1 /* Process declarations and variables for C compiler.
2 Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
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. */
31 #include "coretypes.h"
36 #include "tree-inline.h"
53 #include "langhooks.h"
54 #include "tree-mudflap.h"
55 #include "tree-gimple.h"
56 #include "diagnostic.h"
57 #include "tree-dump.h"
62 #include "langhooks-def.h"
63 #include "pointer-set.h"
65 /* In grokdeclarator, distinguish syntactic contexts of declarators. */
67 { NORMAL, /* Ordinary declaration */
68 FUNCDEF, /* Function definition */
69 PARM, /* Declaration of parm before function body */
70 FIELD, /* Declaration inside struct or union */
71 TYPENAME}; /* Typename (inside cast or sizeof) */
74 /* Nonzero if we have seen an invalid cross reference
75 to a struct, union, or enum, but not yet printed the message. */
76 tree pending_invalid_xref;
78 /* File and line to appear in the eventual error message. */
79 location_t pending_invalid_xref_location;
81 /* True means we've initialized exception handling. */
82 bool c_eh_initialized_p;
84 /* While defining an enum type, this is 1 plus the last enumerator
85 constant value. Note that will do not have to save this or `enum_overflow'
86 around nested function definition since such a definition could only
87 occur in an enum value expression and we don't use these variables in
90 static tree enum_next_value;
92 /* Nonzero means that there was overflow computing enum_next_value. */
94 static int enum_overflow;
96 /* The file and line that the prototype came from if this is an
97 old-style definition; used for diagnostics in
98 store_parm_decls_oldstyle. */
100 static location_t current_function_prototype_locus;
102 /* Whether this prototype was built-in. */
104 static bool current_function_prototype_built_in;
106 /* The argument type information of this prototype. */
108 static tree current_function_prototype_arg_types;
110 /* The argument information structure for the function currently being
113 static struct c_arg_info *current_function_arg_info;
115 /* The obstack on which parser and related data structures, which are
116 not live beyond their top-level declaration or definition, are
118 struct obstack parser_obstack;
120 /* The current statement tree. */
122 static GTY(()) struct stmt_tree_s c_stmt_tree;
124 /* State saving variables. */
128 /* Linked list of TRANSLATION_UNIT_DECLS for the translation units
129 included in this invocation. Note that the current translation
130 unit is not included in this list. */
132 static GTY(()) tree all_translation_units;
134 /* A list of decls to be made automatically visible in each file scope. */
135 static GTY(()) tree visible_builtins;
137 /* Set to 0 at beginning of a function definition, set to 1 if
138 a return statement that specifies a return value is seen. */
140 int current_function_returns_value;
142 /* Set to 0 at beginning of a function definition, set to 1 if
143 a return statement with no argument is seen. */
145 int current_function_returns_null;
147 /* Set to 0 at beginning of a function definition, set to 1 if
148 a call to a noreturn function is seen. */
150 int current_function_returns_abnormally;
152 /* Set to nonzero by `grokdeclarator' for a function
153 whose return type is defaulted, if warnings for this are desired. */
155 static int warn_about_return_type;
157 /* Nonzero when starting a function declared `extern inline'. */
159 static int current_extern_inline;
161 /* Nonzero when the current toplevel function contains a declaration
162 of a nested function which is never defined. */
164 static bool undef_nested_function;
166 /* True means global_bindings_p should return false even if the scope stack
167 says we are in file scope. */
168 bool c_override_global_bindings_to_false;
171 /* Each c_binding structure describes one binding of an identifier to
172 a decl. All the decls in a scope - irrespective of namespace - are
173 chained together by the ->prev field, which (as the name implies)
174 runs in reverse order. All the decls in a given namespace bound to
175 a given identifier are chained by the ->shadowed field, which runs
176 from inner to outer scopes.
178 The ->decl field usually points to a DECL node, but there are two
179 exceptions. In the namespace of type tags, the bound entity is a
180 RECORD_TYPE, UNION_TYPE, or ENUMERAL_TYPE node. If an undeclared
181 identifier is encountered, it is bound to error_mark_node to
182 suppress further errors about that identifier in the current
185 The ->type field stores the type of the declaration in this scope;
186 if NULL, the type is the type of the ->decl field. This is only of
187 relevance for objects with external or internal linkage which may
188 be redeclared in inner scopes, forming composite types that only
189 persist for the duration of those scopes. In the external scope,
190 this stores the composite of all the types declared for this
191 object, visible or not. The ->inner_comp field (used only at file
192 scope) stores whether an incomplete array type at file scope was
193 completed at an inner scope to an array size other than 1.
195 The depth field is copied from the scope structure that holds this
196 decl. It is used to preserve the proper ordering of the ->shadowed
197 field (see bind()) and also for a handful of special-case checks.
198 Finally, the invisible bit is true for a decl which should be
199 ignored for purposes of normal name lookup, and the nested bit is
200 true for a decl that's been bound a second time in an inner scope;
201 in all such cases, the binding in the outer scope will have its
202 invisible bit true. */
204 struct c_binding GTY((chain_next ("%h.prev")))
206 tree decl; /* the decl bound */
207 tree type; /* the type in this scope */
208 tree id; /* the identifier it's bound to */
209 struct c_binding *prev; /* the previous decl in this scope */
210 struct c_binding *shadowed; /* the innermost decl shadowed by this one */
211 unsigned int depth : 28; /* depth of this scope */
212 BOOL_BITFIELD invisible : 1; /* normal lookup should ignore this binding */
213 BOOL_BITFIELD nested : 1; /* do not set DECL_CONTEXT when popping */
214 BOOL_BITFIELD inner_comp : 1; /* incomplete array completed in inner scope */
217 #define B_IN_SCOPE(b1, b2) ((b1)->depth == (b2)->depth)
218 #define B_IN_CURRENT_SCOPE(b) ((b)->depth == current_scope->depth)
219 #define B_IN_FILE_SCOPE(b) ((b)->depth == 1 /*file_scope->depth*/)
220 #define B_IN_EXTERNAL_SCOPE(b) ((b)->depth == 0 /*external_scope->depth*/)
222 #define I_SYMBOL_BINDING(node) \
223 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->symbol_binding)
224 #define I_SYMBOL_DECL(node) \
225 (I_SYMBOL_BINDING(node) ? I_SYMBOL_BINDING(node)->decl : 0)
227 #define I_TAG_BINDING(node) \
228 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->tag_binding)
229 #define I_TAG_DECL(node) \
230 (I_TAG_BINDING(node) ? I_TAG_BINDING(node)->decl : 0)
232 #define I_LABEL_BINDING(node) \
233 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->label_binding)
234 #define I_LABEL_DECL(node) \
235 (I_LABEL_BINDING(node) ? I_LABEL_BINDING(node)->decl : 0)
237 /* Each C symbol points to three linked lists of c_binding structures.
238 These describe the values of the identifier in the three different
239 namespaces defined by the language. */
241 struct lang_identifier GTY(())
243 struct c_common_identifier common_id;
244 struct c_binding *symbol_binding; /* vars, funcs, constants, typedefs */
245 struct c_binding *tag_binding; /* struct/union/enum tags */
246 struct c_binding *label_binding; /* labels */
249 /* Validate c-lang.c's assumptions. */
250 extern char C_SIZEOF_STRUCT_LANG_IDENTIFIER_isnt_accurate
251 [(sizeof(struct lang_identifier) == C_SIZEOF_STRUCT_LANG_IDENTIFIER) ? 1 : -1];
253 /* The resulting tree type. */
256 GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE"),
257 chain_next ("TREE_CODE (&%h.generic) == INTEGER_TYPE ? (union lang_tree_node *) TYPE_NEXT_VARIANT (&%h.generic) : (union lang_tree_node *) TREE_CHAIN (&%h.generic)")))
259 union tree_node GTY ((tag ("0"),
260 desc ("tree_node_structure (&%h)")))
262 struct lang_identifier GTY ((tag ("1"))) identifier;
265 /* Each c_scope structure describes the complete contents of one
266 scope. Four scopes are distinguished specially: the innermost or
267 current scope, the innermost function scope, the file scope (always
268 the second to outermost) and the outermost or external scope.
270 Most declarations are recorded in the current scope.
272 All normal label declarations are recorded in the innermost
273 function scope, as are bindings of undeclared identifiers to
274 error_mark_node. (GCC permits nested functions as an extension,
275 hence the 'innermost' qualifier.) Explicitly declared labels
276 (using the __label__ extension) appear in the current scope.
278 Being in the file scope (current_scope == file_scope) causes
279 special behavior in several places below. Also, under some
280 conditions the Objective-C front end records declarations in the
281 file scope even though that isn't the current scope.
283 All declarations with external linkage are recorded in the external
284 scope, even if they aren't visible there; this models the fact that
285 such declarations are visible to the entire program, and (with a
286 bit of cleverness, see pushdecl) allows diagnosis of some violations
287 of C99 6.2.2p7 and 6.2.7p2:
289 If, within the same translation unit, the same identifier appears
290 with both internal and external linkage, the behavior is
293 All declarations that refer to the same object or function shall
294 have compatible type; otherwise, the behavior is undefined.
296 Initially only the built-in declarations, which describe compiler
297 intrinsic functions plus a subset of the standard library, are in
300 The order of the blocks list matters, and it is frequently appended
301 to. To avoid having to walk all the way to the end of the list on
302 each insertion, or reverse the list later, we maintain a pointer to
303 the last list entry. (FIXME: It should be feasible to use a reversed
306 The bindings list is strictly in reverse order of declarations;
307 pop_scope relies on this. */
310 struct c_scope GTY((chain_next ("%h.outer")))
312 /* The scope containing this one. */
313 struct c_scope *outer;
315 /* The next outermost function scope. */
316 struct c_scope *outer_function;
318 /* All bindings in this scope. */
319 struct c_binding *bindings;
321 /* For each scope (except the global one), a chain of BLOCK nodes
322 for all the scopes that were entered and exited one level down. */
326 /* The depth of this scope. Used to keep the ->shadowed chain of
327 bindings sorted innermost to outermost. */
328 unsigned int depth : 28;
330 /* True if we are currently filling this scope with parameter
332 BOOL_BITFIELD parm_flag : 1;
334 /* True if we already complained about forward parameter decls
335 in this scope. This prevents double warnings on
336 foo (int a; int b; ...) */
337 BOOL_BITFIELD warned_forward_parm_decls : 1;
339 /* True if this is the outermost block scope of a function body.
340 This scope contains the parameters, the local variables declared
341 in the outermost block, and all the labels (except those in
342 nested functions, or declared at block scope with __label__). */
343 BOOL_BITFIELD function_body : 1;
345 /* True means make a BLOCK for this scope no matter what. */
346 BOOL_BITFIELD keep : 1;
349 /* The scope currently in effect. */
351 static GTY(()) struct c_scope *current_scope;
353 /* The innermost function scope. Ordinary (not explicitly declared)
354 labels, bindings to error_mark_node, and the lazily-created
355 bindings of __func__ and its friends get this scope. */
357 static GTY(()) struct c_scope *current_function_scope;
359 /* The C file scope. This is reset for each input translation unit. */
361 static GTY(()) struct c_scope *file_scope;
363 /* The outermost scope. This is used for all declarations with
364 external linkage, and only these, hence the name. */
366 static GTY(()) struct c_scope *external_scope;
368 /* A chain of c_scope structures awaiting reuse. */
370 static GTY((deletable)) struct c_scope *scope_freelist;
372 /* A chain of c_binding structures awaiting reuse. */
374 static GTY((deletable)) struct c_binding *binding_freelist;
376 /* Append VAR to LIST in scope SCOPE. */
377 #define SCOPE_LIST_APPEND(scope, list, decl) do { \
378 struct c_scope *s_ = (scope); \
380 if (s_->list##_last) \
381 TREE_CHAIN (s_->list##_last) = d_; \
384 s_->list##_last = d_; \
387 /* Concatenate FROM in scope FSCOPE onto TO in scope TSCOPE. */
388 #define SCOPE_LIST_CONCAT(tscope, to, fscope, from) do { \
389 struct c_scope *t_ = (tscope); \
390 struct c_scope *f_ = (fscope); \
392 TREE_CHAIN (t_->to##_last) = f_->from; \
395 t_->to##_last = f_->from##_last; \
398 /* True means unconditionally make a BLOCK for the next scope pushed. */
400 static bool keep_next_level_flag;
402 /* True means the next call to push_scope will be the outermost scope
403 of a function body, so do not push a new scope, merely cease
404 expecting parameter decls. */
406 static bool next_is_function_body;
408 /* Functions called automatically at the beginning and end of execution. */
410 static GTY(()) tree static_ctors;
411 static GTY(()) tree static_dtors;
413 /* Forward declarations. */
414 static tree lookup_name_in_scope (tree, struct c_scope *);
415 static tree c_make_fname_decl (tree, int);
416 static tree grokdeclarator (const struct c_declarator *,
417 struct c_declspecs *,
418 enum decl_context, bool, tree *);
419 static tree grokparms (struct c_arg_info *, bool);
420 static void layout_array_type (tree);
422 /* T is a statement. Add it to the statement-tree. This is the
423 C/ObjC version--C++ has a slightly different version of this
429 enum tree_code code = TREE_CODE (t);
431 if (EXPR_P (t) && code != LABEL_EXPR)
433 if (!EXPR_HAS_LOCATION (t))
434 SET_EXPR_LOCATION (t, input_location);
437 if (code == LABEL_EXPR || code == CASE_LABEL_EXPR)
438 STATEMENT_LIST_HAS_LABEL (cur_stmt_list) = 1;
440 /* Add T to the statement-tree. Non-side-effect statements need to be
441 recorded during statement expressions. */
442 append_to_statement_list_force (t, &cur_stmt_list);
447 /* States indicating how grokdeclarator() should handle declspecs marked
448 with __attribute__((deprecated)). An object declared as
449 __attribute__((deprecated)) suppresses warnings of uses of other
452 enum deprecated_states {
457 static enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
460 c_print_identifier (FILE *file, tree node, int indent)
462 print_node (file, "symbol", I_SYMBOL_DECL (node), indent + 4);
463 print_node (file, "tag", I_TAG_DECL (node), indent + 4);
464 print_node (file, "label", I_LABEL_DECL (node), indent + 4);
465 if (C_IS_RESERVED_WORD (node))
467 tree rid = ridpointers[C_RID_CODE (node)];
468 indent_to (file, indent + 4);
469 fprintf (file, "rid " HOST_PTR_PRINTF " \"%s\"",
470 (void *) rid, IDENTIFIER_POINTER (rid));
474 /* Establish a binding between NAME, an IDENTIFIER_NODE, and DECL,
475 which may be any of several kinds of DECL or TYPE or error_mark_node,
476 in the scope SCOPE. */
478 bind (tree name, tree decl, struct c_scope *scope, bool invisible, bool nested)
480 struct c_binding *b, **here;
482 if (binding_freelist)
484 b = binding_freelist;
485 binding_freelist = b->prev;
488 b = GGC_NEW (struct c_binding);
493 b->depth = scope->depth;
494 b->invisible = invisible;
500 b->prev = scope->bindings;
506 switch (TREE_CODE (decl))
508 case LABEL_DECL: here = &I_LABEL_BINDING (name); break;
511 case RECORD_TYPE: here = &I_TAG_BINDING (name); break;
517 case ERROR_MARK: here = &I_SYMBOL_BINDING (name); break;
523 /* Locate the appropriate place in the chain of shadowed decls
524 to insert this binding. Normally, scope == current_scope and
525 this does nothing. */
526 while (*here && (*here)->depth > scope->depth)
527 here = &(*here)->shadowed;
533 /* Clear the binding structure B, stick it on the binding_freelist,
534 and return the former value of b->prev. This is used by pop_scope
535 and get_parm_info to iterate destructively over all the bindings
536 from a given scope. */
537 static struct c_binding *
538 free_binding_and_advance (struct c_binding *b)
540 struct c_binding *prev = b->prev;
542 memset (b, 0, sizeof (struct c_binding));
543 b->prev = binding_freelist;
544 binding_freelist = b;
550 /* Hook called at end of compilation to assume 1 elt
551 for a file-scope tentative array defn that wasn't complete before. */
554 c_finish_incomplete_decl (tree decl)
556 if (TREE_CODE (decl) == VAR_DECL)
558 tree type = TREE_TYPE (decl);
559 if (type != error_mark_node
560 && TREE_CODE (type) == ARRAY_TYPE
561 && !DECL_EXTERNAL (decl)
562 && TYPE_DOMAIN (type) == 0)
564 warning (0, "array %q+D assumed to have one element", decl);
566 complete_array_type (&TREE_TYPE (decl), NULL_TREE, true);
568 layout_decl (decl, 0);
573 /* The Objective-C front-end often needs to determine the current scope. */
576 objc_get_current_scope (void)
578 return current_scope;
581 /* The following function is used only by Objective-C. It needs to live here
582 because it accesses the innards of c_scope. */
585 objc_mark_locals_volatile (void *enclosing_blk)
587 struct c_scope *scope;
590 for (scope = current_scope;
591 scope && scope != enclosing_blk;
592 scope = scope->outer)
594 for (b = scope->bindings; b; b = b->prev)
595 objc_volatilize_decl (b->decl);
597 /* Do not climb up past the current function. */
598 if (scope->function_body)
603 /* Nonzero if we are currently in file scope. */
606 global_bindings_p (void)
608 return current_scope == file_scope && !c_override_global_bindings_to_false;
612 keep_next_level (void)
614 keep_next_level_flag = true;
617 /* Identify this scope as currently being filled with parameters. */
620 declare_parm_level (void)
622 current_scope->parm_flag = true;
628 if (next_is_function_body)
630 /* This is the transition from the parameters to the top level
631 of the function body. These are the same scope
632 (C99 6.2.1p4,6) so we do not push another scope structure.
633 next_is_function_body is set only by store_parm_decls, which
634 in turn is called when and only when we are about to
635 encounter the opening curly brace for the function body.
637 The outermost block of a function always gets a BLOCK node,
638 because the debugging output routines expect that each
639 function has at least one BLOCK. */
640 current_scope->parm_flag = false;
641 current_scope->function_body = true;
642 current_scope->keep = true;
643 current_scope->outer_function = current_function_scope;
644 current_function_scope = current_scope;
646 keep_next_level_flag = false;
647 next_is_function_body = false;
651 struct c_scope *scope;
654 scope = scope_freelist;
655 scope_freelist = scope->outer;
658 scope = GGC_CNEW (struct c_scope);
660 scope->keep = keep_next_level_flag;
661 scope->outer = current_scope;
662 scope->depth = current_scope ? (current_scope->depth + 1) : 0;
664 /* Check for scope depth overflow. Unlikely (2^28 == 268,435,456) but
666 if (current_scope && scope->depth == 0)
669 sorry ("GCC supports only %u nested scopes", scope->depth);
672 current_scope = scope;
673 keep_next_level_flag = false;
677 /* Set the TYPE_CONTEXT of all of TYPE's variants to CONTEXT. */
680 set_type_context (tree type, tree context)
682 for (type = TYPE_MAIN_VARIANT (type); type;
683 type = TYPE_NEXT_VARIANT (type))
684 TYPE_CONTEXT (type) = context;
687 /* Exit a scope. Restore the state of the identifier-decl mappings
688 that were in effect when this scope was entered. Return a BLOCK
689 node containing all the DECLs in this scope that are of interest
690 to debug info generation. */
695 struct c_scope *scope = current_scope;
696 tree block, context, p;
699 bool functionbody = scope->function_body;
700 bool keep = functionbody || scope->keep || scope->bindings;
702 c_end_vm_scope (scope->depth);
704 /* If appropriate, create a BLOCK to record the decls for the life
709 block = make_node (BLOCK);
710 BLOCK_SUBBLOCKS (block) = scope->blocks;
711 TREE_USED (block) = 1;
713 /* In each subblock, record that this is its superior. */
714 for (p = scope->blocks; p; p = TREE_CHAIN (p))
715 BLOCK_SUPERCONTEXT (p) = block;
717 BLOCK_VARS (block) = 0;
720 /* The TYPE_CONTEXTs for all of the tagged types belonging to this
721 scope must be set so that they point to the appropriate
722 construct, i.e. either to the current FUNCTION_DECL node, or
723 else to the BLOCK node we just constructed.
725 Note that for tagged types whose scope is just the formal
726 parameter list for some function type specification, we can't
727 properly set their TYPE_CONTEXTs here, because we don't have a
728 pointer to the appropriate FUNCTION_TYPE node readily available
729 to us. For those cases, the TYPE_CONTEXTs of the relevant tagged
730 type nodes get set in `grokdeclarator' as soon as we have created
731 the FUNCTION_TYPE node which will represent the "scope" for these
732 "parameter list local" tagged types. */
733 if (scope->function_body)
734 context = current_function_decl;
735 else if (scope == file_scope)
737 tree file_decl = build_decl (TRANSLATION_UNIT_DECL, 0, 0);
738 TREE_CHAIN (file_decl) = all_translation_units;
739 all_translation_units = file_decl;
745 /* Clear all bindings in this scope. */
746 for (b = scope->bindings; b; b = free_binding_and_advance (b))
749 switch (TREE_CODE (p))
752 /* Warnings for unused labels, errors for undefined labels. */
753 if (TREE_USED (p) && !DECL_INITIAL (p))
755 error ("label %q+D used but not defined", p);
756 DECL_INITIAL (p) = error_mark_node;
758 else if (!TREE_USED (p) && warn_unused_label)
760 if (DECL_INITIAL (p))
761 warning (0, "label %q+D defined but not used", p);
763 warning (0, "label %q+D declared but not defined", p);
765 /* Labels go in BLOCK_VARS. */
766 TREE_CHAIN (p) = BLOCK_VARS (block);
767 BLOCK_VARS (block) = p;
768 gcc_assert (I_LABEL_BINDING (b->id) == b);
769 I_LABEL_BINDING (b->id) = b->shadowed;
775 set_type_context (p, context);
777 /* Types may not have tag-names, in which case the type
778 appears in the bindings list with b->id NULL. */
781 gcc_assert (I_TAG_BINDING (b->id) == b);
782 I_TAG_BINDING (b->id) = b->shadowed;
787 /* Propagate TREE_ADDRESSABLE from nested functions to their
788 containing functions. */
789 if (!TREE_ASM_WRITTEN (p)
790 && DECL_INITIAL (p) != 0
791 && TREE_ADDRESSABLE (p)
792 && DECL_ABSTRACT_ORIGIN (p) != 0
793 && DECL_ABSTRACT_ORIGIN (p) != p)
794 TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (p)) = 1;
795 if (!DECL_EXTERNAL (p)
796 && DECL_INITIAL (p) == 0)
798 error ("nested function %q+D declared but never defined", p);
799 undef_nested_function = true;
804 /* Warnings for unused variables. */
806 && !DECL_IN_SYSTEM_HEADER (p)
808 && !DECL_ARTIFICIAL (p)
809 && scope != file_scope
810 && scope != external_scope)
811 warning (OPT_Wunused_variable, "unused variable %q+D", p);
815 error ("type of array %q+D completed incompatibly with"
816 " implicit initialization", p);
823 /* All of these go in BLOCK_VARS, but only if this is the
824 binding in the home scope. */
827 TREE_CHAIN (p) = BLOCK_VARS (block);
828 BLOCK_VARS (block) = p;
830 /* If this is the file scope, and we are processing more
831 than one translation unit in this compilation, set
832 DECL_CONTEXT of each decl to the TRANSLATION_UNIT_DECL.
833 This makes same_translation_unit_p work, and causes
834 static declarations to be given disambiguating suffixes. */
835 if (scope == file_scope && num_in_fnames > 1)
837 DECL_CONTEXT (p) = context;
838 if (TREE_CODE (p) == TYPE_DECL)
839 set_type_context (TREE_TYPE (p), context);
843 /* Parameters go in DECL_ARGUMENTS, not BLOCK_VARS, and have
844 already been put there by store_parm_decls. Unused-
845 parameter warnings are handled by function.c.
846 error_mark_node obviously does not go in BLOCK_VARS and
847 does not get unused-variable warnings. */
850 /* It is possible for a decl not to have a name. We get
851 here with b->id NULL in this case. */
854 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
855 I_SYMBOL_BINDING (b->id) = b->shadowed;
856 if (b->shadowed && b->shadowed->type)
857 TREE_TYPE (b->shadowed->decl) = b->shadowed->type;
867 /* Dispose of the block that we just made inside some higher level. */
868 if ((scope->function_body || scope == file_scope) && context)
870 DECL_INITIAL (context) = block;
871 BLOCK_SUPERCONTEXT (block) = context;
873 else if (scope->outer)
876 SCOPE_LIST_APPEND (scope->outer, blocks, block);
877 /* If we did not make a block for the scope just exited, any
878 blocks made for inner scopes must be carried forward so they
879 will later become subblocks of something else. */
880 else if (scope->blocks)
881 SCOPE_LIST_CONCAT (scope->outer, blocks, scope, blocks);
884 /* Pop the current scope, and free the structure for reuse. */
885 current_scope = scope->outer;
886 if (scope->function_body)
887 current_function_scope = scope->outer_function;
889 memset (scope, 0, sizeof (struct c_scope));
890 scope->outer = scope_freelist;
891 scope_freelist = scope;
897 push_file_scope (void)
905 file_scope = current_scope;
907 start_fname_decls ();
909 for (decl = visible_builtins; decl; decl = TREE_CHAIN (decl))
910 bind (DECL_NAME (decl), decl, file_scope,
911 /*invisible=*/false, /*nested=*/true);
915 pop_file_scope (void)
917 /* In case there were missing closebraces, get us back to the global
919 while (current_scope != file_scope)
922 /* __FUNCTION__ is defined at file scope (""). This
923 call may not be necessary as my tests indicate it
924 still works without it. */
925 finish_fname_decls ();
927 /* This is the point to write out a PCH if we're doing that.
928 In that case we do not want to do anything else. */
931 c_common_write_pch ();
935 /* Pop off the file scope and close this translation unit. */
939 maybe_apply_pending_pragma_weaks ();
940 cgraph_finalize_compilation_unit ();
943 /* Insert BLOCK at the end of the list of subblocks of the current
944 scope. This is used when a BIND_EXPR is expanded, to handle the
945 BLOCK node inside the BIND_EXPR. */
948 insert_block (tree block)
950 TREE_USED (block) = 1;
951 SCOPE_LIST_APPEND (current_scope, blocks, block);
954 /* Push a definition or a declaration of struct, union or enum tag "name".
955 "type" should be the type node.
956 We assume that the tag "name" is not already defined.
958 Note that the definition may really be just a forward reference.
959 In that case, the TYPE_SIZE will be zero. */
962 pushtag (tree name, tree type)
964 /* Record the identifier as the type's name if it has none. */
965 if (name && !TYPE_NAME (type))
966 TYPE_NAME (type) = name;
967 bind (name, type, current_scope, /*invisible=*/false, /*nested=*/false);
969 /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
970 tagged type we just added to the current scope. This fake
971 NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
972 to output a representation of a tagged type, and it also gives
973 us a convenient place to record the "scope start" address for the
976 TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));
978 /* An approximation for now, so we can tell this is a function-scope tag.
979 This will be updated in pop_scope. */
980 TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
983 /* Subroutine of compare_decls. Allow harmless mismatches in return
984 and argument types provided that the type modes match. This function
985 return a unified type given a suitable match, and 0 otherwise. */
988 match_builtin_function_types (tree newtype, tree oldtype)
990 tree newrettype, oldrettype;
991 tree newargs, oldargs;
992 tree trytype, tryargs;
994 /* Accept the return type of the new declaration if same modes. */
995 oldrettype = TREE_TYPE (oldtype);
996 newrettype = TREE_TYPE (newtype);
998 if (TYPE_MODE (oldrettype) != TYPE_MODE (newrettype))
1001 oldargs = TYPE_ARG_TYPES (oldtype);
1002 newargs = TYPE_ARG_TYPES (newtype);
1005 while (oldargs || newargs)
1009 || !TREE_VALUE (oldargs)
1010 || !TREE_VALUE (newargs)
1011 || TYPE_MODE (TREE_VALUE (oldargs))
1012 != TYPE_MODE (TREE_VALUE (newargs)))
1015 oldargs = TREE_CHAIN (oldargs);
1016 newargs = TREE_CHAIN (newargs);
1019 trytype = build_function_type (newrettype, tryargs);
1020 return build_type_attribute_variant (trytype, TYPE_ATTRIBUTES (oldtype));
1023 /* Subroutine of diagnose_mismatched_decls. Check for function type
1024 mismatch involving an empty arglist vs a nonempty one and give clearer
1027 diagnose_arglist_conflict (tree newdecl, tree olddecl,
1028 tree newtype, tree oldtype)
1032 if (TREE_CODE (olddecl) != FUNCTION_DECL
1033 || !comptypes (TREE_TYPE (oldtype), TREE_TYPE (newtype))
1034 || !((TYPE_ARG_TYPES (oldtype) == 0 && DECL_INITIAL (olddecl) == 0)
1036 (TYPE_ARG_TYPES (newtype) == 0 && DECL_INITIAL (newdecl) == 0)))
1039 t = TYPE_ARG_TYPES (oldtype);
1041 t = TYPE_ARG_TYPES (newtype);
1042 for (; t; t = TREE_CHAIN (t))
1044 tree type = TREE_VALUE (t);
1046 if (TREE_CHAIN (t) == 0
1047 && TYPE_MAIN_VARIANT (type) != void_type_node)
1049 inform ("a parameter list with an ellipsis can%'t match "
1050 "an empty parameter name list declaration");
1054 if (c_type_promotes_to (type) != type)
1056 inform ("an argument type that has a default promotion can%'t match "
1057 "an empty parameter name list declaration");
1063 /* Another subroutine of diagnose_mismatched_decls. OLDDECL is an
1064 old-style function definition, NEWDECL is a prototype declaration.
1065 Diagnose inconsistencies in the argument list. Returns TRUE if
1066 the prototype is compatible, FALSE if not. */
1068 validate_proto_after_old_defn (tree newdecl, tree newtype, tree oldtype)
1070 tree newargs, oldargs;
1073 #define END_OF_ARGLIST(t) ((t) == void_type_node)
1075 oldargs = TYPE_ACTUAL_ARG_TYPES (oldtype);
1076 newargs = TYPE_ARG_TYPES (newtype);
1081 tree oldargtype = TYPE_MAIN_VARIANT (TREE_VALUE (oldargs));
1082 tree newargtype = TYPE_MAIN_VARIANT (TREE_VALUE (newargs));
1084 if (END_OF_ARGLIST (oldargtype) && END_OF_ARGLIST (newargtype))
1087 /* Reaching the end of just one list means the two decls don't
1088 agree on the number of arguments. */
1089 if (END_OF_ARGLIST (oldargtype))
1091 error ("prototype for %q+D declares more arguments "
1092 "than previous old-style definition", newdecl);
1095 else if (END_OF_ARGLIST (newargtype))
1097 error ("prototype for %q+D declares fewer arguments "
1098 "than previous old-style definition", newdecl);
1102 /* Type for passing arg must be consistent with that declared
1104 else if (!comptypes (oldargtype, newargtype))
1106 error ("prototype for %q+D declares argument %d"
1107 " with incompatible type",
1112 oldargs = TREE_CHAIN (oldargs);
1113 newargs = TREE_CHAIN (newargs);
1117 /* If we get here, no errors were found, but do issue a warning
1118 for this poor-style construct. */
1119 warning (0, "prototype for %q+D follows non-prototype definition",
1122 #undef END_OF_ARGLIST
1125 /* Subroutine of diagnose_mismatched_decls. Report the location of DECL,
1126 first in a pair of mismatched declarations, using the diagnostic
1129 locate_old_decl (tree decl, void (*diag)(const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2))
1131 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1133 else if (DECL_INITIAL (decl))
1134 diag (G_("previous definition of %q+D was here"), decl);
1135 else if (C_DECL_IMPLICIT (decl))
1136 diag (G_("previous implicit declaration of %q+D was here"), decl);
1138 diag (G_("previous declaration of %q+D was here"), decl);
1141 /* Subroutine of duplicate_decls. Compare NEWDECL to OLDDECL.
1142 Returns true if the caller should proceed to merge the two, false
1143 if OLDDECL should simply be discarded. As a side effect, issues
1144 all necessary diagnostics for invalid or poor-style combinations.
1145 If it returns true, writes the types of NEWDECL and OLDDECL to
1146 *NEWTYPEP and *OLDTYPEP - these may have been adjusted from
1147 TREE_TYPE (NEWDECL, OLDDECL) respectively. */
1150 diagnose_mismatched_decls (tree newdecl, tree olddecl,
1151 tree *newtypep, tree *oldtypep)
1153 tree newtype, oldtype;
1154 bool pedwarned = false;
1155 bool warned = false;
1158 #define DECL_EXTERN_INLINE(DECL) (DECL_DECLARED_INLINE_P (DECL) \
1159 && DECL_EXTERNAL (DECL))
1161 /* If we have error_mark_node for either decl or type, just discard
1162 the previous decl - we're in an error cascade already. */
1163 if (olddecl == error_mark_node || newdecl == error_mark_node)
1165 *oldtypep = oldtype = TREE_TYPE (olddecl);
1166 *newtypep = newtype = TREE_TYPE (newdecl);
1167 if (oldtype == error_mark_node || newtype == error_mark_node)
1170 /* Two different categories of symbol altogether. This is an error
1171 unless OLDDECL is a builtin. OLDDECL will be discarded in any case. */
1172 if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1174 if (!(TREE_CODE (olddecl) == FUNCTION_DECL
1175 && DECL_BUILT_IN (olddecl)
1176 && !C_DECL_DECLARED_BUILTIN (olddecl)))
1178 error ("%q+D redeclared as different kind of symbol", newdecl);
1179 locate_old_decl (olddecl, error);
1181 else if (TREE_PUBLIC (newdecl))
1182 warning (0, "built-in function %q+D declared as non-function",
1185 warning (OPT_Wshadow, "declaration of %q+D shadows "
1186 "a built-in function", newdecl);
1190 /* Enumerators have no linkage, so may only be declared once in a
1192 if (TREE_CODE (olddecl) == CONST_DECL)
1194 error ("redeclaration of enumerator %q+D", newdecl);
1195 locate_old_decl (olddecl, error);
1199 if (!comptypes (oldtype, newtype))
1201 if (TREE_CODE (olddecl) == FUNCTION_DECL
1202 && DECL_BUILT_IN (olddecl) && !C_DECL_DECLARED_BUILTIN (olddecl))
1204 /* Accept harmless mismatch in function types.
1205 This is for the ffs and fprintf builtins. */
1206 tree trytype = match_builtin_function_types (newtype, oldtype);
1208 if (trytype && comptypes (newtype, trytype))
1209 *oldtypep = oldtype = trytype;
1212 /* If types don't match for a built-in, throw away the
1213 built-in. No point in calling locate_old_decl here, it
1214 won't print anything. */
1215 warning (0, "conflicting types for built-in function %q+D",
1220 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1221 && DECL_IS_BUILTIN (olddecl))
1223 /* A conflicting function declaration for a predeclared
1224 function that isn't actually built in. Objective C uses
1225 these. The new declaration silently overrides everything
1226 but the volatility (i.e. noreturn) indication. See also
1227 below. FIXME: Make Objective C use normal builtins. */
1228 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1231 /* Permit void foo (...) to match int foo (...) if the latter is
1232 the definition and implicit int was used. See
1233 c-torture/compile/920625-2.c. */
1234 else if (TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl)
1235 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == void_type_node
1236 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == integer_type_node
1237 && C_FUNCTION_IMPLICIT_INT (newdecl) && !DECL_INITIAL (olddecl))
1239 pedwarn ("conflicting types for %q+D", newdecl);
1240 /* Make sure we keep void as the return type. */
1241 TREE_TYPE (newdecl) = *newtypep = newtype = oldtype;
1242 C_FUNCTION_IMPLICIT_INT (newdecl) = 0;
1245 /* Permit void foo (...) to match an earlier call to foo (...) with
1246 no declared type (thus, implicitly int). */
1247 else if (TREE_CODE (newdecl) == FUNCTION_DECL
1248 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == void_type_node
1249 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == integer_type_node
1250 && C_DECL_IMPLICIT (olddecl) && !DECL_INITIAL (olddecl))
1252 pedwarn ("conflicting types for %q+D", newdecl);
1253 /* Make sure we keep void as the return type. */
1254 TREE_TYPE (olddecl) = *oldtypep = oldtype = newtype;
1259 if (TYPE_QUALS (newtype) != TYPE_QUALS (oldtype))
1260 error ("conflicting type qualifiers for %q+D", newdecl);
1262 error ("conflicting types for %q+D", newdecl);
1263 diagnose_arglist_conflict (newdecl, olddecl, newtype, oldtype);
1264 locate_old_decl (olddecl, error);
1269 /* Redeclaration of a type is a constraint violation (6.7.2.3p1),
1270 but silently ignore the redeclaration if either is in a system
1271 header. (Conflicting redeclarations were handled above.) */
1272 if (TREE_CODE (newdecl) == TYPE_DECL)
1274 if (DECL_IN_SYSTEM_HEADER (newdecl) || DECL_IN_SYSTEM_HEADER (olddecl))
1275 return true; /* Allow OLDDECL to continue in use. */
1277 error ("redefinition of typedef %q+D", newdecl);
1278 locate_old_decl (olddecl, error);
1282 /* Function declarations can either be 'static' or 'extern' (no
1283 qualifier is equivalent to 'extern' - C99 6.2.2p5) and therefore
1284 can never conflict with each other on account of linkage (6.2.2p4).
1285 Multiple definitions are not allowed (6.9p3,5) but GCC permits
1286 two definitions if one is 'extern inline' and one is not. The non-
1287 extern-inline definition supersedes the extern-inline definition. */
1289 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
1291 /* If you declare a built-in function name as static, or
1292 define the built-in with an old-style definition (so we
1293 can't validate the argument list) the built-in definition is
1294 overridden, but optionally warn this was a bad choice of name. */
1295 if (DECL_BUILT_IN (olddecl)
1296 && !C_DECL_DECLARED_BUILTIN (olddecl)
1297 && (!TREE_PUBLIC (newdecl)
1298 || (DECL_INITIAL (newdecl)
1299 && !TYPE_ARG_TYPES (TREE_TYPE (newdecl)))))
1301 warning (OPT_Wshadow, "declaration of %q+D shadows "
1302 "a built-in function", newdecl);
1303 /* Discard the old built-in function. */
1307 if (DECL_INITIAL (newdecl))
1309 if (DECL_INITIAL (olddecl))
1311 /* If both decls are in the same TU and the new declaration
1312 isn't overriding an extern inline reject the new decl.
1313 When we handle c99 style inline rules we'll want to reject
1316 DECL_EXTERN_INLINE (olddecl)
1317 && !DECL_EXTERN_INLINE (newdecl)
1319 if they're in the same translation unit. Until we implement
1320 the full semantics we accept the construct. */
1321 if (!(DECL_EXTERN_INLINE (olddecl)
1322 && !DECL_EXTERN_INLINE (newdecl))
1323 && same_translation_unit_p (newdecl, olddecl))
1325 error ("redefinition of %q+D", newdecl);
1326 locate_old_decl (olddecl, error);
1331 /* If we have a prototype after an old-style function definition,
1332 the argument types must be checked specially. */
1333 else if (DECL_INITIAL (olddecl)
1334 && !TYPE_ARG_TYPES (oldtype) && TYPE_ARG_TYPES (newtype)
1335 && TYPE_ACTUAL_ARG_TYPES (oldtype)
1336 && !validate_proto_after_old_defn (newdecl, newtype, oldtype))
1338 locate_old_decl (olddecl, error);
1341 /* A non-static declaration (even an "extern") followed by a
1342 static declaration is undefined behavior per C99 6.2.2p3-5,7.
1343 The same is true for a static forward declaration at block
1344 scope followed by a non-static declaration/definition at file
1345 scope. Static followed by non-static at the same scope is
1346 not undefined behavior, and is the most convenient way to get
1347 some effects (see e.g. what unwind-dw2-fde-glibc.c does to
1348 the definition of _Unwind_Find_FDE in unwind-dw2-fde.c), but
1349 we do diagnose it if -Wtraditional. */
1350 if (TREE_PUBLIC (olddecl) && !TREE_PUBLIC (newdecl))
1352 /* Two exceptions to the rule. If olddecl is an extern
1353 inline, or a predeclared function that isn't actually
1354 built in, newdecl silently overrides olddecl. The latter
1355 occur only in Objective C; see also above. (FIXME: Make
1356 Objective C use normal builtins.) */
1357 if (!DECL_IS_BUILTIN (olddecl)
1358 && !DECL_EXTERN_INLINE (olddecl))
1360 error ("static declaration of %q+D follows "
1361 "non-static declaration", newdecl);
1362 locate_old_decl (olddecl, error);
1366 else if (TREE_PUBLIC (newdecl) && !TREE_PUBLIC (olddecl))
1368 if (DECL_CONTEXT (olddecl))
1370 error ("non-static declaration of %q+D follows "
1371 "static declaration", newdecl);
1372 locate_old_decl (olddecl, error);
1375 else if (warn_traditional)
1377 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1378 "follows static declaration", newdecl);
1383 else if (TREE_CODE (newdecl) == VAR_DECL)
1385 /* Only variables can be thread-local, and all declarations must
1386 agree on this property. */
1387 if (DECL_THREAD_LOCAL_P (newdecl) != DECL_THREAD_LOCAL_P (olddecl))
1389 if (DECL_THREAD_LOCAL_P (newdecl))
1390 error ("thread-local declaration of %q+D follows "
1391 "non-thread-local declaration", newdecl);
1393 error ("non-thread-local declaration of %q+D follows "
1394 "thread-local declaration", newdecl);
1396 locate_old_decl (olddecl, error);
1400 /* Multiple initialized definitions are not allowed (6.9p3,5). */
1401 if (DECL_INITIAL (newdecl) && DECL_INITIAL (olddecl))
1403 error ("redefinition of %q+D", newdecl);
1404 locate_old_decl (olddecl, error);
1408 /* Objects declared at file scope: if the first declaration had
1409 external linkage (even if it was an external reference) the
1410 second must have external linkage as well, or the behavior is
1411 undefined. If the first declaration had internal linkage, then
1412 the second must too, or else be an external reference (in which
1413 case the composite declaration still has internal linkage).
1414 As for function declarations, we warn about the static-then-
1415 extern case only for -Wtraditional. See generally 6.2.2p3-5,7. */
1416 if (DECL_FILE_SCOPE_P (newdecl)
1417 && TREE_PUBLIC (newdecl) != TREE_PUBLIC (olddecl))
1419 if (DECL_EXTERNAL (newdecl))
1421 if (!DECL_FILE_SCOPE_P (olddecl))
1423 error ("extern declaration of %q+D follows "
1424 "declaration with no linkage", newdecl);
1425 locate_old_decl (olddecl, error);
1428 else if (warn_traditional)
1430 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1431 "follows static declaration", newdecl);
1437 if (TREE_PUBLIC (newdecl))
1438 error ("non-static declaration of %q+D follows "
1439 "static declaration", newdecl);
1441 error ("static declaration of %q+D follows "
1442 "non-static declaration", newdecl);
1444 locate_old_decl (olddecl, error);
1448 /* Two objects with the same name declared at the same block
1449 scope must both be external references (6.7p3). */
1450 else if (!DECL_FILE_SCOPE_P (newdecl))
1452 if (DECL_EXTERNAL (newdecl))
1454 /* Extern with initializer at block scope, which will
1455 already have received an error. */
1457 else if (DECL_EXTERNAL (olddecl))
1459 error ("declaration of %q+D with no linkage follows "
1460 "extern declaration", newdecl);
1461 locate_old_decl (olddecl, error);
1465 error ("redeclaration of %q+D with no linkage", newdecl);
1466 locate_old_decl (olddecl, error);
1474 /* All decls must agree on a visibility. */
1475 if (CODE_CONTAINS_STRUCT (TREE_CODE (newdecl), TS_DECL_WITH_VIS)
1476 && DECL_VISIBILITY_SPECIFIED (newdecl) && DECL_VISIBILITY_SPECIFIED (olddecl)
1477 && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
1479 warning (0, "redeclaration of %q+D with different visibility "
1480 "(old visibility preserved)", newdecl);
1484 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1486 /* Diagnose inline __attribute__ ((noinline)) which is silly. */
1487 if (DECL_DECLARED_INLINE_P (newdecl)
1488 && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1490 warning (OPT_Wattributes, "inline declaration of %qD follows "
1491 "declaration with attribute noinline", newdecl);
1494 else if (DECL_DECLARED_INLINE_P (olddecl)
1495 && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1497 warning (OPT_Wattributes, "declaration of %q+D with attribute "
1498 "noinline follows inline declaration ", newdecl);
1502 /* Inline declaration after use or definition.
1503 ??? Should we still warn about this now we have unit-at-a-time
1504 mode and can get it right?
1505 Definitely don't complain if the decls are in different translation
1507 if (DECL_DECLARED_INLINE_P (newdecl) && !DECL_DECLARED_INLINE_P (olddecl)
1508 && same_translation_unit_p (olddecl, newdecl))
1510 if (TREE_USED (olddecl))
1512 warning (0, "%q+D declared inline after being called", olddecl);
1515 else if (DECL_INITIAL (olddecl))
1517 warning (0, "%q+D declared inline after its definition", olddecl);
1522 else /* PARM_DECL, VAR_DECL */
1524 /* Redeclaration of a parameter is a constraint violation (this is
1525 not explicitly stated, but follows from C99 6.7p3 [no more than
1526 one declaration of the same identifier with no linkage in the
1527 same scope, except type tags] and 6.2.2p6 [parameters have no
1528 linkage]). We must check for a forward parameter declaration,
1529 indicated by TREE_ASM_WRITTEN on the old declaration - this is
1530 an extension, the mandatory diagnostic for which is handled by
1531 mark_forward_parm_decls. */
1533 if (TREE_CODE (newdecl) == PARM_DECL
1534 && (!TREE_ASM_WRITTEN (olddecl) || TREE_ASM_WRITTEN (newdecl)))
1536 error ("redefinition of parameter %q+D", newdecl);
1537 locate_old_decl (olddecl, error);
1542 /* Optional warning for completely redundant decls. */
1543 if (!warned && !pedwarned
1544 && warn_redundant_decls
1545 /* Don't warn about a function declaration followed by a
1547 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1548 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl))
1549 /* Don't warn about redundant redeclarations of builtins. */
1550 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1551 && !DECL_BUILT_IN (newdecl)
1552 && DECL_BUILT_IN (olddecl)
1553 && !C_DECL_DECLARED_BUILTIN (olddecl))
1554 /* Don't warn about an extern followed by a definition. */
1555 && !(DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl))
1556 /* Don't warn about forward parameter decls. */
1557 && !(TREE_CODE (newdecl) == PARM_DECL
1558 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl)))
1560 warning (OPT_Wredundant_decls, "redundant redeclaration of %q+D",
1565 /* Report location of previous decl/defn in a consistent manner. */
1566 if (warned || pedwarned)
1567 locate_old_decl (olddecl, pedwarned ? pedwarn : warning0);
1569 #undef DECL_EXTERN_INLINE
1574 /* Subroutine of duplicate_decls. NEWDECL has been found to be
1575 consistent with OLDDECL, but carries new information. Merge the
1576 new information into OLDDECL. This function issues no
1580 merge_decls (tree newdecl, tree olddecl, tree newtype, tree oldtype)
1582 int new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
1583 && DECL_INITIAL (newdecl) != 0);
1584 int new_is_prototype = (TREE_CODE (newdecl) == FUNCTION_DECL
1585 && TYPE_ARG_TYPES (TREE_TYPE (newdecl)) != 0);
1586 int old_is_prototype = (TREE_CODE (olddecl) == FUNCTION_DECL
1587 && TYPE_ARG_TYPES (TREE_TYPE (olddecl)) != 0);
1589 /* For real parm decl following a forward decl, rechain the old decl
1590 in its new location and clear TREE_ASM_WRITTEN (it's not a
1591 forward decl anymore). */
1592 if (TREE_CODE (newdecl) == PARM_DECL
1593 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
1595 struct c_binding *b, **here;
1597 for (here = ¤t_scope->bindings; *here; here = &(*here)->prev)
1598 if ((*here)->decl == olddecl)
1605 b->prev = current_scope->bindings;
1606 current_scope->bindings = b;
1608 TREE_ASM_WRITTEN (olddecl) = 0;
1611 DECL_ATTRIBUTES (newdecl)
1612 = targetm.merge_decl_attributes (olddecl, newdecl);
1614 /* Merge the data types specified in the two decls. */
1616 = TREE_TYPE (olddecl)
1617 = composite_type (newtype, oldtype);
1619 /* Lay the type out, unless already done. */
1620 if (!comptypes (oldtype, TREE_TYPE (newdecl)))
1622 if (TREE_TYPE (newdecl) != error_mark_node)
1623 layout_type (TREE_TYPE (newdecl));
1624 if (TREE_CODE (newdecl) != FUNCTION_DECL
1625 && TREE_CODE (newdecl) != TYPE_DECL
1626 && TREE_CODE (newdecl) != CONST_DECL)
1627 layout_decl (newdecl, 0);
1631 /* Since the type is OLDDECL's, make OLDDECL's size go with. */
1632 DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
1633 DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
1634 DECL_MODE (newdecl) = DECL_MODE (olddecl);
1635 if (TREE_CODE (olddecl) != FUNCTION_DECL)
1636 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
1638 DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
1639 DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
1644 /* Merge the type qualifiers. */
1645 if (TREE_READONLY (newdecl))
1646 TREE_READONLY (olddecl) = 1;
1648 if (TREE_THIS_VOLATILE (newdecl))
1650 TREE_THIS_VOLATILE (olddecl) = 1;
1651 if (TREE_CODE (newdecl) == VAR_DECL)
1652 make_var_volatile (newdecl);
1655 /* Merge deprecatedness. */
1656 if (TREE_DEPRECATED (newdecl))
1657 TREE_DEPRECATED (olddecl) = 1;
1659 /* Keep source location of definition rather than declaration and of
1660 prototype rather than non-prototype unless that prototype is
1662 if ((DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0)
1663 || (old_is_prototype && !new_is_prototype
1664 && !C_DECL_BUILTIN_PROTOTYPE (olddecl)))
1665 DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
1667 /* Merge the unused-warning information. */
1668 if (DECL_IN_SYSTEM_HEADER (olddecl))
1669 DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1670 else if (DECL_IN_SYSTEM_HEADER (newdecl))
1671 DECL_IN_SYSTEM_HEADER (olddecl) = 1;
1673 /* Merge the initialization information. */
1674 if (DECL_INITIAL (newdecl) == 0)
1675 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1677 if (CODE_CONTAINS_STRUCT (TREE_CODE (olddecl), TS_DECL_WITH_VIS))
1679 /* Merge the section attribute.
1680 We want to issue an error if the sections conflict but that must be
1681 done later in decl_attributes since we are called before attributes
1683 if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
1684 DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
1686 /* Copy the assembler name.
1687 Currently, it can only be defined in the prototype. */
1688 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
1690 /* Use visibility of whichever declaration had it specified */
1691 if (DECL_VISIBILITY_SPECIFIED (olddecl))
1693 DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
1694 DECL_VISIBILITY_SPECIFIED (newdecl) = 1;
1697 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1699 DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
1700 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1701 DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
1702 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
1703 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
1704 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1705 TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
1706 DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
1707 DECL_IS_PURE (newdecl) |= DECL_IS_PURE (olddecl);
1708 DECL_IS_NOVOPS (newdecl) |= DECL_IS_NOVOPS (olddecl);
1711 /* Merge the storage class information. */
1712 merge_weak (newdecl, olddecl);
1714 /* For functions, static overrides non-static. */
1715 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1717 TREE_PUBLIC (newdecl) &= TREE_PUBLIC (olddecl);
1718 /* This is since we don't automatically
1719 copy the attributes of NEWDECL into OLDDECL. */
1720 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1721 /* If this clears `static', clear it in the identifier too. */
1722 if (!TREE_PUBLIC (olddecl))
1723 TREE_PUBLIC (DECL_NAME (olddecl)) = 0;
1727 if (DECL_EXTERNAL (newdecl))
1729 TREE_STATIC (newdecl) = TREE_STATIC (olddecl);
1730 DECL_EXTERNAL (newdecl) = DECL_EXTERNAL (olddecl);
1732 /* An extern decl does not override previous storage class. */
1733 TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
1734 if (!DECL_EXTERNAL (newdecl))
1736 DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
1737 DECL_COMMON (newdecl) = DECL_COMMON (olddecl);
1742 TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
1743 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1746 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1748 /* If we're redefining a function previously defined as extern
1749 inline, make sure we emit debug info for the inline before we
1750 throw it away, in case it was inlined into a function that hasn't
1751 been written out yet. */
1752 if (new_is_definition && DECL_INITIAL (olddecl))
1754 if (TREE_USED (olddecl)
1755 /* In unit-at-a-time mode we never inline re-defined extern
1756 inline functions. */
1757 && !flag_unit_at_a_time
1758 && cgraph_function_possibly_inlined_p (olddecl))
1759 (*debug_hooks->outlining_inline_function) (olddecl);
1761 /* The new defn must not be inline. */
1762 DECL_INLINE (newdecl) = 0;
1763 DECL_UNINLINABLE (newdecl) = 1;
1767 /* If either decl says `inline', this fn is inline,
1768 unless its definition was passed already. */
1769 if (DECL_DECLARED_INLINE_P (newdecl)
1770 || DECL_DECLARED_INLINE_P (olddecl))
1771 DECL_DECLARED_INLINE_P (newdecl) = 1;
1773 DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
1774 = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
1777 if (DECL_BUILT_IN (olddecl))
1779 /* If redeclaring a builtin function, it stays built in.
1780 But it gets tagged as having been declared. */
1781 DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
1782 DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
1783 C_DECL_DECLARED_BUILTIN (newdecl) = 1;
1784 if (new_is_prototype)
1785 C_DECL_BUILTIN_PROTOTYPE (newdecl) = 0;
1787 C_DECL_BUILTIN_PROTOTYPE (newdecl)
1788 = C_DECL_BUILTIN_PROTOTYPE (olddecl);
1791 /* Also preserve various other info from the definition. */
1792 if (!new_is_definition)
1794 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
1795 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1796 DECL_STRUCT_FUNCTION (newdecl) = DECL_STRUCT_FUNCTION (olddecl);
1797 DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
1798 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
1800 /* Set DECL_INLINE on the declaration if we've got a body
1801 from which to instantiate. */
1802 if (DECL_INLINE (olddecl) && !DECL_UNINLINABLE (newdecl))
1804 DECL_INLINE (newdecl) = 1;
1805 DECL_ABSTRACT_ORIGIN (newdecl)
1806 = DECL_ABSTRACT_ORIGIN (olddecl);
1811 /* If a previous declaration said inline, mark the
1812 definition as inlinable. */
1813 if (DECL_DECLARED_INLINE_P (newdecl)
1814 && !DECL_UNINLINABLE (newdecl))
1815 DECL_INLINE (newdecl) = 1;
1819 /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
1820 But preserve OLDDECL's DECL_UID and DECL_CONTEXT. */
1822 unsigned olddecl_uid = DECL_UID (olddecl);
1823 tree olddecl_context = DECL_CONTEXT (olddecl);
1825 memcpy ((char *) olddecl + sizeof (struct tree_common),
1826 (char *) newdecl + sizeof (struct tree_common),
1827 sizeof (struct tree_decl_common) - sizeof (struct tree_common));
1828 switch (TREE_CODE (olddecl))
1838 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1839 (char *) newdecl + sizeof (struct tree_decl_common),
1840 tree_code_size (TREE_CODE (olddecl)) - sizeof (struct tree_decl_common));
1845 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1846 (char *) newdecl + sizeof (struct tree_decl_common),
1847 sizeof (struct tree_decl_non_common) - sizeof (struct tree_decl_common));
1849 DECL_UID (olddecl) = olddecl_uid;
1850 DECL_CONTEXT (olddecl) = olddecl_context;
1853 /* If OLDDECL had its DECL_RTL instantiated, re-invoke make_decl_rtl
1854 so that encode_section_info has a chance to look at the new decl
1855 flags and attributes. */
1856 if (DECL_RTL_SET_P (olddecl)
1857 && (TREE_CODE (olddecl) == FUNCTION_DECL
1858 || (TREE_CODE (olddecl) == VAR_DECL
1859 && TREE_STATIC (olddecl))))
1860 make_decl_rtl (olddecl);
1863 /* Handle when a new declaration NEWDECL has the same name as an old
1864 one OLDDECL in the same binding contour. Prints an error message
1867 If safely possible, alter OLDDECL to look like NEWDECL, and return
1868 true. Otherwise, return false. */
1871 duplicate_decls (tree newdecl, tree olddecl)
1873 tree newtype = NULL, oldtype = NULL;
1875 if (!diagnose_mismatched_decls (newdecl, olddecl, &newtype, &oldtype))
1878 merge_decls (newdecl, olddecl, newtype, oldtype);
1883 /* Check whether decl-node NEW_DECL shadows an existing declaration. */
1885 warn_if_shadowing (tree new_decl)
1887 struct c_binding *b;
1889 /* Shadow warnings wanted? */
1891 /* No shadow warnings for internally generated vars. */
1892 || DECL_IS_BUILTIN (new_decl)
1893 /* No shadow warnings for vars made for inlining. */
1894 || DECL_FROM_INLINE (new_decl)
1895 /* Don't warn about the parm names in function declarator
1896 within a function declarator. It would be nice to avoid
1897 warning in any function declarator in a declaration, as
1898 opposed to a definition, but there is no way to tell
1899 it's not a definition at this point. */
1900 || (TREE_CODE (new_decl) == PARM_DECL && current_scope->outer->parm_flag))
1903 /* Is anything being shadowed? Invisible decls do not count. */
1904 for (b = I_SYMBOL_BINDING (DECL_NAME (new_decl)); b; b = b->shadowed)
1905 if (b->decl && b->decl != new_decl && !b->invisible)
1907 tree old_decl = b->decl;
1909 if (old_decl == error_mark_node)
1911 warning (0, "declaration of %q+D shadows previous non-variable",
1915 else if (TREE_CODE (old_decl) == PARM_DECL)
1916 warning (0, "declaration of %q+D shadows a parameter", new_decl);
1917 else if (DECL_FILE_SCOPE_P (old_decl))
1918 warning (0, "declaration of %q+D shadows a global declaration",
1920 else if (TREE_CODE (old_decl) == FUNCTION_DECL
1921 && DECL_BUILT_IN (old_decl))
1923 warning (0, "declaration of %q+D shadows a built-in function",
1928 warning (0, "declaration of %q+D shadows a previous local",
1931 warning (0, "%Jshadowed declaration is here", old_decl);
1938 /* Subroutine of pushdecl.
1940 X is a TYPE_DECL for a typedef statement. Create a brand new
1941 ..._TYPE node (which will be just a variant of the existing
1942 ..._TYPE node with identical properties) and then install X
1943 as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
1945 The whole point here is to end up with a situation where each
1946 and every ..._TYPE node the compiler creates will be uniquely
1947 associated with AT MOST one node representing a typedef name.
1948 This way, even though the compiler substitutes corresponding
1949 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
1950 early on, later parts of the compiler can always do the reverse
1951 translation and get back the corresponding typedef name. For
1954 typedef struct S MY_TYPE;
1957 Later parts of the compiler might only know that `object' was of
1958 type `struct S' if it were not for code just below. With this
1959 code however, later parts of the compiler see something like:
1961 struct S' == struct S
1962 typedef struct S' MY_TYPE;
1965 And they can then deduce (from the node for type struct S') that
1966 the original object declaration was:
1970 Being able to do this is important for proper support of protoize,
1971 and also for generating precise symbolic debugging information
1972 which takes full account of the programmer's (typedef) vocabulary.
1974 Obviously, we don't want to generate a duplicate ..._TYPE node if
1975 the TYPE_DECL node that we are now processing really represents a
1976 standard built-in type.
1978 Since all standard types are effectively declared at line zero
1979 in the source file, we can easily check to see if we are working
1980 on a standard type by checking the current value of lineno. */
1983 clone_underlying_type (tree x)
1985 if (DECL_IS_BUILTIN (x))
1987 if (TYPE_NAME (TREE_TYPE (x)) == 0)
1988 TYPE_NAME (TREE_TYPE (x)) = x;
1990 else if (TREE_TYPE (x) != error_mark_node
1991 && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
1993 tree tt = TREE_TYPE (x);
1994 DECL_ORIGINAL_TYPE (x) = tt;
1995 tt = build_variant_type_copy (tt);
1997 TREE_USED (tt) = TREE_USED (x);
2002 /* Record a decl-node X as belonging to the current lexical scope.
2003 Check for errors (such as an incompatible declaration for the same
2004 name already seen in the same scope).
2006 Returns either X or an old decl for the same name.
2007 If an old decl is returned, it may have been smashed
2008 to agree with what X says. */
2013 tree name = DECL_NAME (x);
2014 struct c_scope *scope = current_scope;
2015 struct c_binding *b;
2016 bool nested = false;
2018 /* Functions need the lang_decl data. */
2019 if (TREE_CODE (x) == FUNCTION_DECL && !DECL_LANG_SPECIFIC (x))
2020 DECL_LANG_SPECIFIC (x) = GGC_CNEW (struct lang_decl);
2022 /* Must set DECL_CONTEXT for everything not at file scope or
2023 DECL_FILE_SCOPE_P won't work. Local externs don't count
2024 unless they have initializers (which generate code). */
2025 if (current_function_decl
2026 && ((TREE_CODE (x) != FUNCTION_DECL && TREE_CODE (x) != VAR_DECL)
2027 || DECL_INITIAL (x) || !DECL_EXTERNAL (x)))
2028 DECL_CONTEXT (x) = current_function_decl;
2030 /* If this is of variably modified type, prevent jumping into its
2032 if ((TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == TYPE_DECL)
2033 && variably_modified_type_p (TREE_TYPE (x), NULL_TREE))
2034 c_begin_vm_scope (scope->depth);
2036 /* Anonymous decls are just inserted in the scope. */
2039 bind (name, x, scope, /*invisible=*/false, /*nested=*/false);
2043 /* First, see if there is another declaration with the same name in
2044 the current scope. If there is, duplicate_decls may do all the
2045 work for us. If duplicate_decls returns false, that indicates
2046 two incompatible decls in the same scope; we are to silently
2047 replace the old one (duplicate_decls has issued all appropriate
2048 diagnostics). In particular, we should not consider possible
2049 duplicates in the external scope, or shadowing. */
2050 b = I_SYMBOL_BINDING (name);
2051 if (b && B_IN_SCOPE (b, scope))
2053 struct c_binding *b_ext, *b_use;
2054 tree type = TREE_TYPE (x);
2055 tree visdecl = b->decl;
2056 tree vistype = TREE_TYPE (visdecl);
2057 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
2058 && COMPLETE_TYPE_P (TREE_TYPE (x)))
2059 b->inner_comp = false;
2062 /* If this is an external linkage declaration, we should check
2063 for compatibility with the type in the external scope before
2064 setting the type at this scope based on the visible
2065 information only. */
2066 if (TREE_PUBLIC (x) && TREE_PUBLIC (visdecl))
2068 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
2069 b_ext = b_ext->shadowed;
2074 TREE_TYPE (b_use->decl) = b_use->type;
2077 if (duplicate_decls (x, b_use->decl))
2081 /* Save the updated type in the external scope and
2082 restore the proper type for this scope. */
2084 if (comptypes (vistype, type))
2085 thistype = composite_type (vistype, type);
2087 thistype = TREE_TYPE (b_use->decl);
2088 b_use->type = TREE_TYPE (b_use->decl);
2089 if (TREE_CODE (b_use->decl) == FUNCTION_DECL
2090 && DECL_BUILT_IN (b_use->decl))
2092 = build_type_attribute_variant (thistype,
2095 TREE_TYPE (b_use->decl) = thistype;
2100 goto skip_external_and_shadow_checks;
2103 /* All declarations with external linkage, and all external
2104 references, go in the external scope, no matter what scope is
2105 current. However, the binding in that scope is ignored for
2106 purposes of normal name lookup. A separate binding structure is
2107 created in the requested scope; this governs the normal
2108 visibility of the symbol.
2110 The binding in the externals scope is used exclusively for
2111 detecting duplicate declarations of the same object, no matter
2112 what scope they are in; this is what we do here. (C99 6.2.7p2:
2113 All declarations that refer to the same object or function shall
2114 have compatible type; otherwise, the behavior is undefined.) */
2115 if (DECL_EXTERNAL (x) || scope == file_scope)
2117 tree type = TREE_TYPE (x);
2120 bool type_saved = false;
2121 if (b && !B_IN_EXTERNAL_SCOPE (b)
2122 && (TREE_CODE (b->decl) == FUNCTION_DECL
2123 || TREE_CODE (b->decl) == VAR_DECL)
2124 && DECL_FILE_SCOPE_P (b->decl))
2127 vistype = TREE_TYPE (visdecl);
2129 if (scope != file_scope
2130 && !DECL_IN_SYSTEM_HEADER (x))
2131 warning (OPT_Wnested_externs, "nested extern declaration of %qD", x);
2133 while (b && !B_IN_EXTERNAL_SCOPE (b))
2135 /* If this decl might be modified, save its type. This is
2136 done here rather than when the decl is first bound
2137 because the type may change after first binding, through
2138 being completed or through attributes being added. If we
2139 encounter multiple such decls, only the first should have
2140 its type saved; the others will already have had their
2141 proper types saved and the types will not have changed as
2142 their scopes will not have been re-entered. */
2143 if (DECL_P (b->decl) && DECL_FILE_SCOPE_P (b->decl) && !type_saved)
2145 b->type = TREE_TYPE (b->decl);
2148 if (B_IN_FILE_SCOPE (b)
2149 && TREE_CODE (b->decl) == VAR_DECL
2150 && TREE_STATIC (b->decl)
2151 && TREE_CODE (TREE_TYPE (b->decl)) == ARRAY_TYPE
2152 && !TYPE_DOMAIN (TREE_TYPE (b->decl))
2153 && TREE_CODE (type) == ARRAY_TYPE
2154 && TYPE_DOMAIN (type)
2155 && TYPE_MAX_VALUE (TYPE_DOMAIN (type))
2156 && !integer_zerop (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
2158 /* Array type completed in inner scope, which should be
2159 diagnosed if the completion does not have size 1 and
2160 it does not get completed in the file scope. */
2161 b->inner_comp = true;
2166 /* If a matching external declaration has been found, set its
2167 type to the composite of all the types of that declaration.
2168 After the consistency checks, it will be reset to the
2169 composite of the visible types only. */
2170 if (b && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2172 TREE_TYPE (b->decl) = b->type;
2174 /* The point of the same_translation_unit_p check here is,
2175 we want to detect a duplicate decl for a construct like
2176 foo() { extern bar(); } ... static bar(); but not if
2177 they are in different translation units. In any case,
2178 the static does not go in the externals scope. */
2180 && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2181 && duplicate_decls (x, b->decl))
2186 if (comptypes (vistype, type))
2187 thistype = composite_type (vistype, type);
2189 thistype = TREE_TYPE (b->decl);
2193 b->type = TREE_TYPE (b->decl);
2194 if (TREE_CODE (b->decl) == FUNCTION_DECL && DECL_BUILT_IN (b->decl))
2196 = build_type_attribute_variant (thistype,
2197 TYPE_ATTRIBUTES (b->type));
2198 TREE_TYPE (b->decl) = thistype;
2199 bind (name, b->decl, scope, /*invisible=*/false, /*nested=*/true);
2202 else if (TREE_PUBLIC (x))
2204 if (visdecl && !b && duplicate_decls (x, visdecl))
2206 /* An external declaration at block scope referring to a
2207 visible entity with internal linkage. The composite
2208 type will already be correct for this scope, so we
2209 just need to fall through to make the declaration in
2216 bind (name, x, external_scope, /*invisible=*/true,
2223 warn_if_shadowing (x);
2225 skip_external_and_shadow_checks:
2226 if (TREE_CODE (x) == TYPE_DECL)
2227 clone_underlying_type (x);
2229 bind (name, x, scope, /*invisible=*/false, nested);
2231 /* If x's type is incomplete because it's based on a
2232 structure or union which has not yet been fully declared,
2233 attach it to that structure or union type, so we can go
2234 back and complete the variable declaration later, if the
2235 structure or union gets fully declared.
2237 If the input is erroneous, we can have error_mark in the type
2238 slot (e.g. "f(void a, ...)") - that doesn't count as an
2240 if (TREE_TYPE (x) != error_mark_node
2241 && !COMPLETE_TYPE_P (TREE_TYPE (x)))
2243 tree element = TREE_TYPE (x);
2245 while (TREE_CODE (element) == ARRAY_TYPE)
2246 element = TREE_TYPE (element);
2247 element = TYPE_MAIN_VARIANT (element);
2249 if ((TREE_CODE (element) == RECORD_TYPE
2250 || TREE_CODE (element) == UNION_TYPE)
2251 && (TREE_CODE (x) != TYPE_DECL
2252 || TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE)
2253 && !COMPLETE_TYPE_P (element))
2254 C_TYPE_INCOMPLETE_VARS (element)
2255 = tree_cons (NULL_TREE, x, C_TYPE_INCOMPLETE_VARS (element));
2260 /* Record X as belonging to file scope.
2261 This is used only internally by the Objective-C front end,
2262 and is limited to its needs. duplicate_decls is not called;
2263 if there is any preexisting decl for this identifier, it is an ICE. */
2266 pushdecl_top_level (tree x)
2269 bool nested = false;
2270 gcc_assert (TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == CONST_DECL);
2272 name = DECL_NAME (x);
2274 gcc_assert (TREE_CODE (x) == CONST_DECL || !I_SYMBOL_BINDING (name));
2276 if (TREE_PUBLIC (x))
2278 bind (name, x, external_scope, /*invisible=*/true, /*nested=*/false);
2282 bind (name, x, file_scope, /*invisible=*/false, nested);
2288 implicit_decl_warning (tree id, tree olddecl)
2290 void (*diag) (const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2);
2291 switch (mesg_implicit_function_declaration)
2294 case 1: diag = warning0; break;
2295 case 2: diag = error; break;
2296 default: gcc_unreachable ();
2299 diag (G_("implicit declaration of function %qE"), id);
2301 locate_old_decl (olddecl, diag);
2304 /* Generate an implicit declaration for identifier FUNCTIONID as a
2305 function of type int (). */
2308 implicitly_declare (tree functionid)
2310 struct c_binding *b;
2314 for (b = I_SYMBOL_BINDING (functionid); b; b = b->shadowed)
2316 if (B_IN_SCOPE (b, external_scope))
2325 if (decl == error_mark_node)
2328 /* FIXME: Objective-C has weird not-really-builtin functions
2329 which are supposed to be visible automatically. They wind up
2330 in the external scope because they're pushed before the file
2331 scope gets created. Catch this here and rebind them into the
2333 if (!DECL_BUILT_IN (decl) && DECL_IS_BUILTIN (decl))
2335 bind (functionid, decl, file_scope,
2336 /*invisible=*/false, /*nested=*/true);
2341 tree newtype = default_function_type;
2343 TREE_TYPE (decl) = b->type;
2344 /* Implicit declaration of a function already declared
2345 (somehow) in a different scope, or as a built-in.
2346 If this is the first time this has happened, warn;
2347 then recycle the old declaration but with the new type. */
2348 if (!C_DECL_IMPLICIT (decl))
2350 implicit_decl_warning (functionid, decl);
2351 C_DECL_IMPLICIT (decl) = 1;
2353 if (DECL_BUILT_IN (decl))
2355 newtype = build_type_attribute_variant (newtype,
2357 (TREE_TYPE (decl)));
2358 if (!comptypes (newtype, TREE_TYPE (decl)))
2360 warning (0, "incompatible implicit declaration of built-in"
2361 " function %qD", decl);
2362 newtype = TREE_TYPE (decl);
2367 if (!comptypes (newtype, TREE_TYPE (decl)))
2369 error ("incompatible implicit declaration of function %qD",
2371 locate_old_decl (decl, error);
2374 b->type = TREE_TYPE (decl);
2375 TREE_TYPE (decl) = newtype;
2376 bind (functionid, decl, current_scope,
2377 /*invisible=*/false, /*nested=*/true);
2382 /* Not seen before. */
2383 decl = build_decl (FUNCTION_DECL, functionid, default_function_type);
2384 DECL_EXTERNAL (decl) = 1;
2385 TREE_PUBLIC (decl) = 1;
2386 C_DECL_IMPLICIT (decl) = 1;
2387 implicit_decl_warning (functionid, 0);
2388 asmspec_tree = maybe_apply_renaming_pragma (decl, /*asmname=*/NULL);
2390 set_user_assembler_name (decl, TREE_STRING_POINTER (asmspec_tree));
2392 /* C89 says implicit declarations are in the innermost block.
2393 So we record the decl in the standard fashion. */
2394 decl = pushdecl (decl);
2396 /* No need to call objc_check_decl here - it's a function type. */
2397 rest_of_decl_compilation (decl, 0, 0);
2399 /* Write a record describing this implicit function declaration
2400 to the prototypes file (if requested). */
2401 gen_aux_info_record (decl, 0, 1, 0);
2403 /* Possibly apply some default attributes to this implicit declaration. */
2404 decl_attributes (&decl, NULL_TREE, 0);
2409 /* Issue an error message for a reference to an undeclared variable
2410 ID, including a reference to a builtin outside of function-call
2411 context. Establish a binding of the identifier to error_mark_node
2412 in an appropriate scope, which will suppress further errors for the
2413 same identifier. The error message should be given location LOC. */
2415 undeclared_variable (tree id, location_t loc)
2417 static bool already = false;
2418 struct c_scope *scope;
2420 if (current_function_decl == 0)
2422 error ("%H%qE undeclared here (not in a function)", &loc, id);
2423 scope = current_scope;
2427 error ("%H%qE undeclared (first use in this function)", &loc, id);
2431 error ("%H(Each undeclared identifier is reported only once", &loc);
2432 error ("%Hfor each function it appears in.)", &loc);
2436 /* If we are parsing old-style parameter decls, current_function_decl
2437 will be nonnull but current_function_scope will be null. */
2438 scope = current_function_scope ? current_function_scope : current_scope;
2440 bind (id, error_mark_node, scope, /*invisible=*/false, /*nested=*/false);
2443 /* Subroutine of lookup_label, declare_label, define_label: construct a
2444 LABEL_DECL with all the proper frills. */
2447 make_label (tree name, location_t location)
2449 tree label = build_decl (LABEL_DECL, name, void_type_node);
2451 DECL_CONTEXT (label) = current_function_decl;
2452 DECL_MODE (label) = VOIDmode;
2453 DECL_SOURCE_LOCATION (label) = location;
2458 /* Get the LABEL_DECL corresponding to identifier NAME as a label.
2459 Create one if none exists so far for the current function.
2460 This is called when a label is used in a goto expression or
2461 has its address taken. */
2464 lookup_label (tree name)
2468 if (current_function_decl == 0)
2470 error ("label %qE referenced outside of any function", name);
2474 /* Use a label already defined or ref'd with this name, but not if
2475 it is inherited from a containing function and wasn't declared
2477 label = I_LABEL_DECL (name);
2478 if (label && (DECL_CONTEXT (label) == current_function_decl
2479 || C_DECLARED_LABEL_FLAG (label)))
2481 /* If the label has only been declared, update its apparent
2482 location to point here, for better diagnostics if it
2483 turns out not to have been defined. */
2484 if (!TREE_USED (label))
2485 DECL_SOURCE_LOCATION (label) = input_location;
2489 /* No label binding for that identifier; make one. */
2490 label = make_label (name, input_location);
2492 /* Ordinary labels go in the current function scope. */
2493 bind (name, label, current_function_scope,
2494 /*invisible=*/false, /*nested=*/false);
2498 /* Make a label named NAME in the current function, shadowing silently
2499 any that may be inherited from containing functions or containing
2500 scopes. This is called for __label__ declarations. */
2503 declare_label (tree name)
2505 struct c_binding *b = I_LABEL_BINDING (name);
2508 /* Check to make sure that the label hasn't already been declared
2510 if (b && B_IN_CURRENT_SCOPE (b))
2512 error ("duplicate label declaration %qE", name);
2513 locate_old_decl (b->decl, error);
2515 /* Just use the previous declaration. */
2519 label = make_label (name, input_location);
2520 C_DECLARED_LABEL_FLAG (label) = 1;
2522 /* Declared labels go in the current scope. */
2523 bind (name, label, current_scope,
2524 /*invisible=*/false, /*nested=*/false);
2528 /* Define a label, specifying the location in the source file.
2529 Return the LABEL_DECL node for the label, if the definition is valid.
2530 Otherwise return 0. */
2533 define_label (location_t location, tree name)
2535 /* Find any preexisting label with this name. It is an error
2536 if that label has already been defined in this function, or
2537 if there is a containing function with a declared label with
2539 tree label = I_LABEL_DECL (name);
2540 struct c_label_list *nlist_se, *nlist_vm;
2543 && ((DECL_CONTEXT (label) == current_function_decl
2544 && DECL_INITIAL (label) != 0)
2545 || (DECL_CONTEXT (label) != current_function_decl
2546 && C_DECLARED_LABEL_FLAG (label))))
2548 error ("%Hduplicate label %qD", &location, label);
2549 locate_old_decl (label, error);
2552 else if (label && DECL_CONTEXT (label) == current_function_decl)
2554 /* The label has been used or declared already in this function,
2555 but not defined. Update its location to point to this
2557 if (C_DECL_UNDEFINABLE_STMT_EXPR (label))
2558 error ("%Jjump into statement expression", label);
2559 if (C_DECL_UNDEFINABLE_VM (label))
2560 error ("%Jjump into scope of identifier with variably modified type",
2562 DECL_SOURCE_LOCATION (label) = location;
2566 /* No label binding for that identifier; make one. */
2567 label = make_label (name, location);
2569 /* Ordinary labels go in the current function scope. */
2570 bind (name, label, current_function_scope,
2571 /*invisible=*/false, /*nested=*/false);
2574 if (!in_system_header && lookup_name (name))
2575 warning (OPT_Wtraditional, "%Htraditional C lacks a separate namespace "
2576 "for labels, identifier %qE conflicts", &location, name);
2578 nlist_se = XOBNEW (&parser_obstack, struct c_label_list);
2579 nlist_se->next = label_context_stack_se->labels_def;
2580 nlist_se->label = label;
2581 label_context_stack_se->labels_def = nlist_se;
2583 nlist_vm = XOBNEW (&parser_obstack, struct c_label_list);
2584 nlist_vm->next = label_context_stack_vm->labels_def;
2585 nlist_vm->label = label;
2586 label_context_stack_vm->labels_def = nlist_vm;
2588 /* Mark label as having been defined. */
2589 DECL_INITIAL (label) = error_mark_node;
2593 /* Given NAME, an IDENTIFIER_NODE,
2594 return the structure (or union or enum) definition for that name.
2595 If THISLEVEL_ONLY is nonzero, searches only the current_scope.
2596 CODE says which kind of type the caller wants;
2597 it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
2598 If the wrong kind of type is found, an error is reported. */
2601 lookup_tag (enum tree_code code, tree name, int thislevel_only)
2603 struct c_binding *b = I_TAG_BINDING (name);
2609 /* We only care about whether it's in this level if
2610 thislevel_only was set or it might be a type clash. */
2611 if (thislevel_only || TREE_CODE (b->decl) != code)
2613 /* For our purposes, a tag in the external scope is the same as
2614 a tag in the file scope. (Primarily relevant to Objective-C
2615 and its builtin structure tags, which get pushed before the
2616 file scope is created.) */
2617 if (B_IN_CURRENT_SCOPE (b)
2618 || (current_scope == file_scope && B_IN_EXTERNAL_SCOPE (b)))
2622 if (thislevel_only && !thislevel)
2625 if (TREE_CODE (b->decl) != code)
2627 /* Definition isn't the kind we were looking for. */
2628 pending_invalid_xref = name;
2629 pending_invalid_xref_location = input_location;
2631 /* If in the same binding level as a declaration as a tag
2632 of a different type, this must not be allowed to
2633 shadow that tag, so give the error immediately.
2634 (For example, "struct foo; union foo;" is invalid.) */
2636 pending_xref_error ();
2641 /* Print an error message now
2642 for a recent invalid struct, union or enum cross reference.
2643 We don't print them immediately because they are not invalid
2644 when used in the `struct foo;' construct for shadowing. */
2647 pending_xref_error (void)
2649 if (pending_invalid_xref != 0)
2650 error ("%H%qE defined as wrong kind of tag",
2651 &pending_invalid_xref_location, pending_invalid_xref);
2652 pending_invalid_xref = 0;
2656 /* Look up NAME in the current scope and its superiors
2657 in the namespace of variables, functions and typedefs.
2658 Return a ..._DECL node of some kind representing its definition,
2659 or return 0 if it is undefined. */
2662 lookup_name (tree name)
2664 struct c_binding *b = I_SYMBOL_BINDING (name);
2665 if (b && !b->invisible)
2670 /* Similar to `lookup_name' but look only at the indicated scope. */
2673 lookup_name_in_scope (tree name, struct c_scope *scope)
2675 struct c_binding *b;
2677 for (b = I_SYMBOL_BINDING (name); b; b = b->shadowed)
2678 if (B_IN_SCOPE (b, scope))
2683 /* Create the predefined scalar types of C,
2684 and some nodes representing standard constants (0, 1, (void *) 0).
2685 Initialize the global scope.
2686 Make definitions for built-in primitive functions. */
2689 c_init_decl_processing (void)
2691 location_t save_loc = input_location;
2693 /* Initialize reserved words for parser. */
2696 current_function_decl = 0;
2698 gcc_obstack_init (&parser_obstack);
2700 /* Make the externals scope. */
2702 external_scope = current_scope;
2704 /* Declarations from c_common_nodes_and_builtins must not be associated
2705 with this input file, lest we get differences between using and not
2706 using preprocessed headers. */
2707 #ifdef USE_MAPPED_LOCATION
2708 input_location = BUILTINS_LOCATION;
2710 input_location.file = "<built-in>";
2711 input_location.line = 0;
2714 build_common_tree_nodes (flag_signed_char, false);
2716 c_common_nodes_and_builtins ();
2718 /* In C, comparisons and TRUTH_* expressions have type int. */
2719 truthvalue_type_node = integer_type_node;
2720 truthvalue_true_node = integer_one_node;
2721 truthvalue_false_node = integer_zero_node;
2723 /* Even in C99, which has a real boolean type. */
2724 pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
2725 boolean_type_node));
2727 input_location = save_loc;
2729 pedantic_lvalues = true;
2731 make_fname_decl = c_make_fname_decl;
2732 start_fname_decls ();
2735 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
2736 decl, NAME is the initialization string and TYPE_DEP indicates whether
2737 NAME depended on the type of the function. As we don't yet implement
2738 delayed emission of static data, we mark the decl as emitted
2739 so it is not placed in the output. Anything using it must therefore pull
2740 out the STRING_CST initializer directly. FIXME. */
2743 c_make_fname_decl (tree id, int type_dep)
2745 const char *name = fname_as_string (type_dep);
2746 tree decl, type, init;
2747 size_t length = strlen (name);
2749 type = build_array_type (char_type_node,
2750 build_index_type (size_int (length)));
2751 type = c_build_qualified_type (type, TYPE_QUAL_CONST);
2753 decl = build_decl (VAR_DECL, id, type);
2755 TREE_STATIC (decl) = 1;
2756 TREE_READONLY (decl) = 1;
2757 DECL_ARTIFICIAL (decl) = 1;
2759 init = build_string (length + 1, name);
2760 free ((char *) name);
2761 TREE_TYPE (init) = type;
2762 DECL_INITIAL (decl) = init;
2764 TREE_USED (decl) = 1;
2766 if (current_function_decl)
2768 DECL_CONTEXT (decl) = current_function_decl;
2769 bind (id, decl, current_function_scope,
2770 /*invisible=*/false, /*nested=*/false);
2773 finish_decl (decl, init, NULL_TREE);
2778 /* Return a definition for a builtin function named NAME and whose data type
2779 is TYPE. TYPE should be a function type with argument types.
2780 FUNCTION_CODE tells later passes how to compile calls to this function.
2781 See tree.h for its possible values.
2783 If LIBRARY_NAME is nonzero, use that for DECL_ASSEMBLER_NAME,
2784 the name to be called if we can't opencode the function. If
2785 ATTRS is nonzero, use that for the function's attribute list. */
2788 builtin_function (const char *name, tree type, int function_code,
2789 enum built_in_class cl, const char *library_name,
2792 tree id = get_identifier (name);
2793 tree decl = build_decl (FUNCTION_DECL, id, type);
2794 TREE_PUBLIC (decl) = 1;
2795 DECL_EXTERNAL (decl) = 1;
2796 DECL_LANG_SPECIFIC (decl) = GGC_CNEW (struct lang_decl);
2797 DECL_BUILT_IN_CLASS (decl) = cl;
2798 DECL_FUNCTION_CODE (decl) = function_code;
2799 C_DECL_BUILTIN_PROTOTYPE (decl) = (TYPE_ARG_TYPES (type) != 0);
2801 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (library_name));
2803 /* Should never be called on a symbol with a preexisting meaning. */
2804 gcc_assert (!I_SYMBOL_BINDING (id));
2806 bind (id, decl, external_scope, /*invisible=*/true, /*nested=*/false);
2808 /* Builtins in the implementation namespace are made visible without
2809 needing to be explicitly declared. See push_file_scope. */
2810 if (name[0] == '_' && (name[1] == '_' || ISUPPER (name[1])))
2812 TREE_CHAIN (decl) = visible_builtins;
2813 visible_builtins = decl;
2816 /* Possibly apply some default attributes to this built-in function. */
2818 decl_attributes (&decl, attrs, ATTR_FLAG_BUILT_IN);
2820 decl_attributes (&decl, NULL_TREE, 0);
2825 /* Called when a declaration is seen that contains no names to declare.
2826 If its type is a reference to a structure, union or enum inherited
2827 from a containing scope, shadow that tag name for the current scope
2828 with a forward reference.
2829 If its type defines a new named structure or union
2830 or defines an enum, it is valid but we need not do anything here.
2831 Otherwise, it is an error. */
2834 shadow_tag (const struct c_declspecs *declspecs)
2836 shadow_tag_warned (declspecs, 0);
2839 /* WARNED is 1 if we have done a pedwarn, 2 if we have done a warning,
2842 shadow_tag_warned (const struct c_declspecs *declspecs, int warned)
2844 bool found_tag = false;
2846 if (declspecs->type && !declspecs->default_int_p && !declspecs->typedef_p)
2848 tree value = declspecs->type;
2849 enum tree_code code = TREE_CODE (value);
2851 if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
2852 /* Used to test also that TYPE_SIZE (value) != 0.
2853 That caused warning for `struct foo;' at top level in the file. */
2855 tree name = TYPE_NAME (value);
2862 if (warned != 1 && code != ENUMERAL_TYPE)
2863 /* Empty unnamed enum OK */
2865 pedwarn ("unnamed struct/union that defines no instances");
2869 else if (!declspecs->tag_defined_p
2870 && declspecs->storage_class != csc_none)
2873 pedwarn ("empty declaration with storage class specifier "
2874 "does not redeclare tag");
2876 pending_xref_error ();
2878 else if (!declspecs->tag_defined_p
2879 && (declspecs->const_p
2880 || declspecs->volatile_p
2881 || declspecs->restrict_p))
2884 pedwarn ("empty declaration with type qualifier "
2885 "does not redeclare tag");
2887 pending_xref_error ();
2891 pending_invalid_xref = 0;
2892 t = lookup_tag (code, name, 1);
2896 t = make_node (code);
2903 if (warned != 1 && !in_system_header)
2905 pedwarn ("useless type name in empty declaration");
2910 else if (warned != 1 && !in_system_header && declspecs->typedef_p)
2912 pedwarn ("useless type name in empty declaration");
2916 pending_invalid_xref = 0;
2918 if (declspecs->inline_p)
2920 error ("%<inline%> in empty declaration");
2924 if (current_scope == file_scope && declspecs->storage_class == csc_auto)
2926 error ("%<auto%> in file-scope empty declaration");
2930 if (current_scope == file_scope && declspecs->storage_class == csc_register)
2932 error ("%<register%> in file-scope empty declaration");
2936 if (!warned && !in_system_header && declspecs->storage_class != csc_none)
2938 warning (0, "useless storage class specifier in empty declaration");
2942 if (!warned && !in_system_header && declspecs->thread_p)
2944 warning (0, "useless %<__thread%> in empty declaration");
2948 if (!warned && !in_system_header && (declspecs->const_p
2949 || declspecs->volatile_p
2950 || declspecs->restrict_p))
2952 warning (0, "useless type qualifier in empty declaration");
2959 pedwarn ("empty declaration");
2964 /* Return the qualifiers from SPECS as a bitwise OR of TYPE_QUAL_*
2965 bits. SPECS represents declaration specifiers that the grammar
2966 only permits to contain type qualifiers and attributes. */
2969 quals_from_declspecs (const struct c_declspecs *specs)
2971 int quals = ((specs->const_p ? TYPE_QUAL_CONST : 0)
2972 | (specs->volatile_p ? TYPE_QUAL_VOLATILE : 0)
2973 | (specs->restrict_p ? TYPE_QUAL_RESTRICT : 0));
2974 gcc_assert (!specs->type
2975 && !specs->decl_attr
2976 && specs->typespec_word == cts_none
2977 && specs->storage_class == csc_none
2978 && !specs->typedef_p
2979 && !specs->explicit_signed_p
2980 && !specs->deprecated_p
2982 && !specs->long_long_p
2985 && !specs->unsigned_p
2986 && !specs->complex_p
2988 && !specs->thread_p);
2992 /* Construct an array declarator. EXPR is the expression inside [], or
2993 NULL_TREE. QUALS are the type qualifiers inside the [] (to be applied
2994 to the pointer to which a parameter array is converted). STATIC_P is
2995 true if "static" is inside the [], false otherwise. VLA_UNSPEC_P
2996 is true if the array is [*], a VLA of unspecified length which is
2997 nevertheless a complete type (not currently implemented by GCC),
2998 false otherwise. The field for the contained declarator is left to be
2999 filled in by set_array_declarator_inner. */
3001 struct c_declarator *
3002 build_array_declarator (tree expr, struct c_declspecs *quals, bool static_p,
3005 struct c_declarator *declarator = XOBNEW (&parser_obstack,
3006 struct c_declarator);
3007 declarator->kind = cdk_array;
3008 declarator->declarator = 0;
3009 declarator->u.array.dimen = expr;
3012 declarator->u.array.attrs = quals->attrs;
3013 declarator->u.array.quals = quals_from_declspecs (quals);
3017 declarator->u.array.attrs = NULL_TREE;
3018 declarator->u.array.quals = 0;
3020 declarator->u.array.static_p = static_p;
3021 declarator->u.array.vla_unspec_p = vla_unspec_p;
3022 if (pedantic && !flag_isoc99)
3024 if (static_p || quals != NULL)
3025 pedwarn ("ISO C90 does not support %<static%> or type "
3026 "qualifiers in parameter array declarators");
3028 pedwarn ("ISO C90 does not support %<[*]%> array declarators");
3031 warning (0, "GCC does not yet properly implement %<[*]%> array declarators");
3035 /* Set the contained declarator of an array declarator. DECL is the
3036 declarator, as constructed by build_array_declarator; INNER is what
3037 appears on the left of the []. ABSTRACT_P is true if it is an
3038 abstract declarator, false otherwise; this is used to reject static
3039 and type qualifiers in abstract declarators, where they are not in
3040 the C99 grammar (subject to possible change in DR#289). */
3042 struct c_declarator *
3043 set_array_declarator_inner (struct c_declarator *decl,
3044 struct c_declarator *inner, bool abstract_p)
3046 decl->declarator = inner;
3047 if (abstract_p && (decl->u.array.quals != TYPE_UNQUALIFIED
3048 || decl->u.array.attrs != NULL_TREE
3049 || decl->u.array.static_p))
3050 error ("static or type qualifiers in abstract declarator");
3054 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
3057 groktypename (struct c_type_name *type_name)
3060 tree attrs = type_name->specs->attrs;
3062 type_name->specs->attrs = NULL_TREE;
3064 type = grokdeclarator (type_name->declarator, type_name->specs, TYPENAME,
3067 /* Apply attributes. */
3068 decl_attributes (&type, attrs, 0);
3073 /* Decode a declarator in an ordinary declaration or data definition.
3074 This is called as soon as the type information and variable name
3075 have been parsed, before parsing the initializer if any.
3076 Here we create the ..._DECL node, fill in its type,
3077 and put it on the list of decls for the current context.
3078 The ..._DECL node is returned as the value.
3080 Exception: for arrays where the length is not specified,
3081 the type is left null, to be filled in by `finish_decl'.
3083 Function definitions do not come here; they go to start_function
3084 instead. However, external and forward declarations of functions
3085 do go through here. Structure field declarations are done by
3086 grokfield and not through here. */
3089 start_decl (struct c_declarator *declarator, struct c_declspecs *declspecs,
3090 bool initialized, tree attributes)
3095 /* An object declared as __attribute__((deprecated)) suppresses
3096 warnings of uses of other deprecated items. */
3097 if (lookup_attribute ("deprecated", attributes))
3098 deprecated_state = DEPRECATED_SUPPRESS;
3100 decl = grokdeclarator (declarator, declspecs,
3101 NORMAL, initialized, NULL);
3105 deprecated_state = DEPRECATED_NORMAL;
3107 if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
3108 && MAIN_NAME_P (DECL_NAME (decl)))
3109 warning (OPT_Wmain, "%q+D is usually a function", decl);
3112 /* Is it valid for this decl to have an initializer at all?
3113 If not, set INITIALIZED to zero, which will indirectly
3114 tell 'finish_decl' to ignore the initializer once it is parsed. */
3115 switch (TREE_CODE (decl))
3118 error ("typedef %qD is initialized (use __typeof__ instead)", decl);
3123 error ("function %qD is initialized like a variable", decl);
3128 /* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE. */
3129 error ("parameter %qD is initialized", decl);
3134 /* Don't allow initializations for incomplete types except for
3135 arrays which might be completed by the initialization. */
3137 /* This can happen if the array size is an undefined macro.
3138 We already gave a warning, so we don't need another one. */
3139 if (TREE_TYPE (decl) == error_mark_node)
3141 else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
3143 /* A complete type is ok if size is fixed. */
3145 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
3146 || C_DECL_VARIABLE_SIZE (decl))
3148 error ("variable-sized object may not be initialized");
3152 else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
3154 error ("variable %qD has initializer but incomplete type", decl);
3157 else if (C_DECL_VARIABLE_SIZE (decl))
3159 /* Although C99 is unclear about whether incomplete arrays
3160 of VLAs themselves count as VLAs, it does not make
3161 sense to permit them to be initialized given that
3162 ordinary VLAs may not be initialized. */
3163 error ("variable-sized object may not be initialized");
3170 if (current_scope == file_scope)
3171 TREE_STATIC (decl) = 1;
3173 /* Tell 'pushdecl' this is an initialized decl
3174 even though we don't yet have the initializer expression.
3175 Also tell 'finish_decl' it may store the real initializer. */
3176 DECL_INITIAL (decl) = error_mark_node;
3179 /* If this is a function declaration, write a record describing it to the
3180 prototypes file (if requested). */
3182 if (TREE_CODE (decl) == FUNCTION_DECL)
3183 gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);
3185 /* ANSI specifies that a tentative definition which is not merged with
3186 a non-tentative definition behaves exactly like a definition with an
3187 initializer equal to zero. (Section 3.7.2)
3189 -fno-common gives strict ANSI behavior, though this tends to break
3190 a large body of code that grew up without this rule.
3192 Thread-local variables are never common, since there's no entrenched
3193 body of code to break, and it allows more efficient variable references
3194 in the presence of dynamic linking. */
3196 if (TREE_CODE (decl) == VAR_DECL
3198 && TREE_PUBLIC (decl)
3199 && !DECL_THREAD_LOCAL_P (decl)
3201 DECL_COMMON (decl) = 1;
3203 /* Set attributes here so if duplicate decl, will have proper attributes. */
3204 decl_attributes (&decl, attributes, 0);
3206 if (TREE_CODE (decl) == FUNCTION_DECL
3207 && targetm.calls.promote_prototypes (TREE_TYPE (decl)))
3209 struct c_declarator *ce = declarator;
3211 if (ce->kind == cdk_pointer)
3212 ce = declarator->declarator;
3213 if (ce->kind == cdk_function)
3215 tree args = ce->u.arg_info->parms;
3216 for (; args; args = TREE_CHAIN (args))
3218 tree type = TREE_TYPE (args);
3219 if (type && INTEGRAL_TYPE_P (type)
3220 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
3221 DECL_ARG_TYPE (args) = integer_type_node;
3226 if (TREE_CODE (decl) == FUNCTION_DECL
3227 && DECL_DECLARED_INLINE_P (decl)
3228 && DECL_UNINLINABLE (decl)
3229 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
3230 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
3233 /* Add this decl to the current scope.
3234 TEM may equal DECL or it may be a previous decl of the same name. */
3235 tem = pushdecl (decl);
3237 if (initialized && DECL_EXTERNAL (tem))
3239 DECL_EXTERNAL (tem) = 0;
3240 TREE_STATIC (tem) = 1;
3246 /* Finish processing of a declaration;
3247 install its initial value.
3248 If the length of an array type is not known before,
3249 it must be determined now, from the initial value, or it is an error. */
3252 finish_decl (tree decl, tree init, tree asmspec_tree)
3254 tree type = TREE_TYPE (decl);
3255 int was_incomplete = (DECL_SIZE (decl) == 0);
3256 const char *asmspec = 0;
3258 /* If a name was specified, get the string. */
3259 if ((TREE_CODE (decl) == FUNCTION_DECL || TREE_CODE (decl) == VAR_DECL)
3260 && DECL_FILE_SCOPE_P (decl))
3261 asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
3263 asmspec = TREE_STRING_POINTER (asmspec_tree);
3265 /* If `start_decl' didn't like having an initialization, ignore it now. */
3266 if (init != 0 && DECL_INITIAL (decl) == 0)
3269 /* Don't crash if parm is initialized. */
3270 if (TREE_CODE (decl) == PARM_DECL)
3274 store_init_value (decl, init);
3276 if (c_dialect_objc () && (TREE_CODE (decl) == VAR_DECL
3277 || TREE_CODE (decl) == FUNCTION_DECL
3278 || TREE_CODE (decl) == FIELD_DECL))
3279 objc_check_decl (decl);
3281 /* Deduce size of array from initialization, if not already known. */
3282 if (TREE_CODE (type) == ARRAY_TYPE
3283 && TYPE_DOMAIN (type) == 0
3284 && TREE_CODE (decl) != TYPE_DECL)
3287 = (TREE_STATIC (decl)
3288 /* Even if pedantic, an external linkage array
3289 may have incomplete type at first. */
3290 ? pedantic && !TREE_PUBLIC (decl)
3291 : !DECL_EXTERNAL (decl));
3293 = complete_array_type (&TREE_TYPE (decl), DECL_INITIAL (decl),
3296 /* Get the completed type made by complete_array_type. */
3297 type = TREE_TYPE (decl);
3302 error ("initializer fails to determine size of %q+D", decl);
3307 error ("array size missing in %q+D", decl);
3308 /* If a `static' var's size isn't known,
3309 make it extern as well as static, so it does not get
3311 If it is not `static', then do not mark extern;
3312 finish_incomplete_decl will give it a default size
3313 and it will get allocated. */
3314 else if (!pedantic && TREE_STATIC (decl) && !TREE_PUBLIC (decl))
3315 DECL_EXTERNAL (decl) = 1;
3319 error ("zero or negative size array %q+D", decl);
3323 /* For global variables, update the copy of the type that
3324 exists in the binding. */
3325 if (TREE_PUBLIC (decl))
3327 struct c_binding *b_ext = I_SYMBOL_BINDING (DECL_NAME (decl));
3328 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
3329 b_ext = b_ext->shadowed;
3333 b_ext->type = composite_type (b_ext->type, type);
3344 if (DECL_INITIAL (decl))
3345 TREE_TYPE (DECL_INITIAL (decl)) = type;
3347 layout_decl (decl, 0);
3350 if (TREE_CODE (decl) == VAR_DECL)
3352 if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
3353 && COMPLETE_TYPE_P (TREE_TYPE (decl)))
3354 layout_decl (decl, 0);
3356 if (DECL_SIZE (decl) == 0
3357 /* Don't give an error if we already gave one earlier. */
3358 && TREE_TYPE (decl) != error_mark_node
3359 && (TREE_STATIC (decl)
3360 /* A static variable with an incomplete type
3361 is an error if it is initialized.
3362 Also if it is not file scope.
3363 Otherwise, let it through, but if it is not `extern'
3364 then it may cause an error message later. */
3365 ? (DECL_INITIAL (decl) != 0
3366 || !DECL_FILE_SCOPE_P (decl))
3367 /* An automatic variable with an incomplete type
3369 : !DECL_EXTERNAL (decl)))
3371 error ("storage size of %q+D isn%'t known", decl);
3372 TREE_TYPE (decl) = error_mark_node;
3375 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
3376 && DECL_SIZE (decl) != 0)
3378 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
3379 constant_expression_warning (DECL_SIZE (decl));
3381 error ("storage size of %q+D isn%'t constant", decl);
3384 if (TREE_USED (type))
3385 TREE_USED (decl) = 1;
3388 /* If this is a function and an assembler name is specified, reset DECL_RTL
3389 so we can give it its new name. Also, update built_in_decls if it
3390 was a normal built-in. */
3391 if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
3393 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
3394 set_builtin_user_assembler_name (decl, asmspec);
3395 set_user_assembler_name (decl, asmspec);
3398 /* If #pragma weak was used, mark the decl weak now. */
3399 maybe_apply_pragma_weak (decl);
3401 /* If this is a variable definition, determine its ELF visibility. */
3402 if (TREE_CODE (decl) == VAR_DECL
3403 && TREE_STATIC (decl)
3404 && !DECL_EXTERNAL (decl))
3405 c_determine_visibility (decl);
3407 /* Output the assembler code and/or RTL code for variables and functions,
3408 unless the type is an undefined structure or union.
3409 If not, it will get done when the type is completed. */
3411 if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
3413 /* This is a no-op in c-lang.c or something real in objc-act.c. */
3414 if (c_dialect_objc ())
3415 objc_check_decl (decl);
3419 /* If this is not a static variable, issue a warning.
3420 It doesn't make any sense to give an ASMSPEC for an
3421 ordinary, non-register local variable. Historically,
3422 GCC has accepted -- but ignored -- the ASMSPEC in
3424 if (!DECL_FILE_SCOPE_P (decl)
3425 && TREE_CODE (decl) == VAR_DECL
3426 && !C_DECL_REGISTER (decl)
3427 && !TREE_STATIC (decl))
3428 warning (0, "ignoring asm-specifier for non-static local "
3429 "variable %q+D", decl);
3430 else if (C_DECL_REGISTER (decl))
3431 change_decl_assembler_name (decl, get_identifier (asmspec));
3433 set_user_assembler_name (decl, asmspec);
3436 if (DECL_FILE_SCOPE_P (decl))
3438 if (DECL_INITIAL (decl) == NULL_TREE
3439 || DECL_INITIAL (decl) == error_mark_node)
3440 /* Don't output anything
3441 when a tentative file-scope definition is seen.
3442 But at end of compilation, do output code for them. */
3443 DECL_DEFER_OUTPUT (decl) = 1;
3444 rest_of_decl_compilation (decl, true, 0);
3448 /* In conjunction with an ASMSPEC, the `register'
3449 keyword indicates that we should place the variable
3450 in a particular register. */
3451 if (asmspec && C_DECL_REGISTER (decl))
3453 DECL_HARD_REGISTER (decl) = 1;
3454 /* This cannot be done for a structure with volatile
3455 fields, on which DECL_REGISTER will have been
3457 if (!DECL_REGISTER (decl))
3458 error ("cannot put object with volatile field into register");
3461 if (TREE_CODE (decl) != FUNCTION_DECL)
3463 /* If we're building a variable sized type, and we might be
3464 reachable other than via the top of the current binding
3465 level, then create a new BIND_EXPR so that we deallocate
3466 the object at the right time. */
3467 /* Note that DECL_SIZE can be null due to errors. */
3468 if (DECL_SIZE (decl)
3469 && !TREE_CONSTANT (DECL_SIZE (decl))
3470 && STATEMENT_LIST_HAS_LABEL (cur_stmt_list))
3473 bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL);
3474 TREE_SIDE_EFFECTS (bind) = 1;
3476 BIND_EXPR_BODY (bind) = push_stmt_list ();
3478 add_stmt (build_stmt (DECL_EXPR, decl));
3483 if (!DECL_FILE_SCOPE_P (decl))
3485 /* Recompute the RTL of a local array now
3486 if it used to be an incomplete type. */
3488 && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl))
3490 /* If we used it already as memory, it must stay in memory. */
3491 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
3492 /* If it's still incomplete now, no init will save it. */
3493 if (DECL_SIZE (decl) == 0)
3494 DECL_INITIAL (decl) = 0;
3499 /* If this was marked 'used', be sure it will be output. */
3500 if (lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
3501 mark_decl_referenced (decl);
3503 if (TREE_CODE (decl) == TYPE_DECL)
3505 if (!DECL_FILE_SCOPE_P (decl)
3506 && variably_modified_type_p (TREE_TYPE (decl), NULL_TREE))
3507 add_stmt (build_stmt (DECL_EXPR, decl));
3509 rest_of_decl_compilation (decl, DECL_FILE_SCOPE_P (decl), 0);
3512 /* At the end of a declaration, throw away any variable type sizes
3513 of types defined inside that declaration. There is no use
3514 computing them in the following function definition. */
3515 if (current_scope == file_scope)
3516 get_pending_sizes ();
3518 /* Install a cleanup (aka destructor) if one was given. */
3519 if (TREE_CODE (decl) == VAR_DECL && !TREE_STATIC (decl))
3521 tree attr = lookup_attribute ("cleanup", DECL_ATTRIBUTES (decl));
3524 tree cleanup_id = TREE_VALUE (TREE_VALUE (attr));
3525 tree cleanup_decl = lookup_name (cleanup_id);
3528 /* Build "cleanup(&decl)" for the destructor. */
3529 cleanup = build_unary_op (ADDR_EXPR, decl, 0);
3530 cleanup = build_tree_list (NULL_TREE, cleanup);
3531 cleanup = build_function_call (cleanup_decl, cleanup);
3533 /* Don't warn about decl unused; the cleanup uses it. */
3534 TREE_USED (decl) = 1;
3535 TREE_USED (cleanup_decl) = 1;
3537 /* Initialize EH, if we've been told to do so. */
3538 if (flag_exceptions && !c_eh_initialized_p)
3540 c_eh_initialized_p = true;
3541 eh_personality_libfunc
3542 = init_one_libfunc (USING_SJLJ_EXCEPTIONS
3543 ? "__gcc_personality_sj0"
3544 : "__gcc_personality_v0");
3545 default_init_unwind_resume_libfunc ();
3546 using_eh_for_cleanups ();
3549 push_cleanup (decl, cleanup, false);
3554 /* Given a parsed parameter declaration, decode it into a PARM_DECL. */
3557 grokparm (const struct c_parm *parm)
3559 tree decl = grokdeclarator (parm->declarator, parm->specs, PARM, false,
3562 decl_attributes (&decl, parm->attrs, 0);
3567 /* Given a parsed parameter declaration, decode it into a PARM_DECL
3568 and push that on the current scope. */
3571 push_parm_decl (const struct c_parm *parm)
3575 decl = grokdeclarator (parm->declarator, parm->specs, PARM, false, NULL);
3576 decl_attributes (&decl, parm->attrs, 0);
3578 decl = pushdecl (decl);
3580 finish_decl (decl, NULL_TREE, NULL_TREE);
3583 /* Mark all the parameter declarations to date as forward decls.
3584 Also diagnose use of this extension. */
3587 mark_forward_parm_decls (void)
3589 struct c_binding *b;
3591 if (pedantic && !current_scope->warned_forward_parm_decls)
3593 pedwarn ("ISO C forbids forward parameter declarations");
3594 current_scope->warned_forward_parm_decls = true;
3597 for (b = current_scope->bindings; b; b = b->prev)
3598 if (TREE_CODE (b->decl) == PARM_DECL)
3599 TREE_ASM_WRITTEN (b->decl) = 1;
3602 static GTY(()) int compound_literal_number;
3604 /* Build a COMPOUND_LITERAL_EXPR. TYPE is the type given in the compound
3605 literal, which may be an incomplete array type completed by the
3606 initializer; INIT is a CONSTRUCTOR that initializes the compound
3610 build_compound_literal (tree type, tree init)
3612 /* We do not use start_decl here because we have a type, not a declarator;
3613 and do not use finish_decl because the decl should be stored inside
3614 the COMPOUND_LITERAL_EXPR rather than added elsewhere as a DECL_EXPR. */
3619 if (type == error_mark_node)
3620 return error_mark_node;
3622 decl = build_decl (VAR_DECL, NULL_TREE, type);
3623 DECL_EXTERNAL (decl) = 0;
3624 TREE_PUBLIC (decl) = 0;
3625 TREE_STATIC (decl) = (current_scope == file_scope);
3626 DECL_CONTEXT (decl) = current_function_decl;
3627 TREE_USED (decl) = 1;
3628 TREE_TYPE (decl) = type;
3629 TREE_READONLY (decl) = TYPE_READONLY (type);
3630 store_init_value (decl, init);
3632 if (TREE_CODE (type) == ARRAY_TYPE && !COMPLETE_TYPE_P (type))
3634 int failure = complete_array_type (&TREE_TYPE (decl),
3635 DECL_INITIAL (decl), true);
3636 gcc_assert (!failure);
3638 type = TREE_TYPE (decl);
3639 TREE_TYPE (DECL_INITIAL (decl)) = type;
3642 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
3643 return error_mark_node;
3645 stmt = build_stmt (DECL_EXPR, decl);
3646 complit = build1 (COMPOUND_LITERAL_EXPR, type, stmt);
3647 TREE_SIDE_EFFECTS (complit) = 1;
3649 layout_decl (decl, 0);
3651 if (TREE_STATIC (decl))
3653 /* This decl needs a name for the assembler output. We also need
3654 a unique suffix to be added to the name. */
3657 ASM_FORMAT_PRIVATE_NAME (name, "__compound_literal",
3658 compound_literal_number);
3659 compound_literal_number++;
3660 DECL_NAME (decl) = get_identifier (name);
3661 DECL_DEFER_OUTPUT (decl) = 1;
3662 DECL_COMDAT (decl) = 1;
3663 DECL_ARTIFICIAL (decl) = 1;
3664 DECL_IGNORED_P (decl) = 1;
3666 rest_of_decl_compilation (decl, 1, 0);
3672 /* Determine whether TYPE is a structure with a flexible array member,
3673 or a union containing such a structure (possibly recursively). */
3676 flexible_array_type_p (tree type)
3679 switch (TREE_CODE (type))
3682 x = TYPE_FIELDS (type);
3685 while (TREE_CHAIN (x) != NULL_TREE)
3687 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
3688 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
3689 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
3690 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
3694 for (x = TYPE_FIELDS (type); x != NULL_TREE; x = TREE_CHAIN (x))
3696 if (flexible_array_type_p (TREE_TYPE (x)))
3705 /* Performs sanity checks on the TYPE and WIDTH of the bit-field NAME,
3706 replacing with appropriate values if they are invalid. */
3708 check_bitfield_type_and_width (tree *type, tree *width, const char *orig_name)
3711 unsigned int max_width;
3712 unsigned HOST_WIDE_INT w;
3713 const char *name = orig_name ? orig_name: _("<anonymous>");
3715 /* Detect and ignore out of range field width and process valid
3717 if (!INTEGRAL_TYPE_P (TREE_TYPE (*width))
3718 || TREE_CODE (*width) != INTEGER_CST)
3720 error ("bit-field %qs width not an integer constant", name);
3721 *width = integer_one_node;
3725 constant_expression_warning (*width);
3726 if (tree_int_cst_sgn (*width) < 0)
3728 error ("negative width in bit-field %qs", name);
3729 *width = integer_one_node;
3731 else if (integer_zerop (*width) && orig_name)
3733 error ("zero width for bit-field %qs", name);
3734 *width = integer_one_node;
3738 /* Detect invalid bit-field type. */
3739 if (TREE_CODE (*type) != INTEGER_TYPE
3740 && TREE_CODE (*type) != BOOLEAN_TYPE
3741 && TREE_CODE (*type) != ENUMERAL_TYPE)
3743 error ("bit-field %qs has invalid type", name);
3744 *type = unsigned_type_node;
3747 type_mv = TYPE_MAIN_VARIANT (*type);
3749 && type_mv != integer_type_node
3750 && type_mv != unsigned_type_node
3751 && type_mv != boolean_type_node)
3752 pedwarn ("type of bit-field %qs is a GCC extension", name);
3754 if (type_mv == boolean_type_node)
3755 max_width = CHAR_TYPE_SIZE;
3757 max_width = TYPE_PRECISION (*type);
3759 if (0 < compare_tree_int (*width, max_width))
3761 error ("width of %qs exceeds its type", name);
3763 *width = build_int_cst (NULL_TREE, w);
3766 w = tree_low_cst (*width, 1);
3768 if (TREE_CODE (*type) == ENUMERAL_TYPE)
3770 struct lang_type *lt = TYPE_LANG_SPECIFIC (*type);
3772 || w < min_precision (lt->enum_min, TYPE_UNSIGNED (*type))
3773 || w < min_precision (lt->enum_max, TYPE_UNSIGNED (*type)))
3774 warning (0, "%qs is narrower than values of its type", name);
3778 /* Given declspecs and a declarator,
3779 determine the name and type of the object declared
3780 and construct a ..._DECL node for it.
3781 (In one case we can return a ..._TYPE node instead.
3782 For invalid input we sometimes return 0.)
3784 DECLSPECS is a c_declspecs structure for the declaration specifiers.
3786 DECL_CONTEXT says which syntactic context this declaration is in:
3787 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
3788 FUNCDEF for a function definition. Like NORMAL but a few different
3789 error messages in each case. Return value may be zero meaning
3790 this definition is too screwy to try to parse.
3791 PARM for a parameter declaration (either within a function prototype
3792 or before a function body). Make a PARM_DECL, or return void_type_node.
3793 TYPENAME if for a typename (in a cast or sizeof).
3794 Don't make a DECL node; just return the ..._TYPE node.
3795 FIELD for a struct or union field; make a FIELD_DECL.
3796 INITIALIZED is true if the decl has an initializer.
3797 WIDTH is non-NULL for bit-fields, and is a pointer to an INTEGER_CST node
3798 representing the width of the bit-field.
3800 In the TYPENAME case, DECLARATOR is really an absolute declarator.
3801 It may also be so in the PARM case, for a prototype where the
3802 argument type is specified but not the name.
3804 This function is where the complicated C meanings of `static'
3805 and `extern' are interpreted. */
3808 grokdeclarator (const struct c_declarator *declarator,
3809 struct c_declspecs *declspecs,
3810 enum decl_context decl_context, bool initialized, tree *width)
3812 tree type = declspecs->type;
3813 bool threadp = declspecs->thread_p;
3814 enum c_storage_class storage_class = declspecs->storage_class;
3818 int type_quals = TYPE_UNQUALIFIED;
3819 const char *name, *orig_name;
3820 tree typedef_type = 0;
3821 int funcdef_flag = 0;
3822 bool funcdef_syntax = false;
3823 int size_varies = 0;
3824 tree decl_attr = declspecs->decl_attr;
3825 int array_ptr_quals = TYPE_UNQUALIFIED;
3826 tree array_ptr_attrs = NULL_TREE;
3827 int array_parm_static = 0;
3828 tree returned_attrs = NULL_TREE;
3829 bool bitfield = width != NULL;
3831 struct c_arg_info *arg_info = 0;
3833 if (decl_context == FUNCDEF)
3834 funcdef_flag = 1, decl_context = NORMAL;
3836 /* Look inside a declarator for the name being declared
3837 and get it as a string, for an error message. */
3839 const struct c_declarator *decl = declarator;
3848 funcdef_syntax = (decl->kind == cdk_function);
3849 decl = decl->declarator;
3853 decl = decl->declarator;
3858 name = IDENTIFIER_POINTER (decl->u.id);
3870 /* A function definition's declarator must have the form of
3871 a function declarator. */
3873 if (funcdef_flag && !funcdef_syntax)
3876 /* If this looks like a function definition, make it one,
3877 even if it occurs where parms are expected.
3878 Then store_parm_decls will reject it and not use it as a parm. */
3879 if (decl_context == NORMAL && !funcdef_flag && current_scope->parm_flag)
3880 decl_context = PARM;
3882 if (declspecs->deprecated_p && deprecated_state != DEPRECATED_SUPPRESS)
3883 warn_deprecated_use (declspecs->type);
3885 typedef_type = type;
3886 size_varies = C_TYPE_VARIABLE_SIZE (type);
3888 /* Diagnose defaulting to "int". */
3890 if (declspecs->default_int_p && !in_system_header)
3892 /* Issue a warning if this is an ISO C 99 program or if
3893 -Wreturn-type and this is a function, or if -Wimplicit;
3894 prefer the former warning since it is more explicit. */
3895 if ((warn_implicit_int || warn_return_type || flag_isoc99)
3897 warn_about_return_type = 1;
3898 else if (warn_implicit_int || flag_isoc99)
3899 pedwarn_c99 ("type defaults to %<int%> in declaration of %qs", name);
3902 /* Adjust the type if a bit-field is being declared,
3903 -funsigned-bitfields applied and the type is not explicitly
3905 if (bitfield && !flag_signed_bitfields && !declspecs->explicit_signed_p
3906 && TREE_CODE (type) == INTEGER_TYPE)
3907 type = c_common_unsigned_type (type);
3909 /* Figure out the type qualifiers for the declaration. There are
3910 two ways a declaration can become qualified. One is something
3911 like `const int i' where the `const' is explicit. Another is
3912 something like `typedef const int CI; CI i' where the type of the
3913 declaration contains the `const'. A third possibility is that
3914 there is a type qualifier on the element type of a typedefed
3915 array type, in which case we should extract that qualifier so
3916 that c_apply_type_quals_to_decls receives the full list of
3917 qualifiers to work with (C90 is not entirely clear about whether
3918 duplicate qualifiers should be diagnosed in this case, but it
3919 seems most appropriate to do so). */
3920 element_type = strip_array_types (type);
3921 constp = declspecs->const_p + TYPE_READONLY (element_type);
3922 restrictp = declspecs->restrict_p + TYPE_RESTRICT (element_type);
3923 volatilep = declspecs->volatile_p + TYPE_VOLATILE (element_type);
3924 if (pedantic && !flag_isoc99)
3927 pedwarn ("duplicate %<const%>");
3929 pedwarn ("duplicate %<restrict%>");
3931 pedwarn ("duplicate %<volatile%>");
3933 if (!flag_gen_aux_info && (TYPE_QUALS (element_type)))
3934 type = TYPE_MAIN_VARIANT (type);
3935 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
3936 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
3937 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
3939 /* Warn about storage classes that are invalid for certain
3940 kinds of declarations (parameters, typenames, etc.). */
3944 || storage_class == csc_auto
3945 || storage_class == csc_register
3946 || storage_class == csc_typedef))
3948 if (storage_class == csc_auto
3949 && (pedantic || current_scope == file_scope))
3950 pedwarn ("function definition declared %<auto%>");
3951 if (storage_class == csc_register)
3952 error ("function definition declared %<register%>");
3953 if (storage_class == csc_typedef)
3954 error ("function definition declared %<typedef%>");
3956 error ("function definition declared %<__thread%>");
3958 if (storage_class == csc_auto
3959 || storage_class == csc_register
3960 || storage_class == csc_typedef)
3961 storage_class = csc_none;
3963 else if (decl_context != NORMAL && (storage_class != csc_none || threadp))
3965 if (decl_context == PARM && storage_class == csc_register)
3969 switch (decl_context)
3972 error ("storage class specified for structure field %qs",
3976 error ("storage class specified for parameter %qs", name);
3979 error ("storage class specified for typename");
3982 storage_class = csc_none;
3986 else if (storage_class == csc_extern
3990 /* 'extern' with initialization is invalid if not at file scope. */
3991 if (current_scope == file_scope)
3992 warning (0, "%qs initialized and declared %<extern%>", name);
3994 error ("%qs has both %<extern%> and initializer", name);
3996 else if (current_scope == file_scope)
3998 if (storage_class == csc_auto)
3999 error ("file-scope declaration of %qs specifies %<auto%>", name);
4000 if (pedantic && storage_class == csc_register)
4001 pedwarn ("file-scope declaration of %qs specifies %<register%>", name);
4005 if (storage_class == csc_extern && funcdef_flag)
4006 error ("nested function %qs declared %<extern%>", name);
4007 else if (threadp && storage_class == csc_none)
4009 error ("function-scope %qs implicitly auto and declared "
4016 /* Now figure out the structure of the declarator proper.
4017 Descend through it, creating more complex types, until we reach
4018 the declared identifier (or NULL_TREE, in an absolute declarator).
4019 At each stage we maintain an unqualified version of the type
4020 together with any qualifiers that should be applied to it with
4021 c_build_qualified_type; this way, array types including
4022 multidimensional array types are first built up in unqualified
4023 form and then the qualified form is created with
4024 TYPE_MAIN_VARIANT pointing to the unqualified form. */
4026 while (declarator && declarator->kind != cdk_id)
4028 if (type == error_mark_node)
4030 declarator = declarator->declarator;
4034 /* Each level of DECLARATOR is either a cdk_array (for ...[..]),
4035 a cdk_pointer (for *...),
4036 a cdk_function (for ...(...)),
4037 a cdk_attrs (for nested attributes),
4038 or a cdk_id (for the name being declared
4039 or the place in an absolute declarator
4040 where the name was omitted).
4041 For the last case, we have just exited the loop.
4043 At this point, TYPE is the type of elements of an array,
4044 or for a function to return, or for a pointer to point to.
4045 After this sequence of ifs, TYPE is the type of the
4046 array or function or pointer, and DECLARATOR has had its
4047 outermost layer removed. */
4049 if (array_ptr_quals != TYPE_UNQUALIFIED
4050 || array_ptr_attrs != NULL_TREE
4051 || array_parm_static)
4053 /* Only the innermost declarator (making a parameter be of
4054 array type which is converted to pointer type)
4055 may have static or type qualifiers. */
4056 error ("static or type qualifiers in non-parameter array declarator");
4057 array_ptr_quals = TYPE_UNQUALIFIED;
4058 array_ptr_attrs = NULL_TREE;
4059 array_parm_static = 0;
4062 switch (declarator->kind)
4066 /* A declarator with embedded attributes. */
4067 tree attrs = declarator->u.attrs;
4068 const struct c_declarator *inner_decl;
4070 declarator = declarator->declarator;
4071 inner_decl = declarator;
4072 while (inner_decl->kind == cdk_attrs)
4073 inner_decl = inner_decl->declarator;
4074 if (inner_decl->kind == cdk_id)
4075 attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
4076 else if (inner_decl->kind == cdk_function)
4077 attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
4078 else if (inner_decl->kind == cdk_array)
4079 attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
4080 returned_attrs = decl_attributes (&type,
4081 chainon (returned_attrs, attrs),
4087 tree itype = NULL_TREE;
4088 tree size = declarator->u.array.dimen;
4089 /* The index is a signed object `sizetype' bits wide. */
4090 tree index_type = c_common_signed_type (sizetype);
4092 array_ptr_quals = declarator->u.array.quals;
4093 array_ptr_attrs = declarator->u.array.attrs;
4094 array_parm_static = declarator->u.array.static_p;
4096 declarator = declarator->declarator;
4098 /* Check for some types that there cannot be arrays of. */
4100 if (VOID_TYPE_P (type))
4102 error ("declaration of %qs as array of voids", name);
4103 type = error_mark_node;
4106 if (TREE_CODE (type) == FUNCTION_TYPE)
4108 error ("declaration of %qs as array of functions", name);
4109 type = error_mark_node;
4112 if (pedantic && !in_system_header && flexible_array_type_p (type))
4113 pedwarn ("invalid use of structure with flexible array member");
4115 if (size == error_mark_node)
4116 type = error_mark_node;
4118 if (type == error_mark_node)
4121 /* If size was specified, set ITYPE to a range-type for
4122 that size. Otherwise, ITYPE remains null. finish_decl
4123 may figure it out from an initial value. */
4127 /* Strip NON_LVALUE_EXPRs since we aren't using as an
4129 STRIP_TYPE_NOPS (size);
4131 if (!INTEGRAL_TYPE_P (TREE_TYPE (size)))
4133 error ("size of array %qs has non-integer type", name);
4134 size = integer_one_node;
4137 if (pedantic && integer_zerop (size))
4138 pedwarn ("ISO C forbids zero-size array %qs", name);
4140 if (TREE_CODE (size) == INTEGER_CST)
4142 constant_expression_warning (size);
4143 if (tree_int_cst_sgn (size) < 0)
4145 error ("size of array %qs is negative", name);
4146 size = integer_one_node;
4151 /* Make sure the array size remains visibly
4152 nonconstant even if it is (eg) a const variable
4153 with known value. */
4156 if (!flag_isoc99 && pedantic)
4158 if (TREE_CONSTANT (size))
4159 pedwarn ("ISO C90 forbids array %qs whose size "
4160 "can%'t be evaluated",
4163 pedwarn ("ISO C90 forbids variable-size array %qs",
4168 if (integer_zerop (size))
4170 /* A zero-length array cannot be represented with
4171 an unsigned index type, which is what we'll
4172 get with build_index_type. Create an
4173 open-ended range instead. */
4174 itype = build_range_type (sizetype, size, NULL_TREE);
4178 /* Arrange for the SAVE_EXPR on the inside of the
4179 MINUS_EXPR, which allows the -1 to get folded
4180 with the +1 that happens when building TYPE_SIZE. */
4182 size = variable_size (size);
4184 /* Compute the maximum valid index, that is, size
4185 - 1. Do the calculation in index_type, so that
4186 if it is a variable the computations will be
4187 done in the proper mode. */
4188 itype = fold_build2 (MINUS_EXPR, index_type,
4189 convert (index_type, size),
4190 convert (index_type,
4193 /* If that overflowed, the array is too big. ???
4194 While a size of INT_MAX+1 technically shouldn't
4195 cause an overflow (because we subtract 1), the
4196 overflow is recorded during the conversion to
4197 index_type, before the subtraction. Handling
4198 this case seems like an unnecessary
4200 if (TREE_CODE (itype) == INTEGER_CST
4201 && TREE_OVERFLOW (itype))
4203 error ("size of array %qs is too large", name);
4204 type = error_mark_node;
4208 itype = build_index_type (itype);
4211 else if (decl_context == FIELD)
4213 if (pedantic && !flag_isoc99 && !in_system_header)
4214 pedwarn ("ISO C90 does not support flexible array members");
4216 /* ISO C99 Flexible array members are effectively
4217 identical to GCC's zero-length array extension. */
4218 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4221 /* Complain about arrays of incomplete types. */
4222 if (!COMPLETE_TYPE_P (type))
4224 error ("array type has incomplete element type");
4225 type = error_mark_node;
4228 type = build_array_type (type, itype);
4231 C_TYPE_VARIABLE_SIZE (type) = 1;
4233 /* The GCC extension for zero-length arrays differs from
4234 ISO flexible array members in that sizeof yields
4236 if (size && integer_zerop (size))
4238 TYPE_SIZE (type) = bitsize_zero_node;
4239 TYPE_SIZE_UNIT (type) = size_zero_node;
4242 if (decl_context != PARM
4243 && (array_ptr_quals != TYPE_UNQUALIFIED
4244 || array_ptr_attrs != NULL_TREE
4245 || array_parm_static))
4247 error ("static or type qualifiers in non-parameter array declarator");
4248 array_ptr_quals = TYPE_UNQUALIFIED;
4249 array_ptr_attrs = NULL_TREE;
4250 array_parm_static = 0;
4256 /* Say it's a definition only for the declarator closest
4257 to the identifier, apart possibly from some
4259 bool really_funcdef = false;
4263 const struct c_declarator *t = declarator->declarator;
4264 while (t->kind == cdk_attrs)
4266 really_funcdef = (t->kind == cdk_id);
4269 /* Declaring a function type. Make sure we have a valid
4270 type for the function to return. */
4271 if (type == error_mark_node)
4276 /* Warn about some types functions can't return. */
4277 if (TREE_CODE (type) == FUNCTION_TYPE)
4279 error ("%qs declared as function returning a function", name);
4280 type = integer_type_node;
4282 if (TREE_CODE (type) == ARRAY_TYPE)
4284 error ("%qs declared as function returning an array", name);
4285 type = integer_type_node;
4288 /* Construct the function type and go to the next
4289 inner layer of declarator. */
4290 arg_info = declarator->u.arg_info;
4291 arg_types = grokparms (arg_info, really_funcdef);
4293 /* Type qualifiers before the return type of the function
4294 qualify the return type, not the function type. */
4297 /* Type qualifiers on a function return type are
4298 normally permitted by the standard but have no
4299 effect, so give a warning at -Wreturn-type.
4300 Qualifiers on a void return type are banned on
4301 function definitions in ISO C; GCC used to used
4302 them for noreturn functions. */
4303 if (VOID_TYPE_P (type) && really_funcdef)
4304 pedwarn ("function definition has qualified void return type");
4306 warning (OPT_Wreturn_type,
4307 "type qualifiers ignored on function return type");
4309 type = c_build_qualified_type (type, type_quals);
4311 type_quals = TYPE_UNQUALIFIED;
4313 type = build_function_type (type, arg_types);
4314 declarator = declarator->declarator;
4316 /* Set the TYPE_CONTEXTs for each tagged type which is local to
4317 the formal parameter list of this FUNCTION_TYPE to point to
4318 the FUNCTION_TYPE node itself. */
4322 for (link = arg_info->tags;
4324 link = TREE_CHAIN (link))
4325 TYPE_CONTEXT (TREE_VALUE (link)) = type;
4331 /* Merge any constancy or volatility into the target type
4334 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4336 pedwarn ("ISO C forbids qualified function types");
4338 type = c_build_qualified_type (type, type_quals);
4341 type = build_pointer_type (type);
4343 /* Process type qualifiers (such as const or volatile)
4344 that were given inside the `*'. */
4345 type_quals = declarator->u.pointer_quals;
4347 declarator = declarator->declarator;
4355 /* Now TYPE has the actual type, apart from any qualifiers in
4358 /* Check the type and width of a bit-field. */
4360 check_bitfield_type_and_width (&type, width, orig_name);
4362 /* Did array size calculations overflow? */
4364 if (TREE_CODE (type) == ARRAY_TYPE
4365 && COMPLETE_TYPE_P (type)
4366 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4367 && TREE_OVERFLOW (TYPE_SIZE (type)))
4369 error ("size of array %qs is too large", name);
4370 /* If we proceed with the array type as it is, we'll eventually
4371 crash in tree_low_cst(). */
4372 type = error_mark_node;
4375 /* If this is declaring a typedef name, return a TYPE_DECL. */
4377 if (storage_class == csc_typedef)
4380 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4382 pedwarn ("ISO C forbids qualified function types");
4384 type = c_build_qualified_type (type, type_quals);
4385 decl = build_decl (TYPE_DECL, declarator->u.id, type);
4386 if (declspecs->explicit_signed_p)
4387 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
4388 decl_attributes (&decl, returned_attrs, 0);
4389 if (declspecs->inline_p)
4390 pedwarn ("typedef %q+D declared %<inline%>", decl);
4394 /* Detect the case of an array type of unspecified size
4395 which came, as such, direct from a typedef name.
4396 We must copy the type, so that each identifier gets
4397 a distinct type, so that each identifier's size can be
4398 controlled separately by its own initializer. */
4400 if (type != 0 && typedef_type != 0
4401 && TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type) == 0
4402 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (typedef_type))
4404 type = build_array_type (TREE_TYPE (type), 0);
4406 C_TYPE_VARIABLE_SIZE (type) = 1;
4409 /* If this is a type name (such as, in a cast or sizeof),
4410 compute the type and return it now. */
4412 if (decl_context == TYPENAME)
4414 /* Note that the grammar rejects storage classes in typenames
4416 gcc_assert (storage_class == csc_none && !threadp
4417 && !declspecs->inline_p);
4418 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4420 pedwarn ("ISO C forbids const or volatile function types");
4422 type = c_build_qualified_type (type, type_quals);
4423 decl_attributes (&type, returned_attrs, 0);
4427 /* Aside from typedefs and type names (handle above),
4428 `void' at top level (not within pointer)
4429 is allowed only in public variables.
4430 We don't complain about parms either, but that is because
4431 a better error message can be made later. */
4433 if (VOID_TYPE_P (type) && decl_context != PARM
4434 && !((decl_context != FIELD && TREE_CODE (type) != FUNCTION_TYPE)
4435 && (storage_class == csc_extern
4436 || (current_scope == file_scope
4437 && !(storage_class == csc_static
4438 || storage_class == csc_register)))))
4440 error ("variable or field %qs declared void", name);
4441 type = integer_type_node;
4444 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
4445 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
4450 if (decl_context == PARM)
4452 tree type_as_written;
4455 /* A parameter declared as an array of T is really a pointer to T.
4456 One declared as a function is really a pointer to a function. */
4458 if (TREE_CODE (type) == ARRAY_TYPE)
4460 /* Transfer const-ness of array into that of type pointed to. */
4461 type = TREE_TYPE (type);
4463 type = c_build_qualified_type (type, type_quals);
4464 type = build_pointer_type (type);
4465 type_quals = array_ptr_quals;
4467 /* We don't yet implement attributes in this context. */
4468 if (array_ptr_attrs != NULL_TREE)
4469 warning (OPT_Wattributes,
4470 "attributes in parameter array declarator ignored");
4474 else if (TREE_CODE (type) == FUNCTION_TYPE)
4476 if (pedantic && type_quals)
4477 pedwarn ("ISO C forbids qualified function types");
4479 type = c_build_qualified_type (type, type_quals);
4480 type = build_pointer_type (type);
4481 type_quals = TYPE_UNQUALIFIED;
4483 else if (type_quals)
4484 type = c_build_qualified_type (type, type_quals);
4486 type_as_written = type;
4488 decl = build_decl (PARM_DECL, declarator->u.id, type);
4490 C_DECL_VARIABLE_SIZE (decl) = 1;
4492 /* Compute the type actually passed in the parmlist,
4493 for the case where there is no prototype.
4494 (For example, shorts and chars are passed as ints.)
4495 When there is a prototype, this is overridden later. */
4497 if (type == error_mark_node)
4498 promoted_type = type;
4500 promoted_type = c_type_promotes_to (type);
4502 DECL_ARG_TYPE (decl) = promoted_type;
4503 if (declspecs->inline_p)
4504 pedwarn ("parameter %q+D declared %<inline%>", decl);
4506 else if (decl_context == FIELD)
4508 /* Note that the grammar rejects storage classes in typenames
4510 gcc_assert (storage_class == csc_none && !threadp
4511 && !declspecs->inline_p);
4513 /* Structure field. It may not be a function. */
4515 if (TREE_CODE (type) == FUNCTION_TYPE)
4517 error ("field %qs declared as a function", name);
4518 type = build_pointer_type (type);
4520 else if (TREE_CODE (type) != ERROR_MARK
4521 && !COMPLETE_OR_UNBOUND_ARRAY_TYPE_P (type))
4523 error ("field %qs has incomplete type", name);
4524 type = error_mark_node;
4526 type = c_build_qualified_type (type, type_quals);
4527 decl = build_decl (FIELD_DECL, declarator->u.id, type);
4528 DECL_NONADDRESSABLE_P (decl) = bitfield;
4531 C_DECL_VARIABLE_SIZE (decl) = 1;
4533 else if (TREE_CODE (type) == FUNCTION_TYPE)
4535 if (storage_class == csc_register || threadp)
4537 error ("invalid storage class for function %qs", name);
4539 else if (current_scope != file_scope)
4541 /* Function declaration not at file scope. Storage
4542 classes other than `extern' are not allowed, C99
4543 6.7.1p5, and `extern' makes no difference. However,
4544 GCC allows 'auto', perhaps with 'inline', to support
4545 nested functions. */
4546 if (storage_class == csc_auto)
4549 pedwarn ("invalid storage class for function %qs", name);
4551 else if (storage_class == csc_static)
4553 error ("invalid storage class for function %qs", name);
4555 storage_class = declspecs->storage_class = csc_none;
4561 decl = build_decl (FUNCTION_DECL, declarator->u.id, type);
4562 decl = build_decl_attribute_variant (decl, decl_attr);
4564 DECL_LANG_SPECIFIC (decl) = GGC_CNEW (struct lang_decl);
4566 if (pedantic && type_quals && !DECL_IN_SYSTEM_HEADER (decl))
4567 pedwarn ("ISO C forbids qualified function types");
4569 /* GNU C interprets a volatile-qualified function type to indicate
4570 that the function does not return. */
4571 if ((type_quals & TYPE_QUAL_VOLATILE)
4572 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
4573 warning (0, "%<noreturn%> function returns non-void value");
4575 /* Every function declaration is an external reference
4576 (DECL_EXTERNAL) except for those which are not at file
4577 scope and are explicitly declared "auto". This is
4578 forbidden by standard C (C99 6.7.1p5) and is interpreted by
4579 GCC to signify a forward declaration of a nested function. */
4580 if (storage_class == csc_auto && current_scope != file_scope)
4581 DECL_EXTERNAL (decl) = 0;
4583 DECL_EXTERNAL (decl) = 1;
4585 /* Record absence of global scope for `static' or `auto'. */
4587 = !(storage_class == csc_static || storage_class == csc_auto);
4589 /* For a function definition, record the argument information
4590 block where store_parm_decls will look for it. */
4592 current_function_arg_info = arg_info;
4594 if (declspecs->default_int_p)
4595 C_FUNCTION_IMPLICIT_INT (decl) = 1;
4597 /* Record presence of `inline', if it is reasonable. */
4598 if (flag_hosted && MAIN_NAME_P (declarator->u.id))
4600 if (declspecs->inline_p)
4601 pedwarn ("cannot inline function %<main%>");
4603 else if (declspecs->inline_p)
4605 /* Record that the function is declared `inline'. */
4606 DECL_DECLARED_INLINE_P (decl) = 1;
4608 /* Do not mark bare declarations as DECL_INLINE. Doing so
4609 in the presence of multiple declarations can result in
4610 the abstract origin pointing between the declarations,
4611 which will confuse dwarf2out. */
4614 DECL_INLINE (decl) = 1;
4615 if (storage_class == csc_extern)
4616 current_extern_inline = 1;
4619 /* If -finline-functions, assume it can be inlined. This does
4620 two things: let the function be deferred until it is actually
4621 needed, and let dwarf2 know that the function is inlinable. */
4622 else if (flag_inline_trees == 2 && initialized)
4623 DECL_INLINE (decl) = 1;
4627 /* It's a variable. */
4628 /* An uninitialized decl with `extern' is a reference. */
4629 int extern_ref = !initialized && storage_class == csc_extern;
4631 type = c_build_qualified_type (type, type_quals);
4633 /* C99 6.2.2p7: It is invalid (compile-time undefined
4634 behavior) to create an 'extern' declaration for a
4635 variable if there is a global declaration that is
4636 'static' and the global declaration is not visible.
4637 (If the static declaration _is_ currently visible,
4638 the 'extern' declaration is taken to refer to that decl.) */
4639 if (extern_ref && current_scope != file_scope)
4641 tree global_decl = identifier_global_value (declarator->u.id);
4642 tree visible_decl = lookup_name (declarator->u.id);
4645 && global_decl != visible_decl
4646 && TREE_CODE (global_decl) == VAR_DECL
4647 && !TREE_PUBLIC (global_decl))
4648 error ("variable previously declared %<static%> redeclared "
4652 decl = build_decl (VAR_DECL, declarator->u.id, type);
4653 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
4655 C_DECL_VARIABLE_SIZE (decl) = 1;
4657 if (declspecs->inline_p)
4658 pedwarn ("variable %q+D declared %<inline%>", decl);
4660 /* At file scope, an initialized extern declaration may follow
4661 a static declaration. In that case, DECL_EXTERNAL will be
4662 reset later in start_decl. */
4663 DECL_EXTERNAL (decl) = (storage_class == csc_extern);
4665 /* At file scope, the presence of a `static' or `register' storage
4666 class specifier, or the absence of all storage class specifiers
4667 makes this declaration a definition (perhaps tentative). Also,
4668 the absence of both `static' and `register' makes it public. */
4669 if (current_scope == file_scope)
4671 TREE_PUBLIC (decl) = !(storage_class == csc_static
4672 || storage_class == csc_register);
4673 TREE_STATIC (decl) = !extern_ref;
4675 /* Not at file scope, only `static' makes a static definition. */
4678 TREE_STATIC (decl) = (storage_class == csc_static);
4679 TREE_PUBLIC (decl) = extern_ref;
4684 if (targetm.have_tls)
4685 DECL_TLS_MODEL (decl) = decl_default_tls_model (decl);
4687 /* A mere warning is sure to result in improper semantics
4688 at runtime. Don't bother to allow this to compile. */
4689 error ("thread-local storage not supported for this target");
4693 /* Record `register' declaration for warnings on &
4694 and in case doing stupid register allocation. */
4696 if (storage_class == csc_register)
4698 C_DECL_REGISTER (decl) = 1;
4699 DECL_REGISTER (decl) = 1;
4702 /* Record constancy and volatility. */
4703 c_apply_type_quals_to_decl (type_quals, decl);
4705 /* If a type has volatile components, it should be stored in memory.
4706 Otherwise, the fact that those components are volatile
4707 will be ignored, and would even crash the compiler.
4708 Of course, this only makes sense on VAR,PARM, and RESULT decl's. */
4709 if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (decl))
4710 && (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL
4711 || TREE_CODE (decl) == RESULT_DECL))
4713 /* It is not an error for a structure with volatile fields to
4714 be declared register, but reset DECL_REGISTER since it
4715 cannot actually go in a register. */
4716 int was_reg = C_DECL_REGISTER (decl);
4717 C_DECL_REGISTER (decl) = 0;
4718 DECL_REGISTER (decl) = 0;
4719 c_mark_addressable (decl);
4720 C_DECL_REGISTER (decl) = was_reg;
4723 /* This is the earliest point at which we might know the assembler
4724 name of a variable. Thus, if it's known before this, die horribly. */
4725 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl));
4727 decl_attributes (&decl, returned_attrs, 0);
4733 /* Decode the parameter-list info for a function type or function definition.
4734 The argument is the value returned by `get_parm_info' (or made in parse.y
4735 if there is an identifier list instead of a parameter decl list).
4736 These two functions are separate because when a function returns
4737 or receives functions then each is called multiple times but the order
4738 of calls is different. The last call to `grokparms' is always the one
4739 that contains the formal parameter names of a function definition.
4741 Return a list of arg types to use in the FUNCTION_TYPE for this function.
4743 FUNCDEF_FLAG is true for a function definition, false for
4744 a mere declaration. A nonempty identifier-list gets an error message
4745 when FUNCDEF_FLAG is false. */
4748 grokparms (struct c_arg_info *arg_info, bool funcdef_flag)
4750 tree arg_types = arg_info->types;
4752 if (arg_types == 0 && !funcdef_flag && !in_system_header)
4753 warning (OPT_Wstrict_prototypes,
4754 "function declaration isn%'t a prototype");
4756 if (arg_types == error_mark_node)
4757 return 0; /* don't set TYPE_ARG_TYPES in this case */
4759 else if (arg_types && TREE_CODE (TREE_VALUE (arg_types)) == IDENTIFIER_NODE)
4762 pedwarn ("parameter names (without types) in function declaration");
4764 arg_info->parms = arg_info->types;
4765 arg_info->types = 0;
4770 tree parm, type, typelt;
4771 unsigned int parmno;
4773 /* If there is a parameter of incomplete type in a definition,
4774 this is an error. In a declaration this is valid, and a
4775 struct or union type may be completed later, before any calls
4776 or definition of the function. In the case where the tag was
4777 first declared within the parameter list, a warning has
4778 already been given. If a parameter has void type, then
4779 however the function cannot be defined or called, so
4782 for (parm = arg_info->parms, typelt = arg_types, parmno = 1;
4784 parm = TREE_CHAIN (parm), typelt = TREE_CHAIN (typelt), parmno++)
4786 type = TREE_VALUE (typelt);
4787 if (type == error_mark_node)
4790 if (!COMPLETE_TYPE_P (type))
4794 if (DECL_NAME (parm))
4795 error ("parameter %u (%q+D) has incomplete type",
4798 error ("%Jparameter %u has incomplete type",
4801 TREE_VALUE (typelt) = error_mark_node;
4802 TREE_TYPE (parm) = error_mark_node;
4804 else if (VOID_TYPE_P (type))
4806 if (DECL_NAME (parm))
4807 warning (0, "parameter %u (%q+D) has void type",
4810 warning (0, "%Jparameter %u has void type",
4819 /* Take apart the current scope and return a c_arg_info structure with
4820 info on a parameter list just parsed.
4822 This structure is later fed to 'grokparms' and 'store_parm_decls'.
4824 ELLIPSIS being true means the argument list ended in '...' so don't
4825 append a sentinel (void_list_node) to the end of the type-list. */
4828 get_parm_info (bool ellipsis)
4830 struct c_binding *b = current_scope->bindings;
4831 struct c_arg_info *arg_info = XOBNEW (&parser_obstack,
4838 static bool explained_incomplete_types = false;
4839 bool gave_void_only_once_err = false;
4841 arg_info->parms = 0;
4843 arg_info->types = 0;
4844 arg_info->others = 0;
4846 /* The bindings in this scope must not get put into a block.
4847 We will take care of deleting the binding nodes. */
4848 current_scope->bindings = 0;
4850 /* This function is only called if there was *something* on the
4854 /* A parameter list consisting solely of 'void' indicates that the
4855 function takes no arguments. But if the 'void' is qualified
4856 (by 'const' or 'volatile'), or has a storage class specifier
4857 ('register'), then the behavior is undefined; issue an error.
4858 Typedefs for 'void' are OK (see DR#157). */
4859 if (b->prev == 0 /* one binding */
4860 && TREE_CODE (b->decl) == PARM_DECL /* which is a parameter */
4861 && !DECL_NAME (b->decl) /* anonymous */
4862 && VOID_TYPE_P (TREE_TYPE (b->decl))) /* of void type */
4864 if (TREE_THIS_VOLATILE (b->decl)
4865 || TREE_READONLY (b->decl)
4866 || C_DECL_REGISTER (b->decl))
4867 error ("%<void%> as only parameter may not be qualified");
4869 /* There cannot be an ellipsis. */
4871 error ("%<void%> must be the only parameter");
4873 arg_info->types = void_list_node;
4878 types = void_list_node;
4880 /* Break up the bindings list into parms, tags, types, and others;
4881 apply sanity checks; purge the name-to-decl bindings. */
4884 tree decl = b->decl;
4885 tree type = TREE_TYPE (decl);
4886 const char *keyword;
4888 switch (TREE_CODE (decl))
4893 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
4894 I_SYMBOL_BINDING (b->id) = b->shadowed;
4897 /* Check for forward decls that never got their actual decl. */
4898 if (TREE_ASM_WRITTEN (decl))
4899 error ("parameter %q+D has just a forward declaration", decl);
4900 /* Check for (..., void, ...) and issue an error. */
4901 else if (VOID_TYPE_P (type) && !DECL_NAME (decl))
4903 if (!gave_void_only_once_err)
4905 error ("%<void%> must be the only parameter");
4906 gave_void_only_once_err = true;
4911 /* Valid parameter, add it to the list. */
4912 TREE_CHAIN (decl) = parms;
4915 /* Since there is a prototype, args are passed in their
4916 declared types. The back end may override this later. */
4917 DECL_ARG_TYPE (decl) = type;
4918 types = tree_cons (0, type, types);
4922 case ENUMERAL_TYPE: keyword = "enum"; goto tag;
4923 case UNION_TYPE: keyword = "union"; goto tag;
4924 case RECORD_TYPE: keyword = "struct"; goto tag;
4926 /* Types may not have tag-names, in which case the type
4927 appears in the bindings list with b->id NULL. */
4930 gcc_assert (I_TAG_BINDING (b->id) == b);
4931 I_TAG_BINDING (b->id) = b->shadowed;
4934 /* Warn about any struct, union or enum tags defined in a
4935 parameter list. The scope of such types is limited to
4936 the parameter list, which is rarely if ever desirable
4937 (it's impossible to call such a function with type-
4938 correct arguments). An anonymous union parm type is
4939 meaningful as a GNU extension, so don't warn for that. */
4940 if (TREE_CODE (decl) != UNION_TYPE || b->id != 0)
4943 /* The %s will be one of 'struct', 'union', or 'enum'. */
4944 warning (0, "%<%s %E%> declared inside parameter list",
4947 /* The %s will be one of 'struct', 'union', or 'enum'. */
4948 warning (0, "anonymous %s declared inside parameter list",
4951 if (!explained_incomplete_types)
4953 warning (0, "its scope is only this definition or declaration,"
4954 " which is probably not what you want");
4955 explained_incomplete_types = true;
4959 tags = tree_cons (b->id, decl, tags);
4965 /* CONST_DECLs appear here when we have an embedded enum,
4966 and TYPE_DECLs appear here when we have an embedded struct
4967 or union. No warnings for this - we already warned about the
4968 type itself. FUNCTION_DECLs appear when there is an implicit
4969 function declaration in the parameter list. */
4971 TREE_CHAIN (decl) = others;
4976 /* error_mark_node appears here when we have an undeclared
4977 variable. Just throw it away. */
4980 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
4981 I_SYMBOL_BINDING (b->id) = b->shadowed;
4985 /* Other things that might be encountered. */
4992 b = free_binding_and_advance (b);
4995 arg_info->parms = parms;
4996 arg_info->tags = tags;
4997 arg_info->types = types;
4998 arg_info->others = others;
5002 /* Get the struct, enum or union (CODE says which) with tag NAME.
5003 Define the tag as a forward-reference if it is not defined.
5004 Return a c_typespec structure for the type specifier. */
5007 parser_xref_tag (enum tree_code code, tree name)
5009 struct c_typespec ret;
5010 /* If a cross reference is requested, look up the type
5011 already defined for this tag and return it. */
5013 tree ref = lookup_tag (code, name, 0);
5014 /* If this is the right type of tag, return what we found.
5015 (This reference will be shadowed by shadow_tag later if appropriate.)
5016 If this is the wrong type of tag, do not return it. If it was the
5017 wrong type in the same scope, we will have had an error
5018 message already; if in a different scope and declaring
5019 a name, pending_xref_error will give an error message; but if in a
5020 different scope and not declaring a name, this tag should
5021 shadow the previous declaration of a different type of tag, and
5022 this would not work properly if we return the reference found.
5023 (For example, with "struct foo" in an outer scope, "union foo;"
5024 must shadow that tag with a new one of union type.) */
5025 ret.kind = (ref ? ctsk_tagref : ctsk_tagfirstref);
5026 if (ref && TREE_CODE (ref) == code)
5032 /* If no such tag is yet defined, create a forward-reference node
5033 and record it as the "definition".
5034 When a real declaration of this type is found,
5035 the forward-reference will be altered into a real type. */
5037 ref = make_node (code);
5038 if (code == ENUMERAL_TYPE)
5040 /* Give the type a default layout like unsigned int
5041 to avoid crashing if it does not get defined. */
5042 TYPE_MODE (ref) = TYPE_MODE (unsigned_type_node);
5043 TYPE_ALIGN (ref) = TYPE_ALIGN (unsigned_type_node);
5044 TYPE_USER_ALIGN (ref) = 0;
5045 TYPE_UNSIGNED (ref) = 1;
5046 TYPE_PRECISION (ref) = TYPE_PRECISION (unsigned_type_node);
5047 TYPE_MIN_VALUE (ref) = TYPE_MIN_VALUE (unsigned_type_node);
5048 TYPE_MAX_VALUE (ref) = TYPE_MAX_VALUE (unsigned_type_node);
5051 pushtag (name, ref);
5057 /* Get the struct, enum or union (CODE says which) with tag NAME.
5058 Define the tag as a forward-reference if it is not defined.
5059 Return a tree for the type. */
5062 xref_tag (enum tree_code code, tree name)
5064 return parser_xref_tag (code, name).spec;
5067 /* Make sure that the tag NAME is defined *in the current scope*
5068 at least as a forward reference.
5069 CODE says which kind of tag NAME ought to be. */
5072 start_struct (enum tree_code code, tree name)
5074 /* If there is already a tag defined at this scope
5075 (as a forward reference), just return it. */
5080 ref = lookup_tag (code, name, 1);
5081 if (ref && TREE_CODE (ref) == code)
5083 if (TYPE_SIZE (ref))
5085 if (code == UNION_TYPE)
5086 error ("redefinition of %<union %E%>", name);
5088 error ("redefinition of %<struct %E%>", name);
5090 else if (C_TYPE_BEING_DEFINED (ref))
5092 if (code == UNION_TYPE)
5093 error ("nested redefinition of %<union %E%>", name);
5095 error ("nested redefinition of %<struct %E%>", name);
5100 /* Otherwise create a forward-reference just so the tag is in scope. */
5102 ref = make_node (code);
5103 pushtag (name, ref);
5106 C_TYPE_BEING_DEFINED (ref) = 1;
5107 TYPE_PACKED (ref) = flag_pack_struct;
5111 /* Process the specs, declarator and width (NULL if omitted)
5112 of a structure component, returning a FIELD_DECL node.
5113 WIDTH is non-NULL for bit-fields only, and is an INTEGER_CST node.
5115 This is done during the parsing of the struct declaration.
5116 The FIELD_DECL nodes are chained together and the lot of them
5117 are ultimately passed to `build_struct' to make the RECORD_TYPE node. */
5120 grokfield (struct c_declarator *declarator, struct c_declspecs *declspecs,
5125 if (declarator->kind == cdk_id && declarator->u.id == NULL_TREE
5126 && width == NULL_TREE)
5128 /* This is an unnamed decl.
5130 If we have something of the form "union { list } ;" then this
5131 is the anonymous union extension. Similarly for struct.
5133 If this is something of the form "struct foo;", then
5134 If MS extensions are enabled, this is handled as an
5136 Otherwise this is a forward declaration of a structure tag.
5138 If this is something of the form "foo;" and foo is a TYPE_DECL, then
5139 If MS extensions are enabled and foo names a structure, then
5140 again this is an anonymous struct.
5141 Otherwise this is an error.
5143 Oh what a horrid tangled web we weave. I wonder if MS consciously
5144 took this from Plan 9 or if it was an accident of implementation
5145 that took root before someone noticed the bug... */
5147 tree type = declspecs->type;
5148 bool type_ok = (TREE_CODE (type) == RECORD_TYPE
5149 || TREE_CODE (type) == UNION_TYPE);
5153 && (flag_ms_extensions || !declspecs->typedef_p))
5155 if (flag_ms_extensions)
5159 else if (TYPE_NAME (type) == NULL)
5166 pedwarn ("declaration does not declare anything");
5170 pedwarn ("ISO C doesn%'t support unnamed structs/unions");
5173 value = grokdeclarator (declarator, declspecs, FIELD, false,
5174 width ? &width : NULL);
5176 finish_decl (value, NULL_TREE, NULL_TREE);
5177 DECL_INITIAL (value) = width;
5182 /* Generate an error for any duplicate field names in FIELDLIST. Munge
5183 the list such that this does not present a problem later. */
5186 detect_field_duplicates (tree fieldlist)
5191 /* First, see if there are more than "a few" fields.
5192 This is trivially true if there are zero or one fields. */
5195 x = TREE_CHAIN (fieldlist);
5201 } while (timeout > 0 && x);
5203 /* If there were "few" fields, avoid the overhead of allocating
5204 a hash table. Instead just do the nested traversal thing. */
5207 for (x = TREE_CHAIN (fieldlist); x ; x = TREE_CHAIN (x))
5210 for (y = fieldlist; y != x; y = TREE_CHAIN (y))
5211 if (DECL_NAME (y) == DECL_NAME (x))
5213 error ("duplicate member %q+D", x);
5214 DECL_NAME (x) = NULL_TREE;
5220 htab_t htab = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL);
5223 for (x = fieldlist; x ; x = TREE_CHAIN (x))
5224 if ((y = DECL_NAME (x)) != 0)
5226 slot = htab_find_slot (htab, y, INSERT);
5229 error ("duplicate member %q+D", x);
5230 DECL_NAME (x) = NULL_TREE;
5239 /* Fill in the fields of a RECORD_TYPE or UNION_TYPE node, T.
5240 FIELDLIST is a chain of FIELD_DECL nodes for the fields.
5241 ATTRIBUTES are attributes to be applied to the structure. */
5244 finish_struct (tree t, tree fieldlist, tree attributes)
5247 bool toplevel = file_scope == current_scope;
5248 int saw_named_field;
5250 /* If this type was previously laid out as a forward reference,
5251 make sure we lay it out again. */
5255 decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5259 for (x = fieldlist; x; x = TREE_CHAIN (x))
5260 if (DECL_NAME (x) != 0)
5265 if (TREE_CODE (t) == UNION_TYPE)
5268 pedwarn ("union has no named members");
5270 pedwarn ("union has no members");
5275 pedwarn ("struct has no named members");
5277 pedwarn ("struct has no members");
5282 /* Install struct as DECL_CONTEXT of each field decl.
5283 Also process specified field sizes, found in the DECL_INITIAL,
5284 storing 0 there after the type has been changed to precision equal
5285 to its width, rather than the precision of the specified standard
5286 type. (Correct layout requires the original type to have been preserved
5289 saw_named_field = 0;
5290 for (x = fieldlist; x; x = TREE_CHAIN (x))
5292 DECL_CONTEXT (x) = t;
5293 DECL_PACKED (x) |= TYPE_PACKED (t);
5295 /* If any field is const, the structure type is pseudo-const. */
5296 if (TREE_READONLY (x))
5297 C_TYPE_FIELDS_READONLY (t) = 1;
5300 /* A field that is pseudo-const makes the structure likewise. */
5301 tree t1 = TREE_TYPE (x);
5302 while (TREE_CODE (t1) == ARRAY_TYPE)
5303 t1 = TREE_TYPE (t1);
5304 if ((TREE_CODE (t1) == RECORD_TYPE || TREE_CODE (t1) == UNION_TYPE)
5305 && C_TYPE_FIELDS_READONLY (t1))
5306 C_TYPE_FIELDS_READONLY (t) = 1;
5309 /* Any field that is volatile means variables of this type must be
5310 treated in some ways as volatile. */
5311 if (TREE_THIS_VOLATILE (x))
5312 C_TYPE_FIELDS_VOLATILE (t) = 1;
5314 /* Any field of nominal variable size implies structure is too. */
5315 if (C_DECL_VARIABLE_SIZE (x))
5316 C_TYPE_VARIABLE_SIZE (t) = 1;
5318 if (DECL_INITIAL (x))
5320 unsigned HOST_WIDE_INT width = tree_low_cst (DECL_INITIAL (x), 1);
5321 DECL_SIZE (x) = bitsize_int (width);
5322 DECL_BIT_FIELD (x) = 1;
5323 SET_DECL_C_BIT_FIELD (x);
5326 /* Detect flexible array member in an invalid context. */
5327 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
5328 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
5329 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
5330 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
5332 if (TREE_CODE (t) == UNION_TYPE)
5334 error ("%Jflexible array member in union", x);
5335 TREE_TYPE (x) = error_mark_node;
5337 else if (TREE_CHAIN (x) != NULL_TREE)
5339 error ("%Jflexible array member not at end of struct", x);
5340 TREE_TYPE (x) = error_mark_node;
5342 else if (!saw_named_field)
5344 error ("%Jflexible array member in otherwise empty struct", x);
5345 TREE_TYPE (x) = error_mark_node;
5349 if (pedantic && !in_system_header && TREE_CODE (t) == RECORD_TYPE
5350 && flexible_array_type_p (TREE_TYPE (x)))
5351 pedwarn ("%Jinvalid use of structure with flexible array member", x);
5354 saw_named_field = 1;
5357 detect_field_duplicates (fieldlist);
5359 /* Now we have the nearly final fieldlist. Record it,
5360 then lay out the structure or union (including the fields). */
5362 TYPE_FIELDS (t) = fieldlist;
5366 /* Give bit-fields their proper types. */
5368 tree *fieldlistp = &fieldlist;
5370 if (TREE_CODE (*fieldlistp) == FIELD_DECL && DECL_INITIAL (*fieldlistp)
5371 && TREE_TYPE (*fieldlistp) != error_mark_node)
5373 unsigned HOST_WIDE_INT width
5374 = tree_low_cst (DECL_INITIAL (*fieldlistp), 1);
5375 tree type = TREE_TYPE (*fieldlistp);
5376 if (width != TYPE_PRECISION (type))
5378 TREE_TYPE (*fieldlistp)
5379 = build_nonstandard_integer_type (width, TYPE_UNSIGNED (type));
5380 DECL_MODE (*fieldlistp) = TYPE_MODE (TREE_TYPE (*fieldlistp));
5382 DECL_INITIAL (*fieldlistp) = 0;
5385 fieldlistp = &TREE_CHAIN (*fieldlistp);
5388 /* Now we have the truly final field list.
5389 Store it in this type and in the variants. */
5391 TYPE_FIELDS (t) = fieldlist;
5393 /* If there are lots of fields, sort so we can look through them fast.
5394 We arbitrarily consider 16 or more elts to be "a lot". */
5399 for (x = fieldlist; x; x = TREE_CHAIN (x))
5401 if (len > 15 || DECL_NAME (x) == NULL)
5409 struct lang_type *space;
5410 struct sorted_fields_type *space2;
5412 len += list_length (x);
5414 /* Use the same allocation policy here that make_node uses, to
5415 ensure that this lives as long as the rest of the struct decl.
5416 All decls in an inline function need to be saved. */
5418 space = GGC_CNEW (struct lang_type);
5419 space2 = GGC_NEWVAR (struct sorted_fields_type,
5420 sizeof (struct sorted_fields_type) + len * sizeof (tree));
5424 field_array = &space2->elts[0];
5425 for (x = fieldlist; x; x = TREE_CHAIN (x))
5427 field_array[len++] = x;
5429 /* If there is anonymous struct or union, break out of the loop. */
5430 if (DECL_NAME (x) == NULL)
5433 /* Found no anonymous struct/union. Add the TYPE_LANG_SPECIFIC. */
5436 TYPE_LANG_SPECIFIC (t) = space;
5437 TYPE_LANG_SPECIFIC (t)->s->len = len;
5438 field_array = TYPE_LANG_SPECIFIC (t)->s->elts;
5439 qsort (field_array, len, sizeof (tree), field_decl_cmp);
5444 for (x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
5446 TYPE_FIELDS (x) = TYPE_FIELDS (t);
5447 TYPE_LANG_SPECIFIC (x) = TYPE_LANG_SPECIFIC (t);
5448 TYPE_ALIGN (x) = TYPE_ALIGN (t);
5449 TYPE_USER_ALIGN (x) = TYPE_USER_ALIGN (t);
5450 C_TYPE_FIELDS_READONLY (x) = C_TYPE_FIELDS_READONLY (t);
5451 C_TYPE_FIELDS_VOLATILE (x) = C_TYPE_FIELDS_VOLATILE (t);
5452 C_TYPE_VARIABLE_SIZE (x) = C_TYPE_VARIABLE_SIZE (t);
5455 /* If this was supposed to be a transparent union, but we can't
5456 make it one, warn and turn off the flag. */
5457 if (TREE_CODE (t) == UNION_TYPE
5458 && TYPE_TRANSPARENT_UNION (t)
5459 && (!TYPE_FIELDS (t) || TYPE_MODE (t) != DECL_MODE (TYPE_FIELDS (t))))
5461 TYPE_TRANSPARENT_UNION (t) = 0;
5462 warning (0, "union cannot be made transparent");
5465 /* If this structure or union completes the type of any previous
5466 variable declaration, lay it out and output its rtl. */
5467 for (x = C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t));
5471 tree decl = TREE_VALUE (x);
5472 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
5473 layout_array_type (TREE_TYPE (decl));
5474 if (TREE_CODE (decl) != TYPE_DECL)
5476 layout_decl (decl, 0);
5477 if (c_dialect_objc ())
5478 objc_check_decl (decl);
5479 rest_of_decl_compilation (decl, toplevel, 0);
5484 C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t)) = 0;
5486 /* Finish debugging output for this type. */
5487 rest_of_type_compilation (t, toplevel);
5489 /* If we're inside a function proper, i.e. not file-scope and not still
5490 parsing parameters, then arrange for the size of a variable sized type
5492 if (cur_stmt_list && variably_modified_type_p (t, NULL))
5493 add_stmt (build_stmt (DECL_EXPR, build_decl (TYPE_DECL, NULL, t)));
5498 /* Lay out the type T, and its element type, and so on. */
5501 layout_array_type (tree t)
5503 if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
5504 layout_array_type (TREE_TYPE (t));
5508 /* Begin compiling the definition of an enumeration type.
5509 NAME is its name (or null if anonymous).
5510 Returns the type object, as yet incomplete.
5511 Also records info about it so that build_enumerator
5512 may be used to declare the individual values as they are read. */
5515 start_enum (tree name)
5519 /* If this is the real definition for a previous forward reference,
5520 fill in the contents in the same object that used to be the
5521 forward reference. */
5524 enumtype = lookup_tag (ENUMERAL_TYPE, name, 1);
5526 if (enumtype == 0 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
5528 enumtype = make_node (ENUMERAL_TYPE);
5529 pushtag (name, enumtype);
5532 if (C_TYPE_BEING_DEFINED (enumtype))
5533 error ("nested redefinition of %<enum %E%>", name);
5535 C_TYPE_BEING_DEFINED (enumtype) = 1;
5537 if (TYPE_VALUES (enumtype) != 0)
5539 /* This enum is a named one that has been declared already. */
5540 error ("redeclaration of %<enum %E%>", name);
5542 /* Completely replace its old definition.
5543 The old enumerators remain defined, however. */
5544 TYPE_VALUES (enumtype) = 0;
5547 enum_next_value = integer_zero_node;
5550 if (flag_short_enums)
5551 TYPE_PACKED (enumtype) = 1;
5556 /* After processing and defining all the values of an enumeration type,
5557 install their decls in the enumeration type and finish it off.
5558 ENUMTYPE is the type object, VALUES a list of decl-value pairs,
5559 and ATTRIBUTES are the specified attributes.
5560 Returns ENUMTYPE. */
5563 finish_enum (tree enumtype, tree values, tree attributes)
5566 tree minnode = 0, maxnode = 0;
5567 int precision, unsign;
5568 bool toplevel = (file_scope == current_scope);
5569 struct lang_type *lt;
5571 decl_attributes (&enumtype, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5573 /* Calculate the maximum value of any enumerator in this type. */
5575 if (values == error_mark_node)
5576 minnode = maxnode = integer_zero_node;
5579 minnode = maxnode = TREE_VALUE (values);
5580 for (pair = TREE_CHAIN (values); pair; pair = TREE_CHAIN (pair))
5582 tree value = TREE_VALUE (pair);
5583 if (tree_int_cst_lt (maxnode, value))
5585 if (tree_int_cst_lt (value, minnode))
5590 /* Construct the final type of this enumeration. It is the same
5591 as one of the integral types - the narrowest one that fits, except
5592 that normally we only go as narrow as int - and signed iff any of
5593 the values are negative. */
5594 unsign = (tree_int_cst_sgn (minnode) >= 0);
5595 precision = MAX (min_precision (minnode, unsign),
5596 min_precision (maxnode, unsign));
5598 if (TYPE_PACKED (enumtype) || precision > TYPE_PRECISION (integer_type_node))
5600 tem = c_common_type_for_size (precision, unsign);
5603 warning (0, "enumeration values exceed range of largest integer");
5604 tem = long_long_integer_type_node;
5608 tem = unsign ? unsigned_type_node : integer_type_node;
5610 TYPE_MIN_VALUE (enumtype) = TYPE_MIN_VALUE (tem);
5611 TYPE_MAX_VALUE (enumtype) = TYPE_MAX_VALUE (tem);
5612 TYPE_UNSIGNED (enumtype) = TYPE_UNSIGNED (tem);
5613 TYPE_SIZE (enumtype) = 0;
5615 /* If the precision of the type was specific with an attribute and it
5616 was too small, give an error. Otherwise, use it. */
5617 if (TYPE_PRECISION (enumtype))
5619 if (precision > TYPE_PRECISION (enumtype))
5620 error ("specified mode too small for enumeral values");
5623 TYPE_PRECISION (enumtype) = TYPE_PRECISION (tem);
5625 layout_type (enumtype);
5627 if (values != error_mark_node)
5629 /* Change the type of the enumerators to be the enum type. We
5630 need to do this irrespective of the size of the enum, for
5631 proper type checking. Replace the DECL_INITIALs of the
5632 enumerators, and the value slots of the list, with copies
5633 that have the enum type; they cannot be modified in place
5634 because they may be shared (e.g. integer_zero_node) Finally,
5635 change the purpose slots to point to the names of the decls. */
5636 for (pair = values; pair; pair = TREE_CHAIN (pair))
5638 tree enu = TREE_PURPOSE (pair);
5639 tree ini = DECL_INITIAL (enu);
5641 TREE_TYPE (enu) = enumtype;
5643 /* The ISO C Standard mandates enumerators to have type int,
5644 even though the underlying type of an enum type is
5645 unspecified. Here we convert any enumerators that fit in
5646 an int to type int, to avoid promotions to unsigned types
5647 when comparing integers with enumerators that fit in the
5648 int range. When -pedantic is given, build_enumerator()
5649 would have already taken care of those that don't fit. */
5650 if (int_fits_type_p (ini, integer_type_node))
5651 tem = integer_type_node;
5654 ini = convert (tem, ini);
5656 DECL_INITIAL (enu) = ini;
5657 TREE_PURPOSE (pair) = DECL_NAME (enu);
5658 TREE_VALUE (pair) = ini;
5661 TYPE_VALUES (enumtype) = values;
5664 /* Record the min/max values so that we can warn about bit-field
5665 enumerations that are too small for the values. */
5666 lt = GGC_CNEW (struct lang_type);
5667 lt->enum_min = minnode;
5668 lt->enum_max = maxnode;
5669 TYPE_LANG_SPECIFIC (enumtype) = lt;
5671 /* Fix up all variant types of this enum type. */
5672 for (tem = TYPE_MAIN_VARIANT (enumtype); tem; tem = TYPE_NEXT_VARIANT (tem))
5674 if (tem == enumtype)
5676 TYPE_VALUES (tem) = TYPE_VALUES (enumtype);
5677 TYPE_MIN_VALUE (tem) = TYPE_MIN_VALUE (enumtype);
5678 TYPE_MAX_VALUE (tem) = TYPE_MAX_VALUE (enumtype);
5679 TYPE_SIZE (tem) = TYPE_SIZE (enumtype);
5680 TYPE_SIZE_UNIT (tem) = TYPE_SIZE_UNIT (enumtype);
5681 TYPE_MODE (tem) = TYPE_MODE (enumtype);
5682 TYPE_PRECISION (tem) = TYPE_PRECISION (enumtype);
5683 TYPE_ALIGN (tem) = TYPE_ALIGN (enumtype);
5684 TYPE_USER_ALIGN (tem) = TYPE_USER_ALIGN (enumtype);
5685 TYPE_UNSIGNED (tem) = TYPE_UNSIGNED (enumtype);
5686 TYPE_LANG_SPECIFIC (tem) = TYPE_LANG_SPECIFIC (enumtype);
5689 /* Finish debugging output for this type. */
5690 rest_of_type_compilation (enumtype, toplevel);
5695 /* Build and install a CONST_DECL for one value of the
5696 current enumeration type (one that was begun with start_enum).
5697 Return a tree-list containing the CONST_DECL and its value.
5698 Assignment of sequential values by default is handled here. */
5701 build_enumerator (tree name, tree value)
5705 /* Validate and default VALUE. */
5709 /* Don't issue more errors for error_mark_node (i.e. an
5710 undeclared identifier) - just ignore the value expression. */
5711 if (value == error_mark_node)
5713 else if (!INTEGRAL_TYPE_P (TREE_TYPE (value))
5714 || TREE_CODE (value) != INTEGER_CST)
5716 error ("enumerator value for %qE is not an integer constant", name);
5721 value = default_conversion (value);
5722 constant_expression_warning (value);
5726 /* Default based on previous value. */
5727 /* It should no longer be possible to have NON_LVALUE_EXPR
5731 value = enum_next_value;
5733 error ("overflow in enumeration values");
5736 if (pedantic && !int_fits_type_p (value, integer_type_node))
5738 pedwarn ("ISO C restricts enumerator values to range of %<int%>");
5739 /* XXX This causes -pedantic to change the meaning of the program.
5740 Remove? -zw 2004-03-15 */
5741 value = convert (integer_type_node, value);
5744 /* Set basis for default for next value. */
5745 enum_next_value = build_binary_op (PLUS_EXPR, value, integer_one_node, 0);
5746 enum_overflow = tree_int_cst_lt (enum_next_value, value);
5748 /* Now create a declaration for the enum value name. */
5750 type = TREE_TYPE (value);
5751 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
5752 TYPE_PRECISION (integer_type_node)),
5753 (TYPE_PRECISION (type)
5754 >= TYPE_PRECISION (integer_type_node)
5755 && TYPE_UNSIGNED (type)));
5757 decl = build_decl (CONST_DECL, name, type);
5758 DECL_INITIAL (decl) = convert (type, value);
5761 return tree_cons (decl, value, NULL_TREE);
5765 /* Create the FUNCTION_DECL for a function definition.
5766 DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of
5767 the declaration; they describe the function's name and the type it returns,
5768 but twisted together in a fashion that parallels the syntax of C.
5770 This function creates a binding context for the function body
5771 as well as setting up the FUNCTION_DECL in current_function_decl.
5773 Returns 1 on success. If the DECLARATOR is not suitable for a function
5774 (it defines a datum instead), we return 0, which tells
5775 yyparse to report a parse error. */
5778 start_function (struct c_declspecs *declspecs, struct c_declarator *declarator,
5781 tree decl1, old_decl;
5782 tree restype, resdecl;
5783 struct c_label_context_se *nstack_se;
5784 struct c_label_context_vm *nstack_vm;
5786 current_function_returns_value = 0; /* Assume, until we see it does. */
5787 current_function_returns_null = 0;
5788 current_function_returns_abnormally = 0;
5789 warn_about_return_type = 0;
5790 current_extern_inline = 0;
5791 c_switch_stack = NULL;
5793 nstack_se = XOBNEW (&parser_obstack, struct c_label_context_se);
5794 nstack_se->labels_def = NULL;
5795 nstack_se->labels_used = NULL;
5796 nstack_se->next = label_context_stack_se;
5797 label_context_stack_se = nstack_se;
5799 nstack_vm = XOBNEW (&parser_obstack, struct c_label_context_vm);
5800 nstack_vm->labels_def = NULL;
5801 nstack_vm->labels_used = NULL;
5802 nstack_vm->scope = 0;
5803 nstack_vm->next = label_context_stack_vm;
5804 label_context_stack_vm = nstack_vm;
5806 /* Indicate no valid break/continue context by setting these variables
5807 to some non-null, non-label value. We'll notice and emit the proper
5808 error message in c_finish_bc_stmt. */
5809 c_break_label = c_cont_label = size_zero_node;
5811 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, true, NULL);
5813 /* If the declarator is not suitable for a function definition,
5814 cause a syntax error. */
5817 label_context_stack_se = label_context_stack_se->next;
5818 label_context_stack_vm = label_context_stack_vm->next;
5822 decl_attributes (&decl1, attributes, 0);
5824 if (DECL_DECLARED_INLINE_P (decl1)
5825 && DECL_UNINLINABLE (decl1)
5826 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl1)))
5827 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
5830 announce_function (decl1);
5832 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl1))))
5834 error ("return type is an incomplete type");
5835 /* Make it return void instead. */
5837 = build_function_type (void_type_node,
5838 TYPE_ARG_TYPES (TREE_TYPE (decl1)));
5841 if (warn_about_return_type)
5842 pedwarn_c99 ("return type defaults to %<int%>");
5844 /* Make the init_value nonzero so pushdecl knows this is not tentative.
5845 error_mark_node is replaced below (in pop_scope) with the BLOCK. */
5846 DECL_INITIAL (decl1) = error_mark_node;
5848 /* If this definition isn't a prototype and we had a prototype declaration
5849 before, copy the arg type info from that prototype. */
5850 old_decl = lookup_name_in_scope (DECL_NAME (decl1), current_scope);
5851 current_function_prototype_locus = UNKNOWN_LOCATION;
5852 current_function_prototype_built_in = false;
5853 current_function_prototype_arg_types = NULL_TREE;
5854 if (TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0)
5856 if (old_decl != 0 && TREE_CODE (TREE_TYPE (old_decl)) == FUNCTION_TYPE
5857 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
5858 TREE_TYPE (TREE_TYPE (old_decl))))
5860 TREE_TYPE (decl1) = composite_type (TREE_TYPE (old_decl),
5862 current_function_prototype_locus = DECL_SOURCE_LOCATION (old_decl);
5863 current_function_prototype_built_in
5864 = C_DECL_BUILTIN_PROTOTYPE (old_decl);
5865 current_function_prototype_arg_types
5866 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
5868 if (TREE_PUBLIC (decl1))
5870 /* If there is an external prototype declaration of this
5871 function, record its location but do not copy information
5872 to this decl. This may be an invisible declaration
5873 (built-in or in a scope which has finished) or simply
5874 have more refined argument types than any declaration
5876 struct c_binding *b;
5877 for (b = I_SYMBOL_BINDING (DECL_NAME (decl1)); b; b = b->shadowed)
5878 if (B_IN_SCOPE (b, external_scope))
5882 tree ext_decl, ext_type;
5884 ext_type = b->type ? b->type : TREE_TYPE (ext_decl);
5885 if (TREE_CODE (ext_type) == FUNCTION_TYPE
5886 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
5887 TREE_TYPE (ext_type)))
5889 current_function_prototype_locus
5890 = DECL_SOURCE_LOCATION (ext_decl);
5891 current_function_prototype_built_in
5892 = C_DECL_BUILTIN_PROTOTYPE (ext_decl);
5893 current_function_prototype_arg_types
5894 = TYPE_ARG_TYPES (ext_type);
5900 /* Optionally warn of old-fashioned def with no previous prototype. */
5901 if (warn_strict_prototypes
5902 && old_decl != error_mark_node
5903 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0
5904 && C_DECL_ISNT_PROTOTYPE (old_decl))
5905 warning (OPT_Wstrict_prototypes,
5906 "function declaration isn%'t a prototype");
5907 /* Optionally warn of any global def with no previous prototype. */
5908 else if (warn_missing_prototypes
5909 && old_decl != error_mark_node
5910 && TREE_PUBLIC (decl1)
5911 && !MAIN_NAME_P (DECL_NAME (decl1))
5912 && C_DECL_ISNT_PROTOTYPE (old_decl))
5913 warning (OPT_Wmissing_prototypes, "no previous prototype for %q+D", decl1);
5914 /* Optionally warn of any def with no previous prototype
5915 if the function has already been used. */
5916 else if (warn_missing_prototypes
5918 && old_decl != error_mark_node
5919 && TREE_USED (old_decl)
5920 && TYPE_ARG_TYPES (TREE_TYPE (old_decl)) == 0)
5921 warning (OPT_Wmissing_prototypes,
5922 "%q+D was used with no prototype before its definition", decl1);
5923 /* Optionally warn of any global def with no previous declaration. */
5924 else if (warn_missing_declarations
5925 && TREE_PUBLIC (decl1)
5927 && !MAIN_NAME_P (DECL_NAME (decl1)))
5928 warning (OPT_Wmissing_declarations, "no previous declaration for %q+D",
5930 /* Optionally warn of any def with no previous declaration
5931 if the function has already been used. */
5932 else if (warn_missing_declarations
5934 && old_decl != error_mark_node
5935 && TREE_USED (old_decl)
5936 && C_DECL_IMPLICIT (old_decl))
5937 warning (OPT_Wmissing_declarations,
5938 "%q+D was used with no declaration before its definition", decl1);
5940 /* This is a definition, not a reference.
5941 So normally clear DECL_EXTERNAL.
5942 However, `extern inline' acts like a declaration
5943 except for defining how to inline. So set DECL_EXTERNAL in that case. */
5944 DECL_EXTERNAL (decl1) = current_extern_inline;
5946 /* This function exists in static storage.
5947 (This does not mean `static' in the C sense!) */
5948 TREE_STATIC (decl1) = 1;
5950 /* A nested function is not global. */
5951 if (current_function_decl != 0)
5952 TREE_PUBLIC (decl1) = 0;
5954 /* This is the earliest point at which we might know the assembler
5955 name of the function. Thus, if it's set before this, die horribly. */
5956 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl1));
5958 /* If #pragma weak was used, mark the decl weak now. */
5959 if (current_scope == file_scope)
5960 maybe_apply_pragma_weak (decl1);
5962 /* Warn for unlikely, improbable, or stupid declarations of `main'. */
5963 if (warn_main > 0 && MAIN_NAME_P (DECL_NAME (decl1)))
5968 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
5969 != integer_type_node)
5970 pedwarn ("return type of %q+D is not %<int%>", decl1);
5972 for (args = TYPE_ARG_TYPES (TREE_TYPE (decl1)); args;
5973 args = TREE_CHAIN (args))
5975 tree type = args ? TREE_VALUE (args) : 0;
5977 if (type == void_type_node)
5984 if (TYPE_MAIN_VARIANT (type) != integer_type_node)
5985 pedwarn ("first argument of %q+D should be %<int%>", decl1);
5989 if (TREE_CODE (type) != POINTER_TYPE
5990 || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
5991 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
5993 pedwarn ("second argument of %q+D should be %<char **%>",
5998 if (TREE_CODE (type) != POINTER_TYPE
5999 || TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE
6000 || (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (type)))
6002 pedwarn ("third argument of %q+D should probably be "
6003 "%<char **%>", decl1);
6008 /* It is intentional that this message does not mention the third
6009 argument because it's only mentioned in an appendix of the
6011 if (argct > 0 && (argct < 2 || argct > 3))
6012 pedwarn ("%q+D takes only zero or two arguments", decl1);
6014 if (!TREE_PUBLIC (decl1))
6015 pedwarn ("%q+D is normally a non-static function", decl1);
6018 /* Record the decl so that the function name is defined.
6019 If we already have a decl for this name, and it is a FUNCTION_DECL,
6020 use the old decl. */
6022 current_function_decl = pushdecl (decl1);
6025 declare_parm_level ();
6027 restype = TREE_TYPE (TREE_TYPE (current_function_decl));
6028 /* Promote the value to int before returning it. */
6029 if (c_promoting_integer_type_p (restype))
6031 /* It retains unsignedness if not really getting wider. */
6032 if (TYPE_UNSIGNED (restype)
6033 && (TYPE_PRECISION (restype)
6034 == TYPE_PRECISION (integer_type_node)))
6035 restype = unsigned_type_node;
6037 restype = integer_type_node;
6040 resdecl = build_decl (RESULT_DECL, NULL_TREE, restype);
6041 DECL_ARTIFICIAL (resdecl) = 1;
6042 DECL_IGNORED_P (resdecl) = 1;
6043 DECL_RESULT (current_function_decl) = resdecl;
6045 start_fname_decls ();
6050 /* Subroutine of store_parm_decls which handles new-style function
6051 definitions (prototype format). The parms already have decls, so we
6052 need only record them as in effect and complain if any redundant
6053 old-style parm decls were written. */
6055 store_parm_decls_newstyle (tree fndecl, const struct c_arg_info *arg_info)
6059 if (current_scope->bindings)
6061 error ("%Jold-style parameter declarations in prototyped "
6062 "function definition", fndecl);
6064 /* Get rid of the old-style declarations. */
6068 /* Don't issue this warning for nested functions, and don't issue this
6069 warning if we got here because ARG_INFO_TYPES was error_mark_node
6070 (this happens when a function definition has just an ellipsis in
6071 its parameter list). */
6072 else if (!in_system_header && !current_function_scope
6073 && arg_info->types != error_mark_node)
6074 warning (OPT_Wtraditional,
6075 "%Jtraditional C rejects ISO C style function definitions",
6078 /* Now make all the parameter declarations visible in the function body.
6079 We can bypass most of the grunt work of pushdecl. */
6080 for (decl = arg_info->parms; decl; decl = TREE_CHAIN (decl))
6082 DECL_CONTEXT (decl) = current_function_decl;
6083 if (DECL_NAME (decl))
6084 bind (DECL_NAME (decl), decl, current_scope,
6085 /*invisible=*/false, /*nested=*/false);
6087 error ("%Jparameter name omitted", decl);
6090 /* Record the parameter list in the function declaration. */
6091 DECL_ARGUMENTS (fndecl) = arg_info->parms;
6093 /* Now make all the ancillary declarations visible, likewise. */
6094 for (decl = arg_info->others; decl; decl = TREE_CHAIN (decl))
6096 DECL_CONTEXT (decl) = current_function_decl;
6097 if (DECL_NAME (decl))
6098 bind (DECL_NAME (decl), decl, current_scope,
6099 /*invisible=*/false, /*nested=*/false);
6102 /* And all the tag declarations. */
6103 for (decl = arg_info->tags; decl; decl = TREE_CHAIN (decl))
6104 if (TREE_PURPOSE (decl))
6105 bind (TREE_PURPOSE (decl), TREE_VALUE (decl), current_scope,
6106 /*invisible=*/false, /*nested=*/false);
6109 /* Subroutine of store_parm_decls which handles old-style function
6110 definitions (separate parameter list and declarations). */
6113 store_parm_decls_oldstyle (tree fndecl, const struct c_arg_info *arg_info)
6115 struct c_binding *b;
6116 tree parm, decl, last;
6117 tree parmids = arg_info->parms;
6118 struct pointer_set_t *seen_args = pointer_set_create ();
6120 if (!in_system_header)
6121 warning (OPT_Wold_style_definition, "%Jold-style function definition",
6124 /* Match each formal parameter name with its declaration. Save each
6125 decl in the appropriate TREE_PURPOSE slot of the parmids chain. */
6126 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6128 if (TREE_VALUE (parm) == 0)
6130 error ("%Jparameter name missing from parameter list", fndecl);
6131 TREE_PURPOSE (parm) = 0;
6135 b = I_SYMBOL_BINDING (TREE_VALUE (parm));
6136 if (b && B_IN_CURRENT_SCOPE (b))
6139 /* If we got something other than a PARM_DECL it is an error. */
6140 if (TREE_CODE (decl) != PARM_DECL)
6141 error ("%q+D declared as a non-parameter", decl);
6142 /* If the declaration is already marked, we have a duplicate
6143 name. Complain and ignore the duplicate. */
6144 else if (pointer_set_contains (seen_args, decl))
6146 error ("multiple parameters named %q+D", decl);
6147 TREE_PURPOSE (parm) = 0;
6150 /* If the declaration says "void", complain and turn it into
6152 else if (VOID_TYPE_P (TREE_TYPE (decl)))
6154 error ("parameter %q+D declared with void type", decl);
6155 TREE_TYPE (decl) = integer_type_node;
6156 DECL_ARG_TYPE (decl) = integer_type_node;
6157 layout_decl (decl, 0);
6160 /* If no declaration found, default to int. */
6163 decl = build_decl (PARM_DECL, TREE_VALUE (parm), integer_type_node);
6164 DECL_ARG_TYPE (decl) = TREE_TYPE (decl);
6165 DECL_SOURCE_LOCATION (decl) = DECL_SOURCE_LOCATION (fndecl);
6169 pedwarn ("type of %q+D defaults to %<int%>", decl);
6170 else if (extra_warnings)
6171 warning (OPT_Wextra, "type of %q+D defaults to %<int%>", decl);
6174 TREE_PURPOSE (parm) = decl;
6175 pointer_set_insert (seen_args, decl);
6178 /* Now examine the parms chain for incomplete declarations
6179 and declarations with no corresponding names. */
6181 for (b = current_scope->bindings; b; b = b->prev)
6184 if (TREE_CODE (parm) != PARM_DECL)
6187 if (TREE_TYPE (parm) != error_mark_node
6188 && !COMPLETE_TYPE_P (TREE_TYPE (parm)))
6190 error ("parameter %q+D has incomplete type", parm);
6191 TREE_TYPE (parm) = error_mark_node;
6194 if (!pointer_set_contains (seen_args, parm))
6196 error ("declaration for parameter %q+D but no such parameter", parm);
6198 /* Pretend the parameter was not missing.
6199 This gets us to a standard state and minimizes
6200 further error messages. */
6201 parmids = chainon (parmids, tree_cons (parm, 0, 0));
6205 /* Chain the declarations together in the order of the list of
6206 names. Store that chain in the function decl, replacing the
6207 list of names. Update the current scope to match. */
6208 DECL_ARGUMENTS (fndecl) = 0;
6210 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6211 if (TREE_PURPOSE (parm))
6213 if (parm && TREE_PURPOSE (parm))
6215 last = TREE_PURPOSE (parm);
6216 DECL_ARGUMENTS (fndecl) = last;
6218 for (parm = TREE_CHAIN (parm); parm; parm = TREE_CHAIN (parm))
6219 if (TREE_PURPOSE (parm))
6221 TREE_CHAIN (last) = TREE_PURPOSE (parm);
6222 last = TREE_PURPOSE (parm);
6224 TREE_CHAIN (last) = 0;
6227 pointer_set_destroy (seen_args);
6229 /* If there was a previous prototype,
6230 set the DECL_ARG_TYPE of each argument according to
6231 the type previously specified, and report any mismatches. */
6233 if (current_function_prototype_arg_types)
6236 for (parm = DECL_ARGUMENTS (fndecl),
6237 type = current_function_prototype_arg_types;
6238 parm || (type && (TYPE_MAIN_VARIANT (TREE_VALUE (type))
6239 != void_type_node));
6240 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
6242 if (parm == 0 || type == 0
6243 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
6245 if (current_function_prototype_built_in)
6246 warning (0, "number of arguments doesn%'t match "
6247 "built-in prototype");
6250 error ("number of arguments doesn%'t match prototype");
6251 error ("%Hprototype declaration",
6252 ¤t_function_prototype_locus);
6256 /* Type for passing arg must be consistent with that
6257 declared for the arg. ISO C says we take the unqualified
6258 type for parameters declared with qualified type. */
6259 if (!comptypes (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (parm)),
6260 TYPE_MAIN_VARIANT (TREE_VALUE (type))))
6262 if (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
6263 == TYPE_MAIN_VARIANT (TREE_VALUE (type)))
6265 /* Adjust argument to match prototype. E.g. a previous
6266 `int foo(float);' prototype causes
6267 `int foo(x) float x; {...}' to be treated like
6268 `int foo(float x) {...}'. This is particularly
6269 useful for argument types like uid_t. */
6270 DECL_ARG_TYPE (parm) = TREE_TYPE (parm);
6272 if (targetm.calls.promote_prototypes (TREE_TYPE (current_function_decl))
6273 && INTEGRAL_TYPE_P (TREE_TYPE (parm))
6274 && TYPE_PRECISION (TREE_TYPE (parm))
6275 < TYPE_PRECISION (integer_type_node))
6276 DECL_ARG_TYPE (parm) = integer_type_node;
6280 /* ??? Is it possible to get here with a
6281 built-in prototype or will it always have
6282 been diagnosed as conflicting with an
6283 old-style definition and discarded? */
6284 if (current_function_prototype_built_in)
6285 warning (0, "promoted argument %qD "
6286 "doesn%'t match built-in prototype", parm);
6289 pedwarn ("promoted argument %qD "
6290 "doesn%'t match prototype", parm);
6291 pedwarn ("%Hprototype declaration",
6292 ¤t_function_prototype_locus);
6298 if (current_function_prototype_built_in)
6299 warning (0, "argument %qD doesn%'t match "
6300 "built-in prototype", parm);
6303 error ("argument %qD doesn%'t match prototype", parm);
6304 error ("%Hprototype declaration",
6305 ¤t_function_prototype_locus);
6310 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = 0;
6313 /* Otherwise, create a prototype that would match. */
6317 tree actual = 0, last = 0, type;
6319 for (parm = DECL_ARGUMENTS (fndecl); parm; parm = TREE_CHAIN (parm))
6321 type = tree_cons (NULL_TREE, DECL_ARG_TYPE (parm), NULL_TREE);
6323 TREE_CHAIN (last) = type;
6328 type = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
6330 TREE_CHAIN (last) = type;
6334 /* We are going to assign a new value for the TYPE_ACTUAL_ARG_TYPES
6335 of the type of this function, but we need to avoid having this
6336 affect the types of other similarly-typed functions, so we must
6337 first force the generation of an identical (but separate) type
6338 node for the relevant function type. The new node we create
6339 will be a variant of the main variant of the original function
6342 TREE_TYPE (fndecl) = build_variant_type_copy (TREE_TYPE (fndecl));
6344 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = actual;
6348 /* Store parameter declarations passed in ARG_INFO into the current
6349 function declaration. */
6352 store_parm_decls_from (struct c_arg_info *arg_info)
6354 current_function_arg_info = arg_info;
6355 store_parm_decls ();
6358 /* Store the parameter declarations into the current function declaration.
6359 This is called after parsing the parameter declarations, before
6360 digesting the body of the function.
6362 For an old-style definition, construct a prototype out of the old-style
6363 parameter declarations and inject it into the function's type. */
6366 store_parm_decls (void)
6368 tree fndecl = current_function_decl;
6371 /* The argument information block for FNDECL. */
6372 struct c_arg_info *arg_info = current_function_arg_info;
6373 current_function_arg_info = 0;
6375 /* True if this definition is written with a prototype. Note:
6376 despite C99 6.7.5.3p14, we can *not* treat an empty argument
6377 list in a function definition as equivalent to (void) -- an
6378 empty argument list specifies the function has no parameters,
6379 but only (void) sets up a prototype for future calls. */
6380 proto = arg_info->types != 0;
6383 store_parm_decls_newstyle (fndecl, arg_info);
6385 store_parm_decls_oldstyle (fndecl, arg_info);
6387 /* The next call to push_scope will be a function body. */
6389 next_is_function_body = true;
6391 /* Write a record describing this function definition to the prototypes
6392 file (if requested). */
6394 gen_aux_info_record (fndecl, 1, 0, proto);
6396 /* Initialize the RTL code for the function. */
6397 allocate_struct_function (fndecl);
6399 /* Begin the statement tree for this function. */
6400 DECL_SAVED_TREE (fndecl) = push_stmt_list ();
6402 /* ??? Insert the contents of the pending sizes list into the function
6403 to be evaluated. The only reason left to have this is
6404 void foo(int n, int array[n++])
6405 because we throw away the array type in favor of a pointer type, and
6406 thus won't naturally see the SAVE_EXPR containing the increment. All
6407 other pending sizes would be handled by gimplify_parameters. */
6410 for (t = nreverse (get_pending_sizes ()); t ; t = TREE_CHAIN (t))
6411 add_stmt (TREE_VALUE (t));
6414 /* Even though we're inside a function body, we still don't want to
6415 call expand_expr to calculate the size of a variable-sized array.
6416 We haven't necessarily assigned RTL to all variables yet, so it's
6417 not safe to try to expand expressions involving them. */
6418 cfun->x_dont_save_pending_sizes_p = 1;
6421 /* Handle attribute((warn_unused_result)) on FNDECL and all its nested
6425 c_warn_unused_result_recursively (tree fndecl)
6427 struct cgraph_node *cgn;
6429 /* Handle attribute((warn_unused_result)). Relies on gimple input. */
6430 c_warn_unused_result (&DECL_SAVED_TREE (fndecl));
6432 /* Finalize all nested functions now. */
6433 cgn = cgraph_node (fndecl);
6434 for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested)
6435 c_warn_unused_result_recursively (cgn->decl);
6438 /* Finish up a function declaration and compile that function
6439 all the way to assembler language output. The free the storage
6440 for the function definition.
6442 This is called after parsing the body of the function definition. */
6445 finish_function (void)
6447 tree fndecl = current_function_decl;
6449 label_context_stack_se = label_context_stack_se->next;
6450 label_context_stack_vm = label_context_stack_vm->next;
6452 if (TREE_CODE (fndecl) == FUNCTION_DECL
6453 && targetm.calls.promote_prototypes (TREE_TYPE (fndecl)))
6455 tree args = DECL_ARGUMENTS (fndecl);
6456 for (; args; args = TREE_CHAIN (args))
6458 tree type = TREE_TYPE (args);
6459 if (INTEGRAL_TYPE_P (type)
6460 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
6461 DECL_ARG_TYPE (args) = integer_type_node;
6465 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node)
6466 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
6468 /* Must mark the RESULT_DECL as being in this function. */
6470 if (DECL_RESULT (fndecl) && DECL_RESULT (fndecl) != error_mark_node)
6471 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
6473 if (MAIN_NAME_P (DECL_NAME (fndecl)) && flag_hosted)
6475 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (fndecl)))
6476 != integer_type_node)
6478 /* If warn_main is 1 (-Wmain) or 2 (-Wall), we have already warned.
6479 If warn_main is -1 (-Wno-main) we don't want to be warned. */
6481 pedwarn ("return type of %q+D is not %<int%>", fndecl);
6487 tree stmt = c_finish_return (integer_zero_node);
6488 #ifdef USE_MAPPED_LOCATION
6489 /* Hack. We don't want the middle-end to warn that this return
6490 is unreachable, so we mark its location as special. Using
6491 UNKNOWN_LOCATION has the problem that it gets clobbered in
6492 annotate_one_with_locus. A cleaner solution might be to
6493 ensure ! should_carry_locus_p (stmt), but that needs a flag.
6495 SET_EXPR_LOCATION (stmt, BUILTINS_LOCATION);
6497 /* Hack. We don't want the middle-end to warn that this
6498 return is unreachable, so put the statement on the
6500 annotate_with_file_line (stmt, input_filename, 0);
6506 /* Tie off the statement tree for this function. */
6507 DECL_SAVED_TREE (fndecl) = pop_stmt_list (DECL_SAVED_TREE (fndecl));
6509 finish_fname_decls ();
6511 /* Complain if there's just no return statement. */
6512 if (warn_return_type
6513 && TREE_CODE (TREE_TYPE (TREE_TYPE (fndecl))) != VOID_TYPE
6514 && !current_function_returns_value && !current_function_returns_null
6515 /* Don't complain if we are no-return. */
6516 && !current_function_returns_abnormally
6517 /* Don't warn for main(). */
6518 && !MAIN_NAME_P (DECL_NAME (fndecl))
6519 /* Or if they didn't actually specify a return type. */
6520 && !C_FUNCTION_IMPLICIT_INT (fndecl)
6521 /* Normally, with -Wreturn-type, flow will complain. Unless we're an
6522 inline function, as we might never be compiled separately. */
6523 && DECL_INLINE (fndecl))
6525 warning (OPT_Wreturn_type,
6526 "no return statement in function returning non-void");
6527 TREE_NO_WARNING (fndecl) = 1;
6530 /* With just -Wextra, complain only if function returns both with
6531 and without a value. */
6533 && current_function_returns_value
6534 && current_function_returns_null)
6535 warning (OPT_Wextra, "this function may return with or without a value");
6537 /* Store the end of the function, so that we get good line number
6538 info for the epilogue. */
6539 cfun->function_end_locus = input_location;
6541 /* If we don't have ctors/dtors sections, and this is a static
6542 constructor or destructor, it must be recorded now. */
6543 if (DECL_STATIC_CONSTRUCTOR (fndecl)
6544 && !targetm.have_ctors_dtors)
6545 static_ctors = tree_cons (NULL_TREE, fndecl, static_ctors);
6546 if (DECL_STATIC_DESTRUCTOR (fndecl)
6547 && !targetm.have_ctors_dtors)
6548 static_dtors = tree_cons (NULL_TREE, fndecl, static_dtors);
6550 /* Finalize the ELF visibility for the function. */
6551 c_determine_visibility (fndecl);
6553 /* Genericize before inlining. Delay genericizing nested functions
6554 until their parent function is genericized. Since finalizing
6555 requires GENERIC, delay that as well. */
6557 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node
6558 && !undef_nested_function)
6560 if (!decl_function_context (fndecl))
6562 c_genericize (fndecl);
6563 c_warn_unused_result_recursively (fndecl);
6565 /* ??? Objc emits functions after finalizing the compilation unit.
6566 This should be cleaned up later and this conditional removed. */
6567 if (cgraph_global_info_ready)
6569 c_expand_body (fndecl);
6573 cgraph_finalize_function (fndecl, false);
6577 /* Register this function with cgraph just far enough to get it
6578 added to our parent's nested function list. Handy, since the
6579 C front end doesn't have such a list. */
6580 (void) cgraph_node (fndecl);
6584 if (!decl_function_context (fndecl))
6585 undef_nested_function = false;
6587 /* We're leaving the context of this function, so zap cfun.
6588 It's still in DECL_STRUCT_FUNCTION, and we'll restore it in
6589 tree_rest_of_compilation. */
6591 current_function_decl = NULL;
6594 /* Generate the RTL for the body of FNDECL. */
6597 c_expand_body (tree fndecl)
6600 if (!DECL_INITIAL (fndecl)
6601 || DECL_INITIAL (fndecl) == error_mark_node)
6604 tree_rest_of_compilation (fndecl);
6606 if (DECL_STATIC_CONSTRUCTOR (fndecl)
6607 && targetm.have_ctors_dtors)
6608 targetm.asm_out.constructor (XEXP (DECL_RTL (fndecl), 0),
6609 DEFAULT_INIT_PRIORITY);
6610 if (DECL_STATIC_DESTRUCTOR (fndecl)
6611 && targetm.have_ctors_dtors)
6612 targetm.asm_out.destructor (XEXP (DECL_RTL (fndecl), 0),
6613 DEFAULT_INIT_PRIORITY);
6616 /* Check the declarations given in a for-loop for satisfying the C99
6619 check_for_loop_decls (void)
6621 struct c_binding *b;
6625 /* If we get here, declarations have been used in a for loop without
6626 the C99 for loop scope. This doesn't make much sense, so don't
6628 error ("%<for%> loop initial declaration used outside C99 mode");
6631 /* C99 subclause 6.8.5 paragraph 3:
6633 [#3] The declaration part of a for statement shall only
6634 declare identifiers for objects having storage class auto or
6637 It isn't clear whether, in this sentence, "identifiers" binds to
6638 "shall only declare" or to "objects" - that is, whether all identifiers
6639 declared must be identifiers for objects, or whether the restriction
6640 only applies to those that are. (A question on this in comp.std.c
6641 in November 2000 received no answer.) We implement the strictest
6642 interpretation, to avoid creating an extension which later causes
6645 for (b = current_scope->bindings; b; b = b->prev)
6648 tree decl = b->decl;
6653 switch (TREE_CODE (decl))
6656 if (TREE_STATIC (decl))
6657 error ("declaration of static variable %q+D in %<for%> loop "
6658 "initial declaration", decl);
6659 else if (DECL_EXTERNAL (decl))
6660 error ("declaration of %<extern%> variable %q+D in %<for%> loop "
6661 "initial declaration", decl);
6665 error ("%<struct %E%> declared in %<for%> loop initial declaration",
6669 error ("%<union %E%> declared in %<for%> loop initial declaration",
6673 error ("%<enum %E%> declared in %<for%> loop initial declaration",
6677 error ("declaration of non-variable %q+D in %<for%> loop "
6678 "initial declaration", decl);
6683 /* Save and reinitialize the variables
6684 used during compilation of a C function. */
6687 c_push_function_context (struct function *f)
6689 struct language_function *p;
6690 p = GGC_NEW (struct language_function);
6693 p->base.x_stmt_tree = c_stmt_tree;
6694 p->x_break_label = c_break_label;
6695 p->x_cont_label = c_cont_label;
6696 p->x_switch_stack = c_switch_stack;
6697 p->arg_info = current_function_arg_info;
6698 p->returns_value = current_function_returns_value;
6699 p->returns_null = current_function_returns_null;
6700 p->returns_abnormally = current_function_returns_abnormally;
6701 p->warn_about_return_type = warn_about_return_type;
6702 p->extern_inline = current_extern_inline;
6705 /* Restore the variables used during compilation of a C function. */
6708 c_pop_function_context (struct function *f)
6710 struct language_function *p = f->language;
6712 if (DECL_STRUCT_FUNCTION (current_function_decl) == 0
6713 && DECL_SAVED_TREE (current_function_decl) == NULL_TREE)
6715 /* Stop pointing to the local nodes about to be freed. */
6716 /* But DECL_INITIAL must remain nonzero so we know this
6717 was an actual function definition. */
6718 DECL_INITIAL (current_function_decl) = error_mark_node;
6719 DECL_ARGUMENTS (current_function_decl) = 0;
6722 c_stmt_tree = p->base.x_stmt_tree;
6723 c_break_label = p->x_break_label;
6724 c_cont_label = p->x_cont_label;
6725 c_switch_stack = p->x_switch_stack;
6726 current_function_arg_info = p->arg_info;
6727 current_function_returns_value = p->returns_value;
6728 current_function_returns_null = p->returns_null;
6729 current_function_returns_abnormally = p->returns_abnormally;
6730 warn_about_return_type = p->warn_about_return_type;
6731 current_extern_inline = p->extern_inline;
6736 /* Copy the DECL_LANG_SPECIFIC data associated with DECL. */
6739 c_dup_lang_specific_decl (tree decl)
6741 struct lang_decl *ld;
6743 if (!DECL_LANG_SPECIFIC (decl))
6746 ld = GGC_NEW (struct lang_decl);
6747 memcpy (ld, DECL_LANG_SPECIFIC (decl), sizeof (struct lang_decl));
6748 DECL_LANG_SPECIFIC (decl) = ld;
6751 /* The functions below are required for functionality of doing
6752 function at once processing in the C front end. Currently these
6753 functions are not called from anywhere in the C front end, but as
6754 these changes continue, that will change. */
6756 /* Returns the stmt_tree (if any) to which statements are currently
6757 being added. If there is no active statement-tree, NULL is
6761 current_stmt_tree (void)
6763 return &c_stmt_tree;
6766 /* Nonzero if TYPE is an anonymous union or struct type. Always 0 in
6770 anon_aggr_type_p (tree ARG_UNUSED (node))
6775 /* Return the global value of T as a symbol. */
6778 identifier_global_value (tree t)
6780 struct c_binding *b;
6782 for (b = I_SYMBOL_BINDING (t); b; b = b->shadowed)
6783 if (B_IN_FILE_SCOPE (b) || B_IN_EXTERNAL_SCOPE (b))
6789 /* Record a builtin type for C. If NAME is non-NULL, it is the name used;
6790 otherwise the name is found in ridpointers from RID_INDEX. */
6793 record_builtin_type (enum rid rid_index, const char *name, tree type)
6797 id = ridpointers[(int) rid_index];
6799 id = get_identifier (name);
6800 decl = build_decl (TYPE_DECL, id, type);
6802 if (debug_hooks->type_decl)
6803 debug_hooks->type_decl (decl, false);
6806 /* Build the void_list_node (void_type_node having been created). */
6808 build_void_list_node (void)
6810 tree t = build_tree_list (NULL_TREE, void_type_node);
6814 /* Return a c_parm structure with the given SPECS, ATTRS and DECLARATOR. */
6817 build_c_parm (struct c_declspecs *specs, tree attrs,
6818 struct c_declarator *declarator)
6820 struct c_parm *ret = XOBNEW (&parser_obstack, struct c_parm);
6823 ret->declarator = declarator;
6827 /* Return a declarator with nested attributes. TARGET is the inner
6828 declarator to which these attributes apply. ATTRS are the
6831 struct c_declarator *
6832 build_attrs_declarator (tree attrs, struct c_declarator *target)
6834 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
6835 ret->kind = cdk_attrs;
6836 ret->declarator = target;
6837 ret->u.attrs = attrs;
6841 /* Return a declarator for a function with arguments specified by ARGS
6842 and return type specified by TARGET. */
6844 struct c_declarator *
6845 build_function_declarator (struct c_arg_info *args,
6846 struct c_declarator *target)
6848 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
6849 ret->kind = cdk_function;
6850 ret->declarator = target;
6851 ret->u.arg_info = args;
6855 /* Return a declarator for the identifier IDENT (which may be
6856 NULL_TREE for an abstract declarator). */
6858 struct c_declarator *
6859 build_id_declarator (tree ident)
6861 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
6863 ret->declarator = 0;
6865 /* Default value - may get reset to a more precise location. */
6866 ret->id_loc = input_location;
6870 /* Return something to represent absolute declarators containing a *.
6871 TARGET is the absolute declarator that the * contains.
6872 TYPE_QUALS_ATTRS is a structure for type qualifiers and attributes
6873 to apply to the pointer type. */
6875 struct c_declarator *
6876 make_pointer_declarator (struct c_declspecs *type_quals_attrs,
6877 struct c_declarator *target)
6881 struct c_declarator *itarget = target;
6882 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
6883 if (type_quals_attrs)
6885 attrs = type_quals_attrs->attrs;
6886 quals = quals_from_declspecs (type_quals_attrs);
6887 if (attrs != NULL_TREE)
6888 itarget = build_attrs_declarator (attrs, target);
6890 ret->kind = cdk_pointer;
6891 ret->declarator = itarget;
6892 ret->u.pointer_quals = quals;
6896 /* Return a pointer to a structure for an empty list of declaration
6899 struct c_declspecs *
6900 build_null_declspecs (void)
6902 struct c_declspecs *ret = XOBNEW (&parser_obstack, struct c_declspecs);
6906 ret->typespec_word = cts_none;
6907 ret->storage_class = csc_none;
6908 ret->declspecs_seen_p = false;
6909 ret->type_seen_p = false;
6910 ret->non_sc_seen_p = false;
6911 ret->typedef_p = false;
6912 ret->tag_defined_p = false;
6913 ret->explicit_signed_p = false;
6914 ret->deprecated_p = false;
6915 ret->default_int_p = false;
6916 ret->long_p = false;
6917 ret->long_long_p = false;
6918 ret->short_p = false;
6919 ret->signed_p = false;
6920 ret->unsigned_p = false;
6921 ret->complex_p = false;
6922 ret->inline_p = false;
6923 ret->thread_p = false;
6924 ret->const_p = false;
6925 ret->volatile_p = false;
6926 ret->restrict_p = false;
6930 /* Add the type qualifier QUAL to the declaration specifiers SPECS,
6933 struct c_declspecs *
6934 declspecs_add_qual (struct c_declspecs *specs, tree qual)
6938 specs->non_sc_seen_p = true;
6939 specs->declspecs_seen_p = true;
6940 gcc_assert (TREE_CODE (qual) == IDENTIFIER_NODE
6941 && C_IS_RESERVED_WORD (qual));
6942 i = C_RID_CODE (qual);
6946 dupe = specs->const_p;
6947 specs->const_p = true;
6950 dupe = specs->volatile_p;
6951 specs->volatile_p = true;
6954 dupe = specs->restrict_p;
6955 specs->restrict_p = true;
6960 if (dupe && pedantic && !flag_isoc99)
6961 pedwarn ("duplicate %qE", qual);
6965 /* Add the type specifier TYPE to the declaration specifiers SPECS,
6968 struct c_declspecs *
6969 declspecs_add_type (struct c_declspecs *specs, struct c_typespec spec)
6971 tree type = spec.spec;
6972 specs->non_sc_seen_p = true;
6973 specs->declspecs_seen_p = true;
6974 specs->type_seen_p = true;
6975 if (TREE_DEPRECATED (type))
6976 specs->deprecated_p = true;
6978 /* Handle type specifier keywords. */
6979 if (TREE_CODE (type) == IDENTIFIER_NODE && C_IS_RESERVED_WORD (type))
6981 enum rid i = C_RID_CODE (type);
6984 error ("two or more data types in declaration specifiers");
6987 if ((int) i <= (int) RID_LAST_MODIFIER)
6989 /* "long", "short", "signed", "unsigned" or "_Complex". */
6994 if (specs->long_long_p)
6996 error ("%<long long long%> is too long for GCC");
7001 if (specs->typespec_word == cts_double)
7003 error ("both %<long long%> and %<double%> in "
7004 "declaration specifiers");
7007 if (pedantic && !flag_isoc99 && !in_system_header
7009 pedwarn ("ISO C90 does not support %<long long%>");
7010 specs->long_long_p = 1;
7014 error ("both %<long%> and %<short%> in "
7015 "declaration specifiers");
7016 else if (specs->typespec_word == cts_void)
7017 error ("both %<long%> and %<void%> in "
7018 "declaration specifiers");
7019 else if (specs->typespec_word == cts_bool)
7020 error ("both %<long%> and %<_Bool%> in "
7021 "declaration specifiers");
7022 else if (specs->typespec_word == cts_char)
7023 error ("both %<long%> and %<char%> in "
7024 "declaration specifiers");
7025 else if (specs->typespec_word == cts_float)
7026 error ("both %<long%> and %<float%> in "
7027 "declaration specifiers");
7029 specs->long_p = true;
7032 dupe = specs->short_p;
7034 error ("both %<long%> and %<short%> in "
7035 "declaration specifiers");
7036 else if (specs->typespec_word == cts_void)
7037 error ("both %<short%> and %<void%> in "
7038 "declaration specifiers");
7039 else if (specs->typespec_word == cts_bool)
7040 error ("both %<short%> and %<_Bool%> in "
7041 "declaration specifiers");
7042 else if (specs->typespec_word == cts_char)
7043 error ("both %<short%> and %<char%> in "
7044 "declaration specifiers");
7045 else if (specs->typespec_word == cts_float)
7046 error ("both %<short%> and %<float%> in "
7047 "declaration specifiers");
7048 else if (specs->typespec_word == cts_double)
7049 error ("both %<short%> and %<double%> in "
7050 "declaration specifiers");
7052 specs->short_p = true;
7055 dupe = specs->signed_p;
7056 if (specs->unsigned_p)
7057 error ("both %<signed%> and %<unsigned%> in "
7058 "declaration specifiers");
7059 else if (specs->typespec_word == cts_void)
7060 error ("both %<signed%> and %<void%> in "
7061 "declaration specifiers");
7062 else if (specs->typespec_word == cts_bool)
7063 error ("both %<signed%> and %<_Bool%> in "
7064 "declaration specifiers");
7065 else if (specs->typespec_word == cts_float)
7066 error ("both %<signed%> and %<float%> in "
7067 "declaration specifiers");
7068 else if (specs->typespec_word == cts_double)
7069 error ("both %<signed%> and %<double%> in "
7070 "declaration specifiers");
7072 specs->signed_p = true;
7075 dupe = specs->unsigned_p;
7076 if (specs->signed_p)
7077 error ("both %<signed%> and %<unsigned%> in "
7078 "declaration specifiers");
7079 else if (specs->typespec_word == cts_void)
7080 error ("both %<unsigned%> and %<void%> in "
7081 "declaration specifiers");
7082 else if (specs->typespec_word == cts_bool)
7083 error ("both %<unsigned%> and %<_Bool%> in "
7084 "declaration specifiers");
7085 else if (specs->typespec_word == cts_float)
7086 error ("both %<unsigned%> and %<float%> in "
7087 "declaration specifiers");
7088 else if (specs->typespec_word == cts_double)
7089 error ("both %<unsigned%> and %<double%> in "
7090 "declaration specifiers");
7092 specs->unsigned_p = true;
7095 dupe = specs->complex_p;
7096 if (pedantic && !flag_isoc99 && !in_system_header)
7097 pedwarn ("ISO C90 does not support complex types");
7098 if (specs->typespec_word == cts_void)
7099 error ("both %<complex%> and %<void%> in "
7100 "declaration specifiers");
7101 else if (specs->typespec_word == cts_bool)
7102 error ("both %<complex%> and %<_Bool%> in "
7103 "declaration specifiers");
7105 specs->complex_p = true;
7112 error ("duplicate %qE", type);
7118 /* "void", "_Bool", "char", "int", "float" or "double". */
7119 if (specs->typespec_word != cts_none)
7121 error ("two or more data types in declaration specifiers");
7128 error ("both %<long%> and %<void%> in "
7129 "declaration specifiers");
7130 else if (specs->short_p)
7131 error ("both %<short%> and %<void%> in "
7132 "declaration specifiers");
7133 else if (specs->signed_p)
7134 error ("both %<signed%> and %<void%> in "
7135 "declaration specifiers");
7136 else if (specs->unsigned_p)
7137 error ("both %<unsigned%> and %<void%> in "
7138 "declaration specifiers");
7139 else if (specs->complex_p)
7140 error ("both %<complex%> and %<void%> in "
7141 "declaration specifiers");
7143 specs->typespec_word = cts_void;
7147 error ("both %<long%> and %<_Bool%> in "
7148 "declaration specifiers");
7149 else if (specs->short_p)
7150 error ("both %<short%> and %<_Bool%> in "
7151 "declaration specifiers");
7152 else if (specs->signed_p)
7153 error ("both %<signed%> and %<_Bool%> in "
7154 "declaration specifiers");
7155 else if (specs->unsigned_p)
7156 error ("both %<unsigned%> and %<_Bool%> in "
7157 "declaration specifiers");
7158 else if (specs->complex_p)
7159 error ("both %<complex%> and %<_Bool%> in "
7160 "declaration specifiers");
7162 specs->typespec_word = cts_bool;
7166 error ("both %<long%> and %<char%> in "
7167 "declaration specifiers");
7168 else if (specs->short_p)
7169 error ("both %<short%> and %<char%> in "
7170 "declaration specifiers");
7172 specs->typespec_word = cts_char;
7175 specs->typespec_word = cts_int;
7179 error ("both %<long%> and %<float%> in "
7180 "declaration specifiers");
7181 else if (specs->short_p)
7182 error ("both %<short%> and %<float%> in "
7183 "declaration specifiers");
7184 else if (specs->signed_p)
7185 error ("both %<signed%> and %<float%> in "
7186 "declaration specifiers");
7187 else if (specs->unsigned_p)
7188 error ("both %<unsigned%> and %<float%> in "
7189 "declaration specifiers");
7191 specs->typespec_word = cts_float;
7194 if (specs->long_long_p)
7195 error ("both %<long long%> and %<double%> in "
7196 "declaration specifiers");
7197 else if (specs->short_p)
7198 error ("both %<short%> and %<double%> in "
7199 "declaration specifiers");
7200 else if (specs->signed_p)
7201 error ("both %<signed%> and %<double%> in "
7202 "declaration specifiers");
7203 else if (specs->unsigned_p)
7204 error ("both %<unsigned%> and %<double%> in "
7205 "declaration specifiers");
7207 specs->typespec_word = cts_double;
7210 /* ObjC reserved word "id", handled below. */
7216 /* Now we have a typedef (a TYPE_DECL node), an identifier (some
7217 form of ObjC type, cases such as "int" and "long" being handled
7218 above), a TYPE (struct, union, enum and typeof specifiers) or an
7219 ERROR_MARK. In none of these cases may there have previously
7220 been any type specifiers. */
7221 if (specs->type || specs->typespec_word != cts_none
7222 || specs->long_p || specs->short_p || specs->signed_p
7223 || specs->unsigned_p || specs->complex_p)
7224 error ("two or more data types in declaration specifiers");
7225 else if (TREE_CODE (type) == TYPE_DECL)
7227 if (TREE_TYPE (type) == error_mark_node)
7228 ; /* Allow the type to default to int to avoid cascading errors. */
7231 specs->type = TREE_TYPE (type);
7232 specs->decl_attr = DECL_ATTRIBUTES (type);
7233 specs->typedef_p = true;
7234 specs->explicit_signed_p = C_TYPEDEF_EXPLICITLY_SIGNED (type);
7237 else if (TREE_CODE (type) == IDENTIFIER_NODE)
7239 tree t = lookup_name (type);
7240 if (!t || TREE_CODE (t) != TYPE_DECL)
7241 error ("%qE fails to be a typedef or built in type", type);
7242 else if (TREE_TYPE (t) == error_mark_node)
7245 specs->type = TREE_TYPE (t);
7247 else if (TREE_CODE (type) != ERROR_MARK)
7249 if (spec.kind == ctsk_tagdef || spec.kind == ctsk_tagfirstref)
7250 specs->tag_defined_p = true;
7251 if (spec.kind == ctsk_typeof)
7252 specs->typedef_p = true;
7259 /* Add the storage class specifier or function specifier SCSPEC to the
7260 declaration specifiers SPECS, returning SPECS. */
7262 struct c_declspecs *
7263 declspecs_add_scspec (struct c_declspecs *specs, tree scspec)
7266 enum c_storage_class n = csc_none;
7268 specs->declspecs_seen_p = true;
7269 gcc_assert (TREE_CODE (scspec) == IDENTIFIER_NODE
7270 && C_IS_RESERVED_WORD (scspec));
7271 i = C_RID_CODE (scspec);
7272 if (extra_warnings && specs->non_sc_seen_p)
7273 warning (OPT_Wextra, "%qE is not at beginning of declaration", scspec);
7277 /* C99 permits duplicate inline. Although of doubtful utility,
7278 it seems simplest to permit it in gnu89 mode as well, as
7279 there is also little utility in maintaining this as a
7280 difference between gnu89 and C99 inline. */
7282 specs->inline_p = true;
7285 dupe = specs->thread_p;
7286 if (specs->storage_class == csc_auto)
7287 error ("%<__thread%> used with %<auto%>");
7288 else if (specs->storage_class == csc_register)
7289 error ("%<__thread%> used with %<register%>");
7290 else if (specs->storage_class == csc_typedef)
7291 error ("%<__thread%> used with %<typedef%>");
7293 specs->thread_p = true;
7300 /* Diagnose "__thread extern". */
7301 if (specs->thread_p)
7302 error ("%<__thread%> before %<extern%>");
7309 /* Diagnose "__thread static". */
7310 if (specs->thread_p)
7311 error ("%<__thread%> before %<static%>");
7319 if (n != csc_none && n == specs->storage_class)
7322 error ("duplicate %qE", scspec);
7325 if (specs->storage_class != csc_none && n != specs->storage_class)
7327 error ("multiple storage classes in declaration specifiers");
7331 specs->storage_class = n;
7332 if (n != csc_extern && n != csc_static && specs->thread_p)
7334 error ("%<__thread%> used with %qE", scspec);
7335 specs->thread_p = false;
7342 /* Add the attributes ATTRS to the declaration specifiers SPECS,
7345 struct c_declspecs *
7346 declspecs_add_attrs (struct c_declspecs *specs, tree attrs)
7348 specs->attrs = chainon (attrs, specs->attrs);
7349 specs->declspecs_seen_p = true;
7353 /* Combine "long", "short", "signed", "unsigned" and "_Complex" type
7354 specifiers with any other type specifier to determine the resulting
7355 type. This is where ISO C checks on complex types are made, since
7356 "_Complex long" is a prefix of the valid ISO C type "_Complex long
7359 struct c_declspecs *
7360 finish_declspecs (struct c_declspecs *specs)
7362 /* If a type was specified as a whole, we have no modifiers and are
7364 if (specs->type != NULL_TREE)
7366 gcc_assert (!specs->long_p && !specs->long_long_p && !specs->short_p
7367 && !specs->signed_p && !specs->unsigned_p
7368 && !specs->complex_p);
7372 /* If none of "void", "_Bool", "char", "int", "float" or "double"
7373 has been specified, treat it as "int" unless "_Complex" is
7374 present and there are no other specifiers. If we just have
7375 "_Complex", it is equivalent to "_Complex double", but e.g.
7376 "_Complex short" is equivalent to "_Complex short int". */
7377 if (specs->typespec_word == cts_none)
7379 if (specs->long_p || specs->short_p
7380 || specs->signed_p || specs->unsigned_p)
7382 specs->typespec_word = cts_int;
7384 else if (specs->complex_p)
7386 specs->typespec_word = cts_double;
7388 pedwarn ("ISO C does not support plain %<complex%> meaning "
7389 "%<double complex%>");
7393 specs->typespec_word = cts_int;
7394 specs->default_int_p = true;
7395 /* We don't diagnose this here because grokdeclarator will
7396 give more specific diagnostics according to whether it is
7397 a function definition. */
7401 /* If "signed" was specified, record this to distinguish "int" and
7402 "signed int" in the case of a bit-field with
7403 -funsigned-bitfields. */
7404 specs->explicit_signed_p = specs->signed_p;
7406 /* Now compute the actual type. */
7407 switch (specs->typespec_word)
7410 gcc_assert (!specs->long_p && !specs->short_p
7411 && !specs->signed_p && !specs->unsigned_p
7412 && !specs->complex_p);
7413 specs->type = void_type_node;
7416 gcc_assert (!specs->long_p && !specs->short_p
7417 && !specs->signed_p && !specs->unsigned_p
7418 && !specs->complex_p);
7419 specs->type = boolean_type_node;
7422 gcc_assert (!specs->long_p && !specs->short_p);
7423 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7424 if (specs->signed_p)
7425 specs->type = signed_char_type_node;
7426 else if (specs->unsigned_p)
7427 specs->type = unsigned_char_type_node;
7429 specs->type = char_type_node;
7430 if (specs->complex_p)
7433 pedwarn ("ISO C does not support complex integer types");
7434 specs->type = build_complex_type (specs->type);
7438 gcc_assert (!(specs->long_p && specs->short_p));
7439 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7440 if (specs->long_long_p)
7441 specs->type = (specs->unsigned_p
7442 ? long_long_unsigned_type_node
7443 : long_long_integer_type_node);
7444 else if (specs->long_p)
7445 specs->type = (specs->unsigned_p
7446 ? long_unsigned_type_node
7447 : long_integer_type_node);
7448 else if (specs->short_p)
7449 specs->type = (specs->unsigned_p
7450 ? short_unsigned_type_node
7451 : short_integer_type_node);
7453 specs->type = (specs->unsigned_p
7454 ? unsigned_type_node
7455 : integer_type_node);
7456 if (specs->complex_p)
7459 pedwarn ("ISO C does not support complex integer types");
7460 specs->type = build_complex_type (specs->type);
7464 gcc_assert (!specs->long_p && !specs->short_p
7465 && !specs->signed_p && !specs->unsigned_p);
7466 specs->type = (specs->complex_p
7467 ? complex_float_type_node
7471 gcc_assert (!specs->long_long_p && !specs->short_p
7472 && !specs->signed_p && !specs->unsigned_p);
7475 specs->type = (specs->complex_p
7476 ? complex_long_double_type_node
7477 : long_double_type_node);
7481 specs->type = (specs->complex_p
7482 ? complex_double_type_node
7483 : double_type_node);
7493 /* Synthesize a function which calls all the global ctors or global
7494 dtors in this file. This is only used for targets which do not
7495 support .ctors/.dtors sections. FIXME: Migrate into cgraph. */
7497 build_cdtor (int method_type, tree cdtors)
7504 for (; cdtors; cdtors = TREE_CHAIN (cdtors))
7505 append_to_statement_list (build_function_call (TREE_VALUE (cdtors), 0),
7508 cgraph_build_static_cdtor (method_type, body, DEFAULT_INIT_PRIORITY);
7511 /* Perform final processing on one file scope's declarations (or the
7512 external scope's declarations), GLOBALS. */
7514 c_write_global_declarations_1 (tree globals)
7516 size_t len = list_length (globals);
7517 tree *vec = XNEWVEC (tree, len);
7521 /* Process the decls in the order they were written. */
7522 for (i = 0, decl = globals; i < len; i++, decl = TREE_CHAIN (decl))
7525 /* Check for used but undefined static functions using the C
7526 standard's definition of "used", and set TREE_NO_WARNING so
7527 that check_global_declarations doesn't repeat the check. */
7528 if (TREE_CODE (decl) == FUNCTION_DECL
7529 && DECL_INITIAL (decl) == 0
7530 && DECL_EXTERNAL (decl)
7531 && !TREE_PUBLIC (decl)
7532 && C_DECL_USED (decl))
7534 pedwarn ("%q+F used but never defined", decl);
7535 TREE_NO_WARNING (decl) = 1;
7539 wrapup_global_declarations (vec, len);
7540 check_global_declarations (vec, len);
7546 c_write_global_declarations (void)
7550 /* We don't want to do this if generating a PCH. */
7554 /* Don't waste time on further processing if -fsyntax-only or we've
7555 encountered errors. */
7556 if (flag_syntax_only || errorcount || sorrycount || cpp_errors (parse_in))
7559 /* Close the external scope. */
7560 ext_block = pop_scope ();
7562 gcc_assert (!current_scope);
7564 /* Process all file scopes in this compilation, and the external_scope,
7565 through wrapup_global_declarations and check_global_declarations. */
7566 for (t = all_translation_units; t; t = TREE_CHAIN (t))
7567 c_write_global_declarations_1 (BLOCK_VARS (DECL_INITIAL (t)));
7570 tree tmp = BLOCK_VARS (ext_block);
7572 FILE * stream = dump_begin (TDI_tu, &flags);
7575 dump_node (tmp, flags & ~TDF_SLIM, stream);
7576 dump_end (TDI_tu, stream);
7579 c_write_global_declarations_1 (BLOCK_VARS (ext_block));
7581 /* Generate functions to call static constructors and destructors
7582 for targets that do not support .ctors/.dtors sections. These
7583 functions have magic names which are detected by collect2. */
7584 build_cdtor ('I', static_ctors); static_ctors = 0;
7585 build_cdtor ('D', static_dtors); static_dtors = 0;
7587 /* We're done parsing; proceed to optimize and emit assembly.
7588 FIXME: shouldn't be the front end's responsibility to call this. */
7592 #include "gt-c-decl.h"