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