_parm_decls will reject it and not use it as a parm.  */
4151  if (decl_context == NORMAL && !funcdef_flag
4152      && current_binding_level->parm_flag)
4153    decl_context = PARM;
4154
4155  /* Look through the decl specs and record which ones appear.
4156     Some typespecs are defined as built-in typenames.
4157     Others, the ones that are modifiers of other types,
4158     are represented by bits in SPECBITS: set the bits for
4159     the modifiers that appear.  Storage class keywords are also in SPECBITS.
4160
4161     If there is a typedef name or a type, store the type in TYPE.
4162     This includes builtin typedefs such as `int'.
4163
4164     Set EXPLICIT_INT or EXPLICIT_CHAR if the type is `int' or `char'
4165     and did not come from a user typedef.
4166
4167     Set LONGLONG if `long' is mentioned twice.  */
4168
4169  for (spec = declspecs; spec; spec = TREE_CHAIN (spec))
4170    {
4171      tree id = TREE_VALUE (spec);
4172
4173      /* If the entire declaration is itself tagged as deprecated then
4174         suppress reports of deprecated items.  */
4175      if (id && TREE_DEPRECATED (id))
4176        {
4177	  if (deprecated_state != DEPRECATED_SUPPRESS)
4178	    warn_deprecated_use (id);
4179        }
4180
4181      if (id == ridpointers[(int) RID_INT])
4182	explicit_int = 1;
4183      if (id == ridpointers[(int) RID_CHAR])
4184	explicit_char = 1;
4185
4186      if (TREE_CODE (id) == IDENTIFIER_NODE && C_IS_RESERVED_WORD (id))
4187	{
4188	  enum rid i = C_RID_CODE (id);
4189	  if ((int) i <= (int) RID_LAST_MODIFIER)
4190	    {
4191	      if (i == RID_LONG && (specbits & (1 << (int) i)))
4192		{
4193		  if (longlong)
4194		    error ("`long long long' is too long for GCC");
4195		  else
4196		    {
4197		      if (pedantic && !flag_isoc99 && ! in_system_header
4198			  && warn_long_long)
4199			pedwarn ("ISO C89 does not support `long long'");
4200		      longlong = 1;
4201		    }
4202		}
4203	      else if (specbits & (1 << (int) i))
4204		pedwarn ("duplicate `%s'", IDENTIFIER_POINTER (id));
4205	      specbits |= 1 << (int) i;
4206	      goto found;
4207	    }
4208	}
4209      if (type)
4210	error ("two or more data types in declaration of `%s'", name);
4211      /* Actual typedefs come to us as TYPE_DECL nodes.  */
4212      else if (TREE_CODE (id) == TYPE_DECL)
4213	{
4214	  if (TREE_TYPE (id) == error_mark_node)
4215	    ; /* Allow the type to default to int to avoid cascading errors.  */
4216	  else
4217	    {
4218	      type = TREE_TYPE (id);
4219	      decl_attr = DECL_ATTRIBUTES (id);
4220	      typedef_decl = id;
4221	    }
4222	}
4223      /* Built-in types come as identifiers.  */
4224      else if (TREE_CODE (id) == IDENTIFIER_NODE)
4225	{
4226	  tree t = lookup_name (id);
4227	  if (TREE_TYPE (t) == error_mark_node)
4228	    ;
4229	  else if (!t || TREE_CODE (t) != TYPE_DECL)
4230	    error ("`%s' fails to be a typedef or built in type",
4231		   IDENTIFIER_POINTER (id));
4232	  else
4233	    {
4234	      type = TREE_TYPE (t);
4235	      typedef_decl = t;
4236	    }
4237	}
4238      else if (TREE_CODE (id) != ERROR_MARK)
4239	type = id;
4240
4241    found:
4242      ;
4243    }
4244
4245  typedef_type = type;
4246  if (type)
4247    size_varies = C_TYPE_VARIABLE_SIZE (type);
4248
4249  /* No type at all: default to `int', and set DEFAULTED_INT
4250     because it was not a user-defined typedef.  */
4251
4252  if (type == 0)
4253    {
4254      if ((! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4255			  | (1 << (int) RID_SIGNED)
4256			  | (1 << (int) RID_UNSIGNED)
4257			  | (1 << (int) RID_COMPLEX))))
4258	  /* Don't warn about typedef foo = bar.  */
4259	  && ! (specbits & (1 << (int) RID_TYPEDEF) && initialized)
4260	  && ! in_system_header)
4261	{
4262	  /* Issue a warning if this is an ISO C 99 program or if -Wreturn-type
4263	     and this is a function, or if -Wimplicit; prefer the former
4264	     warning since it is more explicit.  */
4265	  if ((warn_implicit_int || warn_return_type || flag_isoc99)
4266	      && funcdef_flag)
4267	    warn_about_return_type = 1;
4268	  else if (warn_implicit_int || flag_isoc99)
4269	    pedwarn_c99 ("type defaults to `int' in declaration of `%s'",
4270			 name);
4271	}
4272
4273      defaulted_int = 1;
4274      type = integer_type_node;
4275    }
4276
4277  /* Now process the modifiers that were specified
4278     and check for invalid combinations.  */
4279
4280  /* Long double is a special combination.  */
4281
4282  if ((specbits & 1 << (int) RID_LONG) && ! longlong
4283      && TYPE_MAIN_VARIANT (type) == double_type_node)
4284    {
4285      specbits &= ~(1 << (int) RID_LONG);
4286      type = long_double_type_node;
4287    }
4288
4289  /* Check all other uses of type modifiers.  */
4290
4291  if (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4292		  | (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED)))
4293    {
4294      int ok = 0;
4295
4296      if ((specbits & 1 << (int) RID_LONG)
4297	  && (specbits & 1 << (int) RID_SHORT))
4298	error ("both long and short specified for `%s'", name);
4299      else if (((specbits & 1 << (int) RID_LONG)
4300		|| (specbits & 1 << (int) RID_SHORT))
4301	       && explicit_char)
4302	error ("long or short specified with char for `%s'", name);
4303      else if (((specbits & 1 << (int) RID_LONG)
4304		|| (specbits & 1 << (int) RID_SHORT))
4305	       && TREE_CODE (type) == REAL_TYPE)
4306	{
4307	  static int already = 0;
4308
4309	  error ("long or short specified with floating type for `%s'", name);
4310	  if (! already && ! pedantic)
4311	    {
4312	      error ("the only valid combination is `long double'");
4313	      already = 1;
4314	    }
4315	}
4316      else if ((specbits & 1 << (int) RID_SIGNED)
4317	       && (specbits & 1 << (int) RID_UNSIGNED))
4318	error ("both signed and unsigned specified for `%s'", name);
4319      else if (TREE_CODE (type) != INTEGER_TYPE)
4320	error ("long, short, signed or unsigned invalid for `%s'", name);
4321      else
4322	{
4323	  ok = 1;
4324	  if (!explicit_int && !defaulted_int && !explicit_char && pedantic)
4325	    {
4326	      pedwarn ("long, short, signed or unsigned used invalidly for `%s'",
4327		       name);
4328	      if (flag_pedantic_errors)
4329		ok = 0;
4330	    }
4331	}
4332
4333      /* Discard the type modifiers if they are invalid.  */
4334      if (! ok)
4335	{
4336	  specbits &= ~((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4337			| (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED));
4338	  longlong = 0;
4339	}
4340    }
4341
4342  if ((specbits & (1 << (int) RID_COMPLEX))
4343      && TREE_CODE (type) != INTEGER_TYPE && TREE_CODE (type) != REAL_TYPE)
4344    {
4345      error ("complex invalid for `%s'", name);
4346      specbits &= ~(1 << (int) RID_COMPLEX);
4347    }
4348
4349  /* Decide whether an integer type is signed or not.
4350     Optionally treat bitfields as signed by default.  */
4351  if (specbits & 1 << (int) RID_UNSIGNED
4352      /* Traditionally, all bitfields are unsigned.  */
4353      || (bitfield && flag_traditional
4354	  && (! explicit_flag_signed_bitfields || !flag_signed_bitfields))
4355      || (bitfield && ! flag_signed_bitfields
4356	  && (explicit_int || defaulted_int || explicit_char
4357	      /* A typedef for plain `int' without `signed'
4358		 can be controlled just like plain `int'.  */
4359	      || ! (typedef_decl != 0
4360		    && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
4361	  && TREE_CODE (type) != ENUMERAL_TYPE
4362	  && !(specbits & 1 << (int) RID_SIGNED)))
4363    {
4364      if (longlong)
4365	type = long_long_unsigned_type_node;
4366      else if (specbits & 1 << (int) RID_LONG)
4367	type = long_unsigned_type_node;
4368      else if (specbits & 1 << (int) RID_SHORT)
4369	type = short_unsigned_type_node;
4370      else if (type == char_type_node)
4371	type = unsigned_char_type_node;
4372      else if (typedef_decl)
4373	type = unsigned_type (type);
4374      else
4375	type = unsigned_type_node;
4376    }
4377  else if ((specbits & 1 << (int) RID_SIGNED)
4378	   && type == char_type_node)
4379    type = signed_char_type_node;
4380  else if (longlong)
4381    type = long_long_integer_type_node;
4382  else if (specbits & 1 << (int) RID_LONG)
4383    type = long_integer_type_node;
4384  else if (specbits & 1 << (int) RID_SHORT)
4385    type = short_integer_type_node;
4386
4387  if (specbits & 1 << (int) RID_COMPLEX)
4388    {
4389      if (pedantic && !flag_isoc99)
4390	pedwarn ("ISO C89 does not support complex types");
4391      /* If we just have "complex", it is equivalent to
4392	 "complex double", but if any modifiers at all are specified it is
4393	 the complex form of TYPE.  E.g, "complex short" is
4394	 "complex short int".  */
4395
4396      if (defaulted_int && ! longlong
4397	  && ! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4398			    | (1 << (int) RID_SIGNED)
4399			    | (1 << (int) RID_UNSIGNED))))
4400	{
4401	  if (pedantic)
4402	    pedwarn ("ISO C does not support plain `complex' meaning `double complex'");
4403	  type = complex_double_type_node;
4404	}
4405      else if (type == integer_type_node)
4406	{
4407	  if (pedantic)
4408	    pedwarn ("ISO C does not support complex integer types");
4409	  type = complex_integer_type_node;
4410	}
4411      else if (type == float_type_node)
4412	type = complex_float_type_node;
4413      else if (type == double_type_node)
4414	type = complex_double_type_node;
4415      else if (type == long_double_type_node)
4416	type = complex_long_double_type_node;
4417      else
4418	{
4419	  if (pedantic)
4420	    pedwarn ("ISO C does not support complex integer types");
4421	  type = build_complex_type (type);
4422	}
4423    }
4424
4425  /* Figure out the type qualifiers for the declaration.  There are
4426     two ways a declaration can become qualified.  One is something
4427     like `const int i' where the `const' is explicit.  Another is
4428     something like `typedef const int CI; CI i' where the type of the
4429     declaration contains the `const'.  */
4430  constp = !! (specbits & 1 << (int) RID_CONST) + TYPE_READONLY (type);
4431  restrictp = !! (specbits & 1 << (int) RID_RESTRICT) + TYPE_RESTRICT (type);
4432  volatilep = !! (specbits & 1 << (int) RID_VOLATILE) + TYPE_VOLATILE (type);
4433  inlinep = !! (specbits & (1 << (int) RID_INLINE));
4434  if (constp > 1 && ! flag_isoc99)
4435    pedwarn ("duplicate `const'");
4436  if (restrictp > 1 && ! flag_isoc99)
4437    pedwarn ("duplicate `restrict'");
4438  if (volatilep > 1 && ! flag_isoc99)
4439    pedwarn ("duplicate `volatile'");
4440  if (! flag_gen_aux_info && (TYPE_QUALS (type)))
4441    type = TYPE_MAIN_VARIANT (type);
4442  type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4443		| (restrictp ? TYPE_QUAL_RESTRICT : 0)
4444		| (volatilep ? TYPE_QUAL_VOLATILE : 0));
4445
4446  /* Warn if two storage classes are given. Default to `auto'.  */
4447
4448  {
4449    int nclasses = 0;
4450
4451    if (specbits & 1 << (int) RID_AUTO) nclasses++;
4452    if (specbits & 1 << (int) RID_STATIC) nclasses++;
4453    if (specbits & 1 << (int) RID_EXTERN) nclasses++;
4454    if (specbits & 1 << (int) RID_REGISTER) nclasses++;
4455    if (specbits & 1 << (int) RID_TYPEDEF) nclasses++;
4456
4457    /* Warn about storage classes that are invalid for certain
4458       kinds of declarations (parameters, typenames, etc.).  */
4459
4460    if (nclasses > 1)
4461      error ("multiple storage classes in declaration of `%s'", name);
4462    else if (funcdef_flag
4463	     && (specbits
4464		 & ((1 << (int) RID_REGISTER)
4465		    | (1 << (int) RID_AUTO)
4466		    | (1 << (int) RID_TYPEDEF))))
4467      {
4468	if (specbits & 1 << (int) RID_AUTO
4469	    && (pedantic || current_binding_level == global_binding_level))
4470	  pedwarn ("function definition declared `auto'");
4471	if (specbits & 1 << (int) RID_REGISTER)
4472	  error ("function definition declared `register'");
4473	if (specbits & 1 << (int) RID_TYPEDEF)
4474	  error ("function definition declared `typedef'");
4475	specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
4476		      | (1 << (int) RID_AUTO));
4477      }
4478    else if (decl_context != NORMAL && nclasses > 0)
4479      {
4480	if (decl_context == PARM && specbits & 1 << (int) RID_REGISTER)
4481	  ;
4482	else
4483	  {
4484	    switch (decl_context)
4485	      {
4486	      case FIELD:
4487		error ("storage class specified for structure field `%s'",
4488		       name);
4489		break;
4490	      case PARM:
4491		error ("storage class specified for parameter `%s'", name);
4492		break;
4493	      default:
4494		error ("storage class specified for typename");
4495		break;
4496	      }
4497	    specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
4498			  | (1 << (int) RID_AUTO) | (1 << (int) RID_STATIC)
4499			  | (1 << (int) RID_EXTERN));
4500	  }
4501      }
4502    else if (specbits & 1 << (int) RID_EXTERN && initialized && ! funcdef_flag)
4503      {
4504	/* `extern' with initialization is invalid if not at top level.  */
4505	if (current_binding_level == global_binding_level)
4506	  warning ("`%s' initialized and declared `extern'", name);
4507	else
4508	  error ("`%s' has both `extern' and initializer", name);
4509      }
4510    else if (specbits & 1 << (int) RID_EXTERN && funcdef_flag
4511	     && current_binding_level != global_binding_level)
4512      error ("nested function `%s' declared `extern'", name);
4513    else if (current_binding_level == global_binding_level
4514	     && specbits & (1 << (int) RID_AUTO))
4515      error ("top-level declaration of `%s' specifies `auto'", name);
4516  }
4517
4518  /* Now figure out the structure of the declarator proper.
4519     Descend through it, creating more complex types, until we reach
4520     the declared identifier (or NULL_TREE, in an absolute declarator).  */
4521
4522  while (declarator && TREE_CODE (declarator) != IDENTIFIER_NODE)
4523    {
4524      if (type == error_mark_node)
4525	{
4526	  declarator = TREE_OPERAND (declarator, 0);
4527	  continue;
4528	}
4529
4530      /* Each level of DECLARATOR is either an ARRAY_REF (for ...[..]),
4531	 an INDIRECT_REF (for *...),
4532	 a CALL_EXPR (for ...(...)),
4533	 a TREE_LIST (for nested attributes),
4534	 an identifier (for the name being declared)
4535	 or a null pointer (for the place in an absolute declarator
4536	 where the name was omitted).
4537	 For the last two cases, we have just exited the loop.
4538
4539	 At this point, TYPE is the type of elements of an array,
4540	 or for a function to return, or for a pointer to point to.
4541	 After this sequence of ifs, TYPE is the type of the
4542	 array or function or pointer, and DECLARATOR has had its
4543	 outermost layer removed.  */
4544
4545      if (array_ptr_quals != NULL_TREE || array_parm_static)
4546	{
4547	  /* Only the innermost declarator (making a parameter be of
4548	     array type which is converted to pointer type)
4549	     may have static or type qualifiers.  */
4550	  error ("static or type qualifiers in non-parameter array declarator");
4551	  array_ptr_quals = NULL_TREE;
4552	  array_parm_static = 0;
4553	}
4554
4555      if (TREE_CODE (declarator) == TREE_LIST)
4556	{
4557	  /* We encode a declarator with embedded attributes using
4558	     a TREE_LIST.  */
4559	  tree attrs = TREE_PURPOSE (declarator);
4560	  tree inner_decl;
4561	  int attr_flags = 0;
4562	  declarator = TREE_VALUE (declarator);
4563	  inner_decl = declarator;
4564	  while (inner_decl != NULL_TREE
4565		 && TREE_CODE (inner_decl) == TREE_LIST)
4566	    inner_decl = TREE_VALUE (inner_decl);
4567	  if (inner_decl == NULL_TREE
4568	      || TREE_CODE (inner_decl) == IDENTIFIER_NODE)
4569	    attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
4570	  else if (TREE_CODE (inner_decl) == CALL_EXPR)
4571	    attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
4572	  else if (TREE_CODE (inner_decl) == ARRAY_REF)
4573	    attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
4574	  returned_attrs = decl_attributes (&type,
4575					    chainon (returned_attrs, attrs),
4576					    attr_flags);
4577	}
4578      else if (TREE_CODE (declarator) == ARRAY_REF)
4579	{
4580	  tree itype = NULL_TREE;
4581	  tree size = TREE_OPERAND (declarator, 1);
4582	  /* The index is a signed object `sizetype' bits wide.  */
4583	  tree index_type = signed_type (sizetype);
4584
4585	  array_ptr_quals = TREE_TYPE (declarator);
4586	  array_parm_static = TREE_STATIC (declarator);
4587
4588	  declarator = TREE_OPERAND (declarator, 0);
4589
4590	  /* Check for some types that there cannot be arrays of.  */
4591
4592	  if (VOID_TYPE_P (type))
4593	    {
4594	      error ("declaration of `%s' as array of voids", name);
4595	      type = error_mark_node;
4596	    }
4597
4598	  if (TREE_CODE (type) == FUNCTION_TYPE)
4599	    {
4600	      error ("declaration of `%s' as array of functions", name);
4601	      type = error_mark_node;
4602	    }
4603
4604	  if (size == error_mark_node)
4605	    type = error_mark_node;
4606
4607	  if (type == error_mark_node)
4608	    continue;
4609
4610	  /* If size was specified, set ITYPE to a range-type for that size.
4611	     Otherwise, ITYPE remains null.  finish_decl may figure it out
4612	     from an initial value.  */
4613
4614	  if (size)
4615	    {
4616	      /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue.  */
4617	      STRIP_TYPE_NOPS (size);
4618
4619	      if (! INTEGRAL_TYPE_P (TREE_TYPE (size)))
4620		{
4621		  error ("size of array `%s' has non-integer type", name);
4622		  size = integer_one_node;
4623		}
4624
4625	      if (pedantic && integer_zerop (size))
4626		pedwarn ("ISO C forbids zero-size array `%s'", name);
4627
4628	      if (TREE_CODE (size) == INTEGER_CST)
4629		{
4630		  constant_expression_warning (size);
4631		  if (tree_int_cst_sgn (size) < 0)
4632		    {
4633		      error ("size of array `%s' is negative", name);
4634		      size = integer_one_node;
4635		    }
4636		}
4637	      else
4638		{
4639		  /* Make sure the array size remains visibly nonconstant
4640		     even if it is (eg) a const variable with known value.  */
4641		  size_varies = 1;
4642
4643		  if (pedantic)
4644		    {
4645		      if (TREE_CONSTANT (size))
4646			pedwarn ("ISO C89 forbids array `%s' whose size can't be evaluated",
4647				 name);
4648		      else
4649			pedwarn ("ISO C89 forbids variable-size array `%s'",
4650				 name);
4651		    }
4652		}
4653
4654	      if (integer_zerop (size))
4655		{
4656		  /* A zero-length array cannot be represented with an
4657		     unsigned index type, which is what we'll get with
4658		     build_index_type.  Create an open-ended range instead.  */
4659		  itype = build_range_type (sizetype, size, NULL_TREE);
4660		}
4661	      else
4662		{
4663		  /* Compute the maximum valid index, that is, size - 1.
4664		     Do the calculation in index_type, so that if it is
4665		     a variable the computations will be done in the
4666		     proper mode.  */
4667	          itype = fold (build (MINUS_EXPR, index_type,
4668				       convert (index_type, size),
4669				       convert (index_type, size_one_node)));
4670
4671	          /* If that overflowed, the array is too big.
4672		     ??? While a size of INT_MAX+1 technically shouldn't
4673		     cause an overflow (because we subtract 1), the overflow
4674		     is recorded during the conversion to index_type, before
4675		     the subtraction.  Handling this case seems like an
4676		     unnecessary complication.  */
4677		  if (TREE_OVERFLOW (itype))
4678		    {
4679		      error ("size of array `%s' is too large", name);
4680		      type = error_mark_node;
4681		      continue;
4682		    }
4683
4684		  if (size_varies)
4685		    itype = variable_size (itype);
4686		  itype = build_index_type (itype);
4687		}
4688	    }
4689	  else if (decl_context == FIELD)
4690	    {
4691	      if (pedantic && !flag_isoc99 && !in_system_header)
4692		pedwarn ("ISO C89 does not support flexible array members");
4693
4694	      /* ISO C99 Flexible array members are effectively identical
4695		 to GCC's zero-length array extension.  */
4696	      itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4697	    }
4698
4699	  /* If pedantic, complain about arrays of incomplete types.  */
4700
4701	  if (pedantic && !COMPLETE_TYPE_P (type))
4702	    pedwarn ("array type has incomplete element type");
4703
4704#if 0
4705	  /* We shouldn't have a function type here at all!
4706	     Functions aren't allowed as array elements.  */
4707	  if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4708	      && (constp || volatilep))
4709	    pedwarn ("ISO C forbids const or volatile function types");
4710#endif
4711
4712	  /* Build the array type itself, then merge any constancy or
4713	     volatility into the target type.  We must do it in this order
4714	     to ensure that the TYPE_MAIN_VARIANT field of the array type
4715	     is set correctly.  */
4716
4717	  type = build_array_type (type, itype);
4718	  if (type_quals)
4719	    type = c_build_qualified_type (type, type_quals);
4720
4721	  if (size_varies)
4722	    C_TYPE_VARIABLE_SIZE (type) = 1;
4723
4724	  /* The GCC extension for zero-length arrays differs from
4725	     ISO flexible array members in that sizeof yields zero.  */
4726	  if (size && integer_zerop (size))
4727	    {
4728	      layout_type (type);
4729	      TYPE_SIZE (type) = bitsize_zero_node;
4730	      TYPE_SIZE_UNIT (type) = size_zero_node;
4731	    }
4732	  if (decl_context != PARM
4733	      && (array_ptr_quals != NULL_TREE || array_parm_static))
4734	    {
4735	      error ("static or type qualifiers in non-parameter array declarator");
4736	      array_ptr_quals = NULL_TREE;
4737	      array_parm_static = 0;
4738	    }
4739	}
4740      else if (TREE_CODE (declarator) == CALL_EXPR)
4741	{
4742	  tree arg_types;
4743
4744	  /* Declaring a function type.
4745	     Make sure we have a valid type for the function to return.  */
4746	  if (type == error_mark_node)
4747	    continue;
4748
4749	  size_varies = 0;
4750
4751	  /* Warn about some types functions can't return.  */
4752
4753	  if (TREE_CODE (type) == FUNCTION_TYPE)
4754	    {
4755	      error ("`%s' declared as function returning a function", name);
4756	      type = integer_type_node;
4757	    }
4758	  if (TREE_CODE (type) == ARRAY_TYPE)
4759	    {
4760	      error ("`%s' declared as function returning an array", name);
4761	      type = integer_type_node;
4762	    }
4763
4764#ifndef TRADITIONAL_RETURN_FLOAT
4765	  /* Traditionally, declaring return type float means double.  */
4766
4767	  if (flag_traditional && TYPE_MAIN_VARIANT (type) == float_type_node)
4768	    type = double_type_node;
4769#endif /* TRADITIONAL_RETURN_FLOAT */
4770
4771	  /* Construct the function type and go to the next
4772	     inner layer of declarator.  */
4773
4774	  arg_types = grokparms (TREE_OPERAND (declarator, 1),
4775				 funcdef_flag
4776				 /* Say it's a definition
4777				    only for the CALL_EXPR
4778				    closest to the identifier.  */
4779				 && TREE_CODE (TREE_OPERAND (declarator, 0)) == IDENTIFIER_NODE);
4780	  /* Type qualifiers before the return type of the function
4781	     qualify the return type, not the function type.  */
4782	  if (type_quals)
4783	    {
4784	      /* Type qualifiers on a function return type are normally
4785		 permitted by the standard but have no effect, so give a
4786		 warning at -W.  Qualifiers on a void return type have
4787		 meaning as a GNU extension, and are banned on function
4788		 definitions in ISO C.  FIXME: strictly we shouldn't
4789		 pedwarn for qualified void return types except on function
4790		 definitions, but not doing so could lead to the undesirable
4791		 state of a "volatile void" function return type not being
4792		 warned about, and a use of the function being compiled
4793		 with GNU semantics, with no diagnostics under -pedantic.  */
4794	      if (VOID_TYPE_P (type) && pedantic && !in_system_header)
4795		pedwarn ("ISO C forbids qualified void function return type");
4796	      else if (extra_warnings
4797		       && !(VOID_TYPE_P (type)
4798			    && type_quals == TYPE_QUAL_VOLATILE))
4799		warning ("type qualifiers ignored on function return type");
4800
4801	      type = c_build_qualified_type (type, type_quals);
4802	    }
4803	  type_quals = TYPE_UNQUALIFIED;
4804
4805	  type = build_function_type (type, arg_types);
4806	  declarator = TREE_OPERAND (declarator, 0);
4807
4808	  /* Set the TYPE_CONTEXTs for each tagged type which is local to
4809	     the formal parameter list of this FUNCTION_TYPE to point to
4810	     the FUNCTION_TYPE node itself.  */
4811
4812	  {
4813	    tree link;
4814
4815	    for (link = last_function_parm_tags;
4816		 link;
4817		 link = TREE_CHAIN (link))
4818	      TYPE_CONTEXT (TREE_VALUE (link)) = type;
4819	  }
4820	}
4821      else if (TREE_CODE (declarator) == INDIRECT_REF)
4822	{
4823	  /* Merge any constancy or volatility into the target type
4824	     for the pointer.  */
4825
4826	  if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4827	      && type_quals)
4828	    pedwarn ("ISO C forbids qualified function types");
4829	  if (type_quals)
4830	    type = c_build_qualified_type (type, type_quals);
4831	  type_quals = TYPE_UNQUALIFIED;
4832	  size_varies = 0;
4833
4834	  type = build_pointer_type (type);
4835
4836	  /* Process a list of type modifier keywords
4837	     (such as const or volatile) that were given inside the `*'.  */
4838
4839	  if (TREE_TYPE (declarator))
4840	    {
4841	      tree typemodlist;
4842	      int erred = 0;
4843
4844	      constp = 0;
4845	      volatilep = 0;
4846	      restrictp = 0;
4847	      for (typemodlist = TREE_TYPE (declarator); typemodlist;
4848		   typemodlist = TREE_CHAIN (typemodlist))
4849		{
4850		  tree qualifier = TREE_VALUE (typemodlist);
4851
4852		  if (C_IS_RESERVED_WORD (qualifier))
4853		    {
4854		      if (C_RID_CODE (qualifier) == RID_CONST)
4855			constp++;
4856		      else if (C_RID_CODE (qualifier) == RID_VOLATILE)
4857			volatilep++;
4858		      else if (C_RID_CODE (qualifier) == RID_RESTRICT)
4859			restrictp++;
4860		      else
4861			erred++;
4862		    }
4863		  else
4864		    erred++;
4865		}
4866
4867	      if (erred)
4868		error ("invalid type modifier within pointer declarator");
4869	      if (constp > 1 && ! flag_isoc99)
4870		pedwarn ("duplicate `const'");
4871	      if (volatilep > 1 && ! flag_isoc99)
4872		pedwarn ("duplicate `volatile'");
4873	      if (restrictp > 1 && ! flag_isoc99)
4874		pedwarn ("duplicate `restrict'");
4875
4876	      type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4877			    | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4878			    | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4879	    }
4880
4881	  declarator = TREE_OPERAND (declarator, 0);
4882	}
4883      else
4884	abort ();
4885
4886    }
4887
4888  /* Now TYPE has the actual type.  */
4889
4890  /* Did array size calculations overflow?  */
4891
4892  if (TREE_CODE (type) == ARRAY_TYPE
4893      && COMPLETE_TYPE_P (type)
4894      && TREE_OVERFLOW (TYPE_SIZE (type)))
4895    {
4896      error ("size of array `%s' is too large", name);
4897      /* If we proceed with the array type as it is, we'll eventually
4898	 crash in tree_low_cst().  */
4899      type = error_mark_node;
4900    }
4901
4902  /* If this is declaring a typedef name, return a TYPE_DECL.  */
4903
4904  if (specbits & (1 << (int) RID_TYPEDEF))
4905    {
4906      tree decl;
4907      /* Note that the grammar rejects storage classes
4908	 in typenames, fields or parameters */
4909      if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4910	  && type_quals)
4911	pedwarn ("ISO C forbids qualified function types");
4912      if (type_quals)
4913	type = c_build_qualified_type (type, type_quals);
4914      decl = build_decl (TYPE_DECL, declarator, type);
4915      if ((specbits & (1 << (int) RID_SIGNED))
4916	  || (typedef_decl && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
4917	C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
4918      decl_attributes (&decl, returned_attrs, 0);
4919      return decl;
4920    }
4921
4922  /* Detect the case of an array type of unspecified size
4923     which came, as such, direct from a typedef name.
4924     We must copy the type, so that each identifier gets
4925     a distinct type, so that each identifier's size can be
4926     controlled separately by its own initializer.  */
4927
4928  if (type != 0 && typedef_type != 0
4929      && TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == 0
4930      && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (typedef_type))
4931    {
4932      type = build_array_type (TREE_TYPE (type), 0);
4933      if (size_varies)
4934	C_TYPE_VARIABLE_SIZE (type) = 1;
4935    }
4936
4937  /* If this is a type name (such as, in a cast or sizeof),
4938     compute the type and return it now.  */
4939
4940  if (decl_context == TYPENAME)
4941    {
4942      /* Note that the grammar rejects storage classes
4943	 in typenames, fields or parameters */
4944      if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4945	  && type_quals)
4946	pedwarn ("ISO C forbids const or volatile function types");
4947      if (type_quals)
4948	type = c_build_qualified_type (type, type_quals);
4949      decl_attributes (&type, returned_attrs, 0);
4950      return type;
4951    }
4952
4953  /* Aside from typedefs and type names (handle above),
4954     `void' at top level (not within pointer)
4955     is allowed only in public variables.
4956     We don't complain about parms either, but that is because
4957     a better error message can be made later.  */
4958
4959  if (VOID_TYPE_P (type) && decl_context != PARM
4960      && ! ((decl_context != FIELD && TREE_CODE (type) != FUNCTION_TYPE)
4961	    && ((specbits & (1 << (int) RID_EXTERN))
4962		|| (current_binding_level == global_binding_level
4963		    && !(specbits
4964			 & ((1 << (int) RID_STATIC) | (1 << (int) RID_REGISTER)))))))
4965    {
4966      error ("variable or field `%s' declared void", name);
4967      type = integer_type_node;
4968    }
4969
4970  /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
4971     or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE.  */
4972
4973  {
4974    tree decl;
4975
4976    if (decl_context == PARM)
4977      {
4978	tree type_as_written;
4979	tree promoted_type;
4980
4981	/* A parameter declared as an array of T is really a pointer to T.
4982	   One declared as a function is really a pointer to a function.  */
4983
4984	if (TREE_CODE (type) == ARRAY_TYPE)
4985	  {
4986	    /* Transfer const-ness of array into that of type pointed to.  */
4987	    type = TREE_TYPE (type);
4988	    if (type_quals)
4989	      type = c_build_qualified_type (type, type_quals);
4990	    type = build_pointer_type (type);
4991	    type_quals = TYPE_UNQUALIFIED;
4992	    if (array_ptr_quals)
4993	      {
4994		tree new_ptr_quals, new_ptr_attrs;
4995		int erred = 0;
4996		split_specs_attrs (array_ptr_quals, &new_ptr_quals, &new_ptr_attrs);
4997		/* We don't yet implement attributes in this context.  */
4998		if (new_ptr_attrs != NULL_TREE)
4999		  warning ("attributes in parameter array declarator ignored");
5000
5001		constp = 0;
5002		volatilep = 0;
5003		restrictp = 0;
5004		for (; new_ptr_quals; new_ptr_quals = TREE_CHAIN (new_ptr_quals))
5005		  {
5006		    tree qualifier = TREE_VALUE (new_ptr_quals);
5007
5008		    if (C_IS_RESERVED_WORD (qualifier))
5009		      {
5010			if (C_RID_CODE (qualifier) == RID_CONST)
5011			  constp++;
5012			else if (C_RID_CODE (qualifier) == RID_VOLATILE)
5013			  volatilep++;
5014			else if (C_RID_CODE (qualifier) == RID_RESTRICT)
5015			  restrictp++;
5016			else
5017			  erred++;
5018		      }
5019		    else
5020		      erred++;
5021		  }
5022
5023		if (erred)
5024		  error ("invalid type modifier within array declarator");
5025
5026		type_quals = ((constp ? TYPE_QUAL_CONST : 0)
5027			      | (restrictp ? TYPE_QUAL_RESTRICT : 0)
5028			      | (volatilep ? TYPE_QUAL_VOLATILE : 0));
5029	      }
5030	    size_varies = 0;
5031	  }
5032	else if (TREE_CODE (type) == FUNCTION_TYPE)
5033	  {
5034	    if (pedantic && type_quals)
5035	      pedwarn ("ISO C forbids qualified function types");
5036	    if (type_quals)
5037	      type = c_build_qualified_type (type, type_quals);
5038	    type = build_pointer_type (type);
5039	    type_quals = TYPE_UNQUALIFIED;
5040	  }
5041	else if (type_quals)
5042	  type = c_build_qualified_type (type, type_quals);
5043
5044	type_as_written = type;
5045
5046	decl = build_decl (PARM_DECL, declarator, type);
5047	if (size_varies)
5048	  C_DECL_VARIABLE_SIZE (decl) = 1;
5049
5050	/* Compute the type actually passed in the parmlist,
5051	   for the case where there is no prototype.
5052	   (For example, shorts and chars are passed as ints.)
5053	   When there is a prototype, this is overridden later.  */
5054
5055	if (type == error_mark_node)
5056	  promoted_type = type;
5057	else
5058	  {
5059	    promoted_type = simple_type_promotes_to (type);
5060	    if (! promoted_type)
5061	      promoted_type = type;
5062	  }
5063
5064	DECL_ARG_TYPE (decl) = promoted_type;
5065	DECL_ARG_TYPE_AS_WRITTEN (decl) = type_as_written;
5066      }
5067    else if (decl_context == FIELD)
5068      {
5069	/* Structure field.  It may not be a function.  */
5070
5071	if (TREE_CODE (type) == FUNCTION_TYPE)
5072	  {
5073	    error ("field `%s' declared as a function", name);
5074	    type = build_pointer_type (type);
5075	  }
5076	else if (TREE_CODE (type) != ERROR_MARK
5077	         && !COMPLETE_OR_UNBOUND_ARRAY_TYPE_P (type))
5078	  {
5079	    error ("field `%s' has incomplete type", name);
5080	    type = error_mark_node;
5081	  }
5082	/* Move type qualifiers down to element of an array.  */
5083	if (TREE_CODE (type) == ARRAY_TYPE && type_quals)
5084	  {
5085	    type = build_array_type (c_build_qualified_type (TREE_TYPE (type),
5086							     type_quals),
5087				     TYPE_DOMAIN (type));
5088#if 0
5089	    /* Leave the field const or volatile as well.  */
5090	    type_quals = TYPE_UNQUALIFIED;
5091#endif
5092	  }
5093	decl = build_decl (FIELD_DECL, declarator, type);
5094	DECL_NONADDRESSABLE_P (decl) = bitfield;
5095
5096	if (size_varies)
5097	  C_DECL_VARIABLE_SIZE (decl) = 1;
5098      }
5099    else if (TREE_CODE (type) == FUNCTION_TYPE)
5100      {
5101	/* Every function declaration is "external"
5102	   except for those which are inside a function body
5103	   in which `auto' is used.
5104	   That is a case not specified by ANSI C,
5105	   and we use it for forward declarations for nested functions.  */
5106	int extern_ref = (!(specbits & (1 << (int) RID_AUTO))
5107			  || current_binding_level == global_binding_level);
5108
5109	if (specbits & (1 << (int) RID_AUTO)
5110	    && (pedantic || current_binding_level == global_binding_level))
5111	  pedwarn ("invalid storage class for function `%s'", name);
5112	if (specbits & (1 << (int) RID_REGISTER))
5113	  error ("invalid storage class for function `%s'", name);
5114	/* Function declaration not at top level.
5115	   Storage classes other than `extern' are not allowed
5116	   and `extern' makes no difference.  */
5117	if (current_binding_level != global_binding_level
5118	    && (specbits & ((1 << (int) RID_STATIC) | (1 << (int) RID_INLINE)))
5119	    && pedantic)
5120	  pedwarn ("invalid storage class for function `%s'", name);
5121
5122	decl = build_decl (FUNCTION_DECL, declarator, type);
5123	decl = build_decl_attribute_variant (decl, decl_attr);
5124
5125	DECL_LANG_SPECIFIC (decl) = (struct lang_decl *)
5126	  ggc_alloc_cleared (sizeof (struct lang_decl));
5127
5128	if (pedantic && type_quals && ! DECL_IN_SYSTEM_HEADER (decl))
5129	  pedwarn ("ISO C forbids qualified function types");
5130
5131	/* GNU C interprets a `volatile void' return type to indicate
5132	   that the function does not return.  */
5133	if ((type_quals & TYPE_QUAL_VOLATILE)
5134	    && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
5135	  warning ("`noreturn' function returns non-void value");
5136
5137	if (extern_ref)
5138	  DECL_EXTERNAL (decl) = 1;
5139	/* Record absence of global scope for `static' or `auto'.  */
5140	TREE_PUBLIC (decl)
5141	  = !(specbits & ((1 << (int) RID_STATIC) | (1 << (int) RID_AUTO)));
5142
5143	if (defaulted_int)
5144	  C_FUNCTION_IMPLICIT_INT (decl) = 1;
5145
5146	/* Record presence of `inline', if it is reasonable.  */
5147	if (MAIN_NAME_P (declarator))
5148	  {
5149	    if (inlinep)
5150	      warning ("cannot inline function `main'");
5151	  }
5152	else if (inlinep)
5153	  {
5154	    /* Assume that otherwise the function can be inlined.  */
5155	    DECL_DECLARED_INLINE_P (decl) = 1;
5156
5157	    /* Do not mark bare declarations as DECL_INLINE.  Doing so
5158	       in the presence of multiple declarations can result in
5159	       the abstract origin pointing between the declarations,
5160	       which will confuse dwarf2out.  */
5161	    if (initialized)
5162	      {
5163		DECL_INLINE (decl) = 1;
5164		if (specbits & (1 << (int) RID_EXTERN))
5165		  current_extern_inline = 1;
5166	      }
5167	  }
5168	/* If -finline-functions, assume it can be inlined.  This does
5169	   two things: let the function be deferred until it is actually
5170	   needed, and let dwarf2 know that the function is inlinable.  */
5171	else if (flag_inline_trees == 2 && initialized)
5172	  {
5173	    DECL_INLINE (decl) = 1;
5174	    DECL_DECLARED_INLINE_P (decl) = 0;
5175	  }
5176      }
5177    else
5178      {
5179	/* It's a variable.  */
5180	/* An uninitialized decl with `extern' is a reference.  */
5181	int extern_ref = !initialized && (specbits & (1 << (int) RID_EXTERN));
5182
5183	/* Move type qualifiers down to element of an array.  */
5184	if (TREE_CODE (type) == ARRAY_TYPE && type_quals)
5185	  {
5186	    int saved_align = TYPE_ALIGN(type);
5187	    type = build_array_type (c_build_qualified_type (TREE_TYPE (type),
5188							     type_quals),
5189				     TYPE_DOMAIN (type));
5190	    TYPE_ALIGN (type) = saved_align;
5191#if 0 /* Leave the variable const or volatile as well.  */
5192	    type_quals = TYPE_UNQUALIFIED;
5193#endif
5194	  }
5195	else if (type_quals)
5196	  type = c_build_qualified_type (type, type_quals);
5197
5198	decl = build_decl (VAR_DECL, declarator, type);
5199	if (size_varies)
5200	  C_DECL_VARIABLE_SIZE (decl) = 1;
5201
5202	if (inlinep)
5203	  pedwarn_with_decl (decl, "variable `%s' declared `inline'");
5204
5205	DECL_EXTERNAL (decl) = extern_ref;
5206	/* At top level, the presence of a `static' or `register' storage
5207	   class specifier, or the absence of all storage class specifiers
5208	   makes this declaration a definition (perhaps tentative).  Also,
5209	   the absence of both `static' and `register' makes it public.  */
5210	if (current_binding_level == global_binding_level)
5211	  {
5212	    TREE_PUBLIC (decl)
5213	      = !(specbits
5214		  & ((1 << (int) RID_STATIC) | (1 << (int) RID_REGISTER)));
5215	    TREE_STATIC (decl) = ! DECL_EXTERNAL (decl);
5216	  }
5217	/* Not at top level, only `static' makes a static definition.  */
5218	else
5219	  {
5220	    TREE_STATIC (decl) = (specbits & (1 << (int) RID_STATIC)) != 0;
5221	    TREE_PUBLIC (decl) = DECL_EXTERNAL (decl);
5222	  }
5223      }
5224
5225    /* Record `register' declaration for warnings on &
5226       and in case doing stupid register allocation.  */
5227
5228    if (specbits & (1 << (int) RID_REGISTER))
5229      DECL_REGISTER (decl) = 1;
5230
5231    /* Record constancy and volatility.  */
5232    c_apply_type_quals_to_decl (type_quals, decl);
5233
5234    /* If a type has volatile components, it should be stored in memory.
5235       Otherwise, the fact that those components are volatile
5236       will be ignored, and would even crash the compiler.  */
5237    if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (decl)))
5238      mark_addressable (decl);
5239
5240    decl_attributes (&decl, returned_attrs, 0);
5241
5242    return decl;
5243  }
5244}
5245
5246/* Decode the parameter-list info for a function type or function definition.
5247   The argument is the value returned by `get_parm_info' (or made in parse.y
5248   if there is an identifier list instead of a parameter decl list).
5249   These two functions are separate because when a function returns
5250   or receives functions then each is called multiple times but the order
5251   of calls is different.  The last call to `grokparms' is always the one
5252   that contains the formal parameter names of a function definition.
5253
5254   Store in `last_function_parms' a chain of the decls of parms.
5255   Also store in `last_function_parm_tags' a chain of the struct, union,
5256   and enum tags declared among the parms.
5257
5258   Return a list of arg types to use in the FUNCTION_TYPE for this function.
5259
5260   FUNCDEF_FLAG is nonzero for a function definition, 0 for
5261   a mere declaration.  A nonempty identifier-list gets an error message
5262   when FUNCDEF_FLAG is zero.  */
5263
5264static tree
5265grokparms (parms_info, funcdef_flag)
5266     tree parms_info;
5267     int funcdef_flag;
5268{
5269  tree first_parm = TREE_CHAIN (parms_info);
5270
5271  last_function_parms = TREE_PURPOSE (parms_info);
5272  last_function_parm_tags = TREE_VALUE (parms_info);
5273
5274  if (warn_strict_prototypes && first_parm == 0 && !funcdef_flag
5275      && !in_system_header)
5276    warning ("function declaration isn't a prototype");
5277
5278  if (first_parm != 0
5279      && TREE_CODE (TREE_VALUE (first_parm)) == IDENTIFIER_NODE)
5280    {
5281      if (! funcdef_flag)
5282	pedwarn ("parameter names (without types) in function declaration");
5283
5284      last_function_parms = first_parm;
5285      return 0;
5286    }
5287  else
5288    {
5289      tree parm;
5290      tree typelt;
5291      /* We no longer test FUNCDEF_FLAG.
5292	 If the arg types are incomplete in a declaration,
5293	 they must include undefined tags.
5294	 These tags can never be defined in the scope of the declaration,
5295	 so the types can never be completed,
5296	 and no call can be compiled successfully.  */
5297#if 0
5298      /* In a fcn definition, arg types must be complete.  */
5299      if (funcdef_flag)
5300#endif
5301	for (parm = last_function_parms, typelt = first_parm;
5302	     parm;
5303	     parm = TREE_CHAIN (parm))
5304	  /* Skip over any enumeration constants declared here.  */
5305	  if (TREE_CODE (parm) == PARM_DECL)
5306	    {
5307	      /* Barf if the parameter itself has an incomplete type.  */
5308	      tree type = TREE_VALUE (typelt);
5309	      if (type == error_mark_node)
5310		continue;
5311	      if (!COMPLETE_TYPE_P (type))
5312		{
5313		  if (funcdef_flag && DECL_NAME (parm) != 0)
5314		    error ("parameter `%s' has incomplete type",
5315			   IDENTIFIER_POINTER (DECL_NAME (parm)));
5316		  else
5317		    warning ("parameter has incomplete type");
5318		  if (funcdef_flag)
5319		    {
5320		      TREE_VALUE (typelt) = error_mark_node;
5321		      TREE_TYPE (parm) = error_mark_node;
5322		    }
5323		}
5324#if 0
5325	      /* This has been replaced by parm_tags_warning, which
5326		 uses a more accurate criterion for what to warn
5327		 about.  */
5328	      else
5329		{
5330		  /* Now warn if is a pointer to an incomplete type.  */
5331		  while (TREE_CODE (type) == POINTER_TYPE
5332			 || TREE_CODE (type) == REFERENCE_TYPE)
5333		    type = TREE_TYPE (type);
5334		  type = TYPE_MAIN_VARIANT (type);
5335		  if (!COMPLETE_TYPE_P (type))
5336		    {
5337		      if (DECL_NAME (parm) != 0)
5338			warning ("parameter `%s' points to incomplete type",
5339				 IDENTIFIER_POINTER (DECL_NAME (parm)));
5340		      else
5341			warning ("parameter points to incomplete type");
5342		    }
5343		}
5344#endif
5345	      typelt = TREE_CHAIN (typelt);
5346	    }
5347
5348      return first_parm;
5349    }
5350}
5351
5352/* Return a tree_list node with info on a parameter list just parsed.
5353   The TREE_PURPOSE is a chain of decls of those parms.
5354   The TREE_VALUE is a list of structure, union and enum tags defined.
5355   The TREE_CHAIN is a list of argument types to go in the FUNCTION_TYPE.
5356   This tree_list node is later fed to `grokparms'.
5357
5358   VOID_AT_END nonzero means append `void' to the end of the type-list.
5359   Zero means the parmlist ended with an ellipsis so don't append `void'.  */
5360
5361tree
5362get_parm_info (void_at_end)
5363     int void_at_end;
5364{
5365  tree decl, t;
5366  tree types = 0;
5367  int erred = 0;
5368  tree tags = gettags ();
5369  tree parms = getdecls ();
5370  tree new_parms = 0;
5371  tree order = current_binding_level->parm_order;
5372
5373  /* Just `void' (and no ellipsis) is special.  There are really no parms.
5374     But if the `void' is qualified (by `const' or `volatile') or has a
5375     storage class specifier (`register'), then the behavior is undefined;
5376     by not counting it as the special case of `void' we will cause an
5377     error later.  Typedefs for `void' are OK (see DR#157).  */
5378  if (void_at_end && parms != 0
5379      && TREE_CHAIN (parms) == 0
5380      && VOID_TYPE_P (TREE_TYPE (parms))
5381      && ! TREE_THIS_VOLATILE (parms)
5382      && ! TREE_READONLY (parms)
5383      && ! DECL_REGISTER (parms)
5384      && DECL_NAME (parms) == 0)
5385    {
5386      parms = NULL_TREE;
5387      storedecls (NULL_TREE);
5388      return tree_cons (NULL_TREE, NULL_TREE,
5389			tree_cons (NULL_TREE, void_type_node, NULL_TREE));
5390    }
5391
5392  /* Extract enumerator values and other non-parms declared with the parms.
5393     Likewise any forward parm decls that didn't have real parm decls.  */
5394  for (decl = parms; decl;)
5395    {
5396      tree next = TREE_CHAIN (decl);
5397
5398      if (TREE_CODE (decl) != PARM_DECL)
5399	{
5400	  TREE_CHAIN (decl) = new_parms;
5401	  new_parms = decl;
5402	}
5403      else if (TREE_ASM_WRITTEN (decl))
5404	{
5405	  error_with_decl (decl,
5406			   "parameter `%s' has just a forward declaration");
5407	  TREE_CHAIN (decl) = new_parms;
5408	  new_parms = decl;
5409	}
5410      decl = next;
5411    }
5412
5413  /* Put the parm decls back in the order they were in in the parm list.  */
5414  for (t = order; t; t = TREE_CHAIN (t))
5415    {
5416      if (TREE_CHAIN (t))
5417	TREE_CHAIN (TREE_VALUE (t)) = TREE_VALUE (TREE_CHAIN (t));
5418      else
5419	TREE_CHAIN (TREE_VALUE (t)) = 0;
5420    }
5421
5422  new_parms = chainon (order ? nreverse (TREE_VALUE (order)) : 0,
5423		       new_parms);
5424
5425  /* Store the parmlist in the binding level since the old one
5426     is no longer a valid list.  (We have changed the chain pointers.)  */
5427  storedecls (new_parms);
5428
5429  for (decl = new_parms; decl; decl = TREE_CHAIN (decl))
5430    /* There may also be declarations for enumerators if an enumeration
5431       type is declared among the parms.  Ignore them here.  */
5432    if (TREE_CODE (decl) == PARM_DECL)
5433      {
5434	/* Since there is a prototype,
5435	   args are passed in their declared types.  */
5436	tree type = TREE_TYPE (decl);
5437	DECL_ARG_TYPE (decl) = type;
5438	if (PROMOTE_PROTOTYPES
5439	    && INTEGRAL_TYPE_P (type)
5440	    && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
5441	  DECL_ARG_TYPE (decl) = integer_type_node;
5442
5443	types = tree_cons (NULL_TREE, TREE_TYPE (decl), types);
5444	if (VOID_TYPE_P (TREE_VALUE (types)) && ! erred
5445	    && DECL_NAME (decl) == 0)
5446	  {
5447	    error ("`void' in parameter list must be the entire list");
5448	    erred = 1;
5449	  }
5450      }
5451
5452  if (void_at_end)
5453    return tree_cons (new_parms, tags,
5454		      nreverse (tree_cons (NULL_TREE, void_type_node, types)));
5455
5456  return tree_cons (new_parms, tags, nreverse (types));
5457}
5458
5459/* At end of parameter list, warn about any struct, union or enum tags
5460   defined within.  Do so because these types cannot ever become complete.  */
5461
5462void
5463parmlist_tags_warning ()
5464{
5465  tree elt;
5466  static int already;
5467
5468  for (elt = current_binding_level->tags; elt; elt = TREE_CHAIN (elt))
5469    {
5470      enum tree_code code = TREE_CODE (TREE_VALUE (elt));
5471      /* An anonymous union parm type is meaningful as a GNU extension.
5472	 So don't warn for that.  */
5473      if (code == UNION_TYPE && TREE_PURPOSE (elt) == 0 && !pedantic)
5474	continue;
5475      if (TREE_PURPOSE (elt) != 0)
5476        {
5477          if (code == RECORD_TYPE)
5478            warning ("`struct %s' declared inside parameter list",
5479                     IDENTIFIER_POINTER (TREE_PURPOSE (elt)));
5480          else if (code == UNION_TYPE)
5481            warning ("`union %s' declared inside parameter list",
5482                     IDENTIFIER_POINTER (TREE_PURPOSE (elt)));
5483          else
5484            warning ("`enum %s' declared inside parameter list",
5485                     IDENTIFIER_POINTER (TREE_PURPOSE (elt)));
5486        }
5487      else
5488	{
5489	  /* For translation these need to be separate warnings */
5490	  if (code == RECORD_TYPE)
5491	    warning ("anonymous struct declared inside parameter list");
5492	  else if (code == UNION_TYPE)
5493	    warning ("anonymous union declared inside parameter list");
5494	  else
5495	    warning ("anonymous enum declared inside parameter list");
5496	}
5497      if (! already)
5498	{
5499	  warning ("its scope is only this definition or declaration, which is probably not what you want");
5500	  already = 1;
5501	}
5502    }
5503}
5504
5505/* Get the struct, enum or union (CODE says which) with tag NAME.
5506   Define the tag as a forward-reference if it is not defined.  */
5507
5508tree
5509xref_tag (code, name)
5510     enum tree_code code;
5511     tree name;
5512{
5513  /* If a cross reference is requested, look up the type
5514     already defined for this tag and return it.  */
5515
5516  tree ref = lookup_tag (code, name, current_binding_level, 0);
5517  /* If this is the right type of tag, return what we found.
5518     (This reference will be shadowed by shadow_tag later if appropriate.)
5519     If this is the wrong type of tag, do not return it.  If it was the
5520     wrong type in the same binding level, we will have had an error
5521     message already; if in a different binding level and declaring
5522     a name, pending_xref_error will give an error message; but if in a
5523     different binding level and not declaring a name, this tag should
5524     shadow the previous declaration of a different type of tag, and
5525     this would not work properly if we return the reference found.
5526     (For example, with "struct foo" in an outer scope, "union foo;"
5527     must shadow that tag with a new one of union type.)  */
5528  if (ref && TREE_CODE (ref) == code)
5529    return ref;
5530
5531  /* If no such tag is yet defined, create a forward-reference node
5532     and record it as the "definition".
5533     When a real declaration of this type is found,
5534     the forward-reference will be altered into a real type.  */
5535
5536  ref = make_node (code);
5537  if (code == ENUMERAL_TYPE)
5538    {
5539      /* Give the type a default layout like unsigned int
5540	 to avoid crashing if it does not get defined.  */
5541      TYPE_MODE (ref) = TYPE_MODE (unsigned_type_node);
5542      TYPE_ALIGN (ref) = TYPE_ALIGN (unsigned_type_node);
5543      TYPE_USER_ALIGN (ref) = 0;
5544      TREE_UNSIGNED (ref) = 1;
5545      TYPE_PRECISION (ref) = TYPE_PRECISION (unsigned_type_node);
5546      TYPE_MIN_VALUE (ref) = TYPE_MIN_VALUE (unsigned_type_node);
5547      TYPE_MAX_VALUE (ref) = TYPE_MAX_VALUE (unsigned_type_node);
5548    }
5549
5550  pushtag (name, ref);
5551
5552  return ref;
5553}
5554
5555/* Make sure that the tag NAME is defined *in the current binding level*
5556   at least as a forward reference.
5557   CODE says which kind of tag NAME ought to be.  */
5558
5559tree
5560start_struct (code, name)
5561     enum tree_code code;
5562     tree name;
5563{
5564  /* If there is already a tag defined at this binding level
5565     (as a forward reference), just return it.  */
5566
5567  tree ref = 0;
5568
5569  if (name != 0)
5570    ref = lookup_tag (code, name, current_binding_level, 1);
5571  if (ref && TREE_CODE (ref) == code)
5572    {
5573      C_TYPE_BEING_DEFINED (ref) = 1;
5574      TYPE_PACKED (ref) = flag_pack_struct;
5575      if (TYPE_FIELDS (ref))
5576        {
5577	  if (code == UNION_TYPE)
5578	    error ("redefinition of `union %s'",
5579		   IDENTIFIER_POINTER (name));
5580          else
5581	    error ("redefinition of `struct %s'",
5582		   IDENTIFIER_POINTER (name));
5583	}
5584
5585      return ref;
5586    }
5587
5588  /* Otherwise create a forward-reference just so the tag is in scope.  */
5589
5590  ref = make_node (code);
5591  pushtag (name, ref);
5592  C_TYPE_BEING_DEFINED (ref) = 1;
5593  TYPE_PACKED (ref) = flag_pack_struct;
5594  return ref;
5595}
5596
5597/* Process the specs, declarator (NULL if omitted) and width (NULL if omitted)
5598   of a structure component, returning a FIELD_DECL node.
5599   WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node.
5600
5601   This is done during the parsing of the struct declaration.
5602   The FIELD_DECL nodes are chained together and the lot of them
5603   are ultimately passed to `build_struct' to make the RECORD_TYPE node.  */
5604
5605tree
5606grokfield (filename, line, declarator, declspecs, width)
5607     const char *filename ATTRIBUTE_UNUSED;
5608     int line ATTRIBUTE_UNUSED;
5609     tree declarator, declspecs, width;
5610{
5611  tree value;
5612
5613  if (declarator == NULL_TREE && width == NULL_TREE)
5614    {
5615      /* This is an unnamed decl.  We only support unnamed
5616	 structs/unions, so check for other things and refuse them.  */
5617      if (TREE_CODE (TREE_VALUE (declspecs)) != RECORD_TYPE
5618	  && TREE_CODE (TREE_VALUE (declspecs)) != UNION_TYPE)
5619	{
5620	  error ("unnamed fields of type other than struct or union are not allowed");
5621	  return NULL_TREE;
5622	}
5623    }
5624
5625  value = grokdeclarator (declarator, declspecs, width ? BITFIELD : FIELD, 0);
5626
5627  finish_decl (value, NULL_TREE, NULL_TREE);
5628  DECL_INITIAL (value) = width;
5629
5630  maybe_objc_check_decl (value);
5631  return value;
5632}
5633
5634/* Fill in the fields of a RECORD_TYPE or UNION_TYPE node, T.
5635   FIELDLIST is a chain of FIELD_DECL nodes for the fields.
5636   ATTRIBUTES are attributes to be applied to the structure.  */
5637
5638tree
5639finish_struct (t, fieldlist, attributes)
5640     tree t;
5641     tree fieldlist;
5642     tree attributes;
5643{
5644  tree x;
5645  int toplevel = global_binding_level == current_binding_level;
5646  int saw_named_field;
5647
5648  /* If this type was previously laid out as a forward reference,
5649     make sure we lay it out again.  */
5650
5651  TYPE_SIZE (t) = 0;
5652
5653  decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5654
5655  /* Nameless union parm types are useful as GCC extension.  */
5656  if (! (TREE_CODE (t) == UNION_TYPE && TYPE_NAME (t) == 0) && !pedantic)
5657    /* Otherwise, warn about any struct or union def. in parmlist.  */
5658    if (in_parm_level_p ())
5659      {
5660	if (pedantic)
5661	  pedwarn ("%s defined inside parms",
5662		   TREE_CODE (t) == UNION_TYPE ? _("union") : _("structure"));
5663	else if (! flag_traditional)
5664	  warning ("%s defined inside parms",
5665		   TREE_CODE (t) == UNION_TYPE ? _("union") : _("structure"));
5666      }
5667
5668  if (pedantic)
5669    {
5670      for (x = fieldlist; x; x = TREE_CHAIN (x))
5671	if (DECL_NAME (x) != 0)
5672	  break;
5673
5674      if (x == 0)
5675	pedwarn ("%s has no %s",
5676		 TREE_CODE (t) == UNION_TYPE ? _("union") : _("struct"),
5677		 fieldlist ? _("named members") : _("members"));
5678    }
5679
5680  /* Install struct as DECL_CONTEXT of each field decl.
5681     Also process specified field sizes,m which is found in the DECL_INITIAL.
5682     Store 0 there, except for ": 0" fields (so we can find them
5683     and delete them, below).  */
5684
5685  saw_named_field = 0;
5686  for (x = fieldlist; x; x = TREE_CHAIN (x))
5687    {
5688      DECL_CONTEXT (x) = t;
5689      DECL_PACKED (x) |= TYPE_PACKED (t);
5690
5691      /* If any field is const, the structure type is pseudo-const.  */
5692      if (TREE_READONLY (x))
5693	C_TYPE_FIELDS_READONLY (t) = 1;
5694      else
5695	{
5696	  /* A field that is pseudo-const makes the structure likewise.  */
5697	  tree t1 = TREE_TYPE (x);
5698	  while (TREE_CODE (t1) == ARRAY_TYPE)
5699	    t1 = TREE_TYPE (t1);
5700	  if ((TREE_CODE (t1) == RECORD_TYPE || TREE_CODE (t1) == UNION_TYPE)
5701	      && C_TYPE_FIELDS_READONLY (t1))
5702	    C_TYPE_FIELDS_READONLY (t) = 1;
5703	}
5704
5705      /* Any field that is volatile means variables of this type must be
5706	 treated in some ways as volatile.  */
5707      if (TREE_THIS_VOLATILE (x))
5708	C_TYPE_FIELDS_VOLATILE (t) = 1;
5709
5710      /* Any field of nominal variable size implies structure is too.  */
5711      if (C_DECL_VARIABLE_SIZE (x))
5712	C_TYPE_VARIABLE_SIZE (t) = 1;
5713
5714      /* Detect invalid nested redefinition.  */
5715      if (TREE_TYPE (x) == t)
5716	error ("nested redefinition of `%s'",
5717	       IDENTIFIER_POINTER (TYPE_NAME (t)));
5718
5719      /* Detect invalid bit-field size.  */
5720      if (DECL_INITIAL (x))
5721	STRIP_NOPS (DECL_INITIAL (x));
5722      if (DECL_INITIAL (x))
5723	{
5724	  if (TREE_CODE (DECL_INITIAL (x)) == INTEGER_CST)
5725	    constant_expression_warning (DECL_INITIAL (x));
5726	  else
5727	    {
5728	      error_with_decl (x,
5729			       "bit-field `%s' width not an integer constant");
5730	      DECL_INITIAL (x) = NULL;
5731	    }
5732	}
5733
5734      /* Detect invalid bit-field type.  */
5735      if (DECL_INITIAL (x)
5736	  && TREE_CODE (TREE_TYPE (x)) != INTEGER_TYPE
5737	  && TREE_CODE (TREE_TYPE (x)) != BOOLEAN_TYPE
5738	  && TREE_CODE (TREE_TYPE (x)) != ENUMERAL_TYPE)
5739	{
5740	  error_with_decl (x, "bit-field `%s' has invalid type");
5741	  DECL_INITIAL (x) = NULL;
5742	}
5743
5744      if (DECL_INITIAL (x) && pedantic
5745	  && TYPE_MAIN_VARIANT (TREE_TYPE (x)) != integer_type_node
5746	  && TYPE_MAIN_VARIANT (TREE_TYPE (x)) != unsigned_type_node
5747	  && TYPE_MAIN_VARIANT (TREE_TYPE (x)) != c_bool_type_node
5748	  /* Accept an enum that's equivalent to int or unsigned int.  */
5749	  && !(TREE_CODE (TREE_TYPE (x)) == ENUMERAL_TYPE
5750	       && (TYPE_PRECISION (TREE_TYPE (x))
5751		   == TYPE_PRECISION (integer_type_node))))
5752	pedwarn_with_decl (x, "bit-field `%s' type invalid in ISO C");
5753
5754      /* Detect and ignore out of range field width and process valid
5755	 field widths.  */
5756      if (DECL_INITIAL (x))
5757	{
5758	  int max_width
5759	    = (TYPE_MAIN_VARIANT (TREE_TYPE (x)) == c_bool_type_node
5760	       ? CHAR_TYPE_SIZE : TYPE_PRECISION (TREE_TYPE (x)));
5761
5762	  if (tree_int_cst_sgn (DECL_INITIAL (x)) < 0)
5763	    error_with_decl (x, "negative width in bit-field `%s'");
5764	  else if (0 < compare_tree_int (DECL_INITIAL (x), max_width))
5765	    pedwarn_with_decl (x, "width of `%s' exceeds its type");
5766	  else if (integer_zerop (DECL_INITIAL (x)) && DECL_NAME (x) != 0)
5767	    error_with_decl (x, "zero width for bit-field `%s'");
5768	  else
5769	    {
5770	      /* The test above has assured us that TREE_INT_CST_HIGH is 0.  */
5771	      unsigned HOST_WIDE_INT width
5772		= tree_low_cst (DECL_INITIAL (x), 1);
5773
5774	      if (TREE_CODE (TREE_TYPE (x)) == ENUMERAL_TYPE
5775		  && (width < min_precision (TYPE_MIN_VALUE (TREE_TYPE (x)),
5776					     TREE_UNSIGNED (TREE_TYPE (x)))
5777		      || (width
5778			  < min_precision (TYPE_MAX_VALUE (TREE_TYPE (x)),
5779					   TREE_UNSIGNED (TREE_TYPE (x))))))
5780		warning_with_decl (x,
5781				   "`%s' is narrower than values of its type");
5782
5783	      DECL_SIZE (x) = bitsize_int (width);
5784	      DECL_BIT_FIELD (x) = 1;
5785	      SET_DECL_C_BIT_FIELD (x);
5786
5787	      if (width == 0
5788		  && ! (* targetm.ms_bitfield_layout_p) (t))
5789		{
5790		  /* field size 0 => force desired amount of alignment.  */
5791#ifdef EMPTY_FIELD_BOUNDARY
5792		  DECL_ALIGN (x) = MAX (DECL_ALIGN (x), EMPTY_FIELD_BOUNDARY);
5793#endif
5794#ifdef PCC_BITFIELD_TYPE_MATTERS
5795		  if (PCC_BITFIELD_TYPE_MATTERS)
5796		    {
5797		      DECL_ALIGN (x) = MAX (DECL_ALIGN (x),
5798					    TYPE_ALIGN (TREE_TYPE (x)));
5799		      DECL_USER_ALIGN (x) |= TYPE_USER_ALIGN (TREE_TYPE (x));
5800		    }
5801#endif
5802		}
5803	    }
5804	}
5805
5806      else if (TREE_TYPE (x) != error_mark_node)
5807	{
5808	  unsigned int min_align = (DECL_PACKED (x) ? BITS_PER_UNIT
5809				    : TYPE_ALIGN (TREE_TYPE (x)));
5810
5811	  /* Non-bit-fields are aligned for their type, except packed
5812	     fields which require only BITS_PER_UNIT alignment.  */
5813	  DECL_ALIGN (x) = MAX (DECL_ALIGN (x), min_align);
5814	  if (! DECL_PACKED (x))
5815	    DECL_USER_ALIGN (x) |= TYPE_USER_ALIGN (TREE_TYPE (x));
5816	}
5817
5818      DECL_INITIAL (x) = 0;
5819
5820      /* Detect flexible array member in an invalid context.  */
5821      if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
5822	  && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
5823	  && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
5824	  && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
5825	{
5826	  if (TREE_CODE (t) == UNION_TYPE)
5827	    error_with_decl (x, "flexible array member in union");
5828	  else if (TREE_CHAIN (x) != NULL_TREE)
5829	    error_with_decl (x, "flexible array member not at end of struct");
5830	  else if (! saw_named_field)
5831	    error_with_decl (x, "flexible array member in otherwise empty struct");
5832	}
5833      if (DECL_NAME (x))
5834	saw_named_field = 1;
5835    }
5836
5837  /* Delete all duplicate fields from the fieldlist */
5838  for (x = fieldlist; x && TREE_CHAIN (x);)
5839    /* Anonymous fields aren't duplicates.  */
5840    if (DECL_NAME (TREE_CHAIN (x)) == 0)
5841      x = TREE_CHAIN (x);
5842    else
5843      {
5844	tree y = fieldlist;
5845
5846	while (1)
5847	  {
5848	    if (DECL_NAME (y) == DECL_NAME (TREE_CHAIN (x)))
5849	      break;
5850	    if (y == x)
5851	      break;
5852	    y = TREE_CHAIN (y);
5853	  }
5854	if (DECL_NAME (y) == DECL_NAME (TREE_CHAIN (x)))
5855	  {
5856	    error_with_decl (TREE_CHAIN (x), "duplicate member `%s'");
5857	    TREE_CHAIN (x) = TREE_CHAIN (TREE_CHAIN (x));
5858	  }
5859	else
5860	  x = TREE_CHAIN (x);
5861      }
5862
5863  /* Now we have the nearly final fieldlist.  Record it,
5864     then lay out the structure or union (including the fields).  */
5865
5866  TYPE_FIELDS (t) = fieldlist;
5867
5868  layout_type (t);
5869
5870  /* Delete all zero-width bit-fields from the fieldlist */
5871  {
5872    tree *fieldlistp = &fieldlist;
5873    while (*fieldlistp)
5874      if (TREE_CODE (*fieldlistp) == FIELD_DECL && DECL_INITIAL (*fieldlistp))
5875	*fieldlistp = TREE_CHAIN (*fieldlistp);
5876      else
5877	fieldlistp = &TREE_CHAIN (*fieldlistp);
5878  }
5879
5880  /* Now we have the truly final field list.
5881     Store it in this type and in the variants.  */
5882
5883  TYPE_FIELDS (t) = fieldlist;
5884
5885  for (x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
5886    {
5887      TYPE_FIELDS (x) = TYPE_FIELDS (t);
5888      TYPE_LANG_SPECIFIC (x) = TYPE_LANG_SPECIFIC (t);
5889      TYPE_ALIGN (x) = TYPE_ALIGN (t);
5890      TYPE_USER_ALIGN (x) = TYPE_USER_ALIGN (t);
5891    }
5892
5893  /* If this was supposed to be a transparent union, but we can't
5894     make it one, warn and turn off the flag.  */
5895  if (TREE_CODE (t) == UNION_TYPE
5896      && TYPE_TRANSPARENT_UNION (t)
5897      && TYPE_MODE (t) != DECL_MODE (TYPE_FIELDS (t)))
5898    {
5899      TYPE_TRANSPARENT_UNION (t) = 0;
5900      warning ("union cannot be made transparent");
5901    }
5902
5903  /* If this structure or union completes the type of any previous
5904     variable declaration, lay it out and output its rtl.  */
5905
5906  if (current_binding_level->n_incomplete != 0)
5907    {
5908      tree decl;
5909      for (decl = current_binding_level->names; decl; decl = TREE_CHAIN (decl))
5910	{
5911	  if (TYPE_MAIN_VARIANT (TREE_TYPE (decl)) == TYPE_MAIN_VARIANT (t)
5912	      && TREE_CODE (decl) != TYPE_DECL)
5913	    {
5914	      layout_decl (decl, 0);
5915	      /* This is a no-op in c-lang.c or something real in objc-actions.c.  */
5916	      maybe_objc_check_decl (decl);
5917	      rest_of_decl_compilation (decl, NULL, toplevel, 0);
5918	      if (! toplevel)
5919		expand_decl (decl);
5920	      if (--current_binding_level->n_incomplete == 0)
5921		break;
5922	    }
5923	  else if (!COMPLETE_TYPE_P (TREE_TYPE (decl))
5924		   && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
5925	    {
5926	      tree element = TREE_TYPE (decl);
5927	      while (TREE_CODE (element) == ARRAY_TYPE)
5928		element = TREE_TYPE (element);
5929	      if (element == t)
5930		{
5931		  layout_array_type (TREE_TYPE (decl));
5932		  if (TREE_CODE (decl) != TYPE_DECL)
5933		    {
5934		      layout_decl (decl, 0);
5935		      maybe_objc_check_decl (decl);
5936		      rest_of_decl_compilation (decl, NULL, toplevel, 0);
5937		      if (! toplevel)
5938			expand_decl (decl);
5939		    }
5940		  if (--current_binding_level->n_incomplete == 0)
5941		    break;
5942		}
5943	    }
5944	}
5945    }
5946
5947  /* Finish debugging output for this type.  */
5948  rest_of_type_compilation (t, toplevel);
5949
5950  return t;
5951}
5952
5953/* Lay out the type T, and its element type, and so on.  */
5954
5955static void
5956layout_array_type (t)
5957     tree t;
5958{
5959  if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
5960    layout_array_type (TREE_TYPE (t));
5961  layout_type (t);
5962}
5963
5964/* Begin compiling the definition of an enumeration type.
5965   NAME is its name (or null if anonymous).
5966   Returns the type object, as yet incomplete.
5967   Also records info about it so that build_enumerator
5968   may be used to declare the individual values as they are read.  */
5969
5970tree
5971start_enum (name)
5972     tree name;
5973{
5974  tree enumtype = 0;
5975
5976  /* If this is the real definition for a previous forward reference,
5977     fill in the contents in the same object that used to be the
5978     forward reference.  */
5979
5980  if (name != 0)
5981    enumtype = lookup_tag (ENUMERAL_TYPE, name, current_binding_level, 1);
5982
5983  if (enumtype == 0 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
5984    {
5985      enumtype = make_node (ENUMERAL_TYPE);
5986      pushtag (name, enumtype);
5987    }
5988
5989  C_TYPE_BEING_DEFINED (enumtype) = 1;
5990
5991  if (TYPE_VALUES (enumtype) != 0)
5992    {
5993      /* This enum is a named one that has been declared already.  */
5994      error ("redeclaration of `enum %s'", IDENTIFIER_POINTER (name));
5995
5996      /* Completely replace its old definition.
5997	 The old enumerators remain defined, however.  */
5998      TYPE_VALUES (enumtype) = 0;
5999    }
6000
6001  enum_next_value = integer_zero_node;
6002  enum_overflow = 0;
6003
6004  if (flag_short_enums)
6005    TYPE_PACKED (enumtype) = 1;
6006
6007  return enumtype;
6008}
6009
6010/* After processing and defining all the values of an enumeration type,
6011   install their decls in the enumeration type and finish it off.
6012   ENUMTYPE is the type object, VALUES a list of decl-value pairs,
6013   and ATTRIBUTES are the specified attributes.
6014   Returns ENUMTYPE.  */
6015
6016tree
6017finish_enum (enumtype, values, attributes)
6018     tree enumtype;
6019     tree values;
6020     tree attributes;
6021{
6022  tree pair, tem;
6023  tree minnode = 0, maxnode = 0, enum_value_type;
6024  int precision, unsign;
6025  int toplevel = (global_binding_level == current_binding_level);
6026
6027  if (in_parm_level_p ())
6028    warning ("enum defined inside parms");
6029
6030  decl_attributes (&enumtype, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
6031
6032  /* Calculate the maximum value of any enumerator in this type.  */
6033
6034  if (values == error_mark_node)
6035    minnode = maxnode = integer_zero_node;
6036  else
6037    {
6038      minnode = maxnode = TREE_VALUE (values);
6039      for (pair = TREE_CHAIN (values); pair; pair = TREE_CHAIN (pair))
6040	{
6041	  tree value = TREE_VALUE (pair);
6042	  if (tree_int_cst_lt (maxnode, value))
6043	    maxnode = value;
6044	  if (tree_int_cst_lt (value, minnode))
6045	    minnode = value;
6046	}
6047    }
6048
6049  /* Construct the final type of this enumeration.  It is the same
6050     as one of the integral types - the narrowest one that fits, except
6051     that normally we only go as narrow as int - and signed iff any of
6052     the values are negative.  */
6053  unsign = (tree_int_cst_sgn (minnode) >= 0);
6054  precision = MAX (min_precision (minnode, unsign),
6055		   min_precision (maxnode, unsign));
6056  if (TYPE_PACKED (enumtype) || precision > TYPE_PRECISION (integer_type_node))
6057    {
6058      tree narrowest = type_for_size (precision, unsign);
6059      if (narrowest == 0)
6060	{
6061	  warning ("enumeration values exceed range of largest integer");
6062	  narrowest = long_long_integer_type_node;
6063	}
6064
6065      precision = TYPE_PRECISION (narrowest);
6066    }
6067  else
6068    precision = TYPE_PRECISION (integer_type_node);
6069
6070  if (precision == TYPE_PRECISION (integer_type_node))
6071    enum_value_type = type_for_size (precision, 0);
6072  else
6073    enum_value_type = enumtype;
6074
6075  TYPE_MIN_VALUE (enumtype) = minnode;
6076  TYPE_MAX_VALUE (enumtype) = maxnode;
6077  TYPE_PRECISION (enumtype) = precision;
6078  TREE_UNSIGNED (enumtype) = unsign;
6079  TYPE_SIZE (enumtype) = 0;
6080  layout_type (enumtype);
6081
6082  if (values != error_mark_node)
6083    {
6084      /* Change the type of the enumerators to be the enum type.  We
6085	 need to do this irrespective of the size of the enum, for
6086	 proper type checking.  Replace the DECL_INITIALs of the
6087	 enumerators, and the value slots of the list, with copies
6088	 that have the enum type; they cannot be modified in place
6089	 because they may be shared (e.g.  integer_zero_node) Finally,
6090	 change the purpose slots to point to the names of the decls.  */
6091      for (pair = values; pair; pair = TREE_CHAIN (pair))
6092	{
6093	  tree enu = TREE_PURPOSE (pair);
6094
6095	  TREE_TYPE (enu) = enumtype;
6096	  DECL_SIZE (enu) = TYPE_SIZE (enumtype);
6097	  DECL_SIZE_UNIT (enu) = TYPE_SIZE_UNIT (enumtype);
6098	  DECL_ALIGN (enu) = TYPE_ALIGN (enumtype);
6099	  DECL_USER_ALIGN (enu) = TYPE_USER_ALIGN (enumtype);
6100	  DECL_MODE (enu) = TYPE_MODE (enumtype);
6101
6102	  /* The ISO C Standard mandates enumerators to have type int,
6103	     even though the underlying type of an enum type is
6104	     unspecified.  Here we convert any enumerators that fit in
6105	     an int to type int, to avoid promotions to unsigned types
6106	     when comparing integers with enumerators that fit in the
6107	     int range.  When -pedantic is given, build_enumerator()
6108	     would have already taken care of those that don't fit.  */
6109	  if (int_fits_type_p (DECL_INITIAL (enu), enum_value_type))
6110	    DECL_INITIAL (enu) = convert (enum_value_type, DECL_INITIAL (enu));
6111	  else
6112	    DECL_INITIAL (enu) = convert (enumtype, DECL_INITIAL (enu));
6113
6114	  TREE_PURPOSE (pair) = DECL_NAME (enu);
6115	  TREE_VALUE (pair) = DECL_INITIAL (enu);
6116	}
6117
6118      TYPE_VALUES (enumtype) = values;
6119    }
6120
6121  /* Fix up all variant types of this enum type.  */
6122  for (tem = TYPE_MAIN_VARIANT (enumtype); tem; tem = TYPE_NEXT_VARIANT (tem))
6123    {
6124      if (tem == enumtype)
6125	continue;
6126      TYPE_VALUES (tem) = TYPE_VALUES (enumtype);
6127      TYPE_MIN_VALUE (tem) = TYPE_MIN_VALUE (enumtype);
6128      TYPE_MAX_VALUE (tem) = TYPE_MAX_VALUE (enumtype);
6129      TYPE_SIZE (tem) = TYPE_SIZE (enumtype);
6130      TYPE_SIZE_UNIT (tem) = TYPE_SIZE_UNIT (enumtype);
6131      TYPE_MODE (tem) = TYPE_MODE (enumtype);
6132      TYPE_PRECISION (tem) = TYPE_PRECISION (enumtype);
6133      TYPE_ALIGN (tem) = TYPE_ALIGN (enumtype);
6134      TYPE_USER_ALIGN (tem) = TYPE_USER_ALIGN (enumtype);
6135      TREE_UNSIGNED (tem) = TREE_UNSIGNED (enumtype);
6136    }
6137
6138  /* Finish debugging output for this type.  */
6139  rest_of_type_compilation (enumtype, toplevel);
6140
6141  return enumtype;
6142}
6143
6144/* Build and install a CONST_DECL for one value of the
6145   current enumeration type (one that was begun with start_enum).
6146   Return a tree-list containing the CONST_DECL and its value.
6147   Assignment of sequential values by default is handled here.  */
6148
6149tree
6150build_enumerator (name, value)
6151     tree name, value;
6152{
6153  tree decl, type;
6154
6155  /* Validate and default VALUE.  */
6156
6157  /* Remove no-op casts from the value.  */
6158  if (value)
6159    STRIP_TYPE_NOPS (value);
6160
6161  if (value != 0)
6162    {
6163      if (TREE_CODE (value) == INTEGER_CST)
6164	{
6165	  value = default_conversion (value);
6166	  constant_expression_warning (value);
6167	}
6168      else
6169	{
6170	  error ("enumerator value for `%s' not integer constant",
6171		 IDENTIFIER_POINTER (name));
6172	  value = 0;
6173	}
6174    }
6175
6176  /* Default based on previous value.  */
6177  /* It should no longer be possible to have NON_LVALUE_EXPR
6178     in the default.  */
6179  if (value == 0)
6180    {
6181      value = enum_next_value;
6182      if (enum_overflow)
6183	error ("overflow in enumeration values");
6184    }
6185
6186  if (pedantic && ! int_fits_type_p (value, integer_type_node))
6187    {
6188      pedwarn ("ISO C restricts enumerator values to range of `int'");
6189      value = convert (integer_type_node, value);
6190    }
6191
6192  /* Set basis for default for next value.  */
6193  enum_next_value = build_binary_op (PLUS_EXPR, value, integer_one_node, 0);
6194  enum_overflow = tree_int_cst_lt (enum_next_value, value);
6195
6196  /* Now create a declaration for the enum value name.  */
6197
6198  type = TREE_TYPE (value);
6199  type = type_for_size (MAX (TYPE_PRECISION (type),
6200			     TYPE_PRECISION (integer_type_node)),
6201			((flag_traditional
6202			  || TYPE_PRECISION (type) >= TYPE_PRECISION (integer_type_node))
6203			 && TREE_UNSIGNED (type)));
6204
6205  decl = build_decl (CONST_DECL, name, type);
6206  DECL_INITIAL (decl) = convert (type, value);
6207  pushdecl (decl);
6208
6209  return tree_cons (decl, value, NULL_TREE);
6210}
6211
6212
6213/* Create the FUNCTION_DECL for a function definition.
6214   DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of
6215   the declaration; they describe the function's name and the type it returns,
6216   but twisted together in a fashion that parallels the syntax of C.
6217
6218   This function creates a binding context for the function body
6219   as well as setting up the FUNCTION_DECL in current_function_decl.
6220
6221   Returns 1 on success.  If the DECLARATOR is not suitable for a function
6222   (it defines a datum instead), we return 0, which tells
6223   yyparse to report a parse error.  */
6224
6225int
6226start_function (declspecs, declarator, attributes)
6227     tree declarator, declspecs, attributes;
6228{
6229  tree decl1, old_decl;
6230  tree restype;
6231  int old_immediate_size_expand = immediate_size_expand;
6232
6233  current_function_returns_value = 0;  /* Assume, until we see it does.  */
6234  current_function_returns_null = 0;
6235  current_function_returns_abnormally = 0;
6236  warn_about_return_type = 0;
6237  current_extern_inline = 0;
6238  c_function_varargs = 0;
6239  named_labels = 0;
6240  shadowed_labels = 0;
6241
6242  /* Don't expand any sizes in the return type of the function.  */
6243  immediate_size_expand = 0;
6244
6245  decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, 1);
6246
6247  /* If the declarator is not suitable for a function definition,
6248     cause a syntax error.  */
6249  if (decl1 == 0)
6250    {
6251      immediate_size_expand = old_immediate_size_expand;
6252      return 0;
6253    }
6254
6255  decl_attributes (&decl1, attributes, 0);
6256
6257  /* If #pragma weak was used, mark the decl weak now.  */
6258  if (current_binding_level == global_binding_level)
6259    maybe_apply_pragma_weak (decl1);
6260
6261  if (DECL_DECLARED_INLINE_P (decl1)
6262      && DECL_UNINLINABLE (decl1)
6263      && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl1)))
6264    warning_with_decl (decl1,
6265		       "inline function `%s' given attribute noinline");
6266
6267  announce_function (decl1);
6268
6269  if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl1))))
6270    {
6271      error ("return type is an incomplete type");
6272      /* Make it return void instead.  */
6273      TREE_TYPE (decl1)
6274	= build_function_type (void_type_node,
6275			       TYPE_ARG_TYPES (TREE_TYPE (decl1)));
6276    }
6277
6278  if (warn_about_return_type)
6279    pedwarn_c99 ("return type defaults to `int'");
6280
6281  /* Save the parm names or decls from this function's declarator
6282     where store_parm_decls will find them.  */
6283  current_function_parms = last_function_parms;
6284  current_function_parm_tags = last_function_parm_tags;
6285
6286  /* Make the init_value nonzero so pushdecl knows this is not tentative.
6287     error_mark_node is replaced below (in poplevel) with the BLOCK.  */
6288  DECL_INITIAL (decl1) = error_mark_node;
6289
6290  /* If this definition isn't a prototype and we had a prototype declaration
6291     before, copy the arg type info from that prototype.
6292     But not if what we had before was a builtin function.  */
6293  old_decl = lookup_name_current_level (DECL_NAME (decl1));
6294  if (old_decl != 0 && TREE_CODE (TREE_TYPE (old_decl)) == FUNCTION_TYPE
6295      && !DECL_BUILT_IN (old_decl)
6296      && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
6297	  == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (old_decl))))
6298      && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0)
6299    {
6300      TREE_TYPE (decl1) = TREE_TYPE (old_decl);
6301      current_function_prototype_file = DECL_SOURCE_FILE (old_decl);
6302      current_function_prototype_line = DECL_SOURCE_LINE (old_decl);
6303    }
6304
6305  /* If there is no explicit declaration, look for any out-of-scope implicit
6306     declarations.  */
6307  if (old_decl == 0)
6308    old_decl = IDENTIFIER_IMPLICIT_DECL (DECL_NAME (decl1));
6309
6310  /* Optionally warn of old-fashioned def with no previous prototype.  */
6311  if (warn_strict_prototypes
6312      && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0
6313      && !(old_decl != 0
6314	   && (TYPE_ARG_TYPES (TREE_TYPE (old_decl)) != 0
6315	       || (DECL_BUILT_IN (old_decl)
6316		   && ! C_DECL_ANTICIPATED (old_decl)))))
6317    warning ("function declaration isn't a prototype");
6318  /* Optionally warn of any global def with no previous prototype.  */
6319  else if (warn_missing_prototypes
6320	   && TREE_PUBLIC (decl1)
6321	   && !(old_decl != 0
6322		&& (TYPE_ARG_TYPES (TREE_TYPE (old_decl)) != 0
6323		    || (DECL_BUILT_IN (old_decl)
6324			&& ! C_DECL_ANTICIPATED (old_decl))))
6325	   && ! MAIN_NAME_P (DECL_NAME (decl1)))
6326    warning_with_decl (decl1, "no previous prototype for `%s'");
6327  /* Optionally warn of any def with no previous prototype
6328     if the function has already been used.  */
6329  else if (warn_missing_prototypes
6330	   && old_decl != 0 && TREE_USED (old_decl)
6331	   && TYPE_ARG_TYPES (TREE_TYPE (old_decl)) == 0)
6332    warning_with_decl (decl1,
6333		       "`%s' was used with no prototype before its definition");
6334  /* Optionally warn of any global def with no previous declaration.  */
6335  else if (warn_missing_declarations
6336	   && TREE_PUBLIC (decl1)
6337	   && old_decl == 0
6338	   && ! MAIN_NAME_P (DECL_NAME (decl1)))
6339    warning_with_decl (decl1, "no previous declaration for `%s'");
6340  /* Optionally warn of any def with no previous declaration
6341     if the function has already been used.  */
6342  else if (warn_missing_declarations
6343	   && old_decl != 0 && TREE_USED (old_decl)
6344	   && old_decl == IDENTIFIER_IMPLICIT_DECL (DECL_NAME (decl1)))
6345    warning_with_decl (decl1,
6346		       "`%s' was used with no declaration before its definition");
6347
6348  /* This is a definition, not a reference.
6349     So normally clear DECL_EXTERNAL.
6350     However, `extern inline' acts like a declaration
6351     except for defining how to inline.  So set DECL_EXTERNAL in that case.  */
6352  DECL_EXTERNAL (decl1) = current_extern_inline;
6353
6354  /* This function exists in static storage.
6355     (This does not mean `static' in the C sense!)  */
6356  TREE_STATIC (decl1) = 1;
6357
6358  /* A nested function is not global.  */
6359  if (current_function_decl != 0)
6360    TREE_PUBLIC (decl1) = 0;
6361
6362  /* Warn for unlikely, improbable, or stupid declarations of `main'.  */
6363  if (warn_main > 0 && MAIN_NAME_P (DECL_NAME (decl1)))
6364    {
6365      tree args;
6366      int argct = 0;
6367
6368      if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
6369	  != integer_type_node)
6370	pedwarn_with_decl (decl1, "return type of `%s' is not `int'");
6371
6372      for (args = TYPE_ARG_TYPES (TREE_TYPE (decl1)); args;
6373	   args = TREE_CHAIN (args))
6374	{
6375	  tree type = args ? TREE_VALUE (args) : 0;
6376
6377	  if (type == void_type_node)
6378	    break;
6379
6380	  ++argct;
6381	  switch (argct)
6382	    {
6383	    case 1:
6384	      if (TYPE_MAIN_VARIANT (type) != integer_type_node)
6385		pedwarn_with_decl (decl1,
6386				   "first argument of `%s' should be `int'");
6387	      break;
6388
6389	    case 2:
6390	      if (TREE_CODE (type) != POINTER_TYPE
6391		  || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
6392		  || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
6393		      != char_type_node))
6394		pedwarn_with_decl (decl1,
6395				   "second argument of `%s' should be `char **'");
6396	      break;
6397
6398	    case 3:
6399	      if (TREE_CODE (type) != POINTER_TYPE
6400		  || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
6401		  || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
6402		      != char_type_node))
6403		pedwarn_with_decl (decl1,
6404				   "third argument of `%s' should probably be `char **'");
6405	      break;
6406	    }
6407	}
6408
6409      /* It is intentional that this message does not mention the third
6410	 argument because it's only mentioned in an appendix of the
6411	 standard.  */
6412      if (argct > 0 && (argct < 2 || argct > 3))
6413	pedwarn_with_decl (decl1, "`%s' takes only zero or two arguments");
6414
6415      if (! TREE_PUBLIC (decl1))
6416	pedwarn_with_decl (decl1, "`%s' is normally a non-static function");
6417    }
6418
6419  /* Record the decl so that the function name is defined.
6420     If we already have a decl for this name, and it is a FUNCTION_DECL,
6421     use the old decl.  */
6422
6423  current_function_decl = pushdecl (decl1);
6424
6425  pushlevel (0);
6426  declare_parm_level (1);
6427  current_binding_level->subblocks_tag_transparent = 1;
6428
6429  make_decl_rtl (current_function_decl, NULL);
6430
6431  restype = TREE_TYPE (TREE_TYPE (current_function_decl));
6432  /* Promote the value to int before returning it.  */
6433  if (c_promoting_integer_type_p (restype))
6434    {
6435      /* It retains unsignedness if traditional
6436	 or if not really getting wider.  */
6437      if (TREE_UNSIGNED (restype)
6438	  && (flag_traditional
6439	      || (TYPE_PRECISION (restype)
6440		  == TYPE_PRECISION (integer_type_node))))
6441	restype = unsigned_type_node;
6442      else
6443	restype = integer_type_node;
6444    }
6445  DECL_RESULT (current_function_decl)
6446    = build_decl (RESULT_DECL, NULL_TREE, restype);
6447
6448  /* If this fcn was already referenced via a block-scope `extern' decl
6449     (or an implicit decl), propagate certain information about the usage.  */
6450  if (TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (current_function_decl)))
6451    TREE_ADDRESSABLE (current_function_decl) = 1;
6452
6453  immediate_size_expand = old_immediate_size_expand;
6454
6455  start_fname_decls ();
6456
6457  return 1;
6458}
6459
6460/* Record that this function is going to be a varargs function.
6461   This is called before store_parm_decls, which is too early
6462   to call mark_varargs directly.  */
6463
6464void
6465c_mark_varargs ()
6466{
6467  c_function_varargs = 1;
6468}
6469
6470/* Store the parameter declarations into the current function declaration.
6471   This is called after parsing the parameter declarations, before
6472   digesting the body of the function.
6473
6474   For an old-style definition, modify the function's type
6475   to specify at least the number of arguments.  */
6476
6477void
6478store_parm_decls ()
6479{
6480  tree fndecl = current_function_decl;
6481  tree parm;
6482
6483  /* This is either a chain of PARM_DECLs (if a prototype was used)
6484     or a list of IDENTIFIER_NODEs (for an old-fashioned C definition).  */
6485  tree specparms = current_function_parms;
6486
6487  /* This is a list of types declared among parms in a prototype.  */
6488  tree parmtags = current_function_parm_tags;
6489
6490  /* This is a chain of PARM_DECLs from old-style parm declarations.  */
6491  tree parmdecls = getdecls ();
6492
6493  /* This is a chain of any other decls that came in among the parm
6494     declarations.  If a parm is declared with  enum {foo, bar} x;
6495     then CONST_DECLs for foo and bar are put here.  */
6496  tree nonparms = 0;
6497
6498  /* The function containing FNDECL, if any.  */
6499  tree context = decl_function_context (fndecl);
6500
6501  /* Nonzero if this definition is written with a prototype.  */
6502  int prototype = 0;
6503
6504  int saved_warn_shadow = warn_shadow;
6505
6506  /* Don't re-emit shadow warnings.  */
6507  warn_shadow = 0;
6508
6509  if (specparms != 0 && TREE_CODE (specparms) != TREE_LIST)
6510    {
6511      /* This case is when the function was defined with an ANSI prototype.
6512	 The parms already have decls, so we need not do anything here
6513	 except record them as in effect
6514	 and complain if any redundant old-style parm decls were written.  */
6515
6516      tree next;
6517      tree others = 0;
6518
6519      prototype = 1;
6520
6521      if (parmdecls != 0)
6522	{
6523	  tree decl, link;
6524
6525	  error_with_decl (fndecl,
6526			   "parm types given both in parmlist and separately");
6527	  /* Get rid of the erroneous decls; don't keep them on
6528	     the list of parms, since they might not be PARM_DECLs.  */
6529	  for (decl = current_binding_level->names;
6530	       decl; decl = TREE_CHAIN (decl))
6531	    if (DECL_NAME (decl))
6532	      IDENTIFIER_LOCAL_VALUE (DECL_NAME (decl)) = 0;
6533	  for (link = current_binding_level->shadowed;
6534	       link; link = TREE_CHAIN (link))
6535	    IDENTIFIER_LOCAL_VALUE (TREE_PURPOSE (link)) = TREE_VALUE (link);
6536	  current_binding_level->names = 0;
6537	  current_binding_level->shadowed = 0;
6538	}
6539
6540      specparms = nreverse (specparms);
6541      for (parm = specparms; parm; parm = next)
6542	{
6543	  next = TREE_CHAIN (parm);
6544	  if (TREE_CODE (parm) == PARM_DECL)
6545	    {
6546	      if (DECL_NAME (parm) == 0)
6547		error_with_decl (parm, "parameter name omitted");
6548	      else if (TREE_CODE (TREE_TYPE (parm)) != ERROR_MARK
6549		       && VOID_TYPE_P (TREE_TYPE (parm)))
6550		{
6551		  error_with_decl (parm, "parameter `%s' declared void");
6552		  /* Change the type to error_mark_node so this parameter
6553		     will be ignored by assign_parms.  */
6554		  TREE_TYPE (parm) = error_mark_node;
6555		}
6556	      pushdecl (parm);
6557	    }
6558	  else
6559	    {
6560	      /* If we find an enum constant or a type tag,
6561		 put it aside for the moment.  */
6562	      TREE_CHAIN (parm) = 0;
6563	      others = chainon (others, parm);
6564	    }
6565	}
6566
6567      /* Get the decls in their original chain order
6568	 and record in the function.  */
6569      DECL_ARGUMENTS (fndecl) = getdecls ();
6570
6571#if 0
6572      /* If this function takes a variable number of arguments,
6573	 add a phony parameter to the end of the parm list,
6574	 to represent the position of the first unnamed argument.  */
6575      if (TREE_VALUE (tree_last (TYPE_ARG_TYPES (TREE_TYPE (fndecl))))
6576	  != void_type_node)
6577	{
6578	  tree dummy = build_decl (PARM_DECL, NULL_TREE, void_type_node);
6579	  /* Let's hope the address of the unnamed parm
6580	     won't depend on its type.  */
6581	  TREE_TYPE (dummy) = integer_type_node;
6582	  DECL_ARG_TYPE (dummy) = integer_type_node;
6583	  DECL_ARGUMENTS (fndecl) = chainon (DECL_ARGUMENTS (fndecl), dummy);
6584	}
6585#endif
6586
6587      /* Now pushdecl the enum constants.  */
6588      for (parm = others; parm; parm = next)
6589	{
6590	  next = TREE_CHAIN (parm);
6591	  if (DECL_NAME (parm) == 0)
6592	    ;
6593	  else if (TYPE_MAIN_VARIANT (TREE_TYPE (parm)) == void_type_node)
6594	    ;
6595	  else if (TREE_CODE (parm) != PARM_DECL)
6596	    pushdecl (parm);
6597	}
6598
6599      storetags (chainon (parmtags, gettags ()));
6600    }
6601  else
6602    {
6603      /* SPECPARMS is an identifier list--a chain of TREE_LIST nodes
6604	 each with a parm name as the TREE_VALUE.
6605
6606	 PARMDECLS is a chain of declarations for parameters.
6607	 Warning! It can also contain CONST_DECLs which are not parameters
6608	 but are names of enumerators of any enum types
6609	 declared among the parameters.
6610
6611	 First match each formal parameter name with its declaration.
6612	 Associate decls with the names and store the decls
6613	 into the TREE_PURPOSE slots.  */
6614
6615      /* We use DECL_WEAK as a flag to show which parameters have been
6616	 seen already since it is not used on PARM_DECL or CONST_DECL.  */
6617      for (parm = parmdecls; parm; parm = TREE_CHAIN (parm))
6618	DECL_WEAK (parm) = 0;
6619
6620      for (parm = specparms; parm; parm = TREE_CHAIN (parm))
6621	{
6622	  tree tail, found = NULL;
6623
6624	  if (TREE_VALUE (parm) == 0)
6625	    {
6626	      error_with_decl (fndecl,
6627			       "parameter name missing from parameter list");
6628	      TREE_PURPOSE (parm) = 0;
6629	      continue;
6630	    }
6631
6632	  /* See if any of the parmdecls specifies this parm by name.
6633	     Ignore any enumerator decls.  */
6634	  for (tail = parmdecls; tail; tail = TREE_CHAIN (tail))
6635	    if (DECL_NAME (tail) == TREE_VALUE (parm)
6636		&& TREE_CODE (tail) == PARM_DECL)
6637	      {
6638		found = tail;
6639		break;
6640	      }
6641
6642	  /* If declaration already marked, we have a duplicate name.
6643	     Complain, and don't use this decl twice.  */
6644	  if (found && DECL_WEAK (found))
6645	    {
6646	      error_with_decl (found, "multiple parameters named `%s'");
6647	      found = 0;
6648	    }
6649
6650	  /* If the declaration says "void", complain and ignore it.  */
6651	  if (found && VOID_TYPE_P (TREE_TYPE (found)))
6652	    {
6653	      error_with_decl (found, "parameter `%s' declared void");
6654	      TREE_TYPE (found) = integer_type_node;
6655	      DECL_ARG_TYPE (found) = integer_type_node;
6656	      layout_decl (found, 0);
6657	    }
6658
6659	  /* Traditionally, a parm declared float is actually a double.  */
6660	  if (found && flag_traditional
6661	      && TYPE_MAIN_VARIANT (TREE_TYPE (found)) == float_type_node)
6662	    {
6663	      TREE_TYPE (found) = double_type_node;
6664	      DECL_ARG_TYPE (found) = double_type_node;
6665	      layout_decl (found, 0);
6666	    }
6667
6668	  /* If no declaration found, default to int.  */
6669	  if (!found)
6670	    {
6671	      found = build_decl (PARM_DECL, TREE_VALUE (parm),
6672				  integer_type_node);
6673	      DECL_ARG_TYPE (found) = TREE_TYPE (found);
6674	      DECL_SOURCE_LINE (found) = DECL_SOURCE_LINE (fndecl);
6675	      DECL_SOURCE_FILE (found) = DECL_SOURCE_FILE (fndecl);
6676	      if (flag_isoc99)
6677		pedwarn_with_decl (found, "type of `%s' defaults to `int'");
6678	      else if (extra_warnings)
6679		warning_with_decl (found, "type of `%s' defaults to `int'");
6680	      pushdecl (found);
6681	    }
6682
6683	  TREE_PURPOSE (parm) = found;
6684
6685	  /* Mark this decl as "already found".  */
6686	  DECL_WEAK (found) = 1;
6687	}
6688
6689      /* Put anything which is on the parmdecls chain and which is
6690	 not a PARM_DECL onto the list NONPARMS.  (The types of
6691	 non-parm things which might appear on the list include
6692	 enumerators and NULL-named TYPE_DECL nodes.) Complain about
6693	 any actual PARM_DECLs not matched with any names.  */
6694
6695      nonparms = 0;
6696      for (parm = parmdecls; parm;)
6697	{
6698	  tree next = TREE_CHAIN (parm);
6699	  TREE_CHAIN (parm) = 0;
6700
6701	  if (TREE_CODE (parm) != PARM_DECL)
6702	    nonparms = chainon (nonparms, parm);
6703	  else
6704	    {
6705	      /* Complain about args with incomplete types.  */
6706	      if (!COMPLETE_TYPE_P (TREE_TYPE (parm)))
6707		{
6708		  error_with_decl (parm, "parameter `%s' has incomplete type");
6709		  TREE_TYPE (parm) = error_mark_node;
6710		}
6711
6712	      if (! DECL_WEAK (parm))
6713		{
6714		  error_with_decl (parm,
6715				   "declaration for parameter `%s' but no such parameter");
6716	          /* Pretend the parameter was not missing.
6717		     This gets us to a standard state and minimizes
6718		     further error messages.  */
6719		  specparms
6720		    = chainon (specparms,
6721			       tree_cons (parm, NULL_TREE, NULL_TREE));
6722		}
6723	    }
6724
6725	  parm = next;
6726	}
6727
6728      /* Chain the declarations together in the order of the list of
6729         names.  Store that chain in the function decl, replacing the
6730         list of names.  */
6731      parm = specparms;
6732      DECL_ARGUMENTS (fndecl) = 0;
6733      {
6734	tree last;
6735	for (last = 0; parm; parm = TREE_CHAIN (parm))
6736	  if (TREE_PURPOSE (parm))
6737	    {
6738	      if (last == 0)
6739		DECL_ARGUMENTS (fndecl) = TREE_PURPOSE (parm);
6740	      else
6741		TREE_CHAIN (last) = TREE_PURPOSE (parm);
6742	      last = TREE_PURPOSE (parm);
6743	      TREE_CHAIN (last) = 0;
6744	    }
6745      }
6746
6747      /* If there was a previous prototype,
6748	 set the DECL_ARG_TYPE of each argument according to
6749	 the type previously specified, and report any mismatches.  */
6750
6751      if (TYPE_ARG_TYPES (TREE_TYPE (fndecl)))
6752	{
6753	  tree type;
6754	  for (parm = DECL_ARGUMENTS (fndecl),
6755	       type = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
6756	       parm || (type && (TYPE_MAIN_VARIANT (TREE_VALUE (type))
6757				 != void_type_node));
6758	       parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
6759	    {
6760	      if (parm == 0 || type == 0
6761		  || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
6762		{
6763		  error ("number of arguments doesn't match prototype");
6764		  error_with_file_and_line (current_function_prototype_file,
6765					    current_function_prototype_line,
6766					    "prototype declaration");
6767		  break;
6768		}
6769	      /* Type for passing arg must be consistent with that
6770		 declared for the arg.  ISO C says we take the unqualified
6771		 type for parameters declared with qualified type.  */
6772	      if (! comptypes (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (parm)),
6773			       TYPE_MAIN_VARIANT (TREE_VALUE (type))))
6774		{
6775		  if (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
6776		      == TYPE_MAIN_VARIANT (TREE_VALUE (type)))
6777		    {
6778		      /* Adjust argument to match prototype.  E.g. a previous
6779			 `int foo(float);' prototype causes
6780			 `int foo(x) float x; {...}' to be treated like
6781			 `int foo(float x) {...}'.  This is particularly
6782			 useful for argument types like uid_t.  */
6783		      DECL_ARG_TYPE (parm) = TREE_TYPE (parm);
6784
6785		      if (PROMOTE_PROTOTYPES
6786			  && INTEGRAL_TYPE_P (TREE_TYPE (parm))
6787			  && TYPE_PRECISION (TREE_TYPE (parm))
6788			  < TYPE_PRECISION (integer_type_node))
6789			DECL_ARG_TYPE (parm) = integer_type_node;
6790
6791		      if (pedantic)
6792			{
6793			  pedwarn ("promoted argument `%s' doesn't match prototype",
6794				   IDENTIFIER_POINTER (DECL_NAME (parm)));
6795			  warning_with_file_and_line
6796			    (current_function_prototype_file,
6797			     current_function_prototype_line,
6798			     "prototype declaration");
6799			}
6800		    }
6801		  /* If -traditional, allow `int' argument to match
6802		     `unsigned' prototype.  */
6803		  else if (! (flag_traditional
6804			      && TYPE_MAIN_VARIANT (TREE_TYPE (parm)) == integer_type_node
6805			      && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == unsigned_type_node))
6806		    {
6807		      error ("argument `%s' doesn't match prototype",
6808			     IDENTIFIER_POINTER (DECL_NAME (parm)));
6809		      error_with_file_and_line (current_function_prototype_file,
6810						current_function_prototype_line,
6811						"prototype declaration");
6812		    }
6813		}
6814	    }
6815	  TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = 0;
6816	}
6817
6818      /* Otherwise, create a prototype that would match.  */
6819
6820      else
6821	{
6822	  tree actual = 0, last = 0, type;
6823
6824	  for (parm = DECL_ARGUMENTS (fndecl); parm; parm = TREE_CHAIN (parm))
6825	    {
6826	      type = tree_cons (NULL_TREE, DECL_ARG_TYPE (parm), NULL_TREE);
6827	      if (last)
6828		TREE_CHAIN (last) = type;
6829	      else
6830		actual = type;
6831	      last = type;
6832	    }
6833	  type = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
6834	  if (last)
6835	    TREE_CHAIN (last) = type;
6836	  else
6837	    actual = type;
6838
6839	  /* We are going to assign a new value for the TYPE_ACTUAL_ARG_TYPES
6840	     of the type of this function, but we need to avoid having this
6841	     affect the types of other similarly-typed functions, so we must
6842	     first force the generation of an identical (but separate) type
6843	     node for the relevant function type.  The new node we create
6844	     will be a variant of the main variant of the original function
6845	     type.  */
6846
6847	  TREE_TYPE (fndecl) = build_type_copy (TREE_TYPE (fndecl));
6848
6849	  TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = actual;
6850	}
6851
6852      /* Now store the final chain of decls for the arguments
6853	 as the decl-chain of the current lexical scope.
6854	 Put the enumerators in as well, at the front so that
6855	 DECL_ARGUMENTS is not modified.  */
6856
6857      storedecls (chainon (nonparms, DECL_ARGUMENTS (fndecl)));
6858    }
6859
6860  /* Make sure the binding level for the top of the function body
6861     gets a BLOCK if there are any in the function.
6862     Otherwise, the dbx output is wrong.  */
6863
6864  keep_next_if_subblocks = 1;
6865
6866  /* ??? This might be an improvement,
6867     but needs to be thought about some more.  */
6868#if 0
6869  keep_next_level_flag = 1;
6870#endif
6871
6872  /* Write a record describing this function definition to the prototypes
6873     file (if requested).  */
6874
6875  gen_aux_info_record (fndecl, 1, 0, prototype);
6876
6877  /* Initialize the RTL code for the function.  */
6878  init_function_start (fndecl, input_filename, lineno);
6879
6880  /* Begin the statement tree for this function.  */
6881  begin_stmt_tree (&DECL_SAVED_TREE (current_function_decl));
6882
6883  /* If this is a nested function, save away the sizes of any
6884     variable-size types so that we can expand them when generating
6885     RTL.  */
6886  if (context)
6887    {
6888      tree t;
6889
6890      DECL_LANG_SPECIFIC (fndecl)->pending_sizes
6891	= nreverse (get_pending_sizes ());
6892      for (t = DECL_LANG_SPECIFIC (fndecl)->pending_sizes;
6893	   t;
6894	   t = TREE_CHAIN (t))
6895	SAVE_EXPR_CONTEXT (TREE_VALUE (t)) = context;
6896    }
6897
6898  /* This function is being processed in whole-function mode.  */
6899  cfun->x_whole_function_mode_p = 1;
6900
6901  /* Even though we're inside a function body, we still don't want to
6902     call expand_expr to calculate the size of a variable-sized array.
6903     We haven't necessarily assigned RTL to all variables yet, so it's
6904     not safe to try to expand expressions involving them.  */
6905  immediate_size_expand = 0;
6906  cfun->x_dont_save_pending_sizes_p = 1;
6907
6908  warn_shadow = saved_warn_shadow;
6909}
6910
6911/* Finish up a function declaration and compile that function
6912   all the way to assembler language output.  The free the storage
6913   for the function definition.
6914
6915   This is called after parsing the body of the function definition.
6916
6917   NESTED is nonzero if the function being finished is nested in another.
6918   CAN_DEFER_P is nonzero if the function may be deferred.  */
6919
6920void
6921finish_function (nested, can_defer_p)
6922     int nested;
6923     int can_defer_p;
6924{
6925  tree fndecl = current_function_decl;
6926
6927#if 0
6928  /* This caused &foo to be of type ptr-to-const-function which then
6929     got a warning when stored in a ptr-to-function variable.  */
6930  TREE_READONLY (fndecl) = 1;
6931#endif
6932
6933  poplevel (1, 0, 1);
6934  BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
6935
6936  /* Must mark the RESULT_DECL as being in this function.  */
6937
6938  DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
6939
6940  /* Obey `register' declarations if `setjmp' is called in this fn.  */
6941  if (flag_traditional && current_function_calls_setjmp)
6942    {
6943      setjmp_protect (DECL_INITIAL (fndecl));
6944      setjmp_protect_args ();
6945    }
6946
6947  if (MAIN_NAME_P (DECL_NAME (fndecl)) && flag_hosted)
6948    {
6949      if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (fndecl)))
6950	  != integer_type_node)
6951	{
6952	  /* If warn_main is 1 (-Wmain) or 2 (-Wall), we have already warned.
6953	     If warn_main is -1 (-Wno-main) we don't want to be warned.  */
6954	  if (! warn_main)
6955	    pedwarn_with_decl (fndecl, "return type of `%s' is not `int'");
6956	}
6957      else
6958	{
6959#ifdef DEFAULT_MAIN_RETURN
6960	  /* Make it so that `main' always returns success by default.  */
6961	  DEFAULT_MAIN_RETURN;
6962#else
6963	  if (flag_isoc99)
6964	    c_expand_return (integer_zero_node);
6965#endif
6966	}
6967    }
6968
6969  finish_fname_decls ();
6970
6971  /* Tie off the statement tree for this function.  */
6972  finish_stmt_tree (&DECL_SAVED_TREE (fndecl));
6973
6974  /* Complain if there's just no return statement.  */
6975  if (warn_return_type
6976      && TREE_CODE (TREE_TYPE (TREE_TYPE (fndecl))) != VOID_TYPE
6977      && !current_function_returns_value && !current_function_returns_null
6978      /* Don't complain if we abort.  */
6979      && !current_function_returns_abnormally
6980      /* Don't warn for main().  */
6981      && !MAIN_NAME_P (DECL_NAME (fndecl))
6982      /* Or if they didn't actually specify a return type.  */
6983      && !C_FUNCTION_IMPLICIT_INT (fndecl)
6984      /* Normally, with -Wreturn-type, flow will complain.  Unless we're an
6985	 inline function, as we might never be compiled separately.  */
6986      && DECL_INLINE (fndecl))
6987    warning ("no return statement in function returning non-void");
6988
6989  /* Clear out memory we no longer need.  */
6990  free_after_parsing (cfun);
6991  /* Since we never call rest_of_compilation, we never clear
6992     CFUN.  Do so explicitly.  */
6993  free_after_compilation (cfun);
6994  cfun = NULL;
6995
6996  if (! nested)
6997    {
6998      /* Generate RTL for the body of this function.  */
6999      c_expand_body (fndecl, nested, can_defer_p);
7000
7001      /* Let the error reporting routines know that we're outside a
7002	 function.  For a nested function, this value is used in
7003	 pop_c_function_context and then reset via pop_function_context.  */
7004      current_function_decl = NULL;
7005    }
7006}
7007
7008/* Generate the RTL for a deferred function FNDECL.  */
7009
7010void
7011c_expand_deferred_function (fndecl)
7012     tree fndecl;
7013{
7014  /* DECL_INLINE or DECL_RESULT might got cleared after the inline
7015     function was deferred, e.g. in duplicate_decls.  */
7016  if (DECL_INLINE (fndecl) && DECL_RESULT (fndecl))
7017    {
7018      c_expand_body (fndecl, 0, 0);
7019      current_function_decl = NULL;
7020    }
7021}
7022
7023/* Generate the RTL for the body of FNDECL.  If NESTED_P is non-zero,
7024   then we are already in the process of generating RTL for another
7025   function.  If can_defer_p is zero, we won't attempt to defer the
7026   generation of RTL.  */
7027
7028static void
7029c_expand_body (fndecl, nested_p, can_defer_p)
7030     tree fndecl;
7031     int nested_p, can_defer_p;
7032{
7033  int uninlinable = 1;
7034
7035  /* There's no reason to do any of the work here if we're only doing
7036     semantic analysis; this code just generates RTL.  */
7037  if (flag_syntax_only)
7038    return;
7039
7040  if (flag_inline_trees)
7041    {
7042      /* First, cache whether the current function is inlinable.  Some
7043         predicates depend on cfun and current_function_decl to
7044         function completely.  */
7045      timevar_push (TV_INTEGRATION);
7046      uninlinable = ! tree_inlinable_function_p (fndecl);
7047
7048      if (! uninlinable && can_defer_p
7049	  /* Save function tree for inlining.  Should return 0 if the
7050             language does not support function deferring or the
7051             function could not be deferred.  */
7052	  && defer_fn (fndecl))
7053	{
7054	  /* Let the back-end know that this function exists.  */
7055	  (*debug_hooks->deferred_inline_function) (fndecl);
7056          timevar_pop (TV_INTEGRATION);
7057	  return;
7058	}
7059
7060      /* Then, inline any functions called in it.  */
7061      optimize_inline_calls (fndecl);
7062      timevar_pop (TV_INTEGRATION);
7063    }
7064
7065  timevar_push (TV_EXPAND);
7066
7067  if (nested_p)
7068    {
7069      /* Make sure that we will evaluate variable-sized types involved
7070	 in our function's type.  */
7071      expand_pending_sizes (DECL_LANG_SPECIFIC (fndecl)->pending_sizes);
7072      /* Squirrel away our current state.  */
7073      push_function_context ();
7074    }
7075
7076  /* Initialize the RTL code for the function.  */
7077  current_function_decl = fndecl;
7078  input_filename = DECL_SOURCE_FILE (fndecl);
7079  init_function_start (fndecl, input_filename, DECL_SOURCE_LINE (fndecl));
7080
7081  /* This function is being processed in whole-function mode.  */
7082  cfun->x_whole_function_mode_p = 1;
7083
7084  /* Even though we're inside a function body, we still don't want to
7085     call expand_expr to calculate the size of a variable-sized array.
7086     We haven't necessarily assigned RTL to all variables yet, so it's
7087     not safe to try to expand expressions involving them.  */
7088  immediate_size_expand = 0;
7089  cfun->x_dont_save_pending_sizes_p = 1;
7090
7091  /* If this is a varargs function, inform function.c.  */
7092  if (c_function_varargs)
7093    mark_varargs ();
7094
7095  /* Set up parameters and prepare for return, for the function.  */
7096  expand_function_start (fndecl, 0);
7097
7098  /* If this function is `main', emit a call to `__main'
7099     to run global initializers, etc.  */
7100  if (DECL_NAME (fndecl)
7101      && MAIN_NAME_P (DECL_NAME (fndecl))
7102      && DECL_CONTEXT (fndecl) == NULL_TREE)
7103    expand_main_function ();
7104
7105  /* Generate the RTL for this function.  */
7106  expand_stmt (DECL_SAVED_TREE (fndecl));
7107  if (uninlinable)
7108    {
7109      /* Allow the body of the function to be garbage collected.  */
7110      DECL_SAVED_TREE (fndecl) = NULL_TREE;
7111    }
7112
7113  /* We hard-wired immediate_size_expand to zero above.
7114     expand_function_end will decrement this variable.  So, we set the
7115     variable to one here, so that after the decrement it will remain
7116     zero.  */
7117  immediate_size_expand = 1;
7118
7119  /* Allow language dialects to perform special processing.  */
7120  if (lang_expand_function_end)
7121    (*lang_expand_function_end) ();
7122
7123  /* Generate rtl for function exit.  */
7124  expand_function_end (input_filename, lineno, 0);
7125
7126  /* If this is a nested function, protect the local variables in the stack
7127     above us from being collected while we're compiling this function.  */
7128  if (nested_p)
7129    ggc_push_context ();
7130
7131  /* Run the optimizers and output the assembler code for this function.  */
7132  rest_of_compilation (fndecl);
7133
7134  /* Undo the GC context switch.  */
7135  if (nested_p)
7136    ggc_pop_context ();
7137
7138  /* With just -W, complain only if function returns both with
7139     and without a value.  */
7140  if (extra_warnings
7141      && current_function_returns_value
7142      && current_function_returns_null)
7143    warning ("this function may return with or without a value");
7144
7145  /* If requested, warn about function definitions where the function will
7146     return a value (usually of some struct or union type) which itself will
7147     take up a lot of stack space.  */
7148
7149  if (warn_larger_than && !DECL_EXTERNAL (fndecl) && TREE_TYPE (fndecl))
7150    {
7151      tree ret_type = TREE_TYPE (TREE_TYPE (fndecl));
7152
7153      if (ret_type && TYPE_SIZE_UNIT (ret_type)
7154	  && TREE_CODE (TYPE_SIZE_UNIT (ret_type)) == INTEGER_CST
7155	  && 0 < compare_tree_int (TYPE_SIZE_UNIT (ret_type),
7156				   larger_than_size))
7157	{
7158	  unsigned int size_as_int
7159	    = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (ret_type));
7160
7161	  if (compare_tree_int (TYPE_SIZE_UNIT (ret_type), size_as_int) == 0)
7162	    warning_with_decl (fndecl,
7163			       "size of return value of `%s' is %u bytes",
7164			       size_as_int);
7165	  else
7166	    warning_with_decl (fndecl,
7167			       "size of return value of `%s' is larger than %d bytes",
7168			       larger_than_size);
7169	}
7170    }
7171
7172  if (DECL_SAVED_INSNS (fndecl) == 0 && ! nested_p
7173      && ! flag_inline_trees)
7174    {
7175      /* Stop pointing to the local nodes about to be freed.
7176	 But DECL_INITIAL must remain nonzero so we know this
7177	 was an actual function definition.
7178	 For a nested function, this is done in pop_c_function_context.
7179	 If rest_of_compilation set this to 0, leave it 0.  */
7180      if (DECL_INITIAL (fndecl) != 0)
7181	DECL_INITIAL (fndecl) = error_mark_node;
7182
7183      DECL_ARGUMENTS (fndecl) = 0;
7184    }
7185
7186  if (DECL_STATIC_CONSTRUCTOR (fndecl))
7187    {
7188      if (targetm.have_ctors_dtors)
7189	(* targetm.asm_out.constructor) (XEXP (DECL_RTL (fndecl), 0),
7190				         DEFAULT_INIT_PRIORITY);
7191      else
7192	static_ctors = tree_cons (NULL_TREE, fndecl, static_ctors);
7193    }
7194
7195  if (DECL_STATIC_DESTRUCTOR (fndecl))
7196    {
7197      if (targetm.have_ctors_dtors)
7198	(* targetm.asm_out.destructor) (XEXP (DECL_RTL (fndecl), 0),
7199				        DEFAULT_INIT_PRIORITY);
7200      else
7201	static_dtors = tree_cons (NULL_TREE, fndecl, static_dtors);
7202    }
7203
7204  if (nested_p)
7205    /* Return to the enclosing function.  */
7206    pop_function_context ();
7207  timevar_pop (TV_EXPAND);
7208}
7209
7210/* Check the declarations given in a for-loop for satisfying the C99
7211   constraints.  */
7212void
7213check_for_loop_decls ()
7214{
7215  tree t;
7216
7217  if (!flag_isoc99)
7218    {
7219      /* If we get here, declarations have been used in a for loop without
7220	 the C99 for loop scope.  This doesn't make much sense, so don't
7221	 allow it.  */
7222      error ("`for' loop initial declaration used outside C99 mode");
7223      return;
7224    }
7225  /* C99 subclause 6.8.5 paragraph 3:
7226
7227       [#3]  The  declaration  part  of  a for statement shall only
7228       declare identifiers for objects having storage class auto or
7229       register.
7230
7231     It isn't clear whether, in this sentence, "identifiers" binds to
7232     "shall only declare" or to "objects" - that is, whether all identifiers
7233     declared must be identifiers for objects, or whether the restriction
7234     only applies to those that are.  (A question on this in comp.std.c
7235     in November 2000 received no answer.)  We implement the strictest
7236     interpretation, to avoid creating an extension which later causes
7237     problems.  */
7238
7239  for (t = gettags (); t; t = TREE_CHAIN (t))
7240    {
7241      if (TREE_PURPOSE (t) != 0)
7242        {
7243          enum tree_code code = TREE_CODE (TREE_VALUE (t));
7244
7245          if (code == RECORD_TYPE)
7246            error ("`struct %s' declared in `for' loop initial declaration",
7247                   IDENTIFIER_POINTER (TREE_PURPOSE (t)));
7248          else if (code == UNION_TYPE)
7249            error ("`union %s' declared in `for' loop initial declaration",
7250                   IDENTIFIER_POINTER (TREE_PURPOSE (t)));
7251          else
7252            error ("`enum %s' declared in `for' loop initial declaration",
7253                   IDENTIFIER_POINTER (TREE_PURPOSE (t)));
7254        }
7255    }
7256
7257  for (t = getdecls (); t; t = TREE_CHAIN (t))
7258    {
7259      if (TREE_CODE (t) != VAR_DECL && DECL_NAME (t))
7260	error_with_decl (t, "declaration of non-variable `%s' in `for' loop initial declaration");
7261      else if (TREE_STATIC (t))
7262	error_with_decl (t, "declaration of static variable `%s' in `for' loop initial declaration");
7263      else if (DECL_EXTERNAL (t))
7264	error_with_decl (t, "declaration of `extern' variable `%s' in `for' loop initial declaration");
7265    }
7266}
7267
7268/* Save and restore the variables in this file and elsewhere
7269   that keep track of the progress of compilation of the current function.
7270   Used for nested functions.  */
7271
7272struct c_language_function
7273{
7274  struct language_function base;
7275  tree named_labels;
7276  tree shadowed_labels;
7277  int returns_value;
7278  int returns_null;
7279  int returns_abnormally;
7280  int warn_about_return_type;
7281  int extern_inline;
7282  struct binding_level *binding_level;
7283};
7284
7285/* Save and reinitialize the variables
7286   used during compilation of a C function.  */
7287
7288void
7289push_c_function_context (f)
7290     struct function *f;
7291{
7292  struct c_language_function *p;
7293  p = ((struct c_language_function *)
7294       xmalloc (sizeof (struct c_language_function)));
7295  f->language = (struct language_function *) p;
7296
7297  p->base.x_stmt_tree = c_stmt_tree;
7298  p->base.x_scope_stmt_stack = c_scope_stmt_stack;
7299  p->named_labels = named_labels;
7300  p->shadowed_labels = shadowed_labels;
7301  p->returns_value = current_function_returns_value;
7302  p->returns_null = current_function_returns_null;
7303  p->returns_abnormally = current_function_returns_abnormally;
7304  p->warn_about_return_type = warn_about_return_type;
7305  p->extern_inline = current_extern_inline;
7306  p->binding_level = current_binding_level;
7307}
7308
7309/* Restore the variables used during compilation of a C function.  */
7310
7311void
7312pop_c_function_context (f)
7313     struct function *f;
7314{
7315  struct c_language_function *p
7316    = (struct c_language_function *) f->language;
7317  tree link;
7318
7319  /* Bring back all the labels that were shadowed.  */
7320  for (link = shadowed_labels; link; link = TREE_CHAIN (link))
7321    if (DECL_NAME (TREE_VALUE (link)) != 0)
7322      IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link)))
7323	= TREE_VALUE (link);
7324
7325  if (DECL_SAVED_INSNS (current_function_decl) == 0
7326      && DECL_SAVED_TREE (current_function_decl) == NULL_TREE)
7327    {
7328      /* Stop pointing to the local nodes about to be freed.  */
7329      /* But DECL_INITIAL must remain nonzero so we know this
7330	 was an actual function definition.  */
7331      DECL_INITIAL (current_function_decl) = error_mark_node;
7332      DECL_ARGUMENTS (current_function_decl) = 0;
7333    }
7334
7335  c_stmt_tree = p->base.x_stmt_tree;
7336  c_scope_stmt_stack = p->base.x_scope_stmt_stack;
7337  named_labels = p->named_labels;
7338  shadowed_labels = p->shadowed_labels;
7339  current_function_returns_value = p->returns_value;
7340  current_function_returns_null = p->returns_null;
7341  current_function_returns_abnormally = p->returns_abnormally;
7342  warn_about_return_type = p->warn_about_return_type;
7343  current_extern_inline = p->extern_inline;
7344  current_binding_level = p->binding_level;
7345
7346  free (p);
7347  f->language = 0;
7348}
7349
7350/* Mark the language specific parts of F for GC.  */
7351
7352void
7353mark_c_function_context (f)
7354     struct function *f;
7355{
7356  struct c_language_function *p
7357    = (struct c_language_function *) f->language;
7358
7359  if (p == 0)
7360    return;
7361
7362  mark_c_language_function (&p->base);
7363  ggc_mark_tree (p->shadowed_labels);
7364  ggc_mark_tree (p->named_labels);
7365  mark_binding_level (&p->binding_level);
7366}
7367
7368/* Copy the DECL_LANG_SPECIFIC data associated with NODE.  */
7369
7370void
7371copy_lang_decl (decl)
7372     tree decl;
7373{
7374  struct lang_decl *ld;
7375
7376  if (!DECL_LANG_SPECIFIC (decl))
7377    return;
7378
7379  ld = (struct lang_decl *) ggc_alloc (sizeof (struct lang_decl));
7380  memcpy ((char *) ld, (char *) DECL_LANG_SPECIFIC (decl),
7381	  sizeof (struct lang_decl));
7382  DECL_LANG_SPECIFIC (decl) = ld;
7383}
7384
7385/* Mark the language specific bits in T for GC.  */
7386
7387void
7388lang_mark_tree (t)
7389     tree t;
7390{
7391  if (TREE_CODE (t) == IDENTIFIER_NODE)
7392    {
7393      struct lang_identifier *i = (struct lang_identifier *) t;
7394      ggc_mark_tree (i->global_value);
7395      ggc_mark_tree (i->local_value);
7396      ggc_mark_tree (i->label_value);
7397      ggc_mark_tree (i->implicit_decl);
7398      ggc_mark_tree (i->error_locus);
7399      ggc_mark_tree (i->limbo_value);
7400    }
7401  else if (TYPE_P (t) && TYPE_LANG_SPECIFIC (t))
7402    ggc_mark (TYPE_LANG_SPECIFIC (t));
7403  else if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
7404    {
7405      ggc_mark (DECL_LANG_SPECIFIC (t));
7406      c_mark_lang_decl (&DECL_LANG_SPECIFIC (t)->base);
7407      ggc_mark_tree (DECL_LANG_SPECIFIC (t)->pending_sizes);
7408    }
7409}
7410
7411/* The functions below are required for functionality of doing
7412   function at once processing in the C front end. Currently these
7413   functions are not called from anywhere in the C front end, but as
7414   these changes continue, that will change.  */
7415
7416/* Returns non-zero if the current statement is a full expression,
7417   i.e. temporaries created during that statement should be destroyed
7418   at the end of the statement.  */
7419
7420int
7421stmts_are_full_exprs_p ()
7422{
7423  return 0;
7424}
7425
7426/* Returns the stmt_tree (if any) to which statements are currently
7427   being added.  If there is no active statement-tree, NULL is
7428   returned.  */
7429
7430stmt_tree
7431current_stmt_tree ()
7432{
7433  return &c_stmt_tree;
7434}
7435
7436/* Returns the stack of SCOPE_STMTs for the current function.  */
7437
7438tree *
7439current_scope_stmt_stack ()
7440{
7441  return &c_scope_stmt_stack;
7442}
7443
7444/* Nonzero if TYPE is an anonymous union or struct type.  Always 0 in
7445   C.  */
7446
7447int
7448anon_aggr_type_p (node)
7449     tree node ATTRIBUTE_UNUSED;
7450{
7451  return 0;
7452}
7453
7454/* Dummy function in place of callback used by C++.  */
7455
7456void
7457extract_interface_info ()
7458{
7459}
7460
7461/* Return a new COMPOUND_STMT, after adding it to the current
7462   statement tree.  */
7463
7464tree
7465c_begin_compound_stmt ()
7466{
7467  tree stmt;
7468
7469  /* Create the COMPOUND_STMT.  */
7470  stmt = add_stmt (build_stmt (COMPOUND_STMT, NULL_TREE));
7471
7472  return stmt;
7473}
7474
7475/* Expand T (a DECL_STMT) if it declares an entity not handled by the
7476   common code.  */
7477
7478void
7479c_expand_decl_stmt (t)
7480     tree t;
7481{
7482  tree decl = DECL_STMT_DECL (t);
7483
7484  /* Expand nested functions.  */
7485  if (TREE_CODE (decl) == FUNCTION_DECL
7486      && DECL_CONTEXT (decl) == current_function_decl
7487      && DECL_SAVED_TREE (decl))
7488    c_expand_body (decl, /*nested_p=*/1, /*can_defer_p=*/0);
7489}
7490
7491/* Return the IDENTIFIER_GLOBAL_VALUE of T, for use in common code, since
7492   the definition of IDENTIFIER_GLOBAL_VALUE is different for C and C++.  */
7493
7494tree
7495identifier_global_value	(t)
7496     tree t;
7497{
7498  return IDENTIFIER_GLOBAL_VALUE (t);
7499}
7500
7501/* Record a builtin type for C.  If NAME is non-NULL, it is the name used;
7502   otherwise the name is found in ridpointers from RID_INDEX.  */
7503
7504void
7505record_builtin_type (rid_index, name, type)
7506     enum rid rid_index;
7507     const char *name;
7508     tree type;
7509{
7510  tree id;
7511  if (name == 0)
7512    id = ridpointers[(int) rid_index];
7513  else
7514    id = get_identifier (name);
7515  pushdecl (build_decl (TYPE_DECL, id, type));
7516}
7517
7518/* Build the void_list_node (void_type_node having been created).  */
7519tree
7520build_void_list_node ()
7521{
7522  tree t = build_tree_list (NULL_TREE, void_type_node);
7523  return t;
7524}
7525