2001-07-10 Jan van Male <jan.vanmale@fenk.wau.nl>
[official-gcc.git] / gcc / c-decl.c
blobdc100db5ad4ae6bbf9a2c6158be8508bee9930d1
1 /* Process declarations and variables for C compiler.
2 Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
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. */
26 /* ??? not all decl nodes are given the most useful possible
27 line numbers. For example, the CONST_DECLs for enum values. */
29 #include "config.h"
30 #include "system.h"
31 #include "intl.h"
32 #include "tree.h"
33 #include "rtl.h"
34 #include "flags.h"
35 #include "function.h"
36 #include "output.h"
37 #include "expr.h"
38 #include "c-tree.h"
39 #include "c-lex.h"
40 #include "toplev.h"
41 #include "ggc.h"
42 #include "tm_p.h"
43 #include "cpplib.h"
44 #include "target.h"
46 /* In grokdeclarator, distinguish syntactic contexts of declarators. */
47 enum decl_context
48 { NORMAL, /* Ordinary declaration */
49 FUNCDEF, /* Function definition */
50 PARM, /* Declaration of parm before function body */
51 FIELD, /* Declaration inside struct or union */
52 BITFIELD, /* Likewise but with specified width */
53 TYPENAME}; /* Typename (inside cast or sizeof) */
56 /* Nonzero if we have seen an invalid cross reference
57 to a struct, union, or enum, but not yet printed the message. */
59 tree pending_invalid_xref;
60 /* File and line to appear in the eventual error message. */
61 const char *pending_invalid_xref_file;
62 int pending_invalid_xref_line;
64 /* While defining an enum type, this is 1 plus the last enumerator
65 constant value. Note that will do not have to save this or `enum_overflow'
66 around nested function definition since such a definition could only
67 occur in an enum value expression and we don't use these variables in
68 that case. */
70 static tree enum_next_value;
72 /* Nonzero means that there was overflow computing enum_next_value. */
74 static int enum_overflow;
76 /* Parsing a function declarator leaves a list of parameter names
77 or a chain or parameter decls here. */
79 static tree last_function_parms;
81 /* Parsing a function declarator leaves here a chain of structure
82 and enum types declared in the parmlist. */
84 static tree last_function_parm_tags;
86 /* After parsing the declarator that starts a function definition,
87 `start_function' puts here the list of parameter names or chain of decls.
88 `store_parm_decls' finds it here. */
90 static tree current_function_parms;
92 /* Similar, for last_function_parm_tags. */
93 static tree current_function_parm_tags;
95 /* Similar, for the file and line that the prototype came from if this is
96 an old-style definition. */
97 static const char *current_function_prototype_file;
98 static int current_function_prototype_line;
100 /* The current statement tree. */
102 static struct stmt_tree_s c_stmt_tree;
104 /* The current scope statement stack. */
106 static tree c_scope_stmt_stack;
108 /* A list (chain of TREE_LIST nodes) of all LABEL_DECLs in the function
109 that have names. Here so we can clear out their names' definitions
110 at the end of the function. */
112 static tree named_labels;
114 /* A list of LABEL_DECLs from outer contexts that are currently shadowed. */
116 static tree shadowed_labels;
118 /* Nonzero when store_parm_decls is called indicates a varargs function.
119 Value not meaningful after store_parm_decls. */
121 static int c_function_varargs;
123 /* Set to 0 at beginning of a function definition, set to 1 if
124 a return statement that specifies a return value is seen. */
126 int current_function_returns_value;
128 /* Set to 0 at beginning of a function definition, set to 1 if
129 a return statement with no argument is seen. */
131 int current_function_returns_null;
133 /* Set to nonzero by `grokdeclarator' for a function
134 whose return type is defaulted, if warnings for this are desired. */
136 static int warn_about_return_type;
138 /* Nonzero when starting a function declared `extern inline'. */
140 static int current_extern_inline;
142 /* For each binding contour we allocate a binding_level structure
143 * which records the names defined in that contour.
144 * Contours include:
145 * 0) the global one
146 * 1) one for each function definition,
147 * where internal declarations of the parameters appear.
148 * 2) one for each compound statement,
149 * to record its declarations.
151 * The current meaning of a name can be found by searching the levels from
152 * the current one out to the global one.
155 /* Note that the information in the `names' component of the global contour
156 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */
158 struct binding_level
160 /* A chain of _DECL nodes for all variables, constants, functions,
161 and typedef types. These are in the reverse of the order supplied.
163 tree names;
165 /* A list of structure, union and enum definitions,
166 * for looking up tag names.
167 * It is a chain of TREE_LIST nodes, each of whose TREE_PURPOSE is a name,
168 * or NULL_TREE; and whose TREE_VALUE is a RECORD_TYPE, UNION_TYPE,
169 * or ENUMERAL_TYPE node.
171 tree tags;
173 /* For each level, a list of shadowed outer-level local definitions
174 to be restored when this level is popped.
175 Each link is a TREE_LIST whose TREE_PURPOSE is an identifier and
176 whose TREE_VALUE is its old definition (a kind of ..._DECL node). */
177 tree shadowed;
179 /* For each level (except not the global one),
180 a chain of BLOCK nodes for all the levels
181 that were entered and exited one level down. */
182 tree blocks;
184 /* The BLOCK node for this level, if one has been preallocated.
185 If 0, the BLOCK is allocated (if needed) when the level is popped. */
186 tree this_block;
188 /* The binding level which this one is contained in (inherits from). */
189 struct binding_level *level_chain;
191 /* Nonzero for the level that holds the parameters of a function. */
192 char parm_flag;
194 /* Nonzero if this level "doesn't exist" for tags. */
195 char tag_transparent;
197 /* Nonzero if sublevels of this level "don't exist" for tags.
198 This is set in the parm level of a function definition
199 while reading the function body, so that the outermost block
200 of the function body will be tag-transparent. */
201 char subblocks_tag_transparent;
203 /* Nonzero means make a BLOCK for this level regardless of all else. */
204 char keep;
206 /* Nonzero means make a BLOCK if this level has any subblocks. */
207 char keep_if_subblocks;
209 /* Number of decls in `names' that have incomplete
210 structure or union types. */
211 int n_incomplete;
213 /* A list of decls giving the (reversed) specified order of parms,
214 not including any forward-decls in the parmlist.
215 This is so we can put the parms in proper order for assign_parms. */
216 tree parm_order;
219 #define NULL_BINDING_LEVEL (struct binding_level *) NULL
221 /* The binding level currently in effect. */
223 static struct binding_level *current_binding_level;
225 /* A chain of binding_level structures awaiting reuse. */
227 static struct binding_level *free_binding_level;
229 /* The outermost binding level, for names of file scope.
230 This is created when the compiler is started and exists
231 through the entire run. */
233 static struct binding_level *global_binding_level;
235 /* Binding level structures are initialized by copying this one. */
237 static struct binding_level clear_binding_level
238 = {NULL, NULL, NULL, NULL, NULL, NULL_BINDING_LEVEL, 0, 0, 0, 0, 0, 0,
239 NULL};
241 /* Nonzero means unconditionally make a BLOCK for the next level pushed. */
243 static int keep_next_level_flag;
245 /* Nonzero means make a BLOCK for the next level pushed
246 if it has subblocks. */
248 static int keep_next_if_subblocks;
250 /* The chain of outer levels of label scopes.
251 This uses the same data structure used for binding levels,
252 but it works differently: each link in the chain records
253 saved values of named_labels and shadowed_labels for
254 a label binding level outside the current one. */
256 static struct binding_level *label_level_chain;
258 /* Functions called automatically at the beginning and end of execution. */
260 tree static_ctors, static_dtors;
262 /* Forward declarations. */
264 static struct binding_level * make_binding_level PARAMS ((void));
265 static void mark_binding_level PARAMS ((void *));
266 static void clear_limbo_values PARAMS ((tree));
267 static int duplicate_decls PARAMS ((tree, tree, int));
268 static int redeclaration_error_message PARAMS ((tree, tree));
269 static void storedecls PARAMS ((tree));
270 static void storetags PARAMS ((tree));
271 static tree lookup_tag PARAMS ((enum tree_code, tree,
272 struct binding_level *, int));
273 static tree lookup_tag_reverse PARAMS ((tree));
274 static tree grokdeclarator PARAMS ((tree, tree, enum decl_context,
275 int));
276 static tree grokparms PARAMS ((tree, int));
277 static void layout_array_type PARAMS ((tree));
278 static tree c_make_fname_decl PARAMS ((tree, int));
279 static void c_expand_body PARAMS ((tree, int));
281 /* C-specific option variables. */
283 /* Nonzero means allow type mismatches in conditional expressions;
284 just make their values `void'. */
286 int flag_cond_mismatch;
288 /* Nonzero means don't recognize the keyword `asm'. */
290 int flag_no_asm;
292 /* Nonzero means do some things the same way PCC does. */
294 int flag_traditional;
296 /* Nonzero means enable C89 Amendment 1 features. */
298 int flag_isoc94 = 0;
300 /* Nonzero means use the ISO C99 dialect of C. */
302 int flag_isoc99 = 0;
304 /* Nonzero means that we have builtin functions, and main is an int */
306 int flag_hosted = 1;
308 /* Nonzero means add default format_arg attributes for functions not
309 in ISO C. */
311 int flag_noniso_default_format_attributes = 1;
313 /* Nonzero means to allow single precision math even if we're generally
314 being traditional. */
315 int flag_allow_single_precision = 0;
317 /* Nonzero means to treat bitfields as signed unless they say `unsigned'. */
319 int flag_signed_bitfields = 1;
320 int explicit_flag_signed_bitfields = 0;
322 /* Nonzero means warn about use of implicit int. */
324 int warn_implicit_int;
326 /* Nonzero means warn about usage of long long when `-pedantic'. */
328 int warn_long_long = 1;
330 /* Nonzero means message about use of implicit function declarations;
331 1 means warning; 2 means error. */
333 int mesg_implicit_function_declaration = -1;
335 /* Nonzero means give string constants the type `const char *'
336 to get extra warnings from them. These warnings will be too numerous
337 to be useful, except in thoroughly ANSIfied programs. */
339 int flag_const_strings;
341 /* Nonzero means warn about pointer casts that can drop a type qualifier
342 from the pointer target type. */
344 int warn_cast_qual;
346 /* Nonzero means warn when casting a function call to a type that does
347 not match the return type (e.g. (float)sqrt() or (anything*)malloc()
348 when there is no previous declaration of sqrt or malloc. */
350 int warn_bad_function_cast;
352 /* Warn about functions which might be candidates for format attributes. */
354 int warn_missing_format_attribute;
356 /* Warn about traditional constructs whose meanings changed in ANSI C. */
358 int warn_traditional;
360 /* Nonzero means warn about sizeof(function) or addition/subtraction
361 of function pointers. */
363 int warn_pointer_arith;
365 /* Nonzero means warn for non-prototype function decls
366 or non-prototyped defs without previous prototype. */
368 int warn_strict_prototypes;
370 /* Nonzero means warn for any global function def
371 without separate previous prototype decl. */
373 int warn_missing_prototypes;
375 /* Nonzero means warn for any global function def
376 without separate previous decl. */
378 int warn_missing_declarations;
380 /* Nonzero means warn about multiple (redundant) decls for the same single
381 variable or function. */
383 int warn_redundant_decls = 0;
385 /* Nonzero means warn about extern declarations of objects not at
386 file-scope level and about *all* declarations of functions (whether
387 extern or static) not at file-scope level. Note that we exclude
388 implicit function declarations. To get warnings about those, use
389 -Wimplicit. */
391 int warn_nested_externs = 0;
393 /* Warn about a subscript that has type char. */
395 int warn_char_subscripts = 0;
397 /* Warn if a type conversion is done that might have confusing results. */
399 int warn_conversion;
401 /* Warn if adding () is suggested. */
403 int warn_parentheses;
405 /* Warn if initializer is not completely bracketed. */
407 int warn_missing_braces;
409 /* Warn if main is suspicious. */
411 int warn_main;
413 /* Warn about #pragma directives that are not recognised. */
415 int warn_unknown_pragmas = 0; /* Tri state variable. */
417 /* Warn about comparison of signed and unsigned values.
418 If -1, neither -Wsign-compare nor -Wno-sign-compare has been specified. */
420 int warn_sign_compare = -1;
422 /* Warn about testing equality of floating point numbers. */
424 int warn_float_equal = 0;
426 /* Nonzero means warn about use of multicharacter literals. */
428 int warn_multichar = 1;
430 /* The variant of the C language being processed. */
432 c_language_kind c_language = clk_c;
434 /* Nonzero means `$' can be in an identifier. */
436 #ifndef DOLLARS_IN_IDENTIFIERS
437 #define DOLLARS_IN_IDENTIFIERS 1
438 #endif
439 int dollars_in_ident = DOLLARS_IN_IDENTIFIERS;
441 /* Decode the string P as a language-specific option for C.
442 Return the number of strings consumed. Should not complain
443 if it does not recognise the option. */
446 c_decode_option (argc, argv)
447 int argc ATTRIBUTE_UNUSED;
448 char **argv;
450 int strings_processed;
451 char *p = argv[0];
453 strings_processed = cpp_handle_option (parse_in, argc, argv);
455 if (!strcmp (p, "-ftraditional") || !strcmp (p, "-traditional"))
457 flag_traditional = 1;
458 flag_writable_strings = 1;
460 else if (!strcmp (p, "-fallow-single-precision"))
461 flag_allow_single_precision = 1;
462 else if (!strcmp (p, "-fhosted") || !strcmp (p, "-fno-freestanding"))
464 flag_hosted = 1;
465 flag_no_builtin = 0;
467 else if (!strcmp (p, "-ffreestanding") || !strcmp (p, "-fno-hosted"))
469 flag_hosted = 0;
470 flag_no_builtin = 1;
471 /* warn_main will be 2 if set by -Wall, 1 if set by -Wmain */
472 if (warn_main == 2)
473 warn_main = 0;
475 else if (!strcmp (p, "-fnotraditional") || !strcmp (p, "-fno-traditional"))
477 flag_traditional = 0;
478 flag_writable_strings = 0;
480 else if (!strncmp (p, "-std=", 5))
482 /* Select the appropriate language standard. We currently
483 recognize:
484 -std=iso9899:1990 same as -ansi
485 -std=iso9899:199409 ISO C as modified in amend. 1
486 -std=iso9899:1999 ISO C 99
487 -std=c89 same as -std=iso9899:1990
488 -std=c99 same as -std=iso9899:1999
489 -std=gnu89 default, iso9899:1990 + gnu extensions
490 -std=gnu99 iso9899:1999 + gnu extensions
492 const char *argstart = &p[5];
494 if (!strcmp (argstart, "iso9899:1990")
495 || !strcmp (argstart, "c89"))
497 iso_1990:
498 flag_isoc94 = 0;
499 iso_1994:
500 flag_traditional = 0;
501 flag_writable_strings = 0;
502 flag_no_asm = 1;
503 flag_no_nonansi_builtin = 1;
504 flag_noniso_default_format_attributes = 0;
505 flag_isoc99 = 0;
507 else if (!strcmp (argstart, "iso9899:199409"))
509 flag_isoc94 = 1;
510 goto iso_1994;
512 else if (!strcmp (argstart, "iso9899:199x")
513 || !strcmp (argstart, "iso9899:1999")
514 || !strcmp (argstart, "c9x")
515 || !strcmp (argstart, "c99"))
517 flag_traditional = 0;
518 flag_writable_strings = 0;
519 flag_no_asm = 1;
520 flag_no_nonansi_builtin = 1;
521 flag_noniso_default_format_attributes = 0;
522 flag_isoc99 = 1;
523 flag_isoc94 = 1;
525 else if (!strcmp (argstart, "gnu89"))
527 flag_traditional = 0;
528 flag_writable_strings = 0;
529 flag_no_asm = 0;
530 flag_no_nonansi_builtin = 0;
531 flag_noniso_default_format_attributes = 1;
532 flag_isoc99 = 0;
533 flag_isoc94 = 0;
535 else if (!strcmp (argstart, "gnu9x") || !strcmp (argstart, "gnu99"))
537 flag_traditional = 0;
538 flag_writable_strings = 0;
539 flag_no_asm = 0;
540 flag_no_nonansi_builtin = 0;
541 flag_noniso_default_format_attributes = 1;
542 flag_isoc99 = 1;
543 flag_isoc94 = 1;
545 else
546 error ("unknown C standard `%s'", argstart);
548 else if (!strcmp (p, "-fdollars-in-identifiers"))
549 dollars_in_ident = 1;
550 else if (!strcmp (p, "-fno-dollars-in-identifiers"))
551 dollars_in_ident = 0;
552 else if (!strcmp (p, "-fsigned-char"))
553 flag_signed_char = 1;
554 else if (!strcmp (p, "-funsigned-char"))
555 flag_signed_char = 0;
556 else if (!strcmp (p, "-fno-signed-char"))
557 flag_signed_char = 0;
558 else if (!strcmp (p, "-fno-unsigned-char"))
559 flag_signed_char = 1;
560 else if (!strcmp (p, "-fsigned-bitfields")
561 || !strcmp (p, "-fno-unsigned-bitfields"))
563 flag_signed_bitfields = 1;
564 explicit_flag_signed_bitfields = 1;
566 else if (!strcmp (p, "-funsigned-bitfields")
567 || !strcmp (p, "-fno-signed-bitfields"))
569 flag_signed_bitfields = 0;
570 explicit_flag_signed_bitfields = 1;
572 else if (!strcmp (p, "-fshort-enums"))
573 flag_short_enums = 1;
574 else if (!strcmp (p, "-fno-short-enums"))
575 flag_short_enums = 0;
576 else if (!strcmp (p, "-fshort-wchar"))
577 flag_short_wchar = 1;
578 else if (!strcmp (p, "-fno-short-wchar"))
579 flag_short_wchar = 0;
580 else if (!strcmp (p, "-fcond-mismatch"))
581 flag_cond_mismatch = 1;
582 else if (!strcmp (p, "-fno-cond-mismatch"))
583 flag_cond_mismatch = 0;
584 else if (!strcmp (p, "-fshort-double"))
585 flag_short_double = 1;
586 else if (!strcmp (p, "-fno-short-double"))
587 flag_short_double = 0;
588 else if (!strcmp (p, "-fasm"))
589 flag_no_asm = 0;
590 else if (!strcmp (p, "-fno-asm"))
591 flag_no_asm = 1;
592 else if (!strcmp (p, "-fbuiltin"))
593 flag_no_builtin = 0;
594 else if (!strcmp (p, "-fno-builtin"))
595 flag_no_builtin = 1;
596 else if (dump_switch_p (p))
598 else if (!strcmp (p, "-ansi"))
599 goto iso_1990;
600 else if (!strcmp (p, "-Werror-implicit-function-declaration"))
601 mesg_implicit_function_declaration = 2;
602 else if (!strcmp (p, "-Wimplicit-function-declaration"))
603 mesg_implicit_function_declaration = 1;
604 else if (!strcmp (p, "-Wno-implicit-function-declaration"))
605 mesg_implicit_function_declaration = 0;
606 else if (!strcmp (p, "-Wimplicit-int"))
607 warn_implicit_int = 1;
608 else if (!strcmp (p, "-Wno-implicit-int"))
609 warn_implicit_int = 0;
610 else if (!strcmp (p, "-Wimplicit"))
612 warn_implicit_int = 1;
613 if (mesg_implicit_function_declaration != 2)
614 mesg_implicit_function_declaration = 1;
616 else if (!strcmp (p, "-Wno-implicit"))
617 warn_implicit_int = 0, mesg_implicit_function_declaration = 0;
618 else if (!strcmp (p, "-Wlong-long"))
619 warn_long_long = 1;
620 else if (!strcmp (p, "-Wno-long-long"))
621 warn_long_long = 0;
622 else if (!strcmp (p, "-Wwrite-strings"))
623 flag_const_strings = 1;
624 else if (!strcmp (p, "-Wno-write-strings"))
625 flag_const_strings = 0;
626 else if (!strcmp (p, "-Wcast-qual"))
627 warn_cast_qual = 1;
628 else if (!strcmp (p, "-Wno-cast-qual"))
629 warn_cast_qual = 0;
630 else if (!strcmp (p, "-Wbad-function-cast"))
631 warn_bad_function_cast = 1;
632 else if (!strcmp (p, "-Wno-bad-function-cast"))
633 warn_bad_function_cast = 0;
634 else if (!strcmp (p, "-Wno-missing-noreturn"))
635 warn_missing_noreturn = 0;
636 else if (!strcmp (p, "-Wmissing-format-attribute"))
637 warn_missing_format_attribute = 1;
638 else if (!strcmp (p, "-Wno-missing-format-attribute"))
639 warn_missing_format_attribute = 0;
640 else if (!strcmp (p, "-Wpointer-arith"))
641 warn_pointer_arith = 1;
642 else if (!strcmp (p, "-Wno-pointer-arith"))
643 warn_pointer_arith = 0;
644 else if (!strcmp (p, "-Wstrict-prototypes"))
645 warn_strict_prototypes = 1;
646 else if (!strcmp (p, "-Wno-strict-prototypes"))
647 warn_strict_prototypes = 0;
648 else if (!strcmp (p, "-Wmissing-prototypes"))
649 warn_missing_prototypes = 1;
650 else if (!strcmp (p, "-Wno-missing-prototypes"))
651 warn_missing_prototypes = 0;
652 else if (!strcmp (p, "-Wmissing-declarations"))
653 warn_missing_declarations = 1;
654 else if (!strcmp (p, "-Wno-missing-declarations"))
655 warn_missing_declarations = 0;
656 else if (!strcmp (p, "-Wredundant-decls"))
657 warn_redundant_decls = 1;
658 else if (!strcmp (p, "-Wno-redundant-decls"))
659 warn_redundant_decls = 0;
660 else if (!strcmp (p, "-Wnested-externs"))
661 warn_nested_externs = 1;
662 else if (!strcmp (p, "-Wno-nested-externs"))
663 warn_nested_externs = 0;
664 else if (!strcmp (p, "-Wtraditional"))
665 warn_traditional = 1;
666 else if (!strcmp (p, "-Wno-traditional"))
667 warn_traditional = 0;
668 else if (!strncmp (p, "-Wformat=", 9))
669 set_Wformat (atoi (p + 9));
670 else if (!strcmp (p, "-Wformat"))
671 set_Wformat (1);
672 else if (!strcmp (p, "-Wno-format"))
673 set_Wformat (0);
674 else if (!strcmp (p, "-Wformat-y2k"))
675 warn_format_y2k = 1;
676 else if (!strcmp (p, "-Wno-format-y2k"))
677 warn_format_y2k = 0;
678 else if (!strcmp (p, "-Wformat-extra-args"))
679 warn_format_extra_args = 1;
680 else if (!strcmp (p, "-Wno-format-extra-args"))
681 warn_format_extra_args = 0;
682 else if (!strcmp (p, "-Wformat-nonliteral"))
683 warn_format_nonliteral = 1;
684 else if (!strcmp (p, "-Wno-format-nonliteral"))
685 warn_format_nonliteral = 0;
686 else if (!strcmp (p, "-Wformat-security"))
687 warn_format_security = 1;
688 else if (!strcmp (p, "-Wno-format-security"))
689 warn_format_security = 0;
690 else if (!strcmp (p, "-Wchar-subscripts"))
691 warn_char_subscripts = 1;
692 else if (!strcmp (p, "-Wno-char-subscripts"))
693 warn_char_subscripts = 0;
694 else if (!strcmp (p, "-Wconversion"))
695 warn_conversion = 1;
696 else if (!strcmp (p, "-Wno-conversion"))
697 warn_conversion = 0;
698 else if (!strcmp (p, "-Wparentheses"))
699 warn_parentheses = 1;
700 else if (!strcmp (p, "-Wno-parentheses"))
701 warn_parentheses = 0;
702 else if (!strcmp (p, "-Wreturn-type"))
703 warn_return_type = 1;
704 else if (!strcmp (p, "-Wno-return-type"))
705 warn_return_type = 0;
706 else if (!strcmp (p, "-Wsequence-point"))
707 warn_sequence_point = 1;
708 else if (!strcmp (p, "-Wno-sequence-point"))
709 warn_sequence_point = 0;
710 else if (!strcmp (p, "-Wcomment"))
711 ; /* cpp handles this one. */
712 else if (!strcmp (p, "-Wno-comment"))
713 ; /* cpp handles this one. */
714 else if (!strcmp (p, "-Wcomments"))
715 ; /* cpp handles this one. */
716 else if (!strcmp (p, "-Wno-comments"))
717 ; /* cpp handles this one. */
718 else if (!strcmp (p, "-Wtrigraphs"))
719 ; /* cpp handles this one. */
720 else if (!strcmp (p, "-Wno-trigraphs"))
721 ; /* cpp handles this one. */
722 else if (!strcmp (p, "-Wundef"))
723 ; /* cpp handles this one. */
724 else if (!strcmp (p, "-Wno-undef"))
725 ; /* cpp handles this one. */
726 else if (!strcmp (p, "-Wimport"))
727 ; /* cpp handles this one. */
728 else if (!strcmp (p, "-Wno-import"))
729 ; /* cpp handles this one. */
730 else if (!strcmp (p, "-Wmissing-braces"))
731 warn_missing_braces = 1;
732 else if (!strcmp (p, "-Wno-missing-braces"))
733 warn_missing_braces = 0;
734 else if (!strcmp (p, "-Wmain"))
735 warn_main = 1;
736 else if (!strcmp (p, "-Wno-main"))
737 warn_main = -1;
738 else if (!strcmp (p, "-Wsign-compare"))
739 warn_sign_compare = 1;
740 else if (!strcmp (p, "-Wno-sign-compare"))
741 warn_sign_compare = 0;
742 else if (!strcmp (p, "-Wfloat-equal"))
743 warn_float_equal = 1;
744 else if (!strcmp (p, "-Wno-float-equal"))
745 warn_float_equal = 0;
746 else if (!strcmp (p, "-Wmultichar"))
747 warn_multichar = 1;
748 else if (!strcmp (p, "-Wno-multichar"))
749 warn_multichar = 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"))
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;
779 else
780 return strings_processed;
782 return 1;
785 /* Hooks for print_node. */
787 void
788 print_lang_decl (file, node, indent)
789 FILE *file ATTRIBUTE_UNUSED;
790 tree node ATTRIBUTE_UNUSED;
791 int indent ATTRIBUTE_UNUSED;
795 void
796 print_lang_type (file, node, indent)
797 FILE *file ATTRIBUTE_UNUSED;
798 tree node ATTRIBUTE_UNUSED;
799 int indent ATTRIBUTE_UNUSED;
803 void
804 print_lang_identifier (file, node, indent)
805 FILE *file;
806 tree node;
807 int indent;
809 print_node (file, "global", IDENTIFIER_GLOBAL_VALUE (node), indent + 4);
810 print_node (file, "local", IDENTIFIER_LOCAL_VALUE (node), indent + 4);
811 print_node (file, "label", IDENTIFIER_LABEL_VALUE (node), indent + 4);
812 print_node (file, "implicit", IDENTIFIER_IMPLICIT_DECL (node), indent + 4);
813 print_node (file, "error locus", IDENTIFIER_ERROR_LOCUS (node), indent + 4);
814 print_node (file, "limbo value", IDENTIFIER_LIMBO_VALUE (node), indent + 4);
815 if (C_IS_RESERVED_WORD (node))
817 tree rid = ridpointers[C_RID_CODE (node)];
818 indent_to (file, indent + 4);
819 fprintf (file, "rid ");
820 fprintf (file, HOST_PTR_PRINTF, (void *)rid);
821 fprintf (file, " \"%s\"", IDENTIFIER_POINTER (rid));
825 /* Hook called at end of compilation to assume 1 elt
826 for a top-level tentative array defn that wasn't complete before. */
828 void
829 finish_incomplete_decl (decl)
830 tree decl;
832 if (TREE_CODE (decl) == VAR_DECL)
834 tree type = TREE_TYPE (decl);
835 if (type != error_mark_node
836 && TREE_CODE (type) == ARRAY_TYPE
837 && ! DECL_EXTERNAL (decl)
838 && TYPE_DOMAIN (type) == 0)
840 warning_with_decl (decl, "array `%s' assumed to have one element");
842 complete_array_type (type, NULL_TREE, 1);
844 layout_decl (decl, 0);
849 /* Create a new `struct binding_level'. */
851 static struct binding_level *
852 make_binding_level ()
854 /* NOSTRICT */
855 return (struct binding_level *) xmalloc (sizeof (struct binding_level));
858 /* Nonzero if we are currently in the global binding level. */
861 global_bindings_p ()
863 return current_binding_level == global_binding_level;
866 void
867 keep_next_level ()
869 keep_next_level_flag = 1;
872 /* Nonzero if the current level needs to have a BLOCK made. */
875 kept_level_p ()
877 return ((current_binding_level->keep_if_subblocks
878 && current_binding_level->blocks != 0)
879 || current_binding_level->keep
880 || current_binding_level->names != 0
881 || (current_binding_level->tags != 0
882 && !current_binding_level->tag_transparent));
885 /* Identify this binding level as a level of parameters.
886 DEFINITION_FLAG is 1 for a definition, 0 for a declaration.
887 But it turns out there is no way to pass the right value for
888 DEFINITION_FLAG, so we ignore it. */
890 void
891 declare_parm_level (definition_flag)
892 int definition_flag ATTRIBUTE_UNUSED;
894 current_binding_level->parm_flag = 1;
897 /* Nonzero if currently making parm declarations. */
900 in_parm_level_p ()
902 return current_binding_level->parm_flag;
905 /* Enter a new binding level.
906 If TAG_TRANSPARENT is nonzero, do so only for the name space of variables,
907 not for that of tags. */
909 void
910 pushlevel (tag_transparent)
911 int tag_transparent;
913 register struct binding_level *newlevel = NULL_BINDING_LEVEL;
915 /* If this is the top level of a function,
916 just make sure that NAMED_LABELS is 0. */
918 if (current_binding_level == global_binding_level)
920 named_labels = 0;
923 /* Reuse or create a struct for this binding level. */
925 if (free_binding_level)
927 newlevel = free_binding_level;
928 free_binding_level = free_binding_level->level_chain;
930 else
932 newlevel = make_binding_level ();
935 /* Add this level to the front of the chain (stack) of levels that
936 are active. */
938 *newlevel = clear_binding_level;
939 newlevel->tag_transparent
940 = (tag_transparent
941 || (current_binding_level
942 ? current_binding_level->subblocks_tag_transparent
943 : 0));
944 newlevel->level_chain = current_binding_level;
945 current_binding_level = newlevel;
946 newlevel->keep = keep_next_level_flag;
947 keep_next_level_flag = 0;
948 newlevel->keep_if_subblocks = keep_next_if_subblocks;
949 keep_next_if_subblocks = 0;
952 /* Clear the limbo values of all identifiers defined in BLOCK or a subblock. */
954 static void
955 clear_limbo_values (block)
956 tree block;
958 tree tem;
960 for (tem = BLOCK_VARS (block); tem; tem = TREE_CHAIN (tem))
961 if (DECL_NAME (tem) != 0)
962 IDENTIFIER_LIMBO_VALUE (DECL_NAME (tem)) = 0;
964 for (tem = BLOCK_SUBBLOCKS (block); tem; tem = TREE_CHAIN (tem))
965 clear_limbo_values (tem);
968 /* Exit a binding level.
969 Pop the level off, and restore the state of the identifier-decl mappings
970 that were in effect when this level was entered.
972 If KEEP is nonzero, this level had explicit declarations, so
973 and create a "block" (a BLOCK node) for the level
974 to record its declarations and subblocks for symbol table output.
976 If FUNCTIONBODY is nonzero, this level is the body of a function,
977 so create a block as if KEEP were set and also clear out all
978 label names.
980 If REVERSE is nonzero, reverse the order of decls before putting
981 them into the BLOCK. */
983 tree
984 poplevel (keep, reverse, functionbody)
985 int keep;
986 int reverse;
987 int functionbody;
989 register tree link;
990 /* The chain of decls was accumulated in reverse order.
991 Put it into forward order, just for cleanliness. */
992 tree decls;
993 tree tags = current_binding_level->tags;
994 tree subblocks = current_binding_level->blocks;
995 tree block = 0;
996 tree decl;
997 int block_previously_created;
999 keep |= current_binding_level->keep;
1001 /* This warning is turned off because it causes warnings for
1002 declarations like `extern struct foo *x'. */
1003 #if 0
1004 /* Warn about incomplete structure types in this level. */
1005 for (link = tags; link; link = TREE_CHAIN (link))
1006 if (!COMPLETE_TYPE_P (TREE_VALUE (link)))
1008 tree type = TREE_VALUE (link);
1009 tree type_name = TYPE_NAME (type);
1010 char *id = IDENTIFIER_POINTER (TREE_CODE (type_name) == IDENTIFIER_NODE
1011 ? type_name
1012 : DECL_NAME (type_name));
1013 switch (TREE_CODE (type))
1015 case RECORD_TYPE:
1016 error ("`struct %s' incomplete in scope ending here", id);
1017 break;
1018 case UNION_TYPE:
1019 error ("`union %s' incomplete in scope ending here", id);
1020 break;
1021 case ENUMERAL_TYPE:
1022 error ("`enum %s' incomplete in scope ending here", id);
1023 break;
1026 #endif /* 0 */
1028 /* Get the decls in the order they were written.
1029 Usually current_binding_level->names is in reverse order.
1030 But parameter decls were previously put in forward order. */
1032 if (reverse)
1033 current_binding_level->names
1034 = decls = nreverse (current_binding_level->names);
1035 else
1036 decls = current_binding_level->names;
1038 /* Output any nested inline functions within this block
1039 if they weren't already output. */
1041 for (decl = decls; decl; decl = TREE_CHAIN (decl))
1042 if (TREE_CODE (decl) == FUNCTION_DECL
1043 && ! TREE_ASM_WRITTEN (decl)
1044 && DECL_INITIAL (decl) != 0
1045 && TREE_ADDRESSABLE (decl))
1047 /* If this decl was copied from a file-scope decl
1048 on account of a block-scope extern decl,
1049 propagate TREE_ADDRESSABLE to the file-scope decl.
1051 DECL_ABSTRACT_ORIGIN can be set to itself if warn_return_type is
1052 true, since then the decl goes through save_for_inline_copying. */
1053 if (DECL_ABSTRACT_ORIGIN (decl) != 0
1054 && DECL_ABSTRACT_ORIGIN (decl) != decl)
1055 TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (decl)) = 1;
1058 /* We used to warn about unused variables in expand_end_bindings,
1059 i.e. while generating RTL. But in function-at-a-time mode we may
1060 choose to never expand a function at all (e.g. auto inlining), so
1061 we do this explicitly now. */
1062 warn_about_unused_variables (getdecls ());
1064 /* If there were any declarations or structure tags in that level,
1065 or if this level is a function body,
1066 create a BLOCK to record them for the life of this function. */
1068 block = 0;
1069 block_previously_created = (current_binding_level->this_block != 0);
1070 if (block_previously_created)
1071 block = current_binding_level->this_block;
1072 else if (keep || functionbody
1073 || (current_binding_level->keep_if_subblocks && subblocks != 0))
1074 block = make_node (BLOCK);
1075 if (block != 0)
1077 BLOCK_VARS (block) = decls;
1078 BLOCK_SUBBLOCKS (block) = subblocks;
1081 /* In each subblock, record that this is its superior. */
1083 for (link = subblocks; link; link = TREE_CHAIN (link))
1084 BLOCK_SUPERCONTEXT (link) = block;
1086 /* Clear out the meanings of the local variables of this level. */
1088 for (link = decls; link; link = TREE_CHAIN (link))
1090 if (DECL_NAME (link) != 0)
1092 /* If the ident. was used or addressed via a local extern decl,
1093 don't forget that fact. */
1094 if (DECL_EXTERNAL (link))
1096 if (TREE_USED (link))
1097 TREE_USED (DECL_NAME (link)) = 1;
1098 if (TREE_ADDRESSABLE (link))
1099 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (link)) = 1;
1101 IDENTIFIER_LOCAL_VALUE (DECL_NAME (link)) = 0;
1105 /* Restore all name-meanings of the outer levels
1106 that were shadowed by this level. */
1108 for (link = current_binding_level->shadowed; link; link = TREE_CHAIN (link))
1109 IDENTIFIER_LOCAL_VALUE (TREE_PURPOSE (link)) = TREE_VALUE (link);
1111 /* If the level being exited is the top level of a function,
1112 check over all the labels, and clear out the current
1113 (function local) meanings of their names. */
1115 if (functionbody)
1117 clear_limbo_values (block);
1119 /* If this is the top level block of a function,
1120 the vars are the function's parameters.
1121 Don't leave them in the BLOCK because they are
1122 found in the FUNCTION_DECL instead. */
1124 BLOCK_VARS (block) = 0;
1126 /* Clear out the definitions of all label names,
1127 since their scopes end here,
1128 and add them to BLOCK_VARS. */
1130 for (link = named_labels; link; link = TREE_CHAIN (link))
1132 register tree label = TREE_VALUE (link);
1134 if (DECL_INITIAL (label) == 0)
1136 error_with_decl (label, "label `%s' used but not defined");
1137 /* Avoid crashing later. */
1138 define_label (input_filename, lineno,
1139 DECL_NAME (label));
1141 else if (warn_unused_label && !TREE_USED (label))
1142 warning_with_decl (label, "label `%s' defined but not used");
1143 IDENTIFIER_LABEL_VALUE (DECL_NAME (label)) = 0;
1145 /* Put the labels into the "variables" of the
1146 top-level block, so debugger can see them. */
1147 TREE_CHAIN (label) = BLOCK_VARS (block);
1148 BLOCK_VARS (block) = label;
1152 /* Pop the current level, and free the structure for reuse. */
1155 register struct binding_level *level = current_binding_level;
1156 current_binding_level = current_binding_level->level_chain;
1158 level->level_chain = free_binding_level;
1159 free_binding_level = level;
1162 /* Dispose of the block that we just made inside some higher level. */
1163 if (functionbody)
1164 DECL_INITIAL (current_function_decl) = block;
1165 else if (block)
1167 if (!block_previously_created)
1168 current_binding_level->blocks
1169 = chainon (current_binding_level->blocks, block);
1171 /* If we did not make a block for the level just exited,
1172 any blocks made for inner levels
1173 (since they cannot be recorded as subblocks in that level)
1174 must be carried forward so they will later become subblocks
1175 of something else. */
1176 else if (subblocks)
1177 current_binding_level->blocks
1178 = chainon (current_binding_level->blocks, subblocks);
1180 /* Set the TYPE_CONTEXTs for all of the tagged types belonging to this
1181 binding contour so that they point to the appropriate construct, i.e.
1182 either to the current FUNCTION_DECL node, or else to the BLOCK node
1183 we just constructed.
1185 Note that for tagged types whose scope is just the formal parameter
1186 list for some function type specification, we can't properly set
1187 their TYPE_CONTEXTs here, because we don't have a pointer to the
1188 appropriate FUNCTION_TYPE node readily available to us. For those
1189 cases, the TYPE_CONTEXTs of the relevant tagged type nodes get set
1190 in `grokdeclarator' as soon as we have created the FUNCTION_TYPE
1191 node which will represent the "scope" for these "parameter list local"
1192 tagged types. */
1194 if (functionbody)
1195 for (link = tags; link; link = TREE_CHAIN (link))
1196 TYPE_CONTEXT (TREE_VALUE (link)) = current_function_decl;
1197 else if (block)
1198 for (link = tags; link; link = TREE_CHAIN (link))
1199 TYPE_CONTEXT (TREE_VALUE (link)) = block;
1201 if (block)
1202 TREE_USED (block) = 1;
1204 return block;
1207 /* Delete the node BLOCK from the current binding level.
1208 This is used for the block inside a stmt expr ({...})
1209 so that the block can be reinserted where appropriate. */
1211 void
1212 delete_block (block)
1213 tree block;
1215 tree t;
1216 if (current_binding_level->blocks == block)
1217 current_binding_level->blocks = TREE_CHAIN (block);
1218 for (t = current_binding_level->blocks; t;)
1220 if (TREE_CHAIN (t) == block)
1221 TREE_CHAIN (t) = TREE_CHAIN (block);
1222 else
1223 t = TREE_CHAIN (t);
1225 TREE_CHAIN (block) = NULL;
1226 /* Clear TREE_USED which is always set by poplevel.
1227 The flag is set again if insert_block is called. */
1228 TREE_USED (block) = 0;
1231 /* Insert BLOCK at the end of the list of subblocks of the
1232 current binding level. This is used when a BIND_EXPR is expanded,
1233 to handle the BLOCK node inside the BIND_EXPR. */
1235 void
1236 insert_block (block)
1237 tree block;
1239 TREE_USED (block) = 1;
1240 current_binding_level->blocks
1241 = chainon (current_binding_level->blocks, block);
1244 /* Set the BLOCK node for the innermost scope
1245 (the one we are currently in). */
1247 void
1248 set_block (block)
1249 register tree block;
1251 current_binding_level->this_block = block;
1252 current_binding_level->names = chainon (current_binding_level->names,
1253 BLOCK_VARS (block));
1254 current_binding_level->blocks = chainon (current_binding_level->blocks,
1255 BLOCK_SUBBLOCKS (block));
1258 void
1259 push_label_level ()
1261 register struct binding_level *newlevel;
1263 /* Reuse or create a struct for this binding level. */
1265 if (free_binding_level)
1267 newlevel = free_binding_level;
1268 free_binding_level = free_binding_level->level_chain;
1270 else
1272 newlevel = make_binding_level ();
1275 /* Add this level to the front of the chain (stack) of label levels. */
1277 newlevel->level_chain = label_level_chain;
1278 label_level_chain = newlevel;
1280 newlevel->names = named_labels;
1281 newlevel->shadowed = shadowed_labels;
1282 named_labels = 0;
1283 shadowed_labels = 0;
1286 void
1287 pop_label_level ()
1289 register struct binding_level *level = label_level_chain;
1290 tree link, prev;
1292 /* Clear out the definitions of the declared labels in this level.
1293 Leave in the list any ordinary, non-declared labels. */
1294 for (link = named_labels, prev = 0; link;)
1296 if (C_DECLARED_LABEL_FLAG (TREE_VALUE (link)))
1298 if (DECL_SOURCE_LINE (TREE_VALUE (link)) == 0)
1300 error_with_decl (TREE_VALUE (link),
1301 "label `%s' used but not defined");
1302 /* Avoid crashing later. */
1303 define_label (input_filename, lineno,
1304 DECL_NAME (TREE_VALUE (link)));
1306 else if (warn_unused_label && !TREE_USED (TREE_VALUE (link)))
1307 warning_with_decl (TREE_VALUE (link),
1308 "label `%s' defined but not used");
1309 IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link))) = 0;
1311 /* Delete this element from the list. */
1312 link = TREE_CHAIN (link);
1313 if (prev)
1314 TREE_CHAIN (prev) = link;
1315 else
1316 named_labels = link;
1318 else
1320 prev = link;
1321 link = TREE_CHAIN (link);
1325 /* Bring back all the labels that were shadowed. */
1326 for (link = shadowed_labels; link; link = TREE_CHAIN (link))
1327 if (DECL_NAME (TREE_VALUE (link)) != 0)
1328 IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link)))
1329 = TREE_VALUE (link);
1331 named_labels = chainon (named_labels, level->names);
1332 shadowed_labels = level->shadowed;
1334 /* Pop the current level, and free the structure for reuse. */
1335 label_level_chain = label_level_chain->level_chain;
1336 level->level_chain = free_binding_level;
1337 free_binding_level = level;
1340 /* Push a definition or a declaration of struct, union or enum tag "name".
1341 "type" should be the type node.
1342 We assume that the tag "name" is not already defined.
1344 Note that the definition may really be just a forward reference.
1345 In that case, the TYPE_SIZE will be zero. */
1347 void
1348 pushtag (name, type)
1349 tree name, type;
1351 register struct binding_level *b;
1353 /* Find the proper binding level for this type tag. */
1355 for (b = current_binding_level; b->tag_transparent; b = b->level_chain)
1356 continue;
1358 if (name)
1360 /* Record the identifier as the type's name if it has none. */
1362 if (TYPE_NAME (type) == 0)
1363 TYPE_NAME (type) = name;
1366 b->tags = tree_cons (name, type, b->tags);
1368 /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
1369 tagged type we just added to the current binding level. This fake
1370 NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
1371 to output a representation of a tagged type, and it also gives
1372 us a convenient place to record the "scope start" address for the
1373 tagged type. */
1375 TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));
1377 /* An approximation for now, so we can tell this is a function-scope tag.
1378 This will be updated in poplevel. */
1379 TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
1382 /* Handle when a new declaration NEWDECL
1383 has the same name as an old one OLDDECL
1384 in the same binding contour.
1385 Prints an error message if appropriate.
1387 If safely possible, alter OLDDECL to look like NEWDECL, and return 1.
1388 Otherwise, return 0.
1390 When DIFFERENT_BINDING_LEVEL is true, NEWDECL is an external declaration,
1391 and OLDDECL is in an outer binding level and should thus not be changed. */
1393 static int
1394 duplicate_decls (newdecl, olddecl, different_binding_level)
1395 register tree newdecl, olddecl;
1396 int different_binding_level;
1398 int types_match = comptypes (TREE_TYPE (newdecl), TREE_TYPE (olddecl));
1399 int new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
1400 && DECL_INITIAL (newdecl) != 0);
1401 tree oldtype = TREE_TYPE (olddecl);
1402 tree newtype = TREE_TYPE (newdecl);
1403 int errmsg = 0;
1405 if (DECL_P (olddecl))
1406 DECL_MACHINE_ATTRIBUTES (newdecl)
1407 = (*targetm.merge_decl_attributes) (olddecl, newdecl);
1409 if (TREE_CODE (newtype) == ERROR_MARK
1410 || TREE_CODE (oldtype) == ERROR_MARK)
1411 types_match = 0;
1413 /* New decl is completely inconsistent with the old one =>
1414 tell caller to replace the old one.
1415 This is always an error except in the case of shadowing a builtin. */
1416 if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1418 if (TREE_CODE (olddecl) == FUNCTION_DECL
1419 && (DECL_BUILT_IN (olddecl)
1420 || DECL_BUILT_IN_NONANSI (olddecl)))
1422 /* If you declare a built-in or predefined function name as static,
1423 the old definition is overridden,
1424 but optionally warn this was a bad choice of name. */
1425 if (!TREE_PUBLIC (newdecl))
1427 if (!warn_shadow)
1429 else if (DECL_BUILT_IN (olddecl))
1430 warning_with_decl (newdecl, "shadowing built-in function `%s'");
1431 else
1432 warning_with_decl (newdecl, "shadowing library function `%s'");
1434 /* Likewise, if the built-in is not ansi, then programs can
1435 override it even globally without an error. */
1436 else if (! DECL_BUILT_IN (olddecl))
1437 warning_with_decl (newdecl,
1438 "library function `%s' declared as non-function");
1440 else if (DECL_BUILT_IN_NONANSI (olddecl))
1441 warning_with_decl (newdecl,
1442 "built-in function `%s' declared as non-function");
1443 else
1444 warning_with_decl (newdecl,
1445 "built-in function `%s' declared as non-function");
1447 else
1449 error_with_decl (newdecl, "`%s' redeclared as different kind of symbol");
1450 error_with_decl (olddecl, "previous declaration of `%s'");
1453 return 0;
1456 /* For real parm decl following a forward decl,
1457 return 1 so old decl will be reused. */
1458 if (types_match && TREE_CODE (newdecl) == PARM_DECL
1459 && TREE_ASM_WRITTEN (olddecl) && ! TREE_ASM_WRITTEN (newdecl))
1460 return 1;
1462 /* The new declaration is the same kind of object as the old one.
1463 The declarations may partially match. Print warnings if they don't
1464 match enough. Ultimately, copy most of the information from the new
1465 decl to the old one, and keep using the old one. */
1467 if (flag_traditional && TREE_CODE (newdecl) == FUNCTION_DECL
1468 && IDENTIFIER_IMPLICIT_DECL (DECL_NAME (newdecl)) == olddecl
1469 && DECL_INITIAL (olddecl) == 0)
1470 /* If -traditional, avoid error for redeclaring fcn
1471 after implicit decl. */
1473 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1474 && DECL_BUILT_IN (olddecl))
1476 /* A function declaration for a built-in function. */
1477 if (!TREE_PUBLIC (newdecl))
1479 /* If you declare a built-in function name as static, the
1480 built-in definition is overridden,
1481 but optionally warn this was a bad choice of name. */
1482 if (warn_shadow)
1483 warning_with_decl (newdecl, "shadowing built-in function `%s'");
1484 /* Discard the old built-in function. */
1485 return 0;
1487 else if (!types_match)
1489 /* Accept the return type of the new declaration if same modes. */
1490 tree oldreturntype = TREE_TYPE (oldtype);
1491 tree newreturntype = TREE_TYPE (newtype);
1493 if (TYPE_MODE (oldreturntype) == TYPE_MODE (newreturntype))
1495 /* Function types may be shared, so we can't just modify
1496 the return type of olddecl's function type. */
1497 tree trytype
1498 = build_function_type (newreturntype,
1499 TYPE_ARG_TYPES (oldtype));
1501 types_match = comptypes (newtype, trytype);
1502 if (types_match)
1503 oldtype = trytype;
1505 /* Accept harmless mismatch in first argument type also.
1506 This is for the ffs and fprintf builtins. */
1507 if (TYPE_ARG_TYPES (TREE_TYPE (newdecl)) != 0
1508 && TYPE_ARG_TYPES (oldtype) != 0
1509 && TREE_VALUE (TYPE_ARG_TYPES (newtype)) != 0
1510 && TREE_VALUE (TYPE_ARG_TYPES (oldtype)) != 0
1511 && (TYPE_MODE (TREE_VALUE (TYPE_ARG_TYPES (newtype)))
1512 == TYPE_MODE (TREE_VALUE (TYPE_ARG_TYPES (oldtype)))))
1514 /* Function types may be shared, so we can't just modify
1515 the return type of olddecl's function type. */
1516 tree trytype
1517 = build_function_type (TREE_TYPE (oldtype),
1518 tree_cons (NULL_TREE,
1519 TREE_VALUE (TYPE_ARG_TYPES (newtype)),
1520 TREE_CHAIN (TYPE_ARG_TYPES (oldtype))));
1522 types_match = comptypes (newtype, trytype);
1523 if (types_match)
1524 oldtype = trytype;
1526 if (! different_binding_level)
1527 TREE_TYPE (olddecl) = oldtype;
1529 if (!types_match)
1531 /* If types don't match for a built-in, throw away the built-in. */
1532 warning_with_decl (newdecl, "conflicting types for built-in function `%s'");
1533 return 0;
1536 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1537 && DECL_SOURCE_LINE (olddecl) == 0)
1539 /* A function declaration for a predeclared function
1540 that isn't actually built in. */
1541 if (!TREE_PUBLIC (newdecl))
1543 /* If you declare it as static, the
1544 default definition is overridden. */
1545 return 0;
1547 else if (!types_match)
1549 /* If the types don't match, preserve volatility indication.
1550 Later on, we will discard everything else about the
1551 default declaration. */
1552 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1555 /* Permit char *foo () to match void *foo (...) if not pedantic,
1556 if one of them came from a system header file. */
1557 else if (!types_match
1558 && TREE_CODE (olddecl) == FUNCTION_DECL
1559 && TREE_CODE (newdecl) == FUNCTION_DECL
1560 && TREE_CODE (TREE_TYPE (oldtype)) == POINTER_TYPE
1561 && TREE_CODE (TREE_TYPE (newtype)) == POINTER_TYPE
1562 && (DECL_IN_SYSTEM_HEADER (olddecl)
1563 || DECL_IN_SYSTEM_HEADER (newdecl))
1564 && ((TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (newtype))) == void_type_node
1565 && TYPE_ARG_TYPES (oldtype) == 0
1566 && self_promoting_args_p (TYPE_ARG_TYPES (newtype))
1567 && TREE_TYPE (TREE_TYPE (oldtype)) == char_type_node)
1569 (TREE_TYPE (TREE_TYPE (newtype)) == char_type_node
1570 && TYPE_ARG_TYPES (newtype) == 0
1571 && self_promoting_args_p (TYPE_ARG_TYPES (oldtype))
1572 && TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)))
1574 if (pedantic)
1575 pedwarn_with_decl (newdecl, "conflicting types for `%s'");
1576 /* Make sure we keep void * as ret type, not char *. */
1577 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (oldtype))) == void_type_node)
1578 TREE_TYPE (newdecl) = newtype = oldtype;
1580 /* Set DECL_IN_SYSTEM_HEADER, so that if we see another declaration
1581 we will come back here again. */
1582 DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1584 else if (!types_match
1585 /* Permit char *foo (int, ...); followed by char *foo ();
1586 if not pedantic. */
1587 && ! (TREE_CODE (olddecl) == FUNCTION_DECL
1588 && ! pedantic
1589 /* Return types must still match. */
1590 && comptypes (TREE_TYPE (oldtype),
1591 TREE_TYPE (newtype))
1592 && TYPE_ARG_TYPES (newtype) == 0))
1594 error_with_decl (newdecl, "conflicting types for `%s'");
1595 /* Check for function type mismatch
1596 involving an empty arglist vs a nonempty one. */
1597 if (TREE_CODE (olddecl) == FUNCTION_DECL
1598 && comptypes (TREE_TYPE (oldtype),
1599 TREE_TYPE (newtype))
1600 && ((TYPE_ARG_TYPES (oldtype) == 0
1601 && DECL_INITIAL (olddecl) == 0)
1603 (TYPE_ARG_TYPES (newtype) == 0
1604 && DECL_INITIAL (newdecl) == 0)))
1606 /* Classify the problem further. */
1607 register tree t = TYPE_ARG_TYPES (oldtype);
1608 if (t == 0)
1609 t = TYPE_ARG_TYPES (newtype);
1610 for (; t; t = TREE_CHAIN (t))
1612 register tree type = TREE_VALUE (t);
1614 if (TREE_CHAIN (t) == 0
1615 && TYPE_MAIN_VARIANT (type) != void_type_node)
1617 error ("A parameter list with an ellipsis can't match an empty parameter name list declaration.");
1618 break;
1621 if (simple_type_promotes_to (type) != NULL_TREE)
1623 error ("An argument type that has a default promotion can't match an empty parameter name list declaration.");
1624 break;
1628 error_with_decl (olddecl, "previous declaration of `%s'");
1630 else
1632 errmsg = redeclaration_error_message (newdecl, olddecl);
1633 if (errmsg)
1635 switch (errmsg)
1637 case 1:
1638 error_with_decl (newdecl, "redefinition of `%s'");
1639 break;
1640 case 2:
1641 error_with_decl (newdecl, "redeclaration of `%s'");
1642 break;
1643 case 3:
1644 error_with_decl (newdecl, "conflicting declarations of `%s'");
1645 break;
1646 default:
1647 abort ();
1650 error_with_decl (olddecl,
1651 ((DECL_INITIAL (olddecl)
1652 && current_binding_level == global_binding_level)
1653 ? "`%s' previously defined here"
1654 : "`%s' previously declared here"));
1656 else if (TREE_CODE (newdecl) == TYPE_DECL
1657 && (DECL_IN_SYSTEM_HEADER (olddecl)
1658 || DECL_IN_SYSTEM_HEADER (newdecl)))
1660 warning_with_decl (newdecl, "redefinition of `%s'");
1661 warning_with_decl
1662 (olddecl,
1663 ((DECL_INITIAL (olddecl)
1664 && current_binding_level == global_binding_level)
1665 ? "`%s' previously defined here"
1666 : "`%s' previously declared here"));
1668 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1669 && DECL_INITIAL (olddecl) != 0
1670 && TYPE_ARG_TYPES (oldtype) == 0
1671 && TYPE_ARG_TYPES (newtype) != 0
1672 && TYPE_ACTUAL_ARG_TYPES (oldtype) != 0)
1674 register tree type, parm;
1675 register int nargs;
1676 /* Prototype decl follows defn w/o prototype. */
1678 for (parm = TYPE_ACTUAL_ARG_TYPES (oldtype),
1679 type = TYPE_ARG_TYPES (newtype),
1680 nargs = 1;
1682 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type), nargs++)
1684 if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
1685 && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
1687 warning_with_decl (newdecl, "prototype for `%s' follows");
1688 warning_with_decl (olddecl, "non-prototype definition here");
1689 break;
1691 if (TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == void_type_node
1692 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
1694 error_with_decl (newdecl,
1695 "prototype for `%s' follows and number of arguments doesn't match");
1696 error_with_decl (olddecl, "non-prototype definition here");
1697 errmsg = 1;
1698 break;
1700 /* Type for passing arg must be consistent
1701 with that declared for the arg. */
1702 if (! comptypes (TREE_VALUE (parm), TREE_VALUE (type))
1703 /* If -traditional, allow `unsigned int' instead of `int'
1704 in the prototype. */
1705 && (! (flag_traditional
1706 && TYPE_MAIN_VARIANT (TREE_VALUE (parm)) == integer_type_node
1707 && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == unsigned_type_node)))
1709 error_with_decl (newdecl,
1710 "prototype for `%s' follows and argument %d doesn't match",
1711 nargs);
1712 error_with_decl (olddecl, "non-prototype definition here");
1713 errmsg = 1;
1714 break;
1718 /* Warn about mismatches in various flags. */
1719 else
1721 /* Warn if function is now inline
1722 but was previously declared not inline and has been called. */
1723 if (TREE_CODE (olddecl) == FUNCTION_DECL
1724 && ! DECL_INLINE (olddecl) && DECL_INLINE (newdecl)
1725 && TREE_USED (olddecl))
1726 warning_with_decl (newdecl,
1727 "`%s' declared inline after being called");
1728 if (TREE_CODE (olddecl) == FUNCTION_DECL
1729 && ! DECL_INLINE (olddecl) && DECL_INLINE (newdecl)
1730 && DECL_INITIAL (olddecl) != 0)
1731 warning_with_decl (newdecl,
1732 "`%s' declared inline after its definition");
1734 /* If pedantic, warn when static declaration follows a non-static
1735 declaration. Otherwise, do so only for functions. */
1736 if ((pedantic || TREE_CODE (olddecl) == FUNCTION_DECL)
1737 && TREE_PUBLIC (olddecl)
1738 && !TREE_PUBLIC (newdecl))
1739 warning_with_decl (newdecl, "static declaration for `%s' follows non-static");
1741 /* If warn_traditional, warn when a non-static function
1742 declaration follows a static one. */
1743 if (warn_traditional && !in_system_header
1744 && TREE_CODE (olddecl) == FUNCTION_DECL
1745 && !TREE_PUBLIC (olddecl)
1746 && TREE_PUBLIC (newdecl))
1747 warning_with_decl (newdecl, "non-static declaration for `%s' follows static");
1749 /* Warn when const declaration follows a non-const
1750 declaration, but not for functions. */
1751 if (TREE_CODE (olddecl) != FUNCTION_DECL
1752 && !TREE_READONLY (olddecl)
1753 && TREE_READONLY (newdecl))
1754 warning_with_decl (newdecl, "const declaration for `%s' follows non-const");
1755 /* These bits are logically part of the type, for variables.
1756 But not for functions
1757 (where qualifiers are not valid ANSI anyway). */
1758 else if (pedantic && TREE_CODE (olddecl) != FUNCTION_DECL
1759 && (TREE_READONLY (newdecl) != TREE_READONLY (olddecl)
1760 || TREE_THIS_VOLATILE (newdecl) != TREE_THIS_VOLATILE (olddecl)))
1761 pedwarn_with_decl (newdecl, "type qualifiers for `%s' conflict with previous decl");
1765 /* Optionally warn about more than one declaration for the same name. */
1766 if (errmsg == 0 && warn_redundant_decls && DECL_SOURCE_LINE (olddecl) != 0
1767 /* Don't warn about a function declaration
1768 followed by a definition. */
1769 && !(TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl) != 0
1770 && DECL_INITIAL (olddecl) == 0)
1771 /* Don't warn about extern decl followed by (tentative) definition. */
1772 && !(DECL_EXTERNAL (olddecl) && ! DECL_EXTERNAL (newdecl)))
1774 warning_with_decl (newdecl, "redundant redeclaration of `%s' in same scope");
1775 warning_with_decl (olddecl, "previous declaration of `%s'");
1778 /* Copy all the DECL_... slots specified in the new decl
1779 except for any that we copy here from the old type.
1781 Past this point, we don't change OLDTYPE and NEWTYPE
1782 even if we change the types of NEWDECL and OLDDECL. */
1784 if (types_match)
1786 /* When copying info to olddecl, we store into write_olddecl
1787 instead. This allows us to avoid modifying olddecl when
1788 different_binding_level is true. */
1789 tree write_olddecl = different_binding_level ? newdecl : olddecl;
1791 /* Merge the data types specified in the two decls. */
1792 if (TREE_CODE (newdecl) != FUNCTION_DECL || !DECL_BUILT_IN (olddecl))
1794 if (different_binding_level)
1796 if (TYPE_ARG_TYPES (oldtype) != 0
1797 && TYPE_ARG_TYPES (newtype) == 0)
1798 TREE_TYPE (newdecl) = common_type (newtype, oldtype);
1799 else
1800 TREE_TYPE (newdecl)
1801 = build_type_attribute_variant
1802 (newtype,
1803 merge_attributes (TYPE_ATTRIBUTES (newtype),
1804 TYPE_ATTRIBUTES (oldtype)));
1806 else
1807 TREE_TYPE (newdecl)
1808 = TREE_TYPE (olddecl)
1809 = common_type (newtype, oldtype);
1812 /* Lay the type out, unless already done. */
1813 if (oldtype != TREE_TYPE (newdecl))
1815 if (TREE_TYPE (newdecl) != error_mark_node)
1816 layout_type (TREE_TYPE (newdecl));
1817 if (TREE_CODE (newdecl) != FUNCTION_DECL
1818 && TREE_CODE (newdecl) != TYPE_DECL
1819 && TREE_CODE (newdecl) != CONST_DECL)
1820 layout_decl (newdecl, 0);
1822 else
1824 /* Since the type is OLDDECL's, make OLDDECL's size go with. */
1825 DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
1826 DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
1827 DECL_MODE (newdecl) = DECL_MODE (olddecl);
1828 if (TREE_CODE (olddecl) != FUNCTION_DECL)
1829 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
1831 DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
1832 DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
1836 /* Keep the old rtl since we can safely use it. */
1837 COPY_DECL_RTL (olddecl, newdecl);
1839 /* Merge the type qualifiers. */
1840 if (TREE_CODE (olddecl) == FUNCTION_DECL
1841 && DECL_BUILT_IN_NONANSI (olddecl) && TREE_THIS_VOLATILE (olddecl)
1842 && ! TREE_THIS_VOLATILE (newdecl))
1843 TREE_THIS_VOLATILE (write_olddecl) = 0;
1845 if (TREE_READONLY (newdecl))
1846 TREE_READONLY (write_olddecl) = 1;
1848 if (TREE_THIS_VOLATILE (newdecl))
1850 TREE_THIS_VOLATILE (write_olddecl) = 1;
1851 if (TREE_CODE (newdecl) == VAR_DECL
1852 /* If an automatic variable is re-declared in the same
1853 function scope, but the old declaration was not
1854 volatile, make_var_volatile() would crash because the
1855 variable would have been assigned to a pseudo, not a
1856 MEM. Since this duplicate declaration is invalid
1857 anyway, we just skip the call. */
1858 && errmsg == 0)
1859 make_var_volatile (newdecl);
1862 /* Keep source location of definition rather than declaration. */
1863 /* When called with different_binding_level set, keep the old
1864 information so that meaningful diagnostics can be given. */
1865 if (DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0
1866 && ! different_binding_level)
1868 DECL_SOURCE_LINE (newdecl) = DECL_SOURCE_LINE (olddecl);
1869 DECL_SOURCE_FILE (newdecl) = DECL_SOURCE_FILE (olddecl);
1872 /* Merge the unused-warning information. */
1873 if (DECL_IN_SYSTEM_HEADER (olddecl))
1874 DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1875 else if (DECL_IN_SYSTEM_HEADER (newdecl))
1876 DECL_IN_SYSTEM_HEADER (write_olddecl) = 1;
1878 /* Merge the initialization information. */
1879 /* When called with different_binding_level set, don't copy over
1880 DECL_INITIAL, so that we don't accidentally change function
1881 declarations into function definitions. */
1882 if (DECL_INITIAL (newdecl) == 0 && ! different_binding_level)
1883 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1885 /* Merge the section attribute.
1886 We want to issue an error if the sections conflict but that must be
1887 done later in decl_attributes since we are called before attributes
1888 are assigned. */
1889 if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
1890 DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
1892 /* Copy the assembler name.
1893 Currently, it can only be defined in the prototype. */
1894 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
1896 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1898 DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
1899 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1901 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
1902 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
1903 DECL_NO_CHECK_MEMORY_USAGE (newdecl)
1904 |= DECL_NO_CHECK_MEMORY_USAGE (olddecl);
1905 DECL_NO_LIMIT_STACK (newdecl)
1906 |= DECL_NO_LIMIT_STACK (olddecl);
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)
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);
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)
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;
1934 if (DECL_EXTERNAL (newdecl))
1936 if (! different_binding_level)
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);
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);
1949 else
1951 TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
1952 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1955 if (TREE_CODE (newdecl) == FUNCTION_DECL)
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))
1963 note_outlining_of_inline_function (olddecl);
1965 /* The new defn must not be inline. */
1966 DECL_INLINE (newdecl) = 0;
1967 DECL_UNINLINABLE (newdecl) = 1;
1969 else
1971 /* If either decl says `inline', this fn is inline,
1972 unless its definition was passed already. */
1973 if (DECL_INLINE (newdecl) && DECL_INITIAL (olddecl) == 0)
1974 DECL_INLINE (olddecl) = 1;
1976 DECL_INLINE (newdecl) = DECL_INLINE (olddecl);
1979 if (DECL_BUILT_IN (olddecl))
1981 /* Get rid of any built-in function if new arg types don't match it
1982 or if we have a function definition. */
1983 if (! types_match || new_is_definition)
1985 if (! different_binding_level)
1987 TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
1988 DECL_BUILT_IN_CLASS (olddecl) = NOT_BUILT_IN;
1991 else
1993 /* If redeclaring a builtin function, and not a definition,
1994 it stays built in. */
1995 DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
1996 DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
1999 /* Also preserve various other info from the definition. */
2000 else if (! new_is_definition)
2001 DECL_NUM_STMTS (newdecl) = DECL_NUM_STMTS (olddecl);
2002 if (! new_is_definition)
2004 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
2005 /* When called with different_binding_level set, don't copy over
2006 DECL_INITIAL, so that we don't accidentally change function
2007 declarations into function definitions. */
2008 if (! different_binding_level)
2009 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
2010 DECL_SAVED_INSNS (newdecl) = DECL_SAVED_INSNS (olddecl);
2011 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
2012 if (DECL_INLINE (newdecl))
2013 DECL_ABSTRACT_ORIGIN (newdecl) = DECL_ABSTRACT_ORIGIN (olddecl);
2016 if (different_binding_level)
2017 return 0;
2019 /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
2020 But preserve OLDDECL's DECL_UID. */
2022 register unsigned olddecl_uid = DECL_UID (olddecl);
2024 memcpy ((char *) olddecl + sizeof (struct tree_common),
2025 (char *) newdecl + sizeof (struct tree_common),
2026 sizeof (struct tree_decl) - sizeof (struct tree_common));
2027 DECL_UID (olddecl) = olddecl_uid;
2030 /* NEWDECL contains the merged attribute lists.
2031 Update OLDDECL to be the same. */
2032 DECL_MACHINE_ATTRIBUTES (olddecl) = DECL_MACHINE_ATTRIBUTES (newdecl);
2034 return 1;
2037 /* Record a decl-node X as belonging to the current lexical scope.
2038 Check for errors (such as an incompatible declaration for the same
2039 name already seen in the same scope).
2041 Returns either X or an old decl for the same name.
2042 If an old decl is returned, it may have been smashed
2043 to agree with what X says. */
2045 tree
2046 pushdecl (x)
2047 tree x;
2049 register tree t;
2050 register tree name = DECL_NAME (x);
2051 register struct binding_level *b = current_binding_level;
2053 DECL_CONTEXT (x) = current_function_decl;
2054 /* A local extern declaration for a function doesn't constitute nesting.
2055 A local auto declaration does, since it's a forward decl
2056 for a nested function coming later. */
2057 if ((TREE_CODE (x) == FUNCTION_DECL || TREE_CODE (x) == VAR_DECL)
2058 && DECL_INITIAL (x) == 0 && DECL_EXTERNAL (x))
2059 DECL_CONTEXT (x) = 0;
2061 if (warn_nested_externs && DECL_EXTERNAL (x) && b != global_binding_level
2062 && x != IDENTIFIER_IMPLICIT_DECL (name)
2063 /* Don't print error messages for __FUNCTION__ and __PRETTY_FUNCTION__ */
2064 && !DECL_IN_SYSTEM_HEADER (x))
2065 warning ("nested extern declaration of `%s'", IDENTIFIER_POINTER (name));
2067 if (name)
2069 const char *file;
2070 int line;
2071 int different_binding_level = 0;
2073 t = lookup_name_current_level (name);
2074 /* Don't type check externs here when -traditional. This is so that
2075 code with conflicting declarations inside blocks will get warnings
2076 not errors. X11 for instance depends on this. */
2077 if (! t && DECL_EXTERNAL (x) && TREE_PUBLIC (x) && ! flag_traditional)
2079 t = IDENTIFIER_GLOBAL_VALUE (name);
2080 /* Type decls at global scope don't conflict with externs declared
2081 inside lexical blocks. */
2082 if (t && TREE_CODE (t) == TYPE_DECL)
2083 t = 0;
2084 different_binding_level = 1;
2086 if (t != 0 && t == error_mark_node)
2087 /* error_mark_node is 0 for a while during initialization! */
2089 t = 0;
2090 error_with_decl (x, "`%s' used prior to declaration");
2093 if (t != 0)
2095 file = DECL_SOURCE_FILE (t);
2096 line = DECL_SOURCE_LINE (t);
2099 /* If this decl is `static' and an implicit decl was seen previously,
2100 warn. But don't complain if -traditional,
2101 since traditional compilers don't complain. */
2102 if (! flag_traditional && TREE_PUBLIC (name)
2103 /* Don't test for DECL_EXTERNAL, because grokdeclarator
2104 sets this for all functions. */
2105 && ! TREE_PUBLIC (x)
2106 && (TREE_CODE (x) == FUNCTION_DECL || b == global_binding_level)
2107 /* We used to warn also for explicit extern followed by static,
2108 but sometimes you need to do it that way. */
2109 && IDENTIFIER_IMPLICIT_DECL (name) != 0)
2111 pedwarn ("`%s' was declared implicitly `extern' and later `static'",
2112 IDENTIFIER_POINTER (name));
2113 pedwarn_with_file_and_line
2114 (DECL_SOURCE_FILE (IDENTIFIER_IMPLICIT_DECL (name)),
2115 DECL_SOURCE_LINE (IDENTIFIER_IMPLICIT_DECL (name)),
2116 "previous declaration of `%s'",
2117 IDENTIFIER_POINTER (name));
2118 TREE_THIS_VOLATILE (name) = 1;
2121 if (t != 0 && duplicate_decls (x, t, different_binding_level))
2123 if (TREE_CODE (t) == PARM_DECL)
2125 /* Don't allow more than one "real" duplicate
2126 of a forward parm decl. */
2127 TREE_ASM_WRITTEN (t) = TREE_ASM_WRITTEN (x);
2128 return t;
2130 return t;
2133 /* If we are processing a typedef statement, generate a whole new
2134 ..._TYPE node (which will be just an variant of the existing
2135 ..._TYPE node with identical properties) and then install the
2136 TYPE_DECL node generated to represent the typedef name as the
2137 TYPE_NAME of this brand new (duplicate) ..._TYPE node.
2139 The whole point here is to end up with a situation where each
2140 and every ..._TYPE node the compiler creates will be uniquely
2141 associated with AT MOST one node representing a typedef name.
2142 This way, even though the compiler substitutes corresponding
2143 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
2144 early on, later parts of the compiler can always do the reverse
2145 translation and get back the corresponding typedef name. For
2146 example, given:
2148 typedef struct S MY_TYPE;
2149 MY_TYPE object;
2151 Later parts of the compiler might only know that `object' was of
2152 type `struct S' if it were not for code just below. With this
2153 code however, later parts of the compiler see something like:
2155 struct S' == struct S
2156 typedef struct S' MY_TYPE;
2157 struct S' object;
2159 And they can then deduce (from the node for type struct S') that
2160 the original object declaration was:
2162 MY_TYPE object;
2164 Being able to do this is important for proper support of protoize,
2165 and also for generating precise symbolic debugging information
2166 which takes full account of the programmer's (typedef) vocabulary.
2168 Obviously, we don't want to generate a duplicate ..._TYPE node if
2169 the TYPE_DECL node that we are now processing really represents a
2170 standard built-in type.
2172 Since all standard types are effectively declared at line zero
2173 in the source file, we can easily check to see if we are working
2174 on a standard type by checking the current value of lineno. */
2176 if (TREE_CODE (x) == TYPE_DECL)
2178 if (DECL_SOURCE_LINE (x) == 0)
2180 if (TYPE_NAME (TREE_TYPE (x)) == 0)
2181 TYPE_NAME (TREE_TYPE (x)) = x;
2183 else if (TREE_TYPE (x) != error_mark_node
2184 && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
2186 tree tt = TREE_TYPE (x);
2187 DECL_ORIGINAL_TYPE (x) = tt;
2188 tt = build_type_copy (tt);
2189 TYPE_NAME (tt) = x;
2190 TREE_USED (tt) = TREE_USED (x);
2191 TREE_TYPE (x) = tt;
2195 /* Multiple external decls of the same identifier ought to match.
2196 Check against both global declarations (when traditional) and out of
2197 scope (limbo) block level declarations.
2199 We get warnings about inline functions where they are defined.
2200 Avoid duplicate warnings where they are used. */
2201 if (TREE_PUBLIC (x)
2202 && ! (TREE_CODE (x) == FUNCTION_DECL && DECL_INLINE (x)))
2204 tree decl;
2206 if (flag_traditional && IDENTIFIER_GLOBAL_VALUE (name) != 0
2207 && (DECL_EXTERNAL (IDENTIFIER_GLOBAL_VALUE (name))
2208 || TREE_PUBLIC (IDENTIFIER_GLOBAL_VALUE (name))))
2209 decl = IDENTIFIER_GLOBAL_VALUE (name);
2210 else if (IDENTIFIER_LIMBO_VALUE (name) != 0)
2211 /* Decls in limbo are always extern, so no need to check that. */
2212 decl = IDENTIFIER_LIMBO_VALUE (name);
2213 else
2214 decl = 0;
2216 if (decl && ! comptypes (TREE_TYPE (x), TREE_TYPE (decl))
2217 /* If old decl is built-in, we already warned if we should. */
2218 && !DECL_BUILT_IN (decl))
2220 pedwarn_with_decl (x,
2221 "type mismatch with previous external decl");
2222 pedwarn_with_decl (decl, "previous external decl of `%s'");
2226 /* If a function has had an implicit declaration, and then is defined,
2227 make sure they are compatible. */
2229 if (IDENTIFIER_IMPLICIT_DECL (name) != 0
2230 && IDENTIFIER_GLOBAL_VALUE (name) == 0
2231 && TREE_CODE (x) == FUNCTION_DECL
2232 && ! comptypes (TREE_TYPE (x),
2233 TREE_TYPE (IDENTIFIER_IMPLICIT_DECL (name))))
2235 warning_with_decl (x, "type mismatch with previous implicit declaration");
2236 warning_with_decl (IDENTIFIER_IMPLICIT_DECL (name),
2237 "previous implicit declaration of `%s'");
2240 /* In PCC-compatibility mode, extern decls of vars with no current decl
2241 take effect at top level no matter where they are. */
2242 if (flag_traditional && DECL_EXTERNAL (x)
2243 && lookup_name (name) == 0)
2245 tree type = TREE_TYPE (x);
2247 /* But don't do this if the type contains temporary nodes. */
2248 while (type)
2250 if (type == error_mark_node)
2251 break;
2252 if (TYPE_CONTEXT (type))
2254 warning_with_decl (x, "type of external `%s' is not global");
2255 /* By exiting the loop early, we leave TYPE nonzero,
2256 and thus prevent globalization of the decl. */
2257 break;
2259 else if (TREE_CODE (type) == FUNCTION_TYPE
2260 && TYPE_ARG_TYPES (type) != 0)
2261 /* The types might not be truly local,
2262 but the list of arg types certainly is temporary.
2263 Since prototypes are nontraditional,
2264 ok not to do the traditional thing. */
2265 break;
2266 type = TREE_TYPE (type);
2269 if (type == 0)
2270 b = global_binding_level;
2273 /* This name is new in its binding level.
2274 Install the new declaration and return it. */
2275 if (b == global_binding_level)
2277 /* Install a global value. */
2279 /* If the first global decl has external linkage,
2280 warn if we later see static one. */
2281 if (IDENTIFIER_GLOBAL_VALUE (name) == 0 && TREE_PUBLIC (x))
2282 TREE_PUBLIC (name) = 1;
2284 IDENTIFIER_GLOBAL_VALUE (name) = x;
2286 /* We no longer care about any previous block level declarations. */
2287 IDENTIFIER_LIMBO_VALUE (name) = 0;
2289 /* Don't forget if the function was used via an implicit decl. */
2290 if (IDENTIFIER_IMPLICIT_DECL (name)
2291 && TREE_USED (IDENTIFIER_IMPLICIT_DECL (name)))
2292 TREE_USED (x) = 1, TREE_USED (name) = 1;
2294 /* Don't forget if its address was taken in that way. */
2295 if (IDENTIFIER_IMPLICIT_DECL (name)
2296 && TREE_ADDRESSABLE (IDENTIFIER_IMPLICIT_DECL (name)))
2297 TREE_ADDRESSABLE (x) = 1;
2299 /* Warn about mismatches against previous implicit decl. */
2300 if (IDENTIFIER_IMPLICIT_DECL (name) != 0
2301 /* If this real decl matches the implicit, don't complain. */
2302 && ! (TREE_CODE (x) == FUNCTION_DECL
2303 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (x)))
2304 == integer_type_node)))
2305 pedwarn ("`%s' was previously implicitly declared to return `int'",
2306 IDENTIFIER_POINTER (name));
2308 /* If this decl is `static' and an `extern' was seen previously,
2309 that is erroneous. */
2310 if (TREE_PUBLIC (name)
2311 && ! TREE_PUBLIC (x) && ! DECL_EXTERNAL (x))
2313 /* Okay to redeclare an ANSI built-in as static. */
2314 if (t != 0 && DECL_BUILT_IN (t))
2316 /* Okay to declare a non-ANSI built-in as anything. */
2317 else if (t != 0 && DECL_BUILT_IN_NONANSI (t))
2319 /* Okay to have global type decl after an earlier extern
2320 declaration inside a lexical block. */
2321 else if (TREE_CODE (x) == TYPE_DECL)
2323 else if (IDENTIFIER_IMPLICIT_DECL (name))
2325 if (! TREE_THIS_VOLATILE (name))
2326 pedwarn ("`%s' was declared implicitly `extern' and later `static'",
2327 IDENTIFIER_POINTER (name));
2329 else
2330 pedwarn ("`%s' was declared `extern' and later `static'",
2331 IDENTIFIER_POINTER (name));
2334 else
2336 /* Here to install a non-global value. */
2337 tree oldlocal = IDENTIFIER_LOCAL_VALUE (name);
2338 tree oldglobal = IDENTIFIER_GLOBAL_VALUE (name);
2340 IDENTIFIER_LOCAL_VALUE (name) = x;
2342 /* If this is an extern function declaration, see if we
2343 have a global definition or declaration for the function. */
2344 if (oldlocal == 0
2345 && oldglobal != 0
2346 && TREE_CODE (x) == FUNCTION_DECL
2347 && TREE_CODE (oldglobal) == FUNCTION_DECL
2348 && DECL_EXTERNAL (x) && ! DECL_INLINE (x))
2350 /* We have one. Their types must agree. */
2351 if (! comptypes (TREE_TYPE (x),
2352 TREE_TYPE (IDENTIFIER_GLOBAL_VALUE (name))))
2353 pedwarn_with_decl (x, "extern declaration of `%s' doesn't match global one");
2354 else
2356 /* Inner extern decl is inline if global one is.
2357 Copy enough to really inline it. */
2358 if (DECL_INLINE (oldglobal))
2360 DECL_INLINE (x) = DECL_INLINE (oldglobal);
2361 DECL_INITIAL (x) = (current_function_decl == oldglobal
2362 ? 0 : DECL_INITIAL (oldglobal));
2363 DECL_SAVED_INSNS (x) = DECL_SAVED_INSNS (oldglobal);
2364 DECL_NUM_STMTS (x) = DECL_NUM_STMTS (oldglobal);
2365 DECL_ARGUMENTS (x) = DECL_ARGUMENTS (oldglobal);
2366 DECL_RESULT (x) = DECL_RESULT (oldglobal);
2367 TREE_ASM_WRITTEN (x) = TREE_ASM_WRITTEN (oldglobal);
2368 DECL_ABSTRACT_ORIGIN (x)
2369 = DECL_ABSTRACT_ORIGIN (oldglobal);
2371 /* Inner extern decl is built-in if global one is. */
2372 if (DECL_BUILT_IN (oldglobal))
2374 DECL_BUILT_IN_CLASS (x) = DECL_BUILT_IN_CLASS (oldglobal);
2375 DECL_FUNCTION_CODE (x) = DECL_FUNCTION_CODE (oldglobal);
2377 /* Keep the arg types from a file-scope fcn defn. */
2378 if (TYPE_ARG_TYPES (TREE_TYPE (oldglobal)) != 0
2379 && DECL_INITIAL (oldglobal)
2380 && TYPE_ARG_TYPES (TREE_TYPE (x)) == 0)
2381 TREE_TYPE (x) = TREE_TYPE (oldglobal);
2385 #if 0
2386 /* This case is probably sometimes the right thing to do. */
2387 /* If we have a local external declaration,
2388 then any file-scope declaration should not
2389 have been static. */
2390 if (oldlocal == 0 && oldglobal != 0
2391 && !TREE_PUBLIC (oldglobal)
2392 && DECL_EXTERNAL (x) && TREE_PUBLIC (x))
2393 warning ("`%s' locally external but globally static",
2394 IDENTIFIER_POINTER (name));
2395 #endif
2397 /* If we have a local external declaration,
2398 and no file-scope declaration has yet been seen,
2399 then if we later have a file-scope decl it must not be static. */
2400 if (oldlocal == 0
2401 && DECL_EXTERNAL (x)
2402 && TREE_PUBLIC (x))
2404 if (oldglobal == 0)
2405 TREE_PUBLIC (name) = 1;
2407 /* Save this decl, so that we can do type checking against
2408 other decls after it falls out of scope.
2410 Only save it once. This prevents temporary decls created in
2411 expand_inline_function from being used here, since this
2412 will have been set when the inline function was parsed.
2413 It also helps give slightly better warnings. */
2414 if (IDENTIFIER_LIMBO_VALUE (name) == 0)
2415 IDENTIFIER_LIMBO_VALUE (name) = x;
2418 /* Warn if shadowing an argument at the top level of the body. */
2419 if (oldlocal != 0 && !DECL_EXTERNAL (x)
2420 /* This warning doesn't apply to the parms of a nested fcn. */
2421 && ! current_binding_level->parm_flag
2422 /* Check that this is one level down from the parms. */
2423 && current_binding_level->level_chain->parm_flag
2424 /* Check that the decl being shadowed
2425 comes from the parm level, one level up. */
2426 && chain_member (oldlocal, current_binding_level->level_chain->names))
2428 if (TREE_CODE (oldlocal) == PARM_DECL)
2429 pedwarn ("declaration of `%s' shadows a parameter",
2430 IDENTIFIER_POINTER (name));
2431 else
2432 pedwarn ("declaration of `%s' shadows a symbol from the parameter list",
2433 IDENTIFIER_POINTER (name));
2436 /* Maybe warn if shadowing something else. */
2437 else if (warn_shadow && !DECL_EXTERNAL (x)
2438 /* No shadow warnings for internally generated vars. */
2439 && DECL_SOURCE_LINE (x) != 0
2440 /* No shadow warnings for vars made for inlining. */
2441 && ! DECL_FROM_INLINE (x))
2443 const char *id = IDENTIFIER_POINTER (name);
2445 if (TREE_CODE (x) == PARM_DECL
2446 && current_binding_level->level_chain->parm_flag)
2447 /* Don't warn about the parm names in function declarator
2448 within a function declarator.
2449 It would be nice to avoid warning in any function
2450 declarator in a declaration, as opposed to a definition,
2451 but there is no way to tell it's not a definition. */
2453 else if (oldlocal != 0 && TREE_CODE (oldlocal) == PARM_DECL)
2454 warning ("declaration of `%s' shadows a parameter", id);
2455 else if (oldlocal != 0)
2456 warning ("declaration of `%s' shadows previous local", id);
2457 else if (IDENTIFIER_GLOBAL_VALUE (name) != 0
2458 && IDENTIFIER_GLOBAL_VALUE (name) != error_mark_node)
2459 warning ("declaration of `%s' shadows global declaration", id);
2462 /* If storing a local value, there may already be one (inherited).
2463 If so, record it for restoration when this binding level ends. */
2464 if (oldlocal != 0)
2465 b->shadowed = tree_cons (name, oldlocal, b->shadowed);
2468 /* Keep count of variables in this level with incomplete type.
2469 If the input is erroneous, we can have error_mark in the type
2470 slot (e.g. "f(void a, ...)") - that doesn't count as an
2471 incomplete type. */
2472 if (TREE_TYPE (x) != error_mark_node
2473 && !COMPLETE_TYPE_P (TREE_TYPE (x)))
2474 ++b->n_incomplete;
2477 /* Put decls on list in reverse order.
2478 We will reverse them later if necessary. */
2479 TREE_CHAIN (x) = b->names;
2480 b->names = x;
2482 return x;
2485 /* Like pushdecl, only it places X in GLOBAL_BINDING_LEVEL, if appropriate. */
2487 tree
2488 pushdecl_top_level (x)
2489 tree x;
2491 register tree t;
2492 register struct binding_level *b = current_binding_level;
2494 current_binding_level = global_binding_level;
2495 t = pushdecl (x);
2496 current_binding_level = b;
2497 return t;
2500 /* Generate an implicit declaration for identifier FUNCTIONID
2501 as a function of type int (). Print a warning if appropriate. */
2503 tree
2504 implicitly_declare (functionid)
2505 tree functionid;
2507 register tree decl;
2508 int traditional_warning = 0;
2509 /* Only one "implicit declaration" warning per identifier. */
2510 int implicit_warning;
2512 /* We used to reuse an old implicit decl here,
2513 but this loses with inline functions because it can clobber
2514 the saved decl chains. */
2515 #if 0
2516 if (IDENTIFIER_IMPLICIT_DECL (functionid) != 0)
2517 decl = IDENTIFIER_IMPLICIT_DECL (functionid);
2518 else
2519 #endif
2520 decl = build_decl (FUNCTION_DECL, functionid, default_function_type);
2522 /* Warn of implicit decl following explicit local extern decl.
2523 This is probably a program designed for traditional C. */
2524 if (TREE_PUBLIC (functionid) && IDENTIFIER_GLOBAL_VALUE (functionid) == 0)
2525 traditional_warning = 1;
2527 /* Warn once of an implicit declaration. */
2528 implicit_warning = (IDENTIFIER_IMPLICIT_DECL (functionid) == 0);
2530 DECL_EXTERNAL (decl) = 1;
2531 TREE_PUBLIC (decl) = 1;
2533 /* Record that we have an implicit decl and this is it. */
2534 IDENTIFIER_IMPLICIT_DECL (functionid) = decl;
2536 /* ANSI standard says implicit declarations are in the innermost block.
2537 So we record the decl in the standard fashion.
2538 If flag_traditional is set, pushdecl does it top-level. */
2539 pushdecl (decl);
2541 /* This is a no-op in c-lang.c or something real in objc-actions.c. */
2542 maybe_objc_check_decl (decl);
2544 rest_of_decl_compilation (decl, NULL, 0, 0);
2546 if (implicit_warning)
2547 implicit_decl_warning (functionid);
2548 else if (warn_traditional && traditional_warning)
2549 warning ("function `%s' was previously declared within a block",
2550 IDENTIFIER_POINTER (functionid));
2552 /* Write a record describing this implicit function declaration to the
2553 prototypes file (if requested). */
2555 gen_aux_info_record (decl, 0, 1, 0);
2557 return decl;
2560 void
2561 implicit_decl_warning (id)
2562 tree id;
2564 const char *name = IDENTIFIER_POINTER (id);
2565 if (mesg_implicit_function_declaration == 2)
2566 error ("implicit declaration of function `%s'", name);
2567 else if (mesg_implicit_function_declaration == 1)
2568 warning ("implicit declaration of function `%s'", name);
2571 /* Return zero if the declaration NEWDECL is valid
2572 when the declaration OLDDECL (assumed to be for the same name)
2573 has already been seen.
2574 Otherwise return 1 if NEWDECL is a redefinition, 2 if it is a redeclaration,
2575 and 3 if it is a conflicting declaration. */
2577 static int
2578 redeclaration_error_message (newdecl, olddecl)
2579 tree newdecl, olddecl;
2581 if (TREE_CODE (newdecl) == TYPE_DECL)
2583 if (flag_traditional && TREE_TYPE (newdecl) == TREE_TYPE (olddecl))
2584 return 0;
2585 /* pushdecl creates distinct types for TYPE_DECLs by calling
2586 build_type_copy, so the above comparison generally fails. We do
2587 another test against the TYPE_MAIN_VARIANT of the olddecl, which
2588 is equivalent to what this code used to do before the build_type_copy
2589 call. The variant type distinction should not matter for traditional
2590 code, because it doesn't have type qualifiers. */
2591 if (flag_traditional
2592 && TYPE_MAIN_VARIANT (TREE_TYPE (olddecl)) == TREE_TYPE (newdecl))
2593 return 0;
2594 if (DECL_IN_SYSTEM_HEADER (olddecl) || DECL_IN_SYSTEM_HEADER (newdecl))
2595 return 0;
2596 return 1;
2598 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
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_INLINE (olddecl) && DECL_EXTERNAL (olddecl)
2608 && ! (DECL_INLINE (newdecl) && DECL_EXTERNAL (newdecl))))
2609 return 1;
2610 return 0;
2612 else if (DECL_CONTEXT (newdecl) == NULL_TREE)
2614 /* Objects declared at top level: */
2615 /* If at least one is a reference, it's ok. */
2616 if (DECL_EXTERNAL (newdecl) || DECL_EXTERNAL (olddecl))
2617 return 0;
2618 /* Reject two definitions. */
2619 if (DECL_INITIAL (olddecl) != 0 && DECL_INITIAL (newdecl) != 0)
2620 return 1;
2621 /* Now we have two tentative defs, or one tentative and one real def. */
2622 /* Insist that the linkage match. */
2623 if (TREE_PUBLIC (olddecl) != TREE_PUBLIC (newdecl))
2624 return 3;
2625 return 0;
2627 else if (current_binding_level->parm_flag
2628 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
2629 return 0;
2630 else
2632 /* Newdecl has block scope. If olddecl has block scope also, then
2633 reject two definitions, and reject a definition together with an
2634 external reference. Otherwise, it is OK, because newdecl must
2635 be an extern reference to olddecl. */
2636 if (!(DECL_EXTERNAL (newdecl) && DECL_EXTERNAL (olddecl))
2637 && DECL_CONTEXT (newdecl) == DECL_CONTEXT (olddecl))
2638 return 2;
2639 return 0;
2643 /* Get the LABEL_DECL corresponding to identifier ID as a label.
2644 Create one if none exists so far for the current function.
2645 This function is called for both label definitions and label references. */
2647 tree
2648 lookup_label (id)
2649 tree id;
2651 register tree decl = IDENTIFIER_LABEL_VALUE (id);
2653 if (current_function_decl == 0)
2655 error ("label %s referenced outside of any function",
2656 IDENTIFIER_POINTER (id));
2657 return 0;
2660 /* Use a label already defined or ref'd with this name. */
2661 if (decl != 0)
2663 /* But not if it is inherited and wasn't declared to be inheritable. */
2664 if (DECL_CONTEXT (decl) != current_function_decl
2665 && ! C_DECLARED_LABEL_FLAG (decl))
2666 return shadow_label (id);
2667 return decl;
2670 decl = build_decl (LABEL_DECL, id, void_type_node);
2672 /* A label not explicitly declared must be local to where it's ref'd. */
2673 DECL_CONTEXT (decl) = current_function_decl;
2675 DECL_MODE (decl) = VOIDmode;
2677 /* Say where one reference is to the label,
2678 for the sake of the error if it is not defined. */
2679 DECL_SOURCE_LINE (decl) = lineno;
2680 DECL_SOURCE_FILE (decl) = input_filename;
2682 IDENTIFIER_LABEL_VALUE (id) = decl;
2684 named_labels = tree_cons (NULL_TREE, decl, named_labels);
2686 return decl;
2689 /* Make a label named NAME in the current function,
2690 shadowing silently any that may be inherited from containing functions
2691 or containing scopes.
2693 Note that valid use, if the label being shadowed
2694 comes from another scope in the same function,
2695 requires calling declare_nonlocal_label right away. */
2697 tree
2698 shadow_label (name)
2699 tree name;
2701 register tree decl = IDENTIFIER_LABEL_VALUE (name);
2703 if (decl != 0)
2705 register tree dup;
2707 /* Check to make sure that the label hasn't already been declared
2708 at this label scope */
2709 for (dup = named_labels; dup; dup = TREE_CHAIN (dup))
2710 if (TREE_VALUE (dup) == decl)
2712 error ("duplicate label declaration `%s'",
2713 IDENTIFIER_POINTER (name));
2714 error_with_decl (TREE_VALUE (dup),
2715 "this is a previous declaration");
2716 /* Just use the previous declaration. */
2717 return lookup_label (name);
2720 shadowed_labels = tree_cons (NULL_TREE, decl, shadowed_labels);
2721 IDENTIFIER_LABEL_VALUE (name) = decl = 0;
2724 return lookup_label (name);
2727 /* Define a label, specifying the location in the source file.
2728 Return the LABEL_DECL node for the label, if the definition is valid.
2729 Otherwise return 0. */
2731 tree
2732 define_label (filename, line, name)
2733 const char *filename;
2734 int line;
2735 tree name;
2737 tree decl = lookup_label (name);
2739 /* If label with this name is known from an outer context, shadow it. */
2740 if (decl != 0 && DECL_CONTEXT (decl) != current_function_decl)
2742 shadowed_labels = tree_cons (NULL_TREE, decl, shadowed_labels);
2743 IDENTIFIER_LABEL_VALUE (name) = 0;
2744 decl = lookup_label (name);
2747 if (warn_traditional && !in_system_header && lookup_name (name))
2748 warning_with_file_and_line (filename, line,
2749 "traditional C lacks a separate namespace for labels, identifier `%s' conflicts",
2750 IDENTIFIER_POINTER (name));
2752 if (DECL_INITIAL (decl) != 0)
2754 error_with_file_and_line (filename, line, "duplicate label `%s'",
2755 IDENTIFIER_POINTER (name));
2756 return 0;
2758 else
2760 /* Mark label as having been defined. */
2761 DECL_INITIAL (decl) = error_mark_node;
2762 /* Say where in the source. */
2763 DECL_SOURCE_FILE (decl) = filename;
2764 DECL_SOURCE_LINE (decl) = line;
2765 return decl;
2769 /* Return the list of declarations of the current level.
2770 Note that this list is in reverse order unless/until
2771 you nreverse it; and when you do nreverse it, you must
2772 store the result back using `storedecls' or you will lose. */
2774 tree
2775 getdecls ()
2777 return current_binding_level->names;
2780 /* Return the list of type-tags (for structs, etc) of the current level. */
2782 tree
2783 gettags ()
2785 return current_binding_level->tags;
2788 /* Store the list of declarations of the current level.
2789 This is done for the parameter declarations of a function being defined,
2790 after they are modified in the light of any missing parameters. */
2792 static void
2793 storedecls (decls)
2794 tree decls;
2796 current_binding_level->names = decls;
2799 /* Similarly, store the list of tags of the current level. */
2801 static void
2802 storetags (tags)
2803 tree tags;
2805 current_binding_level->tags = tags;
2808 /* Given NAME, an IDENTIFIER_NODE,
2809 return the structure (or union or enum) definition for that name.
2810 Searches binding levels from BINDING_LEVEL up to the global level.
2811 If THISLEVEL_ONLY is nonzero, searches only the specified context
2812 (but skips any tag-transparent contexts to find one that is
2813 meaningful for tags).
2814 CODE says which kind of type the caller wants;
2815 it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
2816 If the wrong kind of type is found, an error is reported. */
2818 static tree
2819 lookup_tag (code, name, binding_level, thislevel_only)
2820 enum tree_code code;
2821 struct binding_level *binding_level;
2822 tree name;
2823 int thislevel_only;
2825 register struct binding_level *level;
2826 int thislevel = 1;
2828 for (level = binding_level; level; level = level->level_chain)
2830 register tree tail;
2831 for (tail = level->tags; tail; tail = TREE_CHAIN (tail))
2833 if (TREE_PURPOSE (tail) == name)
2835 if (TREE_CODE (TREE_VALUE (tail)) != code)
2837 /* Definition isn't the kind we were looking for. */
2838 pending_invalid_xref = name;
2839 pending_invalid_xref_file = input_filename;
2840 pending_invalid_xref_line = lineno;
2841 /* If in the same binding level as a declaration as a tag
2842 of a different type, this must not be allowed to
2843 shadow that tag, so give the error immediately.
2844 (For example, "struct foo; union foo;" is invalid.) */
2845 if (thislevel)
2846 pending_xref_error ();
2848 return TREE_VALUE (tail);
2851 if (! level->tag_transparent)
2853 if (thislevel_only)
2854 return NULL_TREE;
2855 thislevel = 0;
2858 return NULL_TREE;
2861 /* Print an error message now
2862 for a recent invalid struct, union or enum cross reference.
2863 We don't print them immediately because they are not invalid
2864 when used in the `struct foo;' construct for shadowing. */
2866 void
2867 pending_xref_error ()
2869 if (pending_invalid_xref != 0)
2870 error_with_file_and_line (pending_invalid_xref_file,
2871 pending_invalid_xref_line,
2872 "`%s' defined as wrong kind of tag",
2873 IDENTIFIER_POINTER (pending_invalid_xref));
2874 pending_invalid_xref = 0;
2877 /* Given a type, find the tag that was defined for it and return the tag name.
2878 Otherwise return 0. */
2880 static tree
2881 lookup_tag_reverse (type)
2882 tree type;
2884 register struct binding_level *level;
2886 for (level = current_binding_level; level; level = level->level_chain)
2888 register tree tail;
2889 for (tail = level->tags; tail; tail = TREE_CHAIN (tail))
2891 if (TREE_VALUE (tail) == type)
2892 return TREE_PURPOSE (tail);
2895 return NULL_TREE;
2898 /* Look up NAME in the current binding level and its superiors
2899 in the namespace of variables, functions and typedefs.
2900 Return a ..._DECL node of some kind representing its definition,
2901 or return 0 if it is undefined. */
2903 tree
2904 lookup_name (name)
2905 tree name;
2907 register tree val;
2909 if (current_binding_level != global_binding_level
2910 && IDENTIFIER_LOCAL_VALUE (name))
2911 val = IDENTIFIER_LOCAL_VALUE (name);
2912 else
2913 val = IDENTIFIER_GLOBAL_VALUE (name);
2914 return val;
2917 /* Similar to `lookup_name' but look only at current binding level. */
2919 tree
2920 lookup_name_current_level (name)
2921 tree name;
2923 register tree t;
2925 if (current_binding_level == global_binding_level)
2926 return IDENTIFIER_GLOBAL_VALUE (name);
2928 if (IDENTIFIER_LOCAL_VALUE (name) == 0)
2929 return 0;
2931 for (t = current_binding_level->names; t; t = TREE_CHAIN (t))
2932 if (DECL_NAME (t) == name)
2933 break;
2935 return t;
2938 /* Mark ARG for GC. */
2940 static void
2941 mark_binding_level (arg)
2942 void *arg;
2944 struct binding_level *level = *(struct binding_level **) arg;
2946 for (; level != 0; level = level->level_chain)
2948 ggc_mark_tree (level->names);
2949 ggc_mark_tree (level->tags);
2950 ggc_mark_tree (level->shadowed);
2951 ggc_mark_tree (level->blocks);
2952 ggc_mark_tree (level->this_block);
2953 ggc_mark_tree (level->parm_order);
2957 /* Create the predefined scalar types of C,
2958 and some nodes representing standard constants (0, 1, (void *) 0).
2959 Initialize the global binding level.
2960 Make definitions for built-in primitive functions. */
2962 void
2963 init_decl_processing ()
2965 register tree endlink;
2966 tree ptr_ftype_void, ptr_ftype_ptr;
2968 current_function_decl = NULL;
2969 named_labels = NULL;
2970 current_binding_level = NULL_BINDING_LEVEL;
2971 free_binding_level = NULL_BINDING_LEVEL;
2973 /* Make the binding_level structure for global names. */
2974 pushlevel (0);
2975 global_binding_level = current_binding_level;
2977 build_common_tree_nodes (flag_signed_char);
2979 c_common_nodes_and_builtins ();
2981 boolean_type_node = integer_type_node;
2982 boolean_true_node = integer_one_node;
2983 boolean_false_node = integer_zero_node;
2985 /* With GCC, C99's _Bool is always of size 1. */
2986 c_bool_type_node = make_unsigned_type (CHAR_TYPE_SIZE);
2987 TREE_SET_CODE (c_bool_type_node, BOOLEAN_TYPE);
2988 TYPE_MAX_VALUE (c_bool_type_node) = build_int_2 (1, 0);
2989 TREE_TYPE (TYPE_MAX_VALUE (c_bool_type_node)) = c_bool_type_node;
2990 TYPE_PRECISION (c_bool_type_node) = 1;
2991 pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
2992 c_bool_type_node));
2993 c_bool_false_node = build_int_2 (0, 0);
2994 TREE_TYPE (c_bool_false_node) = c_bool_type_node;
2995 c_bool_true_node = build_int_2 (1, 0);
2996 TREE_TYPE (c_bool_true_node) = c_bool_type_node;
2998 endlink = void_list_node;
2999 ptr_ftype_void = build_function_type (ptr_type_node, endlink);
3000 ptr_ftype_ptr
3001 = build_function_type (ptr_type_node,
3002 tree_cons (NULL_TREE, ptr_type_node, endlink));
3004 /* Types which are common to the fortran compiler and libf2c. When
3005 changing these, you also need to be concerned with f/com.h. */
3007 if (TYPE_PRECISION (float_type_node)
3008 == TYPE_PRECISION (long_integer_type_node))
3010 g77_integer_type_node = long_integer_type_node;
3011 g77_uinteger_type_node = long_unsigned_type_node;
3013 else if (TYPE_PRECISION (float_type_node)
3014 == TYPE_PRECISION (integer_type_node))
3016 g77_integer_type_node = integer_type_node;
3017 g77_uinteger_type_node = unsigned_type_node;
3019 else
3020 g77_integer_type_node = g77_uinteger_type_node = NULL_TREE;
3022 if (g77_integer_type_node != NULL_TREE)
3024 pushdecl (build_decl (TYPE_DECL, get_identifier ("__g77_integer"),
3025 g77_integer_type_node));
3026 pushdecl (build_decl (TYPE_DECL, get_identifier ("__g77_uinteger"),
3027 g77_uinteger_type_node));
3030 if (TYPE_PRECISION (float_type_node) * 2
3031 == TYPE_PRECISION (long_integer_type_node))
3033 g77_longint_type_node = long_integer_type_node;
3034 g77_ulongint_type_node = long_unsigned_type_node;
3036 else if (TYPE_PRECISION (float_type_node) * 2
3037 == TYPE_PRECISION (long_long_integer_type_node))
3039 g77_longint_type_node = long_long_integer_type_node;
3040 g77_ulongint_type_node = long_long_unsigned_type_node;
3042 else
3043 g77_longint_type_node = g77_ulongint_type_node = NULL_TREE;
3045 if (g77_longint_type_node != NULL_TREE)
3047 pushdecl (build_decl (TYPE_DECL, get_identifier ("__g77_longint"),
3048 g77_longint_type_node));
3049 pushdecl (build_decl (TYPE_DECL, get_identifier ("__g77_ulongint"),
3050 g77_ulongint_type_node));
3053 pedantic_lvalues = pedantic;
3055 make_fname_decl = c_make_fname_decl;
3056 start_fname_decls ();
3058 /* Prepare to check format strings against argument lists. */
3059 init_function_format_info ();
3061 incomplete_decl_finalize_hook = finish_incomplete_decl;
3063 /* Record our roots. */
3065 ggc_add_tree_root (c_global_trees, CTI_MAX);
3066 ggc_add_root (&c_stmt_tree, 1, sizeof c_stmt_tree, mark_stmt_tree);
3067 ggc_add_tree_root (&c_scope_stmt_stack, 1);
3068 ggc_add_tree_root (&named_labels, 1);
3069 ggc_add_tree_root (&shadowed_labels, 1);
3070 ggc_add_root (&current_binding_level, 1, sizeof current_binding_level,
3071 mark_binding_level);
3072 ggc_add_root (&label_level_chain, 1, sizeof label_level_chain,
3073 mark_binding_level);
3074 ggc_add_tree_root (&static_ctors, 1);
3075 ggc_add_tree_root (&static_dtors, 1);
3078 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
3079 decl, NAME is the initialization string and TYPE_DEP indicates whether
3080 NAME depended on the type of the function. As we don't yet implement
3081 delayed emission of static data, we mark the decl as emitted
3082 so it is not placed in the output. Anything using it must therefore pull
3083 out the STRING_CST initializer directly. This does mean that these names
3084 are string merging candidates, which is wrong for C99's __func__. FIXME. */
3086 static tree
3087 c_make_fname_decl (id, type_dep)
3088 tree id;
3089 int type_dep;
3091 const char *name = fname_as_string (type_dep);
3092 tree decl, type, init;
3093 size_t length = strlen (name);
3095 type = build_array_type
3096 (build_qualified_type (char_type_node, TYPE_QUAL_CONST),
3097 build_index_type (size_int (length)));
3099 decl = build_decl (VAR_DECL, id, type);
3100 /* We don't push the decl, so have to set its context here. */
3101 DECL_CONTEXT (decl) = current_function_decl;
3103 TREE_STATIC (decl) = 1;
3104 TREE_READONLY (decl) = 1;
3105 DECL_ARTIFICIAL (decl) = 1;
3107 init = build_string (length + 1, name);
3108 TREE_TYPE (init) = type;
3109 DECL_INITIAL (decl) = init;
3111 TREE_USED (decl) = 1;
3113 finish_decl (decl, init, NULL_TREE);
3115 return decl;
3118 /* Return a definition for a builtin function named NAME and whose data type
3119 is TYPE. TYPE should be a function type with argument types.
3120 FUNCTION_CODE tells later passes how to compile calls to this function.
3121 See tree.h for its possible values.
3123 If LIBRARY_NAME is nonzero, use that for DECL_ASSEMBLER_NAME,
3124 the name to be called if we can't opencode the function. */
3126 tree
3127 builtin_function (name, type, function_code, class, library_name)
3128 const char *name;
3129 tree type;
3130 int function_code;
3131 enum built_in_class class;
3132 const char *library_name;
3134 tree decl = build_decl (FUNCTION_DECL, get_identifier (name), type);
3135 DECL_EXTERNAL (decl) = 1;
3136 TREE_PUBLIC (decl) = 1;
3137 /* If -traditional, permit redefining a builtin function any way you like.
3138 (Though really, if the program redefines these functions,
3139 it probably won't work right unless compiled with -fno-builtin.) */
3140 if (flag_traditional && name[0] != '_')
3141 DECL_BUILT_IN_NONANSI (decl) = 1;
3142 if (library_name)
3143 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (library_name));
3144 make_decl_rtl (decl, NULL);
3145 pushdecl (decl);
3146 DECL_BUILT_IN_CLASS (decl) = class;
3147 DECL_FUNCTION_CODE (decl) = function_code;
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;
3154 return decl;
3157 /* Called when a declaration is seen that contains no names to declare.
3158 If its type is a reference to a structure, union or enum inherited
3159 from a containing scope, shadow that tag name for the current scope
3160 with a forward reference.
3161 If its type defines a new named structure or union
3162 or defines an enum, it is valid but we need not do anything here.
3163 Otherwise, it is an error. */
3165 void
3166 shadow_tag (declspecs)
3167 tree declspecs;
3169 shadow_tag_warned (declspecs, 0);
3172 void
3173 shadow_tag_warned (declspecs, warned)
3174 tree declspecs;
3175 int warned;
3176 /* 1 => we have done a pedwarn. 2 => we have done a warning, but
3177 no pedwarn. */
3179 int found_tag = 0;
3180 register tree link;
3181 tree specs, attrs;
3183 pending_invalid_xref = 0;
3185 /* Remove the attributes from declspecs, since they will confuse the
3186 following code. */
3187 split_specs_attrs (declspecs, &specs, &attrs);
3189 for (link = specs; link; link = TREE_CHAIN (link))
3191 register tree value = TREE_VALUE (link);
3192 register enum tree_code code = TREE_CODE (value);
3194 if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
3195 /* Used to test also that TYPE_SIZE (value) != 0.
3196 That caused warning for `struct foo;' at top level in the file. */
3198 register tree name = lookup_tag_reverse (value);
3199 register tree t;
3201 found_tag++;
3203 if (name == 0)
3205 if (warned != 1 && code != ENUMERAL_TYPE)
3206 /* Empty unnamed enum OK */
3208 pedwarn ("unnamed struct/union that defines no instances");
3209 warned = 1;
3212 else
3214 t = lookup_tag (code, name, current_binding_level, 1);
3216 if (t == 0)
3218 t = make_node (code);
3219 pushtag (name, t);
3223 else
3225 if (!warned && ! in_system_header)
3227 warning ("useless keyword or type name in empty declaration");
3228 warned = 2;
3233 if (found_tag > 1)
3234 error ("two types specified in one empty declaration");
3236 if (warned != 1)
3238 if (found_tag == 0)
3239 pedwarn ("empty declaration");
3243 /* Construct an array declarator. EXPR is the expression inside [], or
3244 NULL_TREE. QUALS are the type qualifiers inside the [] (to be applied
3245 to the pointer to which a parameter array is converted). STATIC_P is
3246 non-zero if "static" is inside the [], zero otherwise. VLA_UNSPEC_P
3247 is non-zero is the array is [*], a VLA of unspecified length which is
3248 nevertheless a complete type (not currently implemented by GCC),
3249 zero otherwise. The declarator is constructed as an ARRAY_REF
3250 (to be decoded by grokdeclarator), whose operand 0 is what's on the
3251 left of the [] (filled by in set_array_declarator_type) and operand 1
3252 is the expression inside; whose TREE_TYPE is the type qualifiers and
3253 which has TREE_STATIC set if "static" is used. */
3255 tree
3256 build_array_declarator (expr, quals, static_p, vla_unspec_p)
3257 tree expr;
3258 tree quals;
3259 int static_p;
3260 int vla_unspec_p;
3262 tree decl;
3263 decl = build_nt (ARRAY_REF, NULL_TREE, expr);
3264 TREE_TYPE (decl) = quals;
3265 TREE_STATIC (decl) = (static_p ? 1 : 0);
3266 if (pedantic && !flag_isoc99)
3268 if (static_p || quals != NULL_TREE)
3269 pedwarn ("ISO C89 does not support `static' or type qualifiers in parameter array declarators");
3270 if (vla_unspec_p)
3271 pedwarn ("ISO C89 does not support `[*]' array declarators");
3273 if (vla_unspec_p)
3274 warning ("GCC does not yet properly implement `[*]' array declarators");
3275 return decl;
3278 /* Set the type of an array declarator. DECL is the declarator, as
3279 constructed by build_array_declarator; TYPE is what appears on the left
3280 of the [] and goes in operand 0. ABSTRACT_P is non-zero if it is an
3281 abstract declarator, zero otherwise; this is used to reject static and
3282 type qualifiers in abstract declarators, where they are not in the
3283 C99 grammar. */
3285 tree
3286 set_array_declarator_type (decl, type, abstract_p)
3287 tree decl;
3288 tree type;
3289 int abstract_p;
3291 TREE_OPERAND (decl, 0) = type;
3292 if (abstract_p && (TREE_TYPE (decl) != NULL_TREE || TREE_STATIC (decl)))
3293 error ("static or type qualifiers in abstract declarator");
3294 return decl;
3297 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
3299 tree
3300 groktypename (typename)
3301 tree typename;
3303 if (TREE_CODE (typename) != TREE_LIST)
3304 return typename;
3305 return grokdeclarator (TREE_VALUE (typename),
3306 TREE_PURPOSE (typename),
3307 TYPENAME, 0);
3310 /* Return a PARM_DECL node for a given pair of specs and declarator. */
3312 tree
3313 groktypename_in_parm_context (typename)
3314 tree typename;
3316 if (TREE_CODE (typename) != TREE_LIST)
3317 return typename;
3318 return grokdeclarator (TREE_VALUE (typename),
3319 TREE_PURPOSE (typename),
3320 PARM, 0);
3323 /* Decode a declarator in an ordinary declaration or data definition.
3324 This is called as soon as the type information and variable name
3325 have been parsed, before parsing the initializer if any.
3326 Here we create the ..._DECL node, fill in its type,
3327 and put it on the list of decls for the current context.
3328 The ..._DECL node is returned as the value.
3330 Exception: for arrays where the length is not specified,
3331 the type is left null, to be filled in by `finish_decl'.
3333 Function definitions do not come here; they go to start_function
3334 instead. However, external and forward declarations of functions
3335 do go through here. Structure field declarations are done by
3336 grokfield and not through here. */
3338 tree
3339 start_decl (declarator, declspecs, initialized, attributes)
3340 tree declarator, declspecs;
3341 int initialized;
3342 tree attributes;
3344 register tree decl = grokdeclarator (declarator, declspecs,
3345 NORMAL, initialized);
3346 register tree tem;
3348 if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
3349 && MAIN_NAME_P (DECL_NAME (decl)))
3350 warning_with_decl (decl, "`%s' is usually a function");
3352 if (initialized)
3353 /* Is it valid for this decl to have an initializer at all?
3354 If not, set INITIALIZED to zero, which will indirectly
3355 tell `finish_decl' to ignore the initializer once it is parsed. */
3356 switch (TREE_CODE (decl))
3358 case TYPE_DECL:
3359 /* typedef foo = bar means give foo the same type as bar.
3360 We haven't parsed bar yet, so `finish_decl' will fix that up.
3361 Any other case of an initialization in a TYPE_DECL is an error. */
3362 if (pedantic || list_length (declspecs) > 1)
3364 error ("typedef `%s' is initialized",
3365 IDENTIFIER_POINTER (DECL_NAME (decl)));
3366 initialized = 0;
3368 break;
3370 case FUNCTION_DECL:
3371 error ("function `%s' is initialized like a variable",
3372 IDENTIFIER_POINTER (DECL_NAME (decl)));
3373 initialized = 0;
3374 break;
3376 case PARM_DECL:
3377 /* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE. */
3378 error ("parameter `%s' is initialized",
3379 IDENTIFIER_POINTER (DECL_NAME (decl)));
3380 initialized = 0;
3381 break;
3383 default:
3384 /* Don't allow initializations for incomplete types
3385 except for arrays which might be completed by the initialization. */
3387 /* This can happen if the array size is an undefined macro. We already
3388 gave a warning, so we don't need another one. */
3389 if (TREE_TYPE (decl) == error_mark_node)
3390 initialized = 0;
3391 else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
3393 /* A complete type is ok if size is fixed. */
3395 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
3396 || C_DECL_VARIABLE_SIZE (decl))
3398 error ("variable-sized object may not be initialized");
3399 initialized = 0;
3402 else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
3404 error ("variable `%s' has initializer but incomplete type",
3405 IDENTIFIER_POINTER (DECL_NAME (decl)));
3406 initialized = 0;
3408 else if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
3410 error ("elements of array `%s' have incomplete type",
3411 IDENTIFIER_POINTER (DECL_NAME (decl)));
3412 initialized = 0;
3416 if (initialized)
3418 #if 0
3419 /* Seems redundant with grokdeclarator. */
3420 if (current_binding_level != global_binding_level
3421 && DECL_EXTERNAL (decl)
3422 && TREE_CODE (decl) != FUNCTION_DECL)
3423 warning ("declaration of `%s' has `extern' and is initialized",
3424 IDENTIFIER_POINTER (DECL_NAME (decl)));
3425 #endif
3426 DECL_EXTERNAL (decl) = 0;
3427 if (current_binding_level == global_binding_level)
3428 TREE_STATIC (decl) = 1;
3430 /* Tell `pushdecl' this is an initialized decl
3431 even though we don't yet have the initializer expression.
3432 Also tell `finish_decl' it may store the real initializer. */
3433 DECL_INITIAL (decl) = error_mark_node;
3436 /* If this is a function declaration, write a record describing it to the
3437 prototypes file (if requested). */
3439 if (TREE_CODE (decl) == FUNCTION_DECL)
3440 gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);
3442 /* ANSI specifies that a tentative definition which is not merged with
3443 a non-tentative definition behaves exactly like a definition with an
3444 initializer equal to zero. (Section 3.7.2)
3445 -fno-common gives strict ANSI behavior. Usually you don't want it.
3446 This matters only for variables with external linkage. */
3447 if (! flag_no_common || ! TREE_PUBLIC (decl))
3448 DECL_COMMON (decl) = 1;
3450 /* Set attributes here so if duplicate decl, will have proper attributes. */
3451 decl_attributes (decl, attributes);
3453 /* Add this decl to the current binding level.
3454 TEM may equal DECL or it may be a previous decl of the same name. */
3455 tem = pushdecl (decl);
3457 /* For a local variable, define the RTL now. */
3458 if (current_binding_level != global_binding_level
3459 /* But not if this is a duplicate decl
3460 and we preserved the rtl from the previous one
3461 (which may or may not happen). */
3462 && !DECL_RTL_SET_P (tem)
3463 && !DECL_CONTEXT (tem))
3465 if (TREE_TYPE (tem) != error_mark_node
3466 && COMPLETE_TYPE_P (TREE_TYPE (tem)))
3467 expand_decl (tem);
3468 else if (TREE_CODE (TREE_TYPE (tem)) == ARRAY_TYPE
3469 && DECL_INITIAL (tem) != 0)
3470 expand_decl (tem);
3473 return tem;
3476 /* Finish processing of a declaration;
3477 install its initial value.
3478 If the length of an array type is not known before,
3479 it must be determined now, from the initial value, or it is an error. */
3481 void
3482 finish_decl (decl, init, asmspec_tree)
3483 tree decl, init;
3484 tree asmspec_tree;
3486 register tree type = TREE_TYPE (decl);
3487 int was_incomplete = (DECL_SIZE (decl) == 0);
3488 const char *asmspec = 0;
3490 /* If a name was specified, get the string. */
3491 if (asmspec_tree)
3492 asmspec = TREE_STRING_POINTER (asmspec_tree);
3494 /* If `start_decl' didn't like having an initialization, ignore it now. */
3495 if (init != 0 && DECL_INITIAL (decl) == 0)
3496 init = 0;
3498 /* Don't crash if parm is initialized. */
3499 if (TREE_CODE (decl) == PARM_DECL)
3500 init = 0;
3502 if (init)
3504 if (TREE_CODE (decl) != TYPE_DECL)
3505 store_init_value (decl, init);
3506 else
3508 /* typedef foo = bar; store the type of bar as the type of foo. */
3509 TREE_TYPE (decl) = TREE_TYPE (init);
3510 DECL_INITIAL (decl) = init = 0;
3514 /* Deduce size of array from initialization, if not already known */
3515 if (TREE_CODE (type) == ARRAY_TYPE
3516 && TYPE_DOMAIN (type) == 0
3517 && TREE_CODE (decl) != TYPE_DECL)
3519 int do_default
3520 = (TREE_STATIC (decl)
3521 /* Even if pedantic, an external linkage array
3522 may have incomplete type at first. */
3523 ? pedantic && !TREE_PUBLIC (decl)
3524 : !DECL_EXTERNAL (decl));
3525 int failure
3526 = complete_array_type (type, DECL_INITIAL (decl), do_default);
3528 /* Get the completed type made by complete_array_type. */
3529 type = TREE_TYPE (decl);
3531 if (failure == 1)
3532 error_with_decl (decl, "initializer fails to determine size of `%s'");
3534 else if (failure == 2)
3536 if (do_default)
3537 error_with_decl (decl, "array size missing in `%s'");
3538 /* If a `static' var's size isn't known,
3539 make it extern as well as static, so it does not get
3540 allocated.
3541 If it is not `static', then do not mark extern;
3542 finish_incomplete_decl will give it a default size
3543 and it will get allocated. */
3544 else if (!pedantic && TREE_STATIC (decl) && ! TREE_PUBLIC (decl))
3545 DECL_EXTERNAL (decl) = 1;
3548 /* TYPE_MAX_VALUE is always one less than the number of elements
3549 in the array, because we start counting at zero. Therefore,
3550 warn only if the value is less than zero. */
3551 else if (pedantic && TYPE_DOMAIN (type) != 0
3552 && tree_int_cst_sgn (TYPE_MAX_VALUE (TYPE_DOMAIN (type))) < 0)
3553 error_with_decl (decl, "zero or negative size array `%s'");
3555 layout_decl (decl, 0);
3558 if (TREE_CODE (decl) == VAR_DECL)
3560 if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
3561 && COMPLETE_TYPE_P (TREE_TYPE (decl)))
3562 layout_decl (decl, 0);
3564 if (DECL_SIZE (decl) == 0
3565 /* Don't give an error if we already gave one earlier. */
3566 && TREE_TYPE (decl) != error_mark_node
3567 && (TREE_STATIC (decl)
3569 /* A static variable with an incomplete type
3570 is an error if it is initialized.
3571 Also if it is not file scope.
3572 Otherwise, let it through, but if it is not `extern'
3573 then it may cause an error message later. */
3574 (DECL_INITIAL (decl) != 0
3575 || DECL_CONTEXT (decl) != 0)
3577 /* An automatic variable with an incomplete type
3578 is an error. */
3579 !DECL_EXTERNAL (decl)))
3581 error_with_decl (decl, "storage size of `%s' isn't known");
3582 TREE_TYPE (decl) = error_mark_node;
3585 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
3586 && DECL_SIZE (decl) != 0)
3588 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
3589 constant_expression_warning (DECL_SIZE (decl));
3590 else
3591 error_with_decl (decl, "storage size of `%s' isn't constant");
3594 if (TREE_USED (type))
3595 TREE_USED (decl) = 1;
3598 /* If this is a function and an assembler name is specified, it isn't
3599 builtin any more. Also reset DECL_RTL so we can give it its new
3600 name. */
3601 if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
3603 DECL_BUILT_IN_CLASS (decl) = NOT_BUILT_IN;
3604 SET_DECL_RTL (decl, NULL_RTX);
3605 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (asmspec));
3608 /* Output the assembler code and/or RTL code for variables and functions,
3609 unless the type is an undefined structure or union.
3610 If not, it will get done when the type is completed. */
3612 if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
3614 /* This is a no-op in c-lang.c or something real in objc-actions.c. */
3615 maybe_objc_check_decl (decl);
3617 if (!DECL_CONTEXT (decl))
3619 if (DECL_INITIAL (decl) == NULL_TREE
3620 || DECL_INITIAL (decl) == error_mark_node)
3621 /* Don't output anything
3622 when a tentative file-scope definition is seen.
3623 But at end of compilation, do output code for them. */
3624 DECL_DEFER_OUTPUT (decl) = 1;
3625 rest_of_decl_compilation (decl, asmspec,
3626 (DECL_CONTEXT (decl) == 0
3627 || TREE_ASM_WRITTEN (decl)), 0);
3629 else
3631 /* This is a local variable. If there is an ASMSPEC, the
3632 user has requested that we handle it specially. */
3633 if (asmspec)
3635 /* In conjunction with an ASMSPEC, the `register'
3636 keyword indicates that we should place the variable
3637 in a particular register. */
3638 if (DECL_REGISTER (decl))
3639 DECL_C_HARD_REGISTER (decl) = 1;
3641 /* If this is not a static variable, issue a warning.
3642 It doesn't make any sense to give an ASMSPEC for an
3643 ordinary, non-register local variable. Historically,
3644 GCC has accepted -- but ignored -- the ASMSPEC in
3645 this case. */
3646 if (TREE_CODE (decl) == VAR_DECL
3647 && !DECL_REGISTER (decl)
3648 && !TREE_STATIC (decl))
3649 warning_with_decl (decl,
3650 "ignoring asm-specifier for non-static local variable `%s'");
3651 else
3652 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (asmspec));
3655 add_decl_stmt (decl);
3658 if (DECL_CONTEXT (decl) != 0)
3660 /* Recompute the RTL of a local array now
3661 if it used to be an incomplete type. */
3662 if (was_incomplete
3663 && ! TREE_STATIC (decl) && ! DECL_EXTERNAL (decl))
3665 /* If we used it already as memory, it must stay in memory. */
3666 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
3667 /* If it's still incomplete now, no init will save it. */
3668 if (DECL_SIZE (decl) == 0)
3669 DECL_INITIAL (decl) = 0;
3674 if (TREE_CODE (decl) == TYPE_DECL)
3676 /* This is a no-op in c-lang.c or something real in objc-actions.c. */
3677 maybe_objc_check_decl (decl);
3678 rest_of_decl_compilation (decl, NULL, DECL_CONTEXT (decl) == 0, 0);
3681 /* At the end of a declaration, throw away any variable type sizes
3682 of types defined inside that declaration. There is no use
3683 computing them in the following function definition. */
3684 if (current_binding_level == global_binding_level)
3685 get_pending_sizes ();
3688 /* If DECL has a cleanup, build and return that cleanup here.
3689 This is a callback called by expand_expr. */
3691 tree
3692 maybe_build_cleanup (decl)
3693 tree decl ATTRIBUTE_UNUSED;
3695 /* There are no cleanups in C. */
3696 return NULL_TREE;
3699 /* Given a parsed parameter declaration,
3700 decode it into a PARM_DECL and push that on the current binding level.
3701 Also, for the sake of forward parm decls,
3702 record the given order of parms in `parm_order'. */
3704 void
3705 push_parm_decl (parm)
3706 tree parm;
3708 tree decl;
3709 int old_immediate_size_expand = immediate_size_expand;
3710 /* Don't try computing parm sizes now -- wait till fn is called. */
3711 immediate_size_expand = 0;
3713 decl = grokdeclarator (TREE_VALUE (TREE_PURPOSE (parm)),
3714 TREE_PURPOSE (TREE_PURPOSE (parm)), PARM, 0);
3715 decl_attributes (decl, TREE_VALUE (parm));
3717 #if 0
3718 if (DECL_NAME (decl))
3720 tree olddecl;
3721 olddecl = lookup_name (DECL_NAME (decl));
3722 if (pedantic && olddecl != 0 && TREE_CODE (olddecl) == TYPE_DECL)
3723 pedwarn_with_decl (decl,
3724 "ANSI C forbids parameter `%s' shadowing typedef");
3726 #endif
3728 decl = pushdecl (decl);
3730 immediate_size_expand = old_immediate_size_expand;
3732 current_binding_level->parm_order
3733 = tree_cons (NULL_TREE, decl, current_binding_level->parm_order);
3735 /* Add this decl to the current binding level. */
3736 finish_decl (decl, NULL_TREE, NULL_TREE);
3739 /* Clear the given order of parms in `parm_order'.
3740 Used at start of parm list,
3741 and also at semicolon terminating forward decls. */
3743 void
3744 clear_parm_order ()
3746 current_binding_level->parm_order = NULL_TREE;
3749 /* Make TYPE a complete type based on INITIAL_VALUE.
3750 Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
3751 2 if there was no information (in which case assume 1 if DO_DEFAULT). */
3754 complete_array_type (type, initial_value, do_default)
3755 tree type;
3756 tree initial_value;
3757 int do_default;
3759 register tree maxindex = NULL_TREE;
3760 int value = 0;
3762 if (initial_value)
3764 /* Note MAXINDEX is really the maximum index,
3765 one less than the size. */
3766 if (TREE_CODE (initial_value) == STRING_CST)
3768 int eltsize
3769 = int_size_in_bytes (TREE_TYPE (TREE_TYPE (initial_value)));
3770 maxindex = build_int_2 ((TREE_STRING_LENGTH (initial_value)
3771 / eltsize) - 1, 0);
3773 else if (TREE_CODE (initial_value) == CONSTRUCTOR)
3775 tree elts = CONSTRUCTOR_ELTS (initial_value);
3776 maxindex = build_int_2 (-1, -1);
3777 for (; elts; elts = TREE_CHAIN (elts))
3779 if (TREE_PURPOSE (elts))
3780 maxindex = TREE_PURPOSE (elts);
3781 else
3782 maxindex = fold (build (PLUS_EXPR, integer_type_node,
3783 maxindex, integer_one_node));
3785 maxindex = copy_node (maxindex);
3787 else
3789 /* Make an error message unless that happened already. */
3790 if (initial_value != error_mark_node)
3791 value = 1;
3793 /* Prevent further error messages. */
3794 maxindex = build_int_2 (0, 0);
3798 if (!maxindex)
3800 if (do_default)
3801 maxindex = build_int_2 (0, 0);
3802 value = 2;
3805 if (maxindex)
3807 TYPE_DOMAIN (type) = build_index_type (maxindex);
3808 if (!TREE_TYPE (maxindex))
3809 TREE_TYPE (maxindex) = TYPE_DOMAIN (type);
3812 /* Lay out the type now that we can get the real answer. */
3814 layout_type (type);
3816 return value;
3819 /* Given declspecs and a declarator,
3820 determine the name and type of the object declared
3821 and construct a ..._DECL node for it.
3822 (In one case we can return a ..._TYPE node instead.
3823 For invalid input we sometimes return 0.)
3825 DECLSPECS is a chain of tree_list nodes whose value fields
3826 are the storage classes and type specifiers.
3828 DECL_CONTEXT says which syntactic context this declaration is in:
3829 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
3830 FUNCDEF for a function definition. Like NORMAL but a few different
3831 error messages in each case. Return value may be zero meaning
3832 this definition is too screwy to try to parse.
3833 PARM for a parameter declaration (either within a function prototype
3834 or before a function body). Make a PARM_DECL, or return void_type_node.
3835 TYPENAME if for a typename (in a cast or sizeof).
3836 Don't make a DECL node; just return the ..._TYPE node.
3837 FIELD for a struct or union field; make a FIELD_DECL.
3838 BITFIELD for a field with specified width.
3839 INITIALIZED is 1 if the decl has an initializer.
3841 In the TYPENAME case, DECLARATOR is really an absolute declarator.
3842 It may also be so in the PARM case, for a prototype where the
3843 argument type is specified but not the name.
3845 This function is where the complicated C meanings of `static'
3846 and `extern' are interpreted. */
3848 static tree
3849 grokdeclarator (declarator, declspecs, decl_context, initialized)
3850 tree declspecs;
3851 tree declarator;
3852 enum decl_context decl_context;
3853 int initialized;
3855 int specbits = 0;
3856 tree spec;
3857 tree type = NULL_TREE;
3858 int longlong = 0;
3859 int constp;
3860 int restrictp;
3861 int volatilep;
3862 int type_quals = TYPE_UNQUALIFIED;
3863 int inlinep;
3864 int explicit_int = 0;
3865 int explicit_char = 0;
3866 int defaulted_int = 0;
3867 tree typedef_decl = 0;
3868 const char *name;
3869 tree typedef_type = 0;
3870 int funcdef_flag = 0;
3871 enum tree_code innermost_code = ERROR_MARK;
3872 int bitfield = 0;
3873 int size_varies = 0;
3874 tree decl_machine_attr = NULL_TREE;
3875 tree array_ptr_quals = NULL_TREE;
3876 int array_parm_static = 0;
3878 if (decl_context == BITFIELD)
3879 bitfield = 1, decl_context = FIELD;
3881 if (decl_context == FUNCDEF)
3882 funcdef_flag = 1, decl_context = NORMAL;
3884 /* Look inside a declarator for the name being declared
3885 and get it as a string, for an error message. */
3887 register tree decl = declarator;
3888 name = 0;
3890 while (decl)
3891 switch (TREE_CODE (decl))
3893 case ARRAY_REF:
3894 case INDIRECT_REF:
3895 case CALL_EXPR:
3896 innermost_code = TREE_CODE (decl);
3897 decl = TREE_OPERAND (decl, 0);
3898 break;
3900 case IDENTIFIER_NODE:
3901 name = IDENTIFIER_POINTER (decl);
3902 decl = 0;
3903 break;
3905 default:
3906 abort ();
3908 if (name == 0)
3909 name = "type name";
3912 /* A function definition's declarator must have the form of
3913 a function declarator. */
3915 if (funcdef_flag && innermost_code != CALL_EXPR)
3916 return 0;
3918 /* Anything declared one level down from the top level
3919 must be one of the parameters of a function
3920 (because the body is at least two levels down). */
3922 /* If this looks like a function definition, make it one,
3923 even if it occurs where parms are expected.
3924 Then store_parm_decls will reject it and not use it as a parm. */
3925 if (decl_context == NORMAL && !funcdef_flag
3926 && current_binding_level->parm_flag)
3927 decl_context = PARM;
3929 /* Look through the decl specs and record which ones appear.
3930 Some typespecs are defined as built-in typenames.
3931 Others, the ones that are modifiers of other types,
3932 are represented by bits in SPECBITS: set the bits for
3933 the modifiers that appear. Storage class keywords are also in SPECBITS.
3935 If there is a typedef name or a type, store the type in TYPE.
3936 This includes builtin typedefs such as `int'.
3938 Set EXPLICIT_INT or EXPLICIT_CHAR if the type is `int' or `char'
3939 and did not come from a user typedef.
3941 Set LONGLONG if `long' is mentioned twice. */
3943 for (spec = declspecs; spec; spec = TREE_CHAIN (spec))
3945 register tree id = TREE_VALUE (spec);
3947 if (id == ridpointers[(int) RID_INT])
3948 explicit_int = 1;
3949 if (id == ridpointers[(int) RID_CHAR])
3950 explicit_char = 1;
3952 if (TREE_CODE (id) == IDENTIFIER_NODE && C_IS_RESERVED_WORD (id))
3954 enum rid i = C_RID_CODE (id);
3955 if ((int) i <= (int) RID_LAST_MODIFIER)
3957 if (i == RID_LONG && (specbits & (1 << (int) i)))
3959 if (longlong)
3960 error ("`long long long' is too long for GCC");
3961 else
3963 if (pedantic && !flag_isoc99 && ! in_system_header
3964 && warn_long_long)
3965 pedwarn ("ISO C89 does not support `long long'");
3966 longlong = 1;
3969 else if (specbits & (1 << (int) i))
3970 pedwarn ("duplicate `%s'", IDENTIFIER_POINTER (id));
3971 specbits |= 1 << (int) i;
3972 goto found;
3975 if (type)
3976 error ("two or more data types in declaration of `%s'", name);
3977 /* Actual typedefs come to us as TYPE_DECL nodes. */
3978 else if (TREE_CODE (id) == TYPE_DECL)
3980 type = TREE_TYPE (id);
3981 decl_machine_attr = DECL_MACHINE_ATTRIBUTES (id);
3982 typedef_decl = id;
3984 /* Built-in types come as identifiers. */
3985 else if (TREE_CODE (id) == IDENTIFIER_NODE)
3987 register tree t = lookup_name (id);
3988 if (TREE_TYPE (t) == error_mark_node)
3990 else if (!t || TREE_CODE (t) != TYPE_DECL)
3991 error ("`%s' fails to be a typedef or built in type",
3992 IDENTIFIER_POINTER (id));
3993 else
3995 type = TREE_TYPE (t);
3996 typedef_decl = t;
3999 else if (TREE_CODE (id) != ERROR_MARK)
4000 type = id;
4002 found:
4006 typedef_type = type;
4007 if (type)
4008 size_varies = C_TYPE_VARIABLE_SIZE (type);
4010 /* No type at all: default to `int', and set DEFAULTED_INT
4011 because it was not a user-defined typedef. */
4013 if (type == 0)
4015 if ((! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4016 | (1 << (int) RID_SIGNED)
4017 | (1 << (int) RID_UNSIGNED)
4018 | (1 << (int) RID_COMPLEX))))
4019 /* Don't warn about typedef foo = bar. */
4020 && ! (specbits & (1 << (int) RID_TYPEDEF) && initialized)
4021 && ! in_system_header)
4023 /* Issue a warning if this is an ISO C 99 program or if -Wreturn-type
4024 and this is a function, or if -Wimplicit; prefer the former
4025 warning since it is more explicit. */
4026 if ((warn_implicit_int || warn_return_type || flag_isoc99)
4027 && funcdef_flag)
4028 warn_about_return_type = 1;
4029 else if (warn_implicit_int || flag_isoc99)
4030 pedwarn_c99 ("type defaults to `int' in declaration of `%s'",
4031 name);
4034 defaulted_int = 1;
4035 type = integer_type_node;
4038 /* Now process the modifiers that were specified
4039 and check for invalid combinations. */
4041 /* Long double is a special combination. */
4043 if ((specbits & 1 << (int) RID_LONG) && ! longlong
4044 && TYPE_MAIN_VARIANT (type) == double_type_node)
4046 specbits &= ~(1 << (int) RID_LONG);
4047 type = long_double_type_node;
4050 /* Check all other uses of type modifiers. */
4052 if (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4053 | (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED)))
4055 int ok = 0;
4057 if ((specbits & 1 << (int) RID_LONG)
4058 && (specbits & 1 << (int) RID_SHORT))
4059 error ("both long and short specified for `%s'", name);
4060 else if (((specbits & 1 << (int) RID_LONG)
4061 || (specbits & 1 << (int) RID_SHORT))
4062 && explicit_char)
4063 error ("long or short specified with char for `%s'", name);
4064 else if (((specbits & 1 << (int) RID_LONG)
4065 || (specbits & 1 << (int) RID_SHORT))
4066 && TREE_CODE (type) == REAL_TYPE)
4068 static int already = 0;
4070 error ("long or short specified with floating type for `%s'", name);
4071 if (! already && ! pedantic)
4073 error ("the only valid combination is `long double'");
4074 already = 1;
4077 else if ((specbits & 1 << (int) RID_SIGNED)
4078 && (specbits & 1 << (int) RID_UNSIGNED))
4079 error ("both signed and unsigned specified for `%s'", name);
4080 else if (TREE_CODE (type) != INTEGER_TYPE)
4081 error ("long, short, signed or unsigned invalid for `%s'", name);
4082 else
4084 ok = 1;
4085 if (!explicit_int && !defaulted_int && !explicit_char && pedantic)
4087 pedwarn ("long, short, signed or unsigned used invalidly for `%s'",
4088 name);
4089 if (flag_pedantic_errors)
4090 ok = 0;
4094 /* Discard the type modifiers if they are invalid. */
4095 if (! ok)
4097 specbits &= ~((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4098 | (1 << (int) RID_UNSIGNED) | (1 << (int) RID_SIGNED));
4099 longlong = 0;
4103 if ((specbits & (1 << (int) RID_COMPLEX))
4104 && TREE_CODE (type) != INTEGER_TYPE && TREE_CODE (type) != REAL_TYPE)
4106 error ("complex invalid for `%s'", name);
4107 specbits &= ~(1 << (int) RID_COMPLEX);
4110 /* Decide whether an integer type is signed or not.
4111 Optionally treat bitfields as signed by default. */
4112 if (specbits & 1 << (int) RID_UNSIGNED
4113 /* Traditionally, all bitfields are unsigned. */
4114 || (bitfield && flag_traditional
4115 && (! explicit_flag_signed_bitfields || !flag_signed_bitfields))
4116 || (bitfield && ! flag_signed_bitfields
4117 && (explicit_int || defaulted_int || explicit_char
4118 /* A typedef for plain `int' without `signed'
4119 can be controlled just like plain `int'. */
4120 || ! (typedef_decl != 0
4121 && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
4122 && TREE_CODE (type) != ENUMERAL_TYPE
4123 && !(specbits & 1 << (int) RID_SIGNED)))
4125 if (longlong)
4126 type = long_long_unsigned_type_node;
4127 else if (specbits & 1 << (int) RID_LONG)
4128 type = long_unsigned_type_node;
4129 else if (specbits & 1 << (int) RID_SHORT)
4130 type = short_unsigned_type_node;
4131 else if (type == char_type_node)
4132 type = unsigned_char_type_node;
4133 else if (typedef_decl)
4134 type = unsigned_type (type);
4135 else
4136 type = unsigned_type_node;
4138 else if ((specbits & 1 << (int) RID_SIGNED)
4139 && type == char_type_node)
4140 type = signed_char_type_node;
4141 else if (longlong)
4142 type = long_long_integer_type_node;
4143 else if (specbits & 1 << (int) RID_LONG)
4144 type = long_integer_type_node;
4145 else if (specbits & 1 << (int) RID_SHORT)
4146 type = short_integer_type_node;
4148 if (specbits & 1 << (int) RID_COMPLEX)
4150 if (pedantic && !flag_isoc99)
4151 pedwarn ("ISO C89 does not support complex types");
4152 /* If we just have "complex", it is equivalent to
4153 "complex double", but if any modifiers at all are specified it is
4154 the complex form of TYPE. E.g, "complex short" is
4155 "complex short int". */
4157 if (defaulted_int && ! longlong
4158 && ! (specbits & ((1 << (int) RID_LONG) | (1 << (int) RID_SHORT)
4159 | (1 << (int) RID_SIGNED)
4160 | (1 << (int) RID_UNSIGNED))))
4162 if (pedantic)
4163 pedwarn ("ISO C does not support plain `complex' meaning `double complex'");
4164 type = complex_double_type_node;
4166 else if (type == integer_type_node)
4168 if (pedantic)
4169 pedwarn ("ISO C does not support complex integer types");
4170 type = complex_integer_type_node;
4172 else if (type == float_type_node)
4173 type = complex_float_type_node;
4174 else if (type == double_type_node)
4175 type = complex_double_type_node;
4176 else if (type == long_double_type_node)
4177 type = complex_long_double_type_node;
4178 else
4180 if (pedantic)
4181 pedwarn ("ISO C does not support complex integer types");
4182 type = build_complex_type (type);
4186 /* Figure out the type qualifiers for the declaration. There are
4187 two ways a declaration can become qualified. One is something
4188 like `const int i' where the `const' is explicit. Another is
4189 something like `typedef const int CI; CI i' where the type of the
4190 declaration contains the `const'. */
4191 constp = !! (specbits & 1 << (int) RID_CONST) + TYPE_READONLY (type);
4192 restrictp = !! (specbits & 1 << (int) RID_RESTRICT) + TYPE_RESTRICT (type);
4193 volatilep = !! (specbits & 1 << (int) RID_VOLATILE) + TYPE_VOLATILE (type);
4194 inlinep = !! (specbits & (1 << (int) RID_INLINE));
4195 if (constp > 1 && ! flag_isoc99)
4196 pedwarn ("duplicate `const'");
4197 if (restrictp > 1 && ! flag_isoc99)
4198 pedwarn ("duplicate `restrict'");
4199 if (volatilep > 1 && ! flag_isoc99)
4200 pedwarn ("duplicate `volatile'");
4201 if (! flag_gen_aux_info && (TYPE_QUALS (type)))
4202 type = TYPE_MAIN_VARIANT (type);
4203 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4204 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4205 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4207 /* Warn if two storage classes are given. Default to `auto'. */
4210 int nclasses = 0;
4212 if (specbits & 1 << (int) RID_AUTO) nclasses++;
4213 if (specbits & 1 << (int) RID_STATIC) nclasses++;
4214 if (specbits & 1 << (int) RID_EXTERN) nclasses++;
4215 if (specbits & 1 << (int) RID_REGISTER) nclasses++;
4216 if (specbits & 1 << (int) RID_TYPEDEF) nclasses++;
4218 /* Warn about storage classes that are invalid for certain
4219 kinds of declarations (parameters, typenames, etc.). */
4221 if (nclasses > 1)
4222 error ("multiple storage classes in declaration of `%s'", name);
4223 else if (funcdef_flag
4224 && (specbits
4225 & ((1 << (int) RID_REGISTER)
4226 | (1 << (int) RID_AUTO)
4227 | (1 << (int) RID_TYPEDEF))))
4229 if (specbits & 1 << (int) RID_AUTO
4230 && (pedantic || current_binding_level == global_binding_level))
4231 pedwarn ("function definition declared `auto'");
4232 if (specbits & 1 << (int) RID_REGISTER)
4233 error ("function definition declared `register'");
4234 if (specbits & 1 << (int) RID_TYPEDEF)
4235 error ("function definition declared `typedef'");
4236 specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
4237 | (1 << (int) RID_AUTO));
4239 else if (decl_context != NORMAL && nclasses > 0)
4241 if (decl_context == PARM && specbits & 1 << (int) RID_REGISTER)
4243 else
4245 switch (decl_context)
4247 case FIELD:
4248 error ("storage class specified for structure field `%s'",
4249 name);
4250 break;
4251 case PARM:
4252 error ("storage class specified for parameter `%s'", name);
4253 break;
4254 default:
4255 error ("storage class specified for typename");
4256 break;
4258 specbits &= ~((1 << (int) RID_TYPEDEF) | (1 << (int) RID_REGISTER)
4259 | (1 << (int) RID_AUTO) | (1 << (int) RID_STATIC)
4260 | (1 << (int) RID_EXTERN));
4263 else if (specbits & 1 << (int) RID_EXTERN && initialized && ! funcdef_flag)
4265 /* `extern' with initialization is invalid if not at top level. */
4266 if (current_binding_level == global_binding_level)
4267 warning ("`%s' initialized and declared `extern'", name);
4268 else
4269 error ("`%s' has both `extern' and initializer", name);
4271 else if (specbits & 1 << (int) RID_EXTERN && funcdef_flag
4272 && current_binding_level != global_binding_level)
4273 error ("nested function `%s' declared `extern'", name);
4274 else if (current_binding_level == global_binding_level
4275 && specbits & (1 << (int) RID_AUTO))
4276 error ("top-level declaration of `%s' specifies `auto'", name);
4279 /* Now figure out the structure of the declarator proper.
4280 Descend through it, creating more complex types, until we reach
4281 the declared identifier (or NULL_TREE, in an absolute declarator). */
4283 while (declarator && TREE_CODE (declarator) != IDENTIFIER_NODE)
4285 if (type == error_mark_node)
4287 declarator = TREE_OPERAND (declarator, 0);
4288 continue;
4291 /* Each level of DECLARATOR is either an ARRAY_REF (for ...[..]),
4292 an INDIRECT_REF (for *...),
4293 a CALL_EXPR (for ...(...)),
4294 an identifier (for the name being declared)
4295 or a null pointer (for the place in an absolute declarator
4296 where the name was omitted).
4297 For the last two cases, we have just exited the loop.
4299 At this point, TYPE is the type of elements of an array,
4300 or for a function to return, or for a pointer to point to.
4301 After this sequence of ifs, TYPE is the type of the
4302 array or function or pointer, and DECLARATOR has had its
4303 outermost layer removed. */
4305 if (array_ptr_quals != NULL_TREE || array_parm_static)
4307 /* Only the innermost declarator (making a parameter be of
4308 array type which is converted to pointer type)
4309 may have static or type qualifiers. */
4310 error ("static or type qualifiers in non-parameter array declarator");
4311 array_ptr_quals = NULL_TREE;
4312 array_parm_static = 0;
4315 if (TREE_CODE (declarator) == ARRAY_REF)
4317 register tree itype = NULL_TREE;
4318 register tree size = TREE_OPERAND (declarator, 1);
4319 /* The index is a signed object `sizetype' bits wide. */
4320 tree index_type = signed_type (sizetype);
4322 array_ptr_quals = TREE_TYPE (declarator);
4323 array_parm_static = TREE_STATIC (declarator);
4325 declarator = TREE_OPERAND (declarator, 0);
4327 /* Check for some types that there cannot be arrays of. */
4329 if (VOID_TYPE_P (type))
4331 error ("declaration of `%s' as array of voids", name);
4332 type = error_mark_node;
4335 if (TREE_CODE (type) == FUNCTION_TYPE)
4337 error ("declaration of `%s' as array of functions", name);
4338 type = error_mark_node;
4341 if (size == error_mark_node)
4342 type = error_mark_node;
4344 if (type == error_mark_node)
4345 continue;
4347 /* If size was specified, set ITYPE to a range-type for that size.
4348 Otherwise, ITYPE remains null. finish_decl may figure it out
4349 from an initial value. */
4351 if (size)
4353 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
4354 STRIP_TYPE_NOPS (size);
4356 if (! INTEGRAL_TYPE_P (TREE_TYPE (size)))
4358 error ("size of array `%s' has non-integer type", name);
4359 size = integer_one_node;
4362 if (pedantic && integer_zerop (size))
4363 pedwarn ("ISO C forbids zero-size array `%s'", name);
4365 if (TREE_CODE (size) == INTEGER_CST)
4367 constant_expression_warning (size);
4368 if (tree_int_cst_sgn (size) < 0)
4370 error ("size of array `%s' is negative", name);
4371 size = integer_one_node;
4374 else
4376 /* Make sure the array size remains visibly nonconstant
4377 even if it is (eg) a const variable with known value. */
4378 size_varies = 1;
4380 if (pedantic)
4382 if (TREE_CONSTANT (size))
4383 pedwarn ("ISO C89 forbids array `%s' whose size can't be evaluated",
4384 name);
4385 else
4386 pedwarn ("ISO C89 forbids variable-size array `%s'",
4387 name);
4391 if (integer_zerop (size))
4393 /* A zero-length array cannot be represented with an
4394 unsigned index type, which is what we'll get with
4395 build_index_type. Create an open-ended range instead. */
4396 itype = build_range_type (sizetype, size, NULL_TREE);
4398 else
4400 /* Compute the maximum valid index, that is, size - 1.
4401 Do the calculation in index_type, so that if it is
4402 a variable the computations will be done in the
4403 proper mode. */
4404 itype = fold (build (MINUS_EXPR, index_type,
4405 convert (index_type, size),
4406 convert (index_type, size_one_node)));
4408 /* If that overflowed, the array is too big.
4409 ??? While a size of INT_MAX+1 technically shouldn't
4410 cause an overflow (because we subtract 1), the overflow
4411 is recorded during the conversion to index_type, before
4412 the subtraction. Handling this case seems like an
4413 unnecessary complication. */
4414 if (TREE_OVERFLOW (itype))
4416 error ("size of array `%s' is too large", name);
4417 type = error_mark_node;
4418 continue;
4421 if (size_varies)
4422 itype = variable_size (itype);
4423 itype = build_index_type (itype);
4426 else if (decl_context == FIELD)
4428 /* ??? Need to check somewhere that this is a structure
4429 and not a union, that this field is last, and that
4430 this structure has at least one other named member. */
4432 if (pedantic && !flag_isoc99 && !in_system_header)
4433 pedwarn ("ISO C89 does not support flexible array members");
4435 /* ISO C99 Flexible array members are effectively identical
4436 to GCC's zero-length array extension. */
4437 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4440 /* If pedantic, complain about arrays of incomplete types. */
4442 if (pedantic && !COMPLETE_TYPE_P (type))
4443 pedwarn ("array type has incomplete element type");
4445 #if 0
4446 /* We shouldn't have a function type here at all!
4447 Functions aren't allowed as array elements. */
4448 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4449 && (constp || volatilep))
4450 pedwarn ("ANSI C forbids const or volatile function types");
4451 #endif
4453 /* Build the array type itself, then merge any constancy or
4454 volatility into the target type. We must do it in this order
4455 to ensure that the TYPE_MAIN_VARIANT field of the array type
4456 is set correctly. */
4458 type = build_array_type (type, itype);
4459 if (type_quals)
4460 type = c_build_qualified_type (type, type_quals);
4462 if (size_varies)
4463 C_TYPE_VARIABLE_SIZE (type) = 1;
4465 /* The GCC extension for zero-length arrays differs from
4466 ISO flexible array members in that sizeof yields zero. */
4467 if (size && integer_zerop (size))
4469 layout_type (type);
4470 TYPE_SIZE (type) = bitsize_zero_node;
4471 TYPE_SIZE_UNIT (type) = size_zero_node;
4473 if (decl_context != PARM
4474 && (array_ptr_quals != NULL_TREE || array_parm_static))
4476 error ("static or type qualifiers in non-parameter array declarator");
4477 array_ptr_quals = NULL_TREE;
4478 array_parm_static = 0;
4481 else if (TREE_CODE (declarator) == CALL_EXPR)
4483 tree arg_types;
4485 /* Declaring a function type.
4486 Make sure we have a valid type for the function to return. */
4487 if (type == error_mark_node)
4488 continue;
4490 size_varies = 0;
4492 /* Warn about some types functions can't return. */
4494 if (TREE_CODE (type) == FUNCTION_TYPE)
4496 error ("`%s' declared as function returning a function", name);
4497 type = integer_type_node;
4499 if (TREE_CODE (type) == ARRAY_TYPE)
4501 error ("`%s' declared as function returning an array", name);
4502 type = integer_type_node;
4505 #ifndef TRADITIONAL_RETURN_FLOAT
4506 /* Traditionally, declaring return type float means double. */
4508 if (flag_traditional && TYPE_MAIN_VARIANT (type) == float_type_node)
4509 type = double_type_node;
4510 #endif /* TRADITIONAL_RETURN_FLOAT */
4512 /* Construct the function type and go to the next
4513 inner layer of declarator. */
4515 arg_types = grokparms (TREE_OPERAND (declarator, 1),
4516 funcdef_flag
4517 /* Say it's a definition
4518 only for the CALL_EXPR
4519 closest to the identifier. */
4520 && TREE_CODE (TREE_OPERAND (declarator, 0)) == IDENTIFIER_NODE);
4521 /* Type qualifiers before the return type of the function
4522 qualify the return type, not the function type. */
4523 if (type_quals)
4525 /* Type qualifiers on a function return type are normally
4526 permitted by the standard but have no effect, so give a
4527 warning at -W. Qualifiers on a void return type have
4528 meaning as a GNU extension, and are banned on function
4529 definitions in ISO C. FIXME: strictly we shouldn't
4530 pedwarn for qualified void return types except on function
4531 definitions, but not doing so could lead to the undesirable
4532 state of a "volatile void" function return type not being
4533 warned about, and a use of the function being compiled
4534 with GNU semantics, with no diagnostics under -pedantic. */
4535 if (VOID_TYPE_P (type) && pedantic && !in_system_header)
4536 pedwarn ("ISO C forbids qualified void function return type");
4537 else if (extra_warnings
4538 && !(VOID_TYPE_P (type)
4539 && type_quals == TYPE_QUAL_VOLATILE))
4540 warning ("type qualifiers ignored on function return type");
4542 type = c_build_qualified_type (type, type_quals);
4544 type_quals = TYPE_UNQUALIFIED;
4546 type = build_function_type (type, arg_types);
4547 declarator = TREE_OPERAND (declarator, 0);
4549 /* Set the TYPE_CONTEXTs for each tagged type which is local to
4550 the formal parameter list of this FUNCTION_TYPE to point to
4551 the FUNCTION_TYPE node itself. */
4554 register tree link;
4556 for (link = last_function_parm_tags;
4557 link;
4558 link = TREE_CHAIN (link))
4559 TYPE_CONTEXT (TREE_VALUE (link)) = type;
4562 else if (TREE_CODE (declarator) == INDIRECT_REF)
4564 /* Merge any constancy or volatility into the target type
4565 for the pointer. */
4567 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4568 && type_quals)
4569 pedwarn ("ISO C forbids qualified function types");
4570 if (type_quals)
4571 type = c_build_qualified_type (type, type_quals);
4572 type_quals = TYPE_UNQUALIFIED;
4573 size_varies = 0;
4575 type = build_pointer_type (type);
4577 /* Process a list of type modifier keywords
4578 (such as const or volatile) that were given inside the `*'. */
4580 if (TREE_TYPE (declarator))
4582 register tree typemodlist;
4583 int erred = 0;
4585 constp = 0;
4586 volatilep = 0;
4587 restrictp = 0;
4588 for (typemodlist = TREE_TYPE (declarator); typemodlist;
4589 typemodlist = TREE_CHAIN (typemodlist))
4591 tree qualifier = TREE_VALUE (typemodlist);
4593 if (C_IS_RESERVED_WORD (qualifier))
4595 if (C_RID_CODE (qualifier) == RID_CONST)
4596 constp++;
4597 else if (C_RID_CODE (qualifier) == RID_VOLATILE)
4598 volatilep++;
4599 else if (C_RID_CODE (qualifier) == RID_RESTRICT)
4600 restrictp++;
4601 else
4602 erred++;
4604 else
4605 erred++;
4608 if (erred)
4609 error ("invalid type modifier within pointer declarator");
4610 if (constp > 1 && ! flag_isoc99)
4611 pedwarn ("duplicate `const'");
4612 if (volatilep > 1 && ! flag_isoc99)
4613 pedwarn ("duplicate `volatile'");
4614 if (restrictp > 1 && ! flag_isoc99)
4615 pedwarn ("duplicate `restrict'");
4617 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4618 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4619 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4622 declarator = TREE_OPERAND (declarator, 0);
4624 else
4625 abort ();
4629 /* Now TYPE has the actual type. */
4631 /* Did array size calculations overflow? */
4633 if (TREE_CODE (type) == ARRAY_TYPE
4634 && COMPLETE_TYPE_P (type)
4635 && TREE_OVERFLOW (TYPE_SIZE (type)))
4637 error ("size of array `%s' is too large", name);
4638 /* If we proceed with the array type as it is, we'll eventully
4639 crash in tree_low_cst(). */
4640 type = error_mark_node;
4643 /* If this is declaring a typedef name, return a TYPE_DECL. */
4645 if (specbits & (1 << (int) RID_TYPEDEF))
4647 tree decl;
4648 /* Note that the grammar rejects storage classes
4649 in typenames, fields or parameters */
4650 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4651 && type_quals)
4652 pedwarn ("ISO C forbids qualified function types");
4653 if (type_quals)
4654 type = c_build_qualified_type (type, type_quals);
4655 decl = build_decl (TYPE_DECL, declarator, type);
4656 if ((specbits & (1 << (int) RID_SIGNED))
4657 || (typedef_decl && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
4658 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
4659 return decl;
4662 /* Detect the case of an array type of unspecified size
4663 which came, as such, direct from a typedef name.
4664 We must copy the type, so that each identifier gets
4665 a distinct type, so that each identifier's size can be
4666 controlled separately by its own initializer. */
4668 if (type != 0 && typedef_type != 0
4669 && TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == 0
4670 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (typedef_type))
4672 type = build_array_type (TREE_TYPE (type), 0);
4673 if (size_varies)
4674 C_TYPE_VARIABLE_SIZE (type) = 1;
4677 /* If this is a type name (such as, in a cast or sizeof),
4678 compute the type and return it now. */
4680 if (decl_context == TYPENAME)
4682 /* Note that the grammar rejects storage classes
4683 in typenames, fields or parameters */
4684 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4685 && type_quals)
4686 pedwarn ("ISO C forbids const or volatile function types");
4687 if (type_quals)
4688 type = c_build_qualified_type (type, type_quals);
4689 return type;
4692 /* Aside from typedefs and type names (handle above),
4693 `void' at top level (not within pointer)
4694 is allowed only in public variables.
4695 We don't complain about parms either, but that is because
4696 a better error message can be made later. */
4698 if (VOID_TYPE_P (type) && decl_context != PARM
4699 && ! ((decl_context != FIELD && TREE_CODE (type) != FUNCTION_TYPE)
4700 && ((specbits & (1 << (int) RID_EXTERN))
4701 || (current_binding_level == global_binding_level
4702 && !(specbits
4703 & ((1 << (int) RID_STATIC) | (1 << (int) RID_REGISTER)))))))
4705 error ("variable or field `%s' declared void", name);
4706 type = integer_type_node;
4709 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
4710 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
4713 register tree decl;
4715 if (decl_context == PARM)
4717 tree type_as_written;
4718 tree promoted_type;
4720 /* A parameter declared as an array of T is really a pointer to T.
4721 One declared as a function is really a pointer to a function. */
4723 if (TREE_CODE (type) == ARRAY_TYPE)
4725 /* Transfer const-ness of array into that of type pointed to. */
4726 type = TREE_TYPE (type);
4727 if (type_quals)
4728 type = c_build_qualified_type (type, type_quals);
4729 type = build_pointer_type (type);
4730 type_quals = TYPE_UNQUALIFIED;
4731 if (array_ptr_quals)
4733 tree new_ptr_quals, new_ptr_attrs;
4734 int erred = 0;
4735 split_specs_attrs (array_ptr_quals, &new_ptr_quals, &new_ptr_attrs);
4736 /* We don't yet implement attributes in this context. */
4737 if (new_ptr_attrs != NULL_TREE)
4738 warning ("attributes in parameter array declarator ignored");
4740 constp = 0;
4741 volatilep = 0;
4742 restrictp = 0;
4743 for (; new_ptr_quals; new_ptr_quals = TREE_CHAIN (new_ptr_quals))
4745 tree qualifier = TREE_VALUE (new_ptr_quals);
4747 if (C_IS_RESERVED_WORD (qualifier))
4749 if (C_RID_CODE (qualifier) == RID_CONST)
4750 constp++;
4751 else if (C_RID_CODE (qualifier) == RID_VOLATILE)
4752 volatilep++;
4753 else if (C_RID_CODE (qualifier) == RID_RESTRICT)
4754 restrictp++;
4755 else
4756 erred++;
4758 else
4759 erred++;
4762 if (erred)
4763 error ("invalid type modifier within array declarator");
4765 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4766 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4767 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4769 size_varies = 0;
4771 else if (TREE_CODE (type) == FUNCTION_TYPE)
4773 if (pedantic && type_quals)
4774 pedwarn ("ISO C forbids qualified function types");
4775 if (type_quals)
4776 type = c_build_qualified_type (type, type_quals);
4777 type = build_pointer_type (type);
4778 type_quals = TYPE_UNQUALIFIED;
4780 else if (type_quals)
4781 type = c_build_qualified_type (type, type_quals);
4783 type_as_written = type;
4785 decl = build_decl (PARM_DECL, declarator, type);
4786 if (size_varies)
4787 C_DECL_VARIABLE_SIZE (decl) = 1;
4789 /* Compute the type actually passed in the parmlist,
4790 for the case where there is no prototype.
4791 (For example, shorts and chars are passed as ints.)
4792 When there is a prototype, this is overridden later. */
4794 if (type == error_mark_node)
4795 promoted_type = type;
4796 else
4798 promoted_type = simple_type_promotes_to (type);
4799 if (! promoted_type)
4800 promoted_type = type;
4803 DECL_ARG_TYPE (decl) = promoted_type;
4804 DECL_ARG_TYPE_AS_WRITTEN (decl) = type_as_written;
4806 else if (decl_context == FIELD)
4808 /* Structure field. It may not be a function. */
4810 if (TREE_CODE (type) == FUNCTION_TYPE)
4812 error ("field `%s' declared as a function", name);
4813 type = build_pointer_type (type);
4815 else if (TREE_CODE (type) != ERROR_MARK
4816 && !COMPLETE_OR_UNBOUND_ARRAY_TYPE_P (type))
4818 error ("field `%s' has incomplete type", name);
4819 type = error_mark_node;
4821 /* Move type qualifiers down to element of an array. */
4822 if (TREE_CODE (type) == ARRAY_TYPE && type_quals)
4824 type = build_array_type (c_build_qualified_type (TREE_TYPE (type),
4825 type_quals),
4826 TYPE_DOMAIN (type));
4827 #if 0
4828 /* Leave the field const or volatile as well. */
4829 type_quals = TYPE_UNQUALIFIED;
4830 #endif
4832 decl = build_decl (FIELD_DECL, declarator, type);
4833 DECL_NONADDRESSABLE_P (decl) = bitfield;
4835 if (size_varies)
4836 C_DECL_VARIABLE_SIZE (decl) = 1;
4838 else if (TREE_CODE (type) == FUNCTION_TYPE)
4840 /* Every function declaration is "external"
4841 except for those which are inside a function body
4842 in which `auto' is used.
4843 That is a case not specified by ANSI C,
4844 and we use it for forward declarations for nested functions. */
4845 int extern_ref = (!(specbits & (1 << (int) RID_AUTO))
4846 || current_binding_level == global_binding_level);
4848 if (specbits & (1 << (int) RID_AUTO)
4849 && (pedantic || current_binding_level == global_binding_level))
4850 pedwarn ("invalid storage class for function `%s'", name);
4851 if (specbits & (1 << (int) RID_REGISTER))
4852 error ("invalid storage class for function `%s'", name);
4853 /* Function declaration not at top level.
4854 Storage classes other than `extern' are not allowed
4855 and `extern' makes no difference. */
4856 if (current_binding_level != global_binding_level
4857 && (specbits & ((1 << (int) RID_STATIC) | (1 << (int) RID_INLINE)))
4858 && pedantic)
4859 pedwarn ("invalid storage class for function `%s'", name);
4861 decl = build_decl (FUNCTION_DECL, declarator, type);
4862 decl = build_decl_attribute_variant (decl, decl_machine_attr);
4864 if (pedantic && type_quals && ! DECL_IN_SYSTEM_HEADER (decl))
4865 pedwarn ("ISO C forbids qualified function types");
4867 /* GNU C interprets a `volatile void' return type to indicate
4868 that the function does not return. */
4869 if ((type_quals & TYPE_QUAL_VOLATILE)
4870 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
4871 warning ("`noreturn' function returns non-void value");
4873 if (extern_ref)
4874 DECL_EXTERNAL (decl) = 1;
4875 /* Record absence of global scope for `static' or `auto'. */
4876 TREE_PUBLIC (decl)
4877 = !(specbits & ((1 << (int) RID_STATIC) | (1 << (int) RID_AUTO)));
4879 /* Record presence of `inline', if it is reasonable. */
4880 if (inlinep)
4882 if (MAIN_NAME_P (declarator))
4883 warning ("cannot inline function `main'");
4884 else
4885 /* Assume that otherwise the function can be inlined. */
4886 DECL_INLINE (decl) = 1;
4888 if (specbits & (1 << (int) RID_EXTERN))
4889 current_extern_inline = 1;
4892 else
4894 /* It's a variable. */
4895 /* An uninitialized decl with `extern' is a reference. */
4896 int extern_ref = !initialized && (specbits & (1 << (int) RID_EXTERN));
4898 /* Move type qualifiers down to element of an array. */
4899 if (TREE_CODE (type) == ARRAY_TYPE && type_quals)
4901 int saved_align = TYPE_ALIGN(type);
4902 type = build_array_type (c_build_qualified_type (TREE_TYPE (type),
4903 type_quals),
4904 TYPE_DOMAIN (type));
4905 TYPE_ALIGN (type) = saved_align;
4906 #if 0 /* Leave the variable const or volatile as well. */
4907 type_quals = TYPE_UNQUALIFIED;
4908 #endif
4910 else if (type_quals)
4911 type = c_build_qualified_type (type, type_quals);
4913 decl = build_decl (VAR_DECL, declarator, type);
4914 if (size_varies)
4915 C_DECL_VARIABLE_SIZE (decl) = 1;
4917 if (inlinep)
4918 pedwarn_with_decl (decl, "variable `%s' declared `inline'");
4920 DECL_EXTERNAL (decl) = extern_ref;
4921 /* At top level, the presence of a `static' or `register' storage
4922 class specifier, or the absence of all storage class specifiers
4923 makes this declaration a definition (perhaps tentative). Also,
4924 the absence of both `static' and `register' makes it public. */
4925 if (current_binding_level == global_binding_level)
4927 TREE_PUBLIC (decl)
4928 = !(specbits
4929 & ((1 << (int) RID_STATIC) | (1 << (int) RID_REGISTER)));
4930 TREE_STATIC (decl) = ! DECL_EXTERNAL (decl);
4932 /* Not at top level, only `static' makes a static definition. */
4933 else
4935 TREE_STATIC (decl) = (specbits & (1 << (int) RID_STATIC)) != 0;
4936 TREE_PUBLIC (decl) = DECL_EXTERNAL (decl);
4940 /* Record `register' declaration for warnings on &
4941 and in case doing stupid register allocation. */
4943 if (specbits & (1 << (int) RID_REGISTER))
4944 DECL_REGISTER (decl) = 1;
4946 /* Record constancy and volatility. */
4947 c_apply_type_quals_to_decl (type_quals, decl);
4949 /* If a type has volatile components, it should be stored in memory.
4950 Otherwise, the fact that those components are volatile
4951 will be ignored, and would even crash the compiler. */
4952 if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (decl)))
4953 mark_addressable (decl);
4955 return decl;
4959 /* Decode the parameter-list info for a function type or function definition.
4960 The argument is the value returned by `get_parm_info' (or made in parse.y
4961 if there is an identifier list instead of a parameter decl list).
4962 These two functions are separate because when a function returns
4963 or receives functions then each is called multiple times but the order
4964 of calls is different. The last call to `grokparms' is always the one
4965 that contains the formal parameter names of a function definition.
4967 Store in `last_function_parms' a chain of the decls of parms.
4968 Also store in `last_function_parm_tags' a chain of the struct, union,
4969 and enum tags declared among the parms.
4971 Return a list of arg types to use in the FUNCTION_TYPE for this function.
4973 FUNCDEF_FLAG is nonzero for a function definition, 0 for
4974 a mere declaration. A nonempty identifier-list gets an error message
4975 when FUNCDEF_FLAG is zero. */
4977 static tree
4978 grokparms (parms_info, funcdef_flag)
4979 tree parms_info;
4980 int funcdef_flag;
4982 tree first_parm = TREE_CHAIN (parms_info);
4984 last_function_parms = TREE_PURPOSE (parms_info);
4985 last_function_parm_tags = TREE_VALUE (parms_info);
4987 if (warn_strict_prototypes && first_parm == 0 && !funcdef_flag
4988 && !in_system_header)
4989 warning ("function declaration isn't a prototype");
4991 if (first_parm != 0
4992 && TREE_CODE (TREE_VALUE (first_parm)) == IDENTIFIER_NODE)
4994 if (! funcdef_flag)
4995 pedwarn ("parameter names (without types) in function declaration");
4997 last_function_parms = first_parm;
4998 return 0;
5000 else
5002 tree parm;
5003 tree typelt;
5004 /* We no longer test FUNCDEF_FLAG.
5005 If the arg types are incomplete in a declaration,
5006 they must include undefined tags.
5007 These tags can never be defined in the scope of the declaration,
5008 so the types can never be completed,
5009 and no call can be compiled successfully. */
5010 #if 0
5011 /* In a fcn definition, arg types must be complete. */
5012 if (funcdef_flag)
5013 #endif
5014 for (parm = last_function_parms, typelt = first_parm;
5015 parm;
5016 parm = TREE_CHAIN (parm))
5017 /* Skip over any enumeration constants declared here. */
5018 if (TREE_CODE (parm) == PARM_DECL)
5020 /* Barf if the parameter itself has an incomplete type. */
5021 tree type = TREE_VALUE (typelt);
5022 if (type == error_mark_node)
5023 continue;
5024 if (!COMPLETE_TYPE_P (type))
5026 if (funcdef_flag && DECL_NAME (parm) != 0)
5027 error ("parameter `%s' has incomplete type",
5028 IDENTIFIER_POINTER (DECL_NAME (parm)));
5029 else
5030 warning ("parameter has incomplete type");
5031 if (funcdef_flag)
5033 TREE_VALUE (typelt) = error_mark_node;
5034 TREE_TYPE (parm) = error_mark_node;
5037 #if 0
5038 /* This has been replaced by parm_tags_warning, which
5039 uses a more accurate criterion for what to warn
5040 about. */
5041 else
5043 /* Now warn if is a pointer to an incomplete type. */
5044 while (TREE_CODE (type) == POINTER_TYPE
5045 || TREE_CODE (type) == REFERENCE_TYPE)
5046 type = TREE_TYPE (type);
5047 type = TYPE_MAIN_VARIANT (type);
5048 if (!COMPLETE_TYPE_P (type))
5050 if (DECL_NAME (parm) != 0)
5051 warning ("parameter `%s' points to incomplete type",
5052 IDENTIFIER_POINTER (DECL_NAME (parm)));
5053 else
5054 warning ("parameter points to incomplete type");
5057 #endif
5058 typelt = TREE_CHAIN (typelt);
5061 return first_parm;
5065 /* Return a tree_list node with info on a parameter list just parsed.
5066 The TREE_PURPOSE is a chain of decls of those parms.
5067 The TREE_VALUE is a list of structure, union and enum tags defined.
5068 The TREE_CHAIN is a list of argument types to go in the FUNCTION_TYPE.
5069 This tree_list node is later fed to `grokparms'.
5071 VOID_AT_END nonzero means append `void' to the end of the type-list.
5072 Zero means the parmlist ended with an ellipsis so don't append `void'. */
5074 tree
5075 get_parm_info (void_at_end)
5076 int void_at_end;
5078 register tree decl, t;
5079 register tree types = 0;
5080 int erred = 0;
5081 tree tags = gettags ();
5082 tree parms = getdecls ();
5083 tree new_parms = 0;
5084 tree order = current_binding_level->parm_order;
5086 /* Just `void' (and no ellipsis) is special. There are really no parms.
5087 But if the `void' is qualified (by `const' or `volatile') or has a
5088 storage class specifier (`register'), then the behavior is undefined;
5089 by not counting it as the special case of `void' we will cause an
5090 error later. Typedefs for `void' are OK (see DR#157). */
5091 if (void_at_end && parms != 0
5092 && TREE_CHAIN (parms) == 0
5093 && VOID_TYPE_P (TREE_TYPE (parms))
5094 && ! TREE_THIS_VOLATILE (parms)
5095 && ! TREE_READONLY (parms)
5096 && ! DECL_REGISTER (parms)
5097 && DECL_NAME (parms) == 0)
5099 parms = NULL_TREE;
5100 storedecls (NULL_TREE);
5101 return tree_cons (NULL_TREE, NULL_TREE,
5102 tree_cons (NULL_TREE, void_type_node, NULL_TREE));
5105 /* Extract enumerator values and other non-parms declared with the parms.
5106 Likewise any forward parm decls that didn't have real parm decls. */
5107 for (decl = parms; decl;)
5109 tree next = TREE_CHAIN (decl);
5111 if (TREE_CODE (decl) != PARM_DECL)
5113 TREE_CHAIN (decl) = new_parms;
5114 new_parms = decl;
5116 else if (TREE_ASM_WRITTEN (decl))
5118 error_with_decl (decl,
5119 "parameter `%s' has just a forward declaration");
5120 TREE_CHAIN (decl) = new_parms;
5121 new_parms = decl;
5123 decl = next;
5126 /* Put the parm decls back in the order they were in in the parm list. */
5127 for (t = order; t; t = TREE_CHAIN (t))
5129 if (TREE_CHAIN (t))
5130 TREE_CHAIN (TREE_VALUE (t)) = TREE_VALUE (TREE_CHAIN (t));
5131 else
5132 TREE_CHAIN (TREE_VALUE (t)) = 0;
5135 new_parms = chainon (order ? nreverse (TREE_VALUE (order)) : 0,
5136 new_parms);
5138 /* Store the parmlist in the binding level since the old one
5139 is no longer a valid list. (We have changed the chain pointers.) */
5140 storedecls (new_parms);
5142 for (decl = new_parms; decl; decl = TREE_CHAIN (decl))
5143 /* There may also be declarations for enumerators if an enumeration
5144 type is declared among the parms. Ignore them here. */
5145 if (TREE_CODE (decl) == PARM_DECL)
5147 /* Since there is a prototype,
5148 args are passed in their declared types. */
5149 tree type = TREE_TYPE (decl);
5150 DECL_ARG_TYPE (decl) = type;
5151 if (PROMOTE_PROTOTYPES
5152 && INTEGRAL_TYPE_P (type)
5153 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
5154 DECL_ARG_TYPE (decl) = integer_type_node;
5156 types = tree_cons (NULL_TREE, TREE_TYPE (decl), types);
5157 if (VOID_TYPE_P (TREE_VALUE (types)) && ! erred
5158 && DECL_NAME (decl) == 0)
5160 error ("`void' in parameter list must be the entire list");
5161 erred = 1;
5165 if (void_at_end)
5166 return tree_cons (new_parms, tags,
5167 nreverse (tree_cons (NULL_TREE, void_type_node, types)));
5169 return tree_cons (new_parms, tags, nreverse (types));
5172 /* At end of parameter list, warn about any struct, union or enum tags
5173 defined within. Do so because these types cannot ever become complete. */
5175 void
5176 parmlist_tags_warning ()
5178 tree elt;
5179 static int already;
5181 for (elt = current_binding_level->tags; elt; elt = TREE_CHAIN (elt))
5183 enum tree_code code = TREE_CODE (TREE_VALUE (elt));
5184 /* An anonymous union parm type is meaningful as a GNU extension.
5185 So don't warn for that. */
5186 if (code == UNION_TYPE && TREE_PURPOSE (elt) == 0 && !pedantic)
5187 continue;
5188 if (TREE_PURPOSE (elt) != 0)
5189 warning ("`%s %s' declared inside parameter list",
5190 (code == RECORD_TYPE ? "struct"
5191 : code == UNION_TYPE ? "union"
5192 : "enum"),
5193 IDENTIFIER_POINTER (TREE_PURPOSE (elt)));
5194 else
5196 /* For translation these need to be seperate warnings */
5197 if (code == RECORD_TYPE)
5198 warning ("anonymous struct declared inside parameter list");
5199 else if (code == UNION_TYPE)
5200 warning ("anonymous union declared inside parameter list");
5201 else
5202 warning ("anonymous enum declared inside parameter list");
5204 if (! already)
5206 warning ("its scope is only this definition or declaration, which is probably not what you want.");
5207 already = 1;
5212 /* Get the struct, enum or union (CODE says which) with tag NAME.
5213 Define the tag as a forward-reference if it is not defined. */
5215 tree
5216 xref_tag (code, name)
5217 enum tree_code code;
5218 tree name;
5220 /* If a cross reference is requested, look up the type
5221 already defined for this tag and return it. */
5223 register tree ref = lookup_tag (code, name, current_binding_level, 0);
5224 /* If this is the right type of tag, return what we found.
5225 (This reference will be shadowed by shadow_tag later if appropriate.)
5226 If this is the wrong type of tag, do not return it. If it was the
5227 wrong type in the same binding level, we will have had an error
5228 message already; if in a different binding level and declaring
5229 a name, pending_xref_error will give an error message; but if in a
5230 different binding level and not declaring a name, this tag should
5231 shadow the previous declaration of a different type of tag, and
5232 this would not work properly if we return the reference found.
5233 (For example, with "struct foo" in an outer scope, "union foo;"
5234 must shadow that tag with a new one of union type.) */
5235 if (ref && TREE_CODE (ref) == code)
5236 return ref;
5238 /* If no such tag is yet defined, create a forward-reference node
5239 and record it as the "definition".
5240 When a real declaration of this type is found,
5241 the forward-reference will be altered into a real type. */
5243 ref = make_node (code);
5244 if (code == ENUMERAL_TYPE)
5246 /* Give the type a default layout like unsigned int
5247 to avoid crashing if it does not get defined. */
5248 TYPE_MODE (ref) = TYPE_MODE (unsigned_type_node);
5249 TYPE_ALIGN (ref) = TYPE_ALIGN (unsigned_type_node);
5250 TYPE_USER_ALIGN (ref) = 0;
5251 TREE_UNSIGNED (ref) = 1;
5252 TYPE_PRECISION (ref) = TYPE_PRECISION (unsigned_type_node);
5253 TYPE_MIN_VALUE (ref) = TYPE_MIN_VALUE (unsigned_type_node);
5254 TYPE_MAX_VALUE (ref) = TYPE_MAX_VALUE (unsigned_type_node);
5257 pushtag (name, ref);
5259 return ref;
5262 /* Make sure that the tag NAME is defined *in the current binding level*
5263 at least as a forward reference.
5264 CODE says which kind of tag NAME ought to be. */
5266 tree
5267 start_struct (code, name)
5268 enum tree_code code;
5269 tree name;
5271 /* If there is already a tag defined at this binding level
5272 (as a forward reference), just return it. */
5274 register tree ref = 0;
5276 if (name != 0)
5277 ref = lookup_tag (code, name, current_binding_level, 1);
5278 if (ref && TREE_CODE (ref) == code)
5280 C_TYPE_BEING_DEFINED (ref) = 1;
5281 TYPE_PACKED (ref) = flag_pack_struct;
5282 if (TYPE_FIELDS (ref))
5283 error ("redefinition of `%s %s'",
5284 code == UNION_TYPE ? "union" : "struct",
5285 IDENTIFIER_POINTER (name));
5287 return ref;
5290 /* Otherwise create a forward-reference just so the tag is in scope. */
5292 ref = make_node (code);
5293 pushtag (name, ref);
5294 C_TYPE_BEING_DEFINED (ref) = 1;
5295 TYPE_PACKED (ref) = flag_pack_struct;
5296 return ref;
5299 /* Process the specs, declarator (NULL if omitted) and width (NULL if omitted)
5300 of a structure component, returning a FIELD_DECL node.
5301 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node.
5303 This is done during the parsing of the struct declaration.
5304 The FIELD_DECL nodes are chained together and the lot of them
5305 are ultimately passed to `build_struct' to make the RECORD_TYPE node. */
5307 tree
5308 grokfield (filename, line, declarator, declspecs, width)
5309 const char *filename ATTRIBUTE_UNUSED;
5310 int line ATTRIBUTE_UNUSED;
5311 tree declarator, declspecs, width;
5313 tree value;
5315 value = grokdeclarator (declarator, declspecs, width ? BITFIELD : FIELD, 0);
5317 finish_decl (value, NULL_TREE, NULL_TREE);
5318 DECL_INITIAL (value) = width;
5320 maybe_objc_check_decl (value);
5321 return value;
5324 /* Fill in the fields of a RECORD_TYPE or UNION_TYPE node, T.
5325 FIELDLIST is a chain of FIELD_DECL nodes for the fields.
5326 ATTRIBUTES are attributes to be applied to the structure. */
5328 tree
5329 finish_struct (t, fieldlist, attributes)
5330 tree t;
5331 tree fieldlist;
5332 tree attributes;
5334 register tree x;
5335 int toplevel = global_binding_level == current_binding_level;
5336 int saw_named_field;
5338 /* If this type was previously laid out as a forward reference,
5339 make sure we lay it out again. */
5341 TYPE_SIZE (t) = 0;
5343 decl_attributes (t, attributes);
5345 /* Nameless union parm types are useful as GCC extension. */
5346 if (! (TREE_CODE (t) == UNION_TYPE && TYPE_NAME (t) == 0) && !pedantic)
5347 /* Otherwise, warn about any struct or union def. in parmlist. */
5348 if (in_parm_level_p ())
5350 if (pedantic)
5351 pedwarn ("%s defined inside parms",
5352 TREE_CODE (t) == UNION_TYPE ? _("union") : _("structure"));
5353 else if (! flag_traditional)
5354 warning ("%s defined inside parms",
5355 TREE_CODE (t) == UNION_TYPE ? _("union") : _("structure"));
5358 if (pedantic)
5360 for (x = fieldlist; x; x = TREE_CHAIN (x))
5361 if (DECL_NAME (x) != 0)
5362 break;
5364 if (x == 0)
5365 pedwarn ("%s has no %s",
5366 TREE_CODE (t) == UNION_TYPE ? _("union") : _("struct"),
5367 fieldlist ? _("named members") : _("members"));
5370 /* Install struct as DECL_CONTEXT of each field decl.
5371 Also process specified field sizes,m which is found in the DECL_INITIAL.
5372 Store 0 there, except for ": 0" fields (so we can find them
5373 and delete them, below). */
5375 saw_named_field = 0;
5376 for (x = fieldlist; x; x = TREE_CHAIN (x))
5378 DECL_CONTEXT (x) = t;
5379 DECL_PACKED (x) |= TYPE_PACKED (t);
5381 /* If any field is const, the structure type is pseudo-const. */
5382 if (TREE_READONLY (x))
5383 C_TYPE_FIELDS_READONLY (t) = 1;
5384 else
5386 /* A field that is pseudo-const makes the structure likewise. */
5387 tree t1 = TREE_TYPE (x);
5388 while (TREE_CODE (t1) == ARRAY_TYPE)
5389 t1 = TREE_TYPE (t1);
5390 if ((TREE_CODE (t1) == RECORD_TYPE || TREE_CODE (t1) == UNION_TYPE)
5391 && C_TYPE_FIELDS_READONLY (t1))
5392 C_TYPE_FIELDS_READONLY (t) = 1;
5395 /* Any field that is volatile means variables of this type must be
5396 treated in some ways as volatile. */
5397 if (TREE_THIS_VOLATILE (x))
5398 C_TYPE_FIELDS_VOLATILE (t) = 1;
5400 /* Any field of nominal variable size implies structure is too. */
5401 if (C_DECL_VARIABLE_SIZE (x))
5402 C_TYPE_VARIABLE_SIZE (t) = 1;
5404 /* Detect invalid nested redefinition. */
5405 if (TREE_TYPE (x) == t)
5406 error ("nested redefinition of `%s'",
5407 IDENTIFIER_POINTER (TYPE_NAME (t)));
5409 /* Detect invalid bit-field size. */
5410 if (DECL_INITIAL (x))
5411 STRIP_NOPS (DECL_INITIAL (x));
5412 if (DECL_INITIAL (x))
5414 if (TREE_CODE (DECL_INITIAL (x)) == INTEGER_CST)
5415 constant_expression_warning (DECL_INITIAL (x));
5416 else
5418 error_with_decl (x,
5419 "bit-field `%s' width not an integer constant");
5420 DECL_INITIAL (x) = NULL;
5424 /* Detect invalid bit-field type. */
5425 if (DECL_INITIAL (x)
5426 && TREE_CODE (TREE_TYPE (x)) != INTEGER_TYPE
5427 && TREE_CODE (TREE_TYPE (x)) != BOOLEAN_TYPE
5428 && TREE_CODE (TREE_TYPE (x)) != ENUMERAL_TYPE)
5430 error_with_decl (x, "bit-field `%s' has invalid type");
5431 DECL_INITIAL (x) = NULL;
5434 if (DECL_INITIAL (x) && pedantic
5435 && TYPE_MAIN_VARIANT (TREE_TYPE (x)) != integer_type_node
5436 && TYPE_MAIN_VARIANT (TREE_TYPE (x)) != unsigned_type_node
5437 && TYPE_MAIN_VARIANT (TREE_TYPE (x)) != c_bool_type_node
5438 /* Accept an enum that's equivalent to int or unsigned int. */
5439 && !(TREE_CODE (TREE_TYPE (x)) == ENUMERAL_TYPE
5440 && (TYPE_PRECISION (TREE_TYPE (x))
5441 == TYPE_PRECISION (integer_type_node))))
5442 pedwarn_with_decl (x, "bit-field `%s' type invalid in ISO C");
5444 /* Detect and ignore out of range field width and process valid
5445 field widths. */
5446 if (DECL_INITIAL (x))
5448 int max_width;
5449 if (TYPE_MAIN_VARIANT (TREE_TYPE (x)) == c_bool_type_node)
5450 max_width = CHAR_TYPE_SIZE;
5451 else
5452 max_width = TYPE_PRECISION (TREE_TYPE (x));
5453 if (tree_int_cst_sgn (DECL_INITIAL (x)) < 0)
5454 error_with_decl (x, "negative width in bit-field `%s'");
5455 else if (0 < compare_tree_int (DECL_INITIAL (x), max_width))
5456 pedwarn_with_decl (x, "width of `%s' exceeds its type");
5457 else if (integer_zerop (DECL_INITIAL (x)) && DECL_NAME (x) != 0)
5458 error_with_decl (x, "zero width for bit-field `%s'");
5459 else
5461 /* The test above has assured us that TREE_INT_CST_HIGH is 0. */
5462 unsigned HOST_WIDE_INT width
5463 = TREE_INT_CST_LOW (DECL_INITIAL (x));
5465 if (TREE_CODE (TREE_TYPE (x)) == ENUMERAL_TYPE
5466 && (width < min_precision (TYPE_MIN_VALUE (TREE_TYPE (x)),
5467 TREE_UNSIGNED (TREE_TYPE (x)))
5468 || (width
5469 < min_precision (TYPE_MAX_VALUE (TREE_TYPE (x)),
5470 TREE_UNSIGNED (TREE_TYPE (x))))))
5471 warning_with_decl (x,
5472 "`%s' is narrower than values of its type");
5474 DECL_SIZE (x) = bitsize_int (width);
5475 DECL_BIT_FIELD (x) = 1;
5476 SET_DECL_C_BIT_FIELD (x);
5478 if (width == 0)
5480 /* field size 0 => force desired amount of alignment. */
5481 #ifdef EMPTY_FIELD_BOUNDARY
5482 DECL_ALIGN (x) = MAX (DECL_ALIGN (x), EMPTY_FIELD_BOUNDARY);
5483 #endif
5484 #ifdef PCC_BITFIELD_TYPE_MATTERS
5485 if (PCC_BITFIELD_TYPE_MATTERS)
5487 DECL_ALIGN (x) = MAX (DECL_ALIGN (x),
5488 TYPE_ALIGN (TREE_TYPE (x)));
5489 DECL_USER_ALIGN (x) |= TYPE_USER_ALIGN (TREE_TYPE (x));
5491 #endif
5496 else if (TREE_TYPE (x) != error_mark_node)
5498 unsigned int min_align = (DECL_PACKED (x) ? BITS_PER_UNIT
5499 : TYPE_ALIGN (TREE_TYPE (x)));
5501 /* Non-bit-fields are aligned for their type, except packed
5502 fields which require only BITS_PER_UNIT alignment. */
5503 DECL_ALIGN (x) = MAX (DECL_ALIGN (x), min_align);
5504 if (! DECL_PACKED (x))
5505 DECL_USER_ALIGN (x) |= TYPE_USER_ALIGN (TREE_TYPE (x));
5508 DECL_INITIAL (x) = 0;
5510 /* Detect flexible array member in an invalid context. */
5511 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
5512 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
5513 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
5514 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
5516 if (TREE_CODE (t) == UNION_TYPE)
5517 error_with_decl (x, "flexible array member in union");
5518 else if (TREE_CHAIN (x) != NULL_TREE)
5519 error_with_decl (x, "flexible array member not at end of struct");
5520 else if (! saw_named_field)
5521 error_with_decl (x, "flexible array member in otherwise empty struct");
5523 if (DECL_NAME (x))
5524 saw_named_field = 1;
5527 /* Delete all duplicate fields from the fieldlist */
5528 for (x = fieldlist; x && TREE_CHAIN (x);)
5529 /* Anonymous fields aren't duplicates. */
5530 if (DECL_NAME (TREE_CHAIN (x)) == 0)
5531 x = TREE_CHAIN (x);
5532 else
5534 register tree y = fieldlist;
5536 while (1)
5538 if (DECL_NAME (y) == DECL_NAME (TREE_CHAIN (x)))
5539 break;
5540 if (y == x)
5541 break;
5542 y = TREE_CHAIN (y);
5544 if (DECL_NAME (y) == DECL_NAME (TREE_CHAIN (x)))
5546 error_with_decl (TREE_CHAIN (x), "duplicate member `%s'");
5547 TREE_CHAIN (x) = TREE_CHAIN (TREE_CHAIN (x));
5549 else
5550 x = TREE_CHAIN (x);
5553 /* Now we have the nearly final fieldlist. Record it,
5554 then lay out the structure or union (including the fields). */
5556 TYPE_FIELDS (t) = fieldlist;
5558 layout_type (t);
5560 /* Delete all zero-width bit-fields from the fieldlist */
5562 tree *fieldlistp = &fieldlist;
5563 while (*fieldlistp)
5564 if (TREE_CODE (*fieldlistp) == FIELD_DECL && DECL_INITIAL (*fieldlistp))
5565 *fieldlistp = TREE_CHAIN (*fieldlistp);
5566 else
5567 fieldlistp = &TREE_CHAIN (*fieldlistp);
5570 /* Now we have the truly final field list.
5571 Store it in this type and in the variants. */
5573 TYPE_FIELDS (t) = fieldlist;
5575 for (x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
5577 TYPE_FIELDS (x) = TYPE_FIELDS (t);
5578 TYPE_LANG_SPECIFIC (x) = TYPE_LANG_SPECIFIC (t);
5579 TYPE_ALIGN (x) = TYPE_ALIGN (t);
5580 TYPE_USER_ALIGN (x) = TYPE_USER_ALIGN (t);
5583 /* If this was supposed to be a transparent union, but we can't
5584 make it one, warn and turn off the flag. */
5585 if (TREE_CODE (t) == UNION_TYPE
5586 && TYPE_TRANSPARENT_UNION (t)
5587 && TYPE_MODE (t) != DECL_MODE (TYPE_FIELDS (t)))
5589 TYPE_TRANSPARENT_UNION (t) = 0;
5590 warning ("union cannot be made transparent");
5593 /* If this structure or union completes the type of any previous
5594 variable declaration, lay it out and output its rtl. */
5596 if (current_binding_level->n_incomplete != 0)
5598 tree decl;
5599 for (decl = current_binding_level->names; decl; decl = TREE_CHAIN (decl))
5601 if (TYPE_MAIN_VARIANT (TREE_TYPE (decl)) == TYPE_MAIN_VARIANT (t)
5602 && TREE_CODE (decl) != TYPE_DECL)
5604 layout_decl (decl, 0);
5605 /* This is a no-op in c-lang.c or something real in objc-actions.c. */
5606 maybe_objc_check_decl (decl);
5607 rest_of_decl_compilation (decl, NULL, toplevel, 0);
5608 if (! toplevel)
5609 expand_decl (decl);
5610 --current_binding_level->n_incomplete;
5612 else if (!COMPLETE_TYPE_P (TREE_TYPE (decl))
5613 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
5615 tree element = TREE_TYPE (decl);
5616 while (TREE_CODE (element) == ARRAY_TYPE)
5617 element = TREE_TYPE (element);
5618 if (element == t)
5619 layout_array_type (TREE_TYPE (decl));
5624 /* Finish debugging output for this type. */
5625 rest_of_type_compilation (t, toplevel);
5627 return t;
5630 /* Lay out the type T, and its element type, and so on. */
5632 static void
5633 layout_array_type (t)
5634 tree t;
5636 if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
5637 layout_array_type (TREE_TYPE (t));
5638 layout_type (t);
5641 /* Begin compiling the definition of an enumeration type.
5642 NAME is its name (or null if anonymous).
5643 Returns the type object, as yet incomplete.
5644 Also records info about it so that build_enumerator
5645 may be used to declare the individual values as they are read. */
5647 tree
5648 start_enum (name)
5649 tree name;
5651 register tree enumtype = 0;
5653 /* If this is the real definition for a previous forward reference,
5654 fill in the contents in the same object that used to be the
5655 forward reference. */
5657 if (name != 0)
5658 enumtype = lookup_tag (ENUMERAL_TYPE, name, current_binding_level, 1);
5660 if (enumtype == 0 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
5662 enumtype = make_node (ENUMERAL_TYPE);
5663 pushtag (name, enumtype);
5666 C_TYPE_BEING_DEFINED (enumtype) = 1;
5668 if (TYPE_VALUES (enumtype) != 0)
5670 /* This enum is a named one that has been declared already. */
5671 error ("redeclaration of `enum %s'", IDENTIFIER_POINTER (name));
5673 /* Completely replace its old definition.
5674 The old enumerators remain defined, however. */
5675 TYPE_VALUES (enumtype) = 0;
5678 enum_next_value = integer_zero_node;
5679 enum_overflow = 0;
5681 if (flag_short_enums)
5682 TYPE_PACKED (enumtype) = 1;
5684 return enumtype;
5687 /* After processing and defining all the values of an enumeration type,
5688 install their decls in the enumeration type and finish it off.
5689 ENUMTYPE is the type object, VALUES a list of decl-value pairs,
5690 and ATTRIBUTES are the specified attributes.
5691 Returns ENUMTYPE. */
5693 tree
5694 finish_enum (enumtype, values, attributes)
5695 tree enumtype;
5696 tree values;
5697 tree attributes;
5699 register tree pair, tem;
5700 tree minnode = 0, maxnode = 0, enum_value_type;
5701 int precision, unsign;
5702 int toplevel = (global_binding_level == current_binding_level);
5704 if (in_parm_level_p ())
5705 warning ("enum defined inside parms");
5707 decl_attributes (enumtype, attributes);
5709 /* Calculate the maximum value of any enumerator in this type. */
5711 if (values == error_mark_node)
5712 minnode = maxnode = integer_zero_node;
5713 else
5715 minnode = maxnode = TREE_VALUE (values);
5716 for (pair = TREE_CHAIN (values); pair; pair = TREE_CHAIN (pair))
5718 tree value = TREE_VALUE (pair);
5719 if (tree_int_cst_lt (maxnode, value))
5720 maxnode = value;
5721 if (tree_int_cst_lt (value, minnode))
5722 minnode = value;
5726 /* Construct the final type of this enumeration. It is the same
5727 as one of the integral types - the narrowest one that fits, except
5728 that normally we only go as narrow as int - and signed iff any of
5729 the values are negative. */
5730 unsign = (tree_int_cst_sgn (minnode) >= 0);
5731 precision = MAX (min_precision (minnode, unsign),
5732 min_precision (maxnode, unsign));
5733 if (TYPE_PACKED (enumtype) || precision > TYPE_PRECISION (integer_type_node))
5735 tree narrowest = type_for_size (precision, unsign);
5736 if (narrowest == 0)
5738 warning ("enumeration values exceed range of largest integer");
5739 narrowest = long_long_integer_type_node;
5742 precision = TYPE_PRECISION (narrowest);
5744 else
5745 precision = TYPE_PRECISION (integer_type_node);
5747 if (precision == TYPE_PRECISION (integer_type_node))
5748 enum_value_type = type_for_size (precision, 0);
5749 else
5750 enum_value_type = enumtype;
5752 TYPE_MIN_VALUE (enumtype) = minnode;
5753 TYPE_MAX_VALUE (enumtype) = maxnode;
5754 TYPE_PRECISION (enumtype) = precision;
5755 TREE_UNSIGNED (enumtype) = unsign;
5756 TYPE_SIZE (enumtype) = 0;
5757 layout_type (enumtype);
5759 if (values != error_mark_node)
5761 /* Change the type of the enumerators to be the enum type. We
5762 need to do this irrespective of the size of the enum, for
5763 proper type checking. Replace the DECL_INITIALs of the
5764 enumerators, and the value slots of the list, with copies
5765 that have the enum type; they cannot be modified in place
5766 because they may be shared (e.g. integer_zero_node) Finally,
5767 change the purpose slots to point to the names of the decls. */
5768 for (pair = values; pair; pair = TREE_CHAIN (pair))
5770 tree enu = TREE_PURPOSE (pair);
5772 TREE_TYPE (enu) = enumtype;
5773 DECL_SIZE (enu) = TYPE_SIZE (enumtype);
5774 DECL_SIZE_UNIT (enu) = TYPE_SIZE_UNIT (enumtype);
5775 DECL_ALIGN (enu) = TYPE_ALIGN (enumtype);
5776 DECL_USER_ALIGN (enu) = TYPE_USER_ALIGN (enumtype);
5777 DECL_MODE (enu) = TYPE_MODE (enumtype);
5779 /* The ISO C Standard mandates enumerators to have type int,
5780 even though the underlying type of an enum type is
5781 unspecified. Here we convert any enumerators that fit in
5782 an int to type int, to avoid promotions to unsigned types
5783 when comparing integers with enumerators that fit in the
5784 int range. When -pedantic is given, build_enumerator()
5785 would have already taken care of those that don't fit. */
5786 if (int_fits_type_p (DECL_INITIAL (enu), enum_value_type))
5787 DECL_INITIAL (enu) = convert (enum_value_type, DECL_INITIAL (enu));
5788 else
5789 DECL_INITIAL (enu) = convert (enumtype, DECL_INITIAL (enu));
5791 TREE_PURPOSE (pair) = DECL_NAME (enu);
5792 TREE_VALUE (pair) = DECL_INITIAL (enu);
5795 TYPE_VALUES (enumtype) = values;
5798 /* Fix up all variant types of this enum type. */
5799 for (tem = TYPE_MAIN_VARIANT (enumtype); tem; tem = TYPE_NEXT_VARIANT (tem))
5801 if (tem == enumtype)
5802 continue;
5803 TYPE_VALUES (tem) = TYPE_VALUES (enumtype);
5804 TYPE_MIN_VALUE (tem) = TYPE_MIN_VALUE (enumtype);
5805 TYPE_MAX_VALUE (tem) = TYPE_MAX_VALUE (enumtype);
5806 TYPE_SIZE (tem) = TYPE_SIZE (enumtype);
5807 TYPE_SIZE_UNIT (tem) = TYPE_SIZE_UNIT (enumtype);
5808 TYPE_MODE (tem) = TYPE_MODE (enumtype);
5809 TYPE_PRECISION (tem) = TYPE_PRECISION (enumtype);
5810 TYPE_ALIGN (tem) = TYPE_ALIGN (enumtype);
5811 TYPE_USER_ALIGN (tem) = TYPE_USER_ALIGN (enumtype);
5812 TREE_UNSIGNED (tem) = TREE_UNSIGNED (enumtype);
5815 /* Finish debugging output for this type. */
5816 rest_of_type_compilation (enumtype, toplevel);
5818 return enumtype;
5821 /* Build and install a CONST_DECL for one value of the
5822 current enumeration type (one that was begun with start_enum).
5823 Return a tree-list containing the CONST_DECL and its value.
5824 Assignment of sequential values by default is handled here. */
5826 tree
5827 build_enumerator (name, value)
5828 tree name, value;
5830 register tree decl, type;
5832 /* Validate and default VALUE. */
5834 /* Remove no-op casts from the value. */
5835 if (value)
5836 STRIP_TYPE_NOPS (value);
5838 if (value != 0)
5840 if (TREE_CODE (value) == INTEGER_CST)
5842 value = default_conversion (value);
5843 constant_expression_warning (value);
5845 else
5847 error ("enumerator value for `%s' not integer constant",
5848 IDENTIFIER_POINTER (name));
5849 value = 0;
5853 /* Default based on previous value. */
5854 /* It should no longer be possible to have NON_LVALUE_EXPR
5855 in the default. */
5856 if (value == 0)
5858 value = enum_next_value;
5859 if (enum_overflow)
5860 error ("overflow in enumeration values");
5863 if (pedantic && ! int_fits_type_p (value, integer_type_node))
5865 pedwarn ("ISO C restricts enumerator values to range of `int'");
5866 value = convert (integer_type_node, value);
5869 /* Set basis for default for next value. */
5870 enum_next_value = build_binary_op (PLUS_EXPR, value, integer_one_node, 0);
5871 enum_overflow = tree_int_cst_lt (enum_next_value, value);
5873 /* Now create a declaration for the enum value name. */
5875 type = TREE_TYPE (value);
5876 type = type_for_size (MAX (TYPE_PRECISION (type),
5877 TYPE_PRECISION (integer_type_node)),
5878 ((flag_traditional
5879 || TYPE_PRECISION (type) >= TYPE_PRECISION (integer_type_node))
5880 && TREE_UNSIGNED (type)));
5882 decl = build_decl (CONST_DECL, name, type);
5883 DECL_INITIAL (decl) = convert (type, value);
5884 pushdecl (decl);
5886 return tree_cons (decl, value, NULL_TREE);
5890 /* Create the FUNCTION_DECL for a function definition.
5891 DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of
5892 the declaration; they describe the function's name and the type it returns,
5893 but twisted together in a fashion that parallels the syntax of C.
5895 This function creates a binding context for the function body
5896 as well as setting up the FUNCTION_DECL in current_function_decl.
5898 Returns 1 on success. If the DECLARATOR is not suitable for a function
5899 (it defines a datum instead), we return 0, which tells
5900 yyparse to report a parse error. */
5903 start_function (declspecs, declarator, attributes)
5904 tree declarator, declspecs, attributes;
5906 tree decl1, old_decl;
5907 tree restype;
5908 int old_immediate_size_expand = immediate_size_expand;
5910 current_function_returns_value = 0; /* Assume, until we see it does. */
5911 current_function_returns_null = 0;
5912 warn_about_return_type = 0;
5913 current_extern_inline = 0;
5914 c_function_varargs = 0;
5915 named_labels = 0;
5916 shadowed_labels = 0;
5918 /* Don't expand any sizes in the return type of the function. */
5919 immediate_size_expand = 0;
5921 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, 1);
5923 /* If the declarator is not suitable for a function definition,
5924 cause a syntax error. */
5925 if (decl1 == 0)
5927 immediate_size_expand = old_immediate_size_expand;
5928 return 0;
5931 decl_attributes (decl1, attributes);
5933 announce_function (decl1);
5935 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl1))))
5937 error ("return type is an incomplete type");
5938 /* Make it return void instead. */
5939 TREE_TYPE (decl1)
5940 = build_function_type (void_type_node,
5941 TYPE_ARG_TYPES (TREE_TYPE (decl1)));
5944 if (warn_about_return_type)
5945 pedwarn_c99 ("return type defaults to `int'");
5947 /* Save the parm names or decls from this function's declarator
5948 where store_parm_decls will find them. */
5949 current_function_parms = last_function_parms;
5950 current_function_parm_tags = last_function_parm_tags;
5952 /* Make the init_value nonzero so pushdecl knows this is not tentative.
5953 error_mark_node is replaced below (in poplevel) with the BLOCK. */
5954 DECL_INITIAL (decl1) = error_mark_node;
5956 /* If this definition isn't a prototype and we had a prototype declaration
5957 before, copy the arg type info from that prototype.
5958 But not if what we had before was a builtin function. */
5959 old_decl = lookup_name_current_level (DECL_NAME (decl1));
5960 if (old_decl != 0 && TREE_CODE (TREE_TYPE (old_decl)) == FUNCTION_TYPE
5961 && !DECL_BUILT_IN (old_decl)
5962 && (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
5963 == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (old_decl))))
5964 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0)
5966 TREE_TYPE (decl1) = TREE_TYPE (old_decl);
5967 current_function_prototype_file = DECL_SOURCE_FILE (old_decl);
5968 current_function_prototype_line = DECL_SOURCE_LINE (old_decl);
5971 /* If there is no explicit declaration, look for any out-of-scope implicit
5972 declarations. */
5973 if (old_decl == 0)
5974 old_decl = IDENTIFIER_IMPLICIT_DECL (DECL_NAME (decl1));
5976 /* Optionally warn of old-fashioned def with no previous prototype. */
5977 if (warn_strict_prototypes
5978 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0
5979 && !(old_decl != 0
5980 && (TYPE_ARG_TYPES (TREE_TYPE (old_decl)) != 0
5981 || (DECL_BUILT_IN (old_decl)
5982 && ! C_DECL_ANTICIPATED (old_decl)))))
5983 warning ("function declaration isn't a prototype");
5984 /* Optionally warn of any global def with no previous prototype. */
5985 else if (warn_missing_prototypes
5986 && TREE_PUBLIC (decl1)
5987 && !(old_decl != 0
5988 && (TYPE_ARG_TYPES (TREE_TYPE (old_decl)) != 0
5989 || (DECL_BUILT_IN (old_decl)
5990 && ! C_DECL_ANTICIPATED (old_decl))))
5991 && ! MAIN_NAME_P (DECL_NAME (decl1)))
5992 warning_with_decl (decl1, "no previous prototype for `%s'");
5993 /* Optionally warn of any def with no previous prototype
5994 if the function has already been used. */
5995 else if (warn_missing_prototypes
5996 && old_decl != 0 && TREE_USED (old_decl)
5997 && TYPE_ARG_TYPES (TREE_TYPE (old_decl)) == 0)
5998 warning_with_decl (decl1,
5999 "`%s' was used with no prototype before its definition");
6000 /* Optionally warn of any global def with no previous declaration. */
6001 else if (warn_missing_declarations
6002 && TREE_PUBLIC (decl1)
6003 && old_decl == 0
6004 && ! MAIN_NAME_P (DECL_NAME (decl1)))
6005 warning_with_decl (decl1, "no previous declaration for `%s'");
6006 /* Optionally warn of any def with no previous declaration
6007 if the function has already been used. */
6008 else if (warn_missing_declarations
6009 && old_decl != 0 && TREE_USED (old_decl)
6010 && old_decl == IDENTIFIER_IMPLICIT_DECL (DECL_NAME (decl1)))
6011 warning_with_decl (decl1,
6012 "`%s' was used with no declaration before its definition");
6014 /* This is a definition, not a reference.
6015 So normally clear DECL_EXTERNAL.
6016 However, `extern inline' acts like a declaration
6017 except for defining how to inline. So set DECL_EXTERNAL in that case. */
6018 DECL_EXTERNAL (decl1) = current_extern_inline;
6020 /* This function exists in static storage.
6021 (This does not mean `static' in the C sense!) */
6022 TREE_STATIC (decl1) = 1;
6024 /* A nested function is not global. */
6025 if (current_function_decl != 0)
6026 TREE_PUBLIC (decl1) = 0;
6028 /* Warn for unlikely, improbable, or stupid declarations of `main'. */
6029 if (warn_main > 0 && MAIN_NAME_P (DECL_NAME (decl1)))
6031 tree args;
6032 int argct = 0;
6034 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
6035 != integer_type_node)
6036 pedwarn_with_decl (decl1, "return type of `%s' is not `int'");
6038 for (args = TYPE_ARG_TYPES (TREE_TYPE (decl1)); args;
6039 args = TREE_CHAIN (args))
6041 tree type = args ? TREE_VALUE (args) : 0;
6043 if (type == void_type_node)
6044 break;
6046 ++argct;
6047 switch (argct)
6049 case 1:
6050 if (TYPE_MAIN_VARIANT (type) != integer_type_node)
6051 pedwarn_with_decl (decl1,
6052 "first argument of `%s' should be `int'");
6053 break;
6055 case 2:
6056 if (TREE_CODE (type) != POINTER_TYPE
6057 || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
6058 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
6059 != char_type_node))
6060 pedwarn_with_decl (decl1,
6061 "second argument of `%s' should be `char **'");
6062 break;
6064 case 3:
6065 if (TREE_CODE (type) != POINTER_TYPE
6066 || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
6067 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
6068 != char_type_node))
6069 pedwarn_with_decl (decl1,
6070 "third argument of `%s' should probably be `char **'");
6071 break;
6075 /* It is intentional that this message does not mention the third
6076 argument because it's only mentioned in an appendix of the
6077 standard. */
6078 if (argct > 0 && (argct < 2 || argct > 3))
6079 pedwarn_with_decl (decl1, "`%s' takes only zero or two arguments");
6081 if (! TREE_PUBLIC (decl1))
6082 pedwarn_with_decl (decl1, "`%s' is normally a non-static function");
6085 /* Record the decl so that the function name is defined.
6086 If we already have a decl for this name, and it is a FUNCTION_DECL,
6087 use the old decl. */
6089 current_function_decl = pushdecl (decl1);
6091 pushlevel (0);
6092 declare_parm_level (1);
6093 current_binding_level->subblocks_tag_transparent = 1;
6095 make_decl_rtl (current_function_decl, NULL);
6097 restype = TREE_TYPE (TREE_TYPE (current_function_decl));
6098 /* Promote the value to int before returning it. */
6099 if (c_promoting_integer_type_p (restype))
6101 /* It retains unsignedness if traditional
6102 or if not really getting wider. */
6103 if (TREE_UNSIGNED (restype)
6104 && (flag_traditional
6105 || (TYPE_PRECISION (restype)
6106 == TYPE_PRECISION (integer_type_node))))
6107 restype = unsigned_type_node;
6108 else
6109 restype = integer_type_node;
6111 DECL_RESULT (current_function_decl)
6112 = build_decl (RESULT_DECL, NULL_TREE, restype);
6114 /* If this fcn was already referenced via a block-scope `extern' decl
6115 (or an implicit decl), propagate certain information about the usage. */
6116 if (TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (current_function_decl)))
6117 TREE_ADDRESSABLE (current_function_decl) = 1;
6119 immediate_size_expand = old_immediate_size_expand;
6121 start_fname_decls ();
6123 return 1;
6126 /* Record that this function is going to be a varargs function.
6127 This is called before store_parm_decls, which is too early
6128 to call mark_varargs directly. */
6130 void
6131 c_mark_varargs ()
6133 c_function_varargs = 1;
6136 /* Store the parameter declarations into the current function declaration.
6137 This is called after parsing the parameter declarations, before
6138 digesting the body of the function.
6140 For an old-style definition, modify the function's type
6141 to specify at least the number of arguments. */
6143 void
6144 store_parm_decls ()
6146 register tree fndecl = current_function_decl;
6147 register tree parm;
6149 /* This is either a chain of PARM_DECLs (if a prototype was used)
6150 or a list of IDENTIFIER_NODEs (for an old-fashioned C definition). */
6151 tree specparms = current_function_parms;
6153 /* This is a list of types declared among parms in a prototype. */
6154 tree parmtags = current_function_parm_tags;
6156 /* This is a chain of PARM_DECLs from old-style parm declarations. */
6157 register tree parmdecls = getdecls ();
6159 /* This is a chain of any other decls that came in among the parm
6160 declarations. If a parm is declared with enum {foo, bar} x;
6161 then CONST_DECLs for foo and bar are put here. */
6162 tree nonparms = 0;
6164 /* Nonzero if this definition is written with a prototype. */
6165 int prototype = 0;
6167 /* The function containing FNDECL, if any. */
6168 tree context = decl_function_context (fndecl);
6170 if (specparms != 0 && TREE_CODE (specparms) != TREE_LIST)
6172 /* This case is when the function was defined with an ANSI prototype.
6173 The parms already have decls, so we need not do anything here
6174 except record them as in effect
6175 and complain if any redundant old-style parm decls were written. */
6177 register tree next;
6178 tree others = 0;
6180 prototype = 1;
6182 if (parmdecls != 0)
6184 tree decl, link;
6186 error_with_decl (fndecl,
6187 "parm types given both in parmlist and separately");
6188 /* Get rid of the erroneous decls; don't keep them on
6189 the list of parms, since they might not be PARM_DECLs. */
6190 for (decl = current_binding_level->names;
6191 decl; decl = TREE_CHAIN (decl))
6192 if (DECL_NAME (decl))
6193 IDENTIFIER_LOCAL_VALUE (DECL_NAME (decl)) = 0;
6194 for (link = current_binding_level->shadowed;
6195 link; link = TREE_CHAIN (link))
6196 IDENTIFIER_LOCAL_VALUE (TREE_PURPOSE (link)) = TREE_VALUE (link);
6197 current_binding_level->names = 0;
6198 current_binding_level->shadowed = 0;
6201 specparms = nreverse (specparms);
6202 for (parm = specparms; parm; parm = next)
6204 next = TREE_CHAIN (parm);
6205 if (TREE_CODE (parm) == PARM_DECL)
6207 if (DECL_NAME (parm) == 0)
6208 error_with_decl (parm, "parameter name omitted");
6209 else if (TREE_CODE (TREE_TYPE (parm)) != ERROR_MARK
6210 && VOID_TYPE_P (TREE_TYPE (parm)))
6212 error_with_decl (parm, "parameter `%s' declared void");
6213 /* Change the type to error_mark_node so this parameter
6214 will be ignored by assign_parms. */
6215 TREE_TYPE (parm) = error_mark_node;
6217 pushdecl (parm);
6219 else
6221 /* If we find an enum constant or a type tag,
6222 put it aside for the moment. */
6223 TREE_CHAIN (parm) = 0;
6224 others = chainon (others, parm);
6228 /* Get the decls in their original chain order
6229 and record in the function. */
6230 DECL_ARGUMENTS (fndecl) = getdecls ();
6232 #if 0
6233 /* If this function takes a variable number of arguments,
6234 add a phony parameter to the end of the parm list,
6235 to represent the position of the first unnamed argument. */
6236 if (TREE_VALUE (tree_last (TYPE_ARG_TYPES (TREE_TYPE (fndecl))))
6237 != void_type_node)
6239 tree dummy = build_decl (PARM_DECL, NULL_TREE, void_type_node);
6240 /* Let's hope the address of the unnamed parm
6241 won't depend on its type. */
6242 TREE_TYPE (dummy) = integer_type_node;
6243 DECL_ARG_TYPE (dummy) = integer_type_node;
6244 DECL_ARGUMENTS (fndecl) = chainon (DECL_ARGUMENTS (fndecl), dummy);
6246 #endif
6248 /* Now pushdecl the enum constants. */
6249 for (parm = others; parm; parm = next)
6251 next = TREE_CHAIN (parm);
6252 if (DECL_NAME (parm) == 0)
6254 else if (TYPE_MAIN_VARIANT (TREE_TYPE (parm)) == void_type_node)
6256 else if (TREE_CODE (parm) != PARM_DECL)
6257 pushdecl (parm);
6260 storetags (chainon (parmtags, gettags ()));
6262 else
6264 /* SPECPARMS is an identifier list--a chain of TREE_LIST nodes
6265 each with a parm name as the TREE_VALUE.
6267 PARMDECLS is a chain of declarations for parameters.
6268 Warning! It can also contain CONST_DECLs which are not parameters
6269 but are names of enumerators of any enum types
6270 declared among the parameters.
6272 First match each formal parameter name with its declaration.
6273 Associate decls with the names and store the decls
6274 into the TREE_PURPOSE slots. */
6276 /* We use DECL_WEAK as a flag to show which parameters have been
6277 seen already since it is not used on PARM_DECL or CONST_DECL. */
6278 for (parm = parmdecls; parm; parm = TREE_CHAIN (parm))
6279 DECL_WEAK (parm) = 0;
6281 for (parm = specparms; parm; parm = TREE_CHAIN (parm))
6283 register tree tail, found = NULL;
6285 if (TREE_VALUE (parm) == 0)
6287 error_with_decl (fndecl,
6288 "parameter name missing from parameter list");
6289 TREE_PURPOSE (parm) = 0;
6290 continue;
6293 /* See if any of the parmdecls specifies this parm by name.
6294 Ignore any enumerator decls. */
6295 for (tail = parmdecls; tail; tail = TREE_CHAIN (tail))
6296 if (DECL_NAME (tail) == TREE_VALUE (parm)
6297 && TREE_CODE (tail) == PARM_DECL)
6299 found = tail;
6300 break;
6303 /* If declaration already marked, we have a duplicate name.
6304 Complain, and don't use this decl twice. */
6305 if (found && DECL_WEAK (found))
6307 error_with_decl (found, "multiple parameters named `%s'");
6308 found = 0;
6311 /* If the declaration says "void", complain and ignore it. */
6312 if (found && VOID_TYPE_P (TREE_TYPE (found)))
6314 error_with_decl (found, "parameter `%s' declared void");
6315 TREE_TYPE (found) = integer_type_node;
6316 DECL_ARG_TYPE (found) = integer_type_node;
6317 layout_decl (found, 0);
6320 /* Traditionally, a parm declared float is actually a double. */
6321 if (found && flag_traditional
6322 && TYPE_MAIN_VARIANT (TREE_TYPE (found)) == float_type_node)
6324 TREE_TYPE (found) = double_type_node;
6325 DECL_ARG_TYPE (found) = double_type_node;
6326 layout_decl (found, 0);
6329 /* If no declaration found, default to int. */
6330 if (!found)
6332 found = build_decl (PARM_DECL, TREE_VALUE (parm),
6333 integer_type_node);
6334 DECL_ARG_TYPE (found) = TREE_TYPE (found);
6335 DECL_SOURCE_LINE (found) = DECL_SOURCE_LINE (fndecl);
6336 DECL_SOURCE_FILE (found) = DECL_SOURCE_FILE (fndecl);
6337 if (flag_isoc99)
6338 pedwarn_with_decl (found, "type of `%s' defaults to `int'");
6339 else if (extra_warnings)
6340 warning_with_decl (found, "type of `%s' defaults to `int'");
6341 pushdecl (found);
6344 TREE_PURPOSE (parm) = found;
6346 /* Mark this decl as "already found". */
6347 DECL_WEAK (found) = 1;
6350 /* Put anything which is on the parmdecls chain and which is
6351 not a PARM_DECL onto the list NONPARMS. (The types of
6352 non-parm things which might appear on the list include
6353 enumerators and NULL-named TYPE_DECL nodes.) Complain about
6354 any actual PARM_DECLs not matched with any names. */
6356 nonparms = 0;
6357 for (parm = parmdecls; parm;)
6359 tree next = TREE_CHAIN (parm);
6360 TREE_CHAIN (parm) = 0;
6362 if (TREE_CODE (parm) != PARM_DECL)
6363 nonparms = chainon (nonparms, parm);
6364 else
6366 /* Complain about args with incomplete types. */
6367 if (!COMPLETE_TYPE_P (TREE_TYPE (parm)))
6369 error_with_decl (parm, "parameter `%s' has incomplete type");
6370 TREE_TYPE (parm) = error_mark_node;
6373 if (! DECL_WEAK (parm))
6375 error_with_decl (parm,
6376 "declaration for parameter `%s' but no such parameter");
6377 /* Pretend the parameter was not missing.
6378 This gets us to a standard state and minimizes
6379 further error messages. */
6380 specparms
6381 = chainon (specparms,
6382 tree_cons (parm, NULL_TREE, NULL_TREE));
6386 parm = next;
6389 /* Chain the declarations together in the order of the list of
6390 names. Store that chain in the function decl, replacing the
6391 list of names. */
6392 parm = specparms;
6393 DECL_ARGUMENTS (fndecl) = 0;
6395 register tree last;
6396 for (last = 0; parm; parm = TREE_CHAIN (parm))
6397 if (TREE_PURPOSE (parm))
6399 if (last == 0)
6400 DECL_ARGUMENTS (fndecl) = TREE_PURPOSE (parm);
6401 else
6402 TREE_CHAIN (last) = TREE_PURPOSE (parm);
6403 last = TREE_PURPOSE (parm);
6404 TREE_CHAIN (last) = 0;
6408 /* If there was a previous prototype,
6409 set the DECL_ARG_TYPE of each argument according to
6410 the type previously specified, and report any mismatches. */
6412 if (TYPE_ARG_TYPES (TREE_TYPE (fndecl)))
6414 register tree type;
6415 for (parm = DECL_ARGUMENTS (fndecl),
6416 type = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
6417 parm || (type && (TYPE_MAIN_VARIANT (TREE_VALUE (type))
6418 != void_type_node));
6419 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
6421 if (parm == 0 || type == 0
6422 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
6424 error ("number of arguments doesn't match prototype");
6425 error_with_file_and_line (current_function_prototype_file,
6426 current_function_prototype_line,
6427 "prototype declaration");
6428 break;
6430 /* Type for passing arg must be consistent with that
6431 declared for the arg. ISO C says we take the unqualified
6432 type for parameters declared with qualified type. */
6433 if (! comptypes (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (parm)),
6434 TYPE_MAIN_VARIANT (TREE_VALUE (type))))
6436 if (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
6437 == TYPE_MAIN_VARIANT (TREE_VALUE (type)))
6439 /* Adjust argument to match prototype. E.g. a previous
6440 `int foo(float);' prototype causes
6441 `int foo(x) float x; {...}' to be treated like
6442 `int foo(float x) {...}'. This is particularly
6443 useful for argument types like uid_t. */
6444 DECL_ARG_TYPE (parm) = TREE_TYPE (parm);
6446 if (PROMOTE_PROTOTYPES
6447 && INTEGRAL_TYPE_P (TREE_TYPE (parm))
6448 && TYPE_PRECISION (TREE_TYPE (parm))
6449 < TYPE_PRECISION (integer_type_node))
6450 DECL_ARG_TYPE (parm) = integer_type_node;
6452 if (pedantic)
6454 pedwarn ("promoted argument `%s' doesn't match prototype",
6455 IDENTIFIER_POINTER (DECL_NAME (parm)));
6456 warning_with_file_and_line
6457 (current_function_prototype_file,
6458 current_function_prototype_line,
6459 "prototype declaration");
6462 /* If -traditional, allow `int' argument to match
6463 `unsigned' prototype. */
6464 else if (! (flag_traditional
6465 && TYPE_MAIN_VARIANT (TREE_TYPE (parm)) == integer_type_node
6466 && TYPE_MAIN_VARIANT (TREE_VALUE (type)) == unsigned_type_node))
6468 error ("argument `%s' doesn't match prototype",
6469 IDENTIFIER_POINTER (DECL_NAME (parm)));
6470 error_with_file_and_line (current_function_prototype_file,
6471 current_function_prototype_line,
6472 "prototype declaration");
6476 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = 0;
6479 /* Otherwise, create a prototype that would match. */
6481 else
6483 tree actual = 0, last = 0, type;
6485 for (parm = DECL_ARGUMENTS (fndecl); parm; parm = TREE_CHAIN (parm))
6487 type = tree_cons (NULL_TREE, DECL_ARG_TYPE (parm), NULL_TREE);
6488 if (last)
6489 TREE_CHAIN (last) = type;
6490 else
6491 actual = type;
6492 last = type;
6494 type = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
6495 if (last)
6496 TREE_CHAIN (last) = type;
6497 else
6498 actual = type;
6500 /* We are going to assign a new value for the TYPE_ACTUAL_ARG_TYPES
6501 of the type of this function, but we need to avoid having this
6502 affect the types of other similarly-typed functions, so we must
6503 first force the generation of an identical (but separate) type
6504 node for the relevant function type. The new node we create
6505 will be a variant of the main variant of the original function
6506 type. */
6508 TREE_TYPE (fndecl) = build_type_copy (TREE_TYPE (fndecl));
6510 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = actual;
6513 /* Now store the final chain of decls for the arguments
6514 as the decl-chain of the current lexical scope.
6515 Put the enumerators in as well, at the front so that
6516 DECL_ARGUMENTS is not modified. */
6518 storedecls (chainon (nonparms, DECL_ARGUMENTS (fndecl)));
6521 /* Make sure the binding level for the top of the function body
6522 gets a BLOCK if there are any in the function.
6523 Otherwise, the dbx output is wrong. */
6525 keep_next_if_subblocks = 1;
6527 /* ??? This might be an improvement,
6528 but needs to be thought about some more. */
6529 #if 0
6530 keep_next_level_flag = 1;
6531 #endif
6533 /* Write a record describing this function definition to the prototypes
6534 file (if requested). */
6536 gen_aux_info_record (fndecl, 1, 0, prototype);
6538 /* Initialize the RTL code for the function. */
6539 init_function_start (fndecl, input_filename, lineno);
6541 /* Begin the statement tree for this function. */
6542 DECL_LANG_SPECIFIC (current_function_decl)
6543 =((struct lang_decl *) ggc_alloc_cleared (sizeof (struct lang_decl)));
6544 begin_stmt_tree (&DECL_SAVED_TREE (current_function_decl));
6546 /* If this is a nested function, save away the sizes of any
6547 variable-size types so that we can expand them when generating
6548 RTL. */
6549 if (context)
6551 tree t;
6553 DECL_LANG_SPECIFIC (fndecl)->pending_sizes
6554 = nreverse (get_pending_sizes ());
6555 for (t = DECL_LANG_SPECIFIC (fndecl)->pending_sizes;
6557 t = TREE_CHAIN (t))
6558 SAVE_EXPR_CONTEXT (TREE_VALUE (t)) = context;
6561 /* This function is being processed in whole-function mode. */
6562 cfun->x_whole_function_mode_p = 1;
6564 /* Even though we're inside a function body, we still don't want to
6565 call expand_expr to calculate the size of a variable-sized array.
6566 We haven't necessarily assigned RTL to all variables yet, so it's
6567 not safe to try to expand expressions involving them. */
6568 immediate_size_expand = 0;
6569 cfun->x_dont_save_pending_sizes_p = 1;
6572 /* Finish up a function declaration and compile that function
6573 all the way to assembler language output. The free the storage
6574 for the function definition.
6576 This is called after parsing the body of the function definition.
6578 NESTED is nonzero if the function being finished is nested in another. */
6580 void
6581 finish_function (nested)
6582 int nested;
6584 register tree fndecl = current_function_decl;
6586 /* TREE_READONLY (fndecl) = 1;
6587 This caused &foo to be of type ptr-to-const-function
6588 which then got a warning when stored in a ptr-to-function variable. */
6590 poplevel (1, 0, 1);
6591 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
6593 /* Must mark the RESULT_DECL as being in this function. */
6595 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
6597 /* Obey `register' declarations if `setjmp' is called in this fn. */
6598 if (flag_traditional && current_function_calls_setjmp)
6600 setjmp_protect (DECL_INITIAL (fndecl));
6601 setjmp_protect_args ();
6604 if (MAIN_NAME_P (DECL_NAME (fndecl)) && flag_hosted)
6606 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (fndecl)))
6607 != integer_type_node)
6609 /* If warn_main is 1 (-Wmain) or 2 (-Wall), we have already warned.
6610 If warn_main is -1 (-Wno-main) we don't want to be warned. */
6611 if (! warn_main)
6612 pedwarn_with_decl (fndecl, "return type of `%s' is not `int'");
6614 else
6616 #ifdef DEFAULT_MAIN_RETURN
6617 /* Make it so that `main' always returns success by default. */
6618 DEFAULT_MAIN_RETURN;
6619 #else
6620 if (flag_isoc99)
6621 c_expand_return (integer_zero_node);
6622 #endif
6626 finish_fname_decls ();
6628 /* Tie off the statement tree for this function. */
6629 finish_stmt_tree (&DECL_SAVED_TREE (fndecl));
6630 /* Clear out memory we no longer need. */
6631 free_after_parsing (cfun);
6632 /* Since we never call rest_of_compilation, we never clear
6633 CFUN. Do so explicitly. */
6634 free_after_compilation (cfun);
6635 cfun = NULL;
6637 if (! nested)
6639 /* Generate RTL for the body of this function. */
6640 c_expand_body (fndecl, nested);
6641 /* Let the error reporting routines know that we're outside a
6642 function. For a nested function, this value is used in
6643 pop_c_function_context and then reset via pop_function_context. */
6644 current_function_decl = NULL;
6648 /* Generate the RTL for the body of FNDECL. If NESTED_P is non-zero,
6649 then we are already in the process of generating RTL for another
6650 function. */
6652 static void
6653 c_expand_body (fndecl, nested_p)
6654 tree fndecl;
6655 int nested_p;
6657 /* There's no reason to do any of the work here if we're only doing
6658 semantic analysis; this code just generates RTL. */
6659 if (flag_syntax_only)
6660 return;
6662 if (nested_p)
6664 /* Make sure that we will evaluate variable-sized types involved
6665 in our function's type. */
6666 expand_pending_sizes (DECL_LANG_SPECIFIC (fndecl)->pending_sizes);
6667 /* Squirrel away our current state. */
6668 push_function_context ();
6671 /* Initialize the RTL code for the function. */
6672 current_function_decl = fndecl;
6673 init_function_start (fndecl, input_filename, DECL_SOURCE_LINE (fndecl));
6675 /* This function is being processed in whole-function mode. */
6676 cfun->x_whole_function_mode_p = 1;
6678 /* Even though we're inside a function body, we still don't want to
6679 call expand_expr to calculate the size of a variable-sized array.
6680 We haven't necessarily assigned RTL to all variables yet, so it's
6681 not safe to try to expand expressions involving them. */
6682 immediate_size_expand = 0;
6683 cfun->x_dont_save_pending_sizes_p = 1;
6685 /* If this is a varargs function, inform function.c. */
6686 if (c_function_varargs)
6687 mark_varargs ();
6689 /* Set up parameters and prepare for return, for the function. */
6690 expand_function_start (fndecl, 0);
6692 /* If this function is `main', emit a call to `__main'
6693 to run global initializers, etc. */
6694 if (DECL_NAME (fndecl)
6695 && MAIN_NAME_P (DECL_NAME (fndecl))
6696 && DECL_CONTEXT (fndecl) == NULL_TREE)
6697 expand_main_function ();
6699 /* Generate the RTL for this function. */
6700 expand_stmt (DECL_SAVED_TREE (fndecl));
6701 /* Allow the body of the function to be garbage collected. */
6702 DECL_SAVED_TREE (fndecl) = NULL_TREE;
6704 /* We hard-wired immediate_size_expand to zero above.
6705 expand_function_end will decrement this variable. So, we set the
6706 variable to one here, so that after the decrement it will remain
6707 zero. */
6708 immediate_size_expand = 1;
6710 /* Allow language dialects to perform special processing. */
6711 if (lang_expand_function_end)
6712 (*lang_expand_function_end) ();
6714 /* Generate rtl for function exit. */
6715 expand_function_end (input_filename, lineno, 0);
6717 /* If this is a nested function, protect the local variables in the stack
6718 above us from being collected while we're compiling this function. */
6719 if (nested_p)
6720 ggc_push_context ();
6722 /* Run the optimizers and output the assembler code for this function. */
6723 rest_of_compilation (fndecl);
6725 /* Undo the GC context switch. */
6726 if (nested_p)
6727 ggc_pop_context ();
6729 /* With just -W, complain only if function returns both with
6730 and without a value. */
6731 if (extra_warnings
6732 && current_function_returns_value
6733 && current_function_returns_null)
6734 warning ("this function may return with or without a value");
6736 /* If requested, warn about function definitions where the function will
6737 return a value (usually of some struct or union type) which itself will
6738 take up a lot of stack space. */
6740 if (warn_larger_than && !DECL_EXTERNAL (fndecl) && TREE_TYPE (fndecl))
6742 tree ret_type = TREE_TYPE (TREE_TYPE (fndecl));
6744 if (ret_type && TYPE_SIZE_UNIT (ret_type)
6745 && TREE_CODE (TYPE_SIZE_UNIT (ret_type)) == INTEGER_CST
6746 && 0 < compare_tree_int (TYPE_SIZE_UNIT (ret_type),
6747 larger_than_size))
6749 unsigned int size_as_int
6750 = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (ret_type));
6752 if (compare_tree_int (TYPE_SIZE_UNIT (ret_type), size_as_int) == 0)
6753 warning_with_decl (fndecl,
6754 "size of return value of `%s' is %u bytes",
6755 size_as_int);
6756 else
6757 warning_with_decl (fndecl,
6758 "size of return value of `%s' is larger than %d bytes",
6759 larger_than_size);
6763 if (DECL_SAVED_INSNS (fndecl) == 0 && ! nested_p)
6765 /* Stop pointing to the local nodes about to be freed.
6766 But DECL_INITIAL must remain nonzero so we know this
6767 was an actual function definition.
6768 For a nested function, this is done in pop_c_function_context.
6769 If rest_of_compilation set this to 0, leave it 0. */
6770 if (DECL_INITIAL (fndecl) != 0)
6771 DECL_INITIAL (fndecl) = error_mark_node;
6773 DECL_ARGUMENTS (fndecl) = 0;
6776 if (DECL_STATIC_CONSTRUCTOR (fndecl))
6778 #ifndef ASM_OUTPUT_CONSTRUCTOR
6779 if (! flag_gnu_linker)
6780 static_ctors = tree_cons (NULL_TREE, fndecl, static_ctors);
6781 else
6782 #endif
6783 assemble_constructor (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (fndecl)));
6786 if (DECL_STATIC_DESTRUCTOR (fndecl))
6788 #ifndef ASM_OUTPUT_DESTRUCTOR
6789 if (! flag_gnu_linker)
6790 static_dtors = tree_cons (NULL_TREE, fndecl, static_dtors);
6791 else
6792 #endif
6793 assemble_destructor (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (fndecl)));
6796 if (nested_p)
6797 /* Return to the enclosing function. */
6798 pop_function_context ();
6801 /* Check the declarations given in a for-loop for satisfying the C99
6802 constraints. */
6803 void
6804 check_for_loop_decls ()
6806 tree t;
6808 if (!flag_isoc99)
6810 /* If we get here, declarations have been used in a for loop without
6811 the C99 for loop scope. This doesn't make much sense, so don't
6812 allow it. */
6813 error ("`for' loop initial declaration used outside C99 mode");
6814 return;
6816 /* C99 subclause 6.8.5 paragraph 3:
6818 [#3] The declaration part of a for statement shall only
6819 declare identifiers for objects having storage class auto or
6820 register.
6822 It isn't clear whether, in this sentence, "identifiers" binds to
6823 "shall only declare" or to "objects" - that is, whether all identifiers
6824 declared must be identifiers for objects, or whether the restriction
6825 only applies to those that are. (A question on this in comp.std.c
6826 in November 2000 received no answer.) We implement the strictest
6827 interpretation, to avoid creating an extension which later causes
6828 problems. */
6830 for (t = gettags (); t; t = TREE_CHAIN (t))
6832 if (TREE_PURPOSE (t) != 0)
6833 error ("`%s %s' declared in `for' loop initial declaration",
6834 (TREE_CODE (TREE_VALUE (t)) == RECORD_TYPE ? "struct"
6835 : TREE_CODE (TREE_VALUE (t)) == UNION_TYPE ? "union"
6836 : "enum"),
6837 IDENTIFIER_POINTER (TREE_PURPOSE (t)));
6839 for (t = getdecls (); t; t = TREE_CHAIN (t))
6841 if (TREE_CODE (t) != VAR_DECL && DECL_NAME (t))
6842 error_with_decl (t, "declaration of non-variable `%s' in `for' loop initial declaration");
6843 else if (TREE_STATIC (t))
6844 error_with_decl (t, "declaration of static variable `%s' in `for' loop initial declaration");
6845 else if (DECL_EXTERNAL (t))
6846 error_with_decl (t, "declaration of `extern' variable `%s' in `for' loop initial declaration");
6850 /* Save and restore the variables in this file and elsewhere
6851 that keep track of the progress of compilation of the current function.
6852 Used for nested functions. */
6854 struct c_language_function
6856 struct language_function base;
6857 tree named_labels;
6858 tree shadowed_labels;
6859 int returns_value;
6860 int returns_null;
6861 int warn_about_return_type;
6862 int extern_inline;
6863 struct binding_level *binding_level;
6866 /* Save and reinitialize the variables
6867 used during compilation of a C function. */
6869 void
6870 push_c_function_context (f)
6871 struct function *f;
6873 struct c_language_function *p;
6874 p = ((struct c_language_function *)
6875 xmalloc (sizeof (struct c_language_function)));
6876 f->language = (struct language_function *) p;
6878 p->base.x_stmt_tree = c_stmt_tree;
6879 p->base.x_scope_stmt_stack = c_scope_stmt_stack;
6880 p->named_labels = named_labels;
6881 p->shadowed_labels = shadowed_labels;
6882 p->returns_value = current_function_returns_value;
6883 p->returns_null = current_function_returns_null;
6884 p->warn_about_return_type = warn_about_return_type;
6885 p->extern_inline = current_extern_inline;
6886 p->binding_level = current_binding_level;
6889 /* Restore the variables used during compilation of a C function. */
6891 void
6892 pop_c_function_context (f)
6893 struct function *f;
6895 struct c_language_function *p
6896 = (struct c_language_function *) f->language;
6897 tree link;
6899 /* Bring back all the labels that were shadowed. */
6900 for (link = shadowed_labels; link; link = TREE_CHAIN (link))
6901 if (DECL_NAME (TREE_VALUE (link)) != 0)
6902 IDENTIFIER_LABEL_VALUE (DECL_NAME (TREE_VALUE (link)))
6903 = TREE_VALUE (link);
6905 if (DECL_SAVED_INSNS (current_function_decl) == 0
6906 && DECL_SAVED_TREE (current_function_decl) == NULL_TREE)
6908 /* Stop pointing to the local nodes about to be freed. */
6909 /* But DECL_INITIAL must remain nonzero so we know this
6910 was an actual function definition. */
6911 DECL_INITIAL (current_function_decl) = error_mark_node;
6912 DECL_ARGUMENTS (current_function_decl) = 0;
6915 c_stmt_tree = p->base.x_stmt_tree;
6916 c_scope_stmt_stack = p->base.x_scope_stmt_stack;
6917 named_labels = p->named_labels;
6918 shadowed_labels = p->shadowed_labels;
6919 current_function_returns_value = p->returns_value;
6920 current_function_returns_null = p->returns_null;
6921 warn_about_return_type = p->warn_about_return_type;
6922 current_extern_inline = p->extern_inline;
6923 current_binding_level = p->binding_level;
6925 free (p);
6926 f->language = 0;
6929 /* Mark the language specific parts of F for GC. */
6931 void
6932 mark_c_function_context (f)
6933 struct function *f;
6935 struct c_language_function *p
6936 = (struct c_language_function *) f->language;
6938 if (p == 0)
6939 return;
6941 mark_c_language_function (&p->base);
6942 ggc_mark_tree (p->shadowed_labels);
6943 ggc_mark_tree (p->named_labels);
6944 mark_binding_level (&p->binding_level);
6947 /* Copy the DECL_LANG_SEPECIFIC data associated with NODE. */
6949 void
6950 copy_lang_decl (decl)
6951 tree decl;
6953 struct lang_decl *ld;
6955 if (!DECL_LANG_SPECIFIC (decl))
6956 return;
6958 ld = (struct lang_decl *) ggc_alloc (sizeof (struct lang_decl));
6959 memcpy ((char *) ld, (char *) DECL_LANG_SPECIFIC (decl),
6960 sizeof (struct lang_decl));
6961 DECL_LANG_SPECIFIC (decl) = ld;
6964 /* Mark the language specific bits in T for GC. */
6966 void
6967 lang_mark_tree (t)
6968 tree t;
6970 if (TREE_CODE (t) == IDENTIFIER_NODE)
6972 struct lang_identifier *i = (struct lang_identifier *) t;
6973 ggc_mark_tree (i->global_value);
6974 ggc_mark_tree (i->local_value);
6975 ggc_mark_tree (i->label_value);
6976 ggc_mark_tree (i->implicit_decl);
6977 ggc_mark_tree (i->error_locus);
6978 ggc_mark_tree (i->limbo_value);
6980 else if (TYPE_P (t) && TYPE_LANG_SPECIFIC (t))
6981 ggc_mark (TYPE_LANG_SPECIFIC (t));
6982 else if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
6984 ggc_mark (DECL_LANG_SPECIFIC (t));
6985 c_mark_lang_decl (&DECL_LANG_SPECIFIC (t)->base);
6986 ggc_mark_tree (DECL_LANG_SPECIFIC (t)->pending_sizes);
6990 /* The functions below are required for functionality of doing
6991 function at once processing in the C front end. Currently these
6992 functions are not called from anywhere in the C front end, but as
6993 these changes continue, that will change. */
6995 /* Returns non-zero if the current statement is a full expression,
6996 i.e. temporaries created during that statement should be destroyed
6997 at the end of the statement. */
7000 stmts_are_full_exprs_p ()
7002 return 0;
7005 /* Returns the stmt_tree (if any) to which statements are currently
7006 being added. If there is no active statement-tree, NULL is
7007 returned. */
7009 stmt_tree
7010 current_stmt_tree ()
7012 return &c_stmt_tree;
7015 /* Returns the stack of SCOPE_STMTs for the current function. */
7017 tree *
7018 current_scope_stmt_stack ()
7020 return &c_scope_stmt_stack;
7023 /* Nonzero if TYPE is an anonymous union or struct type. Always 0 in
7024 C. */
7027 anon_aggr_type_p (node)
7028 tree node ATTRIBUTE_UNUSED;
7030 return 0;
7033 /* Dummy function in place of callback used by C++. */
7035 void
7036 extract_interface_info ()
7040 /* Return a new COMPOUND_STMT, after adding it to the current
7041 statement tree. */
7043 tree
7044 c_begin_compound_stmt ()
7046 tree stmt;
7048 /* Create the COMPOUND_STMT. */
7049 stmt = add_stmt (build_stmt (COMPOUND_STMT, NULL_TREE));
7051 return stmt;
7054 /* Expand T (a DECL_STMT) if it declares an entity not handled by the
7055 common code. */
7057 void
7058 c_expand_decl_stmt (t)
7059 tree t;
7061 tree decl = DECL_STMT_DECL (t);
7063 /* Expand nested functions. */
7064 if (TREE_CODE (decl) == FUNCTION_DECL
7065 && DECL_CONTEXT (decl) == current_function_decl
7066 && DECL_SAVED_TREE (decl))
7067 c_expand_body (decl, /*nested_p=*/1);
7070 /* Return the IDENTIFIER_GLOBAL_VALUE of T, for use in common code, since
7071 the definition of IDENTIFIER_GLOBAL_VALUE is different for C and C++. */
7073 tree
7074 identifier_global_value (t)
7075 tree t;
7077 return IDENTIFIER_GLOBAL_VALUE (t);
7080 /* Record a builtin type for C. If NAME is non-NULL, it is the name used;
7081 otherwise the name is found in ridpointers from RID_INDEX. */
7083 void
7084 record_builtin_type (rid_index, name, type)
7085 enum rid rid_index;
7086 const char *name;
7087 tree type;
7089 tree id;
7090 if (name == 0)
7091 id = ridpointers[(int) rid_index];
7092 else
7093 id = get_identifier (name);
7094 pushdecl (build_decl (TYPE_DECL, id, type));
7097 /* Build the void_list_node (void_type_node having been created). */
7098 tree
7099 build_void_list_node ()
7101 tree t = build_tree_list (NULL_TREE, void_type_node);
7102 return t;