cppinit.c (COMMAND_LINE_OPTIONS): Give all relevant -W options their own entries.
[gcc.git] / gcc / c-decl.c
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
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
11
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
21
22 /* Process declarations and symbol lookup for C front end.
23 Also constructs types; the standard scalar types at initialization,
24 and structure, union, array and enum types when they are declared. */
25
26 /* ??? not all decl nodes are given the most useful possible
27 line numbers. For example, the CONST_DECLs for enum values. */
28
29 #include "config.h"
30 #include "system.h"
31 #include "intl.h"
32 #include "tree.h"
33 #include "tree-inline.h"
34 #include "rtl.h"
35 #include "flags.h"
36 #include "function.h"
37 #include "output.h"
38 #include "expr.h"
39 #include "c-tree.h"
40 #include "toplev.h"
41 #include "ggc.h"
42 #include "tm_p.h"
43 #include "cpplib.h"
44 #include "target.h"
45 #include "debug.h"
46 #include "timevar.h"
47 #include "c-common.h"
48 #include "c-pragma.h"
49
50 /* In grokdeclarator, distinguish syntactic contexts of declarators. */
51 enum decl_context
52 { NORMAL, /* Ordinary declaration */
53 FUNCDEF, /* Function definition */
54 PARM, /* Declaration of parm before function body */
55 FIELD, /* Declaration inside struct or union */
56 BITFIELD, /* Likewise but with specified width */
57 TYPENAME}; /* Typename (inside cast or sizeof) */
58
59 \f
60 /* Nonzero if we have seen an invalid cross reference
61 to a struct, union, or enum, but not yet printed the message. */
62
63 tree pending_invalid_xref;
64 /* File and line to appear in the eventual error message. */
65 const char *pending_invalid_xref_file;
66 int pending_invalid_xref_line;
67
68 /* While defining an enum type, this is 1 plus the last enumerator
69 constant value. Note that will do not have to save this or `enum_overflow'
70 around nested function definition since such a definition could only
71 occur in an enum value expression and we don't use these variables in
72 that case. */
73
74 static tree enum_next_value;
75
76 /* Nonzero means that there was overflow computing enum_next_value. */
77
78 static int enum_overflow;
79
80 /* Parsing a function declarator leaves a list of parameter names
81 or a chain or parameter decls here. */
82
83 static tree last_function_parms;
84
85 /* Parsing a function declarator leaves here a chain of structure
86 and enum types declared in the parmlist. */
87
88 static tree last_function_parm_tags;
89
90 /* After parsing the declarator that starts a function definition,
91 `start_function' puts here the list of parameter names or chain of decls.
92 `store_parm_decls' finds it here. */
93
94 static tree current_function_parms;
95
96 /* Similar, for last_function_parm_tags. */
97 static tree current_function_parm_tags;
98
99 /* Similar, for the file and line that the prototype came from if this is
100 an old-style definition. */
101 static const char *current_function_prototype_file;
102 static int current_function_prototype_line;
103
104 /* The current statement tree. */
105
106 static GTY(()) struct stmt_tree_s c_stmt_tree;
107
108 /* The current scope statement stack. */
109
110 static GTY(()) tree c_scope_stmt_stack;
111
112 /* A list (chain of TREE_LIST nodes) of all LABEL_DECLs in the function
113 that have names. Here so we can clear out their names' definitions
114 at the end of the function. */
115
116 static GTY(()) tree named_labels;
117
118 /* A list of LABEL_DECLs from outer contexts that are currently shadowed. */
119
120 static GTY(()) tree shadowed_labels;
121
122 /* Nonzero when store_parm_decls is called indicates a varargs function.
123 Value not meaningful after store_parm_decls. */
124
125 static int c_function_varargs;
126
127 /* Set to 0 at beginning of a function definition, set to 1 if
128 a return statement that specifies a return value is seen. */
129
130 int current_function_returns_value;
131
132 /* Set to 0 at beginning of a function definition, set to 1 if
133 a return statement with no argument is seen. */
134
135 int current_function_returns_null;
136
137 /* Set to 0 at beginning of a function definition, set to 1 if
138 a call to a noreturn function is seen. */
139
140 int current_function_returns_abnormally;
141
142 /* Set to nonzero by `grokdeclarator' for a function
143 whose return type is defaulted, if warnings for this are desired. */
144
145 static int warn_about_return_type;
146
147 /* Nonzero when starting a function declared `extern inline'. */
148
149 static int current_extern_inline;
150 \f
151 /* For each binding contour we allocate a binding_level structure
152 * which records the names defined in that contour.
153 * Contours include:
154 * 0) the global one
155 * 1) one for each function definition,
156 * where internal declarations of the parameters appear.
157 * 2) one for each compound statement,
158 * to record its declarations.
159 *
160 * The current meaning of a name can be found by searching the levels from
161 * the current one out to the global one.
162 */
163
164 /* Note that the information in the `names' component of the global contour
165 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */
166
167 struct binding_level GTY(())
168 {
169 /* A chain of _DECL nodes for all variables, constants, functions,
170 and typedef types. These are in the reverse of the order supplied.
171 */
172 tree names;
173
174 /* A list of structure, union and enum definitions,
175 * for looking up tag names.
176 * It is a chain of TREE_LIST nodes, each of whose TREE_PURPOSE is a name,
177 * or NULL_TREE; and whose TREE_VALUE is a RECORD_TYPE, UNION_TYPE,
178 * or ENUMERAL_TYPE node.
179 */
180 tree tags;
181
182 /* For each level, a list of shadowed outer-level local definitions
183 to be restored when this level is popped.
184 Each link is a TREE_LIST whose TREE_PURPOSE is an identifier and
185 whose TREE_VALUE is its old definition (a kind of ..._DECL node). */
186 tree shadowed;
187
188 /* For each level (except not the global one),
189 a chain of BLOCK nodes for all the levels
190 that were entered and exited one level down. */
191 tree blocks;
192
193 /* The BLOCK node for this level, if one has been preallocated.
194 If 0, the BLOCK is allocated (if needed) when the level is popped. */
195 tree this_block;
196
197 /* The binding level which this one is contained in (inherits from). */
198 struct binding_level *level_chain;
199
200 /* Nonzero for the level that holds the parameters of a function. */
201 char parm_flag;
202
203 /* Nonzero if this level "doesn't exist" for tags. */
204 char tag_transparent;
205
206 /* Nonzero if sublevels of this level "don't exist" for tags.
207 This is set in the parm level of a function definition
208 while reading the function body, so that the outermost block
209 of the function body will be tag-transparent. */
210 char subblocks_tag_transparent;
211
212 /* Nonzero means make a BLOCK for this level regardless of all else. */
213 char keep;
214
215 /* Nonzero means make a BLOCK if this level has any subblocks. */
216 char keep_if_subblocks;
217
218 /* List of decls in `names' that have incomplete structure or
219 union types. */
220 tree incomplete_list;
221
222 /* A list of decls giving the (reversed) specified order of parms,
223 not including any forward-decls in the parmlist.
224 This is so we can put the parms in proper order for assign_parms. */
225 tree parm_order;
226 };
227
228 #define NULL_BINDING_LEVEL (struct binding_level *) NULL
229
230 /* The binding level currently in effect. */
231
232 static GTY(()) struct binding_level *current_binding_level;
233
234 /* A chain of binding_level structures awaiting reuse. */
235
236 static GTY((deletable (""))) struct binding_level *free_binding_level;
237
238 /* The outermost binding level, for names of file scope.
239 This is created when the compiler is started and exists
240 through the entire run. */
241
242 static GTY(()) struct binding_level *global_binding_level;
243
244 /* Binding level structures are initialized by copying this one. */
245
246 static struct binding_level clear_binding_level
247 = {NULL, NULL, NULL, NULL, NULL, NULL_BINDING_LEVEL, 0, 0, 0, 0, 0, NULL,
248 NULL};
249
250 /* Nonzero means unconditionally make a BLOCK for the next level pushed. */
251
252 static int keep_next_level_flag;
253
254 /* Nonzero means make a BLOCK for the next level pushed
255 if it has subblocks. */
256
257 static int keep_next_if_subblocks;
258
259 /* The chain of outer levels of label scopes.
260 This uses the same data structure used for binding levels,
261 but it works differently: each link in the chain records
262 saved values of named_labels and shadowed_labels for
263 a label binding level outside the current one. */
264
265 static GTY(()) struct binding_level *label_level_chain;
266
267 /* Functions called automatically at the beginning and end of execution. */
268
269 tree static_ctors, static_dtors;
270
271 /* Forward declarations. */
272
273 static struct binding_level * make_binding_level PARAMS ((void));
274 static void pop_binding_level PARAMS ((struct binding_level **));
275 static void clear_limbo_values PARAMS ((tree));
276 static int duplicate_decls PARAMS ((tree, tree, int));
277 static int redeclaration_error_message PARAMS ((tree, tree));
278 static void storedecls PARAMS ((tree));
279 static void storetags PARAMS ((tree));
280 static tree lookup_tag PARAMS ((enum tree_code, tree,
281 struct binding_level *, int));
282 static tree lookup_tag_reverse PARAMS ((tree));
283 static tree grokdeclarator PARAMS ((tree, tree, enum decl_context,
284 int));
285 static tree grokparms PARAMS ((tree, int));
286 static void layout_array_type PARAMS ((tree));
287 static tree c_make_fname_decl PARAMS ((tree, int));
288 static void c_expand_body PARAMS ((tree, int, int));
289 static void warn_if_shadowing PARAMS ((tree, tree));
290 \f
291 /* C-specific option variables. */
292
293 /* Nonzero means allow type mismatches in conditional expressions;
294 just make their values `void'. */
295
296 int flag_cond_mismatch;
297
298 /* Nonzero means don't recognize the keyword `asm'. */
299
300 int flag_no_asm;
301
302 /* Nonzero means enable C89 Amendment 1 features. */
303
304 int flag_isoc94 = 0;
305
306 /* Nonzero means use the ISO C99 dialect of C. */
307
308 int flag_isoc99 = 0;
309
310 /* Nonzero means that we have builtin functions, and main is an int */
311
312 int flag_hosted = 1;
313
314 /* Nonzero means add default format_arg attributes for functions not
315 in ISO C. */
316
317 int flag_noniso_default_format_attributes = 1;
318
319 /* Nonzero means to treat bitfields as signed unless they say `unsigned'. */
320
321 int flag_signed_bitfields = 1;
322 int explicit_flag_signed_bitfields = 0;
323
324 /* Nonzero means warn about use of implicit int. */
325
326 int warn_implicit_int;
327
328 /* Nonzero means warn about usage of long long when `-pedantic'. */
329
330 int warn_long_long = 1;
331
332 /* Nonzero means message about use of implicit function declarations;
333 1 means warning; 2 means error. */
334
335 int mesg_implicit_function_declaration = -1;
336
337 /* Nonzero means give string constants the type `const char *'
338 to get extra warnings from them. These warnings will be too numerous
339 to be useful, except in thoroughly ANSIfied programs. */
340
341 int flag_const_strings;
342
343 /* Nonzero means warn about pointer casts that can drop a type qualifier
344 from the pointer target type. */
345
346 int warn_cast_qual;
347
348 /* Nonzero means warn when casting a function call to a type that does
349 not match the return type (e.g. (float)sqrt() or (anything*)malloc()
350 when there is no previous declaration of sqrt or malloc. */
351
352 int warn_bad_function_cast;
353
354 /* Warn about functions which might be candidates for format attributes. */
355
356 int warn_missing_format_attribute;
357
358 /* Warn about traditional constructs whose meanings changed in ANSI C. */
359
360 int warn_traditional;
361
362 /* Nonzero means warn about sizeof(function) or addition/subtraction
363 of function pointers. */
364
365 int warn_pointer_arith;
366
367 /* Nonzero means warn for non-prototype function decls
368 or non-prototyped defs without previous prototype. */
369
370 int warn_strict_prototypes;
371
372 /* Nonzero means warn for any global function def
373 without separate previous prototype decl. */
374
375 int warn_missing_prototypes;
376
377 /* Nonzero means warn for any global function def
378 without separate previous decl. */
379
380 int warn_missing_declarations;
381
382 /* Nonzero means warn about multiple (redundant) decls for the same single
383 variable or function. */
384
385 int warn_redundant_decls = 0;
386
387 /* Nonzero means warn about extern declarations of objects not at
388 file-scope level and about *all* declarations of functions (whether
389 extern or static) not at file-scope level. Note that we exclude
390 implicit function declarations. To get warnings about those, use
391 -Wimplicit. */
392
393 int warn_nested_externs = 0;
394
395 /* Warn about a subscript that has type char. */
396
397 int warn_char_subscripts = 0;
398
399 /* Warn if a type conversion is done that might have confusing results. */
400
401 int warn_conversion;
402
403 /* Warn if adding () is suggested. */
404
405 int warn_parentheses;
406
407 /* Warn if initializer is not completely bracketed. */
408
409 int warn_missing_braces;
410
411 /* Warn if main is suspicious. */
412
413 int warn_main;
414
415 /* Warn about #pragma directives that are not recognised. */
416
417 int warn_unknown_pragmas = 0; /* Tri state variable. */
418
419 /* Warn about comparison of signed and unsigned values.
420 If -1, neither -Wsign-compare nor -Wno-sign-compare has been specified. */
421
422 int warn_sign_compare = -1;
423
424 /* Warn about testing equality of floating point numbers. */
425
426 int warn_float_equal = 0;
427
428 /* Nonzero means `$' can be in an identifier. */
429
430 #ifndef DOLLARS_IN_IDENTIFIERS
431 #define DOLLARS_IN_IDENTIFIERS 1
432 #endif
433 int dollars_in_ident = DOLLARS_IN_IDENTIFIERS;
434
435 /* States indicating how grokdeclarator() should handle declspecs marked
436 with __attribute__((deprecated)). An object declared as
437 __attribute__((deprecated)) suppresses warnings of uses of other
438 deprecated items. */
439
440 enum deprecated_states {
441 DEPRECATED_NORMAL,
442 DEPRECATED_SUPPRESS
443 };
444
445 static enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
446
447 /* Decode the string P as a language-specific option for C.
448 Return the number of strings consumed. Should not complain
449 if it does not recognise the option. */
450
451 int
452 c_decode_option (argc, argv)
453 int argc ATTRIBUTE_UNUSED;
454 char **argv;
455 {
456 int strings_processed;
457 char *p = argv[0];
458
459 static const struct {
460 /* The name of the option. */
461 const char *option;
462 /* If non-NULL, a flag variable to set to 0 or 1. If NULL,
463 this means that cpp handles this option. */
464 int *flag;
465 } warn_options[] = {
466 /* This list is in alphabetical order. Keep it like that. */
467 { "bad-function-cast", &warn_bad_function_cast },
468 { "cast-qual", &warn_cast_qual },
469 { "char-subscripts", &warn_char_subscripts },
470 { "comment", NULL },
471 { "comments", NULL },
472 { "conversion", &warn_conversion },
473 { "div-by-zero", &warn_div_by_zero },
474 { "float-equal", &warn_float_equal },
475 { "format-extra-args", &warn_format_extra_args },
476 { "format-zero-length", &warn_format_zero_length },
477 { "format-nonliteral", &warn_format_nonliteral },
478 { "format-security", &warn_format_security },
479 { "format-y2k", &warn_format_y2k },
480 { "implicit-function-declaration", &mesg_implicit_function_declaration },
481 { "implicit-int", &warn_implicit_int },
482 { "import", NULL },
483 { "long-long", &warn_long_long },
484 { "main", &warn_main },
485 { "missing-braces", &warn_missing_braces },
486 { "missing-declarations", &warn_missing_declarations },
487 { "missing-format-attribute", &warn_missing_format_attribute },
488 { "missing-prototypes", &warn_missing_prototypes },
489 { "multichar", &warn_multichar },
490 { "nested-externs", &warn_nested_externs },
491 { "nonnull", &warn_nonnull },
492 { "parentheses", &warn_parentheses },
493 { "pointer-arith", &warn_pointer_arith },
494 { "redundant-decls", &warn_redundant_decls },
495 { "return-type", &warn_return_type },
496 { "sequence-point", &warn_sequence_point },
497 { "sign-compare", &warn_sign_compare },
498 { "strict-prototypes", &warn_strict_prototypes },
499 { "traditional", &warn_traditional },
500 { "trigraphs", NULL },
501 { "undef", NULL },
502 { "write-strings", &flag_const_strings }
503 };
504
505 strings_processed = cpp_handle_option (parse_in, argc, argv);
506
507 if (!strcmp (p, "-fhosted") || !strcmp (p, "-fno-freestanding"))
508 {
509 flag_hosted = 1;
510 flag_no_builtin = 0;
511 }
512 else if (!strcmp (p, "-ffreestanding") || !strcmp (p, "-fno-hosted"))
513 {
514 flag_hosted = 0;
515 flag_no_builtin = 1;
516 /* warn_main will be 2 if set by -Wall, 1 if set by -Wmain */
517 if (warn_main == 2)
518 warn_main = 0;
519 }
520 else if (!strncmp (p, "-std=", 5))
521 {
522 /* Select the appropriate language standard. We currently
523 recognize:
524 -std=iso9899:1990 same as -ansi
525 -std=iso9899:199409 ISO C as modified in amend. 1
526 -std=iso9899:1999 ISO C 99
527 -std=c89 same as -std=iso9899:1990
528 -std=c99 same as -std=iso9899:1999
529 -std=gnu89 default, iso9899:1990 + gnu extensions
530 -std=gnu99 iso9899:1999 + gnu extensions
531 */
532 const char *const argstart = &p[5];
533
534 if (!strcmp (argstart, "iso9899:1990")
535 || !strcmp (argstart, "c89"))
536 {
537 iso_1990:
538 flag_isoc94 = 0;
539 iso_1994:
540 flag_writable_strings = 0;
541 flag_no_asm = 1;
542 flag_no_nonansi_builtin = 1;
543 flag_noniso_default_format_attributes = 0;
544 flag_isoc99 = 0;
545 flag_iso = 1;
546 }
547 else if (!strcmp (argstart, "iso9899:199409"))
548 {
549 flag_isoc94 = 1;
550 goto iso_1994;
551 }
552 else if (!strcmp (argstart, "iso9899:199x")
553 || !strcmp (argstart, "iso9899:1999")
554 || !strcmp (argstart, "c9x")
555 || !strcmp (argstart, "c99"))
556 {
557 flag_writable_strings = 0;
558 flag_no_asm = 1;
559 flag_no_nonansi_builtin = 1;
560 flag_noniso_default_format_attributes = 0;
561 flag_isoc99 = 1;
562 flag_isoc94 = 1;
563 flag_iso = 1;
564 }
565 else if (!strcmp (argstart, "gnu89"))
566 {
567 flag_writable_strings = 0;
568 flag_no_asm = 0;
569 flag_no_nonansi_builtin = 0;
570 flag_noniso_default_format_attributes = 1;
571 flag_isoc99 = 0;
572 flag_isoc94 = 0;
573 }
574 else if (!strcmp (argstart, "gnu9x") || !strcmp (argstart, "gnu99"))
575 {
576 flag_writable_strings = 0;
577 flag_no_asm = 0;
578 flag_no_nonansi_builtin = 0;
579 flag_noniso_default_format_attributes = 1;
580 flag_isoc99 = 1;
581 flag_isoc94 = 1;
582 }
583 else if (!strcmp (argstart, "c++98"))
584 ; /* Handled by cpplib. */
585 else
586 error ("unknown C standard `%s'", argstart);
587 }
588 else if (!strcmp (p, "-fdollars-in-identifiers"))
589 dollars_in_ident = 1;
590 else if (!strcmp (p, "-fno-dollars-in-identifiers"))
591 dollars_in_ident = 0;
592 else if (!strcmp (p, "-fsigned-char"))
593 flag_signed_char = 1;
594 else if (!strcmp (p, "-funsigned-char"))
595 flag_signed_char = 0;
596 else if (!strcmp (p, "-fno-signed-char"))
597 flag_signed_char = 0;
598 else if (!strcmp (p, "-fno-unsigned-char"))
599 flag_signed_char = 1;
600 else if (!strcmp (p, "-fsigned-bitfields")
601 || !strcmp (p, "-fno-unsigned-bitfields"))
602 {
603 flag_signed_bitfields = 1;
604 explicit_flag_signed_bitfields = 1;
605 }
606 else if (!strcmp (p, "-funsigned-bitfields")
607 || !strcmp (p, "-fno-signed-bitfields"))
608 {
609 flag_signed_bitfields = 0;
610 explicit_flag_signed_bitfields = 1;
611 }
612 else if (!strcmp (p, "-fshort-enums"))
613 flag_short_enums = 1;
614 else if (!strcmp (p, "-fno-short-enums"))
615 flag_short_enums = 0;
616 else if (!strcmp (p, "-fshort-wchar"))
617 flag_short_wchar = 1;
618 else if (!strcmp (p, "-fno-short-wchar"))
619 flag_short_wchar = 0;
620 else if (!strcmp (p, "-fcond-mismatch"))
621 flag_cond_mismatch = 1;
622 else if (!strcmp (p, "-fno-cond-mismatch"))
623 flag_cond_mismatch = 0;
624 else if (!strcmp (p, "-fshort-double"))
625 flag_short_double = 1;
626 else if (!strcmp (p, "-fno-short-double"))
627 flag_short_double = 0;
628 else if (!strcmp (p, "-fasm"))
629 flag_no_asm = 0;
630 else if (!strcmp (p, "-fno-asm"))
631 flag_no_asm = 1;
632 else if (!strcmp (p, "-fbuiltin"))
633 flag_no_builtin = 0;
634 else if (!strcmp (p, "-fno-builtin"))
635 flag_no_builtin = 1;
636 else if (!strncmp (p, "-fno-builtin-", strlen ("-fno-builtin-")))
637 disable_builtin_function (p + strlen ("-fno-builtin-"));
638 else if (p[0] == '-' && p[1] == 'f' && dump_switch_p (p + 2))
639 ;
640 else if (!strcmp (p, "-ansi"))
641 goto iso_1990;
642 else if (!strcmp (p, "-undef"))
643 flag_undef = 1;
644 else if (!strcmp (p, "-Werror-implicit-function-declaration"))
645 mesg_implicit_function_declaration = 2;
646 else if (!strncmp (p, "-Wformat=", 9))
647 set_Wformat (atoi (p + 9));
648 else if (!strcmp (p, "-Wformat"))
649 set_Wformat (1);
650 else if (!strcmp (p, "-Wno-format"))
651 set_Wformat (0);
652 else if (!strcmp (p, "-Wimplicit"))
653 {
654 warn_implicit_int = 1;
655 if (mesg_implicit_function_declaration != 2)
656 mesg_implicit_function_declaration = 1;
657 }
658 else if (!strcmp (p, "-Wno-implicit"))
659 warn_implicit_int = 0, mesg_implicit_function_declaration = 0;
660 else if (!strcmp (p, "-Wno-main"))
661 warn_main = -1;
662 else if (!strcmp (p, "-Wunknown-pragmas"))
663 /* Set to greater than 1, so that even unknown pragmas in system
664 headers will be warned about. */
665 warn_unknown_pragmas = 2;
666 else if (!strcmp (p, "-Wno-unknown-pragmas"))
667 warn_unknown_pragmas = 0;
668 else if (!strcmp (p, "-Wall"))
669 {
670 /* We save the value of warn_uninitialized, since if they put
671 -Wuninitialized on the command line, we need to generate a
672 warning about not using it without also specifying -O. */
673 if (warn_uninitialized != 1)
674 warn_uninitialized = 2;
675 warn_implicit_int = 1;
676 mesg_implicit_function_declaration = 1;
677 warn_return_type = 1;
678 set_Wunused (1);
679 warn_switch = 1;
680 set_Wformat (1);
681 warn_char_subscripts = 1;
682 warn_parentheses = 1;
683 warn_sequence_point = 1;
684 warn_missing_braces = 1;
685 /* We set this to 2 here, but 1 in -Wmain, so -ffreestanding can turn
686 it off only if it's not explicit. */
687 warn_main = 2;
688 /* Only warn about unknown pragmas that are not in system headers. */
689 warn_unknown_pragmas = 1;
690 }
691 else if (!strcmp (p, "-E"))
692 flag_preprocess_only = 1;
693 else
694 {
695 size_t i;
696 for (i = 0; i < sizeof (warn_options) / sizeof (warn_options[0]); i++)
697 if (strncmp (p, "-W", 2) == 0
698 && warn_options[i].flag
699 && (strcmp (p+2, warn_options[i].option) == 0
700 || (strncmp (p+2, "no-", 3) == 0
701 && strcmp (p+5, warn_options[i].option) == 0)))
702 {
703 *(warn_options[i].flag) = strncmp (p+2, "no-", 3) != 0;
704 return 1;
705 }
706 return strings_processed;
707 }
708
709 return 1;
710 }
711
712 void
713 c_print_identifier (file, node, indent)
714 FILE *file;
715 tree node;
716 int indent;
717 {
718 print_node (file, "global", IDENTIFIER_GLOBAL_VALUE (node), indent + 4);
719 print_node (file, "local", IDENTIFIER_LOCAL_VALUE (node), indent + 4);
720 print_node (file, "label", IDENTIFIER_LABEL_VALUE (node), indent + 4);
721 print_node (file, "implicit", IDENTIFIER_IMPLICIT_DECL (node), indent + 4);
722 print_node (file, "error locus", IDENTIFIER_ERROR_LOCUS (node), indent + 4);
723 print_node (file, "limbo value", IDENTIFIER_LIMBO_VALUE (node), indent + 4);
724 if (C_IS_RESERVED_WORD (node))
725 {
726 tree rid = ridpointers[C_RID_CODE (node)];
727 indent_to (file, indent + 4);
728 fprintf (file, "rid ");
729 fprintf (file, HOST_PTR_PRINTF, (void *)rid);
730 fprintf (file, " \"%s\"", IDENTIFIER_POINTER (rid));
731 }
732 }
733 \f
734 /* Hook called at end of compilation to assume 1 elt
735 for a top-level tentative array defn that wasn't complete before. */
736
737 void
738 c_finish_incomplete_decl (decl)
739 tree decl;
740 {
741 if (TREE_CODE (decl) == VAR_DECL)
742 {
743 tree type = TREE_TYPE (decl);
744 if (type != error_mark_node
745 && TREE_CODE (type) == ARRAY_TYPE
746 && ! DECL_EXTERNAL (decl)
747 && TYPE_DOMAIN (type) == 0)
748 {
749 warning_with_decl (decl, "array `%s' assumed to have one element");
750
751 complete_array_type (type, NULL_TREE, 1);
752
753 layout_decl (decl, 0);
754 }
755 }
756 }
757 \f
758 /* Reuse or create a struct for this binding level. */
759
760 static struct binding_level *
761 make_binding_level ()
762 {
763 if (free_binding_level)
764 {
765 struct binding_level *result = free_binding_level;
766 free_binding_level = result->level_chain;
767 return result;
768 }
769 else
770 return (struct binding_level *) ggc_alloc (sizeof (struct binding_level));
771 }
772
773 /* Remove a binding level from a list and add it to the level chain. */
774
775 static void
776 pop_binding_level (lp)
777 struct binding_level **lp;
778 {
779 struct binding_level *l = *lp;
780 *lp = l->level_chain;
781
782 memset (l, 0, sizeof (struct binding_level));
783 l->level_chain = free_binding_level;
784 free_binding_level = l;
785 }
786
787 /* Nonzero if we are currently in the global binding level. */
788
789 int
790 global_bindings_p ()
791 {
792 return current_binding_level == global_binding_level;
793 }
794
795 void
796 keep_next_level ()
797 {
798 keep_next_level_flag = 1;
799 }
800
801 /* Nonzero if the current level needs to have a BLOCK made. */
802
803 int
804 kept_level_p ()
805 {
806 return ((current_binding_level->keep_if_subblocks
807 && current_binding_level->blocks != 0)
808 || current_binding_level->keep
809 || current_binding_level->names != 0
810 || (current_binding_level->tags != 0
811 && !current_binding_level->tag_transparent));
812 }
813
814 /* Identify this binding level as a level of parameters.
815 DEFINITION_FLAG is 1 for a definition, 0 for a declaration.
816 But it turns out there is no way to pass the right value for
817 DEFINITION_FLAG, so we ignore it. */
818
819 void
820 declare_parm_level (definition_flag)
821 int definition_flag ATTRIBUTE_UNUSED;
822 {
823 current_binding_level->parm_flag = 1;
824 }
825
826 /* Nonzero if currently making parm declarations. */
827
828 int
829 in_parm_level_p ()
830 {
831 return current_binding_level->parm_flag;
832 }
833
834 /* Enter a new binding level.
835 If TAG_TRANSPARENT is nonzero, do so only for the name space of variables,
836 not for that of tags. */
837
838 void
839 pushlevel (tag_transparent)
840 int tag_transparent;
841 {
842 struct binding_level *newlevel = NULL_BINDING_LEVEL;
843
844 /* If this is the top level of a function,
845 just make sure that NAMED_LABELS is 0. */
846
847 if (current_binding_level == global_binding_level)
848 {
849 named_labels = 0;
850 }
851
852 newlevel = make_binding_level ();
853
854 /* Add this level to the front of the chain (stack) of levels that
855 are active. */
856
857 *newlevel = clear_binding_level;
858 newlevel->tag_transparent
859 = (tag_transparent
860 || (current_binding_level
861 ? current_binding_level->subblocks_tag_transparent
862 : 0));
863 newlevel->level_chain = current_binding_level;
864 current_binding_level = newlevel;
865 newlevel->keep = keep_next_level_flag;
866 keep_next_level_flag = 0;
867 newlevel->keep_if_subblocks = keep_next_if_subblocks;
868 keep_next_if_subblocks = 0;
869 }
870
871 /* Clear the limbo values of all identifiers defined in BLOCK or a subblock. */
872
873 static void
874 clear_limbo_values (block)
875 tree block;
876 {
877 tree tem;
878
879 for (tem = BLOCK_VARS (block); tem; tem = TREE_CHAIN (tem))
880 if (DECL_NAME (tem) != 0)
881 IDENTIFIER_LIMBO_VALUE (DECL_NAME (tem)) = 0;
882
883 for (tem = BLOCK_SUBBLOCKS (block); tem; tem = TREE_CHAIN (tem))
884 clear_limbo_values (tem);
885 }
886
887 /* Exit a binding level.
888 Pop the level off, and restore the state of the identifier-decl mappings
889 that were in effect when this level was entered.
890
891 If KEEP is nonzero, this level had explicit declarations, so
892 and create a "block" (a BLOCK node) for the level
893 to record its declarations and subblocks for symbol table output.
894
895 If FUNCTIONBODY is nonzero, this level is the body of a function,
896 so create a block as if KEEP were set and also clear out all
897 label names.
898
899 If REVERSE is nonzero, reverse the order of decls before putting
900 them into the BLOCK. */
901
902 tree
903 poplevel (keep, reverse, functionbody)
904 int keep;
905 int reverse;
906 int functionbody;
907 {
908 tree link;
909 /* The chain of decls was accumulated in reverse order.
910 Put it into forward order, just for cleanliness. */
911 tree decls;
912 tree tags = current_binding_level->tags;
913 tree subblocks = current_binding_level->blocks;
914 tree block = 0;
915 tree decl;
916 int block_previously_created;
917
918 keep |= current_binding_level->keep;
919
920 /* This warning is turned off because it causes warnings for
921 declarations like `extern struct foo *x'. */
922 #if 0
923 /* Warn about incomplete structure types in this level. */
924 for (link = tags; link; link = TREE_CHAIN (link))
925 if (!COMPLETE_TYPE_P (TREE_VALUE (link)))
926 {
927 tree type = TREE_VALUE (link);
928 tree type_name = TYPE_NAME (type);
929 char *id = IDENTIFIER_POINTER (TREE_CODE (type_name) == IDENTIFIER_NODE
930 ? type_name
931 : DECL_NAME (type_name));
932 switch (TREE_CODE (type))
933 {
934 case RECORD_TYPE:
935 error ("`struct %s' incomplete in scope ending here", id);
936 break;
937 case UNION_TYPE:
938 error ("`union %s' incomplete in scope ending here", id);
939 break;
940 case ENUMERAL_TYPE:
941 error ("`enum %s' incomplete in scope ending here", id);
942 break;
943 }
944 }
945 #endif /* 0 */
946
947 /* Get the decls in the order they were written.
948 Usually current_binding_level->names is in reverse order.
949 But parameter decls were previously put in forward order. */
950
951 if (reverse)
952 current_binding_level->names
953 = decls = nreverse (current_binding_level->names);
954 else
955 decls = current_binding_level->names;
956
957 /* Output any nested inline functions within this block
958 if they weren't already output. */
959
960 for (decl = decls; decl; decl = TREE_CHAIN (decl))
961 if (TREE_CODE (decl) == FUNCTION_DECL
962 && ! TREE_ASM_WRITTEN (decl)
963 && DECL_INITIAL (decl) != 0
964 && TREE_ADDRESSABLE (decl))
965 {
966 /* If this decl was copied from a file-scope decl
967 on account of a block-scope extern decl,
968 propagate TREE_ADDRESSABLE to the file-scope decl.
969
970 DECL_ABSTRACT_ORIGIN can be set to itself if warn_return_type is
971 true, since then the decl goes through save_for_inline_copying. */
972 if (DECL_ABSTRACT_ORIGIN (decl) != 0
973 && DECL_ABSTRACT_ORIGIN (decl) != decl)
974 TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (decl)) = 1;
975 }
976
977 /* We used to warn about unused variables in expand_end_bindings,
978 i.e. while generating RTL. But in function-at-a-time mode we may
979 choose to never expand a function at all (e.g. auto inlining), so
980 we do this explicitly now. */
981 warn_about_unused_variables (getdecls ());
982
983 /* If there were any declarations or structure tags in that level,
984 or if this level is a function body,
985 create a BLOCK to record them for the life of this function. */
986
987 block = 0;
988 block_previously_created = (current_binding_level->this_block != 0);
989 if (block_previously_created)
990 block = current_binding_level->this_block;
991 else if (keep || functionbody
992 || (current_binding_level->keep_if_subblocks && subblocks != 0))
993 block = make_node (BLOCK);
994 if (block != 0)
995 {
996 BLOCK_VARS (block) = decls;
997 BLOCK_SUBBLOCKS (block) = subblocks;
998 }
999
1000 /* In each subblock, record that this is its superior. */
1001
1002 for (link = subblocks; link; link = TREE_CHAIN (link))
1003 BLOCK_SUPERCONTEXT (link) = block;
1004
1005 /* Clear out the meanings of the local variables of this level. */
1006
1007 for (link = decls; link; link = TREE_CHAIN (link))
1008 {
1009 if (DECL_NAME (link) != 0)
1010 {
1011 /* If the ident. was used or addressed via a local extern decl,
1012 don't forget that fact. */
1013 if (DECL_EXTERNAL (link))
1014 {
1015 if (TREE_USED (link))
1016 TREE_USED (DECL_NAME (link)) = 1;
1017 if (TREE_ADDRESSABLE (link))
1018 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (link)) = 1;
1019 }
1020 IDENTIFIER_LOCAL_VALUE (DECL_NAME (link)) = 0;
1021 }
1022 }
1023
1024 /* Restore all name-meanings of the outer levels
1025 that were shadowed by this level. */
1026
1027 for (link = current_binding_level->shadowed; link; link = TREE_CHAIN (link))
1028 IDENTIFIER_LOCAL_VALUE (TREE_PURPOSE (link)) = TREE_VALUE (link);
1029
1030 /* If the level being exited is the top level of a function,
1031 check over all the labels, and clear out the current
1032 (function local) meanings of their names. */
1033
1034 if (functionbody)
1035 {
1036 clear_limbo_values (block);
1037
1038 /* If this is the top level block of a function,
1039 the vars are the function's parameters.
1040 Don't leave them in the BLOCK because they are
1041 found in the FUNCTION_DECL instead. */
1042
1043 BLOCK_VARS (block) = 0;
1044
1045 /* Clear out the definitions of all label names,
1046 since their scopes end here,
1047 and add them to BLOCK_VARS. */
1048
1049 for (link = named_labels; link; link = TREE_CHAIN (link))
1050 {
1051 tree label = TREE_VALUE (link);
1052
1053 if (DECL_INITIAL (label) == 0)
1054 {
1055 error_with_decl (label, "label `%s' used but not defined");
1056 /* Avoid crashing later. */
1057 define_label (input_filename, lineno,
1058 DECL_NAME (label));
1059 }
1060 else if (warn_unused_label && !TREE_USED (label))
1061 warning_with_decl (label, "label `%s' defined but not used");
1062 IDENTIFIER_LABEL_VALUE (DECL_NAME (label)) = 0;
1063
1064 /* Put the labels into the "variables" of the
1065 top-level block, so debugger can see them. */
1066 TREE_CHAIN (label) = BLOCK_VARS (block);
1067 BLOCK_VARS (block) = label;
1068 }
1069 }
1070
1071 /* Pop the current level, and free the structure for reuse. */
1072
1073 pop_binding_level (&current_binding_level);
1074
1075 /* Dispose of the block that we just made inside some higher level. */
1076 if (functionbody)
1077 DECL_INITIAL (current_function_decl) = block;
1078 else if (block)
1079 {
1080 if (!block_previously_created)
1081 current_binding_level->blocks
1082 = chainon (current_binding_level->blocks, block);
1083 }
1084 /* If we did not make a block for the level just exited,
1085 any blocks made for inner levels
1086 (since they cannot be recorded as subblocks in that level)
1087 must be carried forward so they will later become subblocks
1088 of something else. */
1089 else if (subblocks)
1090 current_binding_level->blocks
1091 = chainon (current_binding_level->blocks, subblocks);
1092
1093 /* Set the TYPE_CONTEXTs for all of the tagged types belonging to this
1094 binding contour so that they point to the appropriate construct, i.e.
1095 either to the current FUNCTION_DECL node, or else to the BLOCK node
1096 we just constructed.
1097
1098 Note that for tagged types whose scope is just the formal parameter
1099 list for some function type specification, we can't properly set
1100 their TYPE_CONTEXTs here, because we don't have a pointer to the
1101 appropriate FUNCTION_TYPE node readily available to us. For those
1102 cases, the TYPE_CONTEXTs of the relevant tagged type nodes get set
1103 in `grokdeclarator' as soon as we have created the FUNCTION_TYPE
1104 node which will represent the "scope" for these "parameter list local"
1105 tagged types. */
1106
1107 if (functionbody)
1108 for (link = tags; link; link = TREE_CHAIN (link))
1109 TYPE_CONTEXT (TREE_VALUE (link)) = current_function_decl;
1110 else if (block)
1111 for (link = tags; link; link = TREE_CHAIN (link))
1112 TYPE_CONTEXT (TREE_VALUE (link)) = block;
1113
1114 if (block)
1115 TREE_USED (block) = 1;
1116
1117 return block;
1118 }
1119
1120 /* Insert BLOCK at the end of the list of subblocks of the
1121 current binding level. This is used when a BIND_EXPR is expanded,
1122 to handle the BLOCK node inside the BIND_EXPR. */
1123
1124 void
1125 insert_block (block)
1126 tree block;
1127 {
1128 TREE_USED (block) = 1;
1129 current_binding_level->blocks
1130 = chainon (current_binding_level->blocks, block);
1131 }
1132
1133 /* Set the BLOCK node for the innermost scope
1134 (the one we are currently in). */
1135
1136 void
1137 set_block (block)
1138 tree block;
1139 {
1140 current_binding_level->this_block = block;
1141 current_binding_level->names = chainon (current_binding_level->names,
1142 BLOCK_VARS (block));
1143 current_binding_level->blocks = chainon (current_binding_level->blocks,
1144 BLOCK_SUBBLOCKS (block));
1145 }
1146 \f
1147 void
1148 push_label_level ()
1149 {
1150 struct binding_level *newlevel;
1151
1152 newlevel = make_binding_level ();
1153
1154 /* Add this level to the front of the chain (stack) of label levels. */
1155
1156 newlevel->level_chain = label_level_chain;
1157 label_level_chain = newlevel;
1158
1159 newlevel->names = named_labels;
1160 newlevel->shadowed = shadowed_labels;
1161 named_labels = 0;
1162 shadowed_labels = 0;
1163 }
1164
1165 void
1166 pop_label_level ()
1167 {
1168 struct binding_level *level = label_level_chain;
1169 tree link, prev;
1170
1171 /* Clear out the definitions of the declared labels in this level.
1172 Leave in the list any ordinary, non-declared labels. */
1173 for (link = named_labels, prev = 0; link;)
1174 {
1175 if (C_DECLARED_LABEL_FLAG (TREE_VALUE (link)))
1176 {
1177 if (DECL_SOURCE_LINE (TREE_VALUE (link)) == 0)
1178 {
1179 error_with_decl (TREE_VALUE (link),
1180 "label `%s' used but not defined");
1181 /* Avoid crashing later. */
1182 define_label (input_filename, lineno,
1183 DECL_NAME (TREE_VALUE (link)));
1184 }
1185 else if (warn_unused_label && !TREE_USED (TREE_VALUE (link)))
1186 warning_with_decl (TREE_VALUE (link),
1187 "label `%s' defined but not used");
1188 IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link))) = 0;
1189
1190 /* Delete this element from the list. */
1191 link = TREE_CHAIN (link);
1192 if (prev)
1193 TREE_CHAIN (prev) = link;
1194 else
1195 named_labels = link;
1196 }
1197 else
1198 {
1199 prev = link;
1200 link = TREE_CHAIN (link);
1201 }
1202 }
1203
1204 /* Bring back all the labels that were shadowed. */
1205 for (link = shadowed_labels; link; link = TREE_CHAIN (link))
1206 if (DECL_NAME (TREE_VALUE (link)) != 0)
1207 IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link)))
1208 = TREE_VALUE (link);
1209
1210 named_labels = chainon (named_labels, level->names);
1211 shadowed_labels = level->shadowed;
1212
1213 /* Pop the current level, and free the structure for reuse. */
1214 pop_binding_level (&label_level_chain);
1215 }
1216 \f
1217 /* Push a definition or a declaration of struct, union or enum tag "name".
1218 "type" should be the type node.
1219 We assume that the tag "name" is not already defined.
1220
1221 Note that the definition may really be just a forward reference.
1222 In that case, the TYPE_SIZE will be zero. */
1223
1224 void
1225 pushtag (name, type)
1226 tree name, type;
1227 {
1228 struct binding_level *b;
1229
1230 /* Find the proper binding level for this type tag. */
1231
1232 for (b = current_binding_level; b->tag_transparent; b = b->level_chain)
1233 continue;
1234
1235 if (name)
1236 {
1237 /* Record the identifier as the type's name if it has none. */
1238
1239 if (TYPE_NAME (type) == 0)
1240 TYPE_NAME (type) = name;
1241 }
1242
1243 b->tags = tree_cons (name, type, b->tags);
1244
1245 /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
1246 tagged type we just added to the current binding level. This fake
1247 NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
1248 to output a representation of a tagged type, and it also gives
1249 us a convenient place to record the "scope start" address for the
1250 tagged type. */
1251
1252 TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));
1253
1254 /* An approximation for now, so we can tell this is a function-scope tag.
1255 This will be updated in poplevel. */
1256 TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
1257 }
1258 \f
1259 /* Handle when a new declaration NEWDECL
1260 has the same name as an old one OLDDECL
1261 in the same binding contour.
1262 Prints an error message if appropriate.
1263
1264 If safely possible, alter OLDDECL to look like NEWDECL, and return 1.
1265 Otherwise, return 0.
1266
1267 When DIFFERENT_BINDING_LEVEL is true, NEWDECL is an external declaration,
1268 and OLDDECL is in an outer binding level and should thus not be changed. */
1269
1270 static int
1271 duplicate_decls (newdecl, olddecl, different_binding_level)
1272 tree newdecl, olddecl;
1273 int different_binding_level;
1274 {
1275 int types_match = comptypes (TREE_TYPE (newdecl), TREE_TYPE (olddecl));
1276 int new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
1277 && DECL_INITIAL (newdecl) != 0);
1278 tree oldtype = TREE_TYPE (olddecl);
1279 tree newtype = TREE_TYPE (newdecl);
1280 int errmsg = 0;
1281
1282 if (DECL_P (olddecl))
1283 {
1284 if (TREE_CODE (newdecl) == FUNCTION_DECL
1285 && TREE_CODE (olddecl) == FUNCTION_DECL
1286 && (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl)))
1287 {
1288 if (DECL_DECLARED_INLINE_P (newdecl)
1289 && DECL_UNINLINABLE (newdecl)
1290 && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1291 /* Already warned elsewhere. */;
1292 else if (DECL_DECLARED_INLINE_P (olddecl)
1293 && DECL_UNINLINABLE (olddecl)
1294 && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1295 /* Already warned. */;
1296 else if (DECL_DECLARED_INLINE_P (newdecl)
1297 && ! DECL_DECLARED_INLINE_P (olddecl)
1298 && DECL_UNINLINABLE (olddecl)
1299 && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1300 {
1301 warning_with_decl (newdecl,
1302 "function `%s' redeclared as inline");
1303 warning_with_decl (olddecl,
1304 "previous declaration of function `%s' with attribute noinline");
1305 }
1306 else if (DECL_DECLARED_INLINE_P (olddecl)
1307 && DECL_UNINLINABLE (newdecl)
1308 && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1309 {
1310 warning_with_decl (newdecl,
1311 "function `%s' redeclared with attribute noinline");
1312 warning_with_decl (olddecl,
1313 "previous declaration of function `%s' was inline");
1314 }
1315 }
1316
1317 DECL_ATTRIBUTES (newdecl)
1318 = (*targetm.merge_decl_attributes) (olddecl, newdecl);
1319 }
1320
1321 if (TREE_CODE (newtype) == ERROR_MARK
1322 || TREE_CODE (oldtype) == ERROR_MARK)
1323 types_match = 0;
1324
1325 /* New decl is completely inconsistent with the old one =>
1326 tell caller to replace the old one.
1327 This is always an error except in the case of shadowing a builtin. */
1328 if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1329 {
1330 if (TREE_CODE (olddecl) == FUNCTION_DECL
1331 && (DECL_BUILT_IN (olddecl)
1332 || DECL_BUILT_IN_NONANSI (olddecl)))
1333 {
1334 /* If you declare a built-in or predefined function name as static,
1335 the old definition is overridden,
1336 but optionally warn this was a bad choice of name. */
1337 if (!TREE_PUBLIC (newdecl))
1338 {
1339 if (!warn_shadow)
1340 ;
1341 else if (DECL_BUILT_IN (olddecl))
1342 warning_with_decl (newdecl, "shadowing built-in function `%s'");
1343 else
1344 warning_with_decl (newdecl, "shadowing library function `%s'");
1345 }
1346 /* Likewise, if the built-in is not ansi, then programs can
1347 override it even globally without an error. */
1348 else if (! DECL_BUILT_IN (olddecl))
1349 warning_with_decl (newdecl,
1350 "library function `%s' declared as non-function");
1351
1352 else if (DECL_BUILT_IN_NONANSI (olddecl))
1353 warning_with_decl (newdecl,
1354 "built-in function `%s' declared as non-function");
1355 else
1356 warning_with_decl (newdecl,
1357 "built-in function `%s' declared as non-function");
1358 }
1359 else
1360 {
1361 error_with_decl (newdecl, "`%s' redeclared as different kind of symbol");
1362 error_with_decl (olddecl, "previous declaration of `%s'");
1363 }
1364
1365 return 0;
1366 }
1367
1368 /* For real parm decl following a forward decl,
1369 return 1 so old decl will be reused. */
1370 if (types_match && TREE_CODE (newdecl) == PARM_DECL
1371 && TREE_ASM_WRITTEN (olddecl) && ! TREE_ASM_WRITTEN (newdecl))
1372 return 1;
1373
1374 /* The new declaration is the same kind of object as the old one.
1375 The declarations may partially match. Print warnings if they don't
1376 match enough. Ultimately, copy most of the information from the new
1377 decl to the old one, and keep using the old one. */
1378
1379 if (TREE_CODE (olddecl) == FUNCTION_DECL && DECL_BUILT_IN (olddecl))
1380 {
1381 /* A function declaration for a built-in function. */
1382 if (!TREE_PUBLIC (newdecl))
1383 {
1384 /* If you declare a built-in function name as static, the
1385 built-in definition is overridden,
1386 but optionally warn this was a bad choice of name. */
1387 if (warn_shadow)
1388 warning_with_decl (newdecl, "shadowing built-in function `%s'");
1389 /* Discard the old built-in function. */
1390 return 0;
1391 }
1392 else if (!types_match)
1393 {
1394 /* Accept the return type of the new declaration if same modes. */
1395 tree oldreturntype = TREE_TYPE (oldtype);
1396 tree newreturntype = TREE_TYPE (newtype);
1397
1398 if (TYPE_MODE (oldreturntype) == TYPE_MODE (newreturntype))
1399 {
1400 /* Function types may be shared, so we can't just modify
1401 the return type of olddecl's function type. */
1402 tree trytype
1403 = build_function_type (newreturntype,
1404 TYPE_ARG_TYPES (oldtype));
1405 trytype = build_type_attribute_variant (trytype,
1406 TYPE_ATTRIBUTES (oldtype));
1407
1408 types_match = comptypes (newtype, trytype);
1409 if (types_match)
1410 oldtype = trytype;
1411 }
1412 /* Accept harmless mismatch in first argument type also.
1413 This is for the ffs and fprintf builtins. */
1414 if (TYPE_ARG_TYPES (TREE_TYPE (newdecl)) != 0
1415 && TYPE_ARG_TYPES (oldtype) != 0
1416 && TREE_VALUE (TYPE_ARG_TYPES (newtype)) != 0
1417 && TREE_VALUE (TYPE_ARG_TYPES (oldtype)) != 0
1418 && (TYPE_MODE (TREE_VALUE (TYPE_ARG_TYPES (newtype)))
1419 == TYPE_MODE (TREE_VALUE (TYPE_ARG_TYPES (oldtype)))))
1420 {
1421 /* Function types may be shared, so we can't just modify
1422 the return type of olddecl's function type. */
1423 tree trytype
1424 = build_function_type (TREE_TYPE (oldtype),
1425 tree_cons (NULL_TREE,
1426 TREE_VALUE (TYPE_ARG_TYPES (newtype)),
1427 TREE_CHAIN (TYPE_ARG_TYPES (oldtype))));
1428 trytype = build_type_attribute_variant (trytype,
1429 TYPE_ATTRIBUTES (oldtype));
1430
1431 types_match = comptypes (newtype, trytype);
1432 if (types_match)
1433 oldtype = trytype;
1434 }
1435 if (! different_binding_level)
1436 TREE_TYPE (olddecl) = oldtype;
1437 }
1438 else if (TYPE_ARG_TYPES (oldtype) == NULL
1439 && TYPE_ARG_TYPES (newtype) != NULL)
1440 {
1441 /* For bcmp, bzero, fputs the builtin type has arguments not
1442 specified. Use the ones from the prototype so that type checking
1443 is done for them. */
1444 tree trytype
1445 = build_function_type (TREE_TYPE (oldtype),
1446 TYPE_ARG_TYPES (newtype));
1447 trytype = build_type_attribute_variant (trytype,
1448 TYPE_ATTRIBUTES (oldtype));
1449
1450 oldtype = trytype;
1451 if (! different_binding_level)
1452 TREE_TYPE (olddecl) = oldtype;
1453 }
1454 if (!types_match)
1455 {
1456 /* If types don't match for a built-in, throw away the built-in. */
1457 warning_with_decl (newdecl, "conflicting types for built-in function `%s'");
1458 return 0;
1459 }
1460 }
1461 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1462 && DECL_SOURCE_LINE (olddecl) == 0)
1463 {
1464 /* A function declaration for a predeclared function
1465 that isn't actually built in. */
1466 if (!TREE_PUBLIC (newdecl))
1467 {
1468 /* If you declare it as static, the
1469 default definition is overridden. */
1470 return 0;
1471 }
1472 else if (!types_match)
1473 {
1474 /* If the types don't match, preserve volatility indication.
1475 Later on, we will discard everything else about the
1476 default declaration. */
1477 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1478 }
1479 }
1480 /* Permit char *foo () to match void *foo (...) if not pedantic,
1481 if one of them came from a system header file. */
1482 else if (!types_match
1483 && TREE_CODE (olddecl) == FUNCTION_DECL
1484 && TREE_CODE (newdecl) == FUNCTION_DECL
1485 && TREE_CODE (TREE_TYPE (oldtype)) == POINTER_TYPE
1486 && TREE_CODE (TREE_TYPE (newtype)) == POINTER_TYPE
1487 && (DECL_IN_SYSTEM_HEADER (olddecl)
1488 || DECL_IN_SYSTEM_HEADER (newdecl))
1489 && ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (newtype))) == void_type_node
1490 && TYPE_ARG_TYPES (oldtype) == 0
1491 && self_promoting_args_p (TYPE_ARG_TYPES (newtype))
1492 && TREE_TYPE (TREE_TYPE (oldtype)) == char_type_node)
1493 ||
1494 (TREE_TYPE (TREE_TYPE (newtype)) == char_type_node
1495 && TYPE_ARG_TYPES (newtype) == 0
1496 && self_promoting_args_p (TYPE_ARG_TYPES (oldtype))
1497 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)))
1498 {
1499 if (pedantic)
1500 pedwarn_with_decl (newdecl, "conflicting types for `%s'");
1501 /* Make sure we keep void * as ret type, not char *. */
1502 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)
1503 TREE_TYPE (newdecl) = newtype = oldtype;
1504
1505 /* Set DECL_IN_SYSTEM_HEADER, so that if we see another declaration
1506 we will come back here again. */
1507 DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1508 }
1509 else if (!types_match
1510 /* Permit char *foo (int, ...); followed by char *foo ();
1511 if not pedantic. */
1512 && ! (TREE_CODE (olddecl) == FUNCTION_DECL
1513 && ! pedantic
1514 /* Return types must still match. */
1515 && comptypes (TREE_TYPE (oldtype),
1516 TREE_TYPE (newtype))
1517 && TYPE_ARG_TYPES (newtype) == 0))
1518 {
1519 error_with_decl (newdecl, "conflicting types for `%s'");
1520 /* Check for function type mismatch
1521 involving an empty arglist vs a nonempty one. */
1522 if (TREE_CODE (olddecl) == FUNCTION_DECL
1523 && comptypes (TREE_TYPE (oldtype),
1524 TREE_TYPE (newtype))
1525 && ((TYPE_ARG_TYPES (oldtype) == 0
1526 && DECL_INITIAL (olddecl) == 0)
1527 ||
1528 (TYPE_ARG_TYPES (newtype) == 0
1529 && DECL_INITIAL (newdecl) == 0)))
1530 {
1531 /* Classify the problem further. */
1532 tree t = TYPE_ARG_TYPES (oldtype);
1533 if (t == 0)
1534 t = TYPE_ARG_TYPES (newtype);
1535 for (; t; t = TREE_CHAIN (t))
1536 {
1537 tree type = TREE_VALUE (t);
1538
1539 if (TREE_CHAIN (t) == 0
1540 && TYPE_MAIN_VARIANT (type) != void_type_node)
1541 {
1542 error ("a parameter list with an ellipsis can't match an empty parameter name list declaration");
1543 break;
1544 }
1545
1546 if (c_type_promotes_to (type) != type)
1547 {
1548 error ("an argument type that has a default promotion can't match an empty parameter name list declaration");
1549 break;
1550 }
1551 }
1552 }
1553 error_with_decl (olddecl, "previous declaration of `%s'");
1554 }
1555 else
1556 {
1557 errmsg = redeclaration_error_message (newdecl, olddecl);
1558 if (errmsg)
1559 {
1560 switch (errmsg)
1561 {
1562 case 1:
1563 error_with_decl (newdecl, "redefinition of `%s'");
1564 break;
1565 case 2:
1566 error_with_decl (newdecl, "redeclaration of `%s'");
1567 break;
1568 case 3:
1569 error_with_decl (newdecl, "conflicting declarations of `%s'");
1570 break;
1571 default:
1572 abort ();
1573 }
1574
1575 error_with_decl (olddecl,
1576 ((DECL_INITIAL (olddecl)
1577 && current_binding_level == global_binding_level)
1578 ? "`%s' previously defined here"
1579 : "`%s' previously declared here"));
1580 return 0;
1581 }
1582 else if (TREE_CODE (newdecl) == TYPE_DECL
1583 && (DECL_IN_SYSTEM_HEADER (olddecl)
1584 || DECL_IN_SYSTEM_HEADER (newdecl)))
1585 {
1586 warning_with_decl (newdecl, "redefinition of `%s'");
1587 warning_with_decl
1588 (olddecl,
1589 ((DECL_INITIAL (olddecl)
1590 && current_binding_level == global_binding_level)
1591 ? "`%s' previously defined here"
1592 : "`%s' previously declared here"));
1593 }
1594 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1595 && DECL_INITIAL (olddecl) != 0
1596 && TYPE_ARG_TYPES (oldtype) == 0
1597 && TYPE_ARG_TYPES (newtype) != 0
1598 && TYPE_ACTUAL_ARG_TYPES (oldtype) != 0)
1599 {
1600 tree type, parm;
1601 int nargs;
1602 /* Prototype decl follows defn w/o prototype. */
1603
1604 for (parm = TYPE_ACTUAL_ARG_TYPES (oldtype),
1605 type = TYPE_ARG_TYPES (newtype),
1606 nargs = 1;
1607 ;
1608 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type), nargs++)
1609 {
1610 if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
1611 && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
1612 {
1613 warning_with_decl (newdecl, "prototype for `%s' follows");
1614 warning_with_decl (olddecl, "non-prototype definition here");
1615 break;
1616 }
1617 if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
1618 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
1619 {
1620 error_with_decl (newdecl,
1621 "prototype for `%s' follows and number of arguments doesn't match");
1622 error_with_decl (olddecl, "non-prototype definition here");
1623 errmsg = 1;
1624 break;
1625 }
1626 /* Type for passing arg must be consistent
1627 with that declared for the arg. */
1628 if (! comptypes (TREE_VALUE (parm), TREE_VALUE (type)))
1629 {
1630 error_with_decl (newdecl,
1631 "prototype for `%s' follows and argument %d doesn't match",
1632 nargs);
1633 error_with_decl (olddecl, "non-prototype definition here");
1634 errmsg = 1;
1635 break;
1636 }
1637 }
1638 }
1639 /* Warn about mismatches in various flags. */
1640 else
1641 {
1642 /* Warn if function is now inline
1643 but was previously declared not inline and has been called. */
1644 if (TREE_CODE (olddecl) == FUNCTION_DECL
1645 && ! DECL_DECLARED_INLINE_P (olddecl)
1646 && DECL_DECLARED_INLINE_P (newdecl)
1647 && TREE_USED (olddecl))
1648 warning_with_decl (newdecl,
1649 "`%s' declared inline after being called");
1650 if (TREE_CODE (olddecl) == FUNCTION_DECL
1651 && ! DECL_DECLARED_INLINE_P (olddecl)
1652 && DECL_DECLARED_INLINE_P (newdecl)
1653 && DECL_INITIAL (olddecl) != 0)
1654 warning_with_decl (newdecl,
1655 "`%s' declared inline after its definition");
1656
1657 /* If pedantic, warn when static declaration follows a non-static
1658 declaration. Otherwise, do so only for functions. */
1659 if ((pedantic || TREE_CODE (olddecl) == FUNCTION_DECL)
1660 && TREE_PUBLIC (olddecl)
1661 && !TREE_PUBLIC (newdecl))
1662 warning_with_decl (newdecl, "static declaration for `%s' follows non-static");
1663
1664 /* If warn_traditional, warn when a non-static function
1665 declaration follows a static one. */
1666 if (warn_traditional && !in_system_header
1667 && TREE_CODE (olddecl) == FUNCTION_DECL
1668 && !TREE_PUBLIC (olddecl)
1669 && TREE_PUBLIC (newdecl))
1670 warning_with_decl (newdecl, "non-static declaration for `%s' follows static");
1671
1672 /* Warn when const declaration follows a non-const
1673 declaration, but not for functions. */
1674 if (TREE_CODE (olddecl) != FUNCTION_DECL
1675 && !TREE_READONLY (olddecl)
1676 && TREE_READONLY (newdecl))
1677 warning_with_decl (newdecl, "const declaration for `%s' follows non-const");
1678 /* These bits are logically part of the type, for variables.
1679 But not for functions
1680 (where qualifiers are not valid ANSI anyway). */
1681 else if (pedantic && TREE_CODE (olddecl) != FUNCTION_DECL
1682 && (TREE_READONLY (newdecl) != TREE_READONLY (olddecl)
1683 || TREE_THIS_VOLATILE (newdecl) != TREE_THIS_VOLATILE (olddecl)))
1684 pedwarn_with_decl (newdecl, "type qualifiers for `%s' conflict with previous decl");
1685 }
1686 }
1687
1688 /* Optionally warn about more than one declaration for the same name. */
1689 if (errmsg == 0 && warn_redundant_decls && DECL_SOURCE_LINE (olddecl) != 0
1690 /* Don't warn about a function declaration
1691 followed by a definition. */
1692 && !(TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl) != 0
1693 && DECL_INITIAL (olddecl) == 0)
1694 /* Don't warn about extern decl followed by (tentative) definition. */
1695 && !(DECL_EXTERNAL (olddecl) && ! DECL_EXTERNAL (newdecl)))
1696 {
1697 warning_with_decl (newdecl, "redundant redeclaration of `%s' in same scope");
1698 warning_with_decl (olddecl, "previous declaration of `%s'");
1699 }
1700
1701 /* Copy all the DECL_... slots specified in the new decl
1702 except for any that we copy here from the old type.
1703
1704 Past this point, we don't change OLDTYPE and NEWTYPE
1705 even if we change the types of NEWDECL and OLDDECL. */
1706
1707 if (types_match)
1708 {
1709 /* When copying info to olddecl, we store into write_olddecl
1710 instead. This allows us to avoid modifying olddecl when
1711 different_binding_level is true. */
1712 tree write_olddecl = different_binding_level ? newdecl : olddecl;
1713
1714 /* Merge the data types specified in the two decls. */
1715 if (TREE_CODE (newdecl) != FUNCTION_DECL || !DECL_BUILT_IN (olddecl))
1716 {
1717 if (different_binding_level)
1718 {
1719 if (TYPE_ARG_TYPES (oldtype) != 0
1720 && TYPE_ARG_TYPES (newtype) == 0)
1721 TREE_TYPE (newdecl) = common_type (newtype, oldtype);
1722 else
1723 TREE_TYPE (newdecl)
1724 = build_type_attribute_variant
1725 (newtype,
1726 merge_attributes (TYPE_ATTRIBUTES (newtype),
1727 TYPE_ATTRIBUTES (oldtype)));
1728 }
1729 else
1730 TREE_TYPE (newdecl)
1731 = TREE_TYPE (olddecl)
1732 = common_type (newtype, oldtype);
1733 }
1734
1735 /* Lay the type out, unless already done. */
1736 if (oldtype != TREE_TYPE (newdecl))
1737 {
1738 if (TREE_TYPE (newdecl) != error_mark_node)
1739 layout_type (TREE_TYPE (newdecl));
1740 if (TREE_CODE (newdecl) != FUNCTION_DECL
1741 && TREE_CODE (newdecl) != TYPE_DECL
1742 && TREE_CODE (newdecl) != CONST_DECL)
1743 layout_decl (newdecl, 0);
1744 }
1745 else
1746 {
1747 /* Since the type is OLDDECL's, make OLDDECL's size go with. */
1748 DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
1749 DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
1750 DECL_MODE (newdecl) = DECL_MODE (olddecl);
1751 if (TREE_CODE (olddecl) != FUNCTION_DECL)
1752 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
1753 {
1754 DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
1755 DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
1756 }
1757 }
1758
1759 /* Keep the old rtl since we can safely use it. */
1760 COPY_DECL_RTL (olddecl, newdecl);
1761
1762 /* Merge the type qualifiers. */
1763 if (TREE_CODE (olddecl) == FUNCTION_DECL
1764 && DECL_BUILT_IN_NONANSI (olddecl) && TREE_THIS_VOLATILE (olddecl)
1765 && ! TREE_THIS_VOLATILE (newdecl))
1766 TREE_THIS_VOLATILE (write_olddecl) = 0;
1767
1768 if (TREE_READONLY (newdecl))
1769 TREE_READONLY (write_olddecl) = 1;
1770
1771 if (TREE_THIS_VOLATILE (newdecl))
1772 {
1773 TREE_THIS_VOLATILE (write_olddecl) = 1;
1774 if (TREE_CODE (newdecl) == VAR_DECL
1775 /* If an automatic variable is re-declared in the same
1776 function scope, but the old declaration was not
1777 volatile, make_var_volatile() would crash because the
1778 variable would have been assigned to a pseudo, not a
1779 MEM. Since this duplicate declaration is invalid
1780 anyway, we just skip the call. */
1781 && errmsg == 0)
1782 make_var_volatile (newdecl);
1783 }
1784
1785 /* Keep source location of definition rather than declaration. */
1786 /* When called with different_binding_level set, keep the old
1787 information so that meaningful diagnostics can be given. */
1788 if (DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0
1789 && ! different_binding_level)
1790 {
1791 DECL_SOURCE_LINE (newdecl) = DECL_SOURCE_LINE (olddecl);
1792 DECL_SOURCE_FILE (newdecl) = DECL_SOURCE_FILE (olddecl);
1793 }
1794
1795 /* Merge the unused-warning information. */
1796 if (DECL_IN_SYSTEM_HEADER (olddecl))
1797 DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1798 else if (DECL_IN_SYSTEM_HEADER (newdecl))
1799 DECL_IN_SYSTEM_HEADER (write_olddecl) = 1;
1800
1801 /* Merge the initialization information. */
1802 /* When called with different_binding_level set, don't copy over
1803 DECL_INITIAL, so that we don't accidentally change function
1804 declarations into function definitions. */
1805 if (DECL_INITIAL (newdecl) == 0 && ! different_binding_level)
1806 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1807
1808 /* Merge the section attribute.
1809 We want to issue an error if the sections conflict but that must be
1810 done later in decl_attributes since we are called before attributes
1811 are assigned. */
1812 if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
1813 DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
1814
1815 /* Copy the assembler name.
1816 Currently, it can only be defined in the prototype. */
1817 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
1818
1819 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1820 {
1821 DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
1822 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1823 DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
1824 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
1825 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
1826 }
1827 }
1828 /* If cannot merge, then use the new type and qualifiers,
1829 and don't preserve the old rtl. */
1830 else if (! different_binding_level)
1831 {
1832 TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
1833 TREE_READONLY (olddecl) = TREE_READONLY (newdecl);
1834 TREE_THIS_VOLATILE (olddecl) = TREE_THIS_VOLATILE (newdecl);
1835 TREE_SIDE_EFFECTS (olddecl) = TREE_SIDE_EFFECTS (newdecl);
1836 }
1837
1838 /* Merge the storage class information. */
1839 merge_weak (newdecl, olddecl);
1840
1841 /* For functions, static overrides non-static. */
1842 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1843 {
1844 TREE_PUBLIC (newdecl) &= TREE_PUBLIC (olddecl);
1845 /* This is since we don't automatically
1846 copy the attributes of NEWDECL into OLDDECL. */
1847 /* No need to worry about different_binding_level here because
1848 then TREE_PUBLIC (newdecl) was true. */
1849 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1850 /* If this clears `static', clear it in the identifier too. */
1851 if (! TREE_PUBLIC (olddecl))
1852 TREE_PUBLIC (DECL_NAME (olddecl)) = 0;
1853 }
1854 if (DECL_EXTERNAL (newdecl))
1855 {
1856 if (! different_binding_level)
1857 {
1858 /* Don't mess with these flags on local externs; they remain
1859 external even if there's a declaration at file scope which
1860 isn't. */
1861 TREE_STATIC (newdecl) = TREE_STATIC (olddecl);
1862 DECL_EXTERNAL (newdecl) = DECL_EXTERNAL (olddecl);
1863 }
1864 /* An extern decl does not override previous storage class. */
1865 TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
1866 if (! DECL_EXTERNAL (newdecl))
1867 DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
1868 }
1869 else
1870 {
1871 TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
1872 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1873 }
1874
1875 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1876 {
1877 /* If we're redefining a function previously defined as extern
1878 inline, make sure we emit debug info for the inline before we
1879 throw it away, in case it was inlined into a function that hasn't
1880 been written out yet. */
1881 if (new_is_definition && DECL_INITIAL (olddecl) && TREE_USED (olddecl))
1882 {
1883 (*debug_hooks->outlining_inline_function) (olddecl);
1884
1885 /* The new defn must not be inline. */
1886 DECL_INLINE (newdecl) = 0;
1887 DECL_UNINLINABLE (newdecl) = 1;
1888 }
1889 else
1890 {
1891 /* If either decl says `inline', this fn is inline,
1892 unless its definition was passed already. */
1893 if (DECL_DECLARED_INLINE_P (newdecl)
1894 || DECL_DECLARED_INLINE_P (olddecl))
1895 DECL_DECLARED_INLINE_P (newdecl) = 1;
1896
1897 DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
1898 = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
1899 }
1900
1901 if (DECL_BUILT_IN (olddecl))
1902 {
1903 /* Get rid of any built-in function if new arg types don't match it
1904 or if we have a function definition. */
1905 if (! types_match || new_is_definition)
1906 {
1907 if (! different_binding_level)
1908 {
1909 TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
1910 DECL_BUILT_IN_CLASS (olddecl) = NOT_BUILT_IN;
1911 }
1912 }
1913 else
1914 {
1915 /* If redeclaring a builtin function, and not a definition,
1916 it stays built in. */
1917 DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
1918 DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
1919 }
1920 }
1921
1922 /* Also preserve various other info from the definition. */
1923 if (! new_is_definition)
1924 {
1925 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
1926 /* When called with different_binding_level set, don't copy over
1927 DECL_INITIAL, so that we don't accidentally change function
1928 declarations into function definitions. */
1929 if (! different_binding_level)
1930 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1931 DECL_SAVED_INSNS (newdecl) = DECL_SAVED_INSNS (olddecl);
1932 DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
1933 DECL_NUM_STMTS (newdecl) = DECL_NUM_STMTS (olddecl);
1934 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
1935
1936 /* Set DECL_INLINE on the declaration if we've got a body
1937 from which to instantiate. */
1938 if (DECL_INLINE (olddecl) && ! DECL_UNINLINABLE (newdecl))
1939 {
1940 DECL_INLINE (newdecl) = 1;
1941 DECL_ABSTRACT_ORIGIN (newdecl)
1942 = (different_binding_level
1943 ? DECL_ORIGIN (olddecl)
1944 : DECL_ABSTRACT_ORIGIN (olddecl));
1945 }
1946 }
1947 else
1948 {
1949 /* If a previous declaration said inline, mark the
1950 definition as inlinable. */
1951 if (DECL_DECLARED_INLINE_P (newdecl)
1952 && ! DECL_UNINLINABLE (newdecl))
1953 DECL_INLINE (newdecl) = 1;
1954 }
1955 }
1956 if (different_binding_level)
1957 return 0;
1958
1959 /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
1960 But preserve OLDDECL's DECL_UID. */
1961 {
1962 unsigned olddecl_uid = DECL_UID (olddecl);
1963
1964 memcpy ((char *) olddecl + sizeof (struct tree_common),
1965 (char *) newdecl + sizeof (struct tree_common),
1966 sizeof (struct tree_decl) - sizeof (struct tree_common));
1967 DECL_UID (olddecl) = olddecl_uid;
1968 }
1969
1970 /* NEWDECL contains the merged attribute lists.
1971 Update OLDDECL to be the same. */
1972 DECL_ATTRIBUTES (olddecl) = DECL_ATTRIBUTES (newdecl);
1973
1974 return 1;
1975 }
1976
1977 /* Check whether decl-node X shadows an existing declaration.
1978 OLDLOCAL is the old IDENTIFIER_LOCAL_VALUE of the DECL_NAME of X,
1979 which might be a NULL_TREE. */
1980 static void
1981 warn_if_shadowing (x, oldlocal)
1982 tree x, oldlocal;
1983 {
1984 tree name;
1985
1986 if (DECL_EXTERNAL (x))
1987 return;
1988
1989 name = DECL_NAME (x);
1990
1991 /* Warn if shadowing an argument at the top level of the body. */
1992 if (oldlocal != 0
1993 /* This warning doesn't apply to the parms of a nested fcn. */
1994 && ! current_binding_level->parm_flag
1995 /* Check that this is one level down from the parms. */
1996 && current_binding_level->level_chain->parm_flag
1997 /* Check that the decl being shadowed
1998 comes from the parm level, one level up. */
1999 && chain_member (oldlocal, current_binding_level->level_chain->names))
2000 {
2001 if (TREE_CODE (oldlocal) == PARM_DECL)
2002 pedwarn ("declaration of `%s' shadows a parameter",
2003 IDENTIFIER_POINTER (name));
2004 else
2005 pedwarn ("declaration of `%s' shadows a symbol from the parameter list",
2006 IDENTIFIER_POINTER (name));
2007 }
2008 /* Maybe warn if shadowing something else. */
2009 else if (warn_shadow
2010 /* No shadow warnings for internally generated vars. */
2011 && DECL_SOURCE_LINE (x) != 0
2012 /* No shadow warnings for vars made for inlining. */
2013 && ! DECL_FROM_INLINE (x))
2014 {
2015 if (TREE_CODE (x) == PARM_DECL
2016 && current_binding_level->level_chain->parm_flag)
2017 /* Don't warn about the parm names in function declarator
2018 within a function declarator.
2019 It would be nice to avoid warning in any function
2020 declarator in a declaration, as opposed to a definition,
2021 but there is no way to tell it's not a definition. */
2022 ;
2023 else if (oldlocal)
2024 {
2025 if (TREE_CODE (oldlocal) == PARM_DECL)
2026 shadow_warning ("a parameter", name, oldlocal);
2027 else
2028 shadow_warning ("a previous local", name, oldlocal);
2029 }
2030 else if (IDENTIFIER_GLOBAL_VALUE (name) != 0
2031 && IDENTIFIER_GLOBAL_VALUE (name) != error_mark_node)
2032 shadow_warning ("a global declaration", name,
2033 IDENTIFIER_GLOBAL_VALUE (name));
2034 }
2035 }
2036
2037 /* Record a decl-node X as belonging to the current lexical scope.
2038 Check for errors (such as an incompatible declaration for the same
2039 name already seen in the same scope).
2040
2041 Returns either X or an old decl for the same name.
2042 If an old decl is returned, it may have been smashed
2043 to agree with what X says. */
2044
2045 tree
2046 pushdecl (x)
2047 tree x;
2048 {
2049 tree t;
2050 tree name = DECL_NAME (x);
2051 struct binding_level *b = current_binding_level;
2052
2053 /* Functions need the lang_decl data. */
2054 if (TREE_CODE (x) == FUNCTION_DECL && ! DECL_LANG_SPECIFIC (x))
2055 DECL_LANG_SPECIFIC (x) = (struct lang_decl *)
2056 ggc_alloc_cleared (sizeof (struct lang_decl));
2057
2058 DECL_CONTEXT (x) = current_function_decl;
2059 /* A local extern declaration for a function doesn't constitute nesting.
2060 A local auto declaration does, since it's a forward decl
2061 for a nested function coming later. */
2062 if ((TREE_CODE (x) == FUNCTION_DECL || TREE_CODE (x) == VAR_DECL)
2063 && DECL_INITIAL (x) == 0 && DECL_EXTERNAL (x))
2064 DECL_CONTEXT (x) = 0;
2065
2066 if (name)
2067 {
2068 int different_binding_level = 0;
2069
2070 if (warn_nested_externs
2071 && DECL_EXTERNAL (x)
2072 && b != global_binding_level
2073 && x != IDENTIFIER_IMPLICIT_DECL (name)
2074 /* No error messages for __FUNCTION__ and __PRETTY_FUNCTION__. */
2075 && !DECL_IN_SYSTEM_HEADER (x))
2076 warning ("nested extern declaration of `%s'",
2077 IDENTIFIER_POINTER (name));
2078
2079 t = lookup_name_current_level (name);
2080 if (! t && DECL_EXTERNAL (x) && TREE_PUBLIC (x))
2081 {
2082 t = IDENTIFIER_GLOBAL_VALUE (name);
2083 /* Type decls at global scope don't conflict with externs declared
2084 inside lexical blocks. */
2085 if (! t || TREE_CODE (t) == TYPE_DECL)
2086 /* If there's no visible global declaration, try for an
2087 invisible one. */
2088 t = IDENTIFIER_LIMBO_VALUE (name);
2089 different_binding_level = 1;
2090 }
2091 if (t != 0 && t == error_mark_node)
2092 /* error_mark_node is 0 for a while during initialization! */
2093 {
2094 t = 0;
2095 error_with_decl (x, "`%s' used prior to declaration");
2096 }
2097
2098 /* If this decl is `static' and an implicit decl was seen previously,
2099 warn. */
2100 if (TREE_PUBLIC (name)
2101 /* Don't test for DECL_EXTERNAL, because grokdeclarator
2102 sets this for all functions. */
2103 && ! TREE_PUBLIC (x)
2104 && (TREE_CODE (x) == FUNCTION_DECL || b == global_binding_level)
2105 /* We used to warn also for explicit extern followed by static,
2106 but sometimes you need to do it that way. */
2107 && IDENTIFIER_IMPLICIT_DECL (name) != 0)
2108 {
2109 pedwarn ("`%s' was declared implicitly `extern' and later `static'",
2110 IDENTIFIER_POINTER (name));
2111 pedwarn_with_file_and_line
2112 (DECL_SOURCE_FILE (IDENTIFIER_IMPLICIT_DECL (name)),
2113 DECL_SOURCE_LINE (IDENTIFIER_IMPLICIT_DECL (name)),
2114 "previous declaration of `%s'",
2115 IDENTIFIER_POINTER (name));
2116 TREE_THIS_VOLATILE (name) = 1;
2117 }
2118
2119 if (t != 0 && duplicate_decls (x, t, different_binding_level))
2120 {
2121 if (TREE_CODE (t) == PARM_DECL)
2122 {
2123 /* Don't allow more than one "real" duplicate
2124 of a forward parm decl. */
2125 TREE_ASM_WRITTEN (t) = TREE_ASM_WRITTEN (x);
2126 return t;
2127 }
2128 return t;
2129 }
2130
2131 /* If we are processing a typedef statement, generate a whole new
2132 ..._TYPE node (which will be just an variant of the existing
2133 ..._TYPE node with identical properties) and then install the
2134 TYPE_DECL node generated to represent the typedef name as the
2135 TYPE_NAME of this brand new (duplicate) ..._TYPE node.
2136
2137 The whole point here is to end up with a situation where each
2138 and every ..._TYPE node the compiler creates will be uniquely
2139 associated with AT MOST one node representing a typedef name.
2140 This way, even though the compiler substitutes corresponding
2141 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
2142 early on, later parts of the compiler can always do the reverse
2143 translation and get back the corresponding typedef name. For
2144 example, given:
2145
2146 typedef struct S MY_TYPE;
2147 MY_TYPE object;
2148
2149 Later parts of the compiler might only know that `object' was of
2150 type `struct S' if it were not for code just below. With this
2151 code however, later parts of the compiler see something like:
2152
2153 struct S' == struct S
2154 typedef struct S' MY_TYPE;
2155 struct S' object;
2156
2157 And they can then deduce (from the node for type struct S') that
2158 the original object declaration was:
2159
2160 MY_TYPE object;
2161
2162 Being able to do this is important for proper support of protoize,
2163 and also for generating precise symbolic debugging information
2164 which takes full account of the programmer's (typedef) vocabulary.
2165
2166 Obviously, we don't want to generate a duplicate ..._TYPE node if
2167 the TYPE_DECL node that we are now processing really represents a
2168 standard built-in type.
2169
2170 Since all standard types are effectively declared at line zero
2171 in the source file, we can easily check to see if we are working
2172 on a standard type by checking the current value of lineno. */
2173
2174 if (TREE_CODE (x) == TYPE_DECL)
2175 {
2176 if (DECL_SOURCE_LINE (x) == 0)
2177 {
2178 if (TYPE_NAME (TREE_TYPE (x)) == 0)
2179 TYPE_NAME (TREE_TYPE (x)) = x;
2180 }
2181 else if (TREE_TYPE (x) != error_mark_node
2182 && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
2183 {
2184 tree tt = TREE_TYPE (x);
2185 DECL_ORIGINAL_TYPE (x) = tt;
2186 tt = build_type_copy (tt);
2187 TYPE_NAME (tt) = x;
2188 TREE_USED (tt) = TREE_USED (x);
2189 TREE_TYPE (x) = tt;
2190 }
2191 }
2192
2193 /* Multiple external decls of the same identifier ought to match.
2194 We get warnings about inline functions where they are defined.
2195 Avoid duplicate warnings where they are used. */
2196 if (TREE_PUBLIC (x)
2197 && ! (TREE_CODE (x) == FUNCTION_DECL && DECL_INLINE (x)))
2198 {
2199 tree decl;
2200
2201 if (IDENTIFIER_LIMBO_VALUE (name) != 0)
2202 /* Decls in limbo are always extern, so no need to check that. */
2203 decl = IDENTIFIER_LIMBO_VALUE (name);
2204 else
2205 decl = 0;
2206
2207 if (decl && ! comptypes (TREE_TYPE (x), TREE_TYPE (decl))
2208 /* If old decl is built-in, we already warned if we should. */
2209 && !DECL_BUILT_IN (decl))
2210 {
2211 pedwarn_with_decl (x,
2212 "type mismatch with previous external decl");
2213 pedwarn_with_decl (decl, "previous external decl of `%s'");
2214 }
2215 }
2216
2217 /* If a function has had an implicit declaration, and then is defined,
2218 make sure they are compatible. */
2219
2220 if (IDENTIFIER_IMPLICIT_DECL (name) != 0
2221 && IDENTIFIER_GLOBAL_VALUE (name) == 0
2222 && TREE_CODE (x) == FUNCTION_DECL
2223 && ! comptypes (TREE_TYPE (x),
2224 TREE_TYPE (IDENTIFIER_IMPLICIT_DECL (name))))
2225 {
2226 warning_with_decl (x, "type mismatch with previous implicit declaration");
2227 warning_with_decl (IDENTIFIER_IMPLICIT_DECL (name),
2228 "previous implicit declaration of `%s'");
2229 }
2230
2231 /* This name is new in its binding level.
2232 Install the new declaration and return it. */
2233 if (b == global_binding_level)
2234 {
2235 /* Install a global value. */
2236
2237 /* If the first global decl has external linkage,
2238 warn if we later see static one. */
2239 if (IDENTIFIER_GLOBAL_VALUE (name) == 0 && TREE_PUBLIC (x))
2240 TREE_PUBLIC (name) = 1;
2241
2242 IDENTIFIER_GLOBAL_VALUE (name) = x;
2243
2244 /* We no longer care about any previous block level declarations. */
2245 IDENTIFIER_LIMBO_VALUE (name) = 0;
2246
2247 /* Don't forget if the function was used via an implicit decl. */
2248 if (IDENTIFIER_IMPLICIT_DECL (name)
2249 && TREE_USED (IDENTIFIER_IMPLICIT_DECL (name)))
2250 TREE_USED (x) = 1, TREE_USED (name) = 1;
2251
2252 /* Don't forget if its address was taken in that way. */
2253 if (IDENTIFIER_IMPLICIT_DECL (name)
2254 && TREE_ADDRESSABLE (IDENTIFIER_IMPLICIT_DECL (name)))
2255 TREE_ADDRESSABLE (x) = 1;
2256
2257 /* Warn about mismatches against previous implicit decl. */
2258 if (IDENTIFIER_IMPLICIT_DECL (name) != 0
2259 /* If this real decl matches the implicit, don't complain. */
2260 && ! (TREE_CODE (x) == FUNCTION_DECL
2261 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (x)))
2262 == integer_type_node)))
2263 pedwarn ("`%s' was previously implicitly declared to return `int'",
2264 IDENTIFIER_POINTER (name));
2265
2266 /* If this decl is `static' and an `extern' was seen previously,
2267 that is erroneous. */
2268 if (TREE_PUBLIC (name)
2269 && ! TREE_PUBLIC (x) && ! DECL_EXTERNAL (x))
2270 {
2271 /* Okay to redeclare an ANSI built-in as static. */
2272 if (t != 0 && DECL_BUILT_IN (t))
2273 ;
2274 /* Okay to declare a non-ANSI built-in as anything. */
2275 else if (t != 0 && DECL_BUILT_IN_NONANSI (t))
2276 ;
2277 /* Okay to have global type decl after an earlier extern
2278 declaration inside a lexical block. */
2279 else if (TREE_CODE (x) == TYPE_DECL)
2280 ;
2281 else if (IDENTIFIER_IMPLICIT_DECL (name))
2282 {
2283 if (! TREE_THIS_VOLATILE (name))
2284 pedwarn ("`%s' was declared implicitly `extern' and later `static'",
2285 IDENTIFIER_POINTER (name));
2286 }
2287 else
2288 pedwarn ("`%s' was declared `extern' and later `static'",
2289 IDENTIFIER_POINTER (name));
2290 }
2291 }
2292 else
2293 {
2294 /* Here to install a non-global value. */
2295 tree oldlocal = IDENTIFIER_LOCAL_VALUE (name);
2296 tree oldglobal = IDENTIFIER_GLOBAL_VALUE (name);
2297
2298 IDENTIFIER_LOCAL_VALUE (name) = x;
2299
2300 /* If this is an extern function declaration, see if we
2301 have a global definition or declaration for the function. */
2302 if (oldlocal == 0
2303 && oldglobal != 0
2304 && TREE_CODE (x) == FUNCTION_DECL
2305 && TREE_CODE (oldglobal) == FUNCTION_DECL
2306 && DECL_EXTERNAL (x)
2307 && ! DECL_DECLARED_INLINE_P (x))
2308 {
2309 /* We have one. Their types must agree. */
2310 if (! comptypes (TREE_TYPE (x),
2311 TREE_TYPE (IDENTIFIER_GLOBAL_VALUE (name))))
2312 pedwarn_with_decl (x, "extern declaration of `%s' doesn't match global one");
2313 else
2314 {
2315 /* Inner extern decl is inline if global one is.
2316 Copy enough to really inline it. */
2317 if (DECL_DECLARED_INLINE_P (oldglobal))
2318 {
2319 DECL_DECLARED_INLINE_P (x)
2320 = DECL_DECLARED_INLINE_P (oldglobal);
2321 DECL_INLINE (x) = DECL_INLINE (oldglobal);
2322 DECL_INITIAL (x) = (current_function_decl == oldglobal
2323 ? 0 : DECL_INITIAL (oldglobal));
2324 DECL_SAVED_INSNS (x) = DECL_SAVED_INSNS (oldglobal);
2325 DECL_NUM_STMTS (x) = DECL_NUM_STMTS (oldglobal);
2326 DECL_ARGUMENTS (x) = DECL_ARGUMENTS (oldglobal);
2327 DECL_RESULT (x) = DECL_RESULT (oldglobal);
2328 TREE_ASM_WRITTEN (x) = TREE_ASM_WRITTEN (oldglobal);
2329 DECL_ABSTRACT_ORIGIN (x)
2330 = DECL_ABSTRACT_ORIGIN (oldglobal);
2331 }
2332 /* Inner extern decl is built-in if global one is. */
2333 if (DECL_BUILT_IN (oldglobal))
2334 {
2335 DECL_BUILT_IN_CLASS (x) = DECL_BUILT_IN_CLASS (oldglobal);
2336 DECL_FUNCTION_CODE (x) = DECL_FUNCTION_CODE (oldglobal);
2337 }
2338 /* Keep the arg types from a file-scope fcn defn. */
2339 if (TYPE_ARG_TYPES (TREE_TYPE (oldglobal)) != 0
2340 && DECL_INITIAL (oldglobal)
2341 && TYPE_ARG_TYPES (TREE_TYPE (x)) == 0)
2342 TREE_TYPE (x) = TREE_TYPE (oldglobal);
2343 }
2344 }
2345
2346 #if 0
2347 /* This case is probably sometimes the right thing to do. */
2348 /* If we have a local external declaration,
2349 then any file-scope declaration should not
2350 have been static. */
2351 if (oldlocal == 0 && oldglobal != 0
2352 && !TREE_PUBLIC (oldglobal)
2353 && DECL_EXTERNAL (x) && TREE_PUBLIC (x))
2354 warning ("`%s' locally external but globally static",
2355 IDENTIFIER_POINTER (name));
2356 #endif
2357
2358 /* If we have a local external declaration,
2359 and no file-scope declaration has yet been seen,
2360 then if we later have a file-scope decl it must not be static. */
2361 if (oldlocal == 0
2362 && DECL_EXTERNAL (x)
2363 && TREE_PUBLIC (x))
2364 {
2365 if (oldglobal == 0)
2366 TREE_PUBLIC (name) = 1;
2367
2368 /* Save this decl, so that we can do type checking against
2369 other decls after it falls out of scope.
2370
2371 Only save it once. This prevents temporary decls created in
2372 expand_inline_function from being used here, since this
2373 will have been set when the inline function was parsed.
2374 It also helps give slightly better warnings. */
2375 if (IDENTIFIER_LIMBO_VALUE (name) == 0)
2376 IDENTIFIER_LIMBO_VALUE (name) = x;
2377 }
2378
2379 warn_if_shadowing (x, oldlocal);
2380
2381 /* If storing a local value, there may already be one (inherited).
2382 If so, record it for restoration when this binding level ends. */
2383 if (oldlocal != 0)
2384 b->shadowed = tree_cons (name, oldlocal, b->shadowed);
2385 }
2386
2387 /* Keep list of variables in this level with incomplete type.
2388 If the input is erroneous, we can have error_mark in the type
2389 slot (e.g. "f(void a, ...)") - that doesn't count as an
2390 incomplete type. */
2391 if (TREE_TYPE (x) != error_mark_node
2392 && !COMPLETE_TYPE_P (TREE_TYPE (x)))
2393 {
2394 tree element = TREE_TYPE (x);
2395
2396 while (TREE_CODE (element) == ARRAY_TYPE)
2397 element = TREE_TYPE (element);
2398 if (TREE_CODE (element) == RECORD_TYPE
2399 || TREE_CODE (element) == UNION_TYPE)
2400 b->incomplete_list = tree_cons (NULL_TREE, x, b->incomplete_list);
2401 }
2402 }
2403
2404 /* Put decls on list in reverse order.
2405 We will reverse them later if necessary. */
2406 TREE_CHAIN (x) = b->names;
2407 b->names = x;
2408
2409 return x;
2410 }
2411
2412 /* Like pushdecl, only it places X in GLOBAL_BINDING_LEVEL, if appropriate. */
2413
2414 tree
2415 pushdecl_top_level (x)
2416 tree x;
2417 {
2418 tree t;
2419 struct binding_level *b = current_binding_level;
2420
2421 current_binding_level = global_binding_level;
2422 t = pushdecl (x);
2423 current_binding_level = b;
2424 return t;
2425 }
2426 \f
2427 /* Generate an implicit declaration for identifier FUNCTIONID
2428 as a function of type int (). Print a warning if appropriate. */
2429
2430 tree
2431 implicitly_declare (functionid)
2432 tree functionid;
2433 {
2434 tree decl;
2435 int traditional_warning = 0;
2436 /* Only one "implicit declaration" warning per identifier. */
2437 int implicit_warning;
2438
2439 /* We used to reuse an old implicit decl here,
2440 but this loses with inline functions because it can clobber
2441 the saved decl chains. */
2442 #if 0
2443 if (IDENTIFIER_IMPLICIT_DECL (functionid) != 0)
2444 decl = IDENTIFIER_IMPLICIT_DECL (functionid);
2445 else
2446 #endif
2447 decl = build_decl (FUNCTION_DECL, functionid, default_function_type);
2448
2449 /* Warn of implicit decl following explicit local extern decl.
2450 This is probably a program designed for traditional C. */
2451 if (TREE_PUBLIC (functionid) && IDENTIFIER_GLOBAL_VALUE (functionid) == 0)
2452 traditional_warning = 1;
2453
2454 /* Warn once of an implicit declaration. */
2455 implicit_warning = (IDENTIFIER_IMPLICIT_DECL (functionid) == 0);
2456
2457 DECL_EXTERNAL (decl) = 1;
2458 TREE_PUBLIC (decl) = 1;
2459
2460 /* Record that we have an implicit decl and this is it. */
2461 IDENTIFIER_IMPLICIT_DECL (functionid) = decl;
2462
2463 /* ANSI standard says implicit declarations are in the innermost block.
2464 So we record the decl in the standard fashion. */
2465 pushdecl (decl);
2466
2467 /* This is a no-op in c-lang.c or something real in objc-actions.c. */
2468 maybe_objc_check_decl (decl);
2469
2470 rest_of_decl_compilation (decl, NULL, 0, 0);
2471
2472 if (implicit_warning)
2473 implicit_decl_warning (functionid);
2474 else if (warn_traditional && traditional_warning)
2475 warning ("function `%s' was previously declared within a block",
2476 IDENTIFIER_POINTER (functionid));
2477
2478 /* Write a record describing this implicit function declaration to the
2479 prototypes file (if requested). */
2480
2481 gen_aux_info_record (decl, 0, 1, 0);
2482
2483 /* Possibly apply some default attributes to this implicit declaration. */
2484 decl_attributes (&decl, NULL_TREE, 0);
2485
2486 return decl;
2487 }
2488
2489 void
2490 implicit_decl_warning (id)
2491 tree id;
2492 {
2493 const char *name = IDENTIFIER_POINTER (id);
2494 if (mesg_implicit_function_declaration == 2)
2495 error ("implicit declaration of function `%s'", name);
2496 else if (mesg_implicit_function_declaration == 1)
2497 warning ("implicit declaration of function `%s'", name);
2498 }
2499
2500 /* Return zero if the declaration NEWDECL is valid
2501 when the declaration OLDDECL (assumed to be for the same name)
2502 has already been seen.
2503 Otherwise return 1 if NEWDECL is a redefinition, 2 if it is a redeclaration,
2504 and 3 if it is a conflicting declaration. */
2505
2506 static int
2507 redeclaration_error_message (newdecl, olddecl)
2508 tree newdecl, olddecl;
2509 {
2510 if (TREE_CODE (newdecl) == TYPE_DECL)
2511 {
2512 /* Do not complain about type redeclarations where at least one
2513 declaration was in a system header. */
2514 if (DECL_IN_SYSTEM_HEADER (olddecl) || DECL_IN_SYSTEM_HEADER (newdecl))
2515 return 0;
2516 return 1;
2517 }
2518 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
2519 {
2520 /* Declarations of functions can insist on internal linkage
2521 but they can't be inconsistent with internal linkage,
2522 so there can be no error on that account.
2523 However defining the same name twice is no good. */
2524 if (DECL_INITIAL (olddecl) != 0 && DECL_INITIAL (newdecl) != 0
2525 /* However, defining once as extern inline and a second
2526 time in another way is ok. */
2527 && ! (DECL_DECLARED_INLINE_P (olddecl) && DECL_EXTERNAL (olddecl)
2528 && ! (DECL_DECLARED_INLINE_P (newdecl)
2529 && DECL_EXTERNAL (newdecl))))
2530 return 1;
2531 return 0;
2532 }
2533 else if (DECL_CONTEXT (newdecl) == NULL_TREE)
2534 {
2535 /* Objects declared at top level: */
2536 /* If at least one is a reference, it's ok. */
2537 if (DECL_EXTERNAL (newdecl) || DECL_EXTERNAL (olddecl))
2538 return 0;
2539 /* Reject two definitions. */
2540 if (DECL_INITIAL (olddecl) != 0 && DECL_INITIAL (newdecl) != 0)
2541 return 1;
2542 /* Now we have two tentative defs, or one tentative and one real def. */
2543 /* Insist that the linkage match. */
2544 if (TREE_PUBLIC (olddecl) != TREE_PUBLIC (newdecl))
2545 return 3;
2546 return 0;
2547 }
2548 else if (current_binding_level->parm_flag
2549 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
2550 return 0;
2551 else
2552 {
2553 /* Newdecl has block scope. If olddecl has block scope also, then
2554 reject two definitions, and reject a definition together with an
2555 external reference. Otherwise, it is OK, because newdecl must
2556 be an extern reference to olddecl. */
2557 if (!(DECL_EXTERNAL (newdecl) && DECL_EXTERNAL (olddecl))
2558 && DECL_CONTEXT (newdecl) == DECL_CONTEXT (olddecl))
2559 return 2;
2560 return 0;
2561 }
2562 }
2563 \f
2564 /* Get the LABEL_DECL corresponding to identifier ID as a label.
2565 Create one if none exists so far for the current function.
2566 This function is called for both label definitions and label references. */
2567
2568 tree
2569 lookup_label (id)
2570 tree id;
2571 {
2572 tree decl = IDENTIFIER_LABEL_VALUE (id);
2573
2574 if (current_function_decl == 0)
2575 {
2576 error ("label %s referenced outside of any function",
2577 IDENTIFIER_POINTER (id));
2578 return 0;
2579 }
2580
2581 /* Use a label already defined or ref'd with this name. */
2582 if (decl != 0)
2583 {
2584 /* But not if it is inherited and wasn't declared to be inheritable. */
2585 if (DECL_CONTEXT (decl) != current_function_decl
2586 && ! C_DECLARED_LABEL_FLAG (decl))
2587 return shadow_label (id);
2588 return decl;
2589 }
2590
2591 decl = build_decl (LABEL_DECL, id, void_type_node);
2592
2593 /* A label not explicitly declared must be local to where it's ref'd. */
2594 DECL_CONTEXT (decl) = current_function_decl;
2595
2596 DECL_MODE (decl) = VOIDmode;
2597
2598 /* Say where one reference is to the label,
2599 for the sake of the error if it is not defined. */
2600 DECL_SOURCE_LINE (decl) = lineno;
2601 DECL_SOURCE_FILE (decl) = input_filename;
2602
2603 IDENTIFIER_LABEL_VALUE (id) = decl;
2604
2605 named_labels = tree_cons (NULL_TREE, decl, named_labels);
2606
2607 return decl;
2608 }
2609
2610 /* Make a label named NAME in the current function,
2611 shadowing silently any that may be inherited from containing functions
2612 or containing scopes.
2613
2614 Note that valid use, if the label being shadowed
2615 comes from another scope in the same function,
2616 requires calling declare_nonlocal_label right away. */
2617
2618 tree
2619 shadow_label (name)
2620 tree name;
2621 {
2622 tree decl = IDENTIFIER_LABEL_VALUE (name);
2623
2624 if (decl != 0)
2625 {
2626 tree dup;
2627
2628 /* Check to make sure that the label hasn't already been declared
2629 at this label scope */
2630 for (dup = named_labels; dup; dup = TREE_CHAIN (dup))
2631 if (TREE_VALUE (dup) == decl)
2632 {
2633 error ("duplicate label declaration `%s'",
2634 IDENTIFIER_POINTER (name));
2635 error_with_decl (TREE_VALUE (dup),
2636 "this is a previous declaration");
2637 /* Just use the previous declaration. */
2638 return lookup_label (name);
2639 }
2640
2641 shadowed_labels = tree_cons (NULL_TREE, decl, shadowed_labels);
2642 IDENTIFIER_LABEL_VALUE (name) = decl = 0;
2643 }
2644
2645 return lookup_label (name);
2646 }
2647
2648 /* Define a label, specifying the location in the source file.
2649 Return the LABEL_DECL node for the label, if the definition is valid.
2650 Otherwise return 0. */
2651
2652 tree
2653 define_label (filename, line, name)
2654 const char *filename;
2655 int line;
2656 tree name;
2657 {
2658 tree decl = lookup_label (name);
2659
2660 /* If label with this name is known from an outer context, shadow it. */
2661 if (decl != 0 && DECL_CONTEXT (decl) != current_function_decl)
2662 {
2663 shadowed_labels = tree_cons (NULL_TREE, decl, shadowed_labels);
2664 IDENTIFIER_LABEL_VALUE (name) = 0;
2665 decl = lookup_label (name);
2666 }
2667
2668 if (warn_traditional && !in_system_header && lookup_name (name))
2669 warning_with_file_and_line (filename, line,
2670 "traditional C lacks a separate namespace for labels, identifier `%s' conflicts",
2671 IDENTIFIER_POINTER (name));
2672
2673 if (DECL_INITIAL (decl) != 0)
2674 {
2675 error_with_file_and_line (filename, line, "duplicate label `%s'",
2676 IDENTIFIER_POINTER (name));
2677 return 0;
2678 }
2679 else
2680 {
2681 /* Mark label as having been defined. */
2682 DECL_INITIAL (decl) = error_mark_node;
2683 /* Say where in the source. */
2684 DECL_SOURCE_FILE (decl) = filename;
2685 DECL_SOURCE_LINE (decl) = line;
2686 return decl;
2687 }
2688 }
2689 \f
2690 /* Return the list of declarations of the current level.
2691 Note that this list is in reverse order unless/until
2692 you nreverse it; and when you do nreverse it, you must
2693 store the result back using `storedecls' or you will lose. */
2694
2695 tree
2696 getdecls ()
2697 {
2698 return current_binding_level->names;
2699 }
2700
2701 /* Return the list of type-tags (for structs, etc) of the current level. */
2702
2703 tree
2704 gettags ()
2705 {
2706 return current_binding_level->tags;
2707 }
2708
2709 /* Store the list of declarations of the current level.
2710 This is done for the parameter declarations of a function being defined,
2711 after they are modified in the light of any missing parameters. */
2712
2713 static void
2714 storedecls (decls)
2715 tree decls;
2716 {
2717 current_binding_level->names = decls;
2718 }
2719
2720 /* Similarly, store the list of tags of the current level. */
2721
2722 static void
2723 storetags (tags)
2724 tree tags;
2725 {
2726 current_binding_level->tags = tags;
2727 }
2728 \f
2729 /* Given NAME, an IDENTIFIER_NODE,
2730 return the structure (or union or enum) definition for that name.
2731 Searches binding levels from BINDING_LEVEL up to the global level.
2732 If THISLEVEL_ONLY is nonzero, searches only the specified context
2733 (but skips any tag-transparent contexts to find one that is
2734 meaningful for tags).
2735 CODE says which kind of type the caller wants;
2736 it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
2737 If the wrong kind of type is found, an error is reported. */
2738
2739 static tree
2740 lookup_tag (code, name, binding_level, thislevel_only)
2741 enum tree_code code;
2742 struct binding_level *binding_level;
2743 tree name;
2744 int thislevel_only;
2745 {
2746 struct binding_level *level;
2747 int thislevel = 1;
2748
2749 for (level = binding_level; level; level = level->level_chain)
2750 {
2751 tree tail;
2752 for (tail = level->tags; tail; tail = TREE_CHAIN (tail))
2753 {
2754 if (TREE_PURPOSE (tail) == name)
2755 {
2756 if (TREE_CODE (TREE_VALUE (tail)) != code)
2757 {
2758 /* Definition isn't the kind we were looking for. */
2759 pending_invalid_xref = name;
2760 pending_invalid_xref_file = input_filename;
2761 pending_invalid_xref_line = lineno;
2762 /* If in the same binding level as a declaration as a tag
2763 of a different type, this must not be allowed to
2764 shadow that tag, so give the error immediately.
2765 (For example, "struct foo; union foo;" is invalid.) */
2766 if (thislevel)
2767 pending_xref_error ();
2768 }
2769 return TREE_VALUE (tail);
2770 }
2771 }
2772 if (! level->tag_transparent)
2773 {
2774 if (thislevel_only)
2775 return NULL_TREE;
2776 thislevel = 0;
2777 }
2778 }
2779 return NULL_TREE;
2780 }
2781
2782 /* Print an error message now
2783 for a recent invalid struct, union or enum cross reference.
2784 We don't print them immediately because they are not invalid
2785 when used in the `struct foo;' construct for shadowing. */
2786
2787 void
2788 pending_xref_error ()
2789 {
2790 if (pending_invalid_xref != 0)
2791 error_with_file_and_line (pending_invalid_xref_file,
2792 pending_invalid_xref_line,
2793 "`%s' defined as wrong kind of tag",
2794 IDENTIFIER_POINTER (pending_invalid_xref));
2795 pending_invalid_xref = 0;
2796 }
2797
2798 /* Given a type, find the tag that was defined for it and return the tag name.
2799 Otherwise return 0. */
2800
2801 static tree
2802 lookup_tag_reverse (type)
2803 tree type;
2804 {
2805 struct binding_level *level;
2806
2807 for (level = current_binding_level; level; level = level->level_chain)
2808 {
2809 tree tail;
2810 for (tail = level->tags; tail; tail = TREE_CHAIN (tail))
2811 {
2812 if (TREE_VALUE (tail) == type)
2813 return TREE_PURPOSE (tail);
2814 }
2815 }
2816 return NULL_TREE;
2817 }
2818 \f
2819 /* Look up NAME in the current binding level and its superiors
2820 in the namespace of variables, functions and typedefs.
2821 Return a ..._DECL node of some kind representing its definition,
2822 or return 0 if it is undefined. */
2823
2824 tree
2825 lookup_name (name)
2826 tree name;
2827 {
2828 tree val;
2829
2830 if (current_binding_level != global_binding_level
2831 && IDENTIFIER_LOCAL_VALUE (name))
2832 val = IDENTIFIER_LOCAL_VALUE (name);
2833 else
2834 val = IDENTIFIER_GLOBAL_VALUE (name);
2835 return val;
2836 }
2837
2838 /* Similar to `lookup_name' but look only at current binding level. */
2839
2840 tree
2841 lookup_name_current_level (name)
2842 tree name;
2843 {
2844 tree t;
2845
2846 if (current_binding_level == global_binding_level)
2847 return IDENTIFIER_GLOBAL_VALUE (name);
2848
2849 if (IDENTIFIER_LOCAL_VALUE (name) == 0)
2850 return 0;
2851
2852 for (t = current_binding_level->names; t; t = TREE_CHAIN (t))
2853 if (DECL_NAME (t) == name)
2854 break;
2855
2856 return t;
2857 }
2858 \f
2859 /* Create the predefined scalar types of C,
2860 and some nodes representing standard constants (0, 1, (void *) 0).
2861 Initialize the global binding level.
2862 Make definitions for built-in primitive functions. */
2863
2864 void
2865 c_init_decl_processing ()
2866 {
2867 tree endlink;
2868 tree ptr_ftype_void, ptr_ftype_ptr;
2869
2870 /* Adds some ggc roots, and reserved words for c-parse.in. */
2871 c_parse_init ();
2872
2873 current_function_decl = NULL;
2874 named_labels = NULL;
2875 current_binding_level = NULL_BINDING_LEVEL;
2876 free_binding_level = NULL_BINDING_LEVEL;
2877
2878 /* Make the binding_level structure for global names. */
2879 pushlevel (0);
2880 global_binding_level = current_binding_level;
2881
2882 build_common_tree_nodes (flag_signed_char);
2883
2884 c_common_nodes_and_builtins ();
2885
2886 boolean_type_node = integer_type_node;
2887 boolean_true_node = integer_one_node;
2888 boolean_false_node = integer_zero_node;
2889
2890 c_bool_type_node = make_unsigned_type (BOOL_TYPE_SIZE);
2891 TREE_SET_CODE (c_bool_type_node, BOOLEAN_TYPE);
2892 TYPE_MAX_VALUE (c_bool_type_node) = build_int_2 (1, 0);
2893 TREE_TYPE (TYPE_MAX_VALUE (c_bool_type_node)) = c_bool_type_node;
2894 TYPE_PRECISION (c_bool_type_node) = 1;
2895 pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
2896 c_bool_type_node));
2897 c_bool_false_node = build_int_2 (0, 0);
2898 TREE_TYPE (c_bool_false_node) = c_bool_type_node;
2899 c_bool_true_node = build_int_2 (1, 0);
2900 TREE_TYPE (c_bool_true_node) = c_bool_type_node;
2901
2902 endlink = void_list_node;
2903 ptr_ftype_void = build_function_type (ptr_type_node, endlink);
2904 ptr_ftype_ptr
2905 = build_function_type (ptr_type_node,
2906 tree_cons (NULL_TREE, ptr_type_node, endlink));
2907
2908 pedantic_lvalues = pedantic;
2909
2910 make_fname_decl = c_make_fname_decl;
2911 start_fname_decls ();
2912 }
2913
2914 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
2915 decl, NAME is the initialization string and TYPE_DEP indicates whether
2916 NAME depended on the type of the function. As we don't yet implement
2917 delayed emission of static data, we mark the decl as emitted
2918 so it is not placed in the output. Anything using it must therefore pull
2919 out the STRING_CST initializer directly. This does mean that these names
2920 are string merging candidates, which is wrong for C99's __func__. FIXME. */
2921
2922 static tree
2923 c_make_fname_decl (id, type_dep)
2924 tree id;
2925 int type_dep;
2926 {
2927 const char *name = fname_as_string (type_dep);
2928 tree decl, type, init;
2929 size_t length = strlen (name);
2930
2931 type = build_array_type
2932 (build_qualified_type (char_type_node, TYPE_QUAL_CONST),
2933 build_index_type (size_int (length)));
2934
2935 decl = build_decl (VAR_DECL, id, type);
2936 /* We don't push the decl, so have to set its context here. */
2937 DECL_CONTEXT (decl) = current_function_decl;
2938
2939 TREE_STATIC (decl) = 1;
2940 TREE_READONLY (decl) = 1;
2941 DECL_ARTIFICIAL (decl) = 1;
2942
2943 init = build_string (length + 1, name);
2944 TREE_TYPE (init) = type;
2945 DECL_INITIAL (decl) = init;
2946
2947 TREE_USED (decl) = 1;
2948
2949 finish_decl (decl, init, NULL_TREE);
2950
2951 return decl;
2952 }
2953
2954 /* Return a definition for a builtin function named NAME and whose data type
2955 is TYPE. TYPE should be a function type with argument types.
2956 FUNCTION_CODE tells later passes how to compile calls to this function.
2957 See tree.h for its possible values.
2958
2959 If LIBRARY_NAME is nonzero, use that for DECL_ASSEMBLER_NAME,
2960 the name to be called if we can't opencode the function. */
2961
2962 tree
2963 builtin_function (name, type, function_code, class, library_name)
2964 const char *name;
2965 tree type;
2966 int function_code;
2967 enum built_in_class class;
2968 const char *library_name;
2969 {
2970 tree decl = build_decl (FUNCTION_DECL, get_identifier (name), type);
2971 DECL_EXTERNAL (decl) = 1;
2972 TREE_PUBLIC (decl) = 1;
2973 if (library_name)
2974 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (library_name));
2975 make_decl_rtl (decl, NULL);
2976 pushdecl (decl);
2977 DECL_BUILT_IN_CLASS (decl) = class;
2978 DECL_FUNCTION_CODE (decl) = function_code;
2979
2980 /* The return builtins leave the current function. */
2981 if (function_code == BUILT_IN_RETURN || function_code == BUILT_IN_EH_RETURN)
2982 TREE_THIS_VOLATILE (decl) = 1;
2983
2984 /* Warn if a function in the namespace for users
2985 is used without an occasion to consider it declared. */
2986 if (name[0] != '_' || name[1] != '_')
2987 C_DECL_ANTICIPATED (decl) = 1;
2988
2989 /* Possibly apply some default attributes to this built-in function. */
2990 decl_attributes (&decl, NULL_TREE, 0);
2991
2992 return decl;
2993 }
2994
2995 /* Apply default attributes to a function, if a system function with default
2996 attributes. */
2997
2998 void
2999 c_insert_default_attributes (decl)
3000 tree decl;
3001 {
3002 if (!TREE_PUBLIC (decl))
3003 return;
3004 c_common_insert_default_attributes (decl);
3005 }
3006 \f
3007 /* Called when a declaration is seen that contains no names to declare.
3008 If its type is a reference to a structure, union or enum inherited
3009 from a containing scope, shadow that tag name for the current scope
3010 with a forward reference.
3011 If its type defines a new named structure or union
3012 or defines an enum, it is valid but we need not do anything here.
3013 Otherwise, it is an error. */
3014
3015 void
3016 shadow_tag (declspecs)
3017 tree declspecs;
3018 {
3019 shadow_tag_warned (declspecs, 0);
3020 }
3021
3022 void
3023 shadow_tag_warned (declspecs, warned)
3024 tree declspecs;
3025 int warned;
3026 /* 1 => we have done a pedwarn. 2 => we have done a warning, but
3027 no pedwarn. */
3028 {
3029 int found_tag = 0;
3030 tree link;
3031 tree specs, attrs;
3032
3033 pending_invalid_xref = 0;
3034
3035 /* Remove the attributes from declspecs, since they will confuse the
3036 following code. */
3037 split_specs_attrs (declspecs, &specs, &attrs);
3038
3039 for (link = specs; link; link = TREE_CHAIN (link))
3040 {
3041 tree value = TREE_VALUE (link);
3042 enum tree_code code = TREE_CODE (value);
3043
3044 if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
3045 /* Used to test also that TYPE_SIZE (value) != 0.
3046 That caused warning for `struct foo;' at top level in the file. */
3047 {
3048 tree name = lookup_tag_reverse (value);
3049 tree t;
3050
3051 found_tag++;
3052
3053 if (name == 0)
3054 {
3055 if (warned != 1 && code != ENUMERAL_TYPE)
3056 /* Empty unnamed enum OK */
3057 {
3058 pedwarn ("unnamed struct/union that defines no instances");
3059 warned = 1;
3060 }
3061 }
3062 else
3063 {
3064 t = lookup_tag (code, name, current_binding_level, 1);
3065
3066 if (t == 0)
3067 {
3068 t = make_node (code);
3069 pushtag (name, t);
3070 }
3071 }
3072 }
3073 else
3074 {
3075 if (!warned && ! in_system_header)
3076 {
3077 warning ("useless keyword or type name in empty declaration");
3078 warned = 2;
3079 }
3080 }
3081 }
3082
3083 if (found_tag > 1)
3084 error ("two types specified in one empty declaration");
3085
3086 if (warned != 1)
3087 {
3088 if (found_tag == 0)
3089 pedwarn ("empty declaration");
3090 }
3091 }
3092 \f
3093 /* Construct an array declarator. EXPR is the expression inside [], or
3094 NULL_TREE. QUALS are the type qualifiers inside the [] (to be applied
3095 to the pointer to which a parameter array is converted). STATIC_P is
3096 non-zero if "static" is inside the [], zero otherwise. VLA_UNSPEC_P
3097 is non-zero is the array is [*], a VLA of unspecified length which is
3098 nevertheless a complete type (not currently implemented by GCC),
3099 zero otherwise. The declarator is constructed as an ARRAY_REF
3100 (to be decoded by grokdeclarator), whose operand 0 is what's on the
3101 left of the [] (filled by in set_array_declarator_type) and operand 1
3102 is the expression inside; whose TREE_TYPE is the type qualifiers and
3103 which has TREE_STATIC set if "static" is used. */
3104
3105 tree
3106 build_array_declarator (expr, quals, static_p, vla_unspec_p)
3107 tree expr;
3108 tree quals;
3109 int static_p;
3110 int vla_unspec_p;
3111 {
3112 tree decl;
3113 decl = build_nt (ARRAY_REF, NULL_TREE, expr);
3114 TREE_TYPE (decl) = quals;
3115 TREE_STATIC (decl) = (static_p ? 1 : 0);
3116 if (pedantic && !flag_isoc99)
3117 {
3118 if (static_p || quals != NULL_TREE)
3119 pedwarn ("ISO C89 does not support `static' or type qualifiers in parameter array declarators");
3120 if (vla_unspec_p)
3121 pedwarn ("ISO C89 does not support `[*]' array declarators");
3122 }
3123 if (vla_unspec_p)
3124 warning ("GCC does not yet properly implement `[*]' array declarators");
3125 return decl;
3126 }
3127
3128 /* Set the type of an array declarator. DECL is the declarator, as
3129 constructed by build_array_declarator; TYPE is what appears on the left
3130 of the [] and goes in operand 0. ABSTRACT_P is non-zero if it is an
3131 abstract declarator, zero otherwise; this is used to reject static and
3132 type qualifiers in abstract declarators, where they are not in the
3133 C99 grammar. */
3134
3135 tree
3136 set_array_declarator_type (decl, type, abstract_p)
3137 tree decl;
3138 tree type;
3139 int abstract_p;
3140 {
3141 TREE_OPERAND (decl, 0) = type;
3142 if (abstract_p && (TREE_TYPE (decl) != NULL_TREE || TREE_STATIC (decl)))
3143 error ("static or type qualifiers in abstract declarator");
3144 return decl;
3145 }
3146 \f
3147 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
3148
3149 tree
3150 groktypename (typename)
3151 tree typename;
3152 {
3153 tree specs, attrs;
3154
3155 if (TREE_CODE (typename) != TREE_LIST)
3156 return typename;
3157
3158 split_specs_attrs (TREE_PURPOSE (typename), &specs, &attrs);
3159
3160 typename = grokdeclarator (TREE_VALUE (typename), specs, TYPENAME, 0);
3161
3162 /* Apply attributes. */
3163 decl_attributes (&typename, attrs, 0);
3164
3165 return typename;
3166 }
3167
3168 /* Return a PARM_DECL node for a given pair of specs and declarator. */
3169
3170 tree
3171 groktypename_in_parm_context (typename)
3172 tree typename;
3173 {
3174 if (TREE_CODE (typename) != TREE_LIST)
3175 return typename;
3176 return grokdeclarator (TREE_VALUE (typename),
3177 TREE_PURPOSE (typename),
3178 PARM, 0);
3179 }
3180
3181 /* Decode a declarator in an ordinary declaration or data definition.
3182 This is called as soon as the type information and variable name
3183 have been parsed, before parsing the initializer if any.
3184 Here we create the ..._DECL node, fill in its type,
3185 and put it on the list of decls for the current context.
3186 The ..._DECL node is returned as the value.
3187
3188 Exception: for arrays where the length is not specified,
3189 the type is left null, to be filled in by `finish_decl'.
3190
3191 Function definitions do not come here; they go to start_function
3192 instead. However, external and forward declarations of functions
3193 do go through here. Structure field declarations are done by
3194 grokfield and not through here. */
3195
3196 tree
3197 start_decl (declarator, declspecs, initialized, attributes)
3198 tree declarator, declspecs;
3199 int initialized;
3200 tree attributes;
3201 {
3202 tree decl;
3203 tree tem;
3204
3205 /* An object declared as __attribute__((deprecated)) suppresses
3206 warnings of uses of other deprecated items. */
3207 if (lookup_attribute ("deprecated", attributes))
3208 deprecated_state = DEPRECATED_SUPPRESS;
3209
3210 decl = grokdeclarator (declarator, declspecs,
3211 NORMAL, initialized);
3212
3213 deprecated_state = DEPRECATED_NORMAL;
3214
3215 if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
3216 && MAIN_NAME_P (DECL_NAME (decl)))
3217 warning_with_decl (decl, "`%s' is usually a function");
3218
3219 if (initialized)
3220 /* Is it valid for this decl to have an initializer at all?
3221 If not, set INITIALIZED to zero, which will indirectly
3222 tell `finish_decl' to ignore the initializer once it is parsed. */
3223 switch (TREE_CODE (decl))
3224 {
3225 case TYPE_DECL:
3226 /* typedef foo = bar means give foo the same type as bar.
3227 We haven't parsed bar yet, so `finish_decl' will fix that up.
3228 Any other case of an initialization in a TYPE_DECL is an error. */
3229 if (pedantic || list_length (declspecs) > 1)
3230 {
3231 error ("typedef `%s' is initialized",
3232 IDENTIFIER_POINTER (DECL_NAME (decl)));
3233 initialized = 0;
3234 }
3235 break;
3236
3237 case FUNCTION_DECL:
3238 error ("function `%s' is initialized like a variable",
3239 IDENTIFIER_POINTER (DECL_NAME (decl)));
3240 initialized = 0;
3241 break;
3242
3243 case PARM_DECL:
3244 /* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE. */
3245 error ("parameter `%s' is initialized",
3246 IDENTIFIER_POINTER (DECL_NAME (decl)));
3247 initialized = 0;
3248 break;
3249
3250 default:
3251 /* Don't allow initializations for incomplete types
3252 except for arrays which might be completed by the initialization. */
3253
3254 /* This can happen if the array size is an undefined macro. We already
3255 gave a warning, so we don't need another one. */
3256 if (TREE_TYPE (decl) == error_mark_node)
3257 initialized = 0;
3258 else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
3259 {
3260 /* A complete type is ok if size is fixed. */
3261
3262 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
3263 || C_DECL_VARIABLE_SIZE (decl))
3264 {
3265 error ("variable-sized object may not be initialized");
3266 initialized = 0;
3267 }
3268 }
3269 else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
3270 {
3271 error ("variable `%s' has initializer but incomplete type",
3272 IDENTIFIER_POINTER (DECL_NAME (decl)));
3273 initialized = 0;
3274 }
3275 else if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
3276 {
3277 error ("elements of array `%s' have incomplete type",
3278 IDENTIFIER_POINTER (DECL_NAME (decl)));
3279 initialized = 0;
3280 }
3281 }
3282
3283 if (initialized)
3284 {
3285 #if 0
3286 /* Seems redundant with grokdeclarator. */
3287 if (current_binding_level != global_binding_level
3288 && DECL_EXTERNAL (decl)
3289 && TREE_CODE (decl) != FUNCTION_DECL)
3290 warning ("declaration of `%s' has `extern' and is initialized",
3291 IDENTIFIER_POINTER (DECL_NAME (decl)));
3292 #endif
3293 DECL_EXTERNAL (decl) = 0;
3294 if (current_binding_level == global_binding_level)
3295 TREE_STATIC (decl) = 1;
3296
3297 /* Tell `pushdecl' this is an initialized decl
3298 even though we don't yet have the initializer expression.
3299 Also tell `finish_decl' it may store the real initializer. */
3300 DECL_INITIAL (decl) = error_mark_node;
3301 }
3302
3303 /* If this is a function declaration, write a record describing it to the
3304 prototypes file (if requested). */
3305
3306 if (TREE_CODE (decl) == FUNCTION_DECL)
3307 gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);
3308
3309 /* ANSI specifies that a tentative definition which is not merged with
3310 a non-tentative definition behaves exactly like a definition with an
3311 initializer equal to zero. (Section 3.7.2)
3312
3313 -fno-common gives strict ANSI behavior, though this tends to break
3314 a large body of code that grew up without this rule.
3315
3316 Thread-local variables are never common, since there's no entrenched
3317 body of code to break, and it allows more efficient variable references
3318 in the presense of dynamic linking. */
3319
3320 if (TREE_CODE (decl) == VAR_DECL
3321 && !initialized
3322 && TREE_PUBLIC (decl)
3323 && !DECL_THREAD_LOCAL (decl)
3324 && !flag_no_common)
3325 DECL_COMMON (decl) = 1;
3326
3327 /* Set attributes here so if duplicate decl, will have proper attributes. */
3328 decl_attributes (&decl, attributes, 0);
3329
3330 /* If #pragma weak was used, mark the decl weak now. */
3331 if (current_binding_level == global_binding_level)
3332 maybe_apply_pragma_weak (decl);
3333
3334 if (TREE_CODE (decl) == FUNCTION_DECL
3335 && DECL_DECLARED_INLINE_P (decl)
3336 && DECL_UNINLINABLE (decl)
3337 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
3338 warning_with_decl (decl,
3339 "inline function `%s' given attribute noinline");
3340
3341 /* Add this decl to the current binding level.
3342 TEM may equal DECL or it may be a previous decl of the same name. */
3343 tem = pushdecl (decl);
3344
3345 /* For a local variable, define the RTL now. */
3346 if (current_binding_level != global_binding_level
3347 /* But not if this is a duplicate decl
3348 and we preserved the rtl from the previous one
3349 (which may or may not happen). */
3350 && !DECL_RTL_SET_P (tem)
3351 && !DECL_CONTEXT (tem))
3352 {
3353 if (TREE_TYPE (tem) != error_mark_node
3354 && COMPLETE_TYPE_P (TREE_TYPE (tem)))
3355 expand_decl (tem);
3356 else if (TREE_CODE (TREE_TYPE (tem)) == ARRAY_TYPE
3357 && DECL_INITIAL (tem) != 0)
3358 expand_decl (tem);
3359 }
3360
3361 return tem;
3362 }
3363
3364 /* Finish processing of a declaration;
3365 install its initial value.
3366 If the length of an array type is not known before,
3367 it must be determined now, from the initial value, or it is an error. */
3368
3369 void
3370 finish_decl (decl, init, asmspec_tree)
3371 tree decl, init;
3372 tree asmspec_tree;
3373 {
3374 tree type = TREE_TYPE (decl);
3375 int was_incomplete = (DECL_SIZE (decl) == 0);
3376 const char *asmspec = 0;
3377
3378 /* If a name was specified, get the string. */
3379 if (current_binding_level == global_binding_level)
3380 asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
3381 if (asmspec_tree)
3382 asmspec = TREE_STRING_POINTER (asmspec_tree);
3383
3384 /* If `start_decl' didn't like having an initialization, ignore it now. */
3385 if (init != 0 && DECL_INITIAL (decl) == 0)
3386 init = 0;
3387
3388 /* Don't crash if parm is initialized. */
3389 if (TREE_CODE (decl) == PARM_DECL)
3390 init = 0;
3391
3392 if (init)
3393 {
3394 if (TREE_CODE (decl) != TYPE_DECL)
3395 store_init_value (decl, init);
3396 else
3397 {
3398 /* typedef foo = bar; store the type of bar as the type of foo. */
3399 TREE_TYPE (decl) = TREE_TYPE (init);
3400 DECL_INITIAL (decl) = init = 0;
3401 }
3402 }
3403
3404 /* Deduce size of array from initialization, if not already known */
3405 if (TREE_CODE (type) == ARRAY_TYPE
3406 && TYPE_DOMAIN (type) == 0
3407 && TREE_CODE (decl) != TYPE_DECL)
3408 {
3409 int do_default
3410 = (TREE_STATIC (decl)
3411 /* Even if pedantic, an external linkage array
3412 may have incomplete type at first. */
3413 ? pedantic && !TREE_PUBLIC (decl)
3414 : !DECL_EXTERNAL (decl));
3415 int failure
3416 = complete_array_type (type, DECL_INITIAL (decl), do_default);
3417
3418 /* Get the completed type made by complete_array_type. */
3419 type = TREE_TYPE (decl);
3420
3421 if (failure == 1)
3422 error_with_decl (decl, "initializer fails to determine size of `%s'");
3423
3424 else if (failure == 2)
3425 {
3426 if (do_default)
3427 error_with_decl (decl, "array size missing in `%s'");
3428 /* If a `static' var's size isn't known,
3429 make it extern as well as static, so it does not get
3430 allocated.
3431 If it is not `static', then do not mark extern;
3432 finish_incomplete_decl will give it a default size
3433 and it will get allocated. */
3434 else if (!pedantic && TREE_STATIC (decl) && ! TREE_PUBLIC (decl))
3435 DECL_EXTERNAL (decl) = 1;
3436 }
3437
3438 /* TYPE_MAX_VALUE is always one less than the number of elements
3439 in the array, because we start counting at zero. Therefore,
3440 warn only if the value is less than zero. */
3441 else if (pedantic && TYPE_DOMAIN (type) != 0
3442 && tree_int_cst_sgn (TYPE_MAX_VALUE (TYPE_DOMAIN (type))) < 0)
3443 error_with_decl (decl, "zero or negative size array `%s'");
3444
3445 layout_decl (decl, 0);
3446 }
3447
3448 if (TREE_CODE (decl) == VAR_DECL)
3449 {
3450 if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
3451 && COMPLETE_TYPE_P (TREE_TYPE (decl)))
3452 layout_decl (decl, 0);
3453
3454 if (DECL_SIZE (decl) == 0
3455 /* Don't give an error if we already gave one earlier. */
3456 && TREE_TYPE (decl) != error_mark_node
3457 && (TREE_STATIC (decl)
3458 ?
3459 /* A static variable with an incomplete type
3460 is an error if it is initialized.
3461 Also if it is not file scope.
3462 Otherwise, let it through, but if it is not `extern'
3463 then it may cause an error message later. */
3464 (DECL_INITIAL (decl) != 0
3465 || DECL_CONTEXT (decl) != 0)
3466 :
3467 /* An automatic variable with an incomplete type
3468 is an error. */
3469 !DECL_EXTERNAL (decl)))
3470 {
3471 error_with_decl (decl, "storage size of `%s' isn't known");
3472 TREE_TYPE (decl) = error_mark_node;
3473 }
3474
3475 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
3476 && DECL_SIZE (decl) != 0)
3477 {
3478 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
3479 constant_expression_warning (DECL_SIZE (decl));
3480 else
3481 error_with_decl (decl, "storage size of `%s' isn't constant");
3482 }
3483
3484 if (TREE_USED (type))
3485 TREE_USED (decl) = 1;
3486 }
3487
3488 /* If this is a function and an assembler name is specified, it isn't
3489 builtin any more. Also reset DECL_RTL so we can give it its new
3490 name. */
3491 if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
3492 {
3493 DECL_BUILT_IN_CLASS (decl) = NOT_BUILT_IN;
3494 SET_DECL_RTL (decl, NULL_RTX);
3495 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (asmspec));
3496 }
3497
3498 /* Output the assembler code and/or RTL code for variables and functions,
3499 unless the type is an undefined structure or union.
3500 If not, it will get done when the type is completed. */
3501
3502 if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
3503 {
3504 /* This is a no-op in c-lang.c or something real in objc-actions.c. */
3505 maybe_objc_check_decl (decl);
3506
3507 if (!DECL_CONTEXT (decl))
3508 {
3509 if (DECL_INITIAL (decl) == NULL_TREE
3510 || DECL_INITIAL (decl) == error_mark_node)
3511 /* Don't output anything
3512 when a tentative file-scope definition is seen.
3513 But at end of compilation, do output code for them. */
3514 DECL_DEFER_OUTPUT (decl) = 1;
3515 rest_of_decl_compilation (decl, asmspec,
3516 (DECL_CONTEXT (decl) == 0
3517 || TREE_ASM_WRITTEN (decl)), 0);
3518 }
3519 else
3520 {
3521 /* This is a local variable. If there is an ASMSPEC, the
3522 user has requested that we handle it specially. */
3523 if (asmspec)
3524 {
3525 /* In conjunction with an ASMSPEC, the `register'
3526 keyword indicates that we should place the variable
3527 in a particular register. */
3528 if (DECL_REGISTER (decl))
3529 DECL_C_HARD_REGISTER (decl) = 1;
3530
3531 /* If this is not a static variable, issue a warning.
3532 It doesn't make any sense to give an ASMSPEC for an
3533 ordinary, non-register local variable. Historically,
3534 GCC has accepted -- but ignored -- the ASMSPEC in
3535 this case. */
3536 if (TREE_CODE (decl) == VAR_DECL
3537 && !DECL_REGISTER (decl)
3538 && !TREE_STATIC (decl))
3539 warning_with_decl (decl,
3540 "ignoring asm-specifier for non-static local variable `%s'");
3541 else
3542 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (asmspec));
3543 }
3544
3545 if (TREE_CODE (decl) != FUNCTION_DECL)
3546 add_decl_stmt (decl);
3547 }
3548
3549 if (DECL_CONTEXT (decl) != 0)
3550 {
3551 /* Recompute the RTL of a local array now
3552 if it used to be an incomplete type. */
3553 if (was_incomplete
3554 && ! TREE_STATIC (decl) && ! DECL_EXTERNAL (decl))
3555 {
3556 /* If we used it already as memory, it must stay in memory. */
3557 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
3558 /* If it's still incomplete now, no init will save it. */
3559 if (DECL_SIZE (decl) == 0)
3560 DECL_INITIAL (decl) = 0;
3561 }
3562 }
3563 }
3564
3565 if (TREE_CODE (decl) == TYPE_DECL)
3566 {
3567 /* This is a no-op in c-lang.c or something real in objc-actions.c. */
3568 maybe_objc_check_decl (decl);
3569 rest_of_decl_compilation (decl, NULL, DECL_CONTEXT (decl) == 0, 0);
3570 }
3571
3572 /* At the end of a declaration, throw away any variable type sizes
3573 of types defined inside that declaration. There is no use
3574 computing them in the following function definition. */
3575 if (current_binding_level == global_binding_level)
3576 get_pending_sizes ();
3577 }
3578
3579 /* Given a parsed parameter declaration,
3580 decode it into a PARM_DECL and push that on the current binding level.
3581 Also, for the sake of forward parm decls,
3582 record the given order of parms in `parm_order'. */
3583
3584 void
3585 push_parm_decl (parm)
3586 tree parm;
3587 {
3588 tree decl;
3589 int old_immediate_size_expand = immediate_size_expand;
3590 /* Don't try computing parm sizes now -- wait till fn is called. */
3591 immediate_size_expand = 0;
3592
3593 decl = grokdeclarator (TREE_VALUE (TREE_PURPOSE (parm)),
3594 TREE_PURPOSE (TREE_PURPOSE (parm)), PARM, 0);
3595 decl_attributes (&decl, TREE_VALUE (parm), 0);
3596
3597 #if 0
3598 if (DECL_NAME (decl))
3599 {
3600 tree olddecl;
3601 olddecl = lookup_name (DECL_NAME (decl));
3602 if (pedantic && olddecl != 0 && TREE_CODE (olddecl) == TYPE_DECL)
3603 pedwarn_with_decl (decl,
3604 "ISO C forbids parameter `%s' shadowing typedef");
3605 }
3606 #endif
3607
3608 decl = pushdecl (decl);
3609
3610 immediate_size_expand = old_immediate_size_expand;
3611
3612 current_binding_level->parm_order
3613 = tree_cons (NULL_TREE, decl, current_binding_level->parm_order);
3614
3615 /* Add this decl to the current binding level. */
3616 finish_decl (decl, NULL_TREE, NULL_TREE);
3617 }
3618
3619 /* Clear the given order of parms in `parm_order'.
3620 Used at start of parm list,
3621 and also at semicolon terminating forward decls. */
3622
3623 void
3624 clear_parm_order ()
3625 {
3626 current_binding_level->parm_order = NULL_TREE;
3627 }
3628 \f
3629 /* Build a COMPOUND_LITERAL_EXPR. TYPE is the type given in the compound
3630 literal, which may be an incomplete array type completed by the
3631 initializer; INIT is a CONSTRUCTOR that initializes the compound
3632 literal. */
3633
3634 tree
3635 build_compound_literal (type, init)
3636 tree type;
3637 tree init;
3638 {
3639 /* We do not use start_decl here because we have a type, not a declarator;
3640 and do not use finish_decl because the decl should be stored inside
3641 the COMPOUND_LITERAL_EXPR rather than added elsewhere as a DECL_STMT. */
3642 tree decl = build_decl (VAR_DECL, NULL_TREE, type);
3643 tree complit;
3644 tree stmt;
3645 DECL_EXTERNAL (decl) = 0;
3646 TREE_PUBLIC (decl) = 0;
3647 TREE_STATIC (decl) = (current_binding_level == global_binding_level);
3648 DECL_CONTEXT (decl) = current_function_decl;
3649 TREE_USED (decl) = 1;
3650 TREE_TYPE (decl) = type;
3651 store_init_value (decl, init);
3652
3653 if (TREE_CODE (type) == ARRAY_TYPE && !COMPLETE_TYPE_P (type))
3654 {
3655 int failure = complete_array_type (type, DECL_INITIAL (decl), 1);
3656 if (failure)
3657 abort ();
3658 }
3659
3660 type = TREE_TYPE (decl);
3661 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
3662 return error_mark_node;
3663
3664 stmt = build_stmt (DECL_STMT, decl);
3665 complit = build1 (COMPOUND_LITERAL_EXPR, TREE_TYPE (decl), stmt);
3666 TREE_SIDE_EFFECTS (complit) = 1;
3667
3668 layout_decl (decl, 0);
3669
3670 if (TREE_STATIC (decl))
3671 {
3672 /* This decl needs a name for the assembler output. We also need
3673 a unique suffix to be added to the name, for which DECL_CONTEXT
3674 must be set. */
3675 DECL_NAME (decl) = get_identifier ("__compound_literal");
3676 DECL_CONTEXT (decl) = complit;
3677 rest_of_decl_compilation (decl, NULL, 1, 0);
3678 DECL_CONTEXT (decl) = NULL_TREE;
3679 }
3680
3681 return complit;
3682 }
3683 \f
3684 /* Make TYPE a complete type based on INITIAL_VALUE.
3685 Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
3686 2 if there was no information (in which case assume 1 if DO_DEFAULT). */
3687
3688 int
3689 complete_array_type (type, initial_value, do_default)
3690 tree type;
3691 tree initial_value;
3692 int do_default;
3693 {
3694 tree maxindex = NULL_TREE;
3695 int value = 0;
3696
3697 if (initial_value)
3698 {
3699 /* Note MAXINDEX is really the maximum index,
3700 one less than the size. */
3701 if (TREE_CODE (initial_value) == STRING_CST)
3702 {
3703 int eltsize
3704 = int_size_in_bytes (TREE_TYPE (TREE_TYPE (initial_value)));
3705 maxindex = build_int_2 ((TREE_STRING_LENGTH (initial_value)
3706 / eltsize) - 1, 0);
3707 }
3708 else if (TREE_CODE (initial_value) == CONSTRUCTOR)
3709 {
3710 tree elts = CONSTRUCTOR_ELTS (initial_value);
3711 maxindex = build_int_2 (-1, -1);
3712 for (; elts; elts = TREE_CHAIN (elts))
3713 {
3714 if (TREE_PURPOSE (elts))
3715 maxindex = TREE_PURPOSE (elts);
3716 else
3717 maxindex = fold (build (PLUS_EXPR, integer_type_node,
3718 maxindex, integer_one_node));
3719 }
3720 maxindex = copy_node (maxindex);
3721 }
3722 else
3723 {
3724 /* Make an error message unless that happened already. */
3725 if (initial_value != error_mark_node)
3726 value = 1;
3727
3728 /* Prevent further error messages. */
3729 maxindex = build_int_2 (0, 0);
3730 }
3731 }
3732
3733 if (!maxindex)
3734 {
3735 if (do_default)
3736 maxindex = build_int_2 (0, 0);
3737 value = 2;
3738 }
3739
3740 if (maxindex)
3741 {
3742 TYPE_DOMAIN (type) = build_index_type (maxindex);
3743 if (!TREE_TYPE (maxindex))
3744 TREE_TYPE (maxindex) = TYPE_DOMAIN (type);
3745 }
3746
3747 /* Lay out the type now that we can get the real answer. */
3748
3749 layout_type (type);
3750
3751 return value;
3752 }
3753 \f
3754 /* Given declspecs and a declarator,
3755 determine the name and type of the object declared
3756 and construct a ..._DECL node for it.
3757 (In one case we can return a ..._TYPE node instead.
3758 For invalid input we sometimes return 0.)
3759
3760 DECLSPECS is a chain of tree_list nodes whose value fields
3761 are the storage classes and type specifiers.
3762
3763 DECL_CONTEXT says which syntactic context this declaration is in:
3764 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
3765 FUNCDEF for a function definition. Like NORMAL but a few different
3766 error messages in each case. Return value may be zero meaning
3767 this definition is too screwy to try to parse.
3768 PARM for a parameter declaration (either within a function prototype
3769 or before a function body). Make a PARM_DECL, or return void_type_node.
3770 TYPENAME if for a typename (in a cast or sizeof).
3771 Don't make a DECL node; just return the ..._TYPE node.
3772 FIELD for a struct or union field; make a FIELD_DECL.
3773 BITFIELD for a field with specified width.
3774 INITIALIZED is 1 if the decl has an initializer.
3775
3776 In the TYPENAME case, DECLARATOR is really an absolute declarator.
3777 It may also be so in the PARM case, for a prototype where the
3778 argument type is specified but not the name.
3779
3780 This function is where the complicated C meanings of `static'
3781 and `extern' are interpreted. */
3782
3783 static tree
3784 grokdeclarator (declarator, declspecs, decl_context, initialized)
3785 tree declspecs;
3786 tree declarator;
3787 enum decl_context decl_context;
3788 int initialized;
3789 {
3790 int specbits = 0;
3791 tree spec;
3792 tree type = NULL_TREE;
3793 int longlong = 0;
3794 int constp;
3795 int restrictp;
3796 int volatilep;
3797 int type_quals = TYPE_UNQUALIFIED;
3798 int inlinep;
3799 int explicit_int = 0;
3800 int explicit_char = 0;
3801 int defaulted_int = 0;
3802 tree typedef_decl = 0;
3803 const char *name;
3804 tree typedef_type = 0;
3805 int funcdef_flag = 0;
3806 enum tree_code innermost_code = ERROR_MARK;
3807 int bitfield = 0;
3808 int size_varies = 0;
3809 tree decl_attr = NULL_TREE;
3810 tree array_ptr_quals = NULL_TREE;
3811 int array_parm_static = 0;
3812 tree returned_attrs = NULL_TREE;
3813
3814 if (decl_context == BITFIELD)
3815 bitfield = 1, decl_context = FIELD;
3816
3817 if (decl_context == FUNCDEF)
3818 funcdef_flag = 1, decl_context = NORMAL;
3819
3820 /* Look inside a declarator for the name being declared
3821 and get it as a string, for an error message. */
3822 {
3823 tree decl = declarator;
3824 name = 0;
3825
3826 while (decl)
3827 switch (TREE_CODE (decl))
3828 {
3829 case ARRAY_REF:
3830 case INDIRECT_REF:
3831 case CALL_EXPR:
3832 innermost_code = TREE_CODE (decl);
3833 decl = TREE_OPERAND (decl, 0);
3834 break;
3835
3836 case TREE_LIST:
3837 decl = TREE_VALUE (decl);
3838 break;
3839
3840 case IDENTIFIER_NODE:
3841 name = IDENTIFIER_POINTER (decl);
3842 decl = 0;
3843 break;
3844
3845 default:
3846 abort ();
3847 }
3848 if (name == 0)
3849 name = "type name";
3850 }
3851
3852 /* A function definition's declarator must have the form of
3853 a function declarator. */
3854
3855 if (funcdef_flag && innermost_code != CALL_EXPR)
3856 return 0;
3857
3858 /* Anything declared one level down from the top level
3859 must be one of the parameters of a function
3860 (because the body is at least two levels down). */
3861
3862 /* If this looks like a function definition, make it one,
3863 even if it occurs where parms are expected.
3864 Then store_parm_decls will reject it and not use it as a parm. */
3865 if (decl_context == NORMAL && !funcdef_flag
3866 && current_binding_level->parm_flag)
3867 decl_context = PARM;
3868
3869 /* Look through the decl specs and record which ones appear.
3870 Some typespecs are defined as built-in typenames.
3871 Others, the ones that are modifiers of other types,
3872 are represented by bits in SPECBITS: set the bits for
3873 the modifiers that appear. Storage class keywords are also in SPECBITS.
3874
3875 If there is a typedef name or a type, store the type in TYPE.
3876 This includes builtin typedefs such as `int'.
3877
3878 Set EXPLICIT_INT or EXPLICIT_CHAR if the type is `int' or `char'
3879 and did not come from a user typedef.
3880
3881 Set LONGLONG if `long' is mentioned twice. */
3882
3883 for (spec = declspecs; spec; spec = TREE_CHAIN (spec))
3884 {
3885 tree id = TREE_VALUE (spec);
3886
3887 /* If the entire declaration is itself tagged as deprecated then
3888 suppress reports of deprecated items. */
3889 if (id && TREE_DEPRECATED (id))
3890 {
3891 if (deprecated_state != DEPRECATED_SUPPRESS)
3892 warn_deprecated_use (id);
3893 }
3894
3895 if (id == ridpointers[(int) RID_INT])
3896 explicit_int = 1;
3897 if (id == ridpointers[(int) RID_CHAR])
3898 explicit_char = 1;
3899
3900 if (TREE_CODE (id) == IDENTIFIER_NODE && C_IS_RESERVED_WORD (id))
3901 {
3902 enum rid i = C_RID_CODE (id);
3903 if ((int) i <= (int) RID_LAST_MODIFIER)
3904 {
3905 if (i == RID_LONG && (specbits & (1 << (int) RID_LONG)))
3906 {
3907 if (longlong)
3908 error ("`long long long' is too long for GCC");
3909 else
3910 {
3911 if (pedantic && !flag_isoc99 && ! in_system_header
3912 && warn_long_long)
3913 pedwarn ("ISO C89 does not support `long long'");
3914 longlong = 1;
3915 }
3916 }
3917 else if (specbits & (1 << (int) i))
3918 pedwarn ("duplicate `%s'", IDENTIFIER_POINTER (id));
3919
3920 /* Diagnose "__thread extern". Recall that this list
3921 is in the reverse order seen in the text. */
3922 if (i == RID_THREAD
3923 && (specbits & (1 << (int) RID_EXTERN
3924 | 1 << (int) RID_STATIC)))
3925 {
3926 if (specbits & 1 << (int) RID_EXTERN)
3927 error ("`__thread' before `extern'");
3928 else
3929 error ("`__thread' before `static'");
3930 }
3931
3932 specbits |= 1 << (int) i;
3933 goto found;
3934 }
3935 }
3936 if (type)
3937 error ("two or more data types in declaration of `%s'", name);
3938 /* Actual typedefs come to us as TYPE_DECL nodes. */
3939 else if (TREE_CODE (id) == TYPE_DECL)
3940 {
3941 if (TREE_TYPE (id) == error_mark_node)
3942 ; /* Allow the type to default to int to avoid cascading errors. */
3943 else
3944 {
3945 type = TREE_TYPE (id);
3946 decl_attr = DECL_ATTRIBUTES (id);
3947 typedef_decl = id;
3948 }
3949 }
3950 /* Built-in types come as identifiers. */
3951 else if (TREE_CODE (id) == IDENTIFIER_NODE)
3952 {
3953 tree t = lookup_name (id);
3954 if (TREE_TYPE (t) == error_mark_node)
3955 ;
3956 else if (!t || TREE_CODE (t) != TYPE_DECL)
3957 error ("`%s' fails to be a typedef or built in type",
3958 IDENTIFIER_POINTER (id));
3959 else
3960 {
3961 type = TREE_TYPE (t);
3962 typedef_decl = t;
3963 }
3964 }
3965 else if (TREE_CODE (id) != ERROR_MARK)
3966 type = id;
3967
3968 found:
3969 ;
3970 }
3971
3972 typedef_type = type;
3973 if (type)
3974 size_varies = C_TYPE_VARIABLE_SIZE (type);
3975
3976 /* No type at all: default to `int', and set DEFAULTED_INT
3977 because it was not a user-defined typedef. */
3978
3979 if (type == 0)
3980 {
3981 if ((! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
3982 | (1 << (int) RID_SIGNED)
3983 | (1 << (int) RID_UNSIGNED)
3984 | (1 << (int) RID_COMPLEX))))
3985 /* Don't warn about typedef foo = bar. */
3986 && ! (specbits & (1 << (int) RID_TYPEDEF) && initialized)
3987 && ! in_system_header)
3988 {
3989 /* Issue a warning if this is an ISO C 99 program or if -Wreturn-type
3990 and this is a function, or if -Wimplicit; prefer the former
3991 warning since it is more explicit. */
3992 if ((warn_implicit_int || warn_return_type || flag_isoc99)
3993 && funcdef_flag)
3994 warn_about_return_type = 1;
3995 else if (warn_implicit_int || flag_isoc99)
3996 pedwarn_c99 ("type defaults to `int' in declaration of `%s'",
3997 name);
3998 }
3999
4000 defaulted_int = 1;
4001 type = integer_type_node;
4002 }
4003
4004 /* Now process the modifiers that were specified
4005 and check for invalid combinations. */
4006
4007 /* Long double is a special combination. */
4008
4009 if ((specbits & 1 << (int) RID_LONG) && ! longlong
4010 && TYPE_MAIN_VARIANT (type) == double_type_node)
4011 {
4012 specbits &= ~(1 << (int) RID_LONG);
4013 type = long_double_type_node;
4014 }
4015
4016 /* Check all other uses of type modifiers. */
4017
4018 if (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4019 | (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED)))
4020 {
4021 int ok = 0;
4022
4023 if ((specbits & 1 << (int) RID_LONG)
4024 && (specbits & 1 << (int) RID_SHORT))
4025 error ("both long and short specified for `%s'", name);
4026 else if (((specbits & 1 << (int) RID_LONG)
4027 || (specbits & 1 << (int) RID_SHORT))
4028 && explicit_char)
4029 error ("long or short specified with char for `%s'", name);
4030 else if (((specbits & 1 << (int) RID_LONG)
4031 || (specbits & 1 << (int) RID_SHORT))
4032 && TREE_CODE (type) == REAL_TYPE)
4033 {
4034 static int already = 0;
4035
4036 error ("long or short specified with floating type for `%s'", name);
4037 if (! already && ! pedantic)
4038 {
4039 error ("the only valid combination is `long double'");
4040 already = 1;
4041 }
4042 }
4043 else if ((specbits & 1 << (int) RID_SIGNED)
4044 && (specbits & 1 << (int) RID_UNSIGNED))
4045 error ("both signed and unsigned specified for `%s'", name);
4046 else if (TREE_CODE (type) != INTEGER_TYPE)
4047 error ("long, short, signed or unsigned invalid for `%s'", name);
4048 else
4049 {
4050 ok = 1;
4051 if (!explicit_int && !defaulted_int && !explicit_char && pedantic)
4052 {
4053 pedwarn ("long, short, signed or unsigned used invalidly for `%s'",
4054 name);
4055 if (flag_pedantic_errors)
4056 ok = 0;
4057 }
4058 }
4059
4060 /* Discard the type modifiers if they are invalid. */
4061 if (! ok)
4062 {
4063 specbits &= ~((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4064 | (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED));
4065 longlong = 0;
4066 }
4067 }
4068
4069 if ((specbits & (1 << (int) RID_COMPLEX))
4070 && TREE_CODE (type) != INTEGER_TYPE && TREE_CODE (type) != REAL_TYPE)
4071 {
4072 error ("complex invalid for `%s'", name);
4073 specbits &= ~(1 << (int) RID_COMPLEX);
4074 }
4075
4076 /* Decide whether an integer type is signed or not.
4077 Optionally treat bitfields as signed by default. */
4078 if (specbits & 1 << (int) RID_UNSIGNED
4079 || (bitfield && ! flag_signed_bitfields
4080 && (explicit_int || defaulted_int || explicit_char
4081 /* A typedef for plain `int' without `signed'
4082 can be controlled just like plain `int'. */
4083 || ! (typedef_decl != 0
4084 && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
4085 && TREE_CODE (type) != ENUMERAL_TYPE
4086 && !(specbits & 1 << (int) RID_SIGNED)))
4087 {
4088 if (longlong)
4089 type = long_long_unsigned_type_node;
4090 else if (specbits & 1 << (int) RID_LONG)
4091 type = long_unsigned_type_node;
4092 else if (specbits & 1 << (int) RID_SHORT)
4093 type = short_unsigned_type_node;
4094 else if (type == char_type_node)
4095 type = unsigned_char_type_node;
4096 else if (typedef_decl)
4097 type = c_common_unsigned_type (type);
4098 else
4099 type = unsigned_type_node;
4100 }
4101 else if ((specbits & 1 << (int) RID_SIGNED)
4102 && type == char_type_node)
4103 type = signed_char_type_node;
4104 else if (longlong)
4105 type = long_long_integer_type_node;
4106 else if (specbits & 1 << (int) RID_LONG)
4107 type = long_integer_type_node;
4108 else if (specbits & 1 << (int) RID_SHORT)
4109 type = short_integer_type_node;
4110
4111 if (specbits & 1 << (int) RID_COMPLEX)
4112 {
4113 if (pedantic && !flag_isoc99)
4114 pedwarn ("ISO C89 does not support complex types");
4115 /* If we just have "complex", it is equivalent to
4116 "complex double", but if any modifiers at all are specified it is
4117 the complex form of TYPE. E.g, "complex short" is
4118 "complex short int". */
4119
4120 if (defaulted_int && ! longlong
4121 && ! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4122 | (1 << (int) RID_SIGNED)
4123 | (1 << (int) RID_UNSIGNED))))
4124 {
4125 if (pedantic)
4126 pedwarn ("ISO C does not support plain `complex' meaning `double complex'");
4127 type = complex_double_type_node;
4128 }
4129 else if (type == integer_type_node)
4130 {
4131 if (pedantic)
4132 pedwarn ("ISO C does not support complex integer types");
4133 type = complex_integer_type_node;
4134 }
4135 else if (type == float_type_node)
4136 type = complex_float_type_node;
4137 else if (type == double_type_node)
4138 type = complex_double_type_node;
4139 else if (type == long_double_type_node)
4140 type = complex_long_double_type_node;
4141 else
4142 {
4143 if (pedantic)
4144 pedwarn ("ISO C does not support complex integer types");
4145 type = build_complex_type (type);
4146 }
4147 }
4148
4149 /* Figure out the type qualifiers for the declaration. There are
4150 two ways a declaration can become qualified. One is something
4151 like `const int i' where the `const' is explicit. Another is
4152 something like `typedef const int CI; CI i' where the type of the
4153 declaration contains the `const'. */
4154 constp = !! (specbits & 1 << (int) RID_CONST) + TYPE_READONLY (type);
4155 restrictp = !! (specbits & 1 << (int) RID_RESTRICT) + TYPE_RESTRICT (type);
4156 volatilep = !! (specbits & 1 << (int) RID_VOLATILE) + TYPE_VOLATILE (type);
4157 inlinep = !! (specbits & (1 << (int) RID_INLINE));
4158 if (constp > 1 && ! flag_isoc99)
4159 pedwarn ("duplicate `const'");
4160 if (restrictp > 1 && ! flag_isoc99)
4161 pedwarn ("duplicate `restrict'");
4162 if (volatilep > 1 && ! flag_isoc99)
4163 pedwarn ("duplicate `volatile'");
4164 if (! flag_gen_aux_info && (TYPE_QUALS (type)))
4165 type = TYPE_MAIN_VARIANT (type);
4166 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4167 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4168 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4169
4170 /* Warn if two storage classes are given. Default to `auto'. */
4171
4172 {
4173 int nclasses = 0;
4174
4175 if (specbits & 1 << (int) RID_AUTO) nclasses++;
4176 if (specbits & 1 << (int) RID_STATIC) nclasses++;
4177 if (specbits & 1 << (int) RID_EXTERN) nclasses++;
4178 if (specbits & 1 << (int) RID_REGISTER) nclasses++;
4179 if (specbits & 1 << (int) RID_TYPEDEF) nclasses++;
4180
4181 /* "static __thread" and "extern __thread" are allowed. */
4182 if ((specbits & (1 << (int) RID_THREAD
4183 | 1 << (int) RID_STATIC
4184 | 1 << (int) RID_EXTERN)) == (1 << (int) RID_THREAD))
4185 nclasses++;
4186
4187 /* Warn about storage classes that are invalid for certain
4188 kinds of declarations (parameters, typenames, etc.). */
4189
4190 if (nclasses > 1)
4191 error ("multiple storage classes in declaration of `%s'", name);
4192 else if (funcdef_flag
4193 && (specbits
4194 & ((1 << (int) RID_REGISTER)
4195 | (1 << (int) RID_AUTO)
4196 | (1 << (int) RID_TYPEDEF)
4197 | (1 << (int) RID_THREAD))))
4198 {
4199 if (specbits & 1 << (int) RID_AUTO
4200 && (pedantic || current_binding_level == global_binding_level))
4201 pedwarn ("function definition declared `auto'");
4202 if (specbits & 1 << (int) RID_REGISTER)
4203 error ("function definition declared `register'");
4204 if (specbits & 1 << (int) RID_TYPEDEF)
4205 error ("function definition declared `typedef'");
4206 if (specbits & 1 << (int) RID_THREAD)
4207 error ("function definition declared `__thread'");
4208 specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
4209 | (1 << (int) RID_AUTO) | (1 << (int) RID_THREAD));
4210 }
4211 else if (decl_context != NORMAL && nclasses > 0)
4212 {
4213 if (decl_context == PARM && specbits & 1 << (int) RID_REGISTER)
4214 ;
4215 else
4216 {
4217 switch (decl_context)
4218 {
4219 case FIELD:
4220 error ("storage class specified for structure field `%s'",
4221 name);
4222 break;
4223 case PARM:
4224 error ("storage class specified for parameter `%s'", name);
4225 break;
4226 default:
4227 error ("storage class specified for typename");
4228 break;
4229 }
4230 specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
4231 | (1 << (int) RID_AUTO) | (1 << (int) RID_STATIC)
4232 | (1 << (int) RID_EXTERN) | (1 << (int) RID_THREAD));
4233 }
4234 }
4235 else if (specbits & 1 << (int) RID_EXTERN && initialized && ! funcdef_flag)
4236 {
4237 /* `extern' with initialization is invalid if not at top level. */
4238 if (current_binding_level == global_binding_level)
4239 warning ("`%s' initialized and declared `extern'", name);
4240 else
4241 error ("`%s' has both `extern' and initializer", name);
4242 }
4243 else if (current_binding_level == global_binding_level)
4244 {
4245 if (specbits & 1 << (int) RID_AUTO)
4246 error ("top-level declaration of `%s' specifies `auto'", name);
4247 }
4248 else
4249 {
4250 if (specbits & 1 << (int) RID_EXTERN && funcdef_flag)
4251 error ("nested function `%s' declared `extern'", name);
4252 else if ((specbits & (1 << (int) RID_THREAD
4253 | 1 << (int) RID_EXTERN
4254 | 1 << (int) RID_STATIC))
4255 == (1 << (int) RID_THREAD))
4256 {
4257 error ("function-scope `%s' implicitly auto and declared `__thread'",
4258 name);
4259 specbits &= ~(1 << (int) RID_THREAD);
4260 }
4261 }
4262 }
4263
4264 /* Now figure out the structure of the declarator proper.
4265 Descend through it, creating more complex types, until we reach
4266 the declared identifier (or NULL_TREE, in an absolute declarator). */
4267
4268 while (declarator && TREE_CODE (declarator) != IDENTIFIER_NODE)
4269 {
4270 if (type == error_mark_node)
4271 {
4272 declarator = TREE_OPERAND (declarator, 0);
4273 continue;
4274 }
4275
4276 /* Each level of DECLARATOR is either an ARRAY_REF (for ...[..]),
4277 an INDIRECT_REF (for *...),
4278 a CALL_EXPR (for ...(...)),
4279 a TREE_LIST (for nested attributes),
4280 an identifier (for the name being declared)
4281 or a null pointer (for the place in an absolute declarator
4282 where the name was omitted).
4283 For the last two cases, we have just exited the loop.
4284
4285 At this point, TYPE is the type of elements of an array,
4286 or for a function to return, or for a pointer to point to.
4287 After this sequence of ifs, TYPE is the type of the
4288 array or function or pointer, and DECLARATOR has had its
4289 outermost layer removed. */
4290
4291 if (array_ptr_quals != NULL_TREE || array_parm_static)
4292 {
4293 /* Only the innermost declarator (making a parameter be of
4294 array type which is converted to pointer type)
4295 may have static or type qualifiers. */
4296 error ("static or type qualifiers in non-parameter array declarator");
4297 array_ptr_quals = NULL_TREE;
4298 array_parm_static = 0;
4299 }
4300
4301 if (TREE_CODE (declarator) == TREE_LIST)
4302 {
4303 /* We encode a declarator with embedded attributes using
4304 a TREE_LIST. */
4305 tree attrs = TREE_PURPOSE (declarator);
4306 tree inner_decl;
4307 int attr_flags = 0;
4308 declarator = TREE_VALUE (declarator);
4309 inner_decl = declarator;
4310 while (inner_decl != NULL_TREE
4311 && TREE_CODE (inner_decl) == TREE_LIST)
4312 inner_decl = TREE_VALUE (inner_decl);
4313 if (inner_decl == NULL_TREE
4314 || TREE_CODE (inner_decl) == IDENTIFIER_NODE)
4315 attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
4316 else if (TREE_CODE (inner_decl) == CALL_EXPR)
4317 attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
4318 else if (TREE_CODE (inner_decl) == ARRAY_REF)
4319 attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
4320 returned_attrs = decl_attributes (&type,
4321 chainon (returned_attrs, attrs),
4322 attr_flags);
4323 }
4324 else if (TREE_CODE (declarator) == ARRAY_REF)
4325 {
4326 tree itype = NULL_TREE;
4327 tree size = TREE_OPERAND (declarator, 1);
4328 /* The index is a signed object `sizetype' bits wide. */
4329 tree index_type = c_common_signed_type (sizetype);
4330
4331 array_ptr_quals = TREE_TYPE (declarator);
4332 array_parm_static = TREE_STATIC (declarator);
4333
4334 declarator = TREE_OPERAND (declarator, 0);
4335
4336 /* Check for some types that there cannot be arrays of. */
4337
4338 if (VOID_TYPE_P (type))
4339 {
4340 error ("declaration of `%s' as array of voids", name);
4341 type = error_mark_node;
4342 }
4343
4344 if (TREE_CODE (type) == FUNCTION_TYPE)
4345 {
4346 error ("declaration of `%s' as array of functions", name);
4347 type = error_mark_node;
4348 }
4349
4350 if (size == error_mark_node)
4351 type = error_mark_node;
4352
4353 if (type == error_mark_node)
4354 continue;
4355
4356 /* If size was specified, set ITYPE to a range-type for that size.
4357 Otherwise, ITYPE remains null. finish_decl may figure it out
4358 from an initial value. */
4359
4360 if (size)
4361 {
4362 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4363 STRIP_TYPE_NOPS (size);
4364
4365 if (! INTEGRAL_TYPE_P (TREE_TYPE (size)))
4366 {
4367 error ("size of array `%s' has non-integer type", name);
4368 size = integer_one_node;
4369 }
4370
4371 if (pedantic && integer_zerop (size))
4372 pedwarn ("ISO C forbids zero-size array `%s'", name);
4373
4374 if (TREE_CODE (size) == INTEGER_CST)
4375 {
4376 constant_expression_warning (size);
4377 if (tree_int_cst_sgn (size) < 0)
4378 {
4379 error ("size of array `%s' is negative", name);
4380 size = integer_one_node;
4381 }
4382 }
4383 else
4384 {
4385 /* Make sure the array size remains visibly nonconstant
4386 even if it is (eg) a const variable with known value. */
4387 size_varies = 1;
4388
4389 if (!flag_isoc99 && pedantic)
4390 {
4391 if (TREE_CONSTANT (size))
4392 pedwarn ("ISO C89 forbids array `%s' whose size can't be evaluated",
4393 name);
4394 else
4395 pedwarn ("ISO C89 forbids variable-size array `%s'",
4396 name);
4397 }
4398 }
4399
4400 if (integer_zerop (size))
4401 {
4402 /* A zero-length array cannot be represented with an
4403 unsigned index type, which is what we'll get with
4404 build_index_type. Create an open-ended range instead. */
4405 itype = build_range_type (sizetype, size, NULL_TREE);
4406 }
4407 else
4408 {
4409 /* Compute the maximum valid index, that is, size - 1.
4410 Do the calculation in index_type, so that if it is
4411 a variable the computations will be done in the
4412 proper mode. */
4413 itype = fold (build (MINUS_EXPR, index_type,
4414 convert (index_type, size),
4415 convert (index_type, size_one_node)));
4416
4417 /* If that overflowed, the array is too big.
4418 ??? While a size of INT_MAX+1 technically shouldn't
4419 cause an overflow (because we subtract 1), the overflow
4420 is recorded during the conversion to index_type, before
4421 the subtraction. Handling this case seems like an
4422 unnecessary complication. */
4423 if (TREE_OVERFLOW (itype))
4424 {
4425 error ("size of array `%s' is too large", name);
4426 type = error_mark_node;
4427 continue;
4428 }
4429
4430 if (size_varies)
4431 itype = variable_size (itype);
4432 itype = build_index_type (itype);
4433 }
4434 }
4435 else if (decl_context == FIELD)
4436 {
4437 if (pedantic && !flag_isoc99 && !in_system_header)
4438 pedwarn ("ISO C89 does not support flexible array members");
4439
4440 /* ISO C99 Flexible array members are effectively identical
4441 to GCC's zero-length array extension. */
4442 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4443 }
4444
4445 /* If pedantic, complain about arrays of incomplete types. */
4446
4447 if (pedantic && !COMPLETE_TYPE_P (type))
4448 pedwarn ("array type has incomplete element type");
4449
4450 #if 0
4451 /* We shouldn't have a function type here at all!
4452 Functions aren't allowed as array elements. */
4453 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4454 && (constp || volatilep))
4455 pedwarn ("ISO C forbids const or volatile function types");
4456 #endif
4457
4458 /* Build the array type itself, then merge any constancy or
4459 volatility into the target type. We must do it in this order
4460 to ensure that the TYPE_MAIN_VARIANT field of the array type
4461 is set correctly. */
4462
4463 type = build_array_type (type, itype);
4464 if (type_quals)
4465 type = c_build_qualified_type (type, type_quals);
4466
4467 if (size_varies)
4468 C_TYPE_VARIABLE_SIZE (type) = 1;
4469
4470 /* The GCC extension for zero-length arrays differs from
4471 ISO flexible array members in that sizeof yields zero. */
4472 if (size && integer_zerop (size))
4473 {
4474 layout_type (type);
4475 TYPE_SIZE (type) = bitsize_zero_node;
4476 TYPE_SIZE_UNIT (type) = size_zero_node;
4477 }
4478 if (decl_context != PARM
4479 && (array_ptr_quals != NULL_TREE || array_parm_static))
4480 {
4481 error ("static or type qualifiers in non-parameter array declarator");
4482 array_ptr_quals = NULL_TREE;
4483 array_parm_static = 0;
4484 }
4485 }
4486 else if (TREE_CODE (declarator) == CALL_EXPR)
4487 {
4488 tree arg_types;
4489
4490 /* Declaring a function type.
4491 Make sure we have a valid type for the function to return. */
4492 if (type == error_mark_node)
4493 continue;
4494
4495 size_varies = 0;
4496
4497 /* Warn about some types functions can't return. */
4498
4499 if (TREE_CODE (type) == FUNCTION_TYPE)
4500 {
4501 error ("`%s' declared as function returning a function", name);
4502 type = integer_type_node;
4503 }
4504 if (TREE_CODE (type) == ARRAY_TYPE)
4505 {
4506 error ("`%s' declared as function returning an array", name);
4507 type = integer_type_node;
4508 }
4509
4510 /* Construct the function type and go to the next
4511 inner layer of declarator. */
4512
4513 arg_types = grokparms (TREE_OPERAND (declarator, 1),
4514 funcdef_flag
4515 /* Say it's a definition
4516 only for the CALL_EXPR
4517 closest to the identifier. */
4518 && TREE_CODE (TREE_OPERAND (declarator, 0)) == IDENTIFIER_NODE);
4519 /* Type qualifiers before the return type of the function
4520 qualify the return type, not the function type. */
4521 if (type_quals)
4522 {
4523 /* Type qualifiers on a function return type are normally
4524 permitted by the standard but have no effect, so give a
4525 warning at -W. Qualifiers on a void return type have
4526 meaning as a GNU extension, and are banned on function
4527 definitions in ISO C. FIXME: strictly we shouldn't
4528 pedwarn for qualified void return types except on function
4529 definitions, but not doing so could lead to the undesirable
4530 state of a "volatile void" function return type not being
4531 warned about, and a use of the function being compiled
4532 with GNU semantics, with no diagnostics under -pedantic. */
4533 if (VOID_TYPE_P (type) && pedantic && !in_system_header)
4534 pedwarn ("ISO C forbids qualified void function return type");
4535 else if (extra_warnings
4536 && !(VOID_TYPE_P (type)
4537 && type_quals == TYPE_QUAL_VOLATILE))
4538 warning ("type qualifiers ignored on function return type");
4539
4540 type = c_build_qualified_type (type, type_quals);
4541 }
4542 type_quals = TYPE_UNQUALIFIED;
4543
4544 type = build_function_type (type, arg_types);
4545 declarator = TREE_OPERAND (declarator, 0);
4546
4547 /* Set the TYPE_CONTEXTs for each tagged type which is local to
4548 the formal parameter list of this FUNCTION_TYPE to point to
4549 the FUNCTION_TYPE node itself. */
4550
4551 {
4552 tree link;
4553
4554 for (link = last_function_parm_tags;
4555 link;
4556 link = TREE_CHAIN (link))
4557 TYPE_CONTEXT (TREE_VALUE (link)) = type;
4558 }
4559 }
4560 else if (TREE_CODE (declarator) == INDIRECT_REF)
4561 {
4562 /* Merge any constancy or volatility into the target type
4563 for the pointer. */
4564
4565 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4566 && type_quals)
4567 pedwarn ("ISO C forbids qualified function types");
4568 if (type_quals)
4569 type = c_build_qualified_type (type, type_quals);
4570 type_quals = TYPE_UNQUALIFIED;
4571 size_varies = 0;
4572
4573 type = build_pointer_type (type);
4574
4575 /* Process a list of type modifier keywords
4576 (such as const or volatile) that were given inside the `*'. */
4577
4578 if (TREE_TYPE (declarator))
4579 {
4580 tree typemodlist;
4581 int erred = 0;
4582
4583 constp = 0;
4584 volatilep = 0;
4585 restrictp = 0;
4586 for (typemodlist = TREE_TYPE (declarator); typemodlist;
4587 typemodlist = TREE_CHAIN (typemodlist))
4588 {
4589 tree qualifier = TREE_VALUE (typemodlist);
4590
4591 if (C_IS_RESERVED_WORD (qualifier))
4592 {
4593 if (C_RID_CODE (qualifier) == RID_CONST)
4594 constp++;
4595 else if (C_RID_CODE (qualifier) == RID_VOLATILE)
4596 volatilep++;
4597 else if (C_RID_CODE (qualifier) == RID_RESTRICT)
4598 restrictp++;
4599 else
4600 erred++;
4601 }
4602 else
4603 erred++;
4604 }
4605
4606 if (erred)
4607 error ("invalid type modifier within pointer declarator");
4608 if (constp > 1 && ! flag_isoc99)
4609 pedwarn ("duplicate `const'");
4610 if (volatilep > 1 && ! flag_isoc99)
4611 pedwarn ("duplicate `volatile'");
4612 if (restrictp > 1 && ! flag_isoc99)
4613 pedwarn ("duplicate `restrict'");
4614
4615 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4616 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4617 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4618 }
4619
4620 declarator = TREE_OPERAND (declarator, 0);
4621 }
4622 else
4623 abort ();
4624
4625 }
4626
4627 /* Now TYPE has the actual type. */
4628
4629 /* Did array size calculations overflow? */
4630
4631 if (TREE_CODE (type) == ARRAY_TYPE
4632 && COMPLETE_TYPE_P (type)
4633 && TREE_OVERFLOW (TYPE_SIZE (type)))
4634 {
4635 error ("size of array `%s' is too large", name);
4636 /* If we proceed with the array type as it is, we'll eventually
4637 crash in tree_low_cst(). */
4638 type = error_mark_node;
4639 }
4640
4641 /* If this is declaring a typedef name, return a TYPE_DECL. */
4642
4643 if (specbits & (1 << (int) RID_TYPEDEF))
4644 {
4645 tree decl;
4646 /* Note that the grammar rejects storage classes
4647 in typenames, fields or parameters */
4648 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4649 && type_quals)
4650 pedwarn ("ISO C forbids qualified function types");
4651 if (type_quals)
4652 type = c_build_qualified_type (type, type_quals);
4653 decl = build_decl (TYPE_DECL, declarator, type);
4654 if ((specbits & (1 << (int) RID_SIGNED))
4655 || (typedef_decl && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
4656 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
4657 decl_attributes (&decl, returned_attrs, 0);
4658 return decl;
4659 }
4660
4661 /* Detect the case of an array type of unspecified size
4662 which came, as such, direct from a typedef name.
4663 We must copy the type, so that each identifier gets
4664 a distinct type, so that each identifier's size can be
4665 controlled separately by its own initializer. */
4666
4667 if (type != 0 && typedef_type != 0
4668 && TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == 0
4669 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (typedef_type))
4670 {
4671 type = build_array_type (TREE_TYPE (type), 0);
4672 if (size_varies)
4673 C_TYPE_VARIABLE_SIZE (type) = 1;
4674 }
4675
4676 /* If this is a type name (such as, in a cast or sizeof),
4677 compute the type and return it now. */
4678
4679 if (decl_context == TYPENAME)
4680 {
4681 /* Note that the grammar rejects storage classes
4682 in typenames, fields or parameters */
4683 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4684 && type_quals)
4685 pedwarn ("ISO C forbids const or volatile function types");
4686 if (type_quals)
4687 type = c_build_qualified_type (type, type_quals);
4688 decl_attributes (&type, returned_attrs, 0);
4689 return type;
4690 }
4691
4692 /* Aside from typedefs and type names (handle above),
4693 `void' at top level (not within pointer)
4694 is allowed only in public variables.
4695 We don't complain about parms either, but that is because
4696 a better error message can be made later. */
4697
4698 if (VOID_TYPE_P (type) && decl_context != PARM
4699 && ! ((decl_context != FIELD && TREE_CODE (type) != FUNCTION_TYPE)
4700 && ((specbits & (1 << (int) RID_EXTERN))
4701 || (current_binding_level == global_binding_level
4702 && !(specbits
4703 & ((1 << (int) RID_STATIC) | (1 << (int) RID_REGISTER)))))))
4704 {
4705 error ("variable or field `%s' declared void", name);
4706 type = integer_type_node;
4707 }
4708
4709 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
4710 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
4711
4712 {
4713 tree decl;
4714
4715 if (decl_context == PARM)
4716 {
4717 tree type_as_written;
4718 tree promoted_type;
4719
4720 /* A parameter declared as an array of T is really a pointer to T.
4721 One declared as a function is really a pointer to a function. */
4722
4723 if (TREE_CODE (type) == ARRAY_TYPE)
4724 {
4725 /* Transfer const-ness of array into that of type pointed to. */
4726 type = TREE_TYPE (type);
4727 if (type_quals)
4728 type = c_build_qualified_type (type, type_quals);
4729 type = build_pointer_type (type);
4730 type_quals = TYPE_UNQUALIFIED;
4731 if (array_ptr_quals)
4732 {
4733 tree new_ptr_quals, new_ptr_attrs;
4734 int erred = 0;
4735 split_specs_attrs (array_ptr_quals, &new_ptr_quals, &new_ptr_attrs);
4736 /* We don't yet implement attributes in this context. */
4737 if (new_ptr_attrs != NULL_TREE)
4738 warning ("attributes in parameter array declarator ignored");
4739
4740 constp = 0;
4741 volatilep = 0;
4742 restrictp = 0;
4743 for (; new_ptr_quals; new_ptr_quals = TREE_CHAIN (new_ptr_quals))
4744 {
4745 tree qualifier = TREE_VALUE (new_ptr_quals);
4746
4747 if (C_IS_RESERVED_WORD (qualifier))
4748 {
4749 if (C_RID_CODE (qualifier) == RID_CONST)
4750 constp++;
4751 else if (C_RID_CODE (qualifier) == RID_VOLATILE)
4752 volatilep++;
4753 else if (C_RID_CODE (qualifier) == RID_RESTRICT)
4754 restrictp++;
4755 else
4756 erred++;
4757 }
4758 else
4759 erred++;
4760 }
4761
4762 if (erred)
4763 error ("invalid type modifier within array declarator");
4764
4765 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4766 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4767 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4768 }
4769 size_varies = 0;
4770 }
4771 else if (TREE_CODE (type) == FUNCTION_TYPE)
4772 {
4773 if (pedantic && type_quals)
4774 pedwarn ("ISO C forbids qualified function types");
4775 if (type_quals)
4776 type = c_build_qualified_type (type, type_quals);
4777 type = build_pointer_type (type);
4778 type_quals = TYPE_UNQUALIFIED;
4779 }
4780 else if (type_quals)
4781 type = c_build_qualified_type (type, type_quals);
4782
4783 type_as_written = type;
4784
4785 decl = build_decl (PARM_DECL, declarator, type);
4786 if (size_varies)
4787 C_DECL_VARIABLE_SIZE (decl) = 1;
4788
4789 /* Compute the type actually passed in the parmlist,
4790 for the case where there is no prototype.
4791 (For example, shorts and chars are passed as ints.)
4792 When there is a prototype, this is overridden later. */
4793
4794 if (type == error_mark_node)
4795 promoted_type = type;
4796 else
4797 promoted_type = c_type_promotes_to (type);
4798
4799 DECL_ARG_TYPE (decl) = promoted_type;
4800 DECL_ARG_TYPE_AS_WRITTEN (decl) = type_as_written;
4801 }
4802 else if (decl_context == FIELD)
4803 {
4804 /* Structure field. It may not be a function. */
4805
4806 if (TREE_CODE (type) == FUNCTION_TYPE)
4807 {
4808 error ("field `%s' declared as a function", name);
4809 type = build_pointer_type (type);
4810 }
4811 else if (TREE_CODE (type) != ERROR_MARK
4812 && !COMPLETE_OR_UNBOUND_ARRAY_TYPE_P (type))
4813 {
4814 error ("field `%s' has incomplete type", name);
4815 type = error_mark_node;
4816 }
4817 /* Move type qualifiers down to element of an array. */
4818 if (TREE_CODE (type) == ARRAY_TYPE && type_quals)
4819 {
4820 type = build_array_type (c_build_qualified_type (TREE_TYPE (type),
4821 type_quals),
4822 TYPE_DOMAIN (type));
4823 #if 0
4824 /* Leave the field const or volatile as well. */
4825 type_quals = TYPE_UNQUALIFIED;
4826 #endif
4827 }
4828 decl = build_decl (FIELD_DECL, declarator, type);
4829 DECL_NONADDRESSABLE_P (decl) = bitfield;
4830
4831 if (size_varies)
4832 C_DECL_VARIABLE_SIZE (decl) = 1;
4833 }
4834 else if (TREE_CODE (type) == FUNCTION_TYPE)
4835 {
4836 /* Every function declaration is "external"
4837 except for those which are inside a function body
4838 in which `auto' is used.
4839 That is a case not specified by ANSI C,
4840 and we use it for forward declarations for nested functions. */
4841 int extern_ref = (!(specbits & (1 << (int) RID_AUTO))
4842 || current_binding_level == global_binding_level);
4843
4844 if (specbits & (1 << (int) RID_AUTO)
4845 && (pedantic || current_binding_level == global_binding_level))
4846 pedwarn ("invalid storage class for function `%s'", name);
4847 if (specbits & (1 << (int) RID_REGISTER))
4848 error ("invalid storage class for function `%s'", name);
4849 if (specbits & (1 << (int) RID_THREAD))
4850 error ("invalid storage class for function `%s'", name);
4851 /* Function declaration not at top level.
4852 Storage classes other than `extern' are not allowed
4853 and `extern' makes no difference. */
4854 if (current_binding_level != global_binding_level
4855 && (specbits & ((1 << (int) RID_STATIC) | (1 << (int) RID_INLINE)))
4856 && pedantic)
4857 pedwarn ("invalid storage class for function `%s'", name);
4858
4859 decl = build_decl (FUNCTION_DECL, declarator, type);
4860 decl = build_decl_attribute_variant (decl, decl_attr);
4861
4862 DECL_LANG_SPECIFIC (decl) = (struct lang_decl *)
4863 ggc_alloc_cleared (sizeof (struct lang_decl));
4864
4865 if (pedantic && type_quals && ! DECL_IN_SYSTEM_HEADER (decl))
4866 pedwarn ("ISO C forbids qualified function types");
4867
4868 /* GNU C interprets a `volatile void' return type to indicate
4869 that the function does not return. */
4870 if ((type_quals & TYPE_QUAL_VOLATILE)
4871 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
4872 warning ("`noreturn' function returns non-void value");
4873
4874 if (extern_ref)
4875 DECL_EXTERNAL (decl) = 1;
4876 /* Record absence of global scope for `static' or `auto'. */
4877 TREE_PUBLIC (decl)
4878 = !(specbits & ((1 << (int) RID_STATIC) | (1 << (int) RID_AUTO)));
4879
4880 if (defaulted_int)
4881 C_FUNCTION_IMPLICIT_INT (decl) = 1;
4882
4883 /* Record presence of `inline', if it is reasonable. */
4884 if (MAIN_NAME_P (declarator))
4885 {
4886 if (inlinep)
4887 warning ("cannot inline function `main'");
4888 }
4889 else if (inlinep)
4890 {
4891 /* Assume that otherwise the function can be inlined. */
4892 DECL_DECLARED_INLINE_P (decl) = 1;
4893
4894 /* Do not mark bare declarations as DECL_INLINE. Doing so
4895 in the presence of multiple declarations can result in
4896 the abstract origin pointing between the declarations,
4897 which will confuse dwarf2out. */
4898 if (initialized)
4899 {
4900 DECL_INLINE (decl) = 1;
4901 if (specbits & (1 << (int) RID_EXTERN))
4902 current_extern_inline = 1;
4903 }
4904 }
4905 /* If -finline-functions, assume it can be inlined. This does
4906 two things: let the function be deferred until it is actually
4907 needed, and let dwarf2 know that the function is inlinable. */
4908 else if (flag_inline_trees == 2 && initialized)
4909 {
4910 DECL_INLINE (decl) = 1;
4911 DECL_DECLARED_INLINE_P (decl) = 0;
4912 }
4913 }
4914 else
4915 {
4916 /* It's a variable. */
4917 /* An uninitialized decl with `extern' is a reference. */
4918 int extern_ref = !initialized && (specbits & (1 << (int) RID_EXTERN));
4919
4920 /* Move type qualifiers down to element of an array. */
4921 if (TREE_CODE (type) == ARRAY_TYPE && type_quals)
4922 {
4923 int saved_align = TYPE_ALIGN(type);
4924 type = build_array_type (c_build_qualified_type (TREE_TYPE (type),
4925 type_quals),
4926 TYPE_DOMAIN (type));
4927 TYPE_ALIGN (type) = saved_align;
4928 #if 0 /* Leave the variable const or volatile as well. */
4929 type_quals = TYPE_UNQUALIFIED;
4930 #endif
4931 }
4932 else if (type_quals)
4933 type = c_build_qualified_type (type, type_quals);
4934
4935 decl = build_decl (VAR_DECL, declarator, type);
4936 if (size_varies)
4937 C_DECL_VARIABLE_SIZE (decl) = 1;
4938
4939 if (inlinep)
4940 pedwarn_with_decl (decl, "variable `%s' declared `inline'");
4941
4942 DECL_EXTERNAL (decl) = extern_ref;
4943
4944 /* At top level, the presence of a `static' or `register' storage
4945 class specifier, or the absence of all storage class specifiers
4946 makes this declaration a definition (perhaps tentative). Also,
4947 the absence of both `static' and `register' makes it public. */
4948 if (current_binding_level == global_binding_level)
4949 {
4950 TREE_PUBLIC (decl) = !(specbits & ((1 << (int) RID_STATIC)
4951 | (1 << (int) RID_REGISTER)));
4952 TREE_STATIC (decl) = !extern_ref;
4953 }
4954 /* Not at top level, only `static' makes a static definition. */
4955 else
4956 {
4957 TREE_STATIC (decl) = (specbits & (1 << (int) RID_STATIC)) != 0;
4958 TREE_PUBLIC (decl) = extern_ref;
4959 }
4960
4961 if (specbits & 1 << (int) RID_THREAD)
4962 {
4963 if (targetm.have_tls)
4964 DECL_THREAD_LOCAL (decl) = 1;
4965 else
4966 /* A mere warning is sure to result in improper semantics
4967 at runtime. Don't bother to allow this to compile. */
4968 error ("thread-local storage not supported for this target");
4969 }
4970 }
4971
4972 /* Record `register' declaration for warnings on &
4973 and in case doing stupid register allocation. */
4974
4975 if (specbits & (1 << (int) RID_REGISTER))
4976 DECL_REGISTER (decl) = 1;
4977
4978 /* Record constancy and volatility. */
4979 c_apply_type_quals_to_decl (type_quals, decl);
4980
4981 /* If a type has volatile components, it should be stored in memory.
4982 Otherwise, the fact that those components are volatile
4983 will be ignored, and would even crash the compiler. */
4984 if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (decl)))
4985 c_mark_addressable (decl);
4986
4987 decl_attributes (&decl, returned_attrs, 0);
4988
4989 return decl;
4990 }
4991 }
4992 \f
4993 /* Decode the parameter-list info for a function type or function definition.
4994 The argument is the value returned by `get_parm_info' (or made in parse.y
4995 if there is an identifier list instead of a parameter decl list).
4996 These two functions are separate because when a function returns
4997 or receives functions then each is called multiple times but the order
4998 of calls is different. The last call to `grokparms' is always the one
4999 that contains the formal parameter names of a function definition.
5000
5001 Store in `last_function_parms' a chain of the decls of parms.
5002 Also store in `last_function_parm_tags' a chain of the struct, union,
5003 and enum tags declared among the parms.
5004
5005 Return a list of arg types to use in the FUNCTION_TYPE for this function.
5006
5007 FUNCDEF_FLAG is nonzero for a function definition, 0 for
5008 a mere declaration. A nonempty identifier-list gets an error message
5009 when FUNCDEF_FLAG is zero. */
5010
5011 static tree
5012 grokparms (parms_info, funcdef_flag)
5013 tree parms_info;
5014 int funcdef_flag;
5015 {
5016 tree first_parm = TREE_CHAIN (parms_info);
5017
5018 last_function_parms = TREE_PURPOSE (parms_info);
5019 last_function_parm_tags = TREE_VALUE (parms_info);
5020
5021 if (warn_strict_prototypes && first_parm == 0 && !funcdef_flag
5022 && !in_system_header)
5023 warning ("function declaration isn't a prototype");
5024
5025 if (first_parm != 0
5026 && TREE_CODE (TREE_VALUE (first_parm)) == IDENTIFIER_NODE)
5027 {
5028 if (! funcdef_flag)
5029 pedwarn ("parameter names (without types) in function declaration");
5030
5031 last_function_parms = first_parm;
5032 return 0;
5033 }
5034 else
5035 {
5036 tree parm;
5037 tree typelt;
5038 /* We no longer test FUNCDEF_FLAG.
5039 If the arg types are incomplete in a declaration,
5040 they must include undefined tags.
5041 These tags can never be defined in the scope of the declaration,
5042 so the types can never be completed,
5043 and no call can be compiled successfully. */
5044 #if 0
5045 /* In a fcn definition, arg types must be complete. */
5046 if (funcdef_flag)
5047 #endif
5048 for (parm = last_function_parms, typelt = first_parm;
5049 parm;
5050 parm = TREE_CHAIN (parm))
5051 /* Skip over any enumeration constants declared here. */
5052 if (TREE_CODE (parm) == PARM_DECL)
5053 {
5054 /* Barf if the parameter itself has an incomplete type. */
5055 tree type = TREE_VALUE (typelt);
5056 if (type == error_mark_node)
5057 continue;
5058 if (!COMPLETE_TYPE_P (type))
5059 {
5060 if (funcdef_flag && DECL_NAME (parm) != 0)
5061 error ("parameter `%s' has incomplete type",
5062 IDENTIFIER_POINTER (DECL_NAME (parm)));
5063 else
5064 warning ("parameter has incomplete type");
5065 if (funcdef_flag)
5066 {
5067 TREE_VALUE (typelt) = error_mark_node;
5068 TREE_TYPE (parm) = error_mark_node;
5069 }
5070 }
5071 #if 0
5072 /* This has been replaced by parm_tags_warning, which
5073 uses a more accurate criterion for what to warn
5074 about. */
5075 else
5076 {
5077 /* Now warn if is a pointer to an incomplete type. */
5078 while (TREE_CODE (type) == POINTER_TYPE
5079 || TREE_CODE (type) == REFERENCE_TYPE)
5080 type = TREE_TYPE (type);
5081 type = TYPE_MAIN_VARIANT (type);
5082 if (!COMPLETE_TYPE_P (type))
5083 {
5084 if (DECL_NAME (parm) != 0)
5085 warning ("parameter `%s' points to incomplete type",
5086 IDENTIFIER_POINTER (DECL_NAME (parm)));
5087 else
5088 warning ("parameter points to incomplete type");
5089 }
5090 }
5091 #endif
5092 typelt = TREE_CHAIN (typelt);
5093 }
5094
5095 return first_parm;
5096 }
5097 }
5098
5099 /* Return a tree_list node with info on a parameter list just parsed.
5100 The TREE_PURPOSE is a chain of decls of those parms.
5101 The TREE_VALUE is a list of structure, union and enum tags defined.
5102 The TREE_CHAIN is a list of argument types to go in the FUNCTION_TYPE.
5103 This tree_list node is later fed to `grokparms'.
5104
5105 VOID_AT_END nonzero means append `void' to the end of the type-list.
5106 Zero means the parmlist ended with an ellipsis so don't append `void'. */
5107
5108 tree
5109 get_parm_info (void_at_end)
5110 int void_at_end;
5111 {
5112 tree decl, t;
5113 tree types = 0;
5114 int erred = 0;
5115 tree tags = gettags ();
5116 tree parms = getdecls ();
5117 tree new_parms = 0;
5118 tree order = current_binding_level->parm_order;
5119
5120 /* Just `void' (and no ellipsis) is special. There are really no parms.
5121 But if the `void' is qualified (by `const' or `volatile') or has a
5122 storage class specifier (`register'), then the behavior is undefined;
5123 by not counting it as the special case of `void' we will cause an
5124 error later. Typedefs for `void' are OK (see DR#157). */
5125 if (void_at_end && parms != 0
5126 && TREE_CHAIN (parms) == 0
5127 && VOID_TYPE_P (TREE_TYPE (parms))
5128 && ! TREE_THIS_VOLATILE (parms)
5129 && ! TREE_READONLY (parms)
5130 && ! DECL_REGISTER (parms)
5131 && DECL_NAME (parms) == 0)
5132 {
5133 parms = NULL_TREE;
5134 storedecls (NULL_TREE);
5135 return tree_cons (NULL_TREE, NULL_TREE,
5136 tree_cons (NULL_TREE, void_type_node, NULL_TREE));
5137 }
5138
5139 /* Extract enumerator values and other non-parms declared with the parms.
5140 Likewise any forward parm decls that didn't have real parm decls. */
5141 for (decl = parms; decl;)
5142 {
5143 tree next = TREE_CHAIN (decl);
5144
5145 if (TREE_CODE (decl) != PARM_DECL)
5146 {
5147 TREE_CHAIN (decl) = new_parms;
5148 new_parms = decl;
5149 }
5150 else if (TREE_ASM_WRITTEN (decl))
5151 {
5152 error_with_decl (decl,
5153 "parameter `%s' has just a forward declaration");
5154 TREE_CHAIN (decl) = new_parms;
5155 new_parms = decl;
5156 }
5157 decl = next;
5158 }
5159
5160 /* Put the parm decls back in the order they were in in the parm list. */
5161 for (t = order; t; t = TREE_CHAIN (t))
5162 {
5163 if (TREE_CHAIN (t))
5164 TREE_CHAIN (TREE_VALUE (t)) = TREE_VALUE (TREE_CHAIN (t));
5165 else
5166 TREE_CHAIN (TREE_VALUE (t)) = 0;
5167 }
5168
5169 new_parms = chainon (order ? nreverse (TREE_VALUE (order)) : 0,
5170 new_parms);
5171
5172 /* Store the parmlist in the binding level since the old one
5173 is no longer a valid list. (We have changed the chain pointers.) */
5174 storedecls (new_parms);
5175
5176 for (decl = new_parms; decl; decl = TREE_CHAIN (decl))
5177 /* There may also be declarations for enumerators if an enumeration
5178 type is declared among the parms. Ignore them here. */
5179 if (TREE_CODE (decl) == PARM_DECL)
5180 {
5181 /* Since there is a prototype,
5182 args are passed in their declared types. */
5183 tree type = TREE_TYPE (decl);
5184 DECL_ARG_TYPE (decl) = type;
5185 if (PROMOTE_PROTOTYPES
5186 && INTEGRAL_TYPE_P (type)
5187 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
5188 DECL_ARG_TYPE (decl) = integer_type_node;
5189
5190 types = tree_cons (NULL_TREE, TREE_TYPE (decl), types);
5191 if (VOID_TYPE_P (TREE_VALUE (types)) && ! erred
5192 && DECL_NAME (decl) == 0)
5193 {
5194 error ("`void' in parameter list must be the entire list");
5195 erred = 1;
5196 }
5197 }
5198
5199 if (void_at_end)
5200 return tree_cons (new_parms, tags,
5201 nreverse (tree_cons (NULL_TREE, void_type_node, types)));
5202
5203 return tree_cons (new_parms, tags, nreverse (types));
5204 }
5205
5206 /* At end of parameter list, warn about any struct, union or enum tags
5207 defined within. Do so because these types cannot ever become complete. */
5208
5209 void
5210 parmlist_tags_warning ()
5211 {
5212 tree elt;
5213 static int already;
5214
5215 for (elt = current_binding_level->tags; elt; elt = TREE_CHAIN (elt))
5216 {
5217 enum tree_code code = TREE_CODE (TREE_VALUE (elt));
5218 /* An anonymous union parm type is meaningful as a GNU extension.
5219 So don't warn for that. */
5220 if (code == UNION_TYPE && TREE_PURPOSE (elt) == 0 && !pedantic)
5221 continue;
5222 if (TREE_PURPOSE (elt) != 0)
5223 {
5224 if (code == RECORD_TYPE)
5225 warning ("`struct %s' declared inside parameter list",
5226 IDENTIFIER_POINTER (TREE_PURPOSE (elt)));
5227 else if (code == UNION_TYPE)
5228 warning ("`union %s' declared inside parameter list",
5229 IDENTIFIER_POINTER (TREE_PURPOSE (elt)));
5230 else
5231 warning ("`enum %s' declared inside parameter list",
5232 IDENTIFIER_POINTER (TREE_PURPOSE (elt)));
5233 }
5234 else
5235 {
5236 /* For translation these need to be separate warnings */
5237 if (code == RECORD_TYPE)
5238 warning ("anonymous struct declared inside parameter list");
5239 else if (code == UNION_TYPE)
5240 warning ("anonymous union declared inside parameter list");
5241 else
5242 warning ("anonymous enum declared inside parameter list");
5243 }
5244 if (! already)
5245 {
5246 warning ("its scope is only this definition or declaration, which is probably not what you want");
5247 already = 1;
5248 }
5249 }
5250 }
5251 \f
5252 /* Get the struct, enum or union (CODE says which) with tag NAME.
5253 Define the tag as a forward-reference if it is not defined. */
5254
5255 tree
5256 xref_tag (code, name)
5257 enum tree_code code;
5258 tree name;
5259 {
5260 /* If a cross reference is requested, look up the type
5261 already defined for this tag and return it. */
5262
5263 tree ref = lookup_tag (code, name, current_binding_level, 0);
5264 /* If this is the right type of tag, return what we found.
5265 (This reference will be shadowed by shadow_tag later if appropriate.)
5266 If this is the wrong type of tag, do not return it. If it was the
5267 wrong type in the same binding level, we will have had an error
5268 message already; if in a different binding level and declaring
5269 a name, pending_xref_error will give an error message; but if in a
5270 different binding level and not declaring a name, this tag should
5271 shadow the previous declaration of a different type of tag, and
5272 this would not work properly if we return the reference found.
5273 (For example, with "struct foo" in an outer scope, "union foo;"
5274 must shadow that tag with a new one of union type.) */
5275 if (ref && TREE_CODE (ref) == code)
5276 return ref;
5277
5278 /* If no such tag is yet defined, create a forward-reference node
5279 and record it as the "definition".
5280 When a real declaration of this type is found,
5281 the forward-reference will be altered into a real type. */
5282
5283 ref = make_node (code);
5284 if (code == ENUMERAL_TYPE)
5285 {
5286 /* Give the type a default layout like unsigned int
5287 to avoid crashing if it does not get defined. */
5288 TYPE_MODE (ref) = TYPE_MODE (unsigned_type_node);
5289 TYPE_ALIGN (ref) = TYPE_ALIGN (unsigned_type_node);
5290 TYPE_USER_ALIGN (ref) = 0;
5291 TREE_UNSIGNED (ref) = 1;
5292 TYPE_PRECISION (ref) = TYPE_PRECISION (unsigned_type_node);
5293 TYPE_MIN_VALUE (ref) = TYPE_MIN_VALUE (unsigned_type_node);
5294 TYPE_MAX_VALUE (ref) = TYPE_MAX_VALUE (unsigned_type_node);
5295 }
5296
5297 pushtag (name, ref);
5298
5299 return ref;
5300 }
5301 \f
5302 /* Make sure that the tag NAME is defined *in the current binding level*
5303 at least as a forward reference.
5304 CODE says which kind of tag NAME ought to be. */
5305
5306 tree
5307 start_struct (code, name)
5308 enum tree_code code;
5309 tree name;
5310 {
5311 /* If there is already a tag defined at this binding level
5312 (as a forward reference), just return it. */
5313
5314 tree ref = 0;
5315
5316 if (name != 0)
5317 ref = lookup_tag (code, name, current_binding_level, 1);
5318 if (ref && TREE_CODE (ref) == code)
5319 {
5320 C_TYPE_BEING_DEFINED (ref) = 1;
5321 TYPE_PACKED (ref) = flag_pack_struct;
5322 if (TYPE_FIELDS (ref))
5323 {
5324 if (code == UNION_TYPE)
5325 error ("redefinition of `union %s'",
5326 IDENTIFIER_POINTER (name));
5327 else
5328 error ("redefinition of `struct %s'",
5329 IDENTIFIER_POINTER (name));
5330 }
5331
5332 return ref;
5333 }
5334
5335 /* Otherwise create a forward-reference just so the tag is in scope. */
5336
5337 ref = make_node (code);
5338 pushtag (name, ref);
5339 C_TYPE_BEING_DEFINED (ref) = 1;
5340 TYPE_PACKED (ref) = flag_pack_struct;
5341 return ref;
5342 }
5343
5344 /* Process the specs, declarator (NULL if omitted) and width (NULL if omitted)
5345 of a structure component, returning a FIELD_DECL node.
5346 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node.
5347
5348 This is done during the parsing of the struct declaration.
5349 The FIELD_DECL nodes are chained together and the lot of them
5350 are ultimately passed to `build_struct' to make the RECORD_TYPE node. */
5351
5352 tree
5353 grokfield (filename, line, declarator, declspecs, width)
5354 const char *filename ATTRIBUTE_UNUSED;
5355 int line ATTRIBUTE_UNUSED;
5356 tree declarator, declspecs, width;
5357 {
5358 tree value;
5359
5360 if (declarator == NULL_TREE && width == NULL_TREE)
5361 {
5362 /* This is an unnamed decl. We only support unnamed
5363 structs/unions, so check for other things and refuse them. */
5364 if (TREE_CODE (TREE_VALUE (declspecs)) != RECORD_TYPE
5365 && TREE_CODE (TREE_VALUE (declspecs)) != UNION_TYPE)
5366 {
5367 error ("unnamed fields of type other than struct or union are not allowed");
5368 return NULL_TREE;
5369 }
5370 }
5371
5372 value = grokdeclarator (declarator, declspecs, width ? BITFIELD : FIELD, 0);
5373
5374 finish_decl (value, NULL_TREE, NULL_TREE);
5375 DECL_INITIAL (value) = width;
5376
5377 maybe_objc_check_decl (value);
5378 return value;
5379 }
5380 \f
5381 /* Fill in the fields of a RECORD_TYPE or UNION_TYPE node, T.
5382 FIELDLIST is a chain of FIELD_DECL nodes for the fields.
5383 ATTRIBUTES are attributes to be applied to the structure. */
5384
5385 tree
5386 finish_struct (t, fieldlist, attributes)
5387 tree t;
5388 tree fieldlist;
5389 tree attributes;
5390 {
5391 tree x;
5392 int toplevel = global_binding_level == current_binding_level;
5393 int saw_named_field;
5394
5395 /* If this type was previously laid out as a forward reference,
5396 make sure we lay it out again. */
5397
5398 TYPE_SIZE (t) = 0;
5399
5400 decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5401
5402 /* Nameless union parm types are useful as GCC extension. */
5403 if (! (TREE_CODE (t) == UNION_TYPE && TYPE_NAME (t) == 0) && !pedantic)
5404 /* Otherwise, warn about any struct or union def. in parmlist. */
5405 if (in_parm_level_p ())
5406 {
5407 if (pedantic)
5408 pedwarn ("%s defined inside parms",
5409 TREE_CODE (t) == UNION_TYPE ? _("union") : _("structure"));
5410 else
5411 warning ("%s defined inside parms",
5412 TREE_CODE (t) == UNION_TYPE ? _("union") : _("structure"));
5413 }
5414
5415 if (pedantic)
5416 {
5417 for (x = fieldlist; x; x = TREE_CHAIN (x))
5418 if (DECL_NAME (x) != 0)
5419 break;
5420
5421 if (x == 0)
5422 pedwarn ("%s has no %s",
5423 TREE_CODE (t) == UNION_TYPE ? _("union") : _("struct"),
5424 fieldlist ? _("named members") : _("members"));
5425 }
5426
5427 /* Install struct as DECL_CONTEXT of each field decl.
5428 Also process specified field sizes,m which is found in the DECL_INITIAL.
5429 Store 0 there, except for ": 0" fields (so we can find them
5430 and delete them, below). */
5431
5432 saw_named_field = 0;
5433 for (x = fieldlist; x; x = TREE_CHAIN (x))
5434 {
5435 DECL_CONTEXT (x) = t;
5436 DECL_PACKED (x) |= TYPE_PACKED (t);
5437
5438 /* If any field is const, the structure type is pseudo-const. */
5439 if (TREE_READONLY (x))
5440 C_TYPE_FIELDS_READONLY (t) = 1;
5441 else
5442 {
5443 /* A field that is pseudo-const makes the structure likewise. */
5444 tree t1 = TREE_TYPE (x);
5445 while (TREE_CODE (t1) == ARRAY_TYPE)
5446 t1 = TREE_TYPE (t1);
5447 if ((TREE_CODE (t1) == RECORD_TYPE || TREE_CODE (t1) == UNION_TYPE)
5448 && C_TYPE_FIELDS_READONLY (t1))
5449 C_TYPE_FIELDS_READONLY (t) = 1;
5450 }
5451
5452 /* Any field that is volatile means variables of this type must be
5453 treated in some ways as volatile. */
5454 if (TREE_THIS_VOLATILE (x))
5455 C_TYPE_FIELDS_VOLATILE (t) = 1;
5456
5457 /* Any field of nominal variable size implies structure is too. */
5458 if (C_DECL_VARIABLE_SIZE (x))
5459 C_TYPE_VARIABLE_SIZE (t) = 1;
5460
5461 /* Detect invalid nested redefinition. */
5462 if (TREE_TYPE (x) == t)
5463 error ("nested redefinition of `%s'",
5464 IDENTIFIER_POINTER (TYPE_NAME (t)));
5465
5466 /* Detect invalid bit-field size. */
5467 if (DECL_INITIAL (x))
5468 STRIP_NOPS (DECL_INITIAL (x));
5469 if (DECL_INITIAL (x))
5470 {
5471 if (TREE_CODE (DECL_INITIAL (x)) == INTEGER_CST)
5472 constant_expression_warning (DECL_INITIAL (x));
5473 else
5474 {
5475 error_with_decl (x,
5476 "bit-field `%s' width not an integer constant");
5477 DECL_INITIAL (x) = NULL;
5478 }
5479 }
5480
5481 /* Detect invalid bit-field type. */
5482 if (DECL_INITIAL (x)
5483 && TREE_CODE (TREE_TYPE (x)) != INTEGER_TYPE
5484 && TREE_CODE (TREE_TYPE (x)) != BOOLEAN_TYPE
5485 && TREE_CODE (TREE_TYPE (x)) != ENUMERAL_TYPE)
5486 {
5487 error_with_decl (x, "bit-field `%s' has invalid type");
5488 DECL_INITIAL (x) = NULL;
5489 }
5490
5491 if (DECL_INITIAL (x) && pedantic
5492 && TYPE_MAIN_VARIANT (TREE_TYPE (x)) != integer_type_node
5493 && TYPE_MAIN_VARIANT (TREE_TYPE (x)) != unsigned_type_node
5494 && TYPE_MAIN_VARIANT (TREE_TYPE (x)) != c_bool_type_node
5495 /* Accept an enum that's equivalent to int or unsigned int. */
5496 && !(TREE_CODE (TREE_TYPE (x)) == ENUMERAL_TYPE
5497 && (TYPE_PRECISION (TREE_TYPE (x))
5498 == TYPE_PRECISION (integer_type_node))))
5499 pedwarn_with_decl (x, "bit-field `%s' type invalid in ISO C");
5500
5501 /* Detect and ignore out of range field width and process valid
5502 field widths. */
5503 if (DECL_INITIAL (x))
5504 {
5505 int max_width
5506 = (TYPE_MAIN_VARIANT (TREE_TYPE (x)) == c_bool_type_node
5507 ? CHAR_TYPE_SIZE : TYPE_PRECISION (TREE_TYPE (x)));
5508
5509 if (tree_int_cst_sgn (DECL_INITIAL (x)) < 0)
5510 error_with_decl (x, "negative width in bit-field `%s'");
5511 else if (0 < compare_tree_int (DECL_INITIAL (x), max_width))
5512 pedwarn_with_decl (x, "width of `%s' exceeds its type");
5513 else if (integer_zerop (DECL_INITIAL (x)) && DECL_NAME (x) != 0)
5514 error_with_decl (x, "zero width for bit-field `%s'");
5515 else
5516 {
5517 /* The test above has assured us that TREE_INT_CST_HIGH is 0. */
5518 unsigned HOST_WIDE_INT width
5519 = tree_low_cst (DECL_INITIAL (x), 1);
5520
5521 if (TREE_CODE (TREE_TYPE (x)) == ENUMERAL_TYPE
5522 && (width < min_precision (TYPE_MIN_VALUE (TREE_TYPE (x)),
5523 TREE_UNSIGNED (TREE_TYPE (x)))
5524 || (width
5525 < min_precision (TYPE_MAX_VALUE (TREE_TYPE (x)),
5526 TREE_UNSIGNED (TREE_TYPE (x))))))
5527 warning_with_decl (x,
5528 "`%s' is narrower than values of its type");
5529
5530 DECL_SIZE (x) = bitsize_int (width);
5531 DECL_BIT_FIELD (x) = 1;
5532 SET_DECL_C_BIT_FIELD (x);
5533
5534 if (width == 0
5535 && ! (* targetm.ms_bitfield_layout_p) (t))
5536 {
5537 /* field size 0 => force desired amount of alignment. */
5538 #ifdef EMPTY_FIELD_BOUNDARY
5539 DECL_ALIGN (x) = MAX (DECL_ALIGN (x), EMPTY_FIELD_BOUNDARY);
5540 #endif
5541 #ifdef PCC_BITFIELD_TYPE_MATTERS
5542 if (PCC_BITFIELD_TYPE_MATTERS)
5543 {
5544 DECL_ALIGN (x) = MAX (DECL_ALIGN (x),
5545 TYPE_ALIGN (TREE_TYPE (x)));
5546 DECL_USER_ALIGN (x) |= TYPE_USER_ALIGN (TREE_TYPE (x));
5547 }
5548 #endif
5549 }
5550 }
5551 }
5552
5553 else if (TREE_TYPE (x) != error_mark_node)
5554 {
5555 unsigned int min_align = (DECL_PACKED (x) ? BITS_PER_UNIT
5556 : TYPE_ALIGN (TREE_TYPE (x)));
5557
5558 /* Non-bit-fields are aligned for their type, except packed
5559 fields which require only BITS_PER_UNIT alignment. */
5560 DECL_ALIGN (x) = MAX (DECL_ALIGN (x), min_align);
5561 if (! DECL_PACKED (x))
5562 DECL_USER_ALIGN (x) |= TYPE_USER_ALIGN (TREE_TYPE (x));
5563 }
5564
5565 DECL_INITIAL (x) = 0;
5566
5567 /* Detect flexible array member in an invalid context. */
5568 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
5569 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
5570 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
5571 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
5572 {
5573 if (TREE_CODE (t) == UNION_TYPE)
5574 error_with_decl (x, "flexible array member in union");
5575 else if (TREE_CHAIN (x) != NULL_TREE)
5576 error_with_decl (x, "flexible array member not at end of struct");
5577 else if (! saw_named_field)
5578 error_with_decl (x, "flexible array member in otherwise empty struct");
5579 }
5580 if (DECL_NAME (x))
5581 saw_named_field = 1;
5582 }
5583
5584 /* Delete all duplicate fields from the fieldlist */
5585 for (x = fieldlist; x && TREE_CHAIN (x);)
5586 /* Anonymous fields aren't duplicates. */
5587 if (DECL_NAME (TREE_CHAIN (x)) == 0)
5588 x = TREE_CHAIN (x);
5589 else
5590 {
5591 tree y = fieldlist;
5592
5593 while (1)
5594 {
5595 if (DECL_NAME (y) == DECL_NAME (TREE_CHAIN (x)))
5596 break;
5597 if (y == x)
5598 break;
5599 y = TREE_CHAIN (y);
5600 }
5601 if (DECL_NAME (y) == DECL_NAME (TREE_CHAIN (x)))
5602 {
5603 error_with_decl (TREE_CHAIN (x), "duplicate member `%s'");
5604 TREE_CHAIN (x) = TREE_CHAIN (TREE_CHAIN (x));
5605 }
5606 else
5607 x = TREE_CHAIN (x);
5608 }
5609
5610 /* Now we have the nearly final fieldlist. Record it,
5611 then lay out the structure or union (including the fields). */
5612
5613 TYPE_FIELDS (t) = fieldlist;
5614
5615 layout_type (t);
5616
5617 /* Delete all zero-width bit-fields from the fieldlist */
5618 {
5619 tree *fieldlistp = &fieldlist;
5620 while (*fieldlistp)
5621 if (TREE_CODE (*fieldlistp) == FIELD_DECL && DECL_INITIAL (*fieldlistp))
5622 *fieldlistp = TREE_CHAIN (*fieldlistp);
5623 else
5624 fieldlistp = &TREE_CHAIN (*fieldlistp);
5625 }
5626
5627 /* Now we have the truly final field list.
5628 Store it in this type and in the variants. */
5629
5630 TYPE_FIELDS (t) = fieldlist;
5631
5632 for (x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
5633 {
5634 TYPE_FIELDS (x) = TYPE_FIELDS (t);
5635 TYPE_LANG_SPECIFIC (x) = TYPE_LANG_SPECIFIC (t);
5636 TYPE_ALIGN (x) = TYPE_ALIGN (t);
5637 TYPE_USER_ALIGN (x) = TYPE_USER_ALIGN (t);
5638 }
5639
5640 /* If this was supposed to be a transparent union, but we can't
5641 make it one, warn and turn off the flag. */
5642 if (TREE_CODE (t) == UNION_TYPE
5643 && TYPE_TRANSPARENT_UNION (t)
5644 && TYPE_MODE (t) != DECL_MODE (TYPE_FIELDS (t)))
5645 {
5646 TYPE_TRANSPARENT_UNION (t) = 0;
5647 warning ("union cannot be made transparent");
5648 }
5649
5650 /* If this structure or union completes the type of any previous
5651 variable declaration, lay it out and output its rtl. */
5652
5653 if (current_binding_level->incomplete_list != NULL_TREE)
5654 {
5655 tree prev = NULL_TREE;
5656
5657 for (x = current_binding_level->incomplete_list; x; x = TREE_CHAIN (x))
5658 {
5659 tree decl = TREE_VALUE (x);
5660
5661 if (TYPE_MAIN_VARIANT (TREE_TYPE (decl)) == TYPE_MAIN_VARIANT (t)
5662 && TREE_CODE (decl) != TYPE_DECL)
5663 {
5664 layout_decl (decl, 0);
5665 /* This is a no-op in c-lang.c or something real in objc-actions.c. */
5666 maybe_objc_check_decl (decl);
5667 rest_of_decl_compilation (decl, NULL, toplevel, 0);
5668 if (! toplevel)
5669 expand_decl (decl);
5670 /* Unlink X from the incomplete list. */
5671 if (prev)
5672 TREE_CHAIN (prev) = TREE_CHAIN (x);
5673 else
5674 current_binding_level->incomplete_list = TREE_CHAIN (x);
5675 }
5676 else if (!COMPLETE_TYPE_P (TREE_TYPE (decl))
5677 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
5678 {
5679 tree element = TREE_TYPE (decl);
5680 while (TREE_CODE (element) == ARRAY_TYPE)
5681 element = TREE_TYPE (element);
5682 if (element == t)
5683 {
5684 layout_array_type (TREE_TYPE (decl));
5685 if (TREE_CODE (decl) != TYPE_DECL)
5686 {
5687 layout_decl (decl, 0);
5688 maybe_objc_check_decl (decl);
5689 rest_of_decl_compilation (decl, NULL, toplevel, 0);
5690 if (! toplevel)
5691 expand_decl (decl);
5692 }
5693 /* Unlink X from the incomplete list. */
5694 if (prev)
5695 TREE_CHAIN (prev) = TREE_CHAIN (x);
5696 else
5697 current_binding_level->incomplete_list = TREE_CHAIN (x);
5698 }
5699 }
5700 }
5701 }
5702
5703 /* Finish debugging output for this type. */
5704 rest_of_type_compilation (t, toplevel);
5705
5706 return t;
5707 }
5708
5709 /* Lay out the type T, and its element type, and so on. */
5710
5711 static void
5712 layout_array_type (t)
5713 tree t;
5714 {
5715 if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
5716 layout_array_type (TREE_TYPE (t));
5717 layout_type (t);
5718 }
5719 \f
5720 /* Begin compiling the definition of an enumeration type.
5721 NAME is its name (or null if anonymous).
5722 Returns the type object, as yet incomplete.
5723 Also records info about it so that build_enumerator
5724 may be used to declare the individual values as they are read. */
5725
5726 tree
5727 start_enum (name)
5728 tree name;
5729 {
5730 tree enumtype = 0;
5731
5732 /* If this is the real definition for a previous forward reference,
5733 fill in the contents in the same object that used to be the
5734 forward reference. */
5735
5736 if (name != 0)
5737 enumtype = lookup_tag (ENUMERAL_TYPE, name, current_binding_level, 1);
5738
5739 if (enumtype == 0 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
5740 {
5741 enumtype = make_node (ENUMERAL_TYPE);
5742 pushtag (name, enumtype);
5743 }
5744
5745 C_TYPE_BEING_DEFINED (enumtype) = 1;
5746
5747 if (TYPE_VALUES (enumtype) != 0)
5748 {
5749 /* This enum is a named one that has been declared already. */
5750 error ("redeclaration of `enum %s'", IDENTIFIER_POINTER (name));
5751
5752 /* Completely replace its old definition.
5753 The old enumerators remain defined, however. */
5754 TYPE_VALUES (enumtype) = 0;
5755 }
5756
5757 enum_next_value = integer_zero_node;
5758 enum_overflow = 0;
5759
5760 if (flag_short_enums)
5761 TYPE_PACKED (enumtype) = 1;
5762
5763 return enumtype;
5764 }
5765
5766 /* After processing and defining all the values of an enumeration type,
5767 install their decls in the enumeration type and finish it off.
5768 ENUMTYPE is the type object, VALUES a list of decl-value pairs,
5769 and ATTRIBUTES are the specified attributes.
5770 Returns ENUMTYPE. */
5771
5772 tree
5773 finish_enum (enumtype, values, attributes)
5774 tree enumtype;
5775 tree values;
5776 tree attributes;
5777 {
5778 tree pair, tem;
5779 tree minnode = 0, maxnode = 0, enum_value_type;
5780 int precision, unsign;
5781 int toplevel = (global_binding_level == current_binding_level);
5782
5783 if (in_parm_level_p ())
5784 warning ("enum defined inside parms");
5785
5786 decl_attributes (&enumtype, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5787
5788 /* Calculate the maximum value of any enumerator in this type. */
5789
5790 if (values == error_mark_node)
5791 minnode = maxnode = integer_zero_node;
5792 else
5793 {
5794 minnode = maxnode = TREE_VALUE (values);
5795 for (pair = TREE_CHAIN (values); pair; pair = TREE_CHAIN (pair))
5796 {
5797 tree value = TREE_VALUE (pair);
5798 if (tree_int_cst_lt (maxnode, value))
5799 maxnode = value;
5800 if (tree_int_cst_lt (value, minnode))
5801 minnode = value;
5802 }
5803 }
5804
5805 /* Construct the final type of this enumeration. It is the same
5806 as one of the integral types - the narrowest one that fits, except
5807 that normally we only go as narrow as int - and signed iff any of
5808 the values are negative. */
5809 unsign = (tree_int_cst_sgn (minnode) >= 0);
5810 precision = MAX (min_precision (minnode, unsign),
5811 min_precision (maxnode, unsign));
5812 if (TYPE_PACKED (enumtype) || precision > TYPE_PRECISION (integer_type_node))
5813 {
5814 tree narrowest = c_common_type_for_size (precision, unsign);
5815 if (narrowest == 0)
5816 {
5817 warning ("enumeration values exceed range of largest integer");
5818 narrowest = long_long_integer_type_node;
5819 }
5820
5821 precision = TYPE_PRECISION (narrowest);
5822 }
5823 else
5824 precision = TYPE_PRECISION (integer_type_node);
5825
5826 if (precision == TYPE_PRECISION (integer_type_node))
5827 enum_value_type = c_common_type_for_size (precision, 0);
5828 else
5829 enum_value_type = enumtype;
5830
5831 TYPE_MIN_VALUE (enumtype) = minnode;
5832 TYPE_MAX_VALUE (enumtype) = maxnode;
5833 TYPE_PRECISION (enumtype) = precision;
5834 TREE_UNSIGNED (enumtype) = unsign;
5835 TYPE_SIZE (enumtype) = 0;
5836 layout_type (enumtype);
5837
5838 if (values != error_mark_node)
5839 {
5840 /* Change the type of the enumerators to be the enum type. We
5841 need to do this irrespective of the size of the enum, for
5842 proper type checking. Replace the DECL_INITIALs of the
5843 enumerators, and the value slots of the list, with copies
5844 that have the enum type; they cannot be modified in place
5845 because they may be shared (e.g. integer_zero_node) Finally,
5846 change the purpose slots to point to the names of the decls. */
5847 for (pair = values; pair; pair = TREE_CHAIN (pair))
5848 {
5849 tree enu = TREE_PURPOSE (pair);
5850
5851 TREE_TYPE (enu) = enumtype;
5852 DECL_SIZE (enu) = TYPE_SIZE (enumtype);
5853 DECL_SIZE_UNIT (enu) = TYPE_SIZE_UNIT (enumtype);
5854 DECL_ALIGN (enu) = TYPE_ALIGN (enumtype);
5855 DECL_USER_ALIGN (enu) = TYPE_USER_ALIGN (enumtype);
5856 DECL_MODE (enu) = TYPE_MODE (enumtype);
5857
5858 /* The ISO C Standard mandates enumerators to have type int,
5859 even though the underlying type of an enum type is
5860 unspecified. Here we convert any enumerators that fit in
5861 an int to type int, to avoid promotions to unsigned types
5862 when comparing integers with enumerators that fit in the
5863 int range. When -pedantic is given, build_enumerator()
5864 would have already taken care of those that don't fit. */
5865 if (int_fits_type_p (DECL_INITIAL (enu), enum_value_type))
5866 DECL_INITIAL (enu) = convert (enum_value_type, DECL_INITIAL (enu));
5867 else
5868 DECL_INITIAL (enu) = convert (enumtype, DECL_INITIAL (enu));
5869
5870 TREE_PURPOSE (pair) = DECL_NAME (enu);
5871 TREE_VALUE (pair) = DECL_INITIAL (enu);
5872 }
5873
5874 TYPE_VALUES (enumtype) = values;
5875 }
5876
5877 /* Fix up all variant types of this enum type. */
5878 for (tem = TYPE_MAIN_VARIANT (enumtype); tem; tem = TYPE_NEXT_VARIANT (tem))
5879 {
5880 if (tem == enumtype)
5881 continue;
5882 TYPE_VALUES (tem) = TYPE_VALUES (enumtype);
5883 TYPE_MIN_VALUE (tem) = TYPE_MIN_VALUE (enumtype);
5884 TYPE_MAX_VALUE (tem) = TYPE_MAX_VALUE (enumtype);
5885 TYPE_SIZE (tem) = TYPE_SIZE (enumtype);
5886 TYPE_SIZE_UNIT (tem) = TYPE_SIZE_UNIT (enumtype);
5887 TYPE_MODE (tem) = TYPE_MODE (enumtype);
5888 TYPE_PRECISION (tem) = TYPE_PRECISION (enumtype);
5889 TYPE_ALIGN (tem) = TYPE_ALIGN (enumtype);
5890 TYPE_USER_ALIGN (tem) = TYPE_USER_ALIGN (enumtype);
5891 TREE_UNSIGNED (tem) = TREE_UNSIGNED (enumtype);
5892 }
5893
5894 /* Finish debugging output for this type. */
5895 rest_of_type_compilation (enumtype, toplevel);
5896
5897 return enumtype;
5898 }
5899
5900 /* Build and install a CONST_DECL for one value of the
5901 current enumeration type (one that was begun with start_enum).
5902 Return a tree-list containing the CONST_DECL and its value.
5903 Assignment of sequential values by default is handled here. */
5904
5905 tree
5906 build_enumerator (name, value)
5907 tree name, value;
5908 {
5909 tree decl, type;
5910
5911 /* Validate and default VALUE. */
5912
5913 /* Remove no-op casts from the value. */
5914 if (value)
5915 STRIP_TYPE_NOPS (value);
5916
5917 if (value != 0)
5918 {
5919 if (TREE_CODE (value) == INTEGER_CST)
5920 {
5921 value = default_conversion (value);
5922 constant_expression_warning (value);
5923 }
5924 else
5925 {
5926 error ("enumerator value for `%s' not integer constant",
5927 IDENTIFIER_POINTER (name));
5928 value = 0;
5929 }
5930 }
5931
5932 /* Default based on previous value. */
5933 /* It should no longer be possible to have NON_LVALUE_EXPR
5934 in the default. */
5935 if (value == 0)
5936 {
5937 value = enum_next_value;
5938 if (enum_overflow)
5939 error ("overflow in enumeration values");
5940 }
5941
5942 if (pedantic && ! int_fits_type_p (value, integer_type_node))
5943 {
5944 pedwarn ("ISO C restricts enumerator values to range of `int'");
5945 value = convert (integer_type_node, value);
5946 }
5947
5948 /* Set basis for default for next value. */
5949 enum_next_value = build_binary_op (PLUS_EXPR, value, integer_one_node, 0);
5950 enum_overflow = tree_int_cst_lt (enum_next_value, value);
5951
5952 /* Now create a declaration for the enum value name. */
5953
5954 type = TREE_TYPE (value);
5955 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
5956 TYPE_PRECISION (integer_type_node)),
5957 (TYPE_PRECISION (type)
5958 >= TYPE_PRECISION (integer_type_node)
5959 && TREE_UNSIGNED (type)));
5960
5961 decl = build_decl (CONST_DECL, name, type);
5962 DECL_INITIAL (decl) = convert (type, value);
5963 pushdecl (decl);
5964
5965 return tree_cons (decl, value, NULL_TREE);
5966 }
5967
5968 \f
5969 /* Create the FUNCTION_DECL for a function definition.
5970 DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of
5971 the declaration; they describe the function's name and the type it returns,
5972 but twisted together in a fashion that parallels the syntax of C.
5973
5974 This function creates a binding context for the function body
5975 as well as setting up the FUNCTION_DECL in current_function_decl.
5976
5977 Returns 1 on success. If the DECLARATOR is not suitable for a function
5978 (it defines a datum instead), we return 0, which tells
5979 yyparse to report a parse error. */
5980
5981 int
5982 start_function (declspecs, declarator, attributes)
5983 tree declarator, declspecs, attributes;
5984 {
5985 tree decl1, old_decl;
5986 tree restype;
5987 int old_immediate_size_expand = immediate_size_expand;
5988
5989 current_function_returns_value = 0; /* Assume, until we see it does. */
5990 current_function_returns_null = 0;
5991 current_function_returns_abnormally = 0;
5992 warn_about_return_type = 0;
5993 current_extern_inline = 0;
5994 c_function_varargs = 0;
5995 named_labels = 0;
5996 shadowed_labels = 0;
5997
5998 /* Don't expand any sizes in the return type of the function. */
5999 immediate_size_expand = 0;
6000
6001 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, 1);
6002
6003 /* If the declarator is not suitable for a function definition,
6004 cause a syntax error. */
6005 if (decl1 == 0)
6006 {
6007 immediate_size_expand = old_immediate_size_expand;
6008 return 0;
6009 }
6010
6011 decl_attributes (&decl1, attributes, 0);
6012
6013 /* If #pragma weak was used, mark the decl weak now. */
6014 if (current_binding_level == global_binding_level)
6015 maybe_apply_pragma_weak (decl1);
6016
6017 if (DECL_DECLARED_INLINE_P (decl1)
6018 && DECL_UNINLINABLE (decl1)
6019 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl1)))
6020 warning_with_decl (decl1,
6021 "inline function `%s' given attribute noinline");
6022
6023 announce_function (decl1);
6024
6025 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl1))))
6026 {
6027 error ("return type is an incomplete type");
6028 /* Make it return void instead. */
6029 TREE_TYPE (decl1)
6030 = build_function_type (void_type_node,
6031 TYPE_ARG_TYPES (TREE_TYPE (decl1)));
6032 }
6033
6034 if (warn_about_return_type)
6035 pedwarn_c99 ("return type defaults to `int'");
6036
6037 /* Save the parm names or decls from this function's declarator
6038 where store_parm_decls will find them. */
6039 current_function_parms = last_function_parms;
6040 current_function_parm_tags = last_function_parm_tags;
6041
6042 /* Make the init_value nonzero so pushdecl knows this is not tentative.
6043 error_mark_node is replaced below (in poplevel) with the BLOCK. */
6044 DECL_INITIAL (decl1) = error_mark_node;
6045
6046 /* If this definition isn't a prototype and we had a prototype declaration
6047 before, copy the arg type info from that prototype.
6048 But not if what we had before was a builtin function. */
6049 old_decl = lookup_name_current_level (DECL_NAME (decl1));
6050 if (old_decl != 0 && TREE_CODE (TREE_TYPE (old_decl)) == FUNCTION_TYPE
6051 && !DECL_BUILT_IN (old_decl)
6052 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
6053 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (old_decl))))
6054 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0)
6055 {
6056 TREE_TYPE (decl1) = TREE_TYPE (old_decl);
6057 current_function_prototype_file = DECL_SOURCE_FILE (old_decl);
6058 current_function_prototype_line = DECL_SOURCE_LINE (old_decl);
6059 }
6060
6061 /* If there is no explicit declaration, look for any out-of-scope implicit
6062 declarations. */
6063 if (old_decl == 0)
6064 old_decl = IDENTIFIER_IMPLICIT_DECL (DECL_NAME (decl1));
6065
6066 /* Optionally warn of old-fashioned def with no previous prototype. */
6067 if (warn_strict_prototypes
6068 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0
6069 && !(old_decl != 0
6070 && (TYPE_ARG_TYPES (TREE_TYPE (old_decl)) != 0
6071 || (DECL_BUILT_IN (old_decl)
6072 && ! C_DECL_ANTICIPATED (old_decl)))))
6073 warning ("function declaration isn't a prototype");
6074 /* Optionally warn of any global def with no previous prototype. */
6075 else if (warn_missing_prototypes
6076 && TREE_PUBLIC (decl1)
6077 && !(old_decl != 0
6078 && (TYPE_ARG_TYPES (TREE_TYPE (old_decl)) != 0
6079 || (DECL_BUILT_IN (old_decl)
6080 && ! C_DECL_ANTICIPATED (old_decl))))
6081 && ! MAIN_NAME_P (DECL_NAME (decl1)))
6082 warning_with_decl (decl1, "no previous prototype for `%s'");
6083 /* Optionally warn of any def with no previous prototype
6084 if the function has already been used. */
6085 else if (warn_missing_prototypes
6086 && old_decl != 0 && TREE_USED (old_decl)
6087 && TYPE_ARG_TYPES (TREE_TYPE (old_decl)) == 0)
6088 warning_with_decl (decl1,
6089 "`%s' was used with no prototype before its definition");
6090 /* Optionally warn of any global def with no previous declaration. */
6091 else if (warn_missing_declarations
6092 && TREE_PUBLIC (decl1)
6093 && old_decl == 0
6094 && ! MAIN_NAME_P (DECL_NAME (decl1)))
6095 warning_with_decl (decl1, "no previous declaration for `%s'");
6096 /* Optionally warn of any def with no previous declaration
6097 if the function has already been used. */
6098 else if (warn_missing_declarations
6099 && old_decl != 0 && TREE_USED (old_decl)
6100 && old_decl == IDENTIFIER_IMPLICIT_DECL (DECL_NAME (decl1)))
6101 warning_with_decl (decl1,
6102 "`%s' was used with no declaration before its definition");
6103
6104 /* This is a definition, not a reference.
6105 So normally clear DECL_EXTERNAL.
6106 However, `extern inline' acts like a declaration
6107 except for defining how to inline. So set DECL_EXTERNAL in that case. */
6108 DECL_EXTERNAL (decl1) = current_extern_inline;
6109
6110 /* This function exists in static storage.
6111 (This does not mean `static' in the C sense!) */
6112 TREE_STATIC (decl1) = 1;
6113
6114 /* A nested function is not global. */
6115 if (current_function_decl != 0)
6116 TREE_PUBLIC (decl1) = 0;
6117
6118 /* Warn for unlikely, improbable, or stupid declarations of `main'. */
6119 if (warn_main > 0 && MAIN_NAME_P (DECL_NAME (decl1)))
6120 {
6121 tree args;
6122 int argct = 0;
6123
6124 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
6125 != integer_type_node)
6126 pedwarn_with_decl (decl1, "return type of `%s' is not `int'");
6127
6128 for (args = TYPE_ARG_TYPES (TREE_TYPE (decl1)); args;
6129 args = TREE_CHAIN (args))
6130 {
6131 tree type = args ? TREE_VALUE (args) : 0;
6132
6133 if (type == void_type_node)
6134 break;
6135
6136 ++argct;
6137 switch (argct)
6138 {
6139 case 1:
6140 if (TYPE_MAIN_VARIANT (type) != integer_type_node)
6141 pedwarn_with_decl (decl1,
6142 "first argument of `%s' should be `int'");
6143 break;
6144
6145 case 2:
6146 if (TREE_CODE (type) != POINTER_TYPE
6147 || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
6148 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
6149 != char_type_node))
6150 pedwarn_with_decl (decl1,
6151 "second argument of `%s' should be `char **'");
6152 break;
6153
6154 case 3:
6155 if (TREE_CODE (type) != POINTER_TYPE
6156 || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
6157 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
6158 != char_type_node))
6159 pedwarn_with_decl (decl1,
6160 "third argument of `%s' should probably be `char **'");
6161 break;
6162 }
6163 }
6164
6165 /* It is intentional that this message does not mention the third
6166 argument because it's only mentioned in an appendix of the
6167 standard. */
6168 if (argct > 0 && (argct < 2 || argct > 3))
6169 pedwarn_with_decl (decl1, "`%s' takes only zero or two arguments");
6170
6171 if (! TREE_PUBLIC (decl1))
6172 pedwarn_with_decl (decl1, "`%s' is normally a non-static function");
6173 }
6174
6175 /* Record the decl so that the function name is defined.
6176 If we already have a decl for this name, and it is a FUNCTION_DECL,
6177 use the old decl. */
6178
6179 current_function_decl = pushdecl (decl1);
6180
6181 pushlevel (0);
6182 declare_parm_level (1);
6183 current_binding_level->subblocks_tag_transparent = 1;
6184
6185 make_decl_rtl (current_function_decl, NULL);
6186
6187 restype = TREE_TYPE (TREE_TYPE (current_function_decl));
6188 /* Promote the value to int before returning it. */
6189 if (c_promoting_integer_type_p (restype))
6190 {
6191 /* It retains unsignedness if not really getting wider. */
6192 if (TREE_UNSIGNED (restype)
6193 && (TYPE_PRECISION (restype)
6194 == TYPE_PRECISION (integer_type_node)))
6195 restype = unsigned_type_node;
6196 else
6197 restype = integer_type_node;
6198 }
6199 DECL_RESULT (current_function_decl)
6200 = build_decl (RESULT_DECL, NULL_TREE, restype);
6201
6202 /* If this fcn was already referenced via a block-scope `extern' decl
6203 (or an implicit decl), propagate certain information about the usage. */
6204 if (TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (current_function_decl)))
6205 TREE_ADDRESSABLE (current_function_decl) = 1;
6206
6207 immediate_size_expand = old_immediate_size_expand;
6208
6209 start_fname_decls ();
6210
6211 return 1;
6212 }
6213
6214 /* Record that this function is going to be a varargs function.
6215 This is called before store_parm_decls, which is too early
6216 to call mark_varargs directly. */
6217
6218 void
6219 c_mark_varargs ()
6220 {
6221 c_function_varargs = 1;
6222 }
6223 \f
6224 /* Store the parameter declarations into the current function declaration.
6225 This is called after parsing the parameter declarations, before
6226 digesting the body of the function.
6227
6228 For an old-style definition, modify the function's type
6229 to specify at least the number of arguments. */
6230
6231 void
6232 store_parm_decls ()
6233 {
6234 tree fndecl = current_function_decl;
6235 tree parm;
6236
6237 /* This is either a chain of PARM_DECLs (if a prototype was used)
6238 or a list of IDENTIFIER_NODEs (for an old-fashioned C definition). */
6239 tree specparms = current_function_parms;
6240
6241 /* This is a list of types declared among parms in a prototype. */
6242 tree parmtags = current_function_parm_tags;
6243
6244 /* This is a chain of PARM_DECLs from old-style parm declarations. */
6245 tree parmdecls = getdecls ();
6246
6247 /* This is a chain of any other decls that came in among the parm
6248 declarations. If a parm is declared with enum {foo, bar} x;
6249 then CONST_DECLs for foo and bar are put here. */
6250 tree nonparms = 0;
6251
6252 /* The function containing FNDECL, if any. */
6253 tree context = decl_function_context (fndecl);
6254
6255 /* Nonzero if this definition is written with a prototype. */
6256 int prototype = 0;
6257
6258 int saved_warn_shadow = warn_shadow;
6259
6260 /* Don't re-emit shadow warnings. */
6261 warn_shadow = 0;
6262
6263 if (specparms != 0 && TREE_CODE (specparms) != TREE_LIST)
6264 {
6265 /* This case is when the function was defined with an ANSI prototype.
6266 The parms already have decls, so we need not do anything here
6267 except record them as in effect
6268 and complain if any redundant old-style parm decls were written. */
6269
6270 tree next;
6271 tree others = 0;
6272
6273 prototype = 1;
6274
6275 if (parmdecls != 0)
6276 {
6277 tree decl, link;
6278
6279 error_with_decl (fndecl,
6280 "parm types given both in parmlist and separately");
6281 /* Get rid of the erroneous decls; don't keep them on
6282 the list of parms, since they might not be PARM_DECLs. */
6283 for (decl = current_binding_level->names;
6284 decl; decl = TREE_CHAIN (decl))
6285 if (DECL_NAME (decl))
6286 IDENTIFIER_LOCAL_VALUE (DECL_NAME (decl)) = 0;
6287 for (link = current_binding_level->shadowed;
6288 link; link = TREE_CHAIN (link))
6289 IDENTIFIER_LOCAL_VALUE (TREE_PURPOSE (link)) = TREE_VALUE (link);
6290 current_binding_level->names = 0;
6291 current_binding_level->shadowed = 0;
6292 }
6293
6294 specparms = nreverse (specparms);
6295 for (parm = specparms; parm; parm = next)
6296 {
6297 next = TREE_CHAIN (parm);
6298 if (TREE_CODE (parm) == PARM_DECL)
6299 {
6300 if (DECL_NAME (parm) == 0)
6301 error_with_decl (parm, "parameter name omitted");
6302 else if (TREE_CODE (TREE_TYPE (parm)) != ERROR_MARK
6303 && VOID_TYPE_P (TREE_TYPE (parm)))
6304 {
6305 error_with_decl (parm, "parameter `%s' declared void");
6306 /* Change the type to error_mark_node so this parameter
6307 will be ignored by assign_parms. */
6308 TREE_TYPE (parm) = error_mark_node;
6309 }
6310 pushdecl (parm);
6311 }
6312 else
6313 {
6314 /* If we find an enum constant or a type tag,
6315 put it aside for the moment. */
6316 TREE_CHAIN (parm) = 0;
6317 others = chainon (others, parm);
6318 }
6319 }
6320
6321 /* Get the decls in their original chain order
6322 and record in the function. */
6323 DECL_ARGUMENTS (fndecl) = getdecls ();
6324
6325 #if 0
6326 /* If this function takes a variable number of arguments,
6327 add a phony parameter to the end of the parm list,
6328 to represent the position of the first unnamed argument. */
6329 if (TREE_VALUE (tree_last (TYPE_ARG_TYPES (TREE_TYPE (fndecl))))
6330 != void_type_node)
6331 {
6332 tree dummy = build_decl (PARM_DECL, NULL_TREE, void_type_node);
6333 /* Let's hope the address of the unnamed parm
6334 won't depend on its type. */
6335 TREE_TYPE (dummy) = integer_type_node;
6336 DECL_ARG_TYPE (dummy) = integer_type_node;
6337 DECL_ARGUMENTS (fndecl) = chainon (DECL_ARGUMENTS (fndecl), dummy);
6338 }
6339 #endif
6340
6341 /* Now pushdecl the enum constants. */
6342 for (parm = others; parm; parm = next)
6343 {
6344 next = TREE_CHAIN (parm);
6345 if (DECL_NAME (parm) == 0)
6346 ;
6347 else if (TYPE_MAIN_VARIANT (TREE_TYPE (parm)) == void_type_node)
6348 ;
6349 else if (TREE_CODE (parm) != PARM_DECL)
6350 pushdecl (parm);
6351 }
6352
6353 storetags (chainon (parmtags, gettags ()));
6354 }
6355 else
6356 {
6357 /* SPECPARMS is an identifier list--a chain of TREE_LIST nodes
6358 each with a parm name as the TREE_VALUE.
6359
6360 PARMDECLS is a chain of declarations for parameters.
6361 Warning! It can also contain CONST_DECLs which are not parameters
6362 but are names of enumerators of any enum types
6363 declared among the parameters.
6364
6365 First match each formal parameter name with its declaration.
6366 Associate decls with the names and store the decls
6367 into the TREE_PURPOSE slots. */
6368
6369 /* We use DECL_WEAK as a flag to show which parameters have been
6370 seen already since it is not used on PARM_DECL or CONST_DECL. */
6371 for (parm = parmdecls; parm; parm = TREE_CHAIN (parm))
6372 DECL_WEAK (parm) = 0;
6373
6374 for (parm = specparms; parm; parm = TREE_CHAIN (parm))
6375 {
6376 tree tail, found = NULL;
6377
6378 if (TREE_VALUE (parm) == 0)
6379 {
6380 error_with_decl (fndecl,
6381 "parameter name missing from parameter list");
6382 TREE_PURPOSE (parm) = 0;
6383 continue;
6384 }
6385
6386 /* See if any of the parmdecls specifies this parm by name.
6387 Ignore any enumerator decls. */
6388 for (tail = parmdecls; tail; tail = TREE_CHAIN (tail))
6389 if (DECL_NAME (tail) == TREE_VALUE (parm)
6390 && TREE_CODE (tail) == PARM_DECL)
6391 {
6392 found = tail;
6393 break;
6394 }
6395
6396 /* If declaration already marked, we have a duplicate name.
6397 Complain, and don't use this decl twice. */
6398 if (found && DECL_WEAK (found))
6399 {
6400 error_with_decl (found, "multiple parameters named `%s'");
6401 found = 0;
6402 }
6403
6404 /* If the declaration says "void", complain and ignore it. */
6405 if (found && VOID_TYPE_P (TREE_TYPE (found)))
6406 {
6407 error_with_decl (found, "parameter `%s' declared void");
6408 TREE_TYPE (found) = integer_type_node;
6409 DECL_ARG_TYPE (found) = integer_type_node;
6410 layout_decl (found, 0);
6411 }
6412
6413 /* If no declaration found, default to int. */
6414 if (!found)
6415 {
6416 found = build_decl (PARM_DECL, TREE_VALUE (parm),
6417 integer_type_node);
6418 DECL_ARG_TYPE (found) = TREE_TYPE (found);
6419 DECL_SOURCE_LINE (found) = DECL_SOURCE_LINE (fndecl);
6420 DECL_SOURCE_FILE (found) = DECL_SOURCE_FILE (fndecl);
6421 if (flag_isoc99)
6422 pedwarn_with_decl (found, "type of `%s' defaults to `int'");
6423 else if (extra_warnings)
6424 warning_with_decl (found, "type of `%s' defaults to `int'");
6425 pushdecl (found);
6426 }
6427
6428 TREE_PURPOSE (parm) = found;
6429
6430 /* Mark this decl as "already found". */
6431 DECL_WEAK (found) = 1;
6432 }
6433
6434 /* Put anything which is on the parmdecls chain and which is
6435 not a PARM_DECL onto the list NONPARMS. (The types of
6436 non-parm things which might appear on the list include
6437 enumerators and NULL-named TYPE_DECL nodes.) Complain about
6438 any actual PARM_DECLs not matched with any names. */
6439
6440 nonparms = 0;
6441 for (parm = parmdecls; parm;)
6442 {
6443 tree next = TREE_CHAIN (parm);
6444 TREE_CHAIN (parm) = 0;
6445
6446 if (TREE_CODE (parm) != PARM_DECL)
6447 nonparms = chainon (nonparms, parm);
6448 else
6449 {
6450 /* Complain about args with incomplete types. */
6451 if (!COMPLETE_TYPE_P (TREE_TYPE (parm)))
6452 {
6453 error_with_decl (parm, "parameter `%s' has incomplete type");
6454 TREE_TYPE (parm) = error_mark_node;
6455 }
6456
6457 if (! DECL_WEAK (parm))
6458 {
6459 error_with_decl (parm,
6460 "declaration for parameter `%s' but no such parameter");
6461 /* Pretend the parameter was not missing.
6462 This gets us to a standard state and minimizes
6463 further error messages. */
6464 specparms
6465 = chainon (specparms,
6466 tree_cons (parm, NULL_TREE, NULL_TREE));
6467 }
6468 }
6469
6470 parm = next;
6471 }
6472
6473 /* Chain the declarations together in the order of the list of
6474 names. Store that chain in the function decl, replacing the
6475 list of names. */
6476 parm = specparms;
6477 DECL_ARGUMENTS (fndecl) = 0;
6478 {
6479 tree last;
6480 for (last = 0; parm; parm = TREE_CHAIN (parm))
6481 if (TREE_PURPOSE (parm))
6482 {
6483 if (last == 0)
6484 DECL_ARGUMENTS (fndecl) = TREE_PURPOSE (parm);
6485 else
6486 TREE_CHAIN (last) = TREE_PURPOSE (parm);
6487 last = TREE_PURPOSE (parm);
6488 TREE_CHAIN (last) = 0;
6489 }
6490 }
6491
6492 /* If there was a previous prototype,
6493 set the DECL_ARG_TYPE of each argument according to
6494 the type previously specified, and report any mismatches. */
6495
6496 if (TYPE_ARG_TYPES (TREE_TYPE (fndecl)))
6497 {
6498 tree type;
6499 for (parm = DECL_ARGUMENTS (fndecl),
6500 type = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
6501 parm || (type && (TYPE_MAIN_VARIANT (TREE_VALUE (type))
6502 != void_type_node));
6503 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
6504 {
6505 if (parm == 0 || type == 0
6506 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
6507 {
6508 error ("number of arguments doesn't match prototype");
6509 error_with_file_and_line (current_function_prototype_file,
6510 current_function_prototype_line,
6511 "prototype declaration");
6512 break;
6513 }
6514 /* Type for passing arg must be consistent with that
6515 declared for the arg. ISO C says we take the unqualified
6516 type for parameters declared with qualified type. */
6517 if (! comptypes (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (parm)),
6518 TYPE_MAIN_VARIANT (TREE_VALUE (type))))
6519 {
6520 if (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
6521 == TYPE_MAIN_VARIANT (TREE_VALUE (type)))
6522 {
6523 /* Adjust argument to match prototype. E.g. a previous
6524 `int foo(float);' prototype causes
6525 `int foo(x) float x; {...}' to be treated like
6526 `int foo(float x) {...}'. This is particularly
6527 useful for argument types like uid_t. */
6528 DECL_ARG_TYPE (parm) = TREE_TYPE (parm);
6529
6530 if (PROMOTE_PROTOTYPES
6531 && INTEGRAL_TYPE_P (TREE_TYPE (parm))
6532 && TYPE_PRECISION (TREE_TYPE (parm))
6533 < TYPE_PRECISION (integer_type_node))
6534 DECL_ARG_TYPE (parm) = integer_type_node;
6535
6536 if (pedantic)
6537 {
6538 pedwarn ("promoted argument `%s' doesn't match prototype",
6539 IDENTIFIER_POINTER (DECL_NAME (parm)));
6540 warning_with_file_and_line
6541 (current_function_prototype_file,
6542 current_function_prototype_line,
6543 "prototype declaration");
6544 }
6545 }
6546 else
6547 {
6548 error ("argument `%s' doesn't match prototype",
6549 IDENTIFIER_POINTER (DECL_NAME (parm)));
6550 error_with_file_and_line (current_function_prototype_file,
6551 current_function_prototype_line,
6552 "prototype declaration");
6553 }
6554 }
6555 }
6556 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = 0;
6557 }
6558
6559 /* Otherwise, create a prototype that would match. */
6560
6561 else
6562 {
6563 tree actual = 0, last = 0, type;
6564
6565 for (parm = DECL_ARGUMENTS (fndecl); parm; parm = TREE_CHAIN (parm))
6566 {
6567 type = tree_cons (NULL_TREE, DECL_ARG_TYPE (parm), NULL_TREE);
6568 if (last)
6569 TREE_CHAIN (last) = type;
6570 else
6571 actual = type;
6572 last = type;
6573 }
6574 type = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
6575 if (last)
6576 TREE_CHAIN (last) = type;
6577 else
6578 actual = type;
6579
6580 /* We are going to assign a new value for the TYPE_ACTUAL_ARG_TYPES
6581 of the type of this function, but we need to avoid having this
6582 affect the types of other similarly-typed functions, so we must
6583 first force the generation of an identical (but separate) type
6584 node for the relevant function type. The new node we create
6585 will be a variant of the main variant of the original function
6586 type. */
6587
6588 TREE_TYPE (fndecl) = build_type_copy (TREE_TYPE (fndecl));
6589
6590 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = actual;
6591 }
6592
6593 /* Now store the final chain of decls for the arguments
6594 as the decl-chain of the current lexical scope.
6595 Put the enumerators in as well, at the front so that
6596 DECL_ARGUMENTS is not modified. */
6597
6598 storedecls (chainon (nonparms, DECL_ARGUMENTS (fndecl)));
6599 }
6600
6601 /* Make sure the binding level for the top of the function body
6602 gets a BLOCK if there are any in the function.
6603 Otherwise, the dbx output is wrong. */
6604
6605 keep_next_if_subblocks = 1;
6606
6607 /* ??? This might be an improvement,
6608 but needs to be thought about some more. */
6609 #if 0
6610 keep_next_level_flag = 1;
6611 #endif
6612
6613 /* Write a record describing this function definition to the prototypes
6614 file (if requested). */
6615
6616 gen_aux_info_record (fndecl, 1, 0, prototype);
6617
6618 /* Initialize the RTL code for the function. */
6619 init_function_start (fndecl, input_filename, lineno);
6620
6621 /* Begin the statement tree for this function. */
6622 begin_stmt_tree (&DECL_SAVED_TREE (current_function_decl));
6623
6624 /* If this is a nested function, save away the sizes of any
6625 variable-size types so that we can expand them when generating
6626 RTL. */
6627 if (context)
6628 {
6629 tree t;
6630
6631 DECL_LANG_SPECIFIC (fndecl)->pending_sizes
6632 = nreverse (get_pending_sizes ());
6633 for (t = DECL_LANG_SPECIFIC (fndecl)->pending_sizes;
6634 t;
6635 t = TREE_CHAIN (t))
6636 SAVE_EXPR_CONTEXT (TREE_VALUE (t)) = context;
6637 }
6638
6639 /* This function is being processed in whole-function mode. */
6640 cfun->x_whole_function_mode_p = 1;
6641
6642 /* Even though we're inside a function body, we still don't want to
6643 call expand_expr to calculate the size of a variable-sized array.
6644 We haven't necessarily assigned RTL to all variables yet, so it's
6645 not safe to try to expand expressions involving them. */
6646 immediate_size_expand = 0;
6647 cfun->x_dont_save_pending_sizes_p = 1;
6648
6649 warn_shadow = saved_warn_shadow;
6650 }
6651 \f
6652 /* Finish up a function declaration and compile that function
6653 all the way to assembler language output. The free the storage
6654 for the function definition.
6655
6656 This is called after parsing the body of the function definition.
6657
6658 NESTED is nonzero if the function being finished is nested in another.
6659 CAN_DEFER_P is nonzero if the function may be deferred. */
6660
6661 void
6662 finish_function (nested, can_defer_p)
6663 int nested;
6664 int can_defer_p;
6665 {
6666 tree fndecl = current_function_decl;
6667
6668 #if 0
6669 /* This caused &foo to be of type ptr-to-const-function which then
6670 got a warning when stored in a ptr-to-function variable. */
6671 TREE_READONLY (fndecl) = 1;
6672 #endif
6673
6674 poplevel (1, 0, 1);
6675 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
6676
6677 /* Must mark the RESULT_DECL as being in this function. */
6678
6679 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
6680
6681 if (MAIN_NAME_P (DECL_NAME (fndecl)) && flag_hosted)
6682 {
6683 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (fndecl)))
6684 != integer_type_node)
6685 {
6686 /* If warn_main is 1 (-Wmain) or 2 (-Wall), we have already warned.
6687 If warn_main is -1 (-Wno-main) we don't want to be warned. */
6688 if (! warn_main)
6689 pedwarn_with_decl (fndecl, "return type of `%s' is not `int'");
6690 }
6691 else
6692 {
6693 #ifdef DEFAULT_MAIN_RETURN
6694 /* Make it so that `main' always returns success by default. */
6695 DEFAULT_MAIN_RETURN;
6696 #else
6697 if (flag_isoc99)
6698 c_expand_return (integer_zero_node);
6699 #endif
6700 }
6701 }
6702
6703 finish_fname_decls ();
6704
6705 /* Tie off the statement tree for this function. */
6706 finish_stmt_tree (&DECL_SAVED_TREE (fndecl));
6707
6708 /* Complain if there's just no return statement. */
6709 if (warn_return_type
6710 && TREE_CODE (TREE_TYPE (TREE_TYPE (fndecl))) != VOID_TYPE
6711 && !current_function_returns_value && !current_function_returns_null
6712 /* Don't complain if we abort. */
6713 && !current_function_returns_abnormally
6714 /* Don't warn for main(). */
6715 && !MAIN_NAME_P (DECL_NAME (fndecl))
6716 /* Or if they didn't actually specify a return type. */
6717 && !C_FUNCTION_IMPLICIT_INT (fndecl)
6718 /* Normally, with -Wreturn-type, flow will complain. Unless we're an
6719 inline function, as we might never be compiled separately. */
6720 && DECL_INLINE (fndecl))
6721 warning ("no return statement in function returning non-void");
6722
6723 /* Clear out memory we no longer need. */
6724 free_after_parsing (cfun);
6725 /* Since we never call rest_of_compilation, we never clear
6726 CFUN. Do so explicitly. */
6727 free_after_compilation (cfun);
6728 cfun = NULL;
6729
6730 if (! nested)
6731 {
6732 /* Generate RTL for the body of this function. */
6733 c_expand_body (fndecl, nested, can_defer_p);
6734
6735 /* Let the error reporting routines know that we're outside a
6736 function. For a nested function, this value is used in
6737 c_pop_function_context and then reset via pop_function_context. */
6738 current_function_decl = NULL;
6739 }
6740 }
6741
6742 /* Generate the RTL for a deferred function FNDECL. */
6743
6744 void
6745 c_expand_deferred_function (fndecl)
6746 tree fndecl;
6747 {
6748 /* DECL_INLINE or DECL_RESULT might got cleared after the inline
6749 function was deferred, e.g. in duplicate_decls. */
6750 if (DECL_INLINE (fndecl) && DECL_RESULT (fndecl))
6751 {
6752 c_expand_body (fndecl, 0, 0);
6753 current_function_decl = NULL;
6754 }
6755 }
6756
6757 /* Generate the RTL for the body of FNDECL. If NESTED_P is non-zero,
6758 then we are already in the process of generating RTL for another
6759 function. If can_defer_p is zero, we won't attempt to defer the
6760 generation of RTL. */
6761
6762 static void
6763 c_expand_body (fndecl, nested_p, can_defer_p)
6764 tree fndecl;
6765 int nested_p, can_defer_p;
6766 {
6767 int uninlinable = 1;
6768
6769 /* There's no reason to do any of the work here if we're only doing
6770 semantic analysis; this code just generates RTL. */
6771 if (flag_syntax_only)
6772 return;
6773
6774 if (flag_inline_trees)
6775 {
6776 /* First, cache whether the current function is inlinable. Some
6777 predicates depend on cfun and current_function_decl to
6778 function completely. */
6779 timevar_push (TV_INTEGRATION);
6780 uninlinable = ! tree_inlinable_function_p (fndecl);
6781
6782 if (! uninlinable && can_defer_p
6783 /* Save function tree for inlining. Should return 0 if the
6784 language does not support function deferring or the
6785 function could not be deferred. */
6786 && defer_fn (fndecl))
6787 {
6788 /* Let the back-end know that this function exists. */
6789 (*debug_hooks->deferred_inline_function) (fndecl);
6790 timevar_pop (TV_INTEGRATION);
6791 return;
6792 }
6793
6794 /* Then, inline any functions called in it. */
6795 optimize_inline_calls (fndecl);
6796 timevar_pop (TV_INTEGRATION);
6797 }
6798
6799 timevar_push (TV_EXPAND);
6800
6801 if (nested_p)
6802 {
6803 /* Make sure that we will evaluate variable-sized types involved
6804 in our function's type. */
6805 expand_pending_sizes (DECL_LANG_SPECIFIC (fndecl)->pending_sizes);
6806 /* Squirrel away our current state. */
6807 push_function_context ();
6808 }
6809
6810 /* Initialize the RTL code for the function. */
6811 current_function_decl = fndecl;
6812 input_filename = DECL_SOURCE_FILE (fndecl);
6813 init_function_start (fndecl, input_filename, DECL_SOURCE_LINE (fndecl));
6814
6815 /* This function is being processed in whole-function mode. */
6816 cfun->x_whole_function_mode_p = 1;
6817
6818 /* Even though we're inside a function body, we still don't want to
6819 call expand_expr to calculate the size of a variable-sized array.
6820 We haven't necessarily assigned RTL to all variables yet, so it's
6821 not safe to try to expand expressions involving them. */
6822 immediate_size_expand = 0;
6823 cfun->x_dont_save_pending_sizes_p = 1;
6824
6825 /* If this is a varargs function, inform function.c. */
6826 if (c_function_varargs)
6827 mark_varargs ();
6828
6829 /* Set up parameters and prepare for return, for the function. */
6830 expand_function_start (fndecl, 0);
6831
6832 /* If this function is `main', emit a call to `__main'
6833 to run global initializers, etc. */
6834 if (DECL_NAME (fndecl)
6835 && MAIN_NAME_P (DECL_NAME (fndecl))
6836 && DECL_CONTEXT (fndecl) == NULL_TREE)
6837 expand_main_function ();
6838
6839 /* Generate the RTL for this function. */
6840 expand_stmt (DECL_SAVED_TREE (fndecl));
6841 if (uninlinable)
6842 {
6843 /* Allow the body of the function to be garbage collected. */
6844 DECL_SAVED_TREE (fndecl) = NULL_TREE;
6845 }
6846
6847 /* We hard-wired immediate_size_expand to zero above.
6848 expand_function_end will decrement this variable. So, we set the
6849 variable to one here, so that after the decrement it will remain
6850 zero. */
6851 immediate_size_expand = 1;
6852
6853 /* Allow language dialects to perform special processing. */
6854 if (lang_expand_function_end)
6855 (*lang_expand_function_end) ();
6856
6857 /* Generate rtl for function exit. */
6858 expand_function_end (input_filename, lineno, 0);
6859
6860 /* If this is a nested function, protect the local variables in the stack
6861 above us from being collected while we're compiling this function. */
6862 if (nested_p)
6863 ggc_push_context ();
6864
6865 /* Run the optimizers and output the assembler code for this function. */
6866 rest_of_compilation (fndecl);
6867
6868 /* Undo the GC context switch. */
6869 if (nested_p)
6870 ggc_pop_context ();
6871
6872 /* With just -W, complain only if function returns both with
6873 and without a value. */
6874 if (extra_warnings
6875 && current_function_returns_value
6876 && current_function_returns_null)
6877 warning ("this function may return with or without a value");
6878
6879 /* If requested, warn about function definitions where the function will
6880 return a value (usually of some struct or union type) which itself will
6881 take up a lot of stack space. */
6882
6883 if (warn_larger_than && !DECL_EXTERNAL (fndecl) && TREE_TYPE (fndecl))
6884 {
6885 tree ret_type = TREE_TYPE (TREE_TYPE (fndecl));
6886
6887 if (ret_type && TYPE_SIZE_UNIT (ret_type)
6888 && TREE_CODE (TYPE_SIZE_UNIT (ret_type)) == INTEGER_CST
6889 && 0 < compare_tree_int (TYPE_SIZE_UNIT (ret_type),
6890 larger_than_size))
6891 {
6892 unsigned int size_as_int
6893 = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (ret_type));
6894
6895 if (compare_tree_int (TYPE_SIZE_UNIT (ret_type), size_as_int) == 0)
6896 warning_with_decl (fndecl,
6897 "size of return value of `%s' is %u bytes",
6898 size_as_int);
6899 else
6900 warning_with_decl (fndecl,
6901 "size of return value of `%s' is larger than %d bytes",
6902 larger_than_size);
6903 }
6904 }
6905
6906 if (DECL_SAVED_INSNS (fndecl) == 0 && ! nested_p
6907 && ! flag_inline_trees)
6908 {
6909 /* Stop pointing to the local nodes about to be freed.
6910 But DECL_INITIAL must remain nonzero so we know this
6911 was an actual function definition.
6912 For a nested function, this is done in c_pop_function_context.
6913 If rest_of_compilation set this to 0, leave it 0. */
6914 if (DECL_INITIAL (fndecl) != 0)
6915 DECL_INITIAL (fndecl) = error_mark_node;
6916
6917 DECL_ARGUMENTS (fndecl) = 0;
6918 }
6919
6920 if (DECL_STATIC_CONSTRUCTOR (fndecl))
6921 {
6922 if (targetm.have_ctors_dtors)
6923 (* targetm.asm_out.constructor) (XEXP (DECL_RTL (fndecl), 0),
6924 DEFAULT_INIT_PRIORITY);
6925 else
6926 static_ctors = tree_cons (NULL_TREE, fndecl, static_ctors);
6927 }
6928
6929 if (DECL_STATIC_DESTRUCTOR (fndecl))
6930 {
6931 if (targetm.have_ctors_dtors)
6932 (* targetm.asm_out.destructor) (XEXP (DECL_RTL (fndecl), 0),
6933 DEFAULT_INIT_PRIORITY);
6934 else
6935 static_dtors = tree_cons (NULL_TREE, fndecl, static_dtors);
6936 }
6937
6938 if (nested_p)
6939 /* Return to the enclosing function. */
6940 pop_function_context ();
6941 timevar_pop (TV_EXPAND);
6942 }
6943 \f
6944 /* Check the declarations given in a for-loop for satisfying the C99
6945 constraints. */
6946 void
6947 check_for_loop_decls ()
6948 {
6949 tree t;
6950
6951 if (!flag_isoc99)
6952 {
6953 /* If we get here, declarations have been used in a for loop without
6954 the C99 for loop scope. This doesn't make much sense, so don't
6955 allow it. */
6956 error ("`for' loop initial declaration used outside C99 mode");
6957 return;
6958 }
6959 /* C99 subclause 6.8.5 paragraph 3:
6960
6961 [#3] The declaration part of a for statement shall only
6962 declare identifiers for objects having storage class auto or
6963 register.
6964
6965 It isn't clear whether, in this sentence, "identifiers" binds to
6966 "shall only declare" or to "objects" - that is, whether all identifiers
6967 declared must be identifiers for objects, or whether the restriction
6968 only applies to those that are. (A question on this in comp.std.c
6969 in November 2000 received no answer.) We implement the strictest
6970 interpretation, to avoid creating an extension which later causes
6971 problems. */
6972
6973 for (t = gettags (); t; t = TREE_CHAIN (t))
6974 {
6975 if (TREE_PURPOSE (t) != 0)
6976 {
6977 enum tree_code code = TREE_CODE (TREE_VALUE (t));
6978
6979 if (code == RECORD_TYPE)
6980 error ("`struct %s' declared in `for' loop initial declaration",
6981 IDENTIFIER_POINTER (TREE_PURPOSE (t)));
6982 else if (code == UNION_TYPE)
6983 error ("`union %s' declared in `for' loop initial declaration",
6984 IDENTIFIER_POINTER (TREE_PURPOSE (t)));
6985 else
6986 error ("`enum %s' declared in `for' loop initial declaration",
6987 IDENTIFIER_POINTER (TREE_PURPOSE (t)));
6988 }
6989 }
6990
6991 for (t = getdecls (); t; t = TREE_CHAIN (t))
6992 {
6993 if (TREE_CODE (t) != VAR_DECL && DECL_NAME (t))
6994 error_with_decl (t, "declaration of non-variable `%s' in `for' loop initial declaration");
6995 else if (TREE_STATIC (t))
6996 error_with_decl (t, "declaration of static variable `%s' in `for' loop initial declaration");
6997 else if (DECL_EXTERNAL (t))
6998 error_with_decl (t, "declaration of `extern' variable `%s' in `for' loop initial declaration");
6999 }
7000 }
7001 \f
7002 /* Save and restore the variables in this file and elsewhere
7003 that keep track of the progress of compilation of the current function.
7004 Used for nested functions. */
7005
7006 struct language_function GTY(())
7007 {
7008 struct c_language_function base;
7009 tree named_labels;
7010 tree shadowed_labels;
7011 int returns_value;
7012 int returns_null;
7013 int returns_abnormally;
7014 int warn_about_return_type;
7015 int extern_inline;
7016 struct binding_level *binding_level;
7017 };
7018
7019 /* Save and reinitialize the variables
7020 used during compilation of a C function. */
7021
7022 void
7023 c_push_function_context (f)
7024 struct function *f;
7025 {
7026 struct language_function *p;
7027 p = ((struct language_function *)
7028 ggc_alloc (sizeof (struct language_function)));
7029 f->language = p;
7030
7031 p->base.x_stmt_tree = c_stmt_tree;
7032 p->base.x_scope_stmt_stack = c_scope_stmt_stack;
7033 p->named_labels = named_labels;
7034 p->shadowed_labels = shadowed_labels;
7035 p->returns_value = current_function_returns_value;
7036 p->returns_null = current_function_returns_null;
7037 p->returns_abnormally = current_function_returns_abnormally;
7038 p->warn_about_return_type = warn_about_return_type;
7039 p->extern_inline = current_extern_inline;
7040 p->binding_level = current_binding_level;
7041 }
7042
7043 /* Restore the variables used during compilation of a C function. */
7044
7045 void
7046 c_pop_function_context (f)
7047 struct function *f;
7048 {
7049 struct language_function *p = f->language;
7050 tree link;
7051
7052 /* Bring back all the labels that were shadowed. */
7053 for (link = shadowed_labels; link; link = TREE_CHAIN (link))
7054 if (DECL_NAME (TREE_VALUE (link)) != 0)
7055 IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link)))
7056 = TREE_VALUE (link);
7057
7058 if (DECL_SAVED_INSNS (current_function_decl) == 0
7059 && DECL_SAVED_TREE (current_function_decl) == NULL_TREE)
7060 {
7061 /* Stop pointing to the local nodes about to be freed. */
7062 /* But DECL_INITIAL must remain nonzero so we know this
7063 was an actual function definition. */
7064 DECL_INITIAL (current_function_decl) = error_mark_node;
7065 DECL_ARGUMENTS (current_function_decl) = 0;
7066 }
7067
7068 c_stmt_tree = p->base.x_stmt_tree;
7069 c_scope_stmt_stack = p->base.x_scope_stmt_stack;
7070 named_labels = p->named_labels;
7071 shadowed_labels = p->shadowed_labels;
7072 current_function_returns_value = p->returns_value;
7073 current_function_returns_null = p->returns_null;
7074 current_function_returns_abnormally = p->returns_abnormally;
7075 warn_about_return_type = p->warn_about_return_type;
7076 current_extern_inline = p->extern_inline;
7077 current_binding_level = p->binding_level;
7078
7079 f->language = NULL;
7080 }
7081
7082 /* Copy the DECL_LANG_SPECIFIC data associated with DECL. */
7083
7084 void
7085 c_dup_lang_specific_decl (decl)
7086 tree decl;
7087 {
7088 struct lang_decl *ld;
7089
7090 if (!DECL_LANG_SPECIFIC (decl))
7091 return;
7092
7093 ld = (struct lang_decl *) ggc_alloc (sizeof (struct lang_decl));
7094 memcpy ((char *) ld, (char *) DECL_LANG_SPECIFIC (decl),
7095 sizeof (struct lang_decl));
7096 DECL_LANG_SPECIFIC (decl) = ld;
7097 }
7098
7099 /* The functions below are required for functionality of doing
7100 function at once processing in the C front end. Currently these
7101 functions are not called from anywhere in the C front end, but as
7102 these changes continue, that will change. */
7103
7104 /* Returns non-zero if the current statement is a full expression,
7105 i.e. temporaries created during that statement should be destroyed
7106 at the end of the statement. */
7107
7108 int
7109 stmts_are_full_exprs_p ()
7110 {
7111 return 0;
7112 }
7113
7114 /* Returns the stmt_tree (if any) to which statements are currently
7115 being added. If there is no active statement-tree, NULL is
7116 returned. */
7117
7118 stmt_tree
7119 current_stmt_tree ()
7120 {
7121 return &c_stmt_tree;
7122 }
7123
7124 /* Returns the stack of SCOPE_STMTs for the current function. */
7125
7126 tree *
7127 current_scope_stmt_stack ()
7128 {
7129 return &c_scope_stmt_stack;
7130 }
7131
7132 /* Nonzero if TYPE is an anonymous union or struct type. Always 0 in
7133 C. */
7134
7135 int
7136 anon_aggr_type_p (node)
7137 tree node ATTRIBUTE_UNUSED;
7138 {
7139 return 0;
7140 }
7141
7142 /* Dummy function in place of callback used by C++. */
7143
7144 void
7145 extract_interface_info ()
7146 {
7147 }
7148
7149 /* Return a new COMPOUND_STMT, after adding it to the current
7150 statement tree. */
7151
7152 tree
7153 c_begin_compound_stmt ()
7154 {
7155 tree stmt;
7156
7157 /* Create the COMPOUND_STMT. */
7158 stmt = add_stmt (build_stmt (COMPOUND_STMT, NULL_TREE));
7159
7160 return stmt;
7161 }
7162
7163 /* Expand T (a DECL_STMT) if it declares an entity not handled by the
7164 common code. */
7165
7166 void
7167 c_expand_decl_stmt (t)
7168 tree t;
7169 {
7170 tree decl = DECL_STMT_DECL (t);
7171
7172 /* Expand nested functions. */
7173 if (TREE_CODE (decl) == FUNCTION_DECL
7174 && DECL_CONTEXT (decl) == current_function_decl
7175 && DECL_SAVED_TREE (decl))
7176 c_expand_body (decl, /*nested_p=*/1, /*can_defer_p=*/0);
7177 }
7178
7179 /* Return the IDENTIFIER_GLOBAL_VALUE of T, for use in common code, since
7180 the definition of IDENTIFIER_GLOBAL_VALUE is different for C and C++. */
7181
7182 tree
7183 identifier_global_value (t)
7184 tree t;
7185 {
7186 return IDENTIFIER_GLOBAL_VALUE (t);
7187 }
7188
7189 /* Record a builtin type for C. If NAME is non-NULL, it is the name used;
7190 otherwise the name is found in ridpointers from RID_INDEX. */
7191
7192 void
7193 record_builtin_type (rid_index, name, type)
7194 enum rid rid_index;
7195 const char *name;
7196 tree type;
7197 {
7198 tree id;
7199 if (name == 0)
7200 id = ridpointers[(int) rid_index];
7201 else
7202 id = get_identifier (name);
7203 pushdecl (build_decl (TYPE_DECL, id, type));
7204 }
7205
7206 /* Build the void_list_node (void_type_node having been created). */
7207 tree
7208 build_void_list_node ()
7209 {
7210 tree t = build_tree_list (NULL_TREE, void_type_node);
7211 return t;
7212 }
7213
7214 /* Return something to represent absolute declarators containing a *.
7215 TARGET is the absolute declarator that the * contains.
7216 TYPE_QUALS_ATTRS is a list of modifiers such as const or volatile
7217 to apply to the pointer type, represented as identifiers, possible mixed
7218 with attributes.
7219
7220 We return an INDIRECT_REF whose "contents" are TARGET (inside a TREE_LIST,
7221 if attributes are present) and whose type is the modifier list. */
7222
7223 tree
7224 make_pointer_declarator (type_quals_attrs, target)
7225 tree type_quals_attrs, target;
7226 {
7227 tree quals, attrs;
7228 tree itarget = target;
7229 split_specs_attrs (type_quals_attrs, &quals, &attrs);
7230 if (attrs != NULL_TREE)
7231 itarget = tree_cons (attrs, target, NULL_TREE);
7232 return build1 (INDIRECT_REF, quals, itarget);
7233 }
7234
7235 #include "gt-c-decl.h"