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 /* Set this to 1 if you want the standard ISO C99 semantics of 'inline'
66 when you specify -std=c99 or -std=gnu99, and to 0 if you want
67 behaviour compatible with the nonstandard semantics implemented by
68 GCC 2.95 through 4.2. */
69 #define WANT_C99_INLINE_SEMANTICS 1
71 /* In grokdeclarator, distinguish syntactic contexts of declarators. */
73 { NORMAL, /* Ordinary declaration */
74 FUNCDEF, /* Function definition */
75 PARM, /* Declaration of parm before function body */
76 FIELD, /* Declaration inside struct or union */
77 TYPENAME}; /* Typename (inside cast or sizeof) */
80 /* Nonzero if we have seen an invalid cross reference
81 to a struct, union, or enum, but not yet printed the message. */
82 tree pending_invalid_xref;
84 /* File and line to appear in the eventual error message. */
85 location_t pending_invalid_xref_location;
87 /* True means we've initialized exception handling. */
88 bool c_eh_initialized_p;
90 /* While defining an enum type, this is 1 plus the last enumerator
91 constant value. Note that will do not have to save this or `enum_overflow'
92 around nested function definition since such a definition could only
93 occur in an enum value expression and we don't use these variables in
96 static tree enum_next_value;
98 /* Nonzero means that there was overflow computing enum_next_value. */
100 static int enum_overflow;
102 /* The file and line that the prototype came from if this is an
103 old-style definition; used for diagnostics in
104 store_parm_decls_oldstyle. */
106 static location_t current_function_prototype_locus;
108 /* Whether this prototype was built-in. */
110 static bool current_function_prototype_built_in;
112 /* The argument type information of this prototype. */
114 static tree current_function_prototype_arg_types;
116 /* The argument information structure for the function currently being
119 static struct c_arg_info *current_function_arg_info;
121 /* The obstack on which parser and related data structures, which are
122 not live beyond their top-level declaration or definition, are
124 struct obstack parser_obstack;
126 /* The current statement tree. */
128 static GTY(()) struct stmt_tree_s c_stmt_tree;
130 /* State saving variables. */
134 /* Linked list of TRANSLATION_UNIT_DECLS for the translation units
135 included in this invocation. Note that the current translation
136 unit is not included in this list. */
138 static GTY(()) tree all_translation_units;
140 /* A list of decls to be made automatically visible in each file scope. */
141 static GTY(()) tree visible_builtins;
143 /* Set to 0 at beginning of a function definition, set to 1 if
144 a return statement that specifies a return value is seen. */
146 int current_function_returns_value;
148 /* Set to 0 at beginning of a function definition, set to 1 if
149 a return statement with no argument is seen. */
151 int current_function_returns_null;
153 /* Set to 0 at beginning of a function definition, set to 1 if
154 a call to a noreturn function is seen. */
156 int current_function_returns_abnormally;
158 /* Set to nonzero by `grokdeclarator' for a function
159 whose return type is defaulted, if warnings for this are desired. */
161 static int warn_about_return_type;
163 /* Nonzero when the current toplevel function contains a declaration
164 of a nested function which is never defined. */
166 static bool undef_nested_function;
168 /* True means global_bindings_p should return false even if the scope stack
169 says we are in file scope. */
170 bool c_override_global_bindings_to_false;
173 /* Each c_binding structure describes one binding of an identifier to
174 a decl. All the decls in a scope - irrespective of namespace - are
175 chained together by the ->prev field, which (as the name implies)
176 runs in reverse order. All the decls in a given namespace bound to
177 a given identifier are chained by the ->shadowed field, which runs
178 from inner to outer scopes.
180 The ->decl field usually points to a DECL node, but there are two
181 exceptions. In the namespace of type tags, the bound entity is a
182 RECORD_TYPE, UNION_TYPE, or ENUMERAL_TYPE node. If an undeclared
183 identifier is encountered, it is bound to error_mark_node to
184 suppress further errors about that identifier in the current
187 The ->type field stores the type of the declaration in this scope;
188 if NULL, the type is the type of the ->decl field. This is only of
189 relevance for objects with external or internal linkage which may
190 be redeclared in inner scopes, forming composite types that only
191 persist for the duration of those scopes. In the external scope,
192 this stores the composite of all the types declared for this
193 object, visible or not. The ->inner_comp field (used only at file
194 scope) stores whether an incomplete array type at file scope was
195 completed at an inner scope to an array size other than 1.
197 The depth field is copied from the scope structure that holds this
198 decl. It is used to preserve the proper ordering of the ->shadowed
199 field (see bind()) and also for a handful of special-case checks.
200 Finally, the invisible bit is true for a decl which should be
201 ignored for purposes of normal name lookup, and the nested bit is
202 true for a decl that's been bound a second time in an inner scope;
203 in all such cases, the binding in the outer scope will have its
204 invisible bit true. */
206 struct c_binding GTY((chain_next ("%h.prev")))
208 tree decl; /* the decl bound */
209 tree type; /* the type in this scope */
210 tree id; /* the identifier it's bound to */
211 struct c_binding *prev; /* the previous decl in this scope */
212 struct c_binding *shadowed; /* the innermost decl shadowed by this one */
213 unsigned int depth : 28; /* depth of this scope */
214 BOOL_BITFIELD invisible : 1; /* normal lookup should ignore this binding */
215 BOOL_BITFIELD nested : 1; /* do not set DECL_CONTEXT when popping */
216 BOOL_BITFIELD inner_comp : 1; /* incomplete array completed in inner scope */
219 #define B_IN_SCOPE(b1, b2) ((b1)->depth == (b2)->depth)
220 #define B_IN_CURRENT_SCOPE(b) ((b)->depth == current_scope->depth)
221 #define B_IN_FILE_SCOPE(b) ((b)->depth == 1 /*file_scope->depth*/)
222 #define B_IN_EXTERNAL_SCOPE(b) ((b)->depth == 0 /*external_scope->depth*/)
224 #define I_SYMBOL_BINDING(node) \
225 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->symbol_binding)
226 #define I_SYMBOL_DECL(node) \
227 (I_SYMBOL_BINDING(node) ? I_SYMBOL_BINDING(node)->decl : 0)
229 #define I_TAG_BINDING(node) \
230 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->tag_binding)
231 #define I_TAG_DECL(node) \
232 (I_TAG_BINDING(node) ? I_TAG_BINDING(node)->decl : 0)
234 #define I_LABEL_BINDING(node) \
235 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->label_binding)
236 #define I_LABEL_DECL(node) \
237 (I_LABEL_BINDING(node) ? I_LABEL_BINDING(node)->decl : 0)
239 /* Each C symbol points to three linked lists of c_binding structures.
240 These describe the values of the identifier in the three different
241 namespaces defined by the language. */
243 struct lang_identifier GTY(())
245 struct c_common_identifier common_id;
246 struct c_binding *symbol_binding; /* vars, funcs, constants, typedefs */
247 struct c_binding *tag_binding; /* struct/union/enum tags */
248 struct c_binding *label_binding; /* labels */
251 /* Validate c-lang.c's assumptions. */
252 extern char C_SIZEOF_STRUCT_LANG_IDENTIFIER_isnt_accurate
253 [(sizeof(struct lang_identifier) == C_SIZEOF_STRUCT_LANG_IDENTIFIER) ? 1 : -1];
255 /* The resulting tree type. */
258 GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE"),
259 chain_next ("TREE_CODE (&%h.generic) == INTEGER_TYPE ? (union lang_tree_node *) TYPE_NEXT_VARIANT (&%h.generic) : (GIMPLE_TUPLE_P (&%h.generic) ? (union lang_tree_node *) 0 : (union lang_tree_node *) TREE_CHAIN (&%h.generic))")))
261 union tree_node GTY ((tag ("0"),
262 desc ("tree_node_structure (&%h)")))
264 struct lang_identifier GTY ((tag ("1"))) identifier;
267 /* Each c_scope structure describes the complete contents of one
268 scope. Four scopes are distinguished specially: the innermost or
269 current scope, the innermost function scope, the file scope (always
270 the second to outermost) and the outermost or external scope.
272 Most declarations are recorded in the current scope.
274 All normal label declarations are recorded in the innermost
275 function scope, as are bindings of undeclared identifiers to
276 error_mark_node. (GCC permits nested functions as an extension,
277 hence the 'innermost' qualifier.) Explicitly declared labels
278 (using the __label__ extension) appear in the current scope.
280 Being in the file scope (current_scope == file_scope) causes
281 special behavior in several places below. Also, under some
282 conditions the Objective-C front end records declarations in the
283 file scope even though that isn't the current scope.
285 All declarations with external linkage are recorded in the external
286 scope, even if they aren't visible there; this models the fact that
287 such declarations are visible to the entire program, and (with a
288 bit of cleverness, see pushdecl) allows diagnosis of some violations
289 of C99 6.2.2p7 and 6.2.7p2:
291 If, within the same translation unit, the same identifier appears
292 with both internal and external linkage, the behavior is
295 All declarations that refer to the same object or function shall
296 have compatible type; otherwise, the behavior is undefined.
298 Initially only the built-in declarations, which describe compiler
299 intrinsic functions plus a subset of the standard library, are in
302 The order of the blocks list matters, and it is frequently appended
303 to. To avoid having to walk all the way to the end of the list on
304 each insertion, or reverse the list later, we maintain a pointer to
305 the last list entry. (FIXME: It should be feasible to use a reversed
308 The bindings list is strictly in reverse order of declarations;
309 pop_scope relies on this. */
312 struct c_scope GTY((chain_next ("%h.outer")))
314 /* The scope containing this one. */
315 struct c_scope *outer;
317 /* The next outermost function scope. */
318 struct c_scope *outer_function;
320 /* All bindings in this scope. */
321 struct c_binding *bindings;
323 /* For each scope (except the global one), a chain of BLOCK nodes
324 for all the scopes that were entered and exited one level down. */
328 /* The depth of this scope. Used to keep the ->shadowed chain of
329 bindings sorted innermost to outermost. */
330 unsigned int depth : 28;
332 /* True if we are currently filling this scope with parameter
334 BOOL_BITFIELD parm_flag : 1;
336 /* True if we saw [*] in this scope. Used to give an error messages
337 if these appears in a function definition. */
338 BOOL_BITFIELD had_vla_unspec : 1;
340 /* True if we already complained about forward parameter decls
341 in this scope. This prevents double warnings on
342 foo (int a; int b; ...) */
343 BOOL_BITFIELD warned_forward_parm_decls : 1;
345 /* True if this is the outermost block scope of a function body.
346 This scope contains the parameters, the local variables declared
347 in the outermost block, and all the labels (except those in
348 nested functions, or declared at block scope with __label__). */
349 BOOL_BITFIELD function_body : 1;
351 /* True means make a BLOCK for this scope no matter what. */
352 BOOL_BITFIELD keep : 1;
355 /* The scope currently in effect. */
357 static GTY(()) struct c_scope *current_scope;
359 /* The innermost function scope. Ordinary (not explicitly declared)
360 labels, bindings to error_mark_node, and the lazily-created
361 bindings of __func__ and its friends get this scope. */
363 static GTY(()) struct c_scope *current_function_scope;
365 /* The C file scope. This is reset for each input translation unit. */
367 static GTY(()) struct c_scope *file_scope;
369 /* The outermost scope. This is used for all declarations with
370 external linkage, and only these, hence the name. */
372 static GTY(()) struct c_scope *external_scope;
374 /* A chain of c_scope structures awaiting reuse. */
376 static GTY((deletable)) struct c_scope *scope_freelist;
378 /* A chain of c_binding structures awaiting reuse. */
380 static GTY((deletable)) struct c_binding *binding_freelist;
382 /* Append VAR to LIST in scope SCOPE. */
383 #define SCOPE_LIST_APPEND(scope, list, decl) do { \
384 struct c_scope *s_ = (scope); \
386 if (s_->list##_last) \
387 TREE_CHAIN (s_->list##_last) = d_; \
390 s_->list##_last = d_; \
393 /* Concatenate FROM in scope FSCOPE onto TO in scope TSCOPE. */
394 #define SCOPE_LIST_CONCAT(tscope, to, fscope, from) do { \
395 struct c_scope *t_ = (tscope); \
396 struct c_scope *f_ = (fscope); \
398 TREE_CHAIN (t_->to##_last) = f_->from; \
401 t_->to##_last = f_->from##_last; \
404 /* True means unconditionally make a BLOCK for the next scope pushed. */
406 static bool keep_next_level_flag;
408 /* True means the next call to push_scope will be the outermost scope
409 of a function body, so do not push a new scope, merely cease
410 expecting parameter decls. */
412 static bool next_is_function_body;
414 /* Functions called automatically at the beginning and end of execution. */
416 static GTY(()) tree static_ctors;
417 static GTY(()) tree static_dtors;
419 /* Forward declarations. */
420 static tree lookup_name_in_scope (tree, struct c_scope *);
421 static tree c_make_fname_decl (tree, int);
422 static tree grokdeclarator (const struct c_declarator *,
423 struct c_declspecs *,
424 enum decl_context, bool, tree *);
425 static tree grokparms (struct c_arg_info *, bool);
426 static void layout_array_type (tree);
428 /* T is a statement. Add it to the statement-tree. This is the
429 C/ObjC version--C++ has a slightly different version of this
435 enum tree_code code = TREE_CODE (t);
437 if (CAN_HAVE_LOCATION_P (t) && code != LABEL_EXPR)
439 if (!EXPR_HAS_LOCATION (t))
440 SET_EXPR_LOCATION (t, input_location);
443 if (code == LABEL_EXPR || code == CASE_LABEL_EXPR)
444 STATEMENT_LIST_HAS_LABEL (cur_stmt_list) = 1;
446 /* Add T to the statement-tree. Non-side-effect statements need to be
447 recorded during statement expressions. */
448 append_to_statement_list_force (t, &cur_stmt_list);
453 /* States indicating how grokdeclarator() should handle declspecs marked
454 with __attribute__((deprecated)). An object declared as
455 __attribute__((deprecated)) suppresses warnings of uses of other
458 enum deprecated_states {
463 static enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
466 c_print_identifier (FILE *file, tree node, int indent)
468 print_node (file, "symbol", I_SYMBOL_DECL (node), indent + 4);
469 print_node (file, "tag", I_TAG_DECL (node), indent + 4);
470 print_node (file, "label", I_LABEL_DECL (node), indent + 4);
471 if (C_IS_RESERVED_WORD (node))
473 tree rid = ridpointers[C_RID_CODE (node)];
474 indent_to (file, indent + 4);
475 fprintf (file, "rid %p \"%s\"",
476 (void *) rid, IDENTIFIER_POINTER (rid));
480 /* Establish a binding between NAME, an IDENTIFIER_NODE, and DECL,
481 which may be any of several kinds of DECL or TYPE or error_mark_node,
482 in the scope SCOPE. */
484 bind (tree name, tree decl, struct c_scope *scope, bool invisible, bool nested)
486 struct c_binding *b, **here;
488 if (binding_freelist)
490 b = binding_freelist;
491 binding_freelist = b->prev;
494 b = GGC_NEW (struct c_binding);
499 b->depth = scope->depth;
500 b->invisible = invisible;
506 b->prev = scope->bindings;
512 switch (TREE_CODE (decl))
514 case LABEL_DECL: here = &I_LABEL_BINDING (name); break;
517 case RECORD_TYPE: here = &I_TAG_BINDING (name); break;
523 case ERROR_MARK: here = &I_SYMBOL_BINDING (name); break;
529 /* Locate the appropriate place in the chain of shadowed decls
530 to insert this binding. Normally, scope == current_scope and
531 this does nothing. */
532 while (*here && (*here)->depth > scope->depth)
533 here = &(*here)->shadowed;
539 /* Clear the binding structure B, stick it on the binding_freelist,
540 and return the former value of b->prev. This is used by pop_scope
541 and get_parm_info to iterate destructively over all the bindings
542 from a given scope. */
543 static struct c_binding *
544 free_binding_and_advance (struct c_binding *b)
546 struct c_binding *prev = b->prev;
548 memset (b, 0, sizeof (struct c_binding));
549 b->prev = binding_freelist;
550 binding_freelist = b;
556 /* Hook called at end of compilation to assume 1 elt
557 for a file-scope tentative array defn that wasn't complete before. */
560 c_finish_incomplete_decl (tree decl)
562 if (TREE_CODE (decl) == VAR_DECL)
564 tree type = TREE_TYPE (decl);
565 if (type != error_mark_node
566 && TREE_CODE (type) == ARRAY_TYPE
567 && !DECL_EXTERNAL (decl)
568 && TYPE_DOMAIN (type) == 0)
570 warning (0, "array %q+D assumed to have one element", decl);
572 complete_array_type (&TREE_TYPE (decl), NULL_TREE, true);
574 layout_decl (decl, 0);
579 /* The Objective-C front-end often needs to determine the current scope. */
582 objc_get_current_scope (void)
584 return current_scope;
587 /* The following function is used only by Objective-C. It needs to live here
588 because it accesses the innards of c_scope. */
591 objc_mark_locals_volatile (void *enclosing_blk)
593 struct c_scope *scope;
596 for (scope = current_scope;
597 scope && scope != enclosing_blk;
598 scope = scope->outer)
600 for (b = scope->bindings; b; b = b->prev)
601 objc_volatilize_decl (b->decl);
603 /* Do not climb up past the current function. */
604 if (scope->function_body)
609 /* Nonzero if we are currently in file scope. */
612 global_bindings_p (void)
614 return current_scope == file_scope && !c_override_global_bindings_to_false;
618 keep_next_level (void)
620 keep_next_level_flag = true;
623 /* Identify this scope as currently being filled with parameters. */
626 declare_parm_level (void)
628 current_scope->parm_flag = true;
634 if (next_is_function_body)
636 /* This is the transition from the parameters to the top level
637 of the function body. These are the same scope
638 (C99 6.2.1p4,6) so we do not push another scope structure.
639 next_is_function_body is set only by store_parm_decls, which
640 in turn is called when and only when we are about to
641 encounter the opening curly brace for the function body.
643 The outermost block of a function always gets a BLOCK node,
644 because the debugging output routines expect that each
645 function has at least one BLOCK. */
646 current_scope->parm_flag = false;
647 current_scope->function_body = true;
648 current_scope->keep = true;
649 current_scope->outer_function = current_function_scope;
650 current_function_scope = current_scope;
652 keep_next_level_flag = false;
653 next_is_function_body = false;
657 struct c_scope *scope;
660 scope = scope_freelist;
661 scope_freelist = scope->outer;
664 scope = GGC_CNEW (struct c_scope);
666 scope->keep = keep_next_level_flag;
667 scope->outer = current_scope;
668 scope->depth = current_scope ? (current_scope->depth + 1) : 0;
670 /* Check for scope depth overflow. Unlikely (2^28 == 268,435,456) but
672 if (current_scope && scope->depth == 0)
675 sorry ("GCC supports only %u nested scopes", scope->depth);
678 current_scope = scope;
679 keep_next_level_flag = false;
683 /* Set the TYPE_CONTEXT of all of TYPE's variants to CONTEXT. */
686 set_type_context (tree type, tree context)
688 for (type = TYPE_MAIN_VARIANT (type); type;
689 type = TYPE_NEXT_VARIANT (type))
690 TYPE_CONTEXT (type) = context;
693 /* Exit a scope. Restore the state of the identifier-decl mappings
694 that were in effect when this scope was entered. Return a BLOCK
695 node containing all the DECLs in this scope that are of interest
696 to debug info generation. */
701 struct c_scope *scope = current_scope;
702 tree block, context, p;
705 bool functionbody = scope->function_body;
706 bool keep = functionbody || scope->keep || scope->bindings;
708 c_end_vm_scope (scope->depth);
710 /* If appropriate, create a BLOCK to record the decls for the life
715 block = make_node (BLOCK);
716 BLOCK_SUBBLOCKS (block) = scope->blocks;
717 TREE_USED (block) = 1;
719 /* In each subblock, record that this is its superior. */
720 for (p = scope->blocks; p; p = TREE_CHAIN (p))
721 BLOCK_SUPERCONTEXT (p) = block;
723 BLOCK_VARS (block) = 0;
726 /* The TYPE_CONTEXTs for all of the tagged types belonging to this
727 scope must be set so that they point to the appropriate
728 construct, i.e. either to the current FUNCTION_DECL node, or
729 else to the BLOCK node we just constructed.
731 Note that for tagged types whose scope is just the formal
732 parameter list for some function type specification, we can't
733 properly set their TYPE_CONTEXTs here, because we don't have a
734 pointer to the appropriate FUNCTION_TYPE node readily available
735 to us. For those cases, the TYPE_CONTEXTs of the relevant tagged
736 type nodes get set in `grokdeclarator' as soon as we have created
737 the FUNCTION_TYPE node which will represent the "scope" for these
738 "parameter list local" tagged types. */
739 if (scope->function_body)
740 context = current_function_decl;
741 else if (scope == file_scope)
743 tree file_decl = build_decl (TRANSLATION_UNIT_DECL, 0, 0);
744 TREE_CHAIN (file_decl) = all_translation_units;
745 all_translation_units = file_decl;
751 /* Clear all bindings in this scope. */
752 for (b = scope->bindings; b; b = free_binding_and_advance (b))
755 switch (TREE_CODE (p))
758 /* Warnings for unused labels, errors for undefined labels. */
759 if (TREE_USED (p) && !DECL_INITIAL (p))
761 error ("label %q+D used but not defined", p);
762 DECL_INITIAL (p) = error_mark_node;
764 else if (!TREE_USED (p) && warn_unused_label)
766 if (DECL_INITIAL (p))
767 warning (0, "label %q+D defined but not used", p);
769 warning (0, "label %q+D declared but not defined", p);
771 /* Labels go in BLOCK_VARS. */
772 TREE_CHAIN (p) = BLOCK_VARS (block);
773 BLOCK_VARS (block) = p;
774 gcc_assert (I_LABEL_BINDING (b->id) == b);
775 I_LABEL_BINDING (b->id) = b->shadowed;
781 set_type_context (p, context);
783 /* Types may not have tag-names, in which case the type
784 appears in the bindings list with b->id NULL. */
787 gcc_assert (I_TAG_BINDING (b->id) == b);
788 I_TAG_BINDING (b->id) = b->shadowed;
793 /* Propagate TREE_ADDRESSABLE from nested functions to their
794 containing functions. */
795 if (!TREE_ASM_WRITTEN (p)
796 && DECL_INITIAL (p) != 0
797 && TREE_ADDRESSABLE (p)
798 && DECL_ABSTRACT_ORIGIN (p) != 0
799 && DECL_ABSTRACT_ORIGIN (p) != p)
800 TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (p)) = 1;
801 if (!DECL_EXTERNAL (p)
803 && scope != file_scope
804 && scope != external_scope)
806 error ("nested function %q+D declared but never defined", p);
807 undef_nested_function = true;
809 /* C99 6.7.4p6: "a function with external linkage... declared
810 with an inline function specifier ... shall also be defined in the
811 same translation unit." */
812 else if (DECL_DECLARED_INLINE_P (p)
816 pedwarn ("inline function %q+D declared but never defined", p);
821 /* Warnings for unused variables. */
823 && !TREE_NO_WARNING (p)
824 && !DECL_IN_SYSTEM_HEADER (p)
826 && !DECL_ARTIFICIAL (p)
827 && scope != file_scope
828 && scope != external_scope)
829 warning (OPT_Wunused_variable, "unused variable %q+D", p);
833 error ("type of array %q+D completed incompatibly with"
834 " implicit initialization", p);
841 /* All of these go in BLOCK_VARS, but only if this is the
842 binding in the home scope. */
845 TREE_CHAIN (p) = BLOCK_VARS (block);
846 BLOCK_VARS (block) = p;
848 /* If this is the file scope, and we are processing more
849 than one translation unit in this compilation, set
850 DECL_CONTEXT of each decl to the TRANSLATION_UNIT_DECL.
851 This makes same_translation_unit_p work, and causes
852 static declarations to be given disambiguating suffixes. */
853 if (scope == file_scope && num_in_fnames > 1)
855 DECL_CONTEXT (p) = context;
856 if (TREE_CODE (p) == TYPE_DECL)
857 set_type_context (TREE_TYPE (p), context);
861 /* Parameters go in DECL_ARGUMENTS, not BLOCK_VARS, and have
862 already been put there by store_parm_decls. Unused-
863 parameter warnings are handled by function.c.
864 error_mark_node obviously does not go in BLOCK_VARS and
865 does not get unused-variable warnings. */
868 /* It is possible for a decl not to have a name. We get
869 here with b->id NULL in this case. */
872 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
873 I_SYMBOL_BINDING (b->id) = b->shadowed;
874 if (b->shadowed && b->shadowed->type)
875 TREE_TYPE (b->shadowed->decl) = b->shadowed->type;
885 /* Dispose of the block that we just made inside some higher level. */
886 if ((scope->function_body || scope == file_scope) && context)
888 DECL_INITIAL (context) = block;
889 BLOCK_SUPERCONTEXT (block) = context;
891 else if (scope->outer)
894 SCOPE_LIST_APPEND (scope->outer, blocks, block);
895 /* If we did not make a block for the scope just exited, any
896 blocks made for inner scopes must be carried forward so they
897 will later become subblocks of something else. */
898 else if (scope->blocks)
899 SCOPE_LIST_CONCAT (scope->outer, blocks, scope, blocks);
902 /* Pop the current scope, and free the structure for reuse. */
903 current_scope = scope->outer;
904 if (scope->function_body)
905 current_function_scope = scope->outer_function;
907 memset (scope, 0, sizeof (struct c_scope));
908 scope->outer = scope_freelist;
909 scope_freelist = scope;
915 push_file_scope (void)
923 file_scope = current_scope;
925 start_fname_decls ();
927 for (decl = visible_builtins; decl; decl = TREE_CHAIN (decl))
928 bind (DECL_NAME (decl), decl, file_scope,
929 /*invisible=*/false, /*nested=*/true);
933 pop_file_scope (void)
935 /* In case there were missing closebraces, get us back to the global
937 while (current_scope != file_scope)
940 /* __FUNCTION__ is defined at file scope (""). This
941 call may not be necessary as my tests indicate it
942 still works without it. */
943 finish_fname_decls ();
945 /* This is the point to write out a PCH if we're doing that.
946 In that case we do not want to do anything else. */
949 c_common_write_pch ();
953 /* Pop off the file scope and close this translation unit. */
957 maybe_apply_pending_pragma_weaks ();
958 cgraph_finalize_compilation_unit ();
961 /* Insert BLOCK at the end of the list of subblocks of the current
962 scope. This is used when a BIND_EXPR is expanded, to handle the
963 BLOCK node inside the BIND_EXPR. */
966 insert_block (tree block)
968 TREE_USED (block) = 1;
969 SCOPE_LIST_APPEND (current_scope, blocks, block);
972 /* Push a definition or a declaration of struct, union or enum tag "name".
973 "type" should be the type node.
974 We assume that the tag "name" is not already defined.
976 Note that the definition may really be just a forward reference.
977 In that case, the TYPE_SIZE will be zero. */
980 pushtag (tree name, tree type)
982 /* Record the identifier as the type's name if it has none. */
983 if (name && !TYPE_NAME (type))
984 TYPE_NAME (type) = name;
985 bind (name, type, current_scope, /*invisible=*/false, /*nested=*/false);
987 /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
988 tagged type we just added to the current scope. This fake
989 NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
990 to output a representation of a tagged type, and it also gives
991 us a convenient place to record the "scope start" address for the
994 TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));
996 /* An approximation for now, so we can tell this is a function-scope tag.
997 This will be updated in pop_scope. */
998 TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
1001 /* Subroutine of compare_decls. Allow harmless mismatches in return
1002 and argument types provided that the type modes match. This function
1003 return a unified type given a suitable match, and 0 otherwise. */
1006 match_builtin_function_types (tree newtype, tree oldtype)
1008 tree newrettype, oldrettype;
1009 tree newargs, oldargs;
1010 tree trytype, tryargs;
1012 /* Accept the return type of the new declaration if same modes. */
1013 oldrettype = TREE_TYPE (oldtype);
1014 newrettype = TREE_TYPE (newtype);
1016 if (TYPE_MODE (oldrettype) != TYPE_MODE (newrettype))
1019 oldargs = TYPE_ARG_TYPES (oldtype);
1020 newargs = TYPE_ARG_TYPES (newtype);
1023 while (oldargs || newargs)
1027 || !TREE_VALUE (oldargs)
1028 || !TREE_VALUE (newargs)
1029 || TYPE_MODE (TREE_VALUE (oldargs))
1030 != TYPE_MODE (TREE_VALUE (newargs)))
1033 oldargs = TREE_CHAIN (oldargs);
1034 newargs = TREE_CHAIN (newargs);
1037 trytype = build_function_type (newrettype, tryargs);
1038 return build_type_attribute_variant (trytype, TYPE_ATTRIBUTES (oldtype));
1041 /* Subroutine of diagnose_mismatched_decls. Check for function type
1042 mismatch involving an empty arglist vs a nonempty one and give clearer
1045 diagnose_arglist_conflict (tree newdecl, tree olddecl,
1046 tree newtype, tree oldtype)
1050 if (TREE_CODE (olddecl) != FUNCTION_DECL
1051 || !comptypes (TREE_TYPE (oldtype), TREE_TYPE (newtype))
1052 || !((TYPE_ARG_TYPES (oldtype) == 0 && DECL_INITIAL (olddecl) == 0)
1054 (TYPE_ARG_TYPES (newtype) == 0 && DECL_INITIAL (newdecl) == 0)))
1057 t = TYPE_ARG_TYPES (oldtype);
1059 t = TYPE_ARG_TYPES (newtype);
1060 for (; t; t = TREE_CHAIN (t))
1062 tree type = TREE_VALUE (t);
1064 if (TREE_CHAIN (t) == 0
1065 && TYPE_MAIN_VARIANT (type) != void_type_node)
1067 inform ("a parameter list with an ellipsis can%'t match "
1068 "an empty parameter name list declaration");
1072 if (c_type_promotes_to (type) != type)
1074 inform ("an argument type that has a default promotion can%'t match "
1075 "an empty parameter name list declaration");
1081 /* Another subroutine of diagnose_mismatched_decls. OLDDECL is an
1082 old-style function definition, NEWDECL is a prototype declaration.
1083 Diagnose inconsistencies in the argument list. Returns TRUE if
1084 the prototype is compatible, FALSE if not. */
1086 validate_proto_after_old_defn (tree newdecl, tree newtype, tree oldtype)
1088 tree newargs, oldargs;
1091 #define END_OF_ARGLIST(t) ((t) == void_type_node)
1093 oldargs = TYPE_ACTUAL_ARG_TYPES (oldtype);
1094 newargs = TYPE_ARG_TYPES (newtype);
1099 tree oldargtype = TREE_VALUE (oldargs);
1100 tree newargtype = TREE_VALUE (newargs);
1102 if (oldargtype == error_mark_node || newargtype == error_mark_node)
1105 oldargtype = TYPE_MAIN_VARIANT (oldargtype);
1106 newargtype = TYPE_MAIN_VARIANT (newargtype);
1108 if (END_OF_ARGLIST (oldargtype) && END_OF_ARGLIST (newargtype))
1111 /* Reaching the end of just one list means the two decls don't
1112 agree on the number of arguments. */
1113 if (END_OF_ARGLIST (oldargtype))
1115 error ("prototype for %q+D declares more arguments "
1116 "than previous old-style definition", newdecl);
1119 else if (END_OF_ARGLIST (newargtype))
1121 error ("prototype for %q+D declares fewer arguments "
1122 "than previous old-style definition", newdecl);
1126 /* Type for passing arg must be consistent with that declared
1128 else if (!comptypes (oldargtype, newargtype))
1130 error ("prototype for %q+D declares argument %d"
1131 " with incompatible type",
1136 oldargs = TREE_CHAIN (oldargs);
1137 newargs = TREE_CHAIN (newargs);
1141 /* If we get here, no errors were found, but do issue a warning
1142 for this poor-style construct. */
1143 warning (0, "prototype for %q+D follows non-prototype definition",
1146 #undef END_OF_ARGLIST
1149 /* Subroutine of diagnose_mismatched_decls. Report the location of DECL,
1150 first in a pair of mismatched declarations, using the diagnostic
1153 locate_old_decl (tree decl, void (*diag)(const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2))
1155 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1157 else if (DECL_INITIAL (decl))
1158 diag (G_("previous definition of %q+D was here"), decl);
1159 else if (C_DECL_IMPLICIT (decl))
1160 diag (G_("previous implicit declaration of %q+D was here"), decl);
1162 diag (G_("previous declaration of %q+D was here"), decl);
1165 /* Subroutine of duplicate_decls. Compare NEWDECL to OLDDECL.
1166 Returns true if the caller should proceed to merge the two, false
1167 if OLDDECL should simply be discarded. As a side effect, issues
1168 all necessary diagnostics for invalid or poor-style combinations.
1169 If it returns true, writes the types of NEWDECL and OLDDECL to
1170 *NEWTYPEP and *OLDTYPEP - these may have been adjusted from
1171 TREE_TYPE (NEWDECL, OLDDECL) respectively. */
1174 diagnose_mismatched_decls (tree newdecl, tree olddecl,
1175 tree *newtypep, tree *oldtypep)
1177 tree newtype, oldtype;
1178 bool pedwarned = false;
1179 bool warned = false;
1182 #define DECL_EXTERN_INLINE(DECL) (DECL_DECLARED_INLINE_P (DECL) \
1183 && DECL_EXTERNAL (DECL))
1185 /* If we have error_mark_node for either decl or type, just discard
1186 the previous decl - we're in an error cascade already. */
1187 if (olddecl == error_mark_node || newdecl == error_mark_node)
1189 *oldtypep = oldtype = TREE_TYPE (olddecl);
1190 *newtypep = newtype = TREE_TYPE (newdecl);
1191 if (oldtype == error_mark_node || newtype == error_mark_node)
1194 /* Two different categories of symbol altogether. This is an error
1195 unless OLDDECL is a builtin. OLDDECL will be discarded in any case. */
1196 if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1198 if (!(TREE_CODE (olddecl) == FUNCTION_DECL
1199 && DECL_BUILT_IN (olddecl)
1200 && !C_DECL_DECLARED_BUILTIN (olddecl)))
1202 error ("%q+D redeclared as different kind of symbol", newdecl);
1203 locate_old_decl (olddecl, error);
1205 else if (TREE_PUBLIC (newdecl))
1206 warning (0, "built-in function %q+D declared as non-function",
1209 warning (OPT_Wshadow, "declaration of %q+D shadows "
1210 "a built-in function", newdecl);
1214 /* Enumerators have no linkage, so may only be declared once in a
1216 if (TREE_CODE (olddecl) == CONST_DECL)
1218 error ("redeclaration of enumerator %q+D", newdecl);
1219 locate_old_decl (olddecl, error);
1223 if (!comptypes (oldtype, newtype))
1225 if (TREE_CODE (olddecl) == FUNCTION_DECL
1226 && DECL_BUILT_IN (olddecl) && !C_DECL_DECLARED_BUILTIN (olddecl))
1228 /* Accept harmless mismatch in function types.
1229 This is for the ffs and fprintf builtins. */
1230 tree trytype = match_builtin_function_types (newtype, oldtype);
1232 if (trytype && comptypes (newtype, trytype))
1233 *oldtypep = oldtype = trytype;
1236 /* If types don't match for a built-in, throw away the
1237 built-in. No point in calling locate_old_decl here, it
1238 won't print anything. */
1239 warning (0, "conflicting types for built-in function %q+D",
1244 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1245 && DECL_IS_BUILTIN (olddecl))
1247 /* A conflicting function declaration for a predeclared
1248 function that isn't actually built in. Objective C uses
1249 these. The new declaration silently overrides everything
1250 but the volatility (i.e. noreturn) indication. See also
1251 below. FIXME: Make Objective C use normal builtins. */
1252 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1255 /* Permit void foo (...) to match int foo (...) if the latter is
1256 the definition and implicit int was used. See
1257 c-torture/compile/920625-2.c. */
1258 else if (TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl)
1259 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == void_type_node
1260 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == integer_type_node
1261 && C_FUNCTION_IMPLICIT_INT (newdecl) && !DECL_INITIAL (olddecl))
1263 pedwarn ("conflicting types for %q+D", newdecl);
1264 /* Make sure we keep void as the return type. */
1265 TREE_TYPE (newdecl) = *newtypep = newtype = oldtype;
1266 C_FUNCTION_IMPLICIT_INT (newdecl) = 0;
1269 /* Permit void foo (...) to match an earlier call to foo (...) with
1270 no declared type (thus, implicitly int). */
1271 else if (TREE_CODE (newdecl) == FUNCTION_DECL
1272 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == void_type_node
1273 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == integer_type_node
1274 && C_DECL_IMPLICIT (olddecl) && !DECL_INITIAL (olddecl))
1276 pedwarn ("conflicting types for %q+D", newdecl);
1277 /* Make sure we keep void as the return type. */
1278 TREE_TYPE (olddecl) = *oldtypep = oldtype = newtype;
1283 if (TYPE_QUALS (newtype) != TYPE_QUALS (oldtype))
1284 error ("conflicting type qualifiers for %q+D", newdecl);
1286 error ("conflicting types for %q+D", newdecl);
1287 diagnose_arglist_conflict (newdecl, olddecl, newtype, oldtype);
1288 locate_old_decl (olddecl, error);
1293 /* Redeclaration of a type is a constraint violation (6.7.2.3p1),
1294 but silently ignore the redeclaration if either is in a system
1295 header. (Conflicting redeclarations were handled above.) */
1296 if (TREE_CODE (newdecl) == TYPE_DECL)
1298 if (DECL_IN_SYSTEM_HEADER (newdecl) || DECL_IN_SYSTEM_HEADER (olddecl))
1299 return true; /* Allow OLDDECL to continue in use. */
1301 error ("redefinition of typedef %q+D", newdecl);
1302 locate_old_decl (olddecl, error);
1306 /* Function declarations can either be 'static' or 'extern' (no
1307 qualifier is equivalent to 'extern' - C99 6.2.2p5) and therefore
1308 can never conflict with each other on account of linkage
1309 (6.2.2p4). Multiple definitions are not allowed (6.9p3,5) but
1310 gnu89 mode permits two definitions if one is 'extern inline' and
1311 one is not. The non- extern-inline definition supersedes the
1312 extern-inline definition. */
1314 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
1316 /* If you declare a built-in function name as static, or
1317 define the built-in with an old-style definition (so we
1318 can't validate the argument list) the built-in definition is
1319 overridden, but optionally warn this was a bad choice of name. */
1320 if (DECL_BUILT_IN (olddecl)
1321 && !C_DECL_DECLARED_BUILTIN (olddecl)
1322 && (!TREE_PUBLIC (newdecl)
1323 || (DECL_INITIAL (newdecl)
1324 && !TYPE_ARG_TYPES (TREE_TYPE (newdecl)))))
1326 warning (OPT_Wshadow, "declaration of %q+D shadows "
1327 "a built-in function", newdecl);
1328 /* Discard the old built-in function. */
1332 if (DECL_INITIAL (newdecl))
1334 if (DECL_INITIAL (olddecl))
1336 /* If both decls are in the same TU and the new declaration
1337 isn't overriding an extern inline reject the new decl.
1338 In c99, no overriding is allowed in the same translation
1340 if ((!DECL_EXTERN_INLINE (olddecl)
1341 || DECL_EXTERN_INLINE (newdecl)
1342 #if WANT_C99_INLINE_SEMANTICS
1344 && (!DECL_DECLARED_INLINE_P (olddecl)
1345 || !lookup_attribute ("gnu_inline",
1346 DECL_ATTRIBUTES (olddecl)))
1347 && (!DECL_DECLARED_INLINE_P (newdecl)
1348 || !lookup_attribute ("gnu_inline",
1349 DECL_ATTRIBUTES (newdecl))))
1350 #endif /* WANT_C99_INLINE_SEMANTICS */
1352 && same_translation_unit_p (newdecl, olddecl))
1354 error ("redefinition of %q+D", newdecl);
1355 locate_old_decl (olddecl, error);
1360 /* If we have a prototype after an old-style function definition,
1361 the argument types must be checked specially. */
1362 else if (DECL_INITIAL (olddecl)
1363 && !TYPE_ARG_TYPES (oldtype) && TYPE_ARG_TYPES (newtype)
1364 && TYPE_ACTUAL_ARG_TYPES (oldtype)
1365 && !validate_proto_after_old_defn (newdecl, newtype, oldtype))
1367 locate_old_decl (olddecl, error);
1370 /* A non-static declaration (even an "extern") followed by a
1371 static declaration is undefined behavior per C99 6.2.2p3-5,7.
1372 The same is true for a static forward declaration at block
1373 scope followed by a non-static declaration/definition at file
1374 scope. Static followed by non-static at the same scope is
1375 not undefined behavior, and is the most convenient way to get
1376 some effects (see e.g. what unwind-dw2-fde-glibc.c does to
1377 the definition of _Unwind_Find_FDE in unwind-dw2-fde.c), but
1378 we do diagnose it if -Wtraditional. */
1379 if (TREE_PUBLIC (olddecl) && !TREE_PUBLIC (newdecl))
1381 /* Two exceptions to the rule. If olddecl is an extern
1382 inline, or a predeclared function that isn't actually
1383 built in, newdecl silently overrides olddecl. The latter
1384 occur only in Objective C; see also above. (FIXME: Make
1385 Objective C use normal builtins.) */
1386 if (!DECL_IS_BUILTIN (olddecl)
1387 && !DECL_EXTERN_INLINE (olddecl))
1389 error ("static declaration of %q+D follows "
1390 "non-static declaration", newdecl);
1391 locate_old_decl (olddecl, error);
1395 else if (TREE_PUBLIC (newdecl) && !TREE_PUBLIC (olddecl))
1397 if (DECL_CONTEXT (olddecl))
1399 error ("non-static declaration of %q+D follows "
1400 "static declaration", newdecl);
1401 locate_old_decl (olddecl, error);
1404 else if (warn_traditional)
1406 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1407 "follows static declaration", newdecl);
1412 /* Make sure gnu_inline attribute is either not present, or
1413 present on all inline decls. */
1414 if (DECL_DECLARED_INLINE_P (olddecl)
1415 && DECL_DECLARED_INLINE_P (newdecl))
1417 bool newa = lookup_attribute ("gnu_inline",
1418 DECL_ATTRIBUTES (newdecl)) != NULL;
1419 bool olda = lookup_attribute ("gnu_inline",
1420 DECL_ATTRIBUTES (olddecl)) != NULL;
1423 error ("%<gnu_inline%> attribute present on %q+D",
1424 newa ? newdecl : olddecl);
1425 error ("%Jbut not here", newa ? olddecl : newdecl);
1429 else if (TREE_CODE (newdecl) == VAR_DECL)
1431 /* Only variables can be thread-local, and all declarations must
1432 agree on this property. */
1433 if (C_DECL_THREADPRIVATE_P (olddecl) && !DECL_THREAD_LOCAL_P (newdecl))
1435 /* Nothing to check. Since OLDDECL is marked threadprivate
1436 and NEWDECL does not have a thread-local attribute, we
1437 will merge the threadprivate attribute into NEWDECL. */
1440 else if (DECL_THREAD_LOCAL_P (newdecl) != DECL_THREAD_LOCAL_P (olddecl))
1442 if (DECL_THREAD_LOCAL_P (newdecl))
1443 error ("thread-local declaration of %q+D follows "
1444 "non-thread-local declaration", newdecl);
1446 error ("non-thread-local declaration of %q+D follows "
1447 "thread-local declaration", newdecl);
1449 locate_old_decl (olddecl, error);
1453 /* Multiple initialized definitions are not allowed (6.9p3,5). */
1454 if (DECL_INITIAL (newdecl) && DECL_INITIAL (olddecl))
1456 error ("redefinition of %q+D", newdecl);
1457 locate_old_decl (olddecl, error);
1461 /* Objects declared at file scope: if the first declaration had
1462 external linkage (even if it was an external reference) the
1463 second must have external linkage as well, or the behavior is
1464 undefined. If the first declaration had internal linkage, then
1465 the second must too, or else be an external reference (in which
1466 case the composite declaration still has internal linkage).
1467 As for function declarations, we warn about the static-then-
1468 extern case only for -Wtraditional. See generally 6.2.2p3-5,7. */
1469 if (DECL_FILE_SCOPE_P (newdecl)
1470 && TREE_PUBLIC (newdecl) != TREE_PUBLIC (olddecl))
1472 if (DECL_EXTERNAL (newdecl))
1474 if (!DECL_FILE_SCOPE_P (olddecl))
1476 error ("extern declaration of %q+D follows "
1477 "declaration with no linkage", newdecl);
1478 locate_old_decl (olddecl, error);
1481 else if (warn_traditional)
1483 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1484 "follows static declaration", newdecl);
1490 if (TREE_PUBLIC (newdecl))
1491 error ("non-static declaration of %q+D follows "
1492 "static declaration", newdecl);
1494 error ("static declaration of %q+D follows "
1495 "non-static declaration", newdecl);
1497 locate_old_decl (olddecl, error);
1501 /* Two objects with the same name declared at the same block
1502 scope must both be external references (6.7p3). */
1503 else if (!DECL_FILE_SCOPE_P (newdecl))
1505 if (DECL_EXTERNAL (newdecl))
1507 /* Extern with initializer at block scope, which will
1508 already have received an error. */
1510 else if (DECL_EXTERNAL (olddecl))
1512 error ("declaration of %q+D with no linkage follows "
1513 "extern declaration", newdecl);
1514 locate_old_decl (olddecl, error);
1518 error ("redeclaration of %q+D with no linkage", newdecl);
1519 locate_old_decl (olddecl, error);
1527 /* All decls must agree on a visibility. */
1528 if (CODE_CONTAINS_STRUCT (TREE_CODE (newdecl), TS_DECL_WITH_VIS)
1529 && DECL_VISIBILITY_SPECIFIED (newdecl) && DECL_VISIBILITY_SPECIFIED (olddecl)
1530 && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
1532 warning (0, "redeclaration of %q+D with different visibility "
1533 "(old visibility preserved)", newdecl);
1537 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1539 /* Diagnose inline __attribute__ ((noinline)) which is silly. */
1540 if (DECL_DECLARED_INLINE_P (newdecl)
1541 && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1543 warning (OPT_Wattributes, "inline declaration of %qD follows "
1544 "declaration with attribute noinline", newdecl);
1547 else if (DECL_DECLARED_INLINE_P (olddecl)
1548 && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1550 warning (OPT_Wattributes, "declaration of %q+D with attribute "
1551 "noinline follows inline declaration ", newdecl);
1555 /* Inline declaration after use or definition.
1556 ??? Should we still warn about this now we have unit-at-a-time
1557 mode and can get it right?
1558 Definitely don't complain if the decls are in different translation
1560 C99 permits this, so don't warn in that case. (The function
1561 may not be inlined everywhere in function-at-a-time mode, but
1562 we still shouldn't warn.) */
1563 if (DECL_DECLARED_INLINE_P (newdecl) && !DECL_DECLARED_INLINE_P (olddecl)
1564 && same_translation_unit_p (olddecl, newdecl)
1567 if (TREE_USED (olddecl))
1569 warning (0, "%q+D declared inline after being called", olddecl);
1572 else if (DECL_INITIAL (olddecl))
1574 warning (0, "%q+D declared inline after its definition", olddecl);
1579 else /* PARM_DECL, VAR_DECL */
1581 /* Redeclaration of a parameter is a constraint violation (this is
1582 not explicitly stated, but follows from C99 6.7p3 [no more than
1583 one declaration of the same identifier with no linkage in the
1584 same scope, except type tags] and 6.2.2p6 [parameters have no
1585 linkage]). We must check for a forward parameter declaration,
1586 indicated by TREE_ASM_WRITTEN on the old declaration - this is
1587 an extension, the mandatory diagnostic for which is handled by
1588 mark_forward_parm_decls. */
1590 if (TREE_CODE (newdecl) == PARM_DECL
1591 && (!TREE_ASM_WRITTEN (olddecl) || TREE_ASM_WRITTEN (newdecl)))
1593 error ("redefinition of parameter %q+D", newdecl);
1594 locate_old_decl (olddecl, error);
1599 /* Optional warning for completely redundant decls. */
1600 if (!warned && !pedwarned
1601 && warn_redundant_decls
1602 /* Don't warn about a function declaration followed by a
1604 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1605 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl))
1606 /* Don't warn about redundant redeclarations of builtins. */
1607 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1608 && !DECL_BUILT_IN (newdecl)
1609 && DECL_BUILT_IN (olddecl)
1610 && !C_DECL_DECLARED_BUILTIN (olddecl))
1611 /* Don't warn about an extern followed by a definition. */
1612 && !(DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl))
1613 /* Don't warn about forward parameter decls. */
1614 && !(TREE_CODE (newdecl) == PARM_DECL
1615 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
1616 /* Don't warn about a variable definition following a declaration. */
1617 && !(TREE_CODE (newdecl) == VAR_DECL
1618 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl)))
1620 warning (OPT_Wredundant_decls, "redundant redeclaration of %q+D",
1625 /* Report location of previous decl/defn in a consistent manner. */
1626 if (warned || pedwarned)
1627 locate_old_decl (olddecl, pedwarned ? pedwarn : warning0);
1629 #undef DECL_EXTERN_INLINE
1634 /* Subroutine of duplicate_decls. NEWDECL has been found to be
1635 consistent with OLDDECL, but carries new information. Merge the
1636 new information into OLDDECL. This function issues no
1640 merge_decls (tree newdecl, tree olddecl, tree newtype, tree oldtype)
1642 bool new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
1643 && DECL_INITIAL (newdecl) != 0);
1644 bool new_is_prototype = (TREE_CODE (newdecl) == FUNCTION_DECL
1645 && TYPE_ARG_TYPES (TREE_TYPE (newdecl)) != 0);
1646 bool old_is_prototype = (TREE_CODE (olddecl) == FUNCTION_DECL
1647 && TYPE_ARG_TYPES (TREE_TYPE (olddecl)) != 0);
1648 bool extern_changed = false;
1650 /* For real parm decl following a forward decl, rechain the old decl
1651 in its new location and clear TREE_ASM_WRITTEN (it's not a
1652 forward decl anymore). */
1653 if (TREE_CODE (newdecl) == PARM_DECL
1654 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
1656 struct c_binding *b, **here;
1658 for (here = ¤t_scope->bindings; *here; here = &(*here)->prev)
1659 if ((*here)->decl == olddecl)
1666 b->prev = current_scope->bindings;
1667 current_scope->bindings = b;
1669 TREE_ASM_WRITTEN (olddecl) = 0;
1672 DECL_ATTRIBUTES (newdecl)
1673 = targetm.merge_decl_attributes (olddecl, newdecl);
1675 /* Merge the data types specified in the two decls. */
1677 = TREE_TYPE (olddecl)
1678 = composite_type (newtype, oldtype);
1680 /* Lay the type out, unless already done. */
1681 if (!comptypes (oldtype, TREE_TYPE (newdecl)))
1683 if (TREE_TYPE (newdecl) != error_mark_node)
1684 layout_type (TREE_TYPE (newdecl));
1685 if (TREE_CODE (newdecl) != FUNCTION_DECL
1686 && TREE_CODE (newdecl) != TYPE_DECL
1687 && TREE_CODE (newdecl) != CONST_DECL)
1688 layout_decl (newdecl, 0);
1692 /* Since the type is OLDDECL's, make OLDDECL's size go with. */
1693 DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
1694 DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
1695 DECL_MODE (newdecl) = DECL_MODE (olddecl);
1696 if (TREE_CODE (olddecl) != FUNCTION_DECL)
1697 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
1699 DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
1700 DECL_USER_ALIGN (newdecl) |= DECL_ALIGN (olddecl);
1705 /* Merge the type qualifiers. */
1706 if (TREE_READONLY (newdecl))
1707 TREE_READONLY (olddecl) = 1;
1709 if (TREE_THIS_VOLATILE (newdecl))
1711 TREE_THIS_VOLATILE (olddecl) = 1;
1712 if (TREE_CODE (newdecl) == VAR_DECL)
1713 make_var_volatile (newdecl);
1716 /* Merge deprecatedness. */
1717 if (TREE_DEPRECATED (newdecl))
1718 TREE_DEPRECATED (olddecl) = 1;
1720 /* Keep source location of definition rather than declaration and of
1721 prototype rather than non-prototype unless that prototype is
1723 if ((DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0)
1724 || (old_is_prototype && !new_is_prototype
1725 && !C_DECL_BUILTIN_PROTOTYPE (olddecl)))
1726 DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
1728 /* Merge the initialization information. */
1729 if (DECL_INITIAL (newdecl) == 0)
1730 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1732 /* Merge the threadprivate attribute. */
1733 if (TREE_CODE (olddecl) == VAR_DECL && C_DECL_THREADPRIVATE_P (olddecl))
1735 DECL_TLS_MODEL (newdecl) = DECL_TLS_MODEL (olddecl);
1736 C_DECL_THREADPRIVATE_P (newdecl) = 1;
1739 if (CODE_CONTAINS_STRUCT (TREE_CODE (olddecl), TS_DECL_WITH_VIS))
1741 /* Merge the unused-warning information. */
1742 if (DECL_IN_SYSTEM_HEADER (olddecl))
1743 DECL_IN_SYSTEM_HEADER (newdecl) = 1;
1744 else if (DECL_IN_SYSTEM_HEADER (newdecl))
1745 DECL_IN_SYSTEM_HEADER (olddecl) = 1;
1747 /* Merge the section attribute.
1748 We want to issue an error if the sections conflict but that
1749 must be done later in decl_attributes since we are called
1750 before attributes are assigned. */
1751 if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
1752 DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
1754 /* Copy the assembler name.
1755 Currently, it can only be defined in the prototype. */
1756 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
1758 /* Use visibility of whichever declaration had it specified */
1759 if (DECL_VISIBILITY_SPECIFIED (olddecl))
1761 DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
1762 DECL_VISIBILITY_SPECIFIED (newdecl) = 1;
1765 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1767 DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
1768 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1769 DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
1770 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
1771 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
1772 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1773 TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
1774 DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
1775 DECL_IS_PURE (newdecl) |= DECL_IS_PURE (olddecl);
1776 DECL_IS_NOVOPS (newdecl) |= DECL_IS_NOVOPS (olddecl);
1779 /* Merge the storage class information. */
1780 merge_weak (newdecl, olddecl);
1782 /* For functions, static overrides non-static. */
1783 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1785 TREE_PUBLIC (newdecl) &= TREE_PUBLIC (olddecl);
1786 /* This is since we don't automatically
1787 copy the attributes of NEWDECL into OLDDECL. */
1788 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1789 /* If this clears `static', clear it in the identifier too. */
1790 if (!TREE_PUBLIC (olddecl))
1791 TREE_PUBLIC (DECL_NAME (olddecl)) = 0;
1795 #if WANT_C99_INLINE_SEMANTICS
1796 /* In c99, 'extern' declaration before (or after) 'inline' means this
1797 function is not DECL_EXTERNAL, unless 'gnu_inline' attribute
1799 if (TREE_CODE (newdecl) == FUNCTION_DECL
1801 && (DECL_DECLARED_INLINE_P (newdecl)
1802 || DECL_DECLARED_INLINE_P (olddecl))
1803 && (!DECL_DECLARED_INLINE_P (newdecl)
1804 || !DECL_DECLARED_INLINE_P (olddecl)
1805 || !DECL_EXTERNAL (olddecl))
1806 && DECL_EXTERNAL (newdecl)
1807 && !lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (newdecl)))
1808 DECL_EXTERNAL (newdecl) = 0;
1809 #endif /* WANT_C99_INLINE_SEMANTICS */
1811 if (DECL_EXTERNAL (newdecl))
1813 TREE_STATIC (newdecl) = TREE_STATIC (olddecl);
1814 DECL_EXTERNAL (newdecl) = DECL_EXTERNAL (olddecl);
1816 /* An extern decl does not override previous storage class. */
1817 TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
1818 if (!DECL_EXTERNAL (newdecl))
1820 DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
1821 DECL_COMMON (newdecl) = DECL_COMMON (olddecl);
1826 TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
1827 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1830 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1832 /* If we're redefining a function previously defined as extern
1833 inline, make sure we emit debug info for the inline before we
1834 throw it away, in case it was inlined into a function that
1835 hasn't been written out yet. */
1836 if (new_is_definition && DECL_INITIAL (olddecl))
1838 if (TREE_USED (olddecl)
1839 /* In unit-at-a-time mode we never inline re-defined extern
1840 inline functions. */
1841 && !flag_unit_at_a_time
1842 && cgraph_function_possibly_inlined_p (olddecl))
1843 (*debug_hooks->outlining_inline_function) (olddecl);
1845 /* The new defn must not be inline. */
1846 DECL_INLINE (newdecl) = 0;
1847 DECL_UNINLINABLE (newdecl) = 1;
1851 /* If either decl says `inline', this fn is inline, unless
1852 its definition was passed already. */
1853 if (DECL_DECLARED_INLINE_P (newdecl)
1854 || DECL_DECLARED_INLINE_P (olddecl))
1855 DECL_DECLARED_INLINE_P (newdecl) = 1;
1857 DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
1858 = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
1861 if (DECL_BUILT_IN (olddecl))
1863 /* If redeclaring a builtin function, it stays built in.
1864 But it gets tagged as having been declared. */
1865 DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
1866 DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
1867 C_DECL_DECLARED_BUILTIN (newdecl) = 1;
1868 if (new_is_prototype)
1869 C_DECL_BUILTIN_PROTOTYPE (newdecl) = 0;
1871 C_DECL_BUILTIN_PROTOTYPE (newdecl)
1872 = C_DECL_BUILTIN_PROTOTYPE (olddecl);
1875 /* Also preserve various other info from the definition. */
1876 if (!new_is_definition)
1878 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
1879 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1880 DECL_STRUCT_FUNCTION (newdecl) = DECL_STRUCT_FUNCTION (olddecl);
1881 DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
1882 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
1884 /* Set DECL_INLINE on the declaration if we've got a body
1885 from which to instantiate. */
1886 if (DECL_INLINE (olddecl) && !DECL_UNINLINABLE (newdecl))
1888 DECL_INLINE (newdecl) = 1;
1889 DECL_ABSTRACT_ORIGIN (newdecl)
1890 = DECL_ABSTRACT_ORIGIN (olddecl);
1895 /* If a previous declaration said inline, mark the
1896 definition as inlinable. */
1897 if (DECL_DECLARED_INLINE_P (newdecl)
1898 && !DECL_UNINLINABLE (newdecl))
1899 DECL_INLINE (newdecl) = 1;
1903 extern_changed = DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl);
1905 /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
1906 But preserve OLDDECL's DECL_UID and DECL_CONTEXT. */
1908 unsigned olddecl_uid = DECL_UID (olddecl);
1909 tree olddecl_context = DECL_CONTEXT (olddecl);
1911 memcpy ((char *) olddecl + sizeof (struct tree_common),
1912 (char *) newdecl + sizeof (struct tree_common),
1913 sizeof (struct tree_decl_common) - sizeof (struct tree_common));
1914 switch (TREE_CODE (olddecl))
1924 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1925 (char *) newdecl + sizeof (struct tree_decl_common),
1926 tree_code_size (TREE_CODE (olddecl)) - sizeof (struct tree_decl_common));
1931 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1932 (char *) newdecl + sizeof (struct tree_decl_common),
1933 sizeof (struct tree_decl_non_common) - sizeof (struct tree_decl_common));
1935 DECL_UID (olddecl) = olddecl_uid;
1936 DECL_CONTEXT (olddecl) = olddecl_context;
1939 /* If OLDDECL had its DECL_RTL instantiated, re-invoke make_decl_rtl
1940 so that encode_section_info has a chance to look at the new decl
1941 flags and attributes. */
1942 if (DECL_RTL_SET_P (olddecl)
1943 && (TREE_CODE (olddecl) == FUNCTION_DECL
1944 || (TREE_CODE (olddecl) == VAR_DECL
1945 && TREE_STATIC (olddecl))))
1946 make_decl_rtl (olddecl);
1948 /* If we changed a function from DECL_EXTERNAL to !DECL_EXTERNAL,
1949 and the definition is coming from the old version, cgraph needs
1950 to be called again. */
1951 if (extern_changed && !new_is_definition
1952 && TREE_CODE (olddecl) == FUNCTION_DECL && DECL_INITIAL (olddecl))
1953 cgraph_finalize_function (olddecl, false);
1956 /* Handle when a new declaration NEWDECL has the same name as an old
1957 one OLDDECL in the same binding contour. Prints an error message
1960 If safely possible, alter OLDDECL to look like NEWDECL, and return
1961 true. Otherwise, return false. */
1964 duplicate_decls (tree newdecl, tree olddecl)
1966 tree newtype = NULL, oldtype = NULL;
1968 if (!diagnose_mismatched_decls (newdecl, olddecl, &newtype, &oldtype))
1970 /* Avoid `unused variable' and other warnings warnings for OLDDECL. */
1971 TREE_NO_WARNING (olddecl) = 1;
1975 merge_decls (newdecl, olddecl, newtype, oldtype);
1980 /* Check whether decl-node NEW_DECL shadows an existing declaration. */
1982 warn_if_shadowing (tree new_decl)
1984 struct c_binding *b;
1986 /* Shadow warnings wanted? */
1988 /* No shadow warnings for internally generated vars. */
1989 || DECL_IS_BUILTIN (new_decl)
1990 /* No shadow warnings for vars made for inlining. */
1991 || DECL_FROM_INLINE (new_decl))
1994 /* Is anything being shadowed? Invisible decls do not count. */
1995 for (b = I_SYMBOL_BINDING (DECL_NAME (new_decl)); b; b = b->shadowed)
1996 if (b->decl && b->decl != new_decl && !b->invisible)
1998 tree old_decl = b->decl;
2000 if (old_decl == error_mark_node)
2002 warning (OPT_Wshadow, "declaration of %q+D shadows previous "
2003 "non-variable", new_decl);
2006 else if (TREE_CODE (old_decl) == PARM_DECL)
2007 warning (OPT_Wshadow, "declaration of %q+D shadows a parameter",
2009 else if (DECL_FILE_SCOPE_P (old_decl))
2010 warning (OPT_Wshadow, "declaration of %q+D shadows a global "
2011 "declaration", new_decl);
2012 else if (TREE_CODE (old_decl) == FUNCTION_DECL
2013 && DECL_BUILT_IN (old_decl))
2015 warning (OPT_Wshadow, "declaration of %q+D shadows "
2016 "a built-in function", new_decl);
2020 warning (OPT_Wshadow, "declaration of %q+D shadows a previous local",
2023 warning (OPT_Wshadow, "%Jshadowed declaration is here", old_decl);
2030 /* Subroutine of pushdecl.
2032 X is a TYPE_DECL for a typedef statement. Create a brand new
2033 ..._TYPE node (which will be just a variant of the existing
2034 ..._TYPE node with identical properties) and then install X
2035 as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
2037 The whole point here is to end up with a situation where each
2038 and every ..._TYPE node the compiler creates will be uniquely
2039 associated with AT MOST one node representing a typedef name.
2040 This way, even though the compiler substitutes corresponding
2041 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
2042 early on, later parts of the compiler can always do the reverse
2043 translation and get back the corresponding typedef name. For
2046 typedef struct S MY_TYPE;
2049 Later parts of the compiler might only know that `object' was of
2050 type `struct S' if it were not for code just below. With this
2051 code however, later parts of the compiler see something like:
2053 struct S' == struct S
2054 typedef struct S' MY_TYPE;
2057 And they can then deduce (from the node for type struct S') that
2058 the original object declaration was:
2062 Being able to do this is important for proper support of protoize,
2063 and also for generating precise symbolic debugging information
2064 which takes full account of the programmer's (typedef) vocabulary.
2066 Obviously, we don't want to generate a duplicate ..._TYPE node if
2067 the TYPE_DECL node that we are now processing really represents a
2068 standard built-in type.
2070 Since all standard types are effectively declared at line zero
2071 in the source file, we can easily check to see if we are working
2072 on a standard type by checking the current value of lineno. */
2075 clone_underlying_type (tree x)
2077 if (DECL_IS_BUILTIN (x))
2079 if (TYPE_NAME (TREE_TYPE (x)) == 0)
2080 TYPE_NAME (TREE_TYPE (x)) = x;
2082 else if (TREE_TYPE (x) != error_mark_node
2083 && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
2085 tree tt = TREE_TYPE (x);
2086 DECL_ORIGINAL_TYPE (x) = tt;
2087 tt = build_variant_type_copy (tt);
2089 TREE_USED (tt) = TREE_USED (x);
2094 /* Record a decl-node X as belonging to the current lexical scope.
2095 Check for errors (such as an incompatible declaration for the same
2096 name already seen in the same scope).
2098 Returns either X or an old decl for the same name.
2099 If an old decl is returned, it may have been smashed
2100 to agree with what X says. */
2105 tree name = DECL_NAME (x);
2106 struct c_scope *scope = current_scope;
2107 struct c_binding *b;
2108 bool nested = false;
2110 /* Functions need the lang_decl data. */
2111 if (TREE_CODE (x) == FUNCTION_DECL && !DECL_LANG_SPECIFIC (x))
2112 DECL_LANG_SPECIFIC (x) = GGC_CNEW (struct lang_decl);
2114 /* Must set DECL_CONTEXT for everything not at file scope or
2115 DECL_FILE_SCOPE_P won't work. Local externs don't count
2116 unless they have initializers (which generate code). */
2117 if (current_function_decl
2118 && ((TREE_CODE (x) != FUNCTION_DECL && TREE_CODE (x) != VAR_DECL)
2119 || DECL_INITIAL (x) || !DECL_EXTERNAL (x)))
2120 DECL_CONTEXT (x) = current_function_decl;
2122 /* If this is of variably modified type, prevent jumping into its
2124 if ((TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == TYPE_DECL)
2125 && variably_modified_type_p (TREE_TYPE (x), NULL_TREE))
2126 c_begin_vm_scope (scope->depth);
2128 /* Anonymous decls are just inserted in the scope. */
2131 bind (name, x, scope, /*invisible=*/false, /*nested=*/false);
2135 /* First, see if there is another declaration with the same name in
2136 the current scope. If there is, duplicate_decls may do all the
2137 work for us. If duplicate_decls returns false, that indicates
2138 two incompatible decls in the same scope; we are to silently
2139 replace the old one (duplicate_decls has issued all appropriate
2140 diagnostics). In particular, we should not consider possible
2141 duplicates in the external scope, or shadowing. */
2142 b = I_SYMBOL_BINDING (name);
2143 if (b && B_IN_SCOPE (b, scope))
2145 struct c_binding *b_ext, *b_use;
2146 tree type = TREE_TYPE (x);
2147 tree visdecl = b->decl;
2148 tree vistype = TREE_TYPE (visdecl);
2149 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
2150 && COMPLETE_TYPE_P (TREE_TYPE (x)))
2151 b->inner_comp = false;
2154 /* If this is an external linkage declaration, we should check
2155 for compatibility with the type in the external scope before
2156 setting the type at this scope based on the visible
2157 information only. */
2158 if (TREE_PUBLIC (x) && TREE_PUBLIC (visdecl))
2160 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
2161 b_ext = b_ext->shadowed;
2166 TREE_TYPE (b_use->decl) = b_use->type;
2169 if (duplicate_decls (x, b_use->decl))
2173 /* Save the updated type in the external scope and
2174 restore the proper type for this scope. */
2176 if (comptypes (vistype, type))
2177 thistype = composite_type (vistype, type);
2179 thistype = TREE_TYPE (b_use->decl);
2180 b_use->type = TREE_TYPE (b_use->decl);
2181 if (TREE_CODE (b_use->decl) == FUNCTION_DECL
2182 && DECL_BUILT_IN (b_use->decl))
2184 = build_type_attribute_variant (thistype,
2187 TREE_TYPE (b_use->decl) = thistype;
2192 goto skip_external_and_shadow_checks;
2195 /* All declarations with external linkage, and all external
2196 references, go in the external scope, no matter what scope is
2197 current. However, the binding in that scope is ignored for
2198 purposes of normal name lookup. A separate binding structure is
2199 created in the requested scope; this governs the normal
2200 visibility of the symbol.
2202 The binding in the externals scope is used exclusively for
2203 detecting duplicate declarations of the same object, no matter
2204 what scope they are in; this is what we do here. (C99 6.2.7p2:
2205 All declarations that refer to the same object or function shall
2206 have compatible type; otherwise, the behavior is undefined.) */
2207 if (DECL_EXTERNAL (x) || scope == file_scope)
2209 tree type = TREE_TYPE (x);
2212 bool type_saved = false;
2213 if (b && !B_IN_EXTERNAL_SCOPE (b)
2214 && (TREE_CODE (b->decl) == FUNCTION_DECL
2215 || TREE_CODE (b->decl) == VAR_DECL)
2216 && DECL_FILE_SCOPE_P (b->decl))
2219 vistype = TREE_TYPE (visdecl);
2221 if (scope != file_scope
2222 && !DECL_IN_SYSTEM_HEADER (x))
2223 warning (OPT_Wnested_externs, "nested extern declaration of %qD", x);
2225 while (b && !B_IN_EXTERNAL_SCOPE (b))
2227 /* If this decl might be modified, save its type. This is
2228 done here rather than when the decl is first bound
2229 because the type may change after first binding, through
2230 being completed or through attributes being added. If we
2231 encounter multiple such decls, only the first should have
2232 its type saved; the others will already have had their
2233 proper types saved and the types will not have changed as
2234 their scopes will not have been re-entered. */
2235 if (DECL_P (b->decl) && DECL_FILE_SCOPE_P (b->decl) && !type_saved)
2237 b->type = TREE_TYPE (b->decl);
2240 if (B_IN_FILE_SCOPE (b)
2241 && TREE_CODE (b->decl) == VAR_DECL
2242 && TREE_STATIC (b->decl)
2243 && TREE_CODE (TREE_TYPE (b->decl)) == ARRAY_TYPE
2244 && !TYPE_DOMAIN (TREE_TYPE (b->decl))
2245 && TREE_CODE (type) == ARRAY_TYPE
2246 && TYPE_DOMAIN (type)
2247 && TYPE_MAX_VALUE (TYPE_DOMAIN (type))
2248 && !integer_zerop (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
2250 /* Array type completed in inner scope, which should be
2251 diagnosed if the completion does not have size 1 and
2252 it does not get completed in the file scope. */
2253 b->inner_comp = true;
2258 /* If a matching external declaration has been found, set its
2259 type to the composite of all the types of that declaration.
2260 After the consistency checks, it will be reset to the
2261 composite of the visible types only. */
2262 if (b && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2264 TREE_TYPE (b->decl) = b->type;
2266 /* The point of the same_translation_unit_p check here is,
2267 we want to detect a duplicate decl for a construct like
2268 foo() { extern bar(); } ... static bar(); but not if
2269 they are in different translation units. In any case,
2270 the static does not go in the externals scope. */
2272 && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2273 && duplicate_decls (x, b->decl))
2278 if (comptypes (vistype, type))
2279 thistype = composite_type (vistype, type);
2281 thistype = TREE_TYPE (b->decl);
2285 b->type = TREE_TYPE (b->decl);
2286 if (TREE_CODE (b->decl) == FUNCTION_DECL && DECL_BUILT_IN (b->decl))
2288 = build_type_attribute_variant (thistype,
2289 TYPE_ATTRIBUTES (b->type));
2290 TREE_TYPE (b->decl) = thistype;
2291 bind (name, b->decl, scope, /*invisible=*/false, /*nested=*/true);
2294 else if (TREE_PUBLIC (x))
2296 if (visdecl && !b && duplicate_decls (x, visdecl))
2298 /* An external declaration at block scope referring to a
2299 visible entity with internal linkage. The composite
2300 type will already be correct for this scope, so we
2301 just need to fall through to make the declaration in
2308 bind (name, x, external_scope, /*invisible=*/true,
2315 if (TREE_CODE (x) != PARM_DECL)
2316 warn_if_shadowing (x);
2318 skip_external_and_shadow_checks:
2319 if (TREE_CODE (x) == TYPE_DECL)
2320 clone_underlying_type (x);
2322 bind (name, x, scope, /*invisible=*/false, nested);
2324 /* If x's type is incomplete because it's based on a
2325 structure or union which has not yet been fully declared,
2326 attach it to that structure or union type, so we can go
2327 back and complete the variable declaration later, if the
2328 structure or union gets fully declared.
2330 If the input is erroneous, we can have error_mark in the type
2331 slot (e.g. "f(void a, ...)") - that doesn't count as an
2333 if (TREE_TYPE (x) != error_mark_node
2334 && !COMPLETE_TYPE_P (TREE_TYPE (x)))
2336 tree element = TREE_TYPE (x);
2338 while (TREE_CODE (element) == ARRAY_TYPE)
2339 element = TREE_TYPE (element);
2340 element = TYPE_MAIN_VARIANT (element);
2342 if ((TREE_CODE (element) == RECORD_TYPE
2343 || TREE_CODE (element) == UNION_TYPE)
2344 && (TREE_CODE (x) != TYPE_DECL
2345 || TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE)
2346 && !COMPLETE_TYPE_P (element))
2347 C_TYPE_INCOMPLETE_VARS (element)
2348 = tree_cons (NULL_TREE, x, C_TYPE_INCOMPLETE_VARS (element));
2353 /* Record X as belonging to file scope.
2354 This is used only internally by the Objective-C front end,
2355 and is limited to its needs. duplicate_decls is not called;
2356 if there is any preexisting decl for this identifier, it is an ICE. */
2359 pushdecl_top_level (tree x)
2362 bool nested = false;
2363 gcc_assert (TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == CONST_DECL);
2365 name = DECL_NAME (x);
2367 gcc_assert (TREE_CODE (x) == CONST_DECL || !I_SYMBOL_BINDING (name));
2369 if (TREE_PUBLIC (x))
2371 bind (name, x, external_scope, /*invisible=*/true, /*nested=*/false);
2375 bind (name, x, file_scope, /*invisible=*/false, nested);
2381 implicit_decl_warning (tree id, tree olddecl)
2383 void (*diag) (const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2);
2384 switch (mesg_implicit_function_declaration)
2387 case 1: diag = warning0; break;
2388 case 2: diag = error; break;
2389 default: gcc_unreachable ();
2392 diag (G_("implicit declaration of function %qE"), id);
2394 locate_old_decl (olddecl, diag);
2397 /* Generate an implicit declaration for identifier FUNCTIONID as a
2398 function of type int (). */
2401 implicitly_declare (tree functionid)
2403 struct c_binding *b;
2407 for (b = I_SYMBOL_BINDING (functionid); b; b = b->shadowed)
2409 if (B_IN_SCOPE (b, external_scope))
2418 if (decl == error_mark_node)
2421 /* FIXME: Objective-C has weird not-really-builtin functions
2422 which are supposed to be visible automatically. They wind up
2423 in the external scope because they're pushed before the file
2424 scope gets created. Catch this here and rebind them into the
2426 if (!DECL_BUILT_IN (decl) && DECL_IS_BUILTIN (decl))
2428 bind (functionid, decl, file_scope,
2429 /*invisible=*/false, /*nested=*/true);
2434 tree newtype = default_function_type;
2436 TREE_TYPE (decl) = b->type;
2437 /* Implicit declaration of a function already declared
2438 (somehow) in a different scope, or as a built-in.
2439 If this is the first time this has happened, warn;
2440 then recycle the old declaration but with the new type. */
2441 if (!C_DECL_IMPLICIT (decl))
2443 implicit_decl_warning (functionid, decl);
2444 C_DECL_IMPLICIT (decl) = 1;
2446 if (DECL_BUILT_IN (decl))
2448 newtype = build_type_attribute_variant (newtype,
2450 (TREE_TYPE (decl)));
2451 if (!comptypes (newtype, TREE_TYPE (decl)))
2453 warning (0, "incompatible implicit declaration of built-in"
2454 " function %qD", decl);
2455 newtype = TREE_TYPE (decl);
2460 if (!comptypes (newtype, TREE_TYPE (decl)))
2462 error ("incompatible implicit declaration of function %qD",
2464 locate_old_decl (decl, error);
2467 b->type = TREE_TYPE (decl);
2468 TREE_TYPE (decl) = newtype;
2469 bind (functionid, decl, current_scope,
2470 /*invisible=*/false, /*nested=*/true);
2475 /* Not seen before. */
2476 decl = build_decl (FUNCTION_DECL, functionid, default_function_type);
2477 DECL_EXTERNAL (decl) = 1;
2478 TREE_PUBLIC (decl) = 1;
2479 C_DECL_IMPLICIT (decl) = 1;
2480 implicit_decl_warning (functionid, 0);
2481 asmspec_tree = maybe_apply_renaming_pragma (decl, /*asmname=*/NULL);
2483 set_user_assembler_name (decl, TREE_STRING_POINTER (asmspec_tree));
2485 /* C89 says implicit declarations are in the innermost block.
2486 So we record the decl in the standard fashion. */
2487 decl = pushdecl (decl);
2489 /* No need to call objc_check_decl here - it's a function type. */
2490 rest_of_decl_compilation (decl, 0, 0);
2492 /* Write a record describing this implicit function declaration
2493 to the prototypes file (if requested). */
2494 gen_aux_info_record (decl, 0, 1, 0);
2496 /* Possibly apply some default attributes to this implicit declaration. */
2497 decl_attributes (&decl, NULL_TREE, 0);
2502 /* Issue an error message for a reference to an undeclared variable
2503 ID, including a reference to a builtin outside of function-call
2504 context. Establish a binding of the identifier to error_mark_node
2505 in an appropriate scope, which will suppress further errors for the
2506 same identifier. The error message should be given location LOC. */
2508 undeclared_variable (tree id, location_t loc)
2510 static bool already = false;
2511 struct c_scope *scope;
2513 if (current_function_decl == 0)
2515 error ("%H%qE undeclared here (not in a function)", &loc, id);
2516 scope = current_scope;
2520 error ("%H%qE undeclared (first use in this function)", &loc, id);
2524 error ("%H(Each undeclared identifier is reported only once", &loc);
2525 error ("%Hfor each function it appears in.)", &loc);
2529 /* If we are parsing old-style parameter decls, current_function_decl
2530 will be nonnull but current_function_scope will be null. */
2531 scope = current_function_scope ? current_function_scope : current_scope;
2533 bind (id, error_mark_node, scope, /*invisible=*/false, /*nested=*/false);
2536 /* Subroutine of lookup_label, declare_label, define_label: construct a
2537 LABEL_DECL with all the proper frills. */
2540 make_label (tree name, location_t location)
2542 tree label = build_decl (LABEL_DECL, name, void_type_node);
2544 DECL_CONTEXT (label) = current_function_decl;
2545 DECL_MODE (label) = VOIDmode;
2546 DECL_SOURCE_LOCATION (label) = location;
2551 /* Get the LABEL_DECL corresponding to identifier NAME as a label.
2552 Create one if none exists so far for the current function.
2553 This is called when a label is used in a goto expression or
2554 has its address taken. */
2557 lookup_label (tree name)
2561 if (current_function_decl == 0)
2563 error ("label %qE referenced outside of any function", name);
2567 /* Use a label already defined or ref'd with this name, but not if
2568 it is inherited from a containing function and wasn't declared
2570 label = I_LABEL_DECL (name);
2571 if (label && (DECL_CONTEXT (label) == current_function_decl
2572 || C_DECLARED_LABEL_FLAG (label)))
2574 /* If the label has only been declared, update its apparent
2575 location to point here, for better diagnostics if it
2576 turns out not to have been defined. */
2577 if (!TREE_USED (label))
2578 DECL_SOURCE_LOCATION (label) = input_location;
2582 /* No label binding for that identifier; make one. */
2583 label = make_label (name, input_location);
2585 /* Ordinary labels go in the current function scope. */
2586 bind (name, label, current_function_scope,
2587 /*invisible=*/false, /*nested=*/false);
2591 /* Make a label named NAME in the current function, shadowing silently
2592 any that may be inherited from containing functions or containing
2593 scopes. This is called for __label__ declarations. */
2596 declare_label (tree name)
2598 struct c_binding *b = I_LABEL_BINDING (name);
2601 /* Check to make sure that the label hasn't already been declared
2603 if (b && B_IN_CURRENT_SCOPE (b))
2605 error ("duplicate label declaration %qE", name);
2606 locate_old_decl (b->decl, error);
2608 /* Just use the previous declaration. */
2612 label = make_label (name, input_location);
2613 C_DECLARED_LABEL_FLAG (label) = 1;
2615 /* Declared labels go in the current scope. */
2616 bind (name, label, current_scope,
2617 /*invisible=*/false, /*nested=*/false);
2621 /* Define a label, specifying the location in the source file.
2622 Return the LABEL_DECL node for the label, if the definition is valid.
2623 Otherwise return 0. */
2626 define_label (location_t location, tree name)
2628 /* Find any preexisting label with this name. It is an error
2629 if that label has already been defined in this function, or
2630 if there is a containing function with a declared label with
2632 tree label = I_LABEL_DECL (name);
2633 struct c_label_list *nlist_se, *nlist_vm;
2636 && ((DECL_CONTEXT (label) == current_function_decl
2637 && DECL_INITIAL (label) != 0)
2638 || (DECL_CONTEXT (label) != current_function_decl
2639 && C_DECLARED_LABEL_FLAG (label))))
2641 error ("%Hduplicate label %qD", &location, label);
2642 locate_old_decl (label, error);
2645 else if (label && DECL_CONTEXT (label) == current_function_decl)
2647 /* The label has been used or declared already in this function,
2648 but not defined. Update its location to point to this
2650 if (C_DECL_UNDEFINABLE_STMT_EXPR (label))
2651 error ("%Jjump into statement expression", label);
2652 if (C_DECL_UNDEFINABLE_VM (label))
2653 error ("%Jjump into scope of identifier with variably modified type",
2655 DECL_SOURCE_LOCATION (label) = location;
2659 /* No label binding for that identifier; make one. */
2660 label = make_label (name, location);
2662 /* Ordinary labels go in the current function scope. */
2663 bind (name, label, current_function_scope,
2664 /*invisible=*/false, /*nested=*/false);
2667 if (!in_system_header && lookup_name (name))
2668 warning (OPT_Wtraditional, "%Htraditional C lacks a separate namespace "
2669 "for labels, identifier %qE conflicts", &location, name);
2671 nlist_se = XOBNEW (&parser_obstack, struct c_label_list);
2672 nlist_se->next = label_context_stack_se->labels_def;
2673 nlist_se->label = label;
2674 label_context_stack_se->labels_def = nlist_se;
2676 nlist_vm = XOBNEW (&parser_obstack, struct c_label_list);
2677 nlist_vm->next = label_context_stack_vm->labels_def;
2678 nlist_vm->label = label;
2679 label_context_stack_vm->labels_def = nlist_vm;
2681 /* Mark label as having been defined. */
2682 DECL_INITIAL (label) = error_mark_node;
2686 /* Given NAME, an IDENTIFIER_NODE,
2687 return the structure (or union or enum) definition for that name.
2688 If THISLEVEL_ONLY is nonzero, searches only the current_scope.
2689 CODE says which kind of type the caller wants;
2690 it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
2691 If the wrong kind of type is found, an error is reported. */
2694 lookup_tag (enum tree_code code, tree name, int thislevel_only)
2696 struct c_binding *b = I_TAG_BINDING (name);
2702 /* We only care about whether it's in this level if
2703 thislevel_only was set or it might be a type clash. */
2704 if (thislevel_only || TREE_CODE (b->decl) != code)
2706 /* For our purposes, a tag in the external scope is the same as
2707 a tag in the file scope. (Primarily relevant to Objective-C
2708 and its builtin structure tags, which get pushed before the
2709 file scope is created.) */
2710 if (B_IN_CURRENT_SCOPE (b)
2711 || (current_scope == file_scope && B_IN_EXTERNAL_SCOPE (b)))
2715 if (thislevel_only && !thislevel)
2718 if (TREE_CODE (b->decl) != code)
2720 /* Definition isn't the kind we were looking for. */
2721 pending_invalid_xref = name;
2722 pending_invalid_xref_location = input_location;
2724 /* If in the same binding level as a declaration as a tag
2725 of a different type, this must not be allowed to
2726 shadow that tag, so give the error immediately.
2727 (For example, "struct foo; union foo;" is invalid.) */
2729 pending_xref_error ();
2734 /* Print an error message now
2735 for a recent invalid struct, union or enum cross reference.
2736 We don't print them immediately because they are not invalid
2737 when used in the `struct foo;' construct for shadowing. */
2740 pending_xref_error (void)
2742 if (pending_invalid_xref != 0)
2743 error ("%H%qE defined as wrong kind of tag",
2744 &pending_invalid_xref_location, pending_invalid_xref);
2745 pending_invalid_xref = 0;
2749 /* Look up NAME in the current scope and its superiors
2750 in the namespace of variables, functions and typedefs.
2751 Return a ..._DECL node of some kind representing its definition,
2752 or return 0 if it is undefined. */
2755 lookup_name (tree name)
2757 struct c_binding *b = I_SYMBOL_BINDING (name);
2758 if (b && !b->invisible)
2763 /* Similar to `lookup_name' but look only at the indicated scope. */
2766 lookup_name_in_scope (tree name, struct c_scope *scope)
2768 struct c_binding *b;
2770 for (b = I_SYMBOL_BINDING (name); b; b = b->shadowed)
2771 if (B_IN_SCOPE (b, scope))
2776 /* Create the predefined scalar types of C,
2777 and some nodes representing standard constants (0, 1, (void *) 0).
2778 Initialize the global scope.
2779 Make definitions for built-in primitive functions. */
2782 c_init_decl_processing (void)
2784 location_t save_loc = input_location;
2786 /* Initialize reserved words for parser. */
2789 current_function_decl = 0;
2791 gcc_obstack_init (&parser_obstack);
2793 /* Make the externals scope. */
2795 external_scope = current_scope;
2797 /* Declarations from c_common_nodes_and_builtins must not be associated
2798 with this input file, lest we get differences between using and not
2799 using preprocessed headers. */
2800 #ifdef USE_MAPPED_LOCATION
2801 input_location = BUILTINS_LOCATION;
2803 input_location.file = "<built-in>";
2804 input_location.line = 0;
2807 build_common_tree_nodes (flag_signed_char, false);
2809 c_common_nodes_and_builtins ();
2811 /* In C, comparisons and TRUTH_* expressions have type int. */
2812 truthvalue_type_node = integer_type_node;
2813 truthvalue_true_node = integer_one_node;
2814 truthvalue_false_node = integer_zero_node;
2816 /* Even in C99, which has a real boolean type. */
2817 pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
2818 boolean_type_node));
2820 input_location = save_loc;
2822 pedantic_lvalues = true;
2824 make_fname_decl = c_make_fname_decl;
2825 start_fname_decls ();
2828 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
2829 decl, NAME is the initialization string and TYPE_DEP indicates whether
2830 NAME depended on the type of the function. As we don't yet implement
2831 delayed emission of static data, we mark the decl as emitted
2832 so it is not placed in the output. Anything using it must therefore pull
2833 out the STRING_CST initializer directly. FIXME. */
2836 c_make_fname_decl (tree id, int type_dep)
2838 const char *name = fname_as_string (type_dep);
2839 tree decl, type, init;
2840 size_t length = strlen (name);
2842 type = build_array_type (char_type_node,
2843 build_index_type (size_int (length)));
2844 type = c_build_qualified_type (type, TYPE_QUAL_CONST);
2846 decl = build_decl (VAR_DECL, id, type);
2848 TREE_STATIC (decl) = 1;
2849 TREE_READONLY (decl) = 1;
2850 DECL_ARTIFICIAL (decl) = 1;
2852 init = build_string (length + 1, name);
2853 free ((char *) name);
2854 TREE_TYPE (init) = type;
2855 DECL_INITIAL (decl) = init;
2857 TREE_USED (decl) = 1;
2859 if (current_function_decl
2860 /* For invalid programs like this:
2863 const char* p = __FUNCTION__;
2865 the __FUNCTION__ is believed to appear in K&R style function
2866 parameter declarator. In that case we still don't have
2868 && (!errorcount || current_function_scope))
2870 DECL_CONTEXT (decl) = current_function_decl;
2871 bind (id, decl, current_function_scope,
2872 /*invisible=*/false, /*nested=*/false);
2875 finish_decl (decl, init, NULL_TREE);
2881 c_builtin_function (tree decl)
2883 tree type = TREE_TYPE (decl);
2884 tree id = DECL_NAME (decl);
2886 const char *name = IDENTIFIER_POINTER (id);
2887 DECL_LANG_SPECIFIC (decl) = GGC_CNEW (struct lang_decl);
2888 C_DECL_BUILTIN_PROTOTYPE (decl) = (TYPE_ARG_TYPES (type) != 0);
2890 /* Should never be called on a symbol with a preexisting meaning. */
2891 gcc_assert (!I_SYMBOL_BINDING (id));
2893 bind (id, decl, external_scope, /*invisible=*/true, /*nested=*/false);
2895 /* Builtins in the implementation namespace are made visible without
2896 needing to be explicitly declared. See push_file_scope. */
2897 if (name[0] == '_' && (name[1] == '_' || ISUPPER (name[1])))
2899 TREE_CHAIN (decl) = visible_builtins;
2900 visible_builtins = decl;
2906 /* Called when a declaration is seen that contains no names to declare.
2907 If its type is a reference to a structure, union or enum inherited
2908 from a containing scope, shadow that tag name for the current scope
2909 with a forward reference.
2910 If its type defines a new named structure or union
2911 or defines an enum, it is valid but we need not do anything here.
2912 Otherwise, it is an error. */
2915 shadow_tag (const struct c_declspecs *declspecs)
2917 shadow_tag_warned (declspecs, 0);
2920 /* WARNED is 1 if we have done a pedwarn, 2 if we have done a warning,
2923 shadow_tag_warned (const struct c_declspecs *declspecs, int warned)
2925 bool found_tag = false;
2927 if (declspecs->type && !declspecs->default_int_p && !declspecs->typedef_p)
2929 tree value = declspecs->type;
2930 enum tree_code code = TREE_CODE (value);
2932 if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
2933 /* Used to test also that TYPE_SIZE (value) != 0.
2934 That caused warning for `struct foo;' at top level in the file. */
2936 tree name = TYPE_NAME (value);
2943 if (warned != 1 && code != ENUMERAL_TYPE)
2944 /* Empty unnamed enum OK */
2946 pedwarn ("unnamed struct/union that defines no instances");
2950 else if (!declspecs->tag_defined_p
2951 && declspecs->storage_class != csc_none)
2954 pedwarn ("empty declaration with storage class specifier "
2955 "does not redeclare tag");
2957 pending_xref_error ();
2959 else if (!declspecs->tag_defined_p
2960 && (declspecs->const_p
2961 || declspecs->volatile_p
2962 || declspecs->restrict_p))
2965 pedwarn ("empty declaration with type qualifier "
2966 "does not redeclare tag");
2968 pending_xref_error ();
2972 pending_invalid_xref = 0;
2973 t = lookup_tag (code, name, 1);
2977 t = make_node (code);
2984 if (warned != 1 && !in_system_header)
2986 pedwarn ("useless type name in empty declaration");
2991 else if (warned != 1 && !in_system_header && declspecs->typedef_p)
2993 pedwarn ("useless type name in empty declaration");
2997 pending_invalid_xref = 0;
2999 if (declspecs->inline_p)
3001 error ("%<inline%> in empty declaration");
3005 if (current_scope == file_scope && declspecs->storage_class == csc_auto)
3007 error ("%<auto%> in file-scope empty declaration");
3011 if (current_scope == file_scope && declspecs->storage_class == csc_register)
3013 error ("%<register%> in file-scope empty declaration");
3017 if (!warned && !in_system_header && declspecs->storage_class != csc_none)
3019 warning (0, "useless storage class specifier in empty declaration");
3023 if (!warned && !in_system_header && declspecs->thread_p)
3025 warning (0, "useless %<__thread%> in empty declaration");
3029 if (!warned && !in_system_header && (declspecs->const_p
3030 || declspecs->volatile_p
3031 || declspecs->restrict_p))
3033 warning (0, "useless type qualifier in empty declaration");
3040 pedwarn ("empty declaration");
3045 /* Return the qualifiers from SPECS as a bitwise OR of TYPE_QUAL_*
3046 bits. SPECS represents declaration specifiers that the grammar
3047 only permits to contain type qualifiers and attributes. */
3050 quals_from_declspecs (const struct c_declspecs *specs)
3052 int quals = ((specs->const_p ? TYPE_QUAL_CONST : 0)
3053 | (specs->volatile_p ? TYPE_QUAL_VOLATILE : 0)
3054 | (specs->restrict_p ? TYPE_QUAL_RESTRICT : 0));
3055 gcc_assert (!specs->type
3056 && !specs->decl_attr
3057 && specs->typespec_word == cts_none
3058 && specs->storage_class == csc_none
3059 && !specs->typedef_p
3060 && !specs->explicit_signed_p
3061 && !specs->deprecated_p
3063 && !specs->long_long_p
3066 && !specs->unsigned_p
3067 && !specs->complex_p
3069 && !specs->thread_p);
3073 /* Construct an array declarator. EXPR is the expression inside [],
3074 or NULL_TREE. QUALS are the type qualifiers inside the [] (to be
3075 applied to the pointer to which a parameter array is converted).
3076 STATIC_P is true if "static" is inside the [], false otherwise.
3077 VLA_UNSPEC_P is true if the array is [*], a VLA of unspecified
3078 length which is nevertheless a complete type, false otherwise. The
3079 field for the contained declarator is left to be filled in by
3080 set_array_declarator_inner. */
3082 struct c_declarator *
3083 build_array_declarator (tree expr, struct c_declspecs *quals, bool static_p,
3086 struct c_declarator *declarator = XOBNEW (&parser_obstack,
3087 struct c_declarator);
3088 declarator->kind = cdk_array;
3089 declarator->declarator = 0;
3090 declarator->u.array.dimen = expr;
3093 declarator->u.array.attrs = quals->attrs;
3094 declarator->u.array.quals = quals_from_declspecs (quals);
3098 declarator->u.array.attrs = NULL_TREE;
3099 declarator->u.array.quals = 0;
3101 declarator->u.array.static_p = static_p;
3102 declarator->u.array.vla_unspec_p = vla_unspec_p;
3103 if (pedantic && !flag_isoc99)
3105 if (static_p || quals != NULL)
3106 pedwarn ("ISO C90 does not support %<static%> or type "
3107 "qualifiers in parameter array declarators");
3109 pedwarn ("ISO C90 does not support %<[*]%> array declarators");
3113 if (!current_scope->parm_flag)
3116 error ("%<[*]%> not allowed in other than function prototype scope");
3117 declarator->u.array.vla_unspec_p = false;
3120 current_scope->had_vla_unspec = true;
3125 /* Set the contained declarator of an array declarator. DECL is the
3126 declarator, as constructed by build_array_declarator; INNER is what
3127 appears on the left of the []. ABSTRACT_P is true if it is an
3128 abstract declarator, false otherwise; this is used to reject static
3129 and type qualifiers in abstract declarators, where they are not in
3130 the C99 grammar (subject to possible change in DR#289). */
3132 struct c_declarator *
3133 set_array_declarator_inner (struct c_declarator *decl,
3134 struct c_declarator *inner, bool abstract_p)
3136 decl->declarator = inner;
3137 if (abstract_p && (decl->u.array.quals != TYPE_UNQUALIFIED
3138 || decl->u.array.attrs != NULL_TREE
3139 || decl->u.array.static_p))
3140 error ("static or type qualifiers in abstract declarator");
3144 /* INIT is a constructor that forms DECL's initializer. If the final
3145 element initializes a flexible array field, add the size of that
3146 initializer to DECL's size. */
3149 add_flexible_array_elts_to_size (tree decl, tree init)
3153 if (VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (init)))
3156 elt = VEC_last (constructor_elt, CONSTRUCTOR_ELTS (init))->value;
3157 type = TREE_TYPE (elt);
3158 if (TREE_CODE (type) == ARRAY_TYPE
3159 && TYPE_SIZE (type) == NULL_TREE
3160 && TYPE_DOMAIN (type) != NULL_TREE
3161 && TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL_TREE)
3163 complete_array_type (&type, elt, false);
3165 = size_binop (PLUS_EXPR, DECL_SIZE (decl), TYPE_SIZE (type));
3166 DECL_SIZE_UNIT (decl)
3167 = size_binop (PLUS_EXPR, DECL_SIZE_UNIT (decl), TYPE_SIZE_UNIT (type));
3171 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
3174 groktypename (struct c_type_name *type_name)
3177 tree attrs = type_name->specs->attrs;
3179 type_name->specs->attrs = NULL_TREE;
3181 type = grokdeclarator (type_name->declarator, type_name->specs, TYPENAME,
3184 /* Apply attributes. */
3185 decl_attributes (&type, attrs, 0);
3190 /* Decode a declarator in an ordinary declaration or data definition.
3191 This is called as soon as the type information and variable name
3192 have been parsed, before parsing the initializer if any.
3193 Here we create the ..._DECL node, fill in its type,
3194 and put it on the list of decls for the current context.
3195 The ..._DECL node is returned as the value.
3197 Exception: for arrays where the length is not specified,
3198 the type is left null, to be filled in by `finish_decl'.
3200 Function definitions do not come here; they go to start_function
3201 instead. However, external and forward declarations of functions
3202 do go through here. Structure field declarations are done by
3203 grokfield and not through here. */
3206 start_decl (struct c_declarator *declarator, struct c_declspecs *declspecs,
3207 bool initialized, tree attributes)
3212 /* An object declared as __attribute__((deprecated)) suppresses
3213 warnings of uses of other deprecated items. */
3214 if (lookup_attribute ("deprecated", attributes))
3215 deprecated_state = DEPRECATED_SUPPRESS;
3217 decl = grokdeclarator (declarator, declspecs,
3218 NORMAL, initialized, NULL);
3222 deprecated_state = DEPRECATED_NORMAL;
3224 if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
3225 && MAIN_NAME_P (DECL_NAME (decl)))
3226 warning (OPT_Wmain, "%q+D is usually a function", decl);
3229 /* Is it valid for this decl to have an initializer at all?
3230 If not, set INITIALIZED to zero, which will indirectly
3231 tell 'finish_decl' to ignore the initializer once it is parsed. */
3232 switch (TREE_CODE (decl))
3235 error ("typedef %qD is initialized (use __typeof__ instead)", decl);
3240 error ("function %qD is initialized like a variable", decl);
3245 /* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE. */
3246 error ("parameter %qD is initialized", decl);
3251 /* Don't allow initializations for incomplete types except for
3252 arrays which might be completed by the initialization. */
3254 /* This can happen if the array size is an undefined macro.
3255 We already gave a warning, so we don't need another one. */
3256 if (TREE_TYPE (decl) == error_mark_node)
3258 else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
3260 /* A complete type is ok if size is fixed. */
3262 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
3263 || C_DECL_VARIABLE_SIZE (decl))
3265 error ("variable-sized object may not be initialized");
3269 else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
3271 error ("variable %qD has initializer but incomplete type", decl);
3274 else if (C_DECL_VARIABLE_SIZE (decl))
3276 /* Although C99 is unclear about whether incomplete arrays
3277 of VLAs themselves count as VLAs, it does not make
3278 sense to permit them to be initialized given that
3279 ordinary VLAs may not be initialized. */
3280 error ("variable-sized object may not be initialized");
3287 if (current_scope == file_scope)
3288 TREE_STATIC (decl) = 1;
3290 /* Tell 'pushdecl' this is an initialized decl
3291 even though we don't yet have the initializer expression.
3292 Also tell 'finish_decl' it may store the real initializer. */
3293 DECL_INITIAL (decl) = error_mark_node;
3296 /* If this is a function declaration, write a record describing it to the
3297 prototypes file (if requested). */
3299 if (TREE_CODE (decl) == FUNCTION_DECL)
3300 gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);
3302 /* ANSI specifies that a tentative definition which is not merged with
3303 a non-tentative definition behaves exactly like a definition with an
3304 initializer equal to zero. (Section 3.7.2)
3306 -fno-common gives strict ANSI behavior, though this tends to break
3307 a large body of code that grew up without this rule.
3309 Thread-local variables are never common, since there's no entrenched
3310 body of code to break, and it allows more efficient variable references
3311 in the presence of dynamic linking. */
3313 if (TREE_CODE (decl) == VAR_DECL
3315 && TREE_PUBLIC (decl)
3316 && !DECL_THREAD_LOCAL_P (decl)
3318 DECL_COMMON (decl) = 1;
3320 /* Set attributes here so if duplicate decl, will have proper attributes. */
3321 decl_attributes (&decl, attributes, 0);
3323 #if WANT_C99_INLINE_SEMANTICS
3324 /* Handle gnu_inline attribute. */
3325 if (declspecs->inline_p
3327 && TREE_CODE (decl) == FUNCTION_DECL
3328 && lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (decl)))
3330 if (declspecs->storage_class == csc_auto && current_scope != file_scope)
3332 else if (declspecs->storage_class != csc_static)
3333 DECL_EXTERNAL (decl) = !DECL_EXTERNAL (decl);
3335 #endif /* WANT_C99_INLINE_SEMANTICS */
3337 if (TREE_CODE (decl) == FUNCTION_DECL
3338 && targetm.calls.promote_prototypes (TREE_TYPE (decl)))
3340 struct c_declarator *ce = declarator;
3342 if (ce->kind == cdk_pointer)
3343 ce = declarator->declarator;
3344 if (ce->kind == cdk_function)
3346 tree args = ce->u.arg_info->parms;
3347 for (; args; args = TREE_CHAIN (args))
3349 tree type = TREE_TYPE (args);
3350 if (type && INTEGRAL_TYPE_P (type)
3351 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
3352 DECL_ARG_TYPE (args) = integer_type_node;
3357 if (TREE_CODE (decl) == FUNCTION_DECL
3358 && DECL_DECLARED_INLINE_P (decl)
3359 && DECL_UNINLINABLE (decl)
3360 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
3361 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
3364 /* C99 6.7.4p3: An inline definition of a function with external
3365 linkage shall not contain a definition of a modifiable object
3366 with static storage duration... */
3367 if (TREE_CODE (decl) == VAR_DECL
3368 && current_scope != file_scope
3369 && TREE_STATIC (decl)
3370 && DECL_DECLARED_INLINE_P (current_function_decl)
3371 && DECL_EXTERNAL (current_function_decl))
3372 pedwarn ("%q+D is static but declared in inline function %qD "
3373 "which is not static", decl, current_function_decl);
3375 /* Add this decl to the current scope.
3376 TEM may equal DECL or it may be a previous decl of the same name. */
3377 tem = pushdecl (decl);
3379 if (initialized && DECL_EXTERNAL (tem))
3381 DECL_EXTERNAL (tem) = 0;
3382 TREE_STATIC (tem) = 1;
3388 /* Initialize EH if not initialized yet and exceptions are enabled. */
3391 c_maybe_initialize_eh (void)
3393 if (!flag_exceptions || c_eh_initialized_p)
3396 c_eh_initialized_p = true;
3397 eh_personality_libfunc
3398 = init_one_libfunc (USING_SJLJ_EXCEPTIONS
3399 ? "__gcc_personality_sj0"
3400 : "__gcc_personality_v0");
3401 default_init_unwind_resume_libfunc ();
3402 using_eh_for_cleanups ();
3405 /* Finish processing of a declaration;
3406 install its initial value.
3407 If the length of an array type is not known before,
3408 it must be determined now, from the initial value, or it is an error. */
3411 finish_decl (tree decl, tree init, tree asmspec_tree)
3413 tree type = TREE_TYPE (decl);
3414 int was_incomplete = (DECL_SIZE (decl) == 0);
3415 const char *asmspec = 0;
3417 /* If a name was specified, get the string. */
3418 if ((TREE_CODE (decl) == FUNCTION_DECL || TREE_CODE (decl) == VAR_DECL)
3419 && DECL_FILE_SCOPE_P (decl))
3420 asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
3422 asmspec = TREE_STRING_POINTER (asmspec_tree);
3424 /* If `start_decl' didn't like having an initialization, ignore it now. */
3425 if (init != 0 && DECL_INITIAL (decl) == 0)
3428 /* Don't crash if parm is initialized. */
3429 if (TREE_CODE (decl) == PARM_DECL)
3433 store_init_value (decl, init);
3435 if (c_dialect_objc () && (TREE_CODE (decl) == VAR_DECL
3436 || TREE_CODE (decl) == FUNCTION_DECL
3437 || TREE_CODE (decl) == FIELD_DECL))
3438 objc_check_decl (decl);
3440 /* Deduce size of array from initialization, if not already known. */
3441 if (TREE_CODE (type) == ARRAY_TYPE
3442 && TYPE_DOMAIN (type) == 0
3443 && TREE_CODE (decl) != TYPE_DECL)
3446 = (TREE_STATIC (decl)
3447 /* Even if pedantic, an external linkage array
3448 may have incomplete type at first. */
3449 ? pedantic && !TREE_PUBLIC (decl)
3450 : !DECL_EXTERNAL (decl));
3452 = complete_array_type (&TREE_TYPE (decl), DECL_INITIAL (decl),
3455 /* Get the completed type made by complete_array_type. */
3456 type = TREE_TYPE (decl);
3461 error ("initializer fails to determine size of %q+D", decl);
3466 error ("array size missing in %q+D", decl);
3467 /* If a `static' var's size isn't known,
3468 make it extern as well as static, so it does not get
3470 If it is not `static', then do not mark extern;
3471 finish_incomplete_decl will give it a default size
3472 and it will get allocated. */
3473 else if (!pedantic && TREE_STATIC (decl) && !TREE_PUBLIC (decl))
3474 DECL_EXTERNAL (decl) = 1;
3478 error ("zero or negative size array %q+D", decl);
3482 /* For global variables, update the copy of the type that
3483 exists in the binding. */
3484 if (TREE_PUBLIC (decl))
3486 struct c_binding *b_ext = I_SYMBOL_BINDING (DECL_NAME (decl));
3487 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
3488 b_ext = b_ext->shadowed;
3492 b_ext->type = composite_type (b_ext->type, type);
3503 if (DECL_INITIAL (decl))
3504 TREE_TYPE (DECL_INITIAL (decl)) = type;
3506 layout_decl (decl, 0);
3509 if (TREE_CODE (decl) == VAR_DECL)
3511 if (init && TREE_CODE (init) == CONSTRUCTOR)
3512 add_flexible_array_elts_to_size (decl, init);
3514 if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
3515 && COMPLETE_TYPE_P (TREE_TYPE (decl)))
3516 layout_decl (decl, 0);
3518 if (DECL_SIZE (decl) == 0
3519 /* Don't give an error if we already gave one earlier. */
3520 && TREE_TYPE (decl) != error_mark_node
3521 && (TREE_STATIC (decl)
3522 /* A static variable with an incomplete type
3523 is an error if it is initialized.
3524 Also if it is not file scope.
3525 Otherwise, let it through, but if it is not `extern'
3526 then it may cause an error message later. */
3527 ? (DECL_INITIAL (decl) != 0
3528 || !DECL_FILE_SCOPE_P (decl))
3529 /* An automatic variable with an incomplete type
3531 : !DECL_EXTERNAL (decl)))
3533 error ("storage size of %q+D isn%'t known", decl);
3534 TREE_TYPE (decl) = error_mark_node;
3537 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
3538 && DECL_SIZE (decl) != 0)
3540 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
3541 constant_expression_warning (DECL_SIZE (decl));
3543 error ("storage size of %q+D isn%'t constant", decl);
3546 if (TREE_USED (type))
3547 TREE_USED (decl) = 1;
3550 /* If this is a function and an assembler name is specified, reset DECL_RTL
3551 so we can give it its new name. Also, update built_in_decls if it
3552 was a normal built-in. */
3553 if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
3555 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
3556 set_builtin_user_assembler_name (decl, asmspec);
3557 set_user_assembler_name (decl, asmspec);
3560 /* If #pragma weak was used, mark the decl weak now. */
3561 maybe_apply_pragma_weak (decl);
3563 /* Output the assembler code and/or RTL code for variables and functions,
3564 unless the type is an undefined structure or union.
3565 If not, it will get done when the type is completed. */
3567 if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
3569 /* Determine the ELF visibility. */
3570 if (TREE_PUBLIC (decl))
3571 c_determine_visibility (decl);
3573 /* This is a no-op in c-lang.c or something real in objc-act.c. */
3574 if (c_dialect_objc ())
3575 objc_check_decl (decl);
3579 /* If this is not a static variable, issue a warning.
3580 It doesn't make any sense to give an ASMSPEC for an
3581 ordinary, non-register local variable. Historically,
3582 GCC has accepted -- but ignored -- the ASMSPEC in
3584 if (!DECL_FILE_SCOPE_P (decl)
3585 && TREE_CODE (decl) == VAR_DECL
3586 && !C_DECL_REGISTER (decl)
3587 && !TREE_STATIC (decl))
3588 warning (0, "ignoring asm-specifier for non-static local "
3589 "variable %q+D", decl);
3591 set_user_assembler_name (decl, asmspec);
3594 if (DECL_FILE_SCOPE_P (decl))
3596 if (DECL_INITIAL (decl) == NULL_TREE
3597 || DECL_INITIAL (decl) == error_mark_node)
3598 /* Don't output anything
3599 when a tentative file-scope definition is seen.
3600 But at end of compilation, do output code for them. */
3601 DECL_DEFER_OUTPUT (decl) = 1;
3602 rest_of_decl_compilation (decl, true, 0);
3606 /* In conjunction with an ASMSPEC, the `register'
3607 keyword indicates that we should place the variable
3608 in a particular register. */
3609 if (asmspec && C_DECL_REGISTER (decl))
3611 DECL_HARD_REGISTER (decl) = 1;
3612 /* This cannot be done for a structure with volatile
3613 fields, on which DECL_REGISTER will have been
3615 if (!DECL_REGISTER (decl))
3616 error ("cannot put object with volatile field into register");
3619 if (TREE_CODE (decl) != FUNCTION_DECL)
3621 /* If we're building a variable sized type, and we might be
3622 reachable other than via the top of the current binding
3623 level, then create a new BIND_EXPR so that we deallocate
3624 the object at the right time. */
3625 /* Note that DECL_SIZE can be null due to errors. */
3626 if (DECL_SIZE (decl)
3627 && !TREE_CONSTANT (DECL_SIZE (decl))
3628 && STATEMENT_LIST_HAS_LABEL (cur_stmt_list))
3631 bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL);
3632 TREE_SIDE_EFFECTS (bind) = 1;
3634 BIND_EXPR_BODY (bind) = push_stmt_list ();
3636 add_stmt (build_stmt (DECL_EXPR, decl));
3641 if (!DECL_FILE_SCOPE_P (decl))
3643 /* Recompute the RTL of a local array now
3644 if it used to be an incomplete type. */
3646 && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl))
3648 /* If we used it already as memory, it must stay in memory. */
3649 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
3650 /* If it's still incomplete now, no init will save it. */
3651 if (DECL_SIZE (decl) == 0)
3652 DECL_INITIAL (decl) = 0;
3657 /* If this was marked 'used', be sure it will be output. */
3658 if (!flag_unit_at_a_time && lookup_attribute ("used", DECL_ATTRIBUTES (decl)))
3659 mark_decl_referenced (decl);
3661 if (TREE_CODE (decl) == TYPE_DECL)
3663 if (!DECL_FILE_SCOPE_P (decl)
3664 && variably_modified_type_p (TREE_TYPE (decl), NULL_TREE))
3665 add_stmt (build_stmt (DECL_EXPR, decl));
3667 rest_of_decl_compilation (decl, DECL_FILE_SCOPE_P (decl), 0);
3670 /* At the end of a declaration, throw away any variable type sizes
3671 of types defined inside that declaration. There is no use
3672 computing them in the following function definition. */
3673 if (current_scope == file_scope)
3674 get_pending_sizes ();
3676 /* Install a cleanup (aka destructor) if one was given. */
3677 if (TREE_CODE (decl) == VAR_DECL && !TREE_STATIC (decl))
3679 tree attr = lookup_attribute ("cleanup", DECL_ATTRIBUTES (decl));
3682 tree cleanup_id = TREE_VALUE (TREE_VALUE (attr));
3683 tree cleanup_decl = lookup_name (cleanup_id);
3686 /* Build "cleanup(&decl)" for the destructor. */
3687 cleanup = build_unary_op (ADDR_EXPR, decl, 0);
3688 cleanup = build_tree_list (NULL_TREE, cleanup);
3689 cleanup = build_function_call (cleanup_decl, cleanup);
3691 /* Don't warn about decl unused; the cleanup uses it. */
3692 TREE_USED (decl) = 1;
3693 TREE_USED (cleanup_decl) = 1;
3695 /* Initialize EH, if we've been told to do so. */
3696 c_maybe_initialize_eh ();
3698 push_cleanup (decl, cleanup, false);
3703 /* Given a parsed parameter declaration, decode it into a PARM_DECL. */
3706 grokparm (const struct c_parm *parm)
3708 tree decl = grokdeclarator (parm->declarator, parm->specs, PARM, false,
3711 decl_attributes (&decl, parm->attrs, 0);
3716 /* Given a parsed parameter declaration, decode it into a PARM_DECL
3717 and push that on the current scope. */
3720 push_parm_decl (const struct c_parm *parm)
3724 decl = grokdeclarator (parm->declarator, parm->specs, PARM, false, NULL);
3725 decl_attributes (&decl, parm->attrs, 0);
3727 decl = pushdecl (decl);
3729 finish_decl (decl, NULL_TREE, NULL_TREE);
3732 /* Mark all the parameter declarations to date as forward decls.
3733 Also diagnose use of this extension. */
3736 mark_forward_parm_decls (void)
3738 struct c_binding *b;
3740 if (pedantic && !current_scope->warned_forward_parm_decls)
3742 pedwarn ("ISO C forbids forward parameter declarations");
3743 current_scope->warned_forward_parm_decls = true;
3746 for (b = current_scope->bindings; b; b = b->prev)
3747 if (TREE_CODE (b->decl) == PARM_DECL)
3748 TREE_ASM_WRITTEN (b->decl) = 1;
3751 /* Build a COMPOUND_LITERAL_EXPR. TYPE is the type given in the compound
3752 literal, which may be an incomplete array type completed by the
3753 initializer; INIT is a CONSTRUCTOR that initializes the compound
3757 build_compound_literal (tree type, tree init)
3759 /* We do not use start_decl here because we have a type, not a declarator;
3760 and do not use finish_decl because the decl should be stored inside
3761 the COMPOUND_LITERAL_EXPR rather than added elsewhere as a DECL_EXPR. */
3766 if (type == error_mark_node)
3767 return error_mark_node;
3769 decl = build_decl (VAR_DECL, NULL_TREE, type);
3770 DECL_EXTERNAL (decl) = 0;
3771 TREE_PUBLIC (decl) = 0;
3772 TREE_STATIC (decl) = (current_scope == file_scope);
3773 DECL_CONTEXT (decl) = current_function_decl;
3774 TREE_USED (decl) = 1;
3775 TREE_TYPE (decl) = type;
3776 TREE_READONLY (decl) = TYPE_READONLY (type);
3777 store_init_value (decl, init);
3779 if (TREE_CODE (type) == ARRAY_TYPE && !COMPLETE_TYPE_P (type))
3781 int failure = complete_array_type (&TREE_TYPE (decl),
3782 DECL_INITIAL (decl), true);
3783 gcc_assert (!failure);
3785 type = TREE_TYPE (decl);
3786 TREE_TYPE (DECL_INITIAL (decl)) = type;
3789 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
3790 return error_mark_node;
3792 stmt = build_stmt (DECL_EXPR, decl);
3793 complit = build1 (COMPOUND_LITERAL_EXPR, type, stmt);
3794 TREE_SIDE_EFFECTS (complit) = 1;
3796 layout_decl (decl, 0);
3798 if (TREE_STATIC (decl))
3800 /* This decl needs a name for the assembler output. */
3801 set_compound_literal_name (decl);
3802 DECL_DEFER_OUTPUT (decl) = 1;
3803 DECL_COMDAT (decl) = 1;
3804 DECL_ARTIFICIAL (decl) = 1;
3805 DECL_IGNORED_P (decl) = 1;
3807 rest_of_decl_compilation (decl, 1, 0);
3813 /* Determine whether TYPE is a structure with a flexible array member,
3814 or a union containing such a structure (possibly recursively). */
3817 flexible_array_type_p (tree type)
3820 switch (TREE_CODE (type))
3823 x = TYPE_FIELDS (type);
3826 while (TREE_CHAIN (x) != NULL_TREE)
3828 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
3829 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
3830 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
3831 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
3835 for (x = TYPE_FIELDS (type); x != NULL_TREE; x = TREE_CHAIN (x))
3837 if (flexible_array_type_p (TREE_TYPE (x)))
3846 /* Performs sanity checks on the TYPE and WIDTH of the bit-field NAME,
3847 replacing with appropriate values if they are invalid. */
3849 check_bitfield_type_and_width (tree *type, tree *width, const char *orig_name)
3852 unsigned int max_width;
3853 unsigned HOST_WIDE_INT w;
3854 const char *name = orig_name ? orig_name: _("<anonymous>");
3856 /* Detect and ignore out of range field width and process valid
3858 if (!INTEGRAL_TYPE_P (TREE_TYPE (*width))
3859 || TREE_CODE (*width) != INTEGER_CST)
3861 error ("bit-field %qs width not an integer constant", name);
3862 *width = integer_one_node;
3866 constant_expression_warning (*width);
3867 if (tree_int_cst_sgn (*width) < 0)
3869 error ("negative width in bit-field %qs", name);
3870 *width = integer_one_node;
3872 else if (integer_zerop (*width) && orig_name)
3874 error ("zero width for bit-field %qs", name);
3875 *width = integer_one_node;
3879 /* Detect invalid bit-field type. */
3880 if (TREE_CODE (*type) != INTEGER_TYPE
3881 && TREE_CODE (*type) != BOOLEAN_TYPE
3882 && TREE_CODE (*type) != ENUMERAL_TYPE)
3884 error ("bit-field %qs has invalid type", name);
3885 *type = unsigned_type_node;
3888 type_mv = TYPE_MAIN_VARIANT (*type);
3890 && !in_system_header
3891 && type_mv != integer_type_node
3892 && type_mv != unsigned_type_node
3893 && type_mv != boolean_type_node)
3894 pedwarn ("type of bit-field %qs is a GCC extension", name);
3896 if (type_mv == boolean_type_node)
3897 max_width = CHAR_TYPE_SIZE;
3899 max_width = TYPE_PRECISION (*type);
3901 if (0 < compare_tree_int (*width, max_width))
3903 error ("width of %qs exceeds its type", name);
3905 *width = build_int_cst (NULL_TREE, w);
3908 w = tree_low_cst (*width, 1);
3910 if (TREE_CODE (*type) == ENUMERAL_TYPE)
3912 struct lang_type *lt = TYPE_LANG_SPECIFIC (*type);
3914 || w < min_precision (lt->enum_min, TYPE_UNSIGNED (*type))
3915 || w < min_precision (lt->enum_max, TYPE_UNSIGNED (*type)))
3916 warning (0, "%qs is narrower than values of its type", name);
3921 /* Given declspecs and a declarator,
3922 determine the name and type of the object declared
3923 and construct a ..._DECL node for it.
3924 (In one case we can return a ..._TYPE node instead.
3925 For invalid input we sometimes return 0.)
3927 DECLSPECS is a c_declspecs structure for the declaration specifiers.
3929 DECL_CONTEXT says which syntactic context this declaration is in:
3930 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
3931 FUNCDEF for a function definition. Like NORMAL but a few different
3932 error messages in each case. Return value may be zero meaning
3933 this definition is too screwy to try to parse.
3934 PARM for a parameter declaration (either within a function prototype
3935 or before a function body). Make a PARM_DECL, or return void_type_node.
3936 TYPENAME if for a typename (in a cast or sizeof).
3937 Don't make a DECL node; just return the ..._TYPE node.
3938 FIELD for a struct or union field; make a FIELD_DECL.
3939 INITIALIZED is true if the decl has an initializer.
3940 WIDTH is non-NULL for bit-fields, and is a pointer to an INTEGER_CST node
3941 representing the width of the bit-field.
3943 In the TYPENAME case, DECLARATOR is really an absolute declarator.
3944 It may also be so in the PARM case, for a prototype where the
3945 argument type is specified but not the name.
3947 This function is where the complicated C meanings of `static'
3948 and `extern' are interpreted. */
3951 grokdeclarator (const struct c_declarator *declarator,
3952 struct c_declspecs *declspecs,
3953 enum decl_context decl_context, bool initialized, tree *width)
3955 tree type = declspecs->type;
3956 bool threadp = declspecs->thread_p;
3957 enum c_storage_class storage_class = declspecs->storage_class;
3961 int type_quals = TYPE_UNQUALIFIED;
3962 const char *name, *orig_name;
3963 tree typedef_type = 0;
3964 bool funcdef_flag = false;
3965 bool funcdef_syntax = false;
3966 int size_varies = 0;
3967 tree decl_attr = declspecs->decl_attr;
3968 int array_ptr_quals = TYPE_UNQUALIFIED;
3969 tree array_ptr_attrs = NULL_TREE;
3970 int array_parm_static = 0;
3971 bool array_parm_vla_unspec_p = false;
3972 tree returned_attrs = NULL_TREE;
3973 bool bitfield = width != NULL;
3975 struct c_arg_info *arg_info = 0;
3977 if (decl_context == FUNCDEF)
3978 funcdef_flag = true, decl_context = NORMAL;
3980 /* Look inside a declarator for the name being declared
3981 and get it as a string, for an error message. */
3983 const struct c_declarator *decl = declarator;
3992 funcdef_syntax = (decl->kind == cdk_function);
3993 decl = decl->declarator;
3997 decl = decl->declarator;
4002 name = IDENTIFIER_POINTER (decl->u.id);
4014 /* A function definition's declarator must have the form of
4015 a function declarator. */
4017 if (funcdef_flag && !funcdef_syntax)
4020 /* If this looks like a function definition, make it one,
4021 even if it occurs where parms are expected.
4022 Then store_parm_decls will reject it and not use it as a parm. */
4023 if (decl_context == NORMAL && !funcdef_flag && current_scope->parm_flag)
4024 decl_context = PARM;
4026 if (declspecs->deprecated_p && deprecated_state != DEPRECATED_SUPPRESS)
4027 warn_deprecated_use (declspecs->type);
4029 if ((decl_context == NORMAL || decl_context == FIELD)
4030 && current_scope == file_scope
4031 && variably_modified_type_p (type, NULL_TREE))
4033 error ("variably modified %qs at file scope", name);
4034 type = integer_type_node;
4037 typedef_type = type;
4038 size_varies = C_TYPE_VARIABLE_SIZE (type);
4040 /* Diagnose defaulting to "int". */
4042 if (declspecs->default_int_p && !in_system_header)
4044 /* Issue a warning if this is an ISO C 99 program or if
4045 -Wreturn-type and this is a function, or if -Wimplicit;
4046 prefer the former warning since it is more explicit. */
4047 if ((warn_implicit_int || warn_return_type || flag_isoc99)
4049 warn_about_return_type = 1;
4050 else if (warn_implicit_int || flag_isoc99)
4051 pedwarn_c99 ("type defaults to %<int%> in declaration of %qs", name);
4054 /* Adjust the type if a bit-field is being declared,
4055 -funsigned-bitfields applied and the type is not explicitly
4057 if (bitfield && !flag_signed_bitfields && !declspecs->explicit_signed_p
4058 && TREE_CODE (type) == INTEGER_TYPE)
4059 type = c_common_unsigned_type (type);
4061 /* Figure out the type qualifiers for the declaration. There are
4062 two ways a declaration can become qualified. One is something
4063 like `const int i' where the `const' is explicit. Another is
4064 something like `typedef const int CI; CI i' where the type of the
4065 declaration contains the `const'. A third possibility is that
4066 there is a type qualifier on the element type of a typedefed
4067 array type, in which case we should extract that qualifier so
4068 that c_apply_type_quals_to_decls receives the full list of
4069 qualifiers to work with (C90 is not entirely clear about whether
4070 duplicate qualifiers should be diagnosed in this case, but it
4071 seems most appropriate to do so). */
4072 element_type = strip_array_types (type);
4073 constp = declspecs->const_p + TYPE_READONLY (element_type);
4074 restrictp = declspecs->restrict_p + TYPE_RESTRICT (element_type);
4075 volatilep = declspecs->volatile_p + TYPE_VOLATILE (element_type);
4076 if (pedantic && !flag_isoc99)
4079 pedwarn ("duplicate %<const%>");
4081 pedwarn ("duplicate %<restrict%>");
4083 pedwarn ("duplicate %<volatile%>");
4085 if (!flag_gen_aux_info && (TYPE_QUALS (element_type)))
4086 type = TYPE_MAIN_VARIANT (type);
4087 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4088 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4089 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4091 /* Warn about storage classes that are invalid for certain
4092 kinds of declarations (parameters, typenames, etc.). */
4096 || storage_class == csc_auto
4097 || storage_class == csc_register
4098 || storage_class == csc_typedef))
4100 if (storage_class == csc_auto
4101 && (pedantic || current_scope == file_scope))
4102 pedwarn ("function definition declared %<auto%>");
4103 if (storage_class == csc_register)
4104 error ("function definition declared %<register%>");
4105 if (storage_class == csc_typedef)
4106 error ("function definition declared %<typedef%>");
4108 error ("function definition declared %<__thread%>");
4110 if (storage_class == csc_auto
4111 || storage_class == csc_register
4112 || storage_class == csc_typedef)
4113 storage_class = csc_none;
4115 else if (decl_context != NORMAL && (storage_class != csc_none || threadp))
4117 if (decl_context == PARM && storage_class == csc_register)
4121 switch (decl_context)
4124 error ("storage class specified for structure field %qs",
4128 error ("storage class specified for parameter %qs", name);
4131 error ("storage class specified for typename");
4134 storage_class = csc_none;
4138 else if (storage_class == csc_extern
4142 /* 'extern' with initialization is invalid if not at file scope. */
4143 if (current_scope == file_scope)
4145 /* It is fine to have 'extern const' when compiling at C
4146 and C++ intersection. */
4147 if (!(warn_cxx_compat && constp))
4148 warning (0, "%qs initialized and declared %<extern%>", name);
4151 error ("%qs has both %<extern%> and initializer", name);
4153 else if (current_scope == file_scope)
4155 if (storage_class == csc_auto)
4156 error ("file-scope declaration of %qs specifies %<auto%>", name);
4157 if (pedantic && storage_class == csc_register)
4158 pedwarn ("file-scope declaration of %qs specifies %<register%>", name);
4162 if (storage_class == csc_extern && funcdef_flag)
4163 error ("nested function %qs declared %<extern%>", name);
4164 else if (threadp && storage_class == csc_none)
4166 error ("function-scope %qs implicitly auto and declared "
4173 /* Now figure out the structure of the declarator proper.
4174 Descend through it, creating more complex types, until we reach
4175 the declared identifier (or NULL_TREE, in an absolute declarator).
4176 At each stage we maintain an unqualified version of the type
4177 together with any qualifiers that should be applied to it with
4178 c_build_qualified_type; this way, array types including
4179 multidimensional array types are first built up in unqualified
4180 form and then the qualified form is created with
4181 TYPE_MAIN_VARIANT pointing to the unqualified form. */
4183 while (declarator && declarator->kind != cdk_id)
4185 if (type == error_mark_node)
4187 declarator = declarator->declarator;
4191 /* Each level of DECLARATOR is either a cdk_array (for ...[..]),
4192 a cdk_pointer (for *...),
4193 a cdk_function (for ...(...)),
4194 a cdk_attrs (for nested attributes),
4195 or a cdk_id (for the name being declared
4196 or the place in an absolute declarator
4197 where the name was omitted).
4198 For the last case, we have just exited the loop.
4200 At this point, TYPE is the type of elements of an array,
4201 or for a function to return, or for a pointer to point to.
4202 After this sequence of ifs, TYPE is the type of the
4203 array or function or pointer, and DECLARATOR has had its
4204 outermost layer removed. */
4206 if (array_ptr_quals != TYPE_UNQUALIFIED
4207 || array_ptr_attrs != NULL_TREE
4208 || array_parm_static)
4210 /* Only the innermost declarator (making a parameter be of
4211 array type which is converted to pointer type)
4212 may have static or type qualifiers. */
4213 error ("static or type qualifiers in non-parameter array declarator");
4214 array_ptr_quals = TYPE_UNQUALIFIED;
4215 array_ptr_attrs = NULL_TREE;
4216 array_parm_static = 0;
4219 switch (declarator->kind)
4223 /* A declarator with embedded attributes. */
4224 tree attrs = declarator->u.attrs;
4225 const struct c_declarator *inner_decl;
4227 declarator = declarator->declarator;
4228 inner_decl = declarator;
4229 while (inner_decl->kind == cdk_attrs)
4230 inner_decl = inner_decl->declarator;
4231 if (inner_decl->kind == cdk_id)
4232 attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
4233 else if (inner_decl->kind == cdk_function)
4234 attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
4235 else if (inner_decl->kind == cdk_array)
4236 attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
4237 returned_attrs = decl_attributes (&type,
4238 chainon (returned_attrs, attrs),
4244 tree itype = NULL_TREE;
4245 tree size = declarator->u.array.dimen;
4246 /* The index is a signed object `sizetype' bits wide. */
4247 tree index_type = c_common_signed_type (sizetype);
4249 array_ptr_quals = declarator->u.array.quals;
4250 array_ptr_attrs = declarator->u.array.attrs;
4251 array_parm_static = declarator->u.array.static_p;
4252 array_parm_vla_unspec_p = declarator->u.array.vla_unspec_p;
4254 declarator = declarator->declarator;
4256 /* Check for some types that there cannot be arrays of. */
4258 if (VOID_TYPE_P (type))
4260 error ("declaration of %qs as array of voids", name);
4261 type = error_mark_node;
4264 if (TREE_CODE (type) == FUNCTION_TYPE)
4266 error ("declaration of %qs as array of functions", name);
4267 type = error_mark_node;
4270 if (pedantic && !in_system_header && flexible_array_type_p (type))
4271 pedwarn ("invalid use of structure with flexible array member");
4273 if (size == error_mark_node)
4274 type = error_mark_node;
4276 if (type == error_mark_node)
4279 /* If size was specified, set ITYPE to a range-type for
4280 that size. Otherwise, ITYPE remains null. finish_decl
4281 may figure it out from an initial value. */
4285 /* Strip NON_LVALUE_EXPRs since we aren't using as an
4287 STRIP_TYPE_NOPS (size);
4289 if (!INTEGRAL_TYPE_P (TREE_TYPE (size)))
4291 error ("size of array %qs has non-integer type", name);
4292 size = integer_one_node;
4295 if (pedantic && integer_zerop (size))
4296 pedwarn ("ISO C forbids zero-size array %qs", name);
4298 if (TREE_CODE (size) == INTEGER_CST)
4300 constant_expression_warning (size);
4301 if (tree_int_cst_sgn (size) < 0)
4303 error ("size of array %qs is negative", name);
4304 size = integer_one_node;
4307 else if ((decl_context == NORMAL || decl_context == FIELD)
4308 && current_scope == file_scope)
4310 error ("variably modified %qs at file scope", name);
4311 size = integer_one_node;
4315 /* Make sure the array size remains visibly
4316 nonconstant even if it is (eg) a const variable
4317 with known value. */
4320 if (!flag_isoc99 && pedantic)
4322 if (TREE_CONSTANT (size))
4323 pedwarn ("ISO C90 forbids array %qs whose size "
4324 "can%'t be evaluated",
4327 pedwarn ("ISO C90 forbids variable-size array %qs",
4332 if (integer_zerop (size))
4334 /* A zero-length array cannot be represented with
4335 an unsigned index type, which is what we'll
4336 get with build_index_type. Create an
4337 open-ended range instead. */
4338 itype = build_range_type (sizetype, size, NULL_TREE);
4342 /* Arrange for the SAVE_EXPR on the inside of the
4343 MINUS_EXPR, which allows the -1 to get folded
4344 with the +1 that happens when building TYPE_SIZE. */
4346 size = variable_size (size);
4348 /* Compute the maximum valid index, that is, size
4349 - 1. Do the calculation in index_type, so that
4350 if it is a variable the computations will be
4351 done in the proper mode. */
4352 itype = fold_build2 (MINUS_EXPR, index_type,
4353 convert (index_type, size),
4354 convert (index_type,
4357 /* If that overflowed, the array is too big. ???
4358 While a size of INT_MAX+1 technically shouldn't
4359 cause an overflow (because we subtract 1), the
4360 overflow is recorded during the conversion to
4361 index_type, before the subtraction. Handling
4362 this case seems like an unnecessary
4364 if (TREE_CODE (itype) == INTEGER_CST
4365 && TREE_OVERFLOW (itype))
4367 error ("size of array %qs is too large", name);
4368 type = error_mark_node;
4372 itype = build_index_type (itype);
4375 else if (decl_context == FIELD)
4377 if (pedantic && !flag_isoc99 && !in_system_header)
4378 pedwarn ("ISO C90 does not support flexible array members");
4380 /* ISO C99 Flexible array members are effectively
4381 identical to GCC's zero-length array extension. */
4382 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4384 else if (decl_context == PARM)
4386 if (array_parm_vla_unspec_p)
4391 error ("%<[*]%> not allowed in other than a declaration");
4394 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4398 else if (decl_context == TYPENAME)
4400 if (array_parm_vla_unspec_p)
4402 /* The error is printed elsewhere. We use this to
4403 avoid messing up with incomplete array types of
4404 the same type, that would otherwise be modified
4406 itype = build_range_type (sizetype, size_zero_node,
4411 /* Complain about arrays of incomplete types. */
4412 if (!COMPLETE_TYPE_P (type))
4414 error ("array type has incomplete element type");
4415 type = error_mark_node;
4418 /* When itype is NULL, a shared incomplete array type is
4419 returned for all array of a given type. Elsewhere we
4420 make sure we don't complete that type before copying
4421 it, but here we want to make sure we don't ever
4422 modify the shared type, so we gcc_assert (itype)
4424 type = build_array_type (type, itype);
4426 if (type != error_mark_node)
4430 /* It is ok to modify type here even if itype is
4431 NULL: if size_varies, we're in a
4432 multi-dimensional array and the inner type has
4433 variable size, so the enclosing shared array type
4435 if (size && TREE_CODE (size) == INTEGER_CST)
4437 = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4438 C_TYPE_VARIABLE_SIZE (type) = 1;
4441 /* The GCC extension for zero-length arrays differs from
4442 ISO flexible array members in that sizeof yields
4444 if (size && integer_zerop (size))
4447 TYPE_SIZE (type) = bitsize_zero_node;
4448 TYPE_SIZE_UNIT (type) = size_zero_node;
4450 if (array_parm_vla_unspec_p)
4453 /* The type is complete. C99 6.7.5.2p4 */
4454 TYPE_SIZE (type) = bitsize_zero_node;
4455 TYPE_SIZE_UNIT (type) = size_zero_node;
4459 if (decl_context != PARM
4460 && (array_ptr_quals != TYPE_UNQUALIFIED
4461 || array_ptr_attrs != NULL_TREE
4462 || array_parm_static))
4464 error ("static or type qualifiers in non-parameter array declarator");
4465 array_ptr_quals = TYPE_UNQUALIFIED;
4466 array_ptr_attrs = NULL_TREE;
4467 array_parm_static = 0;
4473 /* Say it's a definition only for the declarator closest
4474 to the identifier, apart possibly from some
4476 bool really_funcdef = false;
4480 const struct c_declarator *t = declarator->declarator;
4481 while (t->kind == cdk_attrs)
4483 really_funcdef = (t->kind == cdk_id);
4486 /* Declaring a function type. Make sure we have a valid
4487 type for the function to return. */
4488 if (type == error_mark_node)
4493 /* Warn about some types functions can't return. */
4494 if (TREE_CODE (type) == FUNCTION_TYPE)
4496 error ("%qs declared as function returning a function", name);
4497 type = integer_type_node;
4499 if (TREE_CODE (type) == ARRAY_TYPE)
4501 error ("%qs declared as function returning an array", name);
4502 type = integer_type_node;
4505 /* Construct the function type and go to the next
4506 inner layer of declarator. */
4507 arg_info = declarator->u.arg_info;
4508 arg_types = grokparms (arg_info, really_funcdef);
4510 put_pending_sizes (arg_info->pending_sizes);
4512 /* Type qualifiers before the return type of the function
4513 qualify the return type, not the function type. */
4516 /* Type qualifiers on a function return type are
4517 normally permitted by the standard but have no
4518 effect, so give a warning at -Wreturn-type.
4519 Qualifiers on a void return type are banned on
4520 function definitions in ISO C; GCC used to used
4521 them for noreturn functions. */
4522 if (VOID_TYPE_P (type) && really_funcdef)
4523 pedwarn ("function definition has qualified void return type");
4525 warning (OPT_Wreturn_type,
4526 "type qualifiers ignored on function return type");
4528 type = c_build_qualified_type (type, type_quals);
4530 type_quals = TYPE_UNQUALIFIED;
4532 type = build_function_type (type, arg_types);
4533 declarator = declarator->declarator;
4535 /* Set the TYPE_CONTEXTs for each tagged type which is local to
4536 the formal parameter list of this FUNCTION_TYPE to point to
4537 the FUNCTION_TYPE node itself. */
4541 for (link = arg_info->tags;
4543 link = TREE_CHAIN (link))
4544 TYPE_CONTEXT (TREE_VALUE (link)) = type;
4550 /* Merge any constancy or volatility into the target type
4553 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4555 pedwarn ("ISO C forbids qualified function types");
4557 type = c_build_qualified_type (type, type_quals);
4560 /* When the pointed-to type involves components of variable size,
4561 care must be taken to ensure that the size evaluation code is
4562 emitted early enough to dominate all the possible later uses
4563 and late enough for the variables on which it depends to have
4566 This is expected to happen automatically when the pointed-to
4567 type has a name/declaration of it's own, but special attention
4568 is required if the type is anonymous.
4570 We handle the NORMAL and FIELD contexts here by attaching an
4571 artificial TYPE_DECL to such pointed-to type. This forces the
4572 sizes evaluation at a safe point and ensures it is not deferred
4573 until e.g. within a deeper conditional context.
4575 We expect nothing to be needed here for PARM or TYPENAME.
4576 Pushing a TYPE_DECL at this point for TYPENAME would actually
4577 be incorrect, as we might be in the middle of an expression
4578 with side effects on the pointed-to type size "arguments" prior
4579 to the pointer declaration point and the fake TYPE_DECL in the
4580 enclosing context would force the size evaluation prior to the
4583 if (!TYPE_NAME (type)
4584 && (decl_context == NORMAL || decl_context == FIELD)
4585 && variably_modified_type_p (type, NULL_TREE))
4587 tree decl = build_decl (TYPE_DECL, NULL_TREE, type);
4588 DECL_ARTIFICIAL (decl) = 1;
4590 finish_decl (decl, NULL_TREE, NULL_TREE);
4591 TYPE_NAME (type) = decl;
4594 type = build_pointer_type (type);
4596 /* Process type qualifiers (such as const or volatile)
4597 that were given inside the `*'. */
4598 type_quals = declarator->u.pointer_quals;
4600 declarator = declarator->declarator;
4608 /* Now TYPE has the actual type, apart from any qualifiers in
4611 /* Check the type and width of a bit-field. */
4613 check_bitfield_type_and_width (&type, width, orig_name);
4615 /* Did array size calculations overflow? */
4617 if (TREE_CODE (type) == ARRAY_TYPE
4618 && COMPLETE_TYPE_P (type)
4619 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST
4620 && TREE_OVERFLOW (TYPE_SIZE_UNIT (type)))
4622 error ("size of array %qs is too large", name);
4623 /* If we proceed with the array type as it is, we'll eventually
4624 crash in tree_low_cst(). */
4625 type = error_mark_node;
4628 /* If this is declaring a typedef name, return a TYPE_DECL. */
4630 if (storage_class == csc_typedef)
4633 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4635 pedwarn ("ISO C forbids qualified function types");
4637 type = c_build_qualified_type (type, type_quals);
4638 decl = build_decl (TYPE_DECL, declarator->u.id, type);
4639 if (declspecs->explicit_signed_p)
4640 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
4641 decl_attributes (&decl, returned_attrs, 0);
4642 if (declspecs->inline_p)
4643 pedwarn ("typedef %q+D declared %<inline%>", decl);
4647 /* If this is a type name (such as, in a cast or sizeof),
4648 compute the type and return it now. */
4650 if (decl_context == TYPENAME)
4652 /* Note that the grammar rejects storage classes in typenames
4654 gcc_assert (storage_class == csc_none && !threadp
4655 && !declspecs->inline_p);
4656 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4658 pedwarn ("ISO C forbids const or volatile function types");
4660 type = c_build_qualified_type (type, type_quals);
4661 decl_attributes (&type, returned_attrs, 0);
4665 if (pedantic && decl_context == FIELD
4666 && variably_modified_type_p (type, NULL_TREE))
4669 pedwarn ("a member of a structure or union cannot have a variably modified type");
4672 /* Aside from typedefs and type names (handle above),
4673 `void' at top level (not within pointer)
4674 is allowed only in public variables.
4675 We don't complain about parms either, but that is because
4676 a better error message can be made later. */
4678 if (VOID_TYPE_P (type) && decl_context != PARM
4679 && !((decl_context != FIELD && TREE_CODE (type) != FUNCTION_TYPE)
4680 && (storage_class == csc_extern
4681 || (current_scope == file_scope
4682 && !(storage_class == csc_static
4683 || storage_class == csc_register)))))
4685 error ("variable or field %qs declared void", name);
4686 type = integer_type_node;
4689 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
4690 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
4695 if (decl_context == PARM)
4697 tree type_as_written;
4700 /* A parameter declared as an array of T is really a pointer to T.
4701 One declared as a function is really a pointer to a function. */
4703 if (TREE_CODE (type) == ARRAY_TYPE)
4705 /* Transfer const-ness of array into that of type pointed to. */
4706 type = TREE_TYPE (type);
4708 type = c_build_qualified_type (type, type_quals);
4709 type = build_pointer_type (type);
4710 type_quals = array_ptr_quals;
4712 /* We don't yet implement attributes in this context. */
4713 if (array_ptr_attrs != NULL_TREE)
4714 warning (OPT_Wattributes,
4715 "attributes in parameter array declarator ignored");
4719 else if (TREE_CODE (type) == FUNCTION_TYPE)
4721 if (pedantic && type_quals)
4722 pedwarn ("ISO C forbids qualified function types");
4724 type = c_build_qualified_type (type, type_quals);
4725 type = build_pointer_type (type);
4726 type_quals = TYPE_UNQUALIFIED;
4728 else if (type_quals)
4729 type = c_build_qualified_type (type, type_quals);
4731 type_as_written = type;
4733 decl = build_decl (PARM_DECL, declarator->u.id, type);
4735 C_DECL_VARIABLE_SIZE (decl) = 1;
4737 /* Compute the type actually passed in the parmlist,
4738 for the case where there is no prototype.
4739 (For example, shorts and chars are passed as ints.)
4740 When there is a prototype, this is overridden later. */
4742 if (type == error_mark_node)
4743 promoted_type = type;
4745 promoted_type = c_type_promotes_to (type);
4747 DECL_ARG_TYPE (decl) = promoted_type;
4748 if (declspecs->inline_p)
4749 pedwarn ("parameter %q+D declared %<inline%>", decl);
4751 else if (decl_context == FIELD)
4753 /* Note that the grammar rejects storage classes in typenames
4755 gcc_assert (storage_class == csc_none && !threadp
4756 && !declspecs->inline_p);
4758 /* Structure field. It may not be a function. */
4760 if (TREE_CODE (type) == FUNCTION_TYPE)
4762 error ("field %qs declared as a function", name);
4763 type = build_pointer_type (type);
4765 else if (TREE_CODE (type) != ERROR_MARK
4766 && !COMPLETE_OR_UNBOUND_ARRAY_TYPE_P (type))
4768 error ("field %qs has incomplete type", name);
4769 type = error_mark_node;
4771 type = c_build_qualified_type (type, type_quals);
4772 decl = build_decl (FIELD_DECL, declarator->u.id, type);
4773 DECL_NONADDRESSABLE_P (decl) = bitfield;
4776 C_DECL_VARIABLE_SIZE (decl) = 1;
4778 else if (TREE_CODE (type) == FUNCTION_TYPE)
4780 if (storage_class == csc_register || threadp)
4782 error ("invalid storage class for function %qs", name);
4784 else if (current_scope != file_scope)
4786 /* Function declaration not at file scope. Storage
4787 classes other than `extern' are not allowed, C99
4788 6.7.1p5, and `extern' makes no difference. However,
4789 GCC allows 'auto', perhaps with 'inline', to support
4790 nested functions. */
4791 if (storage_class == csc_auto)
4794 pedwarn ("invalid storage class for function %qs", name);
4796 else if (storage_class == csc_static)
4798 error ("invalid storage class for function %qs", name);
4800 storage_class = declspecs->storage_class = csc_none;
4806 decl = build_decl (FUNCTION_DECL, declarator->u.id, type);
4807 decl = build_decl_attribute_variant (decl, decl_attr);
4809 DECL_LANG_SPECIFIC (decl) = GGC_CNEW (struct lang_decl);
4811 if (pedantic && type_quals && !DECL_IN_SYSTEM_HEADER (decl))
4812 pedwarn ("ISO C forbids qualified function types");
4814 /* GNU C interprets a volatile-qualified function type to indicate
4815 that the function does not return. */
4816 if ((type_quals & TYPE_QUAL_VOLATILE)
4817 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
4818 warning (0, "%<noreturn%> function returns non-void value");
4820 /* Every function declaration is an external reference
4821 (DECL_EXTERNAL) except for those which are not at file
4822 scope and are explicitly declared "auto". This is
4823 forbidden by standard C (C99 6.7.1p5) and is interpreted by
4824 GCC to signify a forward declaration of a nested function. */
4825 if (storage_class == csc_auto && current_scope != file_scope)
4826 DECL_EXTERNAL (decl) = 0;
4827 /* In C99, a function which is declared 'inline' with 'extern'
4828 is not an external reference (which is confusing). It
4829 means that the later definition of the function must be output
4830 in this file, C99 6.7.4p6. In GNU C89, a function declared
4831 'extern inline' is an external reference. */
4832 else if (declspecs->inline_p && storage_class != csc_static)
4833 #if WANT_C99_INLINE_SEMANTICS
4834 DECL_EXTERNAL (decl) = (storage_class == csc_extern) == !flag_isoc99;
4836 DECL_EXTERNAL (decl) = (storage_class == csc_extern);
4839 DECL_EXTERNAL (decl) = !initialized;
4841 /* Record absence of global scope for `static' or `auto'. */
4843 = !(storage_class == csc_static || storage_class == csc_auto);
4845 /* For a function definition, record the argument information
4846 block where store_parm_decls will look for it. */
4848 current_function_arg_info = arg_info;
4850 if (declspecs->default_int_p)
4851 C_FUNCTION_IMPLICIT_INT (decl) = 1;
4853 /* Record presence of `inline', if it is reasonable. */
4854 if (flag_hosted && MAIN_NAME_P (declarator->u.id))
4856 if (declspecs->inline_p)
4857 pedwarn ("cannot inline function %<main%>");
4859 else if (declspecs->inline_p)
4861 /* Record that the function is declared `inline'. */
4862 DECL_DECLARED_INLINE_P (decl) = 1;
4864 /* Do not mark bare declarations as DECL_INLINE. Doing so
4865 in the presence of multiple declarations can result in
4866 the abstract origin pointing between the declarations,
4867 which will confuse dwarf2out. */
4869 DECL_INLINE (decl) = 1;
4871 /* If -finline-functions, assume it can be inlined. This does
4872 two things: let the function be deferred until it is actually
4873 needed, and let dwarf2 know that the function is inlinable. */
4874 else if (flag_inline_trees == 2 && initialized)
4875 DECL_INLINE (decl) = 1;
4879 /* It's a variable. */
4880 /* An uninitialized decl with `extern' is a reference. */
4881 int extern_ref = !initialized && storage_class == csc_extern;
4883 type = c_build_qualified_type (type, type_quals);
4885 /* C99 6.2.2p7: It is invalid (compile-time undefined
4886 behavior) to create an 'extern' declaration for a
4887 variable if there is a global declaration that is
4888 'static' and the global declaration is not visible.
4889 (If the static declaration _is_ currently visible,
4890 the 'extern' declaration is taken to refer to that decl.) */
4891 if (extern_ref && current_scope != file_scope)
4893 tree global_decl = identifier_global_value (declarator->u.id);
4894 tree visible_decl = lookup_name (declarator->u.id);
4897 && global_decl != visible_decl
4898 && TREE_CODE (global_decl) == VAR_DECL
4899 && !TREE_PUBLIC (global_decl))
4900 error ("variable previously declared %<static%> redeclared "
4904 decl = build_decl (VAR_DECL, declarator->u.id, type);
4905 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
4907 C_DECL_VARIABLE_SIZE (decl) = 1;
4909 if (declspecs->inline_p)
4910 pedwarn ("variable %q+D declared %<inline%>", decl);
4912 /* At file scope, an initialized extern declaration may follow
4913 a static declaration. In that case, DECL_EXTERNAL will be
4914 reset later in start_decl. */
4915 DECL_EXTERNAL (decl) = (storage_class == csc_extern);
4917 /* At file scope, the presence of a `static' or `register' storage
4918 class specifier, or the absence of all storage class specifiers
4919 makes this declaration a definition (perhaps tentative). Also,
4920 the absence of `static' makes it public. */
4921 if (current_scope == file_scope)
4923 TREE_PUBLIC (decl) = storage_class != csc_static;
4924 TREE_STATIC (decl) = !extern_ref;
4926 /* Not at file scope, only `static' makes a static definition. */
4929 TREE_STATIC (decl) = (storage_class == csc_static);
4930 TREE_PUBLIC (decl) = extern_ref;
4935 if (targetm.have_tls)
4936 DECL_TLS_MODEL (decl) = decl_default_tls_model (decl);
4938 /* A mere warning is sure to result in improper semantics
4939 at runtime. Don't bother to allow this to compile. */
4940 error ("thread-local storage not supported for this target");
4944 if (storage_class == csc_extern
4945 && variably_modified_type_p (type, NULL_TREE))
4948 error ("object with variably modified type must have no linkage");
4951 /* Record `register' declaration for warnings on &
4952 and in case doing stupid register allocation. */
4954 if (storage_class == csc_register)
4956 C_DECL_REGISTER (decl) = 1;
4957 DECL_REGISTER (decl) = 1;
4960 /* Record constancy and volatility. */
4961 c_apply_type_quals_to_decl (type_quals, decl);
4963 /* If a type has volatile components, it should be stored in memory.
4964 Otherwise, the fact that those components are volatile
4965 will be ignored, and would even crash the compiler.
4966 Of course, this only makes sense on VAR,PARM, and RESULT decl's. */
4967 if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (decl))
4968 && (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL
4969 || TREE_CODE (decl) == RESULT_DECL))
4971 /* It is not an error for a structure with volatile fields to
4972 be declared register, but reset DECL_REGISTER since it
4973 cannot actually go in a register. */
4974 int was_reg = C_DECL_REGISTER (decl);
4975 C_DECL_REGISTER (decl) = 0;
4976 DECL_REGISTER (decl) = 0;
4977 c_mark_addressable (decl);
4978 C_DECL_REGISTER (decl) = was_reg;
4981 /* This is the earliest point at which we might know the assembler
4982 name of a variable. Thus, if it's known before this, die horribly. */
4983 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl));
4985 decl_attributes (&decl, returned_attrs, 0);
4991 /* Decode the parameter-list info for a function type or function definition.
4992 The argument is the value returned by `get_parm_info' (or made in c-parse.c
4993 if there is an identifier list instead of a parameter decl list).
4994 These two functions are separate because when a function returns
4995 or receives functions then each is called multiple times but the order
4996 of calls is different. The last call to `grokparms' is always the one
4997 that contains the formal parameter names of a function definition.
4999 Return a list of arg types to use in the FUNCTION_TYPE for this function.
5001 FUNCDEF_FLAG is true for a function definition, false for
5002 a mere declaration. A nonempty identifier-list gets an error message
5003 when FUNCDEF_FLAG is false. */
5006 grokparms (struct c_arg_info *arg_info, bool funcdef_flag)
5008 tree arg_types = arg_info->types;
5010 if (funcdef_flag && arg_info->had_vla_unspec)
5012 /* A function definition isn't function prototype scope C99 6.2.1p4. */
5014 error ("%<[*]%> not allowed in other than function prototype scope");
5017 if (arg_types == 0 && !funcdef_flag && !in_system_header)
5018 warning (OPT_Wstrict_prototypes,
5019 "function declaration isn%'t a prototype");
5021 if (arg_types == error_mark_node)
5022 return 0; /* don't set TYPE_ARG_TYPES in this case */
5024 else if (arg_types && TREE_CODE (TREE_VALUE (arg_types)) == IDENTIFIER_NODE)
5027 pedwarn ("parameter names (without types) in function declaration");
5029 arg_info->parms = arg_info->types;
5030 arg_info->types = 0;
5035 tree parm, type, typelt;
5036 unsigned int parmno;
5038 /* If there is a parameter of incomplete type in a definition,
5039 this is an error. In a declaration this is valid, and a
5040 struct or union type may be completed later, before any calls
5041 or definition of the function. In the case where the tag was
5042 first declared within the parameter list, a warning has
5043 already been given. If a parameter has void type, then
5044 however the function cannot be defined or called, so
5047 for (parm = arg_info->parms, typelt = arg_types, parmno = 1;
5049 parm = TREE_CHAIN (parm), typelt = TREE_CHAIN (typelt), parmno++)
5051 type = TREE_VALUE (typelt);
5052 if (type == error_mark_node)
5055 if (!COMPLETE_TYPE_P (type))
5059 if (DECL_NAME (parm))
5060 error ("parameter %u (%q+D) has incomplete type",
5063 error ("%Jparameter %u has incomplete type",
5066 TREE_VALUE (typelt) = error_mark_node;
5067 TREE_TYPE (parm) = error_mark_node;
5069 else if (VOID_TYPE_P (type))
5071 if (DECL_NAME (parm))
5072 warning (0, "parameter %u (%q+D) has void type",
5075 warning (0, "%Jparameter %u has void type",
5080 if (DECL_NAME (parm) && TREE_USED (parm))
5081 warn_if_shadowing (parm);
5087 /* Take apart the current scope and return a c_arg_info structure with
5088 info on a parameter list just parsed.
5090 This structure is later fed to 'grokparms' and 'store_parm_decls'.
5092 ELLIPSIS being true means the argument list ended in '...' so don't
5093 append a sentinel (void_list_node) to the end of the type-list. */
5096 get_parm_info (bool ellipsis)
5098 struct c_binding *b = current_scope->bindings;
5099 struct c_arg_info *arg_info = XOBNEW (&parser_obstack,
5106 static bool explained_incomplete_types = false;
5107 bool gave_void_only_once_err = false;
5109 arg_info->parms = 0;
5111 arg_info->types = 0;
5112 arg_info->others = 0;
5113 arg_info->pending_sizes = 0;
5114 arg_info->had_vla_unspec = current_scope->had_vla_unspec;
5116 /* The bindings in this scope must not get put into a block.
5117 We will take care of deleting the binding nodes. */
5118 current_scope->bindings = 0;
5120 /* This function is only called if there was *something* on the
5124 /* A parameter list consisting solely of 'void' indicates that the
5125 function takes no arguments. But if the 'void' is qualified
5126 (by 'const' or 'volatile'), or has a storage class specifier
5127 ('register'), then the behavior is undefined; issue an error.
5128 Typedefs for 'void' are OK (see DR#157). */
5129 if (b->prev == 0 /* one binding */
5130 && TREE_CODE (b->decl) == PARM_DECL /* which is a parameter */
5131 && !DECL_NAME (b->decl) /* anonymous */
5132 && VOID_TYPE_P (TREE_TYPE (b->decl))) /* of void type */
5134 if (TREE_THIS_VOLATILE (b->decl)
5135 || TREE_READONLY (b->decl)
5136 || C_DECL_REGISTER (b->decl))
5137 error ("%<void%> as only parameter may not be qualified");
5139 /* There cannot be an ellipsis. */
5141 error ("%<void%> must be the only parameter");
5143 arg_info->types = void_list_node;
5148 types = void_list_node;
5150 /* Break up the bindings list into parms, tags, types, and others;
5151 apply sanity checks; purge the name-to-decl bindings. */
5154 tree decl = b->decl;
5155 tree type = TREE_TYPE (decl);
5156 const char *keyword;
5158 switch (TREE_CODE (decl))
5163 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
5164 I_SYMBOL_BINDING (b->id) = b->shadowed;
5167 /* Check for forward decls that never got their actual decl. */
5168 if (TREE_ASM_WRITTEN (decl))
5169 error ("parameter %q+D has just a forward declaration", decl);
5170 /* Check for (..., void, ...) and issue an error. */
5171 else if (VOID_TYPE_P (type) && !DECL_NAME (decl))
5173 if (!gave_void_only_once_err)
5175 error ("%<void%> must be the only parameter");
5176 gave_void_only_once_err = true;
5181 /* Valid parameter, add it to the list. */
5182 TREE_CHAIN (decl) = parms;
5185 /* Since there is a prototype, args are passed in their
5186 declared types. The back end may override this later. */
5187 DECL_ARG_TYPE (decl) = type;
5188 types = tree_cons (0, type, types);
5192 case ENUMERAL_TYPE: keyword = "enum"; goto tag;
5193 case UNION_TYPE: keyword = "union"; goto tag;
5194 case RECORD_TYPE: keyword = "struct"; goto tag;
5196 /* Types may not have tag-names, in which case the type
5197 appears in the bindings list with b->id NULL. */
5200 gcc_assert (I_TAG_BINDING (b->id) == b);
5201 I_TAG_BINDING (b->id) = b->shadowed;
5204 /* Warn about any struct, union or enum tags defined in a
5205 parameter list. The scope of such types is limited to
5206 the parameter list, which is rarely if ever desirable
5207 (it's impossible to call such a function with type-
5208 correct arguments). An anonymous union parm type is
5209 meaningful as a GNU extension, so don't warn for that. */
5210 if (TREE_CODE (decl) != UNION_TYPE || b->id != 0)
5213 /* The %s will be one of 'struct', 'union', or 'enum'. */
5214 warning (0, "%<%s %E%> declared inside parameter list",
5217 /* The %s will be one of 'struct', 'union', or 'enum'. */
5218 warning (0, "anonymous %s declared inside parameter list",
5221 if (!explained_incomplete_types)
5223 warning (0, "its scope is only this definition or declaration,"
5224 " which is probably not what you want");
5225 explained_incomplete_types = true;
5229 tags = tree_cons (b->id, decl, tags);
5235 /* CONST_DECLs appear here when we have an embedded enum,
5236 and TYPE_DECLs appear here when we have an embedded struct
5237 or union. No warnings for this - we already warned about the
5238 type itself. FUNCTION_DECLs appear when there is an implicit
5239 function declaration in the parameter list. */
5241 TREE_CHAIN (decl) = others;
5246 /* error_mark_node appears here when we have an undeclared
5247 variable. Just throw it away. */
5250 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
5251 I_SYMBOL_BINDING (b->id) = b->shadowed;
5255 /* Other things that might be encountered. */
5262 b = free_binding_and_advance (b);
5265 arg_info->parms = parms;
5266 arg_info->tags = tags;
5267 arg_info->types = types;
5268 arg_info->others = others;
5269 arg_info->pending_sizes = get_pending_sizes ();
5273 /* Get the struct, enum or union (CODE says which) with tag NAME.
5274 Define the tag as a forward-reference if it is not defined.
5275 Return a c_typespec structure for the type specifier. */
5278 parser_xref_tag (enum tree_code code, tree name)
5280 struct c_typespec ret;
5281 /* If a cross reference is requested, look up the type
5282 already defined for this tag and return it. */
5284 tree ref = lookup_tag (code, name, 0);
5285 /* If this is the right type of tag, return what we found.
5286 (This reference will be shadowed by shadow_tag later if appropriate.)
5287 If this is the wrong type of tag, do not return it. If it was the
5288 wrong type in the same scope, we will have had an error
5289 message already; if in a different scope and declaring
5290 a name, pending_xref_error will give an error message; but if in a
5291 different scope and not declaring a name, this tag should
5292 shadow the previous declaration of a different type of tag, and
5293 this would not work properly if we return the reference found.
5294 (For example, with "struct foo" in an outer scope, "union foo;"
5295 must shadow that tag with a new one of union type.) */
5296 ret.kind = (ref ? ctsk_tagref : ctsk_tagfirstref);
5297 if (ref && TREE_CODE (ref) == code)
5303 /* If no such tag is yet defined, create a forward-reference node
5304 and record it as the "definition".
5305 When a real declaration of this type is found,
5306 the forward-reference will be altered into a real type. */
5308 ref = make_node (code);
5309 if (code == ENUMERAL_TYPE)
5311 /* Give the type a default layout like unsigned int
5312 to avoid crashing if it does not get defined. */
5313 TYPE_MODE (ref) = TYPE_MODE (unsigned_type_node);
5314 TYPE_ALIGN (ref) = TYPE_ALIGN (unsigned_type_node);
5315 TYPE_USER_ALIGN (ref) = 0;
5316 TYPE_UNSIGNED (ref) = 1;
5317 TYPE_PRECISION (ref) = TYPE_PRECISION (unsigned_type_node);
5318 TYPE_MIN_VALUE (ref) = TYPE_MIN_VALUE (unsigned_type_node);
5319 TYPE_MAX_VALUE (ref) = TYPE_MAX_VALUE (unsigned_type_node);
5322 pushtag (name, ref);
5328 /* Get the struct, enum or union (CODE says which) with tag NAME.
5329 Define the tag as a forward-reference if it is not defined.
5330 Return a tree for the type. */
5333 xref_tag (enum tree_code code, tree name)
5335 return parser_xref_tag (code, name).spec;
5338 /* Make sure that the tag NAME is defined *in the current scope*
5339 at least as a forward reference.
5340 CODE says which kind of tag NAME ought to be. */
5343 start_struct (enum tree_code code, tree name)
5345 /* If there is already a tag defined at this scope
5346 (as a forward reference), just return it. */
5351 ref = lookup_tag (code, name, 1);
5352 if (ref && TREE_CODE (ref) == code)
5354 if (TYPE_SIZE (ref))
5356 if (code == UNION_TYPE)
5357 error ("redefinition of %<union %E%>", name);
5359 error ("redefinition of %<struct %E%>", name);
5361 else if (C_TYPE_BEING_DEFINED (ref))
5363 if (code == UNION_TYPE)
5364 error ("nested redefinition of %<union %E%>", name);
5366 error ("nested redefinition of %<struct %E%>", name);
5367 /* Don't create structures that contain themselves. */
5372 /* Otherwise create a forward-reference just so the tag is in scope. */
5374 if (ref == NULL_TREE || TREE_CODE (ref) != code)
5376 ref = make_node (code);
5377 pushtag (name, ref);
5380 C_TYPE_BEING_DEFINED (ref) = 1;
5381 TYPE_PACKED (ref) = flag_pack_struct;
5385 /* Process the specs, declarator and width (NULL if omitted)
5386 of a structure component, returning a FIELD_DECL node.
5387 WIDTH is non-NULL for bit-fields only, and is an INTEGER_CST node.
5389 This is done during the parsing of the struct declaration.
5390 The FIELD_DECL nodes are chained together and the lot of them
5391 are ultimately passed to `build_struct' to make the RECORD_TYPE node. */
5394 grokfield (struct c_declarator *declarator, struct c_declspecs *declspecs,
5399 if (declarator->kind == cdk_id && declarator->u.id == NULL_TREE
5400 && width == NULL_TREE)
5402 /* This is an unnamed decl.
5404 If we have something of the form "union { list } ;" then this
5405 is the anonymous union extension. Similarly for struct.
5407 If this is something of the form "struct foo;", then
5408 If MS extensions are enabled, this is handled as an
5410 Otherwise this is a forward declaration of a structure tag.
5412 If this is something of the form "foo;" and foo is a TYPE_DECL, then
5413 If MS extensions are enabled and foo names a structure, then
5414 again this is an anonymous struct.
5415 Otherwise this is an error.
5417 Oh what a horrid tangled web we weave. I wonder if MS consciously
5418 took this from Plan 9 or if it was an accident of implementation
5419 that took root before someone noticed the bug... */
5421 tree type = declspecs->type;
5422 bool type_ok = (TREE_CODE (type) == RECORD_TYPE
5423 || TREE_CODE (type) == UNION_TYPE);
5427 && (flag_ms_extensions || !declspecs->typedef_p))
5429 if (flag_ms_extensions)
5433 else if (TYPE_NAME (type) == NULL)
5440 pedwarn ("declaration does not declare anything");
5444 pedwarn ("ISO C doesn%'t support unnamed structs/unions");
5447 value = grokdeclarator (declarator, declspecs, FIELD, false,
5448 width ? &width : NULL);
5450 finish_decl (value, NULL_TREE, NULL_TREE);
5451 DECL_INITIAL (value) = width;
5456 /* Generate an error for any duplicate field names in FIELDLIST. Munge
5457 the list such that this does not present a problem later. */
5460 detect_field_duplicates (tree fieldlist)
5465 /* First, see if there are more than "a few" fields.
5466 This is trivially true if there are zero or one fields. */
5469 x = TREE_CHAIN (fieldlist);
5475 } while (timeout > 0 && x);
5477 /* If there were "few" fields, avoid the overhead of allocating
5478 a hash table. Instead just do the nested traversal thing. */
5481 for (x = TREE_CHAIN (fieldlist); x ; x = TREE_CHAIN (x))
5484 for (y = fieldlist; y != x; y = TREE_CHAIN (y))
5485 if (DECL_NAME (y) == DECL_NAME (x))
5487 error ("duplicate member %q+D", x);
5488 DECL_NAME (x) = NULL_TREE;
5494 htab_t htab = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL);
5497 for (x = fieldlist; x ; x = TREE_CHAIN (x))
5498 if ((y = DECL_NAME (x)) != 0)
5500 slot = htab_find_slot (htab, y, INSERT);
5503 error ("duplicate member %q+D", x);
5504 DECL_NAME (x) = NULL_TREE;
5513 /* Fill in the fields of a RECORD_TYPE or UNION_TYPE node, T.
5514 FIELDLIST is a chain of FIELD_DECL nodes for the fields.
5515 ATTRIBUTES are attributes to be applied to the structure. */
5518 finish_struct (tree t, tree fieldlist, tree attributes)
5521 bool toplevel = file_scope == current_scope;
5522 int saw_named_field;
5524 /* If this type was previously laid out as a forward reference,
5525 make sure we lay it out again. */
5529 decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5533 for (x = fieldlist; x; x = TREE_CHAIN (x))
5534 if (DECL_NAME (x) != 0)
5539 if (TREE_CODE (t) == UNION_TYPE)
5542 pedwarn ("union has no named members");
5544 pedwarn ("union has no members");
5549 pedwarn ("struct has no named members");
5551 pedwarn ("struct has no members");
5556 /* Install struct as DECL_CONTEXT of each field decl.
5557 Also process specified field sizes, found in the DECL_INITIAL,
5558 storing 0 there after the type has been changed to precision equal
5559 to its width, rather than the precision of the specified standard
5560 type. (Correct layout requires the original type to have been preserved
5563 saw_named_field = 0;
5564 for (x = fieldlist; x; x = TREE_CHAIN (x))
5566 if (TREE_TYPE (x) == error_mark_node)
5569 DECL_CONTEXT (x) = t;
5571 if (TYPE_PACKED (t) && TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
5572 DECL_PACKED (x) = 1;
5574 /* If any field is const, the structure type is pseudo-const. */
5575 if (TREE_READONLY (x))
5576 C_TYPE_FIELDS_READONLY (t) = 1;
5579 /* A field that is pseudo-const makes the structure likewise. */
5580 tree t1 = TREE_TYPE (x);
5581 while (TREE_CODE (t1) == ARRAY_TYPE)
5582 t1 = TREE_TYPE (t1);
5583 if ((TREE_CODE (t1) == RECORD_TYPE || TREE_CODE (t1) == UNION_TYPE)
5584 && C_TYPE_FIELDS_READONLY (t1))
5585 C_TYPE_FIELDS_READONLY (t) = 1;
5588 /* Any field that is volatile means variables of this type must be
5589 treated in some ways as volatile. */
5590 if (TREE_THIS_VOLATILE (x))
5591 C_TYPE_FIELDS_VOLATILE (t) = 1;
5593 /* Any field of nominal variable size implies structure is too. */
5594 if (C_DECL_VARIABLE_SIZE (x))
5595 C_TYPE_VARIABLE_SIZE (t) = 1;
5597 if (DECL_INITIAL (x))
5599 unsigned HOST_WIDE_INT width = tree_low_cst (DECL_INITIAL (x), 1);
5600 DECL_SIZE (x) = bitsize_int (width);
5601 DECL_BIT_FIELD (x) = 1;
5602 SET_DECL_C_BIT_FIELD (x);
5605 /* Detect flexible array member in an invalid context. */
5606 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
5607 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
5608 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
5609 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
5611 if (TREE_CODE (t) == UNION_TYPE)
5613 error ("%Jflexible array member in union", x);
5614 TREE_TYPE (x) = error_mark_node;
5616 else if (TREE_CHAIN (x) != NULL_TREE)
5618 error ("%Jflexible array member not at end of struct", x);
5619 TREE_TYPE (x) = error_mark_node;
5621 else if (!saw_named_field)
5623 error ("%Jflexible array member in otherwise empty struct", x);
5624 TREE_TYPE (x) = error_mark_node;
5628 if (pedantic && !in_system_header && TREE_CODE (t) == RECORD_TYPE
5629 && flexible_array_type_p (TREE_TYPE (x)))
5630 pedwarn ("%Jinvalid use of structure with flexible array member", x);
5633 saw_named_field = 1;
5636 detect_field_duplicates (fieldlist);
5638 /* Now we have the nearly final fieldlist. Record it,
5639 then lay out the structure or union (including the fields). */
5641 TYPE_FIELDS (t) = fieldlist;
5645 /* Give bit-fields their proper types. */
5647 tree *fieldlistp = &fieldlist;
5649 if (TREE_CODE (*fieldlistp) == FIELD_DECL && DECL_INITIAL (*fieldlistp)
5650 && TREE_TYPE (*fieldlistp) != error_mark_node)
5652 unsigned HOST_WIDE_INT width
5653 = tree_low_cst (DECL_INITIAL (*fieldlistp), 1);
5654 tree type = TREE_TYPE (*fieldlistp);
5655 if (width != TYPE_PRECISION (type))
5657 TREE_TYPE (*fieldlistp)
5658 = c_build_bitfield_integer_type (width, TYPE_UNSIGNED (type));
5659 DECL_MODE (*fieldlistp) = TYPE_MODE (TREE_TYPE (*fieldlistp));
5661 DECL_INITIAL (*fieldlistp) = 0;
5664 fieldlistp = &TREE_CHAIN (*fieldlistp);
5667 /* Now we have the truly final field list.
5668 Store it in this type and in the variants. */
5670 TYPE_FIELDS (t) = fieldlist;
5672 /* If there are lots of fields, sort so we can look through them fast.
5673 We arbitrarily consider 16 or more elts to be "a lot". */
5678 for (x = fieldlist; x; x = TREE_CHAIN (x))
5680 if (len > 15 || DECL_NAME (x) == NULL)
5688 struct lang_type *space;
5689 struct sorted_fields_type *space2;
5691 len += list_length (x);
5693 /* Use the same allocation policy here that make_node uses, to
5694 ensure that this lives as long as the rest of the struct decl.
5695 All decls in an inline function need to be saved. */
5697 space = GGC_CNEW (struct lang_type);
5698 space2 = GGC_NEWVAR (struct sorted_fields_type,
5699 sizeof (struct sorted_fields_type) + len * sizeof (tree));
5703 field_array = &space2->elts[0];
5704 for (x = fieldlist; x; x = TREE_CHAIN (x))
5706 field_array[len++] = x;
5708 /* If there is anonymous struct or union, break out of the loop. */
5709 if (DECL_NAME (x) == NULL)
5712 /* Found no anonymous struct/union. Add the TYPE_LANG_SPECIFIC. */
5715 TYPE_LANG_SPECIFIC (t) = space;
5716 TYPE_LANG_SPECIFIC (t)->s->len = len;
5717 field_array = TYPE_LANG_SPECIFIC (t)->s->elts;
5718 qsort (field_array, len, sizeof (tree), field_decl_cmp);
5723 for (x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
5725 TYPE_FIELDS (x) = TYPE_FIELDS (t);
5726 TYPE_LANG_SPECIFIC (x) = TYPE_LANG_SPECIFIC (t);
5727 C_TYPE_FIELDS_READONLY (x) = C_TYPE_FIELDS_READONLY (t);
5728 C_TYPE_FIELDS_VOLATILE (x) = C_TYPE_FIELDS_VOLATILE (t);
5729 C_TYPE_VARIABLE_SIZE (x) = C_TYPE_VARIABLE_SIZE (t);
5732 /* If this was supposed to be a transparent union, but we can't
5733 make it one, warn and turn off the flag. */
5734 if (TREE_CODE (t) == UNION_TYPE
5735 && TYPE_TRANSPARENT_UNION (t)
5736 && (!TYPE_FIELDS (t) || TYPE_MODE (t) != DECL_MODE (TYPE_FIELDS (t))))
5738 TYPE_TRANSPARENT_UNION (t) = 0;
5739 warning (0, "union cannot be made transparent");
5742 /* If this structure or union completes the type of any previous
5743 variable declaration, lay it out and output its rtl. */
5744 for (x = C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t));
5748 tree decl = TREE_VALUE (x);
5749 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
5750 layout_array_type (TREE_TYPE (decl));
5751 if (TREE_CODE (decl) != TYPE_DECL)
5753 layout_decl (decl, 0);
5754 if (c_dialect_objc ())
5755 objc_check_decl (decl);
5756 rest_of_decl_compilation (decl, toplevel, 0);
5761 C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t)) = 0;
5763 /* Finish debugging output for this type. */
5764 rest_of_type_compilation (t, toplevel);
5766 /* If we're inside a function proper, i.e. not file-scope and not still
5767 parsing parameters, then arrange for the size of a variable sized type
5769 if (cur_stmt_list && variably_modified_type_p (t, NULL_TREE))
5770 add_stmt (build_stmt (DECL_EXPR, build_decl (TYPE_DECL, NULL, t)));
5775 /* Lay out the type T, and its element type, and so on. */
5778 layout_array_type (tree t)
5780 if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
5781 layout_array_type (TREE_TYPE (t));
5785 /* Begin compiling the definition of an enumeration type.
5786 NAME is its name (or null if anonymous).
5787 Returns the type object, as yet incomplete.
5788 Also records info about it so that build_enumerator
5789 may be used to declare the individual values as they are read. */
5792 start_enum (tree name)
5796 /* If this is the real definition for a previous forward reference,
5797 fill in the contents in the same object that used to be the
5798 forward reference. */
5801 enumtype = lookup_tag (ENUMERAL_TYPE, name, 1);
5803 if (enumtype == 0 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
5805 enumtype = make_node (ENUMERAL_TYPE);
5806 pushtag (name, enumtype);
5809 if (C_TYPE_BEING_DEFINED (enumtype))
5810 error ("nested redefinition of %<enum %E%>", name);
5812 C_TYPE_BEING_DEFINED (enumtype) = 1;
5814 if (TYPE_VALUES (enumtype) != 0)
5816 /* This enum is a named one that has been declared already. */
5817 error ("redeclaration of %<enum %E%>", name);
5819 /* Completely replace its old definition.
5820 The old enumerators remain defined, however. */
5821 TYPE_VALUES (enumtype) = 0;
5824 enum_next_value = integer_zero_node;
5827 if (flag_short_enums)
5828 TYPE_PACKED (enumtype) = 1;
5833 /* After processing and defining all the values of an enumeration type,
5834 install their decls in the enumeration type and finish it off.
5835 ENUMTYPE is the type object, VALUES a list of decl-value pairs,
5836 and ATTRIBUTES are the specified attributes.
5837 Returns ENUMTYPE. */
5840 finish_enum (tree enumtype, tree values, tree attributes)
5843 tree minnode = 0, maxnode = 0;
5844 int precision, unsign;
5845 bool toplevel = (file_scope == current_scope);
5846 struct lang_type *lt;
5848 decl_attributes (&enumtype, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5850 /* Calculate the maximum value of any enumerator in this type. */
5852 if (values == error_mark_node)
5853 minnode = maxnode = integer_zero_node;
5856 minnode = maxnode = TREE_VALUE (values);
5857 for (pair = TREE_CHAIN (values); pair; pair = TREE_CHAIN (pair))
5859 tree value = TREE_VALUE (pair);
5860 if (tree_int_cst_lt (maxnode, value))
5862 if (tree_int_cst_lt (value, minnode))
5867 /* Construct the final type of this enumeration. It is the same
5868 as one of the integral types - the narrowest one that fits, except
5869 that normally we only go as narrow as int - and signed iff any of
5870 the values are negative. */
5871 unsign = (tree_int_cst_sgn (minnode) >= 0);
5872 precision = MAX (min_precision (minnode, unsign),
5873 min_precision (maxnode, unsign));
5875 if (TYPE_PACKED (enumtype) || precision > TYPE_PRECISION (integer_type_node))
5877 tem = c_common_type_for_size (precision, unsign);
5880 warning (0, "enumeration values exceed range of largest integer");
5881 tem = long_long_integer_type_node;
5885 tem = unsign ? unsigned_type_node : integer_type_node;
5887 TYPE_MIN_VALUE (enumtype) = TYPE_MIN_VALUE (tem);
5888 TYPE_MAX_VALUE (enumtype) = TYPE_MAX_VALUE (tem);
5889 TYPE_UNSIGNED (enumtype) = TYPE_UNSIGNED (tem);
5890 TYPE_SIZE (enumtype) = 0;
5892 /* If the precision of the type was specific with an attribute and it
5893 was too small, give an error. Otherwise, use it. */
5894 if (TYPE_PRECISION (enumtype))
5896 if (precision > TYPE_PRECISION (enumtype))
5897 error ("specified mode too small for enumeral values");
5900 TYPE_PRECISION (enumtype) = TYPE_PRECISION (tem);
5902 layout_type (enumtype);
5904 if (values != error_mark_node)
5906 /* Change the type of the enumerators to be the enum type. We
5907 need to do this irrespective of the size of the enum, for
5908 proper type checking. Replace the DECL_INITIALs of the
5909 enumerators, and the value slots of the list, with copies
5910 that have the enum type; they cannot be modified in place
5911 because they may be shared (e.g. integer_zero_node) Finally,
5912 change the purpose slots to point to the names of the decls. */
5913 for (pair = values; pair; pair = TREE_CHAIN (pair))
5915 tree enu = TREE_PURPOSE (pair);
5916 tree ini = DECL_INITIAL (enu);
5918 TREE_TYPE (enu) = enumtype;
5920 /* The ISO C Standard mandates enumerators to have type int,
5921 even though the underlying type of an enum type is
5922 unspecified. Here we convert any enumerators that fit in
5923 an int to type int, to avoid promotions to unsigned types
5924 when comparing integers with enumerators that fit in the
5925 int range. When -pedantic is given, build_enumerator()
5926 would have already taken care of those that don't fit. */
5927 if (int_fits_type_p (ini, integer_type_node))
5928 tem = integer_type_node;
5931 ini = convert (tem, ini);
5933 DECL_INITIAL (enu) = ini;
5934 TREE_PURPOSE (pair) = DECL_NAME (enu);
5935 TREE_VALUE (pair) = ini;
5938 TYPE_VALUES (enumtype) = values;
5941 /* Record the min/max values so that we can warn about bit-field
5942 enumerations that are too small for the values. */
5943 lt = GGC_CNEW (struct lang_type);
5944 lt->enum_min = minnode;
5945 lt->enum_max = maxnode;
5946 TYPE_LANG_SPECIFIC (enumtype) = lt;
5948 /* Fix up all variant types of this enum type. */
5949 for (tem = TYPE_MAIN_VARIANT (enumtype); tem; tem = TYPE_NEXT_VARIANT (tem))
5951 if (tem == enumtype)
5953 TYPE_VALUES (tem) = TYPE_VALUES (enumtype);
5954 TYPE_MIN_VALUE (tem) = TYPE_MIN_VALUE (enumtype);
5955 TYPE_MAX_VALUE (tem) = TYPE_MAX_VALUE (enumtype);
5956 TYPE_SIZE (tem) = TYPE_SIZE (enumtype);
5957 TYPE_SIZE_UNIT (tem) = TYPE_SIZE_UNIT (enumtype);
5958 TYPE_MODE (tem) = TYPE_MODE (enumtype);
5959 TYPE_PRECISION (tem) = TYPE_PRECISION (enumtype);
5960 TYPE_ALIGN (tem) = TYPE_ALIGN (enumtype);
5961 TYPE_USER_ALIGN (tem) = TYPE_USER_ALIGN (enumtype);
5962 TYPE_UNSIGNED (tem) = TYPE_UNSIGNED (enumtype);
5963 TYPE_LANG_SPECIFIC (tem) = TYPE_LANG_SPECIFIC (enumtype);
5966 /* Finish debugging output for this type. */
5967 rest_of_type_compilation (enumtype, toplevel);
5972 /* Build and install a CONST_DECL for one value of the
5973 current enumeration type (one that was begun with start_enum).
5974 Return a tree-list containing the CONST_DECL and its value.
5975 Assignment of sequential values by default is handled here. */
5978 build_enumerator (tree name, tree value)
5982 /* Validate and default VALUE. */
5986 /* Don't issue more errors for error_mark_node (i.e. an
5987 undeclared identifier) - just ignore the value expression. */
5988 if (value == error_mark_node)
5990 else if (!INTEGRAL_TYPE_P (TREE_TYPE (value))
5991 || TREE_CODE (value) != INTEGER_CST)
5993 error ("enumerator value for %qE is not an integer constant", name);
5998 value = default_conversion (value);
5999 constant_expression_warning (value);
6003 /* Default based on previous value. */
6004 /* It should no longer be possible to have NON_LVALUE_EXPR
6008 value = enum_next_value;
6010 error ("overflow in enumeration values");
6013 if (pedantic && !int_fits_type_p (value, integer_type_node))
6015 pedwarn ("ISO C restricts enumerator values to range of %<int%>");
6016 /* XXX This causes -pedantic to change the meaning of the program.
6017 Remove? -zw 2004-03-15 */
6018 value = convert (integer_type_node, value);
6021 /* Set basis for default for next value. */
6022 enum_next_value = build_binary_op (PLUS_EXPR, value, integer_one_node, 0);
6023 enum_overflow = tree_int_cst_lt (enum_next_value, value);
6025 /* Now create a declaration for the enum value name. */
6027 type = TREE_TYPE (value);
6028 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
6029 TYPE_PRECISION (integer_type_node)),
6030 (TYPE_PRECISION (type)
6031 >= TYPE_PRECISION (integer_type_node)
6032 && TYPE_UNSIGNED (type)));
6034 decl = build_decl (CONST_DECL, name, type);
6035 DECL_INITIAL (decl) = convert (type, value);
6038 return tree_cons (decl, value, NULL_TREE);
6042 /* Create the FUNCTION_DECL for a function definition.
6043 DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of
6044 the declaration; they describe the function's name and the type it returns,
6045 but twisted together in a fashion that parallels the syntax of C.
6047 This function creates a binding context for the function body
6048 as well as setting up the FUNCTION_DECL in current_function_decl.
6050 Returns 1 on success. If the DECLARATOR is not suitable for a function
6051 (it defines a datum instead), we return 0, which tells
6052 yyparse to report a parse error. */
6055 start_function (struct c_declspecs *declspecs, struct c_declarator *declarator,
6058 tree decl1, old_decl;
6059 tree restype, resdecl;
6060 struct c_label_context_se *nstack_se;
6061 struct c_label_context_vm *nstack_vm;
6063 current_function_returns_value = 0; /* Assume, until we see it does. */
6064 current_function_returns_null = 0;
6065 current_function_returns_abnormally = 0;
6066 warn_about_return_type = 0;
6067 c_switch_stack = NULL;
6069 nstack_se = XOBNEW (&parser_obstack, struct c_label_context_se);
6070 nstack_se->labels_def = NULL;
6071 nstack_se->labels_used = NULL;
6072 nstack_se->next = label_context_stack_se;
6073 label_context_stack_se = nstack_se;
6075 nstack_vm = XOBNEW (&parser_obstack, struct c_label_context_vm);
6076 nstack_vm->labels_def = NULL;
6077 nstack_vm->labels_used = NULL;
6078 nstack_vm->scope = 0;
6079 nstack_vm->next = label_context_stack_vm;
6080 label_context_stack_vm = nstack_vm;
6082 /* Indicate no valid break/continue context by setting these variables
6083 to some non-null, non-label value. We'll notice and emit the proper
6084 error message in c_finish_bc_stmt. */
6085 c_break_label = c_cont_label = size_zero_node;
6087 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, true, NULL);
6089 /* If the declarator is not suitable for a function definition,
6090 cause a syntax error. */
6093 label_context_stack_se = label_context_stack_se->next;
6094 label_context_stack_vm = label_context_stack_vm->next;
6098 decl_attributes (&decl1, attributes, 0);
6100 if (DECL_DECLARED_INLINE_P (decl1)
6101 && DECL_UNINLINABLE (decl1)
6102 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl1)))
6103 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
6106 #if WANT_C99_INLINE_SEMANTICS
6107 /* Handle gnu_inline attribute. */
6108 if (declspecs->inline_p
6110 && TREE_CODE (decl1) == FUNCTION_DECL
6111 && lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (decl1)))
6113 if (declspecs->storage_class != csc_static)
6114 DECL_EXTERNAL (decl1) = !DECL_EXTERNAL (decl1);
6116 #endif /* WANT_C99_INLINE_SEMANTICS */
6118 announce_function (decl1);
6120 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl1))))
6122 error ("return type is an incomplete type");
6123 /* Make it return void instead. */
6125 = build_function_type (void_type_node,
6126 TYPE_ARG_TYPES (TREE_TYPE (decl1)));
6129 if (warn_about_return_type)
6130 pedwarn_c99 ("return type defaults to %<int%>");
6132 /* Make the init_value nonzero so pushdecl knows this is not tentative.
6133 error_mark_node is replaced below (in pop_scope) with the BLOCK. */
6134 DECL_INITIAL (decl1) = error_mark_node;
6136 /* If this definition isn't a prototype and we had a prototype declaration
6137 before, copy the arg type info from that prototype. */
6138 old_decl = lookup_name_in_scope (DECL_NAME (decl1), current_scope);
6139 if (old_decl && TREE_CODE (old_decl) != FUNCTION_DECL)
6141 current_function_prototype_locus = UNKNOWN_LOCATION;
6142 current_function_prototype_built_in = false;
6143 current_function_prototype_arg_types = NULL_TREE;
6144 if (TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0)
6146 if (old_decl != 0 && TREE_CODE (TREE_TYPE (old_decl)) == FUNCTION_TYPE
6147 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
6148 TREE_TYPE (TREE_TYPE (old_decl))))
6150 TREE_TYPE (decl1) = composite_type (TREE_TYPE (old_decl),
6152 current_function_prototype_locus = DECL_SOURCE_LOCATION (old_decl);
6153 current_function_prototype_built_in
6154 = C_DECL_BUILTIN_PROTOTYPE (old_decl);
6155 current_function_prototype_arg_types
6156 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
6158 if (TREE_PUBLIC (decl1))
6160 /* If there is an external prototype declaration of this
6161 function, record its location but do not copy information
6162 to this decl. This may be an invisible declaration
6163 (built-in or in a scope which has finished) or simply
6164 have more refined argument types than any declaration
6166 struct c_binding *b;
6167 for (b = I_SYMBOL_BINDING (DECL_NAME (decl1)); b; b = b->shadowed)
6168 if (B_IN_SCOPE (b, external_scope))
6172 tree ext_decl, ext_type;
6174 ext_type = b->type ? b->type : TREE_TYPE (ext_decl);
6175 if (TREE_CODE (ext_type) == FUNCTION_TYPE
6176 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
6177 TREE_TYPE (ext_type)))
6179 current_function_prototype_locus
6180 = DECL_SOURCE_LOCATION (ext_decl);
6181 current_function_prototype_built_in
6182 = C_DECL_BUILTIN_PROTOTYPE (ext_decl);
6183 current_function_prototype_arg_types
6184 = TYPE_ARG_TYPES (ext_type);
6190 /* Optionally warn of old-fashioned def with no previous prototype. */
6191 if (warn_strict_prototypes
6192 && old_decl != error_mark_node
6193 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0
6194 && C_DECL_ISNT_PROTOTYPE (old_decl))
6195 warning (OPT_Wstrict_prototypes,
6196 "function declaration isn%'t a prototype");
6197 /* Optionally warn of any global def with no previous prototype. */
6198 else if (warn_missing_prototypes
6199 && old_decl != error_mark_node
6200 && TREE_PUBLIC (decl1)
6201 && !MAIN_NAME_P (DECL_NAME (decl1))
6202 && C_DECL_ISNT_PROTOTYPE (old_decl))
6203 warning (OPT_Wmissing_prototypes, "no previous prototype for %q+D", decl1);
6204 /* Optionally warn of any def with no previous prototype
6205 if the function has already been used. */
6206 else if (warn_missing_prototypes
6208 && old_decl != error_mark_node
6209 && TREE_USED (old_decl)
6210 && TYPE_ARG_TYPES (TREE_TYPE (old_decl)) == 0)
6211 warning (OPT_Wmissing_prototypes,
6212 "%q+D was used with no prototype before its definition", decl1);
6213 /* Optionally warn of any global def with no previous declaration. */
6214 else if (warn_missing_declarations
6215 && TREE_PUBLIC (decl1)
6217 && !MAIN_NAME_P (DECL_NAME (decl1)))
6218 warning (OPT_Wmissing_declarations, "no previous declaration for %q+D",
6220 /* Optionally warn of any def with no previous declaration
6221 if the function has already been used. */
6222 else if (warn_missing_declarations
6224 && old_decl != error_mark_node
6225 && TREE_USED (old_decl)
6226 && C_DECL_IMPLICIT (old_decl))
6227 warning (OPT_Wmissing_declarations,
6228 "%q+D was used with no declaration before its definition", decl1);
6230 /* This function exists in static storage.
6231 (This does not mean `static' in the C sense!) */
6232 TREE_STATIC (decl1) = 1;
6234 /* A nested function is not global. */
6235 if (current_function_decl != 0)
6236 TREE_PUBLIC (decl1) = 0;
6238 /* This is the earliest point at which we might know the assembler
6239 name of the function. Thus, if it's set before this, die horribly. */
6240 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl1));
6242 /* If #pragma weak was used, mark the decl weak now. */
6243 if (current_scope == file_scope)
6244 maybe_apply_pragma_weak (decl1);
6246 /* Warn for unlikely, improbable, or stupid declarations of `main'. */
6247 if (warn_main > 0 && MAIN_NAME_P (DECL_NAME (decl1)))
6249 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
6250 != integer_type_node)
6251 pedwarn ("return type of %q+D is not %<int%>", decl1);
6253 check_main_parameter_types(decl1);
6255 if (!TREE_PUBLIC (decl1))
6256 pedwarn ("%q+D is normally a non-static function", decl1);
6259 /* Record the decl so that the function name is defined.
6260 If we already have a decl for this name, and it is a FUNCTION_DECL,
6261 use the old decl. */
6263 current_function_decl = pushdecl (decl1);
6266 declare_parm_level ();
6268 restype = TREE_TYPE (TREE_TYPE (current_function_decl));
6269 /* Promote the value to int before returning it. */
6270 if (c_promoting_integer_type_p (restype))
6272 /* It retains unsignedness if not really getting wider. */
6273 if (TYPE_UNSIGNED (restype)
6274 && (TYPE_PRECISION (restype)
6275 == TYPE_PRECISION (integer_type_node)))
6276 restype = unsigned_type_node;
6278 restype = integer_type_node;
6281 resdecl = build_decl (RESULT_DECL, NULL_TREE, restype);
6282 DECL_ARTIFICIAL (resdecl) = 1;
6283 DECL_IGNORED_P (resdecl) = 1;
6284 DECL_RESULT (current_function_decl) = resdecl;
6286 start_fname_decls ();
6291 /* Subroutine of store_parm_decls which handles new-style function
6292 definitions (prototype format). The parms already have decls, so we
6293 need only record them as in effect and complain if any redundant
6294 old-style parm decls were written. */
6296 store_parm_decls_newstyle (tree fndecl, const struct c_arg_info *arg_info)
6300 if (current_scope->bindings)
6302 error ("%Jold-style parameter declarations in prototyped "
6303 "function definition", fndecl);
6305 /* Get rid of the old-style declarations. */
6309 /* Don't issue this warning for nested functions, and don't issue this
6310 warning if we got here because ARG_INFO_TYPES was error_mark_node
6311 (this happens when a function definition has just an ellipsis in
6312 its parameter list). */
6313 else if (!in_system_header && !current_function_scope
6314 && arg_info->types != error_mark_node)
6315 warning (OPT_Wtraditional,
6316 "%Jtraditional C rejects ISO C style function definitions",
6319 /* Now make all the parameter declarations visible in the function body.
6320 We can bypass most of the grunt work of pushdecl. */
6321 for (decl = arg_info->parms; decl; decl = TREE_CHAIN (decl))
6323 DECL_CONTEXT (decl) = current_function_decl;
6324 if (DECL_NAME (decl))
6326 bind (DECL_NAME (decl), decl, current_scope,
6327 /*invisible=*/false, /*nested=*/false);
6328 if (!TREE_USED (decl))
6329 warn_if_shadowing (decl);
6332 error ("%Jparameter name omitted", decl);
6335 /* Record the parameter list in the function declaration. */
6336 DECL_ARGUMENTS (fndecl) = arg_info->parms;
6338 /* Now make all the ancillary declarations visible, likewise. */
6339 for (decl = arg_info->others; decl; decl = TREE_CHAIN (decl))
6341 DECL_CONTEXT (decl) = current_function_decl;
6342 if (DECL_NAME (decl))
6343 bind (DECL_NAME (decl), decl, current_scope,
6344 /*invisible=*/false, /*nested=*/false);
6347 /* And all the tag declarations. */
6348 for (decl = arg_info->tags; decl; decl = TREE_CHAIN (decl))
6349 if (TREE_PURPOSE (decl))
6350 bind (TREE_PURPOSE (decl), TREE_VALUE (decl), current_scope,
6351 /*invisible=*/false, /*nested=*/false);
6354 /* Subroutine of store_parm_decls which handles old-style function
6355 definitions (separate parameter list and declarations). */
6358 store_parm_decls_oldstyle (tree fndecl, const struct c_arg_info *arg_info)
6360 struct c_binding *b;
6361 tree parm, decl, last;
6362 tree parmids = arg_info->parms;
6363 struct pointer_set_t *seen_args = pointer_set_create ();
6365 if (!in_system_header)
6366 warning (OPT_Wold_style_definition, "%Jold-style function definition",
6369 /* Match each formal parameter name with its declaration. Save each
6370 decl in the appropriate TREE_PURPOSE slot of the parmids chain. */
6371 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6373 if (TREE_VALUE (parm) == 0)
6375 error ("%Jparameter name missing from parameter list", fndecl);
6376 TREE_PURPOSE (parm) = 0;
6380 b = I_SYMBOL_BINDING (TREE_VALUE (parm));
6381 if (b && B_IN_CURRENT_SCOPE (b))
6384 /* If we got something other than a PARM_DECL it is an error. */
6385 if (TREE_CODE (decl) != PARM_DECL)
6386 error ("%q+D declared as a non-parameter", decl);
6387 /* If the declaration is already marked, we have a duplicate
6388 name. Complain and ignore the duplicate. */
6389 else if (pointer_set_contains (seen_args, decl))
6391 error ("multiple parameters named %q+D", decl);
6392 TREE_PURPOSE (parm) = 0;
6395 /* If the declaration says "void", complain and turn it into
6397 else if (VOID_TYPE_P (TREE_TYPE (decl)))
6399 error ("parameter %q+D declared with void type", decl);
6400 TREE_TYPE (decl) = integer_type_node;
6401 DECL_ARG_TYPE (decl) = integer_type_node;
6402 layout_decl (decl, 0);
6404 warn_if_shadowing (decl);
6406 /* If no declaration found, default to int. */
6409 decl = build_decl (PARM_DECL, TREE_VALUE (parm), integer_type_node);
6410 DECL_ARG_TYPE (decl) = TREE_TYPE (decl);
6411 DECL_SOURCE_LOCATION (decl) = DECL_SOURCE_LOCATION (fndecl);
6413 warn_if_shadowing (decl);
6416 pedwarn ("type of %q+D defaults to %<int%>", decl);
6418 warning (OPT_Wmissing_parameter_type, "type of %q+D defaults to %<int%>", decl);
6421 TREE_PURPOSE (parm) = decl;
6422 pointer_set_insert (seen_args, decl);
6425 /* Now examine the parms chain for incomplete declarations
6426 and declarations with no corresponding names. */
6428 for (b = current_scope->bindings; b; b = b->prev)
6431 if (TREE_CODE (parm) != PARM_DECL)
6434 if (TREE_TYPE (parm) != error_mark_node
6435 && !COMPLETE_TYPE_P (TREE_TYPE (parm)))
6437 error ("parameter %q+D has incomplete type", parm);
6438 TREE_TYPE (parm) = error_mark_node;
6441 if (!pointer_set_contains (seen_args, parm))
6443 error ("declaration for parameter %q+D but no such parameter", parm);
6445 /* Pretend the parameter was not missing.
6446 This gets us to a standard state and minimizes
6447 further error messages. */
6448 parmids = chainon (parmids, tree_cons (parm, 0, 0));
6452 /* Chain the declarations together in the order of the list of
6453 names. Store that chain in the function decl, replacing the
6454 list of names. Update the current scope to match. */
6455 DECL_ARGUMENTS (fndecl) = 0;
6457 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6458 if (TREE_PURPOSE (parm))
6460 if (parm && TREE_PURPOSE (parm))
6462 last = TREE_PURPOSE (parm);
6463 DECL_ARGUMENTS (fndecl) = last;
6465 for (parm = TREE_CHAIN (parm); parm; parm = TREE_CHAIN (parm))
6466 if (TREE_PURPOSE (parm))
6468 TREE_CHAIN (last) = TREE_PURPOSE (parm);
6469 last = TREE_PURPOSE (parm);
6471 TREE_CHAIN (last) = 0;
6474 pointer_set_destroy (seen_args);
6476 /* If there was a previous prototype,
6477 set the DECL_ARG_TYPE of each argument according to
6478 the type previously specified, and report any mismatches. */
6480 if (current_function_prototype_arg_types)
6483 for (parm = DECL_ARGUMENTS (fndecl),
6484 type = current_function_prototype_arg_types;
6485 parm || (type && TREE_VALUE (type) != error_mark_node
6486 && (TYPE_MAIN_VARIANT (TREE_VALUE (type)) != void_type_node));
6487 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
6489 if (parm == 0 || type == 0
6490 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
6492 if (current_function_prototype_built_in)
6493 warning (0, "number of arguments doesn%'t match "
6494 "built-in prototype");
6497 error ("number of arguments doesn%'t match prototype");
6498 error ("%Hprototype declaration",
6499 ¤t_function_prototype_locus);
6503 /* Type for passing arg must be consistent with that
6504 declared for the arg. ISO C says we take the unqualified
6505 type for parameters declared with qualified type. */
6506 if (!comptypes (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (parm)),
6507 TYPE_MAIN_VARIANT (TREE_VALUE (type))))
6509 if (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
6510 == TYPE_MAIN_VARIANT (TREE_VALUE (type)))
6512 /* Adjust argument to match prototype. E.g. a previous
6513 `int foo(float);' prototype causes
6514 `int foo(x) float x; {...}' to be treated like
6515 `int foo(float x) {...}'. This is particularly
6516 useful for argument types like uid_t. */
6517 DECL_ARG_TYPE (parm) = TREE_TYPE (parm);
6519 if (targetm.calls.promote_prototypes (TREE_TYPE (current_function_decl))
6520 && INTEGRAL_TYPE_P (TREE_TYPE (parm))
6521 && TYPE_PRECISION (TREE_TYPE (parm))
6522 < TYPE_PRECISION (integer_type_node))
6523 DECL_ARG_TYPE (parm) = integer_type_node;
6527 /* ??? Is it possible to get here with a
6528 built-in prototype or will it always have
6529 been diagnosed as conflicting with an
6530 old-style definition and discarded? */
6531 if (current_function_prototype_built_in)
6532 warning (0, "promoted argument %qD "
6533 "doesn%'t match built-in prototype", parm);
6536 pedwarn ("promoted argument %qD "
6537 "doesn%'t match prototype", parm);
6538 pedwarn ("%Hprototype declaration",
6539 ¤t_function_prototype_locus);
6545 if (current_function_prototype_built_in)
6546 warning (0, "argument %qD doesn%'t match "
6547 "built-in prototype", parm);
6550 error ("argument %qD doesn%'t match prototype", parm);
6551 error ("%Hprototype declaration",
6552 ¤t_function_prototype_locus);
6557 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = 0;
6560 /* Otherwise, create a prototype that would match. */
6564 tree actual = 0, last = 0, type;
6566 for (parm = DECL_ARGUMENTS (fndecl); parm; parm = TREE_CHAIN (parm))
6568 type = tree_cons (NULL_TREE, DECL_ARG_TYPE (parm), NULL_TREE);
6570 TREE_CHAIN (last) = type;
6575 type = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
6577 TREE_CHAIN (last) = type;
6581 /* We are going to assign a new value for the TYPE_ACTUAL_ARG_TYPES
6582 of the type of this function, but we need to avoid having this
6583 affect the types of other similarly-typed functions, so we must
6584 first force the generation of an identical (but separate) type
6585 node for the relevant function type. The new node we create
6586 will be a variant of the main variant of the original function
6589 TREE_TYPE (fndecl) = build_variant_type_copy (TREE_TYPE (fndecl));
6591 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = actual;
6595 /* Store parameter declarations passed in ARG_INFO into the current
6596 function declaration. */
6599 store_parm_decls_from (struct c_arg_info *arg_info)
6601 current_function_arg_info = arg_info;
6602 store_parm_decls ();
6605 /* Store the parameter declarations into the current function declaration.
6606 This is called after parsing the parameter declarations, before
6607 digesting the body of the function.
6609 For an old-style definition, construct a prototype out of the old-style
6610 parameter declarations and inject it into the function's type. */
6613 store_parm_decls (void)
6615 tree fndecl = current_function_decl;
6618 /* The argument information block for FNDECL. */
6619 struct c_arg_info *arg_info = current_function_arg_info;
6620 current_function_arg_info = 0;
6622 /* True if this definition is written with a prototype. Note:
6623 despite C99 6.7.5.3p14, we can *not* treat an empty argument
6624 list in a function definition as equivalent to (void) -- an
6625 empty argument list specifies the function has no parameters,
6626 but only (void) sets up a prototype for future calls. */
6627 proto = arg_info->types != 0;
6630 store_parm_decls_newstyle (fndecl, arg_info);
6632 store_parm_decls_oldstyle (fndecl, arg_info);
6634 /* The next call to push_scope will be a function body. */
6636 next_is_function_body = true;
6638 /* Write a record describing this function definition to the prototypes
6639 file (if requested). */
6641 gen_aux_info_record (fndecl, 1, 0, proto);
6643 /* Initialize the RTL code for the function. */
6644 allocate_struct_function (fndecl);
6646 /* Begin the statement tree for this function. */
6647 DECL_SAVED_TREE (fndecl) = push_stmt_list ();
6649 /* ??? Insert the contents of the pending sizes list into the function
6650 to be evaluated. The only reason left to have this is
6651 void foo(int n, int array[n++])
6652 because we throw away the array type in favor of a pointer type, and
6653 thus won't naturally see the SAVE_EXPR containing the increment. All
6654 other pending sizes would be handled by gimplify_parameters. */
6657 for (t = nreverse (get_pending_sizes ()); t ; t = TREE_CHAIN (t))
6658 add_stmt (TREE_VALUE (t));
6661 /* Even though we're inside a function body, we still don't want to
6662 call expand_expr to calculate the size of a variable-sized array.
6663 We haven't necessarily assigned RTL to all variables yet, so it's
6664 not safe to try to expand expressions involving them. */
6665 cfun->x_dont_save_pending_sizes_p = 1;
6668 /* Emit diagnostics that require gimple input for detection. Operate on
6669 FNDECL and all its nested functions. */
6672 c_gimple_diagnostics_recursively (tree fndecl)
6674 struct cgraph_node *cgn;
6676 /* Handle attribute((warn_unused_result)). Relies on gimple input. */
6677 c_warn_unused_result (&DECL_SAVED_TREE (fndecl));
6679 /* Notice when OpenMP structured block constraints are violated. */
6681 diagnose_omp_structured_block_errors (fndecl);
6683 /* Finalize all nested functions now. */
6684 cgn = cgraph_node (fndecl);
6685 for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested)
6686 c_gimple_diagnostics_recursively (cgn->decl);
6689 /* Finish up a function declaration and compile that function
6690 all the way to assembler language output. The free the storage
6691 for the function definition.
6693 This is called after parsing the body of the function definition. */
6696 finish_function (void)
6698 tree fndecl = current_function_decl;
6700 label_context_stack_se = label_context_stack_se->next;
6701 label_context_stack_vm = label_context_stack_vm->next;
6703 if (TREE_CODE (fndecl) == FUNCTION_DECL
6704 && targetm.calls.promote_prototypes (TREE_TYPE (fndecl)))
6706 tree args = DECL_ARGUMENTS (fndecl);
6707 for (; args; args = TREE_CHAIN (args))
6709 tree type = TREE_TYPE (args);
6710 if (INTEGRAL_TYPE_P (type)
6711 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
6712 DECL_ARG_TYPE (args) = integer_type_node;
6716 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node)
6717 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
6719 /* Must mark the RESULT_DECL as being in this function. */
6721 if (DECL_RESULT (fndecl) && DECL_RESULT (fndecl) != error_mark_node)
6722 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
6724 if (MAIN_NAME_P (DECL_NAME (fndecl)) && flag_hosted)
6726 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (fndecl)))
6727 != integer_type_node)
6729 /* If warn_main is 1 (-Wmain) or 2 (-Wall), we have already warned.
6730 If warn_main is -1 (-Wno-main) we don't want to be warned. */
6732 pedwarn ("return type of %q+D is not %<int%>", fndecl);
6738 tree stmt = c_finish_return (integer_zero_node);
6739 #ifdef USE_MAPPED_LOCATION
6740 /* Hack. We don't want the middle-end to warn that this return
6741 is unreachable, so we mark its location as special. Using
6742 UNKNOWN_LOCATION has the problem that it gets clobbered in
6743 annotate_one_with_locus. A cleaner solution might be to
6744 ensure ! should_carry_locus_p (stmt), but that needs a flag.
6746 SET_EXPR_LOCATION (stmt, BUILTINS_LOCATION);
6748 /* Hack. We don't want the middle-end to warn that this
6749 return is unreachable, so put the statement on the
6751 annotate_with_file_line (stmt, input_filename, 0);
6757 /* Tie off the statement tree for this function. */
6758 DECL_SAVED_TREE (fndecl) = pop_stmt_list (DECL_SAVED_TREE (fndecl));
6760 finish_fname_decls ();
6762 /* Complain if there's just no return statement. */
6763 if (warn_return_type
6764 && TREE_CODE (TREE_TYPE (TREE_TYPE (fndecl))) != VOID_TYPE
6765 && !current_function_returns_value && !current_function_returns_null
6766 /* Don't complain if we are no-return. */
6767 && !current_function_returns_abnormally
6768 /* Don't warn for main(). */
6769 && !MAIN_NAME_P (DECL_NAME (fndecl))
6770 /* Or if they didn't actually specify a return type. */
6771 && !C_FUNCTION_IMPLICIT_INT (fndecl)
6772 /* Normally, with -Wreturn-type, flow will complain. Unless we're an
6773 inline function, as we might never be compiled separately. */
6774 && DECL_INLINE (fndecl))
6776 warning (OPT_Wreturn_type,
6777 "no return statement in function returning non-void");
6778 TREE_NO_WARNING (fndecl) = 1;
6781 /* With just -Wextra, complain only if function returns both with
6782 and without a value. */
6784 && current_function_returns_value
6785 && current_function_returns_null)
6786 warning (OPT_Wextra, "this function may return with or without a value");
6788 /* Store the end of the function, so that we get good line number
6789 info for the epilogue. */
6790 cfun->function_end_locus = input_location;
6792 /* If we don't have ctors/dtors sections, and this is a static
6793 constructor or destructor, it must be recorded now. */
6794 if (DECL_STATIC_CONSTRUCTOR (fndecl)
6795 && !targetm.have_ctors_dtors)
6796 static_ctors = tree_cons (NULL_TREE, fndecl, static_ctors);
6797 if (DECL_STATIC_DESTRUCTOR (fndecl)
6798 && !targetm.have_ctors_dtors)
6799 static_dtors = tree_cons (NULL_TREE, fndecl, static_dtors);
6801 /* Finalize the ELF visibility for the function. */
6802 c_determine_visibility (fndecl);
6804 /* Genericize before inlining. Delay genericizing nested functions
6805 until their parent function is genericized. Since finalizing
6806 requires GENERIC, delay that as well. */
6808 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node
6809 && !undef_nested_function)
6811 if (!decl_function_context (fndecl))
6813 c_genericize (fndecl);
6814 c_gimple_diagnostics_recursively (fndecl);
6816 /* ??? Objc emits functions after finalizing the compilation unit.
6817 This should be cleaned up later and this conditional removed. */
6818 if (cgraph_global_info_ready)
6820 c_expand_body (fndecl);
6824 cgraph_finalize_function (fndecl, false);
6828 /* Register this function with cgraph just far enough to get it
6829 added to our parent's nested function list. Handy, since the
6830 C front end doesn't have such a list. */
6831 (void) cgraph_node (fndecl);
6835 if (!decl_function_context (fndecl))
6836 undef_nested_function = false;
6838 /* We're leaving the context of this function, so zap cfun.
6839 It's still in DECL_STRUCT_FUNCTION, and we'll restore it in
6840 tree_rest_of_compilation. */
6842 current_function_decl = NULL;
6845 /* Generate the RTL for the body of FNDECL. */
6848 c_expand_body (tree fndecl)
6851 if (!DECL_INITIAL (fndecl)
6852 || DECL_INITIAL (fndecl) == error_mark_node)
6855 tree_rest_of_compilation (fndecl);
6857 if (DECL_STATIC_CONSTRUCTOR (fndecl)
6858 && targetm.have_ctors_dtors)
6859 targetm.asm_out.constructor (XEXP (DECL_RTL (fndecl), 0),
6860 DEFAULT_INIT_PRIORITY);
6861 if (DECL_STATIC_DESTRUCTOR (fndecl)
6862 && targetm.have_ctors_dtors)
6863 targetm.asm_out.destructor (XEXP (DECL_RTL (fndecl), 0),
6864 DEFAULT_INIT_PRIORITY);
6867 /* Check the declarations given in a for-loop for satisfying the C99
6868 constraints. If exactly one such decl is found, return it. */
6871 check_for_loop_decls (void)
6873 struct c_binding *b;
6874 tree one_decl = NULL_TREE;
6880 /* If we get here, declarations have been used in a for loop without
6881 the C99 for loop scope. This doesn't make much sense, so don't
6883 error ("%<for%> loop initial declaration used outside C99 mode");
6886 /* C99 subclause 6.8.5 paragraph 3:
6888 [#3] The declaration part of a for statement shall only
6889 declare identifiers for objects having storage class auto or
6892 It isn't clear whether, in this sentence, "identifiers" binds to
6893 "shall only declare" or to "objects" - that is, whether all identifiers
6894 declared must be identifiers for objects, or whether the restriction
6895 only applies to those that are. (A question on this in comp.std.c
6896 in November 2000 received no answer.) We implement the strictest
6897 interpretation, to avoid creating an extension which later causes
6900 for (b = current_scope->bindings; b; b = b->prev)
6903 tree decl = b->decl;
6908 switch (TREE_CODE (decl))
6911 if (TREE_STATIC (decl))
6912 error ("declaration of static variable %q+D in %<for%> loop "
6913 "initial declaration", decl);
6914 else if (DECL_EXTERNAL (decl))
6915 error ("declaration of %<extern%> variable %q+D in %<for%> loop "
6916 "initial declaration", decl);
6920 error ("%<struct %E%> declared in %<for%> loop initial declaration",
6924 error ("%<union %E%> declared in %<for%> loop initial declaration",
6928 error ("%<enum %E%> declared in %<for%> loop initial declaration",
6932 error ("declaration of non-variable %q+D in %<for%> loop "
6933 "initial declaration", decl);
6940 return n_decls == 1 ? one_decl : NULL_TREE;
6943 /* Save and reinitialize the variables
6944 used during compilation of a C function. */
6947 c_push_function_context (struct function *f)
6949 struct language_function *p;
6950 p = GGC_NEW (struct language_function);
6953 p->base.x_stmt_tree = c_stmt_tree;
6954 p->x_break_label = c_break_label;
6955 p->x_cont_label = c_cont_label;
6956 p->x_switch_stack = c_switch_stack;
6957 p->arg_info = current_function_arg_info;
6958 p->returns_value = current_function_returns_value;
6959 p->returns_null = current_function_returns_null;
6960 p->returns_abnormally = current_function_returns_abnormally;
6961 p->warn_about_return_type = warn_about_return_type;
6964 /* Restore the variables used during compilation of a C function. */
6967 c_pop_function_context (struct function *f)
6969 struct language_function *p = f->language;
6971 if (DECL_STRUCT_FUNCTION (current_function_decl) == 0
6972 && DECL_SAVED_TREE (current_function_decl) == NULL_TREE)
6974 /* Stop pointing to the local nodes about to be freed. */
6975 /* But DECL_INITIAL must remain nonzero so we know this
6976 was an actual function definition. */
6977 DECL_INITIAL (current_function_decl) = error_mark_node;
6978 DECL_ARGUMENTS (current_function_decl) = 0;
6981 c_stmt_tree = p->base.x_stmt_tree;
6982 c_break_label = p->x_break_label;
6983 c_cont_label = p->x_cont_label;
6984 c_switch_stack = p->x_switch_stack;
6985 current_function_arg_info = p->arg_info;
6986 current_function_returns_value = p->returns_value;
6987 current_function_returns_null = p->returns_null;
6988 current_function_returns_abnormally = p->returns_abnormally;
6989 warn_about_return_type = p->warn_about_return_type;
6994 /* Copy the DECL_LANG_SPECIFIC data associated with DECL. */
6997 c_dup_lang_specific_decl (tree decl)
6999 struct lang_decl *ld;
7001 if (!DECL_LANG_SPECIFIC (decl))
7004 ld = GGC_NEW (struct lang_decl);
7005 memcpy (ld, DECL_LANG_SPECIFIC (decl), sizeof (struct lang_decl));
7006 DECL_LANG_SPECIFIC (decl) = ld;
7009 /* The functions below are required for functionality of doing
7010 function at once processing in the C front end. Currently these
7011 functions are not called from anywhere in the C front end, but as
7012 these changes continue, that will change. */
7014 /* Returns the stmt_tree (if any) to which statements are currently
7015 being added. If there is no active statement-tree, NULL is
7019 current_stmt_tree (void)
7021 return &c_stmt_tree;
7024 /* Nonzero if TYPE is an anonymous union or struct type. Always 0 in
7028 anon_aggr_type_p (tree ARG_UNUSED (node))
7033 /* Return the global value of T as a symbol. */
7036 identifier_global_value (tree t)
7038 struct c_binding *b;
7040 for (b = I_SYMBOL_BINDING (t); b; b = b->shadowed)
7041 if (B_IN_FILE_SCOPE (b) || B_IN_EXTERNAL_SCOPE (b))
7047 /* Record a builtin type for C. If NAME is non-NULL, it is the name used;
7048 otherwise the name is found in ridpointers from RID_INDEX. */
7051 record_builtin_type (enum rid rid_index, const char *name, tree type)
7055 id = ridpointers[(int) rid_index];
7057 id = get_identifier (name);
7058 decl = build_decl (TYPE_DECL, id, type);
7060 if (debug_hooks->type_decl)
7061 debug_hooks->type_decl (decl, false);
7064 /* Build the void_list_node (void_type_node having been created). */
7066 build_void_list_node (void)
7068 tree t = build_tree_list (NULL_TREE, void_type_node);
7072 /* Return a c_parm structure with the given SPECS, ATTRS and DECLARATOR. */
7075 build_c_parm (struct c_declspecs *specs, tree attrs,
7076 struct c_declarator *declarator)
7078 struct c_parm *ret = XOBNEW (&parser_obstack, struct c_parm);
7081 ret->declarator = declarator;
7085 /* Return a declarator with nested attributes. TARGET is the inner
7086 declarator to which these attributes apply. ATTRS are the
7089 struct c_declarator *
7090 build_attrs_declarator (tree attrs, struct c_declarator *target)
7092 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7093 ret->kind = cdk_attrs;
7094 ret->declarator = target;
7095 ret->u.attrs = attrs;
7099 /* Return a declarator for a function with arguments specified by ARGS
7100 and return type specified by TARGET. */
7102 struct c_declarator *
7103 build_function_declarator (struct c_arg_info *args,
7104 struct c_declarator *target)
7106 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7107 ret->kind = cdk_function;
7108 ret->declarator = target;
7109 ret->u.arg_info = args;
7113 /* Return a declarator for the identifier IDENT (which may be
7114 NULL_TREE for an abstract declarator). */
7116 struct c_declarator *
7117 build_id_declarator (tree ident)
7119 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7121 ret->declarator = 0;
7123 /* Default value - may get reset to a more precise location. */
7124 ret->id_loc = input_location;
7128 /* Return something to represent absolute declarators containing a *.
7129 TARGET is the absolute declarator that the * contains.
7130 TYPE_QUALS_ATTRS is a structure for type qualifiers and attributes
7131 to apply to the pointer type. */
7133 struct c_declarator *
7134 make_pointer_declarator (struct c_declspecs *type_quals_attrs,
7135 struct c_declarator *target)
7139 struct c_declarator *itarget = target;
7140 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7141 if (type_quals_attrs)
7143 attrs = type_quals_attrs->attrs;
7144 quals = quals_from_declspecs (type_quals_attrs);
7145 if (attrs != NULL_TREE)
7146 itarget = build_attrs_declarator (attrs, target);
7148 ret->kind = cdk_pointer;
7149 ret->declarator = itarget;
7150 ret->u.pointer_quals = quals;
7154 /* Return a pointer to a structure for an empty list of declaration
7157 struct c_declspecs *
7158 build_null_declspecs (void)
7160 struct c_declspecs *ret = XOBNEW (&parser_obstack, struct c_declspecs);
7164 ret->typespec_word = cts_none;
7165 ret->storage_class = csc_none;
7166 ret->declspecs_seen_p = false;
7167 ret->type_seen_p = false;
7168 ret->non_sc_seen_p = false;
7169 ret->typedef_p = false;
7170 ret->tag_defined_p = false;
7171 ret->explicit_signed_p = false;
7172 ret->deprecated_p = false;
7173 ret->default_int_p = false;
7174 ret->long_p = false;
7175 ret->long_long_p = false;
7176 ret->short_p = false;
7177 ret->signed_p = false;
7178 ret->unsigned_p = false;
7179 ret->complex_p = false;
7180 ret->inline_p = false;
7181 ret->thread_p = false;
7182 ret->const_p = false;
7183 ret->volatile_p = false;
7184 ret->restrict_p = false;
7188 /* Add the type qualifier QUAL to the declaration specifiers SPECS,
7191 struct c_declspecs *
7192 declspecs_add_qual (struct c_declspecs *specs, tree qual)
7196 specs->non_sc_seen_p = true;
7197 specs->declspecs_seen_p = true;
7198 gcc_assert (TREE_CODE (qual) == IDENTIFIER_NODE
7199 && C_IS_RESERVED_WORD (qual));
7200 i = C_RID_CODE (qual);
7204 dupe = specs->const_p;
7205 specs->const_p = true;
7208 dupe = specs->volatile_p;
7209 specs->volatile_p = true;
7212 dupe = specs->restrict_p;
7213 specs->restrict_p = true;
7218 if (dupe && pedantic && !flag_isoc99)
7219 pedwarn ("duplicate %qE", qual);
7223 /* Add the type specifier TYPE to the declaration specifiers SPECS,
7226 struct c_declspecs *
7227 declspecs_add_type (struct c_declspecs *specs, struct c_typespec spec)
7229 tree type = spec.spec;
7230 specs->non_sc_seen_p = true;
7231 specs->declspecs_seen_p = true;
7232 specs->type_seen_p = true;
7233 if (TREE_DEPRECATED (type))
7234 specs->deprecated_p = true;
7236 /* Handle type specifier keywords. */
7237 if (TREE_CODE (type) == IDENTIFIER_NODE && C_IS_RESERVED_WORD (type))
7239 enum rid i = C_RID_CODE (type);
7242 error ("two or more data types in declaration specifiers");
7245 if ((int) i <= (int) RID_LAST_MODIFIER)
7247 /* "long", "short", "signed", "unsigned" or "_Complex". */
7252 if (specs->long_long_p)
7254 error ("%<long long long%> is too long for GCC");
7259 if (specs->typespec_word == cts_double)
7261 error ("both %<long long%> and %<double%> in "
7262 "declaration specifiers");
7265 if (pedantic && !flag_isoc99 && !in_system_header
7267 pedwarn ("ISO C90 does not support %<long long%>");
7268 specs->long_long_p = 1;
7272 error ("both %<long%> and %<short%> in "
7273 "declaration specifiers");
7274 else if (specs->typespec_word == cts_void)
7275 error ("both %<long%> and %<void%> in "
7276 "declaration specifiers");
7277 else if (specs->typespec_word == cts_bool)
7278 error ("both %<long%> and %<_Bool%> in "
7279 "declaration specifiers");
7280 else if (specs->typespec_word == cts_char)
7281 error ("both %<long%> and %<char%> in "
7282 "declaration specifiers");
7283 else if (specs->typespec_word == cts_float)
7284 error ("both %<long%> and %<float%> in "
7285 "declaration specifiers");
7286 else if (specs->typespec_word == cts_dfloat32)
7287 error ("both %<long%> and %<_Decimal32%> in "
7288 "declaration specifiers");
7289 else if (specs->typespec_word == cts_dfloat64)
7290 error ("both %<long%> and %<_Decimal64%> in "
7291 "declaration specifiers");
7292 else if (specs->typespec_word == cts_dfloat128)
7293 error ("both %<long%> and %<_Decimal128%> in "
7294 "declaration specifiers");
7296 specs->long_p = true;
7299 dupe = specs->short_p;
7301 error ("both %<long%> and %<short%> in "
7302 "declaration specifiers");
7303 else if (specs->typespec_word == cts_void)
7304 error ("both %<short%> and %<void%> in "
7305 "declaration specifiers");
7306 else if (specs->typespec_word == cts_bool)
7307 error ("both %<short%> and %<_Bool%> in "
7308 "declaration specifiers");
7309 else if (specs->typespec_word == cts_char)
7310 error ("both %<short%> and %<char%> in "
7311 "declaration specifiers");
7312 else if (specs->typespec_word == cts_float)
7313 error ("both %<short%> and %<float%> in "
7314 "declaration specifiers");
7315 else if (specs->typespec_word == cts_double)
7316 error ("both %<short%> and %<double%> in "
7317 "declaration specifiers");
7318 else if (specs->typespec_word == cts_dfloat32)
7319 error ("both %<short%> and %<_Decimal32%> in "
7320 "declaration specifiers");
7321 else if (specs->typespec_word == cts_dfloat64)
7322 error ("both %<short%> and %<_Decimal64%> in "
7323 "declaration specifiers");
7324 else if (specs->typespec_word == cts_dfloat128)
7325 error ("both %<short%> and %<_Decimal128%> in "
7326 "declaration specifiers");
7328 specs->short_p = true;
7331 dupe = specs->signed_p;
7332 if (specs->unsigned_p)
7333 error ("both %<signed%> and %<unsigned%> in "
7334 "declaration specifiers");
7335 else if (specs->typespec_word == cts_void)
7336 error ("both %<signed%> and %<void%> in "
7337 "declaration specifiers");
7338 else if (specs->typespec_word == cts_bool)
7339 error ("both %<signed%> and %<_Bool%> in "
7340 "declaration specifiers");
7341 else if (specs->typespec_word == cts_float)
7342 error ("both %<signed%> and %<float%> in "
7343 "declaration specifiers");
7344 else if (specs->typespec_word == cts_double)
7345 error ("both %<signed%> and %<double%> in "
7346 "declaration specifiers");
7347 else if (specs->typespec_word == cts_dfloat32)
7348 error ("both %<signed%> and %<_Decimal32%> in "
7349 "declaration specifiers");
7350 else if (specs->typespec_word == cts_dfloat64)
7351 error ("both %<signed%> and %<_Decimal64%> in "
7352 "declaration specifiers");
7353 else if (specs->typespec_word == cts_dfloat128)
7354 error ("both %<signed%> and %<_Decimal128%> in "
7355 "declaration specifiers");
7357 specs->signed_p = true;
7360 dupe = specs->unsigned_p;
7361 if (specs->signed_p)
7362 error ("both %<signed%> and %<unsigned%> in "
7363 "declaration specifiers");
7364 else if (specs->typespec_word == cts_void)
7365 error ("both %<unsigned%> and %<void%> in "
7366 "declaration specifiers");
7367 else if (specs->typespec_word == cts_bool)
7368 error ("both %<unsigned%> and %<_Bool%> in "
7369 "declaration specifiers");
7370 else if (specs->typespec_word == cts_float)
7371 error ("both %<unsigned%> and %<float%> in "
7372 "declaration specifiers");
7373 else if (specs->typespec_word == cts_double)
7374 error ("both %<unsigned%> and %<double%> in "
7375 "declaration specifiers");
7376 else if (specs->typespec_word == cts_dfloat32)
7377 error ("both %<unsigned%> and %<_Decimal32%> in "
7378 "declaration specifiers");
7379 else if (specs->typespec_word == cts_dfloat64)
7380 error ("both %<unsigned%> and %<_Decimal64%> in "
7381 "declaration specifiers");
7382 else if (specs->typespec_word == cts_dfloat128)
7383 error ("both %<unsigned%> and %<_Decimal128%> in "
7384 "declaration specifiers");
7386 specs->unsigned_p = true;
7389 dupe = specs->complex_p;
7390 if (pedantic && !flag_isoc99 && !in_system_header)
7391 pedwarn ("ISO C90 does not support complex types");
7392 if (specs->typespec_word == cts_void)
7393 error ("both %<complex%> and %<void%> in "
7394 "declaration specifiers");
7395 else if (specs->typespec_word == cts_bool)
7396 error ("both %<complex%> and %<_Bool%> in "
7397 "declaration specifiers");
7398 else if (specs->typespec_word == cts_dfloat32)
7399 error ("both %<complex%> and %<_Decimal32%> in "
7400 "declaration specifiers");
7401 else if (specs->typespec_word == cts_dfloat64)
7402 error ("both %<complex%> and %<_Decimal64%> in "
7403 "declaration specifiers");
7404 else if (specs->typespec_word == cts_dfloat128)
7405 error ("both %<complex%> and %<_Decimal128%> in "
7406 "declaration specifiers");
7408 specs->complex_p = true;
7415 error ("duplicate %qE", type);
7421 /* "void", "_Bool", "char", "int", "float" or "double". */
7422 if (specs->typespec_word != cts_none)
7424 error ("two or more data types in declaration specifiers");
7431 error ("both %<long%> and %<void%> in "
7432 "declaration specifiers");
7433 else if (specs->short_p)
7434 error ("both %<short%> and %<void%> in "
7435 "declaration specifiers");
7436 else if (specs->signed_p)
7437 error ("both %<signed%> and %<void%> in "
7438 "declaration specifiers");
7439 else if (specs->unsigned_p)
7440 error ("both %<unsigned%> and %<void%> in "
7441 "declaration specifiers");
7442 else if (specs->complex_p)
7443 error ("both %<complex%> and %<void%> in "
7444 "declaration specifiers");
7446 specs->typespec_word = cts_void;
7450 error ("both %<long%> and %<_Bool%> in "
7451 "declaration specifiers");
7452 else if (specs->short_p)
7453 error ("both %<short%> and %<_Bool%> in "
7454 "declaration specifiers");
7455 else if (specs->signed_p)
7456 error ("both %<signed%> and %<_Bool%> in "
7457 "declaration specifiers");
7458 else if (specs->unsigned_p)
7459 error ("both %<unsigned%> and %<_Bool%> in "
7460 "declaration specifiers");
7461 else if (specs->complex_p)
7462 error ("both %<complex%> and %<_Bool%> in "
7463 "declaration specifiers");
7465 specs->typespec_word = cts_bool;
7469 error ("both %<long%> and %<char%> in "
7470 "declaration specifiers");
7471 else if (specs->short_p)
7472 error ("both %<short%> and %<char%> in "
7473 "declaration specifiers");
7475 specs->typespec_word = cts_char;
7478 specs->typespec_word = cts_int;
7482 error ("both %<long%> and %<float%> in "
7483 "declaration specifiers");
7484 else if (specs->short_p)
7485 error ("both %<short%> and %<float%> in "
7486 "declaration specifiers");
7487 else if (specs->signed_p)
7488 error ("both %<signed%> and %<float%> in "
7489 "declaration specifiers");
7490 else if (specs->unsigned_p)
7491 error ("both %<unsigned%> and %<float%> in "
7492 "declaration specifiers");
7494 specs->typespec_word = cts_float;
7497 if (specs->long_long_p)
7498 error ("both %<long long%> and %<double%> in "
7499 "declaration specifiers");
7500 else if (specs->short_p)
7501 error ("both %<short%> and %<double%> in "
7502 "declaration specifiers");
7503 else if (specs->signed_p)
7504 error ("both %<signed%> and %<double%> in "
7505 "declaration specifiers");
7506 else if (specs->unsigned_p)
7507 error ("both %<unsigned%> and %<double%> in "
7508 "declaration specifiers");
7510 specs->typespec_word = cts_double;
7517 if (i == RID_DFLOAT32)
7519 else if (i == RID_DFLOAT64)
7522 str = "_Decimal128";
7523 if (specs->long_long_p)
7524 error ("both %<long long%> and %<%s%> in "
7525 "declaration specifiers", str);
7527 error ("both %<long%> and %<%s%> in "
7528 "declaration specifiers", str);
7529 else if (specs->short_p)
7530 error ("both %<short%> and %<%s%> in "
7531 "declaration specifiers", str);
7532 else if (specs->signed_p)
7533 error ("both %<signed%> and %<%s%> in "
7534 "declaration specifiers", str);
7535 else if (specs->unsigned_p)
7536 error ("both %<unsigned%> and %<%s%> in "
7537 "declaration specifiers", str);
7538 else if (specs->complex_p)
7539 error ("both %<complex%> and %<%s%> in "
7540 "declaration specifiers", str);
7541 else if (i == RID_DFLOAT32)
7542 specs->typespec_word = cts_dfloat32;
7543 else if (i == RID_DFLOAT64)
7544 specs->typespec_word = cts_dfloat64;
7546 specs->typespec_word = cts_dfloat128;
7548 if (!targetm.decimal_float_supported_p ())
7549 error ("decimal floating point not supported for this target");
7551 pedwarn ("ISO C does not support decimal floating point");
7554 /* ObjC reserved word "id", handled below. */
7560 /* Now we have a typedef (a TYPE_DECL node), an identifier (some
7561 form of ObjC type, cases such as "int" and "long" being handled
7562 above), a TYPE (struct, union, enum and typeof specifiers) or an
7563 ERROR_MARK. In none of these cases may there have previously
7564 been any type specifiers. */
7565 if (specs->type || specs->typespec_word != cts_none
7566 || specs->long_p || specs->short_p || specs->signed_p
7567 || specs->unsigned_p || specs->complex_p)
7568 error ("two or more data types in declaration specifiers");
7569 else if (TREE_CODE (type) == TYPE_DECL)
7571 if (TREE_TYPE (type) == error_mark_node)
7572 ; /* Allow the type to default to int to avoid cascading errors. */
7575 specs->type = TREE_TYPE (type);
7576 specs->decl_attr = DECL_ATTRIBUTES (type);
7577 specs->typedef_p = true;
7578 specs->explicit_signed_p = C_TYPEDEF_EXPLICITLY_SIGNED (type);
7581 else if (TREE_CODE (type) == IDENTIFIER_NODE)
7583 tree t = lookup_name (type);
7584 if (!t || TREE_CODE (t) != TYPE_DECL)
7585 error ("%qE fails to be a typedef or built in type", type);
7586 else if (TREE_TYPE (t) == error_mark_node)
7589 specs->type = TREE_TYPE (t);
7591 else if (TREE_CODE (type) != ERROR_MARK)
7593 if (spec.kind == ctsk_tagdef || spec.kind == ctsk_tagfirstref)
7594 specs->tag_defined_p = true;
7595 if (spec.kind == ctsk_typeof)
7596 specs->typedef_p = true;
7603 /* Add the storage class specifier or function specifier SCSPEC to the
7604 declaration specifiers SPECS, returning SPECS. */
7606 struct c_declspecs *
7607 declspecs_add_scspec (struct c_declspecs *specs, tree scspec)
7610 enum c_storage_class n = csc_none;
7612 specs->declspecs_seen_p = true;
7613 gcc_assert (TREE_CODE (scspec) == IDENTIFIER_NODE
7614 && C_IS_RESERVED_WORD (scspec));
7615 i = C_RID_CODE (scspec);
7616 if (specs->non_sc_seen_p)
7617 warning (OPT_Wold_style_declaration,
7618 "%qE is not at beginning of declaration", scspec);
7622 /* C99 permits duplicate inline. Although of doubtful utility,
7623 it seems simplest to permit it in gnu89 mode as well, as
7624 there is also little utility in maintaining this as a
7625 difference between gnu89 and C99 inline. */
7627 specs->inline_p = true;
7630 dupe = specs->thread_p;
7631 if (specs->storage_class == csc_auto)
7632 error ("%<__thread%> used with %<auto%>");
7633 else if (specs->storage_class == csc_register)
7634 error ("%<__thread%> used with %<register%>");
7635 else if (specs->storage_class == csc_typedef)
7636 error ("%<__thread%> used with %<typedef%>");
7638 specs->thread_p = true;
7645 /* Diagnose "__thread extern". */
7646 if (specs->thread_p)
7647 error ("%<__thread%> before %<extern%>");
7654 /* Diagnose "__thread static". */
7655 if (specs->thread_p)
7656 error ("%<__thread%> before %<static%>");
7664 if (n != csc_none && n == specs->storage_class)
7667 error ("duplicate %qE", scspec);
7670 if (specs->storage_class != csc_none && n != specs->storage_class)
7672 error ("multiple storage classes in declaration specifiers");
7676 specs->storage_class = n;
7677 if (n != csc_extern && n != csc_static && specs->thread_p)
7679 error ("%<__thread%> used with %qE", scspec);
7680 specs->thread_p = false;
7687 /* Add the attributes ATTRS to the declaration specifiers SPECS,
7690 struct c_declspecs *
7691 declspecs_add_attrs (struct c_declspecs *specs, tree attrs)
7693 specs->attrs = chainon (attrs, specs->attrs);
7694 specs->declspecs_seen_p = true;
7698 /* Combine "long", "short", "signed", "unsigned" and "_Complex" type
7699 specifiers with any other type specifier to determine the resulting
7700 type. This is where ISO C checks on complex types are made, since
7701 "_Complex long" is a prefix of the valid ISO C type "_Complex long
7704 struct c_declspecs *
7705 finish_declspecs (struct c_declspecs *specs)
7707 /* If a type was specified as a whole, we have no modifiers and are
7709 if (specs->type != NULL_TREE)
7711 gcc_assert (!specs->long_p && !specs->long_long_p && !specs->short_p
7712 && !specs->signed_p && !specs->unsigned_p
7713 && !specs->complex_p);
7717 /* If none of "void", "_Bool", "char", "int", "float" or "double"
7718 has been specified, treat it as "int" unless "_Complex" is
7719 present and there are no other specifiers. If we just have
7720 "_Complex", it is equivalent to "_Complex double", but e.g.
7721 "_Complex short" is equivalent to "_Complex short int". */
7722 if (specs->typespec_word == cts_none)
7724 if (specs->long_p || specs->short_p
7725 || specs->signed_p || specs->unsigned_p)
7727 specs->typespec_word = cts_int;
7729 else if (specs->complex_p)
7731 specs->typespec_word = cts_double;
7733 pedwarn ("ISO C does not support plain %<complex%> meaning "
7734 "%<double complex%>");
7738 specs->typespec_word = cts_int;
7739 specs->default_int_p = true;
7740 /* We don't diagnose this here because grokdeclarator will
7741 give more specific diagnostics according to whether it is
7742 a function definition. */
7746 /* If "signed" was specified, record this to distinguish "int" and
7747 "signed int" in the case of a bit-field with
7748 -funsigned-bitfields. */
7749 specs->explicit_signed_p = specs->signed_p;
7751 /* Now compute the actual type. */
7752 switch (specs->typespec_word)
7755 gcc_assert (!specs->long_p && !specs->short_p
7756 && !specs->signed_p && !specs->unsigned_p
7757 && !specs->complex_p);
7758 specs->type = void_type_node;
7761 gcc_assert (!specs->long_p && !specs->short_p
7762 && !specs->signed_p && !specs->unsigned_p
7763 && !specs->complex_p);
7764 specs->type = boolean_type_node;
7767 gcc_assert (!specs->long_p && !specs->short_p);
7768 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7769 if (specs->signed_p)
7770 specs->type = signed_char_type_node;
7771 else if (specs->unsigned_p)
7772 specs->type = unsigned_char_type_node;
7774 specs->type = char_type_node;
7775 if (specs->complex_p)
7778 pedwarn ("ISO C does not support complex integer types");
7779 specs->type = build_complex_type (specs->type);
7783 gcc_assert (!(specs->long_p && specs->short_p));
7784 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7785 if (specs->long_long_p)
7786 specs->type = (specs->unsigned_p
7787 ? long_long_unsigned_type_node
7788 : long_long_integer_type_node);
7789 else if (specs->long_p)
7790 specs->type = (specs->unsigned_p
7791 ? long_unsigned_type_node
7792 : long_integer_type_node);
7793 else if (specs->short_p)
7794 specs->type = (specs->unsigned_p
7795 ? short_unsigned_type_node
7796 : short_integer_type_node);
7798 specs->type = (specs->unsigned_p
7799 ? unsigned_type_node
7800 : integer_type_node);
7801 if (specs->complex_p)
7804 pedwarn ("ISO C does not support complex integer types");
7805 specs->type = build_complex_type (specs->type);
7809 gcc_assert (!specs->long_p && !specs->short_p
7810 && !specs->signed_p && !specs->unsigned_p);
7811 specs->type = (specs->complex_p
7812 ? complex_float_type_node
7816 gcc_assert (!specs->long_long_p && !specs->short_p
7817 && !specs->signed_p && !specs->unsigned_p);
7820 specs->type = (specs->complex_p
7821 ? complex_long_double_type_node
7822 : long_double_type_node);
7826 specs->type = (specs->complex_p
7827 ? complex_double_type_node
7828 : double_type_node);
7834 gcc_assert (!specs->long_p && !specs->long_long_p && !specs->short_p
7835 && !specs->signed_p && !specs->unsigned_p && !specs->complex_p);
7836 if (specs->typespec_word == cts_dfloat32)
7837 specs->type = dfloat32_type_node;
7838 else if (specs->typespec_word == cts_dfloat64)
7839 specs->type = dfloat64_type_node;
7841 specs->type = dfloat128_type_node;
7850 /* Synthesize a function which calls all the global ctors or global
7851 dtors in this file. This is only used for targets which do not
7852 support .ctors/.dtors sections. FIXME: Migrate into cgraph. */
7854 build_cdtor (int method_type, tree cdtors)
7861 for (; cdtors; cdtors = TREE_CHAIN (cdtors))
7862 append_to_statement_list (build_function_call (TREE_VALUE (cdtors), 0),
7865 cgraph_build_static_cdtor (method_type, body, DEFAULT_INIT_PRIORITY);
7868 /* A subroutine of c_write_global_declarations. Perform final processing
7869 on one file scope's declarations (or the external scope's declarations),
7873 c_write_global_declarations_1 (tree globals)
7878 /* Process the decls in the order they were written. */
7879 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7881 /* Check for used but undefined static functions using the C
7882 standard's definition of "used", and set TREE_NO_WARNING so
7883 that check_global_declarations doesn't repeat the check. */
7884 if (TREE_CODE (decl) == FUNCTION_DECL
7885 && DECL_INITIAL (decl) == 0
7886 && DECL_EXTERNAL (decl)
7887 && !TREE_PUBLIC (decl)
7888 && C_DECL_USED (decl))
7890 pedwarn ("%q+F used but never defined", decl);
7891 TREE_NO_WARNING (decl) = 1;
7894 wrapup_global_declaration_1 (decl);
7900 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7901 reconsider |= wrapup_global_declaration_2 (decl);
7905 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7906 check_global_declaration_1 (decl);
7909 /* A subroutine of c_write_global_declarations Emit debug information for each
7910 of the declarations in GLOBALS. */
7913 c_write_global_declarations_2 (tree globals)
7917 for (decl = globals; decl ; decl = TREE_CHAIN (decl))
7918 debug_hooks->global_decl (decl);
7921 /* Preserve the external declarations scope across a garbage collect. */
7922 static GTY(()) tree ext_block;
7925 c_write_global_declarations (void)
7929 /* We don't want to do this if generating a PCH. */
7933 /* Don't waste time on further processing if -fsyntax-only or we've
7934 encountered errors. */
7935 if (flag_syntax_only || errorcount || sorrycount || cpp_errors (parse_in))
7938 /* Close the external scope. */
7939 ext_block = pop_scope ();
7941 gcc_assert (!current_scope);
7945 tree tmp = BLOCK_VARS (ext_block);
7947 FILE * stream = dump_begin (TDI_tu, &flags);
7950 dump_node (tmp, flags & ~TDF_SLIM, stream);
7951 dump_end (TDI_tu, stream);
7955 /* Process all file scopes in this compilation, and the external_scope,
7956 through wrapup_global_declarations and check_global_declarations. */
7957 for (t = all_translation_units; t; t = TREE_CHAIN (t))
7958 c_write_global_declarations_1 (BLOCK_VARS (DECL_INITIAL (t)));
7959 c_write_global_declarations_1 (BLOCK_VARS (ext_block));
7961 /* Generate functions to call static constructors and destructors
7962 for targets that do not support .ctors/.dtors sections. These
7963 functions have magic names which are detected by collect2. */
7964 build_cdtor ('I', static_ctors); static_ctors = 0;
7965 build_cdtor ('D', static_dtors); static_dtors = 0;
7967 /* We're done parsing; proceed to optimize and emit assembly.
7968 FIXME: shouldn't be the front end's responsibility to call this. */
7971 /* After cgraph has had a chance to emit everything that's going to
7972 be emitted, output debug information for globals. */
7973 if (errorcount == 0 && sorrycount == 0)
7975 timevar_push (TV_SYMOUT);
7976 for (t = all_translation_units; t; t = TREE_CHAIN (t))
7977 c_write_global_declarations_2 (BLOCK_VARS (DECL_INITIAL (t)));
7978 c_write_global_declarations_2 (BLOCK_VARS (ext_block));
7979 timevar_pop (TV_SYMOUT);
7985 #include "gt-c-decl.h"