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, 2006, 2007, 2008
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
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"
56 #include "tree-iterator.h"
57 #include "diagnostic.h"
58 #include "tree-dump.h"
63 #include "langhooks-def.h"
64 #include "pointer-set.h"
67 /* In grokdeclarator, distinguish syntactic contexts of declarators. */
69 { NORMAL, /* Ordinary declaration */
70 FUNCDEF, /* Function definition */
71 PARM, /* Declaration of parm before function body */
72 FIELD, /* Declaration inside struct or union */
73 TYPENAME}; /* Typename (inside cast or sizeof) */
75 /* States indicating how grokdeclarator() should handle declspecs marked
76 with __attribute__((deprecated)). An object declared as
77 __attribute__((deprecated)) suppresses warnings of uses of other
80 enum deprecated_states {
86 /* Nonzero if we have seen an invalid cross reference
87 to a struct, union, or enum, but not yet printed the message. */
88 tree pending_invalid_xref;
90 /* File and line to appear in the eventual error message. */
91 location_t pending_invalid_xref_location;
93 /* True means we've initialized exception handling. */
94 bool c_eh_initialized_p;
96 /* The file and line that the prototype came from if this is an
97 old-style definition; used for diagnostics in
98 store_parm_decls_oldstyle. */
100 static location_t current_function_prototype_locus;
102 /* Whether this prototype was built-in. */
104 static bool current_function_prototype_built_in;
106 /* The argument type information of this prototype. */
108 static tree current_function_prototype_arg_types;
110 /* The argument information structure for the function currently being
113 static struct c_arg_info *current_function_arg_info;
115 /* The obstack on which parser and related data structures, which are
116 not live beyond their top-level declaration or definition, are
118 struct obstack parser_obstack;
120 /* The current statement tree. */
122 static GTY(()) struct stmt_tree_s c_stmt_tree;
124 /* State saving variables. */
128 /* Linked list of TRANSLATION_UNIT_DECLS for the translation units
129 included in this invocation. Note that the current translation
130 unit is not included in this list. */
132 static GTY(()) tree all_translation_units;
134 /* A list of decls to be made automatically visible in each file scope. */
135 static GTY(()) tree visible_builtins;
137 /* Set to 0 at beginning of a function definition, set to 1 if
138 a return statement that specifies a return value is seen. */
140 int current_function_returns_value;
142 /* Set to 0 at beginning of a function definition, set to 1 if
143 a return statement with no argument is seen. */
145 int current_function_returns_null;
147 /* Set to 0 at beginning of a function definition, set to 1 if
148 a call to a noreturn function is seen. */
150 int current_function_returns_abnormally;
152 /* Set to nonzero by `grokdeclarator' for a function
153 whose return type is defaulted, if warnings for this are desired. */
155 static int warn_about_return_type;
157 /* Nonzero when the current toplevel function contains a declaration
158 of a nested function which is never defined. */
160 static bool undef_nested_function;
162 /* True means global_bindings_p should return false even if the scope stack
163 says we are in file scope. */
164 bool c_override_global_bindings_to_false;
167 /* Each c_binding structure describes one binding of an identifier to
168 a decl. All the decls in a scope - irrespective of namespace - are
169 chained together by the ->prev field, which (as the name implies)
170 runs in reverse order. All the decls in a given namespace bound to
171 a given identifier are chained by the ->shadowed field, which runs
172 from inner to outer scopes.
174 The ->decl field usually points to a DECL node, but there are two
175 exceptions. In the namespace of type tags, the bound entity is a
176 RECORD_TYPE, UNION_TYPE, or ENUMERAL_TYPE node. If an undeclared
177 identifier is encountered, it is bound to error_mark_node to
178 suppress further errors about that identifier in the current
181 The ->type field stores the type of the declaration in this scope;
182 if NULL, the type is the type of the ->decl field. This is only of
183 relevance for objects with external or internal linkage which may
184 be redeclared in inner scopes, forming composite types that only
185 persist for the duration of those scopes. In the external scope,
186 this stores the composite of all the types declared for this
187 object, visible or not. The ->inner_comp field (used only at file
188 scope) stores whether an incomplete array type at file scope was
189 completed at an inner scope to an array size other than 1.
191 The depth field is copied from the scope structure that holds this
192 decl. It is used to preserve the proper ordering of the ->shadowed
193 field (see bind()) and also for a handful of special-case checks.
194 Finally, the invisible bit is true for a decl which should be
195 ignored for purposes of normal name lookup, and the nested bit is
196 true for a decl that's been bound a second time in an inner scope;
197 in all such cases, the binding in the outer scope will have its
198 invisible bit true. */
200 struct c_binding GTY((chain_next ("%h.prev")))
202 tree decl; /* the decl bound */
203 tree type; /* the type in this scope */
204 tree id; /* the identifier it's bound to */
205 struct c_binding *prev; /* the previous decl in this scope */
206 struct c_binding *shadowed; /* the innermost decl shadowed by this one */
207 unsigned int depth : 28; /* depth of this scope */
208 BOOL_BITFIELD invisible : 1; /* normal lookup should ignore this binding */
209 BOOL_BITFIELD nested : 1; /* do not set DECL_CONTEXT when popping */
210 BOOL_BITFIELD inner_comp : 1; /* incomplete array completed in inner scope */
213 #define B_IN_SCOPE(b1, b2) ((b1)->depth == (b2)->depth)
214 #define B_IN_CURRENT_SCOPE(b) ((b)->depth == current_scope->depth)
215 #define B_IN_FILE_SCOPE(b) ((b)->depth == 1 /*file_scope->depth*/)
216 #define B_IN_EXTERNAL_SCOPE(b) ((b)->depth == 0 /*external_scope->depth*/)
218 #define I_SYMBOL_BINDING(node) \
219 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->symbol_binding)
220 #define I_SYMBOL_DECL(node) \
221 (I_SYMBOL_BINDING(node) ? I_SYMBOL_BINDING(node)->decl : 0)
223 #define I_TAG_BINDING(node) \
224 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->tag_binding)
225 #define I_TAG_DECL(node) \
226 (I_TAG_BINDING(node) ? I_TAG_BINDING(node)->decl : 0)
228 #define I_LABEL_BINDING(node) \
229 (((struct lang_identifier *) IDENTIFIER_NODE_CHECK(node))->label_binding)
230 #define I_LABEL_DECL(node) \
231 (I_LABEL_BINDING(node) ? I_LABEL_BINDING(node)->decl : 0)
233 /* Each C symbol points to three linked lists of c_binding structures.
234 These describe the values of the identifier in the three different
235 namespaces defined by the language. */
237 struct lang_identifier GTY(())
239 struct c_common_identifier common_id;
240 struct c_binding *symbol_binding; /* vars, funcs, constants, typedefs */
241 struct c_binding *tag_binding; /* struct/union/enum tags */
242 struct c_binding *label_binding; /* labels */
245 /* Validate c-lang.c's assumptions. */
246 extern char C_SIZEOF_STRUCT_LANG_IDENTIFIER_isnt_accurate
247 [(sizeof(struct lang_identifier) == C_SIZEOF_STRUCT_LANG_IDENTIFIER) ? 1 : -1];
249 /* The resulting tree type. */
252 GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE"),
253 chain_next ("TREE_CODE (&%h.generic) == INTEGER_TYPE ? (union lang_tree_node *) TYPE_NEXT_VARIANT (&%h.generic) : ((union lang_tree_node *) TREE_CHAIN (&%h.generic))")))
255 union tree_node GTY ((tag ("0"),
256 desc ("tree_node_structure (&%h)")))
258 struct lang_identifier GTY ((tag ("1"))) identifier;
261 /* Each c_scope structure describes the complete contents of one
262 scope. Four scopes are distinguished specially: the innermost or
263 current scope, the innermost function scope, the file scope (always
264 the second to outermost) and the outermost or external scope.
266 Most declarations are recorded in the current scope.
268 All normal label declarations are recorded in the innermost
269 function scope, as are bindings of undeclared identifiers to
270 error_mark_node. (GCC permits nested functions as an extension,
271 hence the 'innermost' qualifier.) Explicitly declared labels
272 (using the __label__ extension) appear in the current scope.
274 Being in the file scope (current_scope == file_scope) causes
275 special behavior in several places below. Also, under some
276 conditions the Objective-C front end records declarations in the
277 file scope even though that isn't the current scope.
279 All declarations with external linkage are recorded in the external
280 scope, even if they aren't visible there; this models the fact that
281 such declarations are visible to the entire program, and (with a
282 bit of cleverness, see pushdecl) allows diagnosis of some violations
283 of C99 6.2.2p7 and 6.2.7p2:
285 If, within the same translation unit, the same identifier appears
286 with both internal and external linkage, the behavior is
289 All declarations that refer to the same object or function shall
290 have compatible type; otherwise, the behavior is undefined.
292 Initially only the built-in declarations, which describe compiler
293 intrinsic functions plus a subset of the standard library, are in
296 The order of the blocks list matters, and it is frequently appended
297 to. To avoid having to walk all the way to the end of the list on
298 each insertion, or reverse the list later, we maintain a pointer to
299 the last list entry. (FIXME: It should be feasible to use a reversed
302 The bindings list is strictly in reverse order of declarations;
303 pop_scope relies on this. */
306 struct c_scope GTY((chain_next ("%h.outer")))
308 /* The scope containing this one. */
309 struct c_scope *outer;
311 /* The next outermost function scope. */
312 struct c_scope *outer_function;
314 /* All bindings in this scope. */
315 struct c_binding *bindings;
317 /* For each scope (except the global one), a chain of BLOCK nodes
318 for all the scopes that were entered and exited one level down. */
322 /* The depth of this scope. Used to keep the ->shadowed chain of
323 bindings sorted innermost to outermost. */
324 unsigned int depth : 28;
326 /* True if we are currently filling this scope with parameter
328 BOOL_BITFIELD parm_flag : 1;
330 /* True if we saw [*] in this scope. Used to give an error messages
331 if these appears in a function definition. */
332 BOOL_BITFIELD had_vla_unspec : 1;
334 /* True if we already complained about forward parameter decls
335 in this scope. This prevents double warnings on
336 foo (int a; int b; ...) */
337 BOOL_BITFIELD warned_forward_parm_decls : 1;
339 /* True if this is the outermost block scope of a function body.
340 This scope contains the parameters, the local variables declared
341 in the outermost block, and all the labels (except those in
342 nested functions, or declared at block scope with __label__). */
343 BOOL_BITFIELD function_body : 1;
345 /* True means make a BLOCK for this scope no matter what. */
346 BOOL_BITFIELD keep : 1;
349 /* The scope currently in effect. */
351 static GTY(()) struct c_scope *current_scope;
353 /* The innermost function scope. Ordinary (not explicitly declared)
354 labels, bindings to error_mark_node, and the lazily-created
355 bindings of __func__ and its friends get this scope. */
357 static GTY(()) struct c_scope *current_function_scope;
359 /* The C file scope. This is reset for each input translation unit. */
361 static GTY(()) struct c_scope *file_scope;
363 /* The outermost scope. This is used for all declarations with
364 external linkage, and only these, hence the name. */
366 static GTY(()) struct c_scope *external_scope;
368 /* A chain of c_scope structures awaiting reuse. */
370 static GTY((deletable)) struct c_scope *scope_freelist;
372 /* A chain of c_binding structures awaiting reuse. */
374 static GTY((deletable)) struct c_binding *binding_freelist;
376 /* Append VAR to LIST in scope SCOPE. */
377 #define SCOPE_LIST_APPEND(scope, list, decl) do { \
378 struct c_scope *s_ = (scope); \
380 if (s_->list##_last) \
381 BLOCK_CHAIN (s_->list##_last) = d_; \
384 s_->list##_last = d_; \
387 /* Concatenate FROM in scope FSCOPE onto TO in scope TSCOPE. */
388 #define SCOPE_LIST_CONCAT(tscope, to, fscope, from) do { \
389 struct c_scope *t_ = (tscope); \
390 struct c_scope *f_ = (fscope); \
392 BLOCK_CHAIN (t_->to##_last) = f_->from; \
395 t_->to##_last = f_->from##_last; \
398 /* True means unconditionally make a BLOCK for the next scope pushed. */
400 static bool keep_next_level_flag;
402 /* True means the next call to push_scope will be the outermost scope
403 of a function body, so do not push a new scope, merely cease
404 expecting parameter decls. */
406 static bool next_is_function_body;
408 /* Forward declarations. */
409 static tree lookup_name_in_scope (tree, struct c_scope *);
410 static tree c_make_fname_decl (tree, int);
411 static tree grokdeclarator (const struct c_declarator *,
412 struct c_declspecs *,
413 enum decl_context, bool, tree *, tree *,
414 enum deprecated_states);
415 static tree grokparms (struct c_arg_info *, bool);
416 static void layout_array_type (tree);
418 /* T is a statement. Add it to the statement-tree. This is the
419 C/ObjC version--C++ has a slightly different version of this
425 enum tree_code code = TREE_CODE (t);
427 if (CAN_HAVE_LOCATION_P (t) && code != LABEL_EXPR)
429 if (!EXPR_HAS_LOCATION (t))
430 SET_EXPR_LOCATION (t, input_location);
433 if (code == LABEL_EXPR || code == CASE_LABEL_EXPR)
434 STATEMENT_LIST_HAS_LABEL (cur_stmt_list) = 1;
436 /* Add T to the statement-tree. Non-side-effect statements need to be
437 recorded during statement expressions. */
438 append_to_statement_list_force (t, &cur_stmt_list);
445 c_print_identifier (FILE *file, tree node, int indent)
447 print_node (file, "symbol", I_SYMBOL_DECL (node), indent + 4);
448 print_node (file, "tag", I_TAG_DECL (node), indent + 4);
449 print_node (file, "label", I_LABEL_DECL (node), indent + 4);
450 if (C_IS_RESERVED_WORD (node) && C_RID_CODE (node) != RID_CXX_COMPAT_WARN)
452 tree rid = ridpointers[C_RID_CODE (node)];
453 indent_to (file, indent + 4);
454 fprintf (file, "rid %p \"%s\"",
455 (void *) rid, IDENTIFIER_POINTER (rid));
459 /* Establish a binding between NAME, an IDENTIFIER_NODE, and DECL,
460 which may be any of several kinds of DECL or TYPE or error_mark_node,
461 in the scope SCOPE. */
463 bind (tree name, tree decl, struct c_scope *scope, bool invisible, bool nested)
465 struct c_binding *b, **here;
467 if (binding_freelist)
469 b = binding_freelist;
470 binding_freelist = b->prev;
473 b = GGC_NEW (struct c_binding);
478 b->depth = scope->depth;
479 b->invisible = invisible;
485 b->prev = scope->bindings;
491 switch (TREE_CODE (decl))
493 case LABEL_DECL: here = &I_LABEL_BINDING (name); break;
496 case RECORD_TYPE: here = &I_TAG_BINDING (name); break;
502 case ERROR_MARK: here = &I_SYMBOL_BINDING (name); break;
508 /* Locate the appropriate place in the chain of shadowed decls
509 to insert this binding. Normally, scope == current_scope and
510 this does nothing. */
511 while (*here && (*here)->depth > scope->depth)
512 here = &(*here)->shadowed;
518 /* Clear the binding structure B, stick it on the binding_freelist,
519 and return the former value of b->prev. This is used by pop_scope
520 and get_parm_info to iterate destructively over all the bindings
521 from a given scope. */
522 static struct c_binding *
523 free_binding_and_advance (struct c_binding *b)
525 struct c_binding *prev = b->prev;
527 memset (b, 0, sizeof (struct c_binding));
528 b->prev = binding_freelist;
529 binding_freelist = b;
535 /* Hook called at end of compilation to assume 1 elt
536 for a file-scope tentative array defn that wasn't complete before. */
539 c_finish_incomplete_decl (tree decl)
541 if (TREE_CODE (decl) == VAR_DECL)
543 tree type = TREE_TYPE (decl);
544 if (type != error_mark_node
545 && TREE_CODE (type) == ARRAY_TYPE
546 && !DECL_EXTERNAL (decl)
547 && TYPE_DOMAIN (type) == 0)
549 warning (0, "array %q+D assumed to have one element", decl);
551 complete_array_type (&TREE_TYPE (decl), NULL_TREE, true);
553 layout_decl (decl, 0);
558 /* The Objective-C front-end often needs to determine the current scope. */
561 objc_get_current_scope (void)
563 return current_scope;
566 /* The following function is used only by Objective-C. It needs to live here
567 because it accesses the innards of c_scope. */
570 objc_mark_locals_volatile (void *enclosing_blk)
572 struct c_scope *scope;
575 for (scope = current_scope;
576 scope && scope != enclosing_blk;
577 scope = scope->outer)
579 for (b = scope->bindings; b; b = b->prev)
580 objc_volatilize_decl (b->decl);
582 /* Do not climb up past the current function. */
583 if (scope->function_body)
588 /* Nonzero if we are currently in file scope. */
591 global_bindings_p (void)
593 return current_scope == file_scope && !c_override_global_bindings_to_false;
597 keep_next_level (void)
599 keep_next_level_flag = true;
602 /* Identify this scope as currently being filled with parameters. */
605 declare_parm_level (void)
607 current_scope->parm_flag = true;
613 if (next_is_function_body)
615 /* This is the transition from the parameters to the top level
616 of the function body. These are the same scope
617 (C99 6.2.1p4,6) so we do not push another scope structure.
618 next_is_function_body is set only by store_parm_decls, which
619 in turn is called when and only when we are about to
620 encounter the opening curly brace for the function body.
622 The outermost block of a function always gets a BLOCK node,
623 because the debugging output routines expect that each
624 function has at least one BLOCK. */
625 current_scope->parm_flag = false;
626 current_scope->function_body = true;
627 current_scope->keep = true;
628 current_scope->outer_function = current_function_scope;
629 current_function_scope = current_scope;
631 keep_next_level_flag = false;
632 next_is_function_body = false;
636 struct c_scope *scope;
639 scope = scope_freelist;
640 scope_freelist = scope->outer;
643 scope = GGC_CNEW (struct c_scope);
645 scope->keep = keep_next_level_flag;
646 scope->outer = current_scope;
647 scope->depth = current_scope ? (current_scope->depth + 1) : 0;
649 /* Check for scope depth overflow. Unlikely (2^28 == 268,435,456) but
651 if (current_scope && scope->depth == 0)
654 sorry ("GCC supports only %u nested scopes", scope->depth);
657 current_scope = scope;
658 keep_next_level_flag = false;
662 /* Set the TYPE_CONTEXT of all of TYPE's variants to CONTEXT. */
665 set_type_context (tree type, tree context)
667 for (type = TYPE_MAIN_VARIANT (type); type;
668 type = TYPE_NEXT_VARIANT (type))
669 TYPE_CONTEXT (type) = context;
672 /* Exit a scope. Restore the state of the identifier-decl mappings
673 that were in effect when this scope was entered. Return a BLOCK
674 node containing all the DECLs in this scope that are of interest
675 to debug info generation. */
680 struct c_scope *scope = current_scope;
681 tree block, context, p;
684 bool functionbody = scope->function_body;
685 bool keep = functionbody || scope->keep || scope->bindings;
687 c_end_vm_scope (scope->depth);
689 /* If appropriate, create a BLOCK to record the decls for the life
694 block = make_node (BLOCK);
695 BLOCK_SUBBLOCKS (block) = scope->blocks;
696 TREE_USED (block) = 1;
698 /* In each subblock, record that this is its superior. */
699 for (p = scope->blocks; p; p = BLOCK_CHAIN (p))
700 BLOCK_SUPERCONTEXT (p) = block;
702 BLOCK_VARS (block) = 0;
705 /* The TYPE_CONTEXTs for all of the tagged types belonging to this
706 scope must be set so that they point to the appropriate
707 construct, i.e. either to the current FUNCTION_DECL node, or
708 else to the BLOCK node we just constructed.
710 Note that for tagged types whose scope is just the formal
711 parameter list for some function type specification, we can't
712 properly set their TYPE_CONTEXTs here, because we don't have a
713 pointer to the appropriate FUNCTION_TYPE node readily available
714 to us. For those cases, the TYPE_CONTEXTs of the relevant tagged
715 type nodes get set in `grokdeclarator' as soon as we have created
716 the FUNCTION_TYPE node which will represent the "scope" for these
717 "parameter list local" tagged types. */
718 if (scope->function_body)
719 context = current_function_decl;
720 else if (scope == file_scope)
722 tree file_decl = build_decl (TRANSLATION_UNIT_DECL, 0, 0);
723 TREE_CHAIN (file_decl) = all_translation_units;
724 all_translation_units = file_decl;
730 /* Clear all bindings in this scope. */
731 for (b = scope->bindings; b; b = free_binding_and_advance (b))
734 switch (TREE_CODE (p))
737 /* Warnings for unused labels, errors for undefined labels. */
738 if (TREE_USED (p) && !DECL_INITIAL (p))
740 error ("label %q+D used but not defined", p);
741 DECL_INITIAL (p) = error_mark_node;
744 warn_for_unused_label (p);
746 /* Labels go in BLOCK_VARS. */
747 TREE_CHAIN (p) = BLOCK_VARS (block);
748 BLOCK_VARS (block) = p;
749 gcc_assert (I_LABEL_BINDING (b->id) == b);
750 I_LABEL_BINDING (b->id) = b->shadowed;
756 set_type_context (p, context);
758 /* Types may not have tag-names, in which case the type
759 appears in the bindings list with b->id NULL. */
762 gcc_assert (I_TAG_BINDING (b->id) == b);
763 I_TAG_BINDING (b->id) = b->shadowed;
768 /* Propagate TREE_ADDRESSABLE from nested functions to their
769 containing functions. */
770 if (!TREE_ASM_WRITTEN (p)
771 && DECL_INITIAL (p) != 0
772 && TREE_ADDRESSABLE (p)
773 && DECL_ABSTRACT_ORIGIN (p) != 0
774 && DECL_ABSTRACT_ORIGIN (p) != p)
775 TREE_ADDRESSABLE (DECL_ABSTRACT_ORIGIN (p)) = 1;
776 if (!DECL_EXTERNAL (p)
778 && scope != file_scope
779 && scope != external_scope)
781 error ("nested function %q+D declared but never defined", p);
782 undef_nested_function = true;
784 /* C99 6.7.4p6: "a function with external linkage... declared
785 with an inline function specifier ... shall also be defined in the
786 same translation unit." */
787 else if (DECL_DECLARED_INLINE_P (p)
790 && !flag_gnu89_inline)
791 pedwarn (0, "inline function %q+D declared but never defined", p);
796 /* Warnings for unused variables. */
798 && !TREE_NO_WARNING (p)
799 && !DECL_IN_SYSTEM_HEADER (p)
801 && !DECL_ARTIFICIAL (p)
802 && scope != file_scope
803 && scope != external_scope)
804 warning (OPT_Wunused_variable, "unused variable %q+D", p);
808 error ("type of array %q+D completed incompatibly with"
809 " implicit initialization", p);
816 /* All of these go in BLOCK_VARS, but only if this is the
817 binding in the home scope. */
820 TREE_CHAIN (p) = BLOCK_VARS (block);
821 BLOCK_VARS (block) = p;
823 /* If this is the file scope, and we are processing more
824 than one translation unit in this compilation, set
825 DECL_CONTEXT of each decl to the TRANSLATION_UNIT_DECL.
826 This makes same_translation_unit_p work, and causes
827 static declarations to be given disambiguating suffixes. */
828 if (scope == file_scope && num_in_fnames > 1)
830 DECL_CONTEXT (p) = context;
831 if (TREE_CODE (p) == TYPE_DECL)
832 set_type_context (TREE_TYPE (p), context);
836 /* Parameters go in DECL_ARGUMENTS, not BLOCK_VARS, and have
837 already been put there by store_parm_decls. Unused-
838 parameter warnings are handled by function.c.
839 error_mark_node obviously does not go in BLOCK_VARS and
840 does not get unused-variable warnings. */
843 /* It is possible for a decl not to have a name. We get
844 here with b->id NULL in this case. */
847 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
848 I_SYMBOL_BINDING (b->id) = b->shadowed;
849 if (b->shadowed && b->shadowed->type)
850 TREE_TYPE (b->shadowed->decl) = b->shadowed->type;
860 /* Dispose of the block that we just made inside some higher level. */
861 if ((scope->function_body || scope == file_scope) && context)
863 DECL_INITIAL (context) = block;
864 BLOCK_SUPERCONTEXT (block) = context;
866 else if (scope->outer)
869 SCOPE_LIST_APPEND (scope->outer, blocks, block);
870 /* If we did not make a block for the scope just exited, any
871 blocks made for inner scopes must be carried forward so they
872 will later become subblocks of something else. */
873 else if (scope->blocks)
874 SCOPE_LIST_CONCAT (scope->outer, blocks, scope, blocks);
877 /* Pop the current scope, and free the structure for reuse. */
878 current_scope = scope->outer;
879 if (scope->function_body)
880 current_function_scope = scope->outer_function;
882 memset (scope, 0, sizeof (struct c_scope));
883 scope->outer = scope_freelist;
884 scope_freelist = scope;
890 push_file_scope (void)
898 file_scope = current_scope;
900 start_fname_decls ();
902 for (decl = visible_builtins; decl; decl = TREE_CHAIN (decl))
903 bind (DECL_NAME (decl), decl, file_scope,
904 /*invisible=*/false, /*nested=*/true);
908 pop_file_scope (void)
910 /* In case there were missing closebraces, get us back to the global
912 while (current_scope != file_scope)
915 /* __FUNCTION__ is defined at file scope (""). This
916 call may not be necessary as my tests indicate it
917 still works without it. */
918 finish_fname_decls ();
920 /* This is the point to write out a PCH if we're doing that.
921 In that case we do not want to do anything else. */
924 c_common_write_pch ();
928 /* Pop off the file scope and close this translation unit. */
932 maybe_apply_pending_pragma_weaks ();
933 cgraph_finalize_compilation_unit ();
937 /* Push a definition or a declaration of struct, union or enum tag "name".
938 "type" should be the type node.
939 We assume that the tag "name" is not already defined.
941 Note that the definition may really be just a forward reference.
942 In that case, the TYPE_SIZE will be zero. */
945 pushtag (tree name, tree type)
947 /* Record the identifier as the type's name if it has none. */
948 if (name && !TYPE_NAME (type))
949 TYPE_NAME (type) = name;
950 bind (name, type, current_scope, /*invisible=*/false, /*nested=*/false);
952 /* Create a fake NULL-named TYPE_DECL node whose TREE_TYPE will be the
953 tagged type we just added to the current scope. This fake
954 NULL-named TYPE_DECL node helps dwarfout.c to know when it needs
955 to output a representation of a tagged type, and it also gives
956 us a convenient place to record the "scope start" address for the
959 TYPE_STUB_DECL (type) = pushdecl (build_decl (TYPE_DECL, NULL_TREE, type));
961 /* An approximation for now, so we can tell this is a function-scope tag.
962 This will be updated in pop_scope. */
963 TYPE_CONTEXT (type) = DECL_CONTEXT (TYPE_STUB_DECL (type));
966 /* Subroutine of compare_decls. Allow harmless mismatches in return
967 and argument types provided that the type modes match. This function
968 return a unified type given a suitable match, and 0 otherwise. */
971 match_builtin_function_types (tree newtype, tree oldtype)
973 tree newrettype, oldrettype;
974 tree newargs, oldargs;
975 tree trytype, tryargs;
977 /* Accept the return type of the new declaration if same modes. */
978 oldrettype = TREE_TYPE (oldtype);
979 newrettype = TREE_TYPE (newtype);
981 if (TYPE_MODE (oldrettype) != TYPE_MODE (newrettype))
984 oldargs = TYPE_ARG_TYPES (oldtype);
985 newargs = TYPE_ARG_TYPES (newtype);
988 while (oldargs || newargs)
992 || !TREE_VALUE (oldargs)
993 || !TREE_VALUE (newargs)
994 || TYPE_MODE (TREE_VALUE (oldargs))
995 != TYPE_MODE (TREE_VALUE (newargs)))
998 oldargs = TREE_CHAIN (oldargs);
999 newargs = TREE_CHAIN (newargs);
1002 trytype = build_function_type (newrettype, tryargs);
1003 return build_type_attribute_variant (trytype, TYPE_ATTRIBUTES (oldtype));
1006 /* Subroutine of diagnose_mismatched_decls. Check for function type
1007 mismatch involving an empty arglist vs a nonempty one and give clearer
1010 diagnose_arglist_conflict (tree newdecl, tree olddecl,
1011 tree newtype, tree oldtype)
1015 if (TREE_CODE (olddecl) != FUNCTION_DECL
1016 || !comptypes (TREE_TYPE (oldtype), TREE_TYPE (newtype))
1017 || !((TYPE_ARG_TYPES (oldtype) == 0 && DECL_INITIAL (olddecl) == 0)
1019 (TYPE_ARG_TYPES (newtype) == 0 && DECL_INITIAL (newdecl) == 0)))
1022 t = TYPE_ARG_TYPES (oldtype);
1024 t = TYPE_ARG_TYPES (newtype);
1025 for (; t; t = TREE_CHAIN (t))
1027 tree type = TREE_VALUE (t);
1029 if (TREE_CHAIN (t) == 0
1030 && TYPE_MAIN_VARIANT (type) != void_type_node)
1032 inform ("a parameter list with an ellipsis can%'t match "
1033 "an empty parameter name list declaration");
1037 if (c_type_promotes_to (type) != type)
1039 inform ("an argument type that has a default promotion can%'t match "
1040 "an empty parameter name list declaration");
1046 /* Another subroutine of diagnose_mismatched_decls. OLDDECL is an
1047 old-style function definition, NEWDECL is a prototype declaration.
1048 Diagnose inconsistencies in the argument list. Returns TRUE if
1049 the prototype is compatible, FALSE if not. */
1051 validate_proto_after_old_defn (tree newdecl, tree newtype, tree oldtype)
1053 tree newargs, oldargs;
1056 #define END_OF_ARGLIST(t) ((t) == void_type_node)
1058 oldargs = TYPE_ACTUAL_ARG_TYPES (oldtype);
1059 newargs = TYPE_ARG_TYPES (newtype);
1064 tree oldargtype = TREE_VALUE (oldargs);
1065 tree newargtype = TREE_VALUE (newargs);
1067 if (oldargtype == error_mark_node || newargtype == error_mark_node)
1070 oldargtype = TYPE_MAIN_VARIANT (oldargtype);
1071 newargtype = TYPE_MAIN_VARIANT (newargtype);
1073 if (END_OF_ARGLIST (oldargtype) && END_OF_ARGLIST (newargtype))
1076 /* Reaching the end of just one list means the two decls don't
1077 agree on the number of arguments. */
1078 if (END_OF_ARGLIST (oldargtype))
1080 error ("prototype for %q+D declares more arguments "
1081 "than previous old-style definition", newdecl);
1084 else if (END_OF_ARGLIST (newargtype))
1086 error ("prototype for %q+D declares fewer arguments "
1087 "than previous old-style definition", newdecl);
1091 /* Type for passing arg must be consistent with that declared
1093 else if (!comptypes (oldargtype, newargtype))
1095 error ("prototype for %q+D declares argument %d"
1096 " with incompatible type",
1101 oldargs = TREE_CHAIN (oldargs);
1102 newargs = TREE_CHAIN (newargs);
1106 /* If we get here, no errors were found, but do issue a warning
1107 for this poor-style construct. */
1108 warning (0, "prototype for %q+D follows non-prototype definition",
1111 #undef END_OF_ARGLIST
1114 /* Subroutine of diagnose_mismatched_decls. Report the location of DECL,
1115 first in a pair of mismatched declarations, using the diagnostic
1118 locate_old_decl (tree decl, void (*diag)(const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2))
1120 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1122 else if (DECL_INITIAL (decl))
1123 diag (G_("previous definition of %q+D was here"), decl);
1124 else if (C_DECL_IMPLICIT (decl))
1125 diag (G_("previous implicit declaration of %q+D was here"), decl);
1127 diag (G_("previous declaration of %q+D was here"), decl);
1130 /* Subroutine of duplicate_decls. Compare NEWDECL to OLDDECL.
1131 Returns true if the caller should proceed to merge the two, false
1132 if OLDDECL should simply be discarded. As a side effect, issues
1133 all necessary diagnostics for invalid or poor-style combinations.
1134 If it returns true, writes the types of NEWDECL and OLDDECL to
1135 *NEWTYPEP and *OLDTYPEP - these may have been adjusted from
1136 TREE_TYPE (NEWDECL, OLDDECL) respectively. */
1139 diagnose_mismatched_decls (tree newdecl, tree olddecl,
1140 tree *newtypep, tree *oldtypep)
1142 tree newtype, oldtype;
1143 bool pedwarned = false;
1144 bool warned = false;
1147 #define DECL_EXTERN_INLINE(DECL) (DECL_DECLARED_INLINE_P (DECL) \
1148 && DECL_EXTERNAL (DECL))
1150 /* If we have error_mark_node for either decl or type, just discard
1151 the previous decl - we're in an error cascade already. */
1152 if (olddecl == error_mark_node || newdecl == error_mark_node)
1154 *oldtypep = oldtype = TREE_TYPE (olddecl);
1155 *newtypep = newtype = TREE_TYPE (newdecl);
1156 if (oldtype == error_mark_node || newtype == error_mark_node)
1159 /* Two different categories of symbol altogether. This is an error
1160 unless OLDDECL is a builtin. OLDDECL will be discarded in any case. */
1161 if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1163 if (!(TREE_CODE (olddecl) == FUNCTION_DECL
1164 && DECL_BUILT_IN (olddecl)
1165 && !C_DECL_DECLARED_BUILTIN (olddecl)))
1167 error ("%q+D redeclared as different kind of symbol", newdecl);
1168 locate_old_decl (olddecl, error);
1170 else if (TREE_PUBLIC (newdecl))
1171 warning (0, "built-in function %q+D declared as non-function",
1174 warning (OPT_Wshadow, "declaration of %q+D shadows "
1175 "a built-in function", newdecl);
1179 /* Enumerators have no linkage, so may only be declared once in a
1181 if (TREE_CODE (olddecl) == CONST_DECL)
1183 error ("redeclaration of enumerator %q+D", newdecl);
1184 locate_old_decl (olddecl, error);
1188 if (!comptypes (oldtype, newtype))
1190 if (TREE_CODE (olddecl) == FUNCTION_DECL
1191 && DECL_BUILT_IN (olddecl) && !C_DECL_DECLARED_BUILTIN (olddecl))
1193 /* Accept harmless mismatch in function types.
1194 This is for the ffs and fprintf builtins. */
1195 tree trytype = match_builtin_function_types (newtype, oldtype);
1197 if (trytype && comptypes (newtype, trytype))
1198 *oldtypep = oldtype = trytype;
1201 /* If types don't match for a built-in, throw away the
1202 built-in. No point in calling locate_old_decl here, it
1203 won't print anything. */
1204 warning (0, "conflicting types for built-in function %q+D",
1209 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1210 && DECL_IS_BUILTIN (olddecl))
1212 /* A conflicting function declaration for a predeclared
1213 function that isn't actually built in. Objective C uses
1214 these. The new declaration silently overrides everything
1215 but the volatility (i.e. noreturn) indication. See also
1216 below. FIXME: Make Objective C use normal builtins. */
1217 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1220 /* Permit void foo (...) to match int foo (...) if the latter is
1221 the definition and implicit int was used. See
1222 c-torture/compile/920625-2.c. */
1223 else if (TREE_CODE (newdecl) == FUNCTION_DECL && DECL_INITIAL (newdecl)
1224 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == void_type_node
1225 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == integer_type_node
1226 && C_FUNCTION_IMPLICIT_INT (newdecl) && !DECL_INITIAL (olddecl))
1228 pedwarn (0, "conflicting types for %q+D", newdecl);
1229 /* Make sure we keep void as the return type. */
1230 TREE_TYPE (newdecl) = *newtypep = newtype = oldtype;
1231 C_FUNCTION_IMPLICIT_INT (newdecl) = 0;
1234 /* Permit void foo (...) to match an earlier call to foo (...) with
1235 no declared type (thus, implicitly int). */
1236 else if (TREE_CODE (newdecl) == FUNCTION_DECL
1237 && TYPE_MAIN_VARIANT (TREE_TYPE (newtype)) == void_type_node
1238 && TYPE_MAIN_VARIANT (TREE_TYPE (oldtype)) == integer_type_node
1239 && C_DECL_IMPLICIT (olddecl) && !DECL_INITIAL (olddecl))
1241 pedwarn (0, "conflicting types for %q+D", newdecl);
1242 /* Make sure we keep void as the return type. */
1243 TREE_TYPE (olddecl) = *oldtypep = oldtype = newtype;
1248 if (TYPE_QUALS (newtype) != TYPE_QUALS (oldtype))
1249 error ("conflicting type qualifiers for %q+D", newdecl);
1251 error ("conflicting types for %q+D", newdecl);
1252 diagnose_arglist_conflict (newdecl, olddecl, newtype, oldtype);
1253 locate_old_decl (olddecl, error);
1258 /* Redeclaration of a type is a constraint violation (6.7.2.3p1),
1259 but silently ignore the redeclaration if either is in a system
1260 header. (Conflicting redeclarations were handled above.) */
1261 if (TREE_CODE (newdecl) == TYPE_DECL)
1263 if (DECL_IN_SYSTEM_HEADER (newdecl)
1264 || DECL_IN_SYSTEM_HEADER (olddecl)
1265 || TREE_NO_WARNING (newdecl)
1266 || TREE_NO_WARNING (olddecl))
1267 return true; /* Allow OLDDECL to continue in use. */
1269 error ("redefinition of typedef %q+D", newdecl);
1270 locate_old_decl (olddecl, error);
1274 /* Function declarations can either be 'static' or 'extern' (no
1275 qualifier is equivalent to 'extern' - C99 6.2.2p5) and therefore
1276 can never conflict with each other on account of linkage
1277 (6.2.2p4). Multiple definitions are not allowed (6.9p3,5) but
1278 gnu89 mode permits two definitions if one is 'extern inline' and
1279 one is not. The non- extern-inline definition supersedes the
1280 extern-inline definition. */
1282 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
1284 /* If you declare a built-in function name as static, or
1285 define the built-in with an old-style definition (so we
1286 can't validate the argument list) the built-in definition is
1287 overridden, but optionally warn this was a bad choice of name. */
1288 if (DECL_BUILT_IN (olddecl)
1289 && !C_DECL_DECLARED_BUILTIN (olddecl)
1290 && (!TREE_PUBLIC (newdecl)
1291 || (DECL_INITIAL (newdecl)
1292 && !TYPE_ARG_TYPES (TREE_TYPE (newdecl)))))
1294 warning (OPT_Wshadow, "declaration of %q+D shadows "
1295 "a built-in function", newdecl);
1296 /* Discard the old built-in function. */
1300 if (DECL_INITIAL (newdecl))
1302 if (DECL_INITIAL (olddecl))
1304 /* If both decls are in the same TU and the new declaration
1305 isn't overriding an extern inline reject the new decl.
1306 In c99, no overriding is allowed in the same translation
1308 if ((!DECL_EXTERN_INLINE (olddecl)
1309 || DECL_EXTERN_INLINE (newdecl)
1310 || (!flag_gnu89_inline
1311 && (!DECL_DECLARED_INLINE_P (olddecl)
1312 || !lookup_attribute ("gnu_inline",
1313 DECL_ATTRIBUTES (olddecl)))
1314 && (!DECL_DECLARED_INLINE_P (newdecl)
1315 || !lookup_attribute ("gnu_inline",
1316 DECL_ATTRIBUTES (newdecl))))
1318 && same_translation_unit_p (newdecl, olddecl))
1320 error ("redefinition of %q+D", newdecl);
1321 locate_old_decl (olddecl, error);
1326 /* If we have a prototype after an old-style function definition,
1327 the argument types must be checked specially. */
1328 else if (DECL_INITIAL (olddecl)
1329 && !TYPE_ARG_TYPES (oldtype) && TYPE_ARG_TYPES (newtype)
1330 && TYPE_ACTUAL_ARG_TYPES (oldtype)
1331 && !validate_proto_after_old_defn (newdecl, newtype, oldtype))
1333 locate_old_decl (olddecl, error);
1336 /* A non-static declaration (even an "extern") followed by a
1337 static declaration is undefined behavior per C99 6.2.2p3-5,7.
1338 The same is true for a static forward declaration at block
1339 scope followed by a non-static declaration/definition at file
1340 scope. Static followed by non-static at the same scope is
1341 not undefined behavior, and is the most convenient way to get
1342 some effects (see e.g. what unwind-dw2-fde-glibc.c does to
1343 the definition of _Unwind_Find_FDE in unwind-dw2-fde.c), but
1344 we do diagnose it if -Wtraditional. */
1345 if (TREE_PUBLIC (olddecl) && !TREE_PUBLIC (newdecl))
1347 /* Two exceptions to the rule. If olddecl is an extern
1348 inline, or a predeclared function that isn't actually
1349 built in, newdecl silently overrides olddecl. The latter
1350 occur only in Objective C; see also above. (FIXME: Make
1351 Objective C use normal builtins.) */
1352 if (!DECL_IS_BUILTIN (olddecl)
1353 && !DECL_EXTERN_INLINE (olddecl))
1355 error ("static declaration of %q+D follows "
1356 "non-static declaration", newdecl);
1357 locate_old_decl (olddecl, error);
1361 else if (TREE_PUBLIC (newdecl) && !TREE_PUBLIC (olddecl))
1363 if (DECL_CONTEXT (olddecl))
1365 error ("non-static declaration of %q+D follows "
1366 "static declaration", newdecl);
1367 locate_old_decl (olddecl, error);
1370 else if (warn_traditional)
1372 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1373 "follows static declaration", newdecl);
1378 /* Make sure gnu_inline attribute is either not present, or
1379 present on all inline decls. */
1380 if (DECL_DECLARED_INLINE_P (olddecl)
1381 && DECL_DECLARED_INLINE_P (newdecl))
1383 bool newa = lookup_attribute ("gnu_inline",
1384 DECL_ATTRIBUTES (newdecl)) != NULL;
1385 bool olda = lookup_attribute ("gnu_inline",
1386 DECL_ATTRIBUTES (olddecl)) != NULL;
1389 error ("%<gnu_inline%> attribute present on %q+D",
1390 newa ? newdecl : olddecl);
1391 error ("%Jbut not here", newa ? olddecl : newdecl);
1395 else if (TREE_CODE (newdecl) == VAR_DECL)
1397 /* Only variables can be thread-local, and all declarations must
1398 agree on this property. */
1399 if (C_DECL_THREADPRIVATE_P (olddecl) && !DECL_THREAD_LOCAL_P (newdecl))
1401 /* Nothing to check. Since OLDDECL is marked threadprivate
1402 and NEWDECL does not have a thread-local attribute, we
1403 will merge the threadprivate attribute into NEWDECL. */
1406 else if (DECL_THREAD_LOCAL_P (newdecl) != DECL_THREAD_LOCAL_P (olddecl))
1408 if (DECL_THREAD_LOCAL_P (newdecl))
1409 error ("thread-local declaration of %q+D follows "
1410 "non-thread-local declaration", newdecl);
1412 error ("non-thread-local declaration of %q+D follows "
1413 "thread-local declaration", newdecl);
1415 locate_old_decl (olddecl, error);
1419 /* Multiple initialized definitions are not allowed (6.9p3,5). */
1420 if (DECL_INITIAL (newdecl) && DECL_INITIAL (olddecl))
1422 error ("redefinition of %q+D", newdecl);
1423 locate_old_decl (olddecl, error);
1427 /* Objects declared at file scope: if the first declaration had
1428 external linkage (even if it was an external reference) the
1429 second must have external linkage as well, or the behavior is
1430 undefined. If the first declaration had internal linkage, then
1431 the second must too, or else be an external reference (in which
1432 case the composite declaration still has internal linkage).
1433 As for function declarations, we warn about the static-then-
1434 extern case only for -Wtraditional. See generally 6.2.2p3-5,7. */
1435 if (DECL_FILE_SCOPE_P (newdecl)
1436 && TREE_PUBLIC (newdecl) != TREE_PUBLIC (olddecl))
1438 if (DECL_EXTERNAL (newdecl))
1440 if (!DECL_FILE_SCOPE_P (olddecl))
1442 error ("extern declaration of %q+D follows "
1443 "declaration with no linkage", newdecl);
1444 locate_old_decl (olddecl, error);
1447 else if (warn_traditional)
1449 warning (OPT_Wtraditional, "non-static declaration of %q+D "
1450 "follows static declaration", newdecl);
1456 if (TREE_PUBLIC (newdecl))
1457 error ("non-static declaration of %q+D follows "
1458 "static declaration", newdecl);
1460 error ("static declaration of %q+D follows "
1461 "non-static declaration", newdecl);
1463 locate_old_decl (olddecl, error);
1467 /* Two objects with the same name declared at the same block
1468 scope must both be external references (6.7p3). */
1469 else if (!DECL_FILE_SCOPE_P (newdecl))
1471 if (DECL_EXTERNAL (newdecl))
1473 /* Extern with initializer at block scope, which will
1474 already have received an error. */
1476 else if (DECL_EXTERNAL (olddecl))
1478 error ("declaration of %q+D with no linkage follows "
1479 "extern declaration", newdecl);
1480 locate_old_decl (olddecl, error);
1484 error ("redeclaration of %q+D with no linkage", newdecl);
1485 locate_old_decl (olddecl, error);
1493 /* All decls must agree on a visibility. */
1494 if (CODE_CONTAINS_STRUCT (TREE_CODE (newdecl), TS_DECL_WITH_VIS)
1495 && DECL_VISIBILITY_SPECIFIED (newdecl) && DECL_VISIBILITY_SPECIFIED (olddecl)
1496 && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
1498 warning (0, "redeclaration of %q+D with different visibility "
1499 "(old visibility preserved)", newdecl);
1503 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1505 /* Diagnose inline __attribute__ ((noinline)) which is silly. */
1506 if (DECL_DECLARED_INLINE_P (newdecl)
1507 && lookup_attribute ("noinline", DECL_ATTRIBUTES (olddecl)))
1509 warning (OPT_Wattributes, "inline declaration of %qD follows "
1510 "declaration with attribute noinline", newdecl);
1513 else if (DECL_DECLARED_INLINE_P (olddecl)
1514 && lookup_attribute ("noinline", DECL_ATTRIBUTES (newdecl)))
1516 warning (OPT_Wattributes, "declaration of %q+D with attribute "
1517 "noinline follows inline declaration ", newdecl);
1521 else /* PARM_DECL, VAR_DECL */
1523 /* Redeclaration of a parameter is a constraint violation (this is
1524 not explicitly stated, but follows from C99 6.7p3 [no more than
1525 one declaration of the same identifier with no linkage in the
1526 same scope, except type tags] and 6.2.2p6 [parameters have no
1527 linkage]). We must check for a forward parameter declaration,
1528 indicated by TREE_ASM_WRITTEN on the old declaration - this is
1529 an extension, the mandatory diagnostic for which is handled by
1530 mark_forward_parm_decls. */
1532 if (TREE_CODE (newdecl) == PARM_DECL
1533 && (!TREE_ASM_WRITTEN (olddecl) || TREE_ASM_WRITTEN (newdecl)))
1535 error ("redefinition of parameter %q+D", newdecl);
1536 locate_old_decl (olddecl, error);
1541 /* Optional warning for completely redundant decls. */
1542 if (!warned && !pedwarned
1543 && warn_redundant_decls
1544 /* Don't warn about a function declaration followed by a
1546 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1547 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl))
1548 /* Don't warn about redundant redeclarations of builtins. */
1549 && !(TREE_CODE (newdecl) == FUNCTION_DECL
1550 && !DECL_BUILT_IN (newdecl)
1551 && DECL_BUILT_IN (olddecl)
1552 && !C_DECL_DECLARED_BUILTIN (olddecl))
1553 /* Don't warn about an extern followed by a definition. */
1554 && !(DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl))
1555 /* Don't warn about forward parameter decls. */
1556 && !(TREE_CODE (newdecl) == PARM_DECL
1557 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
1558 /* Don't warn about a variable definition following a declaration. */
1559 && !(TREE_CODE (newdecl) == VAR_DECL
1560 && DECL_INITIAL (newdecl) && !DECL_INITIAL (olddecl)))
1562 warning (OPT_Wredundant_decls, "redundant redeclaration of %q+D",
1567 /* Report location of previous decl/defn in a consistent manner. */
1568 if (warned || pedwarned)
1569 locate_old_decl (olddecl, pedwarned ? pedwarn0 : warning0);
1571 #undef DECL_EXTERN_INLINE
1576 /* Subroutine of duplicate_decls. NEWDECL has been found to be
1577 consistent with OLDDECL, but carries new information. Merge the
1578 new information into OLDDECL. This function issues no
1582 merge_decls (tree newdecl, tree olddecl, tree newtype, tree oldtype)
1584 bool new_is_definition = (TREE_CODE (newdecl) == FUNCTION_DECL
1585 && DECL_INITIAL (newdecl) != 0);
1586 bool new_is_prototype = (TREE_CODE (newdecl) == FUNCTION_DECL
1587 && TYPE_ARG_TYPES (TREE_TYPE (newdecl)) != 0);
1588 bool old_is_prototype = (TREE_CODE (olddecl) == FUNCTION_DECL
1589 && TYPE_ARG_TYPES (TREE_TYPE (olddecl)) != 0);
1590 bool extern_changed = false;
1592 /* For real parm decl following a forward decl, rechain the old decl
1593 in its new location and clear TREE_ASM_WRITTEN (it's not a
1594 forward decl anymore). */
1595 if (TREE_CODE (newdecl) == PARM_DECL
1596 && TREE_ASM_WRITTEN (olddecl) && !TREE_ASM_WRITTEN (newdecl))
1598 struct c_binding *b, **here;
1600 for (here = ¤t_scope->bindings; *here; here = &(*here)->prev)
1601 if ((*here)->decl == olddecl)
1608 b->prev = current_scope->bindings;
1609 current_scope->bindings = b;
1611 TREE_ASM_WRITTEN (olddecl) = 0;
1614 DECL_ATTRIBUTES (newdecl)
1615 = targetm.merge_decl_attributes (olddecl, newdecl);
1617 /* Merge the data types specified in the two decls. */
1619 = TREE_TYPE (olddecl)
1620 = composite_type (newtype, oldtype);
1622 /* Lay the type out, unless already done. */
1623 if (!comptypes (oldtype, TREE_TYPE (newdecl)))
1625 if (TREE_TYPE (newdecl) != error_mark_node)
1626 layout_type (TREE_TYPE (newdecl));
1627 if (TREE_CODE (newdecl) != FUNCTION_DECL
1628 && TREE_CODE (newdecl) != TYPE_DECL
1629 && TREE_CODE (newdecl) != CONST_DECL)
1630 layout_decl (newdecl, 0);
1634 /* Since the type is OLDDECL's, make OLDDECL's size go with. */
1635 DECL_SIZE (newdecl) = DECL_SIZE (olddecl);
1636 DECL_SIZE_UNIT (newdecl) = DECL_SIZE_UNIT (olddecl);
1637 DECL_MODE (newdecl) = DECL_MODE (olddecl);
1638 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
1640 DECL_ALIGN (newdecl) = DECL_ALIGN (olddecl);
1641 DECL_USER_ALIGN (newdecl) |= DECL_USER_ALIGN (olddecl);
1645 /* Keep the old rtl since we can safely use it. */
1646 if (HAS_RTL_P (olddecl))
1647 COPY_DECL_RTL (olddecl, newdecl);
1649 /* Merge the type qualifiers. */
1650 if (TREE_READONLY (newdecl))
1651 TREE_READONLY (olddecl) = 1;
1653 if (TREE_THIS_VOLATILE (newdecl))
1654 TREE_THIS_VOLATILE (olddecl) = 1;
1656 /* Merge deprecatedness. */
1657 if (TREE_DEPRECATED (newdecl))
1658 TREE_DEPRECATED (olddecl) = 1;
1660 /* If a decl is in a system header and the other isn't, keep the one on the
1661 system header. Otherwise, keep source location of definition rather than
1662 declaration and of prototype rather than non-prototype unless that
1663 prototype is built-in. */
1664 if (CODE_CONTAINS_STRUCT (TREE_CODE (olddecl), TS_DECL_WITH_VIS)
1665 && DECL_IN_SYSTEM_HEADER (olddecl)
1666 && !DECL_IN_SYSTEM_HEADER (newdecl) )
1667 DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
1668 else if (CODE_CONTAINS_STRUCT (TREE_CODE (olddecl), TS_DECL_WITH_VIS)
1669 && DECL_IN_SYSTEM_HEADER (newdecl)
1670 && !DECL_IN_SYSTEM_HEADER (olddecl))
1671 DECL_SOURCE_LOCATION (olddecl) = DECL_SOURCE_LOCATION (newdecl);
1672 else if ((DECL_INITIAL (newdecl) == 0 && DECL_INITIAL (olddecl) != 0)
1673 || (old_is_prototype && !new_is_prototype
1674 && !C_DECL_BUILTIN_PROTOTYPE (olddecl)))
1675 DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
1677 /* Merge the initialization information. */
1678 if (DECL_INITIAL (newdecl) == 0)
1679 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1681 /* Merge the threadprivate attribute. */
1682 if (TREE_CODE (olddecl) == VAR_DECL && C_DECL_THREADPRIVATE_P (olddecl))
1684 DECL_TLS_MODEL (newdecl) = DECL_TLS_MODEL (olddecl);
1685 C_DECL_THREADPRIVATE_P (newdecl) = 1;
1688 if (CODE_CONTAINS_STRUCT (TREE_CODE (olddecl), TS_DECL_WITH_VIS))
1690 /* Merge the section attribute.
1691 We want to issue an error if the sections conflict but that
1692 must be done later in decl_attributes since we are called
1693 before attributes are assigned. */
1694 if (DECL_SECTION_NAME (newdecl) == NULL_TREE)
1695 DECL_SECTION_NAME (newdecl) = DECL_SECTION_NAME (olddecl);
1697 /* Copy the assembler name.
1698 Currently, it can only be defined in the prototype. */
1699 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
1701 /* Use visibility of whichever declaration had it specified */
1702 if (DECL_VISIBILITY_SPECIFIED (olddecl))
1704 DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
1705 DECL_VISIBILITY_SPECIFIED (newdecl) = 1;
1708 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1710 DECL_STATIC_CONSTRUCTOR(newdecl) |= DECL_STATIC_CONSTRUCTOR(olddecl);
1711 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1712 DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
1713 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
1714 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
1715 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1716 DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
1717 DECL_IS_OPERATOR_NEW (newdecl) |= DECL_IS_OPERATOR_NEW (olddecl);
1718 TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
1719 DECL_PURE_P (newdecl) |= DECL_PURE_P (olddecl);
1720 DECL_IS_NOVOPS (newdecl) |= DECL_IS_NOVOPS (olddecl);
1723 /* Merge the storage class information. */
1724 merge_weak (newdecl, olddecl);
1726 /* For functions, static overrides non-static. */
1727 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1729 TREE_PUBLIC (newdecl) &= TREE_PUBLIC (olddecl);
1730 /* This is since we don't automatically
1731 copy the attributes of NEWDECL into OLDDECL. */
1732 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1733 /* If this clears `static', clear it in the identifier too. */
1734 if (!TREE_PUBLIC (olddecl))
1735 TREE_PUBLIC (DECL_NAME (olddecl)) = 0;
1739 /* In c99, 'extern' declaration before (or after) 'inline' means this
1740 function is not DECL_EXTERNAL, unless 'gnu_inline' attribute
1742 if (TREE_CODE (newdecl) == FUNCTION_DECL
1743 && !flag_gnu89_inline
1744 && (DECL_DECLARED_INLINE_P (newdecl)
1745 || DECL_DECLARED_INLINE_P (olddecl))
1746 && (!DECL_DECLARED_INLINE_P (newdecl)
1747 || !DECL_DECLARED_INLINE_P (olddecl)
1748 || !DECL_EXTERNAL (olddecl))
1749 && DECL_EXTERNAL (newdecl)
1750 && !lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (newdecl))
1751 && !current_function_decl)
1752 DECL_EXTERNAL (newdecl) = 0;
1754 if (DECL_EXTERNAL (newdecl))
1756 TREE_STATIC (newdecl) = TREE_STATIC (olddecl);
1757 DECL_EXTERNAL (newdecl) = DECL_EXTERNAL (olddecl);
1759 /* An extern decl does not override previous storage class. */
1760 TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
1761 if (!DECL_EXTERNAL (newdecl))
1763 DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
1764 DECL_COMMON (newdecl) = DECL_COMMON (olddecl);
1769 TREE_STATIC (olddecl) = TREE_STATIC (newdecl);
1770 TREE_PUBLIC (olddecl) = TREE_PUBLIC (newdecl);
1773 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1775 /* If we're redefining a function previously defined as extern
1776 inline, make sure we emit debug info for the inline before we
1777 throw it away, in case it was inlined into a function that
1778 hasn't been written out yet. */
1779 if (new_is_definition && DECL_INITIAL (olddecl))
1781 if (TREE_USED (olddecl)
1782 /* We never inline re-defined extern inline functions.
1783 FIXME: This would be better handled by keeping both functions
1784 as separate declarations. */
1785 && cgraph_function_possibly_inlined_p (olddecl))
1786 (*debug_hooks->outlining_inline_function) (olddecl);
1788 /* The new defn must not be inline. */
1789 DECL_UNINLINABLE (newdecl) = 1;
1793 /* If either decl says `inline', this fn is inline, unless
1794 its definition was passed already. */
1795 if (DECL_DECLARED_INLINE_P (newdecl)
1796 || DECL_DECLARED_INLINE_P (olddecl))
1797 DECL_DECLARED_INLINE_P (newdecl) = 1;
1799 DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
1800 = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
1802 DECL_DISREGARD_INLINE_LIMITS (newdecl)
1803 = DECL_DISREGARD_INLINE_LIMITS (olddecl)
1804 = (DECL_DISREGARD_INLINE_LIMITS (newdecl)
1805 || DECL_DISREGARD_INLINE_LIMITS (olddecl));
1808 if (DECL_BUILT_IN (olddecl))
1810 /* If redeclaring a builtin function, it stays built in.
1811 But it gets tagged as having been declared. */
1812 DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
1813 DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
1814 C_DECL_DECLARED_BUILTIN (newdecl) = 1;
1815 if (new_is_prototype)
1816 C_DECL_BUILTIN_PROTOTYPE (newdecl) = 0;
1818 C_DECL_BUILTIN_PROTOTYPE (newdecl)
1819 = C_DECL_BUILTIN_PROTOTYPE (olddecl);
1822 /* Preserve function specific target and optimization options */
1823 if (DECL_FUNCTION_SPECIFIC_TARGET (olddecl)
1824 && !DECL_FUNCTION_SPECIFIC_TARGET (newdecl))
1825 DECL_FUNCTION_SPECIFIC_TARGET (newdecl)
1826 = DECL_FUNCTION_SPECIFIC_TARGET (olddecl);
1828 if (DECL_FUNCTION_SPECIFIC_OPTIMIZATION (olddecl)
1829 && !DECL_FUNCTION_SPECIFIC_OPTIMIZATION (newdecl))
1830 DECL_FUNCTION_SPECIFIC_OPTIMIZATION (newdecl)
1831 = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (olddecl);
1833 /* Also preserve various other info from the definition. */
1834 if (!new_is_definition)
1836 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
1837 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
1838 DECL_STRUCT_FUNCTION (newdecl) = DECL_STRUCT_FUNCTION (olddecl);
1839 DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
1840 gimple_set_body (newdecl, gimple_body (olddecl));
1841 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
1843 /* See if we've got a function to instantiate from. */
1844 if (DECL_SAVED_TREE (olddecl))
1845 DECL_ABSTRACT_ORIGIN (newdecl)
1846 = DECL_ABSTRACT_ORIGIN (olddecl);
1850 extern_changed = DECL_EXTERNAL (olddecl) && !DECL_EXTERNAL (newdecl);
1852 /* Merge the USED information. */
1853 if (TREE_USED (olddecl))
1854 TREE_USED (newdecl) = 1;
1855 else if (TREE_USED (newdecl))
1856 TREE_USED (olddecl) = 1;
1858 /* Copy most of the decl-specific fields of NEWDECL into OLDDECL.
1859 But preserve OLDDECL's DECL_UID and DECL_CONTEXT. */
1861 unsigned olddecl_uid = DECL_UID (olddecl);
1862 tree olddecl_context = DECL_CONTEXT (olddecl);
1864 memcpy ((char *) olddecl + sizeof (struct tree_common),
1865 (char *) newdecl + sizeof (struct tree_common),
1866 sizeof (struct tree_decl_common) - sizeof (struct tree_common));
1867 switch (TREE_CODE (olddecl))
1870 gimple_set_body (olddecl, gimple_body (newdecl));
1880 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1881 (char *) newdecl + sizeof (struct tree_decl_common),
1882 tree_code_size (TREE_CODE (olddecl)) - sizeof (struct tree_decl_common));
1887 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
1888 (char *) newdecl + sizeof (struct tree_decl_common),
1889 sizeof (struct tree_decl_non_common) - sizeof (struct tree_decl_common));
1891 DECL_UID (olddecl) = olddecl_uid;
1892 DECL_CONTEXT (olddecl) = olddecl_context;
1895 /* If OLDDECL had its DECL_RTL instantiated, re-invoke make_decl_rtl
1896 so that encode_section_info has a chance to look at the new decl
1897 flags and attributes. */
1898 if (DECL_RTL_SET_P (olddecl)
1899 && (TREE_CODE (olddecl) == FUNCTION_DECL
1900 || (TREE_CODE (olddecl) == VAR_DECL
1901 && TREE_STATIC (olddecl))))
1902 make_decl_rtl (olddecl);
1904 /* If we changed a function from DECL_EXTERNAL to !DECL_EXTERNAL,
1905 and the definition is coming from the old version, cgraph needs
1906 to be called again. */
1907 if (extern_changed && !new_is_definition
1908 && TREE_CODE (olddecl) == FUNCTION_DECL && DECL_INITIAL (olddecl))
1909 cgraph_mark_if_needed (olddecl);
1912 /* Handle when a new declaration NEWDECL has the same name as an old
1913 one OLDDECL in the same binding contour. Prints an error message
1916 If safely possible, alter OLDDECL to look like NEWDECL, and return
1917 true. Otherwise, return false. */
1920 duplicate_decls (tree newdecl, tree olddecl)
1922 tree newtype = NULL, oldtype = NULL;
1924 if (!diagnose_mismatched_decls (newdecl, olddecl, &newtype, &oldtype))
1926 /* Avoid `unused variable' and other warnings for OLDDECL. */
1927 TREE_NO_WARNING (olddecl) = 1;
1931 merge_decls (newdecl, olddecl, newtype, oldtype);
1936 /* Check whether decl-node NEW_DECL shadows an existing declaration. */
1938 warn_if_shadowing (tree new_decl)
1940 struct c_binding *b;
1942 /* Shadow warnings wanted? */
1944 /* No shadow warnings for internally generated vars. */
1945 || DECL_IS_BUILTIN (new_decl)
1946 /* No shadow warnings for vars made for inlining. */
1947 || DECL_FROM_INLINE (new_decl))
1950 /* Is anything being shadowed? Invisible decls do not count. */
1951 for (b = I_SYMBOL_BINDING (DECL_NAME (new_decl)); b; b = b->shadowed)
1952 if (b->decl && b->decl != new_decl && !b->invisible)
1954 tree old_decl = b->decl;
1956 if (old_decl == error_mark_node)
1958 warning (OPT_Wshadow, "declaration of %q+D shadows previous "
1959 "non-variable", new_decl);
1962 else if (TREE_CODE (old_decl) == PARM_DECL)
1963 warning (OPT_Wshadow, "declaration of %q+D shadows a parameter",
1965 else if (DECL_FILE_SCOPE_P (old_decl))
1966 warning (OPT_Wshadow, "declaration of %q+D shadows a global "
1967 "declaration", new_decl);
1968 else if (TREE_CODE (old_decl) == FUNCTION_DECL
1969 && DECL_BUILT_IN (old_decl))
1971 warning (OPT_Wshadow, "declaration of %q+D shadows "
1972 "a built-in function", new_decl);
1976 warning (OPT_Wshadow, "declaration of %q+D shadows a previous local",
1979 warning (OPT_Wshadow, "%Jshadowed declaration is here", old_decl);
1986 /* Subroutine of pushdecl.
1988 X is a TYPE_DECL for a typedef statement. Create a brand new
1989 ..._TYPE node (which will be just a variant of the existing
1990 ..._TYPE node with identical properties) and then install X
1991 as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
1993 The whole point here is to end up with a situation where each
1994 and every ..._TYPE node the compiler creates will be uniquely
1995 associated with AT MOST one node representing a typedef name.
1996 This way, even though the compiler substitutes corresponding
1997 ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
1998 early on, later parts of the compiler can always do the reverse
1999 translation and get back the corresponding typedef name. For
2002 typedef struct S MY_TYPE;
2005 Later parts of the compiler might only know that `object' was of
2006 type `struct S' if it were not for code just below. With this
2007 code however, later parts of the compiler see something like:
2009 struct S' == struct S
2010 typedef struct S' MY_TYPE;
2013 And they can then deduce (from the node for type struct S') that
2014 the original object declaration was:
2018 Being able to do this is important for proper support of protoize,
2019 and also for generating precise symbolic debugging information
2020 which takes full account of the programmer's (typedef) vocabulary.
2022 Obviously, we don't want to generate a duplicate ..._TYPE node if
2023 the TYPE_DECL node that we are now processing really represents a
2024 standard built-in type. */
2027 clone_underlying_type (tree x)
2029 if (DECL_IS_BUILTIN (x))
2031 if (TYPE_NAME (TREE_TYPE (x)) == 0)
2032 TYPE_NAME (TREE_TYPE (x)) = x;
2034 else if (TREE_TYPE (x) != error_mark_node
2035 && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
2037 tree tt = TREE_TYPE (x);
2038 DECL_ORIGINAL_TYPE (x) = tt;
2039 tt = build_variant_type_copy (tt);
2041 TREE_USED (tt) = TREE_USED (x);
2046 /* Record a decl-node X as belonging to the current lexical scope.
2047 Check for errors (such as an incompatible declaration for the same
2048 name already seen in the same scope).
2050 Returns either X or an old decl for the same name.
2051 If an old decl is returned, it may have been smashed
2052 to agree with what X says. */
2057 tree name = DECL_NAME (x);
2058 struct c_scope *scope = current_scope;
2059 struct c_binding *b;
2060 bool nested = false;
2062 /* Must set DECL_CONTEXT for everything not at file scope or
2063 DECL_FILE_SCOPE_P won't work. Local externs don't count
2064 unless they have initializers (which generate code). */
2065 if (current_function_decl
2066 && ((TREE_CODE (x) != FUNCTION_DECL && TREE_CODE (x) != VAR_DECL)
2067 || DECL_INITIAL (x) || !DECL_EXTERNAL (x)))
2068 DECL_CONTEXT (x) = current_function_decl;
2070 /* If this is of variably modified type, prevent jumping into its
2072 if ((TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == TYPE_DECL)
2073 && variably_modified_type_p (TREE_TYPE (x), NULL_TREE))
2074 c_begin_vm_scope (scope->depth);
2076 /* Anonymous decls are just inserted in the scope. */
2079 bind (name, x, scope, /*invisible=*/false, /*nested=*/false);
2083 /* First, see if there is another declaration with the same name in
2084 the current scope. If there is, duplicate_decls may do all the
2085 work for us. If duplicate_decls returns false, that indicates
2086 two incompatible decls in the same scope; we are to silently
2087 replace the old one (duplicate_decls has issued all appropriate
2088 diagnostics). In particular, we should not consider possible
2089 duplicates in the external scope, or shadowing. */
2090 b = I_SYMBOL_BINDING (name);
2091 if (b && B_IN_SCOPE (b, scope))
2093 struct c_binding *b_ext, *b_use;
2094 tree type = TREE_TYPE (x);
2095 tree visdecl = b->decl;
2096 tree vistype = TREE_TYPE (visdecl);
2097 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
2098 && COMPLETE_TYPE_P (TREE_TYPE (x)))
2099 b->inner_comp = false;
2102 /* If this is an external linkage declaration, we should check
2103 for compatibility with the type in the external scope before
2104 setting the type at this scope based on the visible
2105 information only. */
2106 if (TREE_PUBLIC (x) && TREE_PUBLIC (visdecl))
2108 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
2109 b_ext = b_ext->shadowed;
2114 TREE_TYPE (b_use->decl) = b_use->type;
2117 if (duplicate_decls (x, b_use->decl))
2121 /* Save the updated type in the external scope and
2122 restore the proper type for this scope. */
2124 if (comptypes (vistype, type))
2125 thistype = composite_type (vistype, type);
2127 thistype = TREE_TYPE (b_use->decl);
2128 b_use->type = TREE_TYPE (b_use->decl);
2129 if (TREE_CODE (b_use->decl) == FUNCTION_DECL
2130 && DECL_BUILT_IN (b_use->decl))
2132 = build_type_attribute_variant (thistype,
2135 TREE_TYPE (b_use->decl) = thistype;
2140 goto skip_external_and_shadow_checks;
2143 /* All declarations with external linkage, and all external
2144 references, go in the external scope, no matter what scope is
2145 current. However, the binding in that scope is ignored for
2146 purposes of normal name lookup. A separate binding structure is
2147 created in the requested scope; this governs the normal
2148 visibility of the symbol.
2150 The binding in the externals scope is used exclusively for
2151 detecting duplicate declarations of the same object, no matter
2152 what scope they are in; this is what we do here. (C99 6.2.7p2:
2153 All declarations that refer to the same object or function shall
2154 have compatible type; otherwise, the behavior is undefined.) */
2155 if (DECL_EXTERNAL (x) || scope == file_scope)
2157 tree type = TREE_TYPE (x);
2160 bool type_saved = false;
2161 if (b && !B_IN_EXTERNAL_SCOPE (b)
2162 && (TREE_CODE (b->decl) == FUNCTION_DECL
2163 || TREE_CODE (b->decl) == VAR_DECL)
2164 && DECL_FILE_SCOPE_P (b->decl))
2167 vistype = TREE_TYPE (visdecl);
2169 if (scope != file_scope
2170 && !DECL_IN_SYSTEM_HEADER (x))
2171 warning (OPT_Wnested_externs, "nested extern declaration of %qD", x);
2173 while (b && !B_IN_EXTERNAL_SCOPE (b))
2175 /* If this decl might be modified, save its type. This is
2176 done here rather than when the decl is first bound
2177 because the type may change after first binding, through
2178 being completed or through attributes being added. If we
2179 encounter multiple such decls, only the first should have
2180 its type saved; the others will already have had their
2181 proper types saved and the types will not have changed as
2182 their scopes will not have been re-entered. */
2183 if (DECL_P (b->decl) && DECL_FILE_SCOPE_P (b->decl) && !type_saved)
2185 b->type = TREE_TYPE (b->decl);
2188 if (B_IN_FILE_SCOPE (b)
2189 && TREE_CODE (b->decl) == VAR_DECL
2190 && TREE_STATIC (b->decl)
2191 && TREE_CODE (TREE_TYPE (b->decl)) == ARRAY_TYPE
2192 && !TYPE_DOMAIN (TREE_TYPE (b->decl))
2193 && TREE_CODE (type) == ARRAY_TYPE
2194 && TYPE_DOMAIN (type)
2195 && TYPE_MAX_VALUE (TYPE_DOMAIN (type))
2196 && !integer_zerop (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
2198 /* Array type completed in inner scope, which should be
2199 diagnosed if the completion does not have size 1 and
2200 it does not get completed in the file scope. */
2201 b->inner_comp = true;
2206 /* If a matching external declaration has been found, set its
2207 type to the composite of all the types of that declaration.
2208 After the consistency checks, it will be reset to the
2209 composite of the visible types only. */
2210 if (b && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2212 TREE_TYPE (b->decl) = b->type;
2214 /* The point of the same_translation_unit_p check here is,
2215 we want to detect a duplicate decl for a construct like
2216 foo() { extern bar(); } ... static bar(); but not if
2217 they are in different translation units. In any case,
2218 the static does not go in the externals scope. */
2220 && (TREE_PUBLIC (x) || same_translation_unit_p (x, b->decl))
2221 && duplicate_decls (x, b->decl))
2226 if (comptypes (vistype, type))
2227 thistype = composite_type (vistype, type);
2229 thistype = TREE_TYPE (b->decl);
2233 b->type = TREE_TYPE (b->decl);
2234 if (TREE_CODE (b->decl) == FUNCTION_DECL && DECL_BUILT_IN (b->decl))
2236 = build_type_attribute_variant (thistype,
2237 TYPE_ATTRIBUTES (b->type));
2238 TREE_TYPE (b->decl) = thistype;
2239 bind (name, b->decl, scope, /*invisible=*/false, /*nested=*/true);
2242 else if (TREE_PUBLIC (x))
2244 if (visdecl && !b && duplicate_decls (x, visdecl))
2246 /* An external declaration at block scope referring to a
2247 visible entity with internal linkage. The composite
2248 type will already be correct for this scope, so we
2249 just need to fall through to make the declaration in
2256 bind (name, x, external_scope, /*invisible=*/true,
2263 if (TREE_CODE (x) != PARM_DECL)
2264 warn_if_shadowing (x);
2266 skip_external_and_shadow_checks:
2267 if (TREE_CODE (x) == TYPE_DECL)
2268 clone_underlying_type (x);
2270 bind (name, x, scope, /*invisible=*/false, nested);
2272 /* If x's type is incomplete because it's based on a
2273 structure or union which has not yet been fully declared,
2274 attach it to that structure or union type, so we can go
2275 back and complete the variable declaration later, if the
2276 structure or union gets fully declared.
2278 If the input is erroneous, we can have error_mark in the type
2279 slot (e.g. "f(void a, ...)") - that doesn't count as an
2281 if (TREE_TYPE (x) != error_mark_node
2282 && !COMPLETE_TYPE_P (TREE_TYPE (x)))
2284 tree element = TREE_TYPE (x);
2286 while (TREE_CODE (element) == ARRAY_TYPE)
2287 element = TREE_TYPE (element);
2288 element = TYPE_MAIN_VARIANT (element);
2290 if ((TREE_CODE (element) == RECORD_TYPE
2291 || TREE_CODE (element) == UNION_TYPE)
2292 && (TREE_CODE (x) != TYPE_DECL
2293 || TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE)
2294 && !COMPLETE_TYPE_P (element))
2295 C_TYPE_INCOMPLETE_VARS (element)
2296 = tree_cons (NULL_TREE, x, C_TYPE_INCOMPLETE_VARS (element));
2301 /* Record X as belonging to file scope.
2302 This is used only internally by the Objective-C front end,
2303 and is limited to its needs. duplicate_decls is not called;
2304 if there is any preexisting decl for this identifier, it is an ICE. */
2307 pushdecl_top_level (tree x)
2310 bool nested = false;
2311 gcc_assert (TREE_CODE (x) == VAR_DECL || TREE_CODE (x) == CONST_DECL);
2313 name = DECL_NAME (x);
2315 gcc_assert (TREE_CODE (x) == CONST_DECL || !I_SYMBOL_BINDING (name));
2317 if (TREE_PUBLIC (x))
2319 bind (name, x, external_scope, /*invisible=*/true, /*nested=*/false);
2323 bind (name, x, file_scope, /*invisible=*/false, nested);
2329 implicit_decl_warning (tree id, tree olddecl)
2331 if (warn_implicit_function_declaration)
2334 pedwarn (OPT_Wimplicit_function_declaration,
2335 G_("implicit declaration of function %qE"), id);
2337 warning (OPT_Wimplicit_function_declaration,
2338 G_("implicit declaration of function %qE"), id);
2340 locate_old_decl (olddecl, inform);
2344 /* Generate an implicit declaration for identifier FUNCTIONID as a
2345 function of type int (). */
2348 implicitly_declare (tree functionid)
2350 struct c_binding *b;
2354 for (b = I_SYMBOL_BINDING (functionid); b; b = b->shadowed)
2356 if (B_IN_SCOPE (b, external_scope))
2365 if (decl == error_mark_node)
2368 /* FIXME: Objective-C has weird not-really-builtin functions
2369 which are supposed to be visible automatically. They wind up
2370 in the external scope because they're pushed before the file
2371 scope gets created. Catch this here and rebind them into the
2373 if (!DECL_BUILT_IN (decl) && DECL_IS_BUILTIN (decl))
2375 bind (functionid, decl, file_scope,
2376 /*invisible=*/false, /*nested=*/true);
2381 tree newtype = default_function_type;
2383 TREE_TYPE (decl) = b->type;
2384 /* Implicit declaration of a function already declared
2385 (somehow) in a different scope, or as a built-in.
2386 If this is the first time this has happened, warn;
2387 then recycle the old declaration but with the new type. */
2388 if (!C_DECL_IMPLICIT (decl))
2390 implicit_decl_warning (functionid, decl);
2391 C_DECL_IMPLICIT (decl) = 1;
2393 if (DECL_BUILT_IN (decl))
2395 newtype = build_type_attribute_variant (newtype,
2397 (TREE_TYPE (decl)));
2398 if (!comptypes (newtype, TREE_TYPE (decl)))
2400 warning (0, "incompatible implicit declaration of built-in"
2401 " function %qD", decl);
2402 newtype = TREE_TYPE (decl);
2407 if (!comptypes (newtype, TREE_TYPE (decl)))
2409 error ("incompatible implicit declaration of function %qD",
2411 locate_old_decl (decl, error);
2414 b->type = TREE_TYPE (decl);
2415 TREE_TYPE (decl) = newtype;
2416 bind (functionid, decl, current_scope,
2417 /*invisible=*/false, /*nested=*/true);
2422 /* Not seen before. */
2423 decl = build_decl (FUNCTION_DECL, functionid, default_function_type);
2424 DECL_EXTERNAL (decl) = 1;
2425 TREE_PUBLIC (decl) = 1;
2426 C_DECL_IMPLICIT (decl) = 1;
2427 implicit_decl_warning (functionid, 0);
2428 asmspec_tree = maybe_apply_renaming_pragma (decl, /*asmname=*/NULL);
2430 set_user_assembler_name (decl, TREE_STRING_POINTER (asmspec_tree));
2432 /* C89 says implicit declarations are in the innermost block.
2433 So we record the decl in the standard fashion. */
2434 decl = pushdecl (decl);
2436 /* No need to call objc_check_decl here - it's a function type. */
2437 rest_of_decl_compilation (decl, 0, 0);
2439 /* Write a record describing this implicit function declaration
2440 to the prototypes file (if requested). */
2441 gen_aux_info_record (decl, 0, 1, 0);
2443 /* Possibly apply some default attributes to this implicit declaration. */
2444 decl_attributes (&decl, NULL_TREE, 0);
2449 /* Issue an error message for a reference to an undeclared variable
2450 ID, including a reference to a builtin outside of function-call
2451 context. Establish a binding of the identifier to error_mark_node
2452 in an appropriate scope, which will suppress further errors for the
2453 same identifier. The error message should be given location LOC. */
2455 undeclared_variable (tree id, location_t loc)
2457 static bool already = false;
2458 struct c_scope *scope;
2460 if (current_function_decl == 0)
2462 error ("%H%qE undeclared here (not in a function)", &loc, id);
2463 scope = current_scope;
2467 error ("%H%qE undeclared (first use in this function)", &loc, id);
2471 error ("%H(Each undeclared identifier is reported only once", &loc);
2472 error ("%Hfor each function it appears in.)", &loc);
2476 /* If we are parsing old-style parameter decls, current_function_decl
2477 will be nonnull but current_function_scope will be null. */
2478 scope = current_function_scope ? current_function_scope : current_scope;
2480 bind (id, error_mark_node, scope, /*invisible=*/false, /*nested=*/false);
2483 /* Subroutine of lookup_label, declare_label, define_label: construct a
2484 LABEL_DECL with all the proper frills. */
2487 make_label (tree name, location_t location)
2489 tree label = build_decl (LABEL_DECL, name, void_type_node);
2491 DECL_CONTEXT (label) = current_function_decl;
2492 DECL_MODE (label) = VOIDmode;
2493 DECL_SOURCE_LOCATION (label) = location;
2498 /* Get the LABEL_DECL corresponding to identifier NAME as a label.
2499 Create one if none exists so far for the current function.
2500 This is called when a label is used in a goto expression or
2501 has its address taken. */
2504 lookup_label (tree name)
2508 if (current_function_decl == 0)
2510 error ("label %qE referenced outside of any function", name);
2514 /* Use a label already defined or ref'd with this name, but not if
2515 it is inherited from a containing function and wasn't declared
2517 label = I_LABEL_DECL (name);
2518 if (label && (DECL_CONTEXT (label) == current_function_decl
2519 || C_DECLARED_LABEL_FLAG (label)))
2521 /* If the label has only been declared, update its apparent
2522 location to point here, for better diagnostics if it
2523 turns out not to have been defined. */
2524 if (!TREE_USED (label))
2525 DECL_SOURCE_LOCATION (label) = input_location;
2529 /* No label binding for that identifier; make one. */
2530 label = make_label (name, input_location);
2532 /* Ordinary labels go in the current function scope. */
2533 bind (name, label, current_function_scope,
2534 /*invisible=*/false, /*nested=*/false);
2538 /* Make a label named NAME in the current function, shadowing silently
2539 any that may be inherited from containing functions or containing
2540 scopes. This is called for __label__ declarations. */
2543 declare_label (tree name)
2545 struct c_binding *b = I_LABEL_BINDING (name);
2548 /* Check to make sure that the label hasn't already been declared
2550 if (b && B_IN_CURRENT_SCOPE (b))
2552 error ("duplicate label declaration %qE", name);
2553 locate_old_decl (b->decl, error);
2555 /* Just use the previous declaration. */
2559 label = make_label (name, input_location);
2560 C_DECLARED_LABEL_FLAG (label) = 1;
2562 /* Declared labels go in the current scope. */
2563 bind (name, label, current_scope,
2564 /*invisible=*/false, /*nested=*/false);
2568 /* Define a label, specifying the location in the source file.
2569 Return the LABEL_DECL node for the label, if the definition is valid.
2570 Otherwise return 0. */
2573 define_label (location_t location, tree name)
2575 /* Find any preexisting label with this name. It is an error
2576 if that label has already been defined in this function, or
2577 if there is a containing function with a declared label with
2579 tree label = I_LABEL_DECL (name);
2580 struct c_label_list *nlist_se, *nlist_vm;
2583 && ((DECL_CONTEXT (label) == current_function_decl
2584 && DECL_INITIAL (label) != 0)
2585 || (DECL_CONTEXT (label) != current_function_decl
2586 && C_DECLARED_LABEL_FLAG (label))))
2588 error ("%Hduplicate label %qD", &location, label);
2589 locate_old_decl (label, error);
2592 else if (label && DECL_CONTEXT (label) == current_function_decl)
2594 /* The label has been used or declared already in this function,
2595 but not defined. Update its location to point to this
2597 if (C_DECL_UNDEFINABLE_STMT_EXPR (label))
2598 error ("%Jjump into statement expression", label);
2599 if (C_DECL_UNDEFINABLE_VM (label))
2600 error ("%Jjump into scope of identifier with variably modified type",
2602 DECL_SOURCE_LOCATION (label) = location;
2606 /* No label binding for that identifier; make one. */
2607 label = make_label (name, location);
2609 /* Ordinary labels go in the current function scope. */
2610 bind (name, label, current_function_scope,
2611 /*invisible=*/false, /*nested=*/false);
2614 if (!in_system_header && lookup_name (name))
2615 warning (OPT_Wtraditional, "%Htraditional C lacks a separate namespace "
2616 "for labels, identifier %qE conflicts", &location, name);
2618 nlist_se = XOBNEW (&parser_obstack, struct c_label_list);
2619 nlist_se->next = label_context_stack_se->labels_def;
2620 nlist_se->label = label;
2621 label_context_stack_se->labels_def = nlist_se;
2623 nlist_vm = XOBNEW (&parser_obstack, struct c_label_list);
2624 nlist_vm->next = label_context_stack_vm->labels_def;
2625 nlist_vm->label = label;
2626 label_context_stack_vm->labels_def = nlist_vm;
2628 /* Mark label as having been defined. */
2629 DECL_INITIAL (label) = error_mark_node;
2633 /* Given NAME, an IDENTIFIER_NODE,
2634 return the structure (or union or enum) definition for that name.
2635 If THISLEVEL_ONLY is nonzero, searches only the current_scope.
2636 CODE says which kind of type the caller wants;
2637 it is RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE.
2638 If the wrong kind of type is found, an error is reported. */
2641 lookup_tag (enum tree_code code, tree name, int thislevel_only)
2643 struct c_binding *b = I_TAG_BINDING (name);
2649 /* We only care about whether it's in this level if
2650 thislevel_only was set or it might be a type clash. */
2651 if (thislevel_only || TREE_CODE (b->decl) != code)
2653 /* For our purposes, a tag in the external scope is the same as
2654 a tag in the file scope. (Primarily relevant to Objective-C
2655 and its builtin structure tags, which get pushed before the
2656 file scope is created.) */
2657 if (B_IN_CURRENT_SCOPE (b)
2658 || (current_scope == file_scope && B_IN_EXTERNAL_SCOPE (b)))
2662 if (thislevel_only && !thislevel)
2665 if (TREE_CODE (b->decl) != code)
2667 /* Definition isn't the kind we were looking for. */
2668 pending_invalid_xref = name;
2669 pending_invalid_xref_location = input_location;
2671 /* If in the same binding level as a declaration as a tag
2672 of a different type, this must not be allowed to
2673 shadow that tag, so give the error immediately.
2674 (For example, "struct foo; union foo;" is invalid.) */
2676 pending_xref_error ();
2681 /* Print an error message now
2682 for a recent invalid struct, union or enum cross reference.
2683 We don't print them immediately because they are not invalid
2684 when used in the `struct foo;' construct for shadowing. */
2687 pending_xref_error (void)
2689 if (pending_invalid_xref != 0)
2690 error ("%H%qE defined as wrong kind of tag",
2691 &pending_invalid_xref_location, pending_invalid_xref);
2692 pending_invalid_xref = 0;
2696 /* Look up NAME in the current scope and its superiors
2697 in the namespace of variables, functions and typedefs.
2698 Return a ..._DECL node of some kind representing its definition,
2699 or return 0 if it is undefined. */
2702 lookup_name (tree name)
2704 struct c_binding *b = I_SYMBOL_BINDING (name);
2705 if (b && !b->invisible)
2710 /* Similar to `lookup_name' but look only at the indicated scope. */
2713 lookup_name_in_scope (tree name, struct c_scope *scope)
2715 struct c_binding *b;
2717 for (b = I_SYMBOL_BINDING (name); b; b = b->shadowed)
2718 if (B_IN_SCOPE (b, scope))
2723 /* Create the predefined scalar types of C,
2724 and some nodes representing standard constants (0, 1, (void *) 0).
2725 Initialize the global scope.
2726 Make definitions for built-in primitive functions. */
2729 c_init_decl_processing (void)
2731 location_t save_loc = input_location;
2733 /* Initialize reserved words for parser. */
2736 current_function_decl = 0;
2738 gcc_obstack_init (&parser_obstack);
2740 /* Make the externals scope. */
2742 external_scope = current_scope;
2744 /* Declarations from c_common_nodes_and_builtins must not be associated
2745 with this input file, lest we get differences between using and not
2746 using preprocessed headers. */
2747 input_location = BUILTINS_LOCATION;
2749 build_common_tree_nodes (flag_signed_char, false);
2751 c_common_nodes_and_builtins ();
2753 /* In C, comparisons and TRUTH_* expressions have type int. */
2754 truthvalue_type_node = integer_type_node;
2755 truthvalue_true_node = integer_one_node;
2756 truthvalue_false_node = integer_zero_node;
2758 /* Even in C99, which has a real boolean type. */
2759 pushdecl (build_decl (TYPE_DECL, get_identifier ("_Bool"),
2760 boolean_type_node));
2762 input_location = save_loc;
2764 pedantic_lvalues = true;
2766 make_fname_decl = c_make_fname_decl;
2767 start_fname_decls ();
2770 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give the
2771 decl, NAME is the initialization string and TYPE_DEP indicates whether
2772 NAME depended on the type of the function. As we don't yet implement
2773 delayed emission of static data, we mark the decl as emitted
2774 so it is not placed in the output. Anything using it must therefore pull
2775 out the STRING_CST initializer directly. FIXME. */
2778 c_make_fname_decl (tree id, int type_dep)
2780 const char *name = fname_as_string (type_dep);
2781 tree decl, type, init;
2782 size_t length = strlen (name);
2784 type = build_array_type (char_type_node,
2785 build_index_type (size_int (length)));
2786 type = c_build_qualified_type (type, TYPE_QUAL_CONST);
2788 decl = build_decl (VAR_DECL, id, type);
2790 TREE_STATIC (decl) = 1;
2791 TREE_READONLY (decl) = 1;
2792 DECL_ARTIFICIAL (decl) = 1;
2794 init = build_string (length + 1, name);
2795 free (CONST_CAST (char *, name));
2796 TREE_TYPE (init) = type;
2797 DECL_INITIAL (decl) = init;
2799 TREE_USED (decl) = 1;
2801 if (current_function_decl
2802 /* For invalid programs like this:
2805 const char* p = __FUNCTION__;
2807 the __FUNCTION__ is believed to appear in K&R style function
2808 parameter declarator. In that case we still don't have
2810 && (!errorcount || current_function_scope))
2812 DECL_CONTEXT (decl) = current_function_decl;
2813 bind (id, decl, current_function_scope,
2814 /*invisible=*/false, /*nested=*/false);
2817 finish_decl (decl, init, NULL_TREE);
2823 c_builtin_function (tree decl)
2825 tree type = TREE_TYPE (decl);
2826 tree id = DECL_NAME (decl);
2828 const char *name = IDENTIFIER_POINTER (id);
2829 C_DECL_BUILTIN_PROTOTYPE (decl) = (TYPE_ARG_TYPES (type) != 0);
2831 /* Should never be called on a symbol with a preexisting meaning. */
2832 gcc_assert (!I_SYMBOL_BINDING (id));
2834 bind (id, decl, external_scope, /*invisible=*/true, /*nested=*/false);
2836 /* Builtins in the implementation namespace are made visible without
2837 needing to be explicitly declared. See push_file_scope. */
2838 if (name[0] == '_' && (name[1] == '_' || ISUPPER (name[1])))
2840 TREE_CHAIN (decl) = visible_builtins;
2841 visible_builtins = decl;
2847 /* Called when a declaration is seen that contains no names to declare.
2848 If its type is a reference to a structure, union or enum inherited
2849 from a containing scope, shadow that tag name for the current scope
2850 with a forward reference.
2851 If its type defines a new named structure or union
2852 or defines an enum, it is valid but we need not do anything here.
2853 Otherwise, it is an error. */
2856 shadow_tag (const struct c_declspecs *declspecs)
2858 shadow_tag_warned (declspecs, 0);
2861 /* WARNED is 1 if we have done a pedwarn, 2 if we have done a warning,
2864 shadow_tag_warned (const struct c_declspecs *declspecs, int warned)
2866 bool found_tag = false;
2868 if (declspecs->type && !declspecs->default_int_p && !declspecs->typedef_p)
2870 tree value = declspecs->type;
2871 enum tree_code code = TREE_CODE (value);
2873 if (code == RECORD_TYPE || code == UNION_TYPE || code == ENUMERAL_TYPE)
2874 /* Used to test also that TYPE_SIZE (value) != 0.
2875 That caused warning for `struct foo;' at top level in the file. */
2877 tree name = TYPE_NAME (value);
2884 if (warned != 1 && code != ENUMERAL_TYPE)
2885 /* Empty unnamed enum OK */
2887 pedwarn (0, "unnamed struct/union that defines no instances");
2891 else if (!declspecs->tag_defined_p
2892 && declspecs->storage_class != csc_none)
2895 pedwarn (0, "empty declaration with storage class specifier "
2896 "does not redeclare tag");
2898 pending_xref_error ();
2900 else if (!declspecs->tag_defined_p
2901 && (declspecs->const_p
2902 || declspecs->volatile_p
2903 || declspecs->restrict_p))
2906 pedwarn (0, "empty declaration with type qualifier "
2907 "does not redeclare tag");
2909 pending_xref_error ();
2913 pending_invalid_xref = 0;
2914 t = lookup_tag (code, name, 1);
2918 t = make_node (code);
2925 if (warned != 1 && !in_system_header)
2927 pedwarn (0, "useless type name in empty declaration");
2932 else if (warned != 1 && !in_system_header && declspecs->typedef_p)
2934 pedwarn (0, "useless type name in empty declaration");
2938 pending_invalid_xref = 0;
2940 if (declspecs->inline_p)
2942 error ("%<inline%> in empty declaration");
2946 if (current_scope == file_scope && declspecs->storage_class == csc_auto)
2948 error ("%<auto%> in file-scope empty declaration");
2952 if (current_scope == file_scope && declspecs->storage_class == csc_register)
2954 error ("%<register%> in file-scope empty declaration");
2958 if (!warned && !in_system_header && declspecs->storage_class != csc_none)
2960 warning (0, "useless storage class specifier in empty declaration");
2964 if (!warned && !in_system_header && declspecs->thread_p)
2966 warning (0, "useless %<__thread%> in empty declaration");
2970 if (!warned && !in_system_header && (declspecs->const_p
2971 || declspecs->volatile_p
2972 || declspecs->restrict_p))
2974 warning (0, "useless type qualifier in empty declaration");
2981 pedwarn (0, "empty declaration");
2986 /* Return the qualifiers from SPECS as a bitwise OR of TYPE_QUAL_*
2987 bits. SPECS represents declaration specifiers that the grammar
2988 only permits to contain type qualifiers and attributes. */
2991 quals_from_declspecs (const struct c_declspecs *specs)
2993 int quals = ((specs->const_p ? TYPE_QUAL_CONST : 0)
2994 | (specs->volatile_p ? TYPE_QUAL_VOLATILE : 0)
2995 | (specs->restrict_p ? TYPE_QUAL_RESTRICT : 0));
2996 gcc_assert (!specs->type
2997 && !specs->decl_attr
2998 && specs->typespec_word == cts_none
2999 && specs->storage_class == csc_none
3000 && !specs->typedef_p
3001 && !specs->explicit_signed_p
3002 && !specs->deprecated_p
3004 && !specs->long_long_p
3007 && !specs->unsigned_p
3008 && !specs->complex_p
3010 && !specs->thread_p);
3014 /* Construct an array declarator. EXPR is the expression inside [],
3015 or NULL_TREE. QUALS are the type qualifiers inside the [] (to be
3016 applied to the pointer to which a parameter array is converted).
3017 STATIC_P is true if "static" is inside the [], false otherwise.
3018 VLA_UNSPEC_P is true if the array is [*], a VLA of unspecified
3019 length which is nevertheless a complete type, false otherwise. The
3020 field for the contained declarator is left to be filled in by
3021 set_array_declarator_inner. */
3023 struct c_declarator *
3024 build_array_declarator (tree expr, struct c_declspecs *quals, bool static_p,
3027 struct c_declarator *declarator = XOBNEW (&parser_obstack,
3028 struct c_declarator);
3029 declarator->kind = cdk_array;
3030 declarator->declarator = 0;
3031 declarator->u.array.dimen = expr;
3034 declarator->u.array.attrs = quals->attrs;
3035 declarator->u.array.quals = quals_from_declspecs (quals);
3039 declarator->u.array.attrs = NULL_TREE;
3040 declarator->u.array.quals = 0;
3042 declarator->u.array.static_p = static_p;
3043 declarator->u.array.vla_unspec_p = vla_unspec_p;
3046 if (static_p || quals != NULL)
3047 pedwarn (OPT_pedantic, "ISO C90 does not support %<static%> or type "
3048 "qualifiers in parameter array declarators");
3050 pedwarn (OPT_pedantic, "ISO C90 does not support %<[*]%> array declarators");
3054 if (!current_scope->parm_flag)
3057 error ("%<[*]%> not allowed in other than function prototype scope");
3058 declarator->u.array.vla_unspec_p = false;
3061 current_scope->had_vla_unspec = true;
3066 /* Set the contained declarator of an array declarator. DECL is the
3067 declarator, as constructed by build_array_declarator; INNER is what
3068 appears on the left of the []. */
3070 struct c_declarator *
3071 set_array_declarator_inner (struct c_declarator *decl,
3072 struct c_declarator *inner)
3074 decl->declarator = inner;
3078 /* INIT is a constructor that forms DECL's initializer. If the final
3079 element initializes a flexible array field, add the size of that
3080 initializer to DECL's size. */
3083 add_flexible_array_elts_to_size (tree decl, tree init)
3087 if (VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (init)))
3090 elt = VEC_last (constructor_elt, CONSTRUCTOR_ELTS (init))->value;
3091 type = TREE_TYPE (elt);
3092 if (TREE_CODE (type) == ARRAY_TYPE
3093 && TYPE_SIZE (type) == NULL_TREE
3094 && TYPE_DOMAIN (type) != NULL_TREE
3095 && TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL_TREE)
3097 complete_array_type (&type, elt, false);
3099 = size_binop (PLUS_EXPR, DECL_SIZE (decl), TYPE_SIZE (type));
3100 DECL_SIZE_UNIT (decl)
3101 = size_binop (PLUS_EXPR, DECL_SIZE_UNIT (decl), TYPE_SIZE_UNIT (type));
3105 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
3108 groktypename (struct c_type_name *type_name)
3111 tree attrs = type_name->specs->attrs;
3113 type_name->specs->attrs = NULL_TREE;
3115 type = grokdeclarator (type_name->declarator, type_name->specs, TYPENAME,
3116 false, NULL, &attrs, DEPRECATED_NORMAL);
3118 /* Apply attributes. */
3119 decl_attributes (&type, attrs, 0);
3124 /* Decode a declarator in an ordinary declaration or data definition.
3125 This is called as soon as the type information and variable name
3126 have been parsed, before parsing the initializer if any.
3127 Here we create the ..._DECL node, fill in its type,
3128 and put it on the list of decls for the current context.
3129 The ..._DECL node is returned as the value.
3131 Exception: for arrays where the length is not specified,
3132 the type is left null, to be filled in by `finish_decl'.
3134 Function definitions do not come here; they go to start_function
3135 instead. However, external and forward declarations of functions
3136 do go through here. Structure field declarations are done by
3137 grokfield and not through here. */
3140 start_decl (struct c_declarator *declarator, struct c_declspecs *declspecs,
3141 bool initialized, tree attributes)
3145 enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
3147 /* An object declared as __attribute__((deprecated)) suppresses
3148 warnings of uses of other deprecated items. */
3149 if (lookup_attribute ("deprecated", attributes))
3150 deprecated_state = DEPRECATED_SUPPRESS;
3152 decl = grokdeclarator (declarator, declspecs,
3153 NORMAL, initialized, NULL, &attributes,
3158 if (warn_main > 0 && TREE_CODE (decl) != FUNCTION_DECL
3159 && MAIN_NAME_P (DECL_NAME (decl)))
3160 warning (OPT_Wmain, "%q+D is usually a function", decl);
3163 /* Is it valid for this decl to have an initializer at all?
3164 If not, set INITIALIZED to zero, which will indirectly
3165 tell 'finish_decl' to ignore the initializer once it is parsed. */
3166 switch (TREE_CODE (decl))
3169 error ("typedef %qD is initialized (use __typeof__ instead)", decl);
3174 error ("function %qD is initialized like a variable", decl);
3179 /* DECL_INITIAL in a PARM_DECL is really DECL_ARG_TYPE. */
3180 error ("parameter %qD is initialized", decl);
3185 /* Don't allow initializations for incomplete types except for
3186 arrays which might be completed by the initialization. */
3188 /* This can happen if the array size is an undefined macro.
3189 We already gave a warning, so we don't need another one. */
3190 if (TREE_TYPE (decl) == error_mark_node)
3192 else if (COMPLETE_TYPE_P (TREE_TYPE (decl)))
3194 /* A complete type is ok if size is fixed. */
3196 if (TREE_CODE (TYPE_SIZE (TREE_TYPE (decl))) != INTEGER_CST
3197 || C_DECL_VARIABLE_SIZE (decl))
3199 error ("variable-sized object may not be initialized");
3203 else if (TREE_CODE (TREE_TYPE (decl)) != ARRAY_TYPE)
3205 error ("variable %qD has initializer but incomplete type", decl);
3208 else if (C_DECL_VARIABLE_SIZE (decl))
3210 /* Although C99 is unclear about whether incomplete arrays
3211 of VLAs themselves count as VLAs, it does not make
3212 sense to permit them to be initialized given that
3213 ordinary VLAs may not be initialized. */
3214 error ("variable-sized object may not be initialized");
3221 if (current_scope == file_scope)
3222 TREE_STATIC (decl) = 1;
3224 /* Tell 'pushdecl' this is an initialized decl
3225 even though we don't yet have the initializer expression.
3226 Also tell 'finish_decl' it may store the real initializer. */
3227 DECL_INITIAL (decl) = error_mark_node;
3230 /* If this is a function declaration, write a record describing it to the
3231 prototypes file (if requested). */
3233 if (TREE_CODE (decl) == FUNCTION_DECL)
3234 gen_aux_info_record (decl, 0, 0, TYPE_ARG_TYPES (TREE_TYPE (decl)) != 0);
3236 /* ANSI specifies that a tentative definition which is not merged with
3237 a non-tentative definition behaves exactly like a definition with an
3238 initializer equal to zero. (Section 3.7.2)
3240 -fno-common gives strict ANSI behavior, though this tends to break
3241 a large body of code that grew up without this rule.
3243 Thread-local variables are never common, since there's no entrenched
3244 body of code to break, and it allows more efficient variable references
3245 in the presence of dynamic linking. */
3247 if (TREE_CODE (decl) == VAR_DECL
3249 && TREE_PUBLIC (decl)
3250 && !DECL_THREAD_LOCAL_P (decl)
3252 DECL_COMMON (decl) = 1;
3254 /* Set attributes here so if duplicate decl, will have proper attributes. */
3255 decl_attributes (&decl, attributes, 0);
3257 /* Handle gnu_inline attribute. */
3258 if (declspecs->inline_p
3259 && !flag_gnu89_inline
3260 && TREE_CODE (decl) == FUNCTION_DECL
3261 && (lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (decl))
3262 || current_function_decl))
3264 if (declspecs->storage_class == csc_auto && current_scope != file_scope)
3266 else if (declspecs->storage_class != csc_static)
3267 DECL_EXTERNAL (decl) = !DECL_EXTERNAL (decl);
3270 if (TREE_CODE (decl) == FUNCTION_DECL
3271 && targetm.calls.promote_prototypes (TREE_TYPE (decl)))
3273 struct c_declarator *ce = declarator;
3275 if (ce->kind == cdk_pointer)
3276 ce = declarator->declarator;
3277 if (ce->kind == cdk_function)
3279 tree args = ce->u.arg_info->parms;
3280 for (; args; args = TREE_CHAIN (args))
3282 tree type = TREE_TYPE (args);
3283 if (type && INTEGRAL_TYPE_P (type)
3284 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
3285 DECL_ARG_TYPE (args) = integer_type_node;
3290 if (TREE_CODE (decl) == FUNCTION_DECL
3291 && DECL_DECLARED_INLINE_P (decl)
3292 && DECL_UNINLINABLE (decl)
3293 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
3294 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
3297 /* C99 6.7.4p3: An inline definition of a function with external
3298 linkage shall not contain a definition of a modifiable object
3299 with static storage duration... */
3300 if (TREE_CODE (decl) == VAR_DECL
3301 && current_scope != file_scope
3302 && TREE_STATIC (decl)
3303 && !TREE_READONLY (decl)
3304 && DECL_DECLARED_INLINE_P (current_function_decl)
3305 && DECL_EXTERNAL (current_function_decl))
3306 pedwarn (0, "%q+D is static but declared in inline function %qD "
3307 "which is not static", decl, current_function_decl);
3309 /* Add this decl to the current scope.
3310 TEM may equal DECL or it may be a previous decl of the same name. */
3311 tem = pushdecl (decl);
3313 if (initialized && DECL_EXTERNAL (tem))
3315 DECL_EXTERNAL (tem) = 0;
3316 TREE_STATIC (tem) = 1;
3322 /* Initialize EH if not initialized yet and exceptions are enabled. */
3325 c_maybe_initialize_eh (void)
3327 if (!flag_exceptions || c_eh_initialized_p)
3330 c_eh_initialized_p = true;
3331 eh_personality_libfunc
3332 = init_one_libfunc (USING_SJLJ_EXCEPTIONS
3333 ? "__gcc_personality_sj0"
3334 : "__gcc_personality_v0");
3335 default_init_unwind_resume_libfunc ();
3336 using_eh_for_cleanups ();
3339 /* Finish processing of a declaration;
3340 install its initial value.
3341 If the length of an array type is not known before,
3342 it must be determined now, from the initial value, or it is an error. */
3345 finish_decl (tree decl, tree init, tree asmspec_tree)
3348 int was_incomplete = (DECL_SIZE (decl) == 0);
3349 const char *asmspec = 0;
3351 /* If a name was specified, get the string. */
3352 if ((TREE_CODE (decl) == FUNCTION_DECL || TREE_CODE (decl) == VAR_DECL)
3353 && DECL_FILE_SCOPE_P (decl))
3354 asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
3356 asmspec = TREE_STRING_POINTER (asmspec_tree);
3358 /* If `start_decl' didn't like having an initialization, ignore it now. */
3359 if (init != 0 && DECL_INITIAL (decl) == 0)
3362 /* Don't crash if parm is initialized. */
3363 if (TREE_CODE (decl) == PARM_DECL)
3367 store_init_value (decl, init);
3369 if (c_dialect_objc () && (TREE_CODE (decl) == VAR_DECL
3370 || TREE_CODE (decl) == FUNCTION_DECL
3371 || TREE_CODE (decl) == FIELD_DECL))
3372 objc_check_decl (decl);
3374 type = TREE_TYPE (decl);
3376 /* Deduce size of array from initialization, if not already known. */
3377 if (TREE_CODE (type) == ARRAY_TYPE
3378 && TYPE_DOMAIN (type) == 0
3379 && TREE_CODE (decl) != TYPE_DECL)
3382 = (TREE_STATIC (decl)
3383 /* Even if pedantic, an external linkage array
3384 may have incomplete type at first. */
3385 ? pedantic && !TREE_PUBLIC (decl)
3386 : !DECL_EXTERNAL (decl));
3388 = complete_array_type (&TREE_TYPE (decl), DECL_INITIAL (decl),
3391 /* Get the completed type made by complete_array_type. */
3392 type = TREE_TYPE (decl);
3397 error ("initializer fails to determine size of %q+D", decl);
3402 error ("array size missing in %q+D", decl);
3403 /* If a `static' var's size isn't known,
3404 make it extern as well as static, so it does not get
3406 If it is not `static', then do not mark extern;
3407 finish_incomplete_decl will give it a default size
3408 and it will get allocated. */
3409 else if (!pedantic && TREE_STATIC (decl) && !TREE_PUBLIC (decl))
3410 DECL_EXTERNAL (decl) = 1;
3414 error ("zero or negative size array %q+D", decl);
3418 /* For global variables, update the copy of the type that
3419 exists in the binding. */
3420 if (TREE_PUBLIC (decl))
3422 struct c_binding *b_ext = I_SYMBOL_BINDING (DECL_NAME (decl));
3423 while (b_ext && !B_IN_EXTERNAL_SCOPE (b_ext))
3424 b_ext = b_ext->shadowed;
3428 b_ext->type = composite_type (b_ext->type, type);
3439 if (DECL_INITIAL (decl))
3440 TREE_TYPE (DECL_INITIAL (decl)) = type;
3442 layout_decl (decl, 0);
3445 if (TREE_CODE (decl) == VAR_DECL)
3447 if (init && TREE_CODE (init) == CONSTRUCTOR)
3448 add_flexible_array_elts_to_size (decl, init);
3450 if (DECL_SIZE (decl) == 0 && TREE_TYPE (decl) != error_mark_node
3451 && COMPLETE_TYPE_P (TREE_TYPE (decl)))
3452 layout_decl (decl, 0);
3454 if (DECL_SIZE (decl) == 0
3455 /* Don't give an error if we already gave one earlier. */
3456 && TREE_TYPE (decl) != error_mark_node
3457 && (TREE_STATIC (decl)
3458 /* A static variable with an incomplete type
3459 is an error if it is initialized.
3460 Also if it is not file scope.
3461 Otherwise, let it through, but if it is not `extern'
3462 then it may cause an error message later. */
3463 ? (DECL_INITIAL (decl) != 0
3464 || !DECL_FILE_SCOPE_P (decl))
3465 /* An automatic variable with an incomplete type
3467 : !DECL_EXTERNAL (decl)))
3469 error ("storage size of %q+D isn%'t known", decl);
3470 TREE_TYPE (decl) = error_mark_node;
3473 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
3474 && DECL_SIZE (decl) != 0)
3476 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
3477 constant_expression_warning (DECL_SIZE (decl));
3480 error ("storage size of %q+D isn%'t constant", decl);
3481 TREE_TYPE (decl) = error_mark_node;
3485 if (TREE_USED (type))
3486 TREE_USED (decl) = 1;
3489 /* If this is a function and an assembler name is specified, reset DECL_RTL
3490 so we can give it its new name. Also, update built_in_decls if it
3491 was a normal built-in. */
3492 if (TREE_CODE (decl) == FUNCTION_DECL && asmspec)
3494 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
3495 set_builtin_user_assembler_name (decl, asmspec);
3496 set_user_assembler_name (decl, asmspec);
3499 /* If #pragma weak was used, mark the decl weak now. */
3500 maybe_apply_pragma_weak (decl);
3502 /* Output the assembler code and/or RTL code for variables and functions,
3503 unless the type is an undefined structure or union.
3504 If not, it will get done when the type is completed. */
3506 if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL)
3508 /* Determine the ELF visibility. */
3509 if (TREE_PUBLIC (decl))
3510 c_determine_visibility (decl);
3512 /* This is a no-op in c-lang.c or something real in objc-act.c. */
3513 if (c_dialect_objc ())
3514 objc_check_decl (decl);
3518 /* If this is not a static variable, issue a warning.
3519 It doesn't make any sense to give an ASMSPEC for an
3520 ordinary, non-register local variable. Historically,
3521 GCC has accepted -- but ignored -- the ASMSPEC in
3523 if (!DECL_FILE_SCOPE_P (decl)
3524 && TREE_CODE (decl) == VAR_DECL
3525 && !C_DECL_REGISTER (decl)
3526 && !TREE_STATIC (decl))
3527 warning (0, "ignoring asm-specifier for non-static local "
3528 "variable %q+D", decl);
3530 set_user_assembler_name (decl, asmspec);
3533 if (DECL_FILE_SCOPE_P (decl))
3535 if (DECL_INITIAL (decl) == NULL_TREE
3536 || DECL_INITIAL (decl) == error_mark_node)
3537 /* Don't output anything
3538 when a tentative file-scope definition is seen.
3539 But at end of compilation, do output code for them. */
3540 DECL_DEFER_OUTPUT (decl) = 1;
3541 rest_of_decl_compilation (decl, true, 0);
3545 /* In conjunction with an ASMSPEC, the `register'
3546 keyword indicates that we should place the variable
3547 in a particular register. */
3548 if (asmspec && C_DECL_REGISTER (decl))
3550 DECL_HARD_REGISTER (decl) = 1;
3551 /* This cannot be done for a structure with volatile
3552 fields, on which DECL_REGISTER will have been
3554 if (!DECL_REGISTER (decl))
3555 error ("cannot put object with volatile field into register");
3558 if (TREE_CODE (decl) != FUNCTION_DECL)
3560 /* If we're building a variable sized type, and we might be
3561 reachable other than via the top of the current binding
3562 level, then create a new BIND_EXPR so that we deallocate
3563 the object at the right time. */
3564 /* Note that DECL_SIZE can be null due to errors. */
3565 if (DECL_SIZE (decl)
3566 && !TREE_CONSTANT (DECL_SIZE (decl))
3567 && STATEMENT_LIST_HAS_LABEL (cur_stmt_list))
3570 bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL);
3571 TREE_SIDE_EFFECTS (bind) = 1;
3573 BIND_EXPR_BODY (bind) = push_stmt_list ();
3575 add_stmt (build_stmt (DECL_EXPR, decl));
3580 if (!DECL_FILE_SCOPE_P (decl))
3582 /* Recompute the RTL of a local array now
3583 if it used to be an incomplete type. */
3585 && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl))
3587 /* If we used it already as memory, it must stay in memory. */
3588 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
3589 /* If it's still incomplete now, no init will save it. */
3590 if (DECL_SIZE (decl) == 0)
3591 DECL_INITIAL (decl) = 0;
3596 if (TREE_CODE (decl) == TYPE_DECL)
3598 if (!DECL_FILE_SCOPE_P (decl)
3599 && variably_modified_type_p (TREE_TYPE (decl), NULL_TREE))
3600 add_stmt (build_stmt (DECL_EXPR, decl));
3602 rest_of_decl_compilation (decl, DECL_FILE_SCOPE_P (decl), 0);
3605 /* At the end of a declaration, throw away any variable type sizes
3606 of types defined inside that declaration. There is no use
3607 computing them in the following function definition. */
3608 if (current_scope == file_scope)
3609 get_pending_sizes ();
3611 /* Install a cleanup (aka destructor) if one was given. */
3612 if (TREE_CODE (decl) == VAR_DECL && !TREE_STATIC (decl))
3614 tree attr = lookup_attribute ("cleanup", DECL_ATTRIBUTES (decl));
3617 tree cleanup_id = TREE_VALUE (TREE_VALUE (attr));
3618 tree cleanup_decl = lookup_name (cleanup_id);
3621 /* Build "cleanup(&decl)" for the destructor. */
3622 cleanup = build_unary_op (ADDR_EXPR, decl, 0);
3623 cleanup = build_tree_list (NULL_TREE, cleanup);
3624 cleanup = build_function_call (cleanup_decl, cleanup);
3626 /* Don't warn about decl unused; the cleanup uses it. */
3627 TREE_USED (decl) = 1;
3628 TREE_USED (cleanup_decl) = 1;
3630 /* Initialize EH, if we've been told to do so. */
3631 c_maybe_initialize_eh ();
3633 push_cleanup (decl, cleanup, false);
3638 /* Given a parsed parameter declaration, decode it into a PARM_DECL. */
3641 grokparm (const struct c_parm *parm)
3643 tree attrs = parm->attrs;
3644 tree decl = grokdeclarator (parm->declarator, parm->specs, PARM, false,
3645 NULL, &attrs, DEPRECATED_NORMAL);
3647 decl_attributes (&decl, attrs, 0);
3652 /* Given a parsed parameter declaration, decode it into a PARM_DECL
3653 and push that on the current scope. */
3656 push_parm_decl (const struct c_parm *parm)
3658 tree attrs = parm->attrs;
3661 decl = grokdeclarator (parm->declarator, parm->specs, PARM, false, NULL,
3662 &attrs, DEPRECATED_NORMAL);
3663 decl_attributes (&decl, attrs, 0);
3665 decl = pushdecl (decl);
3667 finish_decl (decl, NULL_TREE, NULL_TREE);
3670 /* Mark all the parameter declarations to date as forward decls.
3671 Also diagnose use of this extension. */
3674 mark_forward_parm_decls (void)
3676 struct c_binding *b;
3678 if (pedantic && !current_scope->warned_forward_parm_decls)
3680 pedwarn (OPT_pedantic, "ISO C forbids forward parameter declarations");
3681 current_scope->warned_forward_parm_decls = true;
3684 for (b = current_scope->bindings; b; b = b->prev)
3685 if (TREE_CODE (b->decl) == PARM_DECL)
3686 TREE_ASM_WRITTEN (b->decl) = 1;
3689 /* Build a COMPOUND_LITERAL_EXPR. TYPE is the type given in the compound
3690 literal, which may be an incomplete array type completed by the
3691 initializer; INIT is a CONSTRUCTOR that initializes the compound
3695 build_compound_literal (tree type, tree init)
3697 /* We do not use start_decl here because we have a type, not a declarator;
3698 and do not use finish_decl because the decl should be stored inside
3699 the COMPOUND_LITERAL_EXPR rather than added elsewhere as a DECL_EXPR. */
3704 if (type == error_mark_node)
3705 return error_mark_node;
3707 decl = build_decl (VAR_DECL, NULL_TREE, type);
3708 DECL_EXTERNAL (decl) = 0;
3709 TREE_PUBLIC (decl) = 0;
3710 TREE_STATIC (decl) = (current_scope == file_scope);
3711 DECL_CONTEXT (decl) = current_function_decl;
3712 TREE_USED (decl) = 1;
3713 TREE_TYPE (decl) = type;
3714 TREE_READONLY (decl) = TYPE_READONLY (type);
3715 store_init_value (decl, init);
3717 if (TREE_CODE (type) == ARRAY_TYPE && !COMPLETE_TYPE_P (type))
3719 int failure = complete_array_type (&TREE_TYPE (decl),
3720 DECL_INITIAL (decl), true);
3721 gcc_assert (!failure);
3723 type = TREE_TYPE (decl);
3724 TREE_TYPE (DECL_INITIAL (decl)) = type;
3727 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
3728 return error_mark_node;
3730 stmt = build_stmt (DECL_EXPR, decl);
3731 complit = build1 (COMPOUND_LITERAL_EXPR, type, stmt);
3732 TREE_SIDE_EFFECTS (complit) = 1;
3734 layout_decl (decl, 0);
3736 if (TREE_STATIC (decl))
3738 /* This decl needs a name for the assembler output. */
3739 set_compound_literal_name (decl);
3740 DECL_DEFER_OUTPUT (decl) = 1;
3741 DECL_COMDAT (decl) = 1;
3742 DECL_ARTIFICIAL (decl) = 1;
3743 DECL_IGNORED_P (decl) = 1;
3745 rest_of_decl_compilation (decl, 1, 0);
3751 /* Determine whether TYPE is a structure with a flexible array member,
3752 or a union containing such a structure (possibly recursively). */
3755 flexible_array_type_p (tree type)
3758 switch (TREE_CODE (type))
3761 x = TYPE_FIELDS (type);
3764 while (TREE_CHAIN (x) != NULL_TREE)
3766 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
3767 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
3768 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
3769 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
3773 for (x = TYPE_FIELDS (type); x != NULL_TREE; x = TREE_CHAIN (x))
3775 if (flexible_array_type_p (TREE_TYPE (x)))
3784 /* Performs sanity checks on the TYPE and WIDTH of the bit-field NAME,
3785 replacing with appropriate values if they are invalid. */
3787 check_bitfield_type_and_width (tree *type, tree *width, const char *orig_name)
3790 unsigned int max_width;
3791 unsigned HOST_WIDE_INT w;
3792 const char *name = orig_name ? orig_name: _("<anonymous>");
3794 /* Detect and ignore out of range field width and process valid
3796 if (!INTEGRAL_TYPE_P (TREE_TYPE (*width))
3797 || TREE_CODE (*width) != INTEGER_CST)
3799 error ("bit-field %qs width not an integer constant", name);
3800 *width = integer_one_node;
3804 constant_expression_warning (*width);
3805 if (tree_int_cst_sgn (*width) < 0)
3807 error ("negative width in bit-field %qs", name);
3808 *width = integer_one_node;
3810 else if (integer_zerop (*width) && orig_name)
3812 error ("zero width for bit-field %qs", name);
3813 *width = integer_one_node;
3817 /* Detect invalid bit-field type. */
3818 if (TREE_CODE (*type) != INTEGER_TYPE
3819 && TREE_CODE (*type) != BOOLEAN_TYPE
3820 && TREE_CODE (*type) != ENUMERAL_TYPE)
3822 error ("bit-field %qs has invalid type", name);
3823 *type = unsigned_type_node;
3826 type_mv = TYPE_MAIN_VARIANT (*type);
3827 if (!in_system_header
3828 && type_mv != integer_type_node
3829 && type_mv != unsigned_type_node
3830 && type_mv != boolean_type_node)
3831 pedwarn (OPT_pedantic, "type of bit-field %qs is a GCC extension", name);
3833 max_width = TYPE_PRECISION (*type);
3835 if (0 < compare_tree_int (*width, max_width))
3837 error ("width of %qs exceeds its type", name);
3839 *width = build_int_cst (NULL_TREE, w);
3842 w = tree_low_cst (*width, 1);
3844 if (TREE_CODE (*type) == ENUMERAL_TYPE)
3846 struct lang_type *lt = TYPE_LANG_SPECIFIC (*type);
3848 || w < min_precision (lt->enum_min, TYPE_UNSIGNED (*type))
3849 || w < min_precision (lt->enum_max, TYPE_UNSIGNED (*type)))
3850 warning (0, "%qs is narrower than values of its type", name);
3856 /* Print warning about variable length array if necessary. */
3859 warn_variable_length_array (const char *name, tree size)
3861 int const_size = TREE_CONSTANT (size);
3863 if (!flag_isoc99 && pedantic && warn_vla != 0)
3868 pedwarn (OPT_Wvla, "ISO C90 forbids array %qs whose size "
3869 "can%'t be evaluated",
3872 pedwarn (OPT_Wvla, "ISO C90 forbids array whose size "
3873 "can%'t be evaluated");
3878 pedwarn (OPT_Wvla, "ISO C90 forbids variable length array %qs",
3881 pedwarn (OPT_Wvla, "ISO C90 forbids variable length array");
3884 else if (warn_vla > 0)
3890 "the size of array %qs can"
3891 "%'t be evaluated", name);
3894 "the size of array can %'t be evaluated");
3900 "variable length array %qs is used",
3904 "variable length array is used");
3909 /* Given declspecs and a declarator,
3910 determine the name and type of the object declared
3911 and construct a ..._DECL node for it.
3912 (In one case we can return a ..._TYPE node instead.
3913 For invalid input we sometimes return 0.)
3915 DECLSPECS is a c_declspecs structure for the declaration specifiers.
3917 DECL_CONTEXT says which syntactic context this declaration is in:
3918 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
3919 FUNCDEF for a function definition. Like NORMAL but a few different
3920 error messages in each case. Return value may be zero meaning
3921 this definition is too screwy to try to parse.
3922 PARM for a parameter declaration (either within a function prototype
3923 or before a function body). Make a PARM_DECL, or return void_type_node.
3924 TYPENAME if for a typename (in a cast or sizeof).
3925 Don't make a DECL node; just return the ..._TYPE node.
3926 FIELD for a struct or union field; make a FIELD_DECL.
3927 INITIALIZED is true if the decl has an initializer.
3928 WIDTH is non-NULL for bit-fields, and is a pointer to an INTEGER_CST node
3929 representing the width of the bit-field.
3930 DECL_ATTRS points to the list of attributes that should be added to this
3931 decl. Any nested attributes that belong on the decl itself will be
3933 DEPRECATED_STATE is a deprecated_states value indicating whether
3934 deprecation warnings should be suppressed.
3936 In the TYPENAME case, DECLARATOR is really an absolute declarator.
3937 It may also be so in the PARM case, for a prototype where the
3938 argument type is specified but not the name.
3940 This function is where the complicated C meanings of `static'
3941 and `extern' are interpreted. */
3944 grokdeclarator (const struct c_declarator *declarator,
3945 struct c_declspecs *declspecs,
3946 enum decl_context decl_context, bool initialized, tree *width,
3947 tree *decl_attrs, enum deprecated_states deprecated_state)
3949 tree type = declspecs->type;
3950 bool threadp = declspecs->thread_p;
3951 enum c_storage_class storage_class = declspecs->storage_class;
3955 int type_quals = TYPE_UNQUALIFIED;
3956 const char *name, *orig_name;
3957 bool funcdef_flag = false;
3958 bool funcdef_syntax = false;
3959 int size_varies = 0;
3960 tree decl_attr = declspecs->decl_attr;
3961 int array_ptr_quals = TYPE_UNQUALIFIED;
3962 tree array_ptr_attrs = NULL_TREE;
3963 int array_parm_static = 0;
3964 bool array_parm_vla_unspec_p = false;
3965 tree returned_attrs = NULL_TREE;
3966 bool bitfield = width != NULL;
3968 struct c_arg_info *arg_info = 0;
3970 if (decl_context == FUNCDEF)
3971 funcdef_flag = true, decl_context = NORMAL;
3973 /* Look inside a declarator for the name being declared
3974 and get it as a string, for an error message. */
3976 const struct c_declarator *decl = declarator;
3985 funcdef_syntax = (decl->kind == cdk_function);
3986 decl = decl->declarator;
3990 decl = decl->declarator;
3995 name = IDENTIFIER_POINTER (decl->u.id);
4007 /* A function definition's declarator must have the form of
4008 a function declarator. */
4010 if (funcdef_flag && !funcdef_syntax)
4013 /* If this looks like a function definition, make it one,
4014 even if it occurs where parms are expected.
4015 Then store_parm_decls will reject it and not use it as a parm. */
4016 if (decl_context == NORMAL && !funcdef_flag && current_scope->parm_flag)
4017 decl_context = PARM;
4019 if (declspecs->deprecated_p && deprecated_state != DEPRECATED_SUPPRESS)
4020 warn_deprecated_use (declspecs->type);
4022 if ((decl_context == NORMAL || decl_context == FIELD)
4023 && current_scope == file_scope
4024 && variably_modified_type_p (type, NULL_TREE))
4026 error ("variably modified %qs at file scope", name);
4027 type = integer_type_node;
4030 size_varies = C_TYPE_VARIABLE_SIZE (type);
4032 /* Diagnose defaulting to "int". */
4034 if (declspecs->default_int_p && !in_system_header)
4036 /* Issue a warning if this is an ISO C 99 program or if
4037 -Wreturn-type and this is a function, or if -Wimplicit;
4038 prefer the former warning since it is more explicit. */
4039 if ((warn_implicit_int || warn_return_type || flag_isoc99)
4041 warn_about_return_type = 1;
4043 pedwarn_c99 (flag_isoc99 ? 0 : OPT_Wimplicit_int,
4044 "type defaults to %<int%> in declaration of %qs", name);
4047 /* Adjust the type if a bit-field is being declared,
4048 -funsigned-bitfields applied and the type is not explicitly
4050 if (bitfield && !flag_signed_bitfields && !declspecs->explicit_signed_p
4051 && TREE_CODE (type) == INTEGER_TYPE)
4052 type = unsigned_type_for (type);
4054 /* Figure out the type qualifiers for the declaration. There are
4055 two ways a declaration can become qualified. One is something
4056 like `const int i' where the `const' is explicit. Another is
4057 something like `typedef const int CI; CI i' where the type of the
4058 declaration contains the `const'. A third possibility is that
4059 there is a type qualifier on the element type of a typedefed
4060 array type, in which case we should extract that qualifier so
4061 that c_apply_type_quals_to_decl receives the full list of
4062 qualifiers to work with (C90 is not entirely clear about whether
4063 duplicate qualifiers should be diagnosed in this case, but it
4064 seems most appropriate to do so). */
4065 element_type = strip_array_types (type);
4066 constp = declspecs->const_p + TYPE_READONLY (element_type);
4067 restrictp = declspecs->restrict_p + TYPE_RESTRICT (element_type);
4068 volatilep = declspecs->volatile_p + TYPE_VOLATILE (element_type);
4069 if (pedantic && !flag_isoc99)
4072 pedwarn (OPT_pedantic, "duplicate %<const%>");
4074 pedwarn (OPT_pedantic, "duplicate %<restrict%>");
4076 pedwarn (OPT_pedantic, "duplicate %<volatile%>");
4078 if (!flag_gen_aux_info && (TYPE_QUALS (element_type)))
4079 type = TYPE_MAIN_VARIANT (type);
4080 type_quals = ((constp ? TYPE_QUAL_CONST : 0)
4081 | (restrictp ? TYPE_QUAL_RESTRICT : 0)
4082 | (volatilep ? TYPE_QUAL_VOLATILE : 0));
4084 /* Warn about storage classes that are invalid for certain
4085 kinds of declarations (parameters, typenames, etc.). */
4089 || storage_class == csc_auto
4090 || storage_class == csc_register
4091 || storage_class == csc_typedef))
4093 if (storage_class == csc_auto)
4094 pedwarn ((current_scope == file_scope) ? 0 : OPT_pedantic,
4095 "function definition declared %<auto%>");
4096 if (storage_class == csc_register)
4097 error ("function definition declared %<register%>");
4098 if (storage_class == csc_typedef)
4099 error ("function definition declared %<typedef%>");
4101 error ("function definition declared %<__thread%>");
4103 if (storage_class == csc_auto
4104 || storage_class == csc_register
4105 || storage_class == csc_typedef)
4106 storage_class = csc_none;
4108 else if (decl_context != NORMAL && (storage_class != csc_none || threadp))
4110 if (decl_context == PARM && storage_class == csc_register)
4114 switch (decl_context)
4117 error ("storage class specified for structure field %qs",
4121 error ("storage class specified for parameter %qs", name);
4124 error ("storage class specified for typename");
4127 storage_class = csc_none;
4131 else if (storage_class == csc_extern
4135 /* 'extern' with initialization is invalid if not at file scope. */
4136 if (current_scope == file_scope)
4138 /* It is fine to have 'extern const' when compiling at C
4139 and C++ intersection. */
4140 if (!(warn_cxx_compat && constp))
4141 warning (0, "%qs initialized and declared %<extern%>", name);
4144 error ("%qs has both %<extern%> and initializer", name);
4146 else if (current_scope == file_scope)
4148 if (storage_class == csc_auto)
4149 error ("file-scope declaration of %qs specifies %<auto%>", name);
4150 if (pedantic && storage_class == csc_register)
4151 pedwarn (OPT_pedantic, "file-scope declaration of %qs specifies %<register%>", name);
4155 if (storage_class == csc_extern && funcdef_flag)
4156 error ("nested function %qs declared %<extern%>", name);
4157 else if (threadp && storage_class == csc_none)
4159 error ("function-scope %qs implicitly auto and declared "
4166 /* Now figure out the structure of the declarator proper.
4167 Descend through it, creating more complex types, until we reach
4168 the declared identifier (or NULL_TREE, in an absolute declarator).
4169 At each stage we maintain an unqualified version of the type
4170 together with any qualifiers that should be applied to it with
4171 c_build_qualified_type; this way, array types including
4172 multidimensional array types are first built up in unqualified
4173 form and then the qualified form is created with
4174 TYPE_MAIN_VARIANT pointing to the unqualified form. */
4176 while (declarator && declarator->kind != cdk_id)
4178 if (type == error_mark_node)
4180 declarator = declarator->declarator;
4184 /* Each level of DECLARATOR is either a cdk_array (for ...[..]),
4185 a cdk_pointer (for *...),
4186 a cdk_function (for ...(...)),
4187 a cdk_attrs (for nested attributes),
4188 or a cdk_id (for the name being declared
4189 or the place in an absolute declarator
4190 where the name was omitted).
4191 For the last case, we have just exited the loop.
4193 At this point, TYPE is the type of elements of an array,
4194 or for a function to return, or for a pointer to point to.
4195 After this sequence of ifs, TYPE is the type of the
4196 array or function or pointer, and DECLARATOR has had its
4197 outermost layer removed. */
4199 if (array_ptr_quals != TYPE_UNQUALIFIED
4200 || array_ptr_attrs != NULL_TREE
4201 || array_parm_static)
4203 /* Only the innermost declarator (making a parameter be of
4204 array type which is converted to pointer type)
4205 may have static or type qualifiers. */
4206 error ("static or type qualifiers in non-parameter array declarator");
4207 array_ptr_quals = TYPE_UNQUALIFIED;
4208 array_ptr_attrs = NULL_TREE;
4209 array_parm_static = 0;
4212 switch (declarator->kind)
4216 /* A declarator with embedded attributes. */
4217 tree attrs = declarator->u.attrs;
4218 const struct c_declarator *inner_decl;
4220 declarator = declarator->declarator;
4221 inner_decl = declarator;
4222 while (inner_decl->kind == cdk_attrs)
4223 inner_decl = inner_decl->declarator;
4224 if (inner_decl->kind == cdk_id)
4225 attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
4226 else if (inner_decl->kind == cdk_function)
4227 attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
4228 else if (inner_decl->kind == cdk_array)
4229 attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
4230 returned_attrs = decl_attributes (&type,
4231 chainon (returned_attrs, attrs),
4237 tree itype = NULL_TREE;
4238 tree size = declarator->u.array.dimen;
4239 /* The index is a signed object `sizetype' bits wide. */
4240 tree index_type = c_common_signed_type (sizetype);
4242 array_ptr_quals = declarator->u.array.quals;
4243 array_ptr_attrs = declarator->u.array.attrs;
4244 array_parm_static = declarator->u.array.static_p;
4245 array_parm_vla_unspec_p = declarator->u.array.vla_unspec_p;
4247 declarator = declarator->declarator;
4249 /* Check for some types that there cannot be arrays of. */
4251 if (VOID_TYPE_P (type))
4253 error ("declaration of %qs as array of voids", name);
4254 type = error_mark_node;
4257 if (TREE_CODE (type) == FUNCTION_TYPE)
4259 error ("declaration of %qs as array of functions", name);
4260 type = error_mark_node;
4263 if (pedantic && !in_system_header && flexible_array_type_p (type))
4264 pedwarn (OPT_pedantic, "invalid use of structure with flexible array member");
4266 if (size == error_mark_node)
4267 type = error_mark_node;
4269 if (type == error_mark_node)
4272 /* If size was specified, set ITYPE to a range-type for
4273 that size. Otherwise, ITYPE remains null. finish_decl
4274 may figure it out from an initial value. */
4278 /* Strip NON_LVALUE_EXPRs since we aren't using as an
4280 STRIP_TYPE_NOPS (size);
4282 if (!INTEGRAL_TYPE_P (TREE_TYPE (size)))
4284 error ("size of array %qs has non-integer type", name);
4285 size = integer_one_node;
4288 if (pedantic && integer_zerop (size))
4289 pedwarn (OPT_pedantic, "ISO C forbids zero-size array %qs", name);
4291 if (TREE_CODE (size) == INTEGER_CST)
4293 constant_expression_warning (size);
4294 if (tree_int_cst_sgn (size) < 0)
4296 error ("size of array %qs is negative", name);
4297 size = integer_one_node;
4300 else if ((decl_context == NORMAL || decl_context == FIELD)
4301 && current_scope == file_scope)
4303 error ("variably modified %qs at file scope", name);
4304 size = integer_one_node;
4308 /* Make sure the array size remains visibly
4309 nonconstant even if it is (eg) a const variable
4310 with known value. */
4312 warn_variable_length_array (orig_name, size);
4315 if (integer_zerop (size))
4317 /* A zero-length array cannot be represented with
4318 an unsigned index type, which is what we'll
4319 get with build_index_type. Create an
4320 open-ended range instead. */
4321 itype = build_range_type (sizetype, size, NULL_TREE);
4325 /* Arrange for the SAVE_EXPR on the inside of the
4326 MINUS_EXPR, which allows the -1 to get folded
4327 with the +1 that happens when building TYPE_SIZE. */
4329 size = variable_size (size);
4331 /* Compute the maximum valid index, that is, size
4332 - 1. Do the calculation in index_type, so that
4333 if it is a variable the computations will be
4334 done in the proper mode. */
4335 itype = fold_build2 (MINUS_EXPR, index_type,
4336 convert (index_type, size),
4337 convert (index_type,
4340 /* If that overflowed, the array is too big. ???
4341 While a size of INT_MAX+1 technically shouldn't
4342 cause an overflow (because we subtract 1), the
4343 overflow is recorded during the conversion to
4344 index_type, before the subtraction. Handling
4345 this case seems like an unnecessary
4347 if (TREE_CODE (itype) == INTEGER_CST
4348 && TREE_OVERFLOW (itype))
4350 error ("size of array %qs is too large", name);
4351 type = error_mark_node;
4355 itype = build_index_type (itype);
4358 else if (decl_context == FIELD)
4360 if (pedantic && !flag_isoc99 && !in_system_header)
4361 pedwarn (OPT_pedantic, "ISO C90 does not support flexible array members");
4363 /* ISO C99 Flexible array members are effectively
4364 identical to GCC's zero-length array extension. */
4365 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4367 else if (decl_context == PARM)
4369 if (array_parm_vla_unspec_p)
4374 error ("%<[*]%> not allowed in other than a declaration");
4377 itype = build_range_type (sizetype, size_zero_node, NULL_TREE);
4381 else if (decl_context == TYPENAME)
4383 if (array_parm_vla_unspec_p)
4385 /* The error is printed elsewhere. We use this to
4386 avoid messing up with incomplete array types of
4387 the same type, that would otherwise be modified
4389 itype = build_range_type (sizetype, size_zero_node,
4394 /* Complain about arrays of incomplete types. */
4395 if (!COMPLETE_TYPE_P (type))
4397 error ("array type has incomplete element type");
4398 type = error_mark_node;
4401 /* When itype is NULL, a shared incomplete array type is
4402 returned for all array of a given type. Elsewhere we
4403 make sure we don't complete that type before copying
4404 it, but here we want to make sure we don't ever
4405 modify the shared type, so we gcc_assert (itype)
4407 type = build_array_type (type, itype);
4409 if (type != error_mark_node)
4413 /* It is ok to modify type here even if itype is
4414 NULL: if size_varies, we're in a
4415 multi-dimensional array and the inner type has
4416 variable size, so the enclosing shared array type
4418 if (size && TREE_CODE (size) == INTEGER_CST)
4420 = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4421 C_TYPE_VARIABLE_SIZE (type) = 1;
4424 /* The GCC extension for zero-length arrays differs from
4425 ISO flexible array members in that sizeof yields
4427 if (size && integer_zerop (size))
4430 TYPE_SIZE (type) = bitsize_zero_node;
4431 TYPE_SIZE_UNIT (type) = size_zero_node;
4433 if (array_parm_vla_unspec_p)
4436 /* The type is complete. C99 6.7.5.2p4 */
4437 TYPE_SIZE (type) = bitsize_zero_node;
4438 TYPE_SIZE_UNIT (type) = size_zero_node;
4442 if (decl_context != PARM
4443 && (array_ptr_quals != TYPE_UNQUALIFIED
4444 || array_ptr_attrs != NULL_TREE
4445 || array_parm_static))
4447 error ("static or type qualifiers in non-parameter array declarator");
4448 array_ptr_quals = TYPE_UNQUALIFIED;
4449 array_ptr_attrs = NULL_TREE;
4450 array_parm_static = 0;
4456 /* Say it's a definition only for the declarator closest
4457 to the identifier, apart possibly from some
4459 bool really_funcdef = false;
4463 const struct c_declarator *t = declarator->declarator;
4464 while (t->kind == cdk_attrs)
4466 really_funcdef = (t->kind == cdk_id);
4469 /* Declaring a function type. Make sure we have a valid
4470 type for the function to return. */
4471 if (type == error_mark_node)
4476 /* Warn about some types functions can't return. */
4477 if (TREE_CODE (type) == FUNCTION_TYPE)
4479 error ("%qs declared as function returning a function", name);
4480 type = integer_type_node;
4482 if (TREE_CODE (type) == ARRAY_TYPE)
4484 error ("%qs declared as function returning an array", name);
4485 type = integer_type_node;
4488 /* Construct the function type and go to the next
4489 inner layer of declarator. */
4490 arg_info = declarator->u.arg_info;
4491 arg_types = grokparms (arg_info, really_funcdef);
4493 put_pending_sizes (arg_info->pending_sizes);
4495 /* Type qualifiers before the return type of the function
4496 qualify the return type, not the function type. */
4499 /* Type qualifiers on a function return type are
4500 normally permitted by the standard but have no
4501 effect, so give a warning at -Wreturn-type.
4502 Qualifiers on a void return type are banned on
4503 function definitions in ISO C; GCC used to used
4504 them for noreturn functions. */
4505 if (VOID_TYPE_P (type) && really_funcdef)
4506 pedwarn (0, "function definition has qualified void return type");
4508 warning (OPT_Wignored_qualifiers,
4509 "type qualifiers ignored on function return type");
4511 type = c_build_qualified_type (type, type_quals);
4513 type_quals = TYPE_UNQUALIFIED;
4515 type = build_function_type (type, arg_types);
4516 declarator = declarator->declarator;
4518 /* Set the TYPE_CONTEXTs for each tagged type which is local to
4519 the formal parameter list of this FUNCTION_TYPE to point to
4520 the FUNCTION_TYPE node itself. */
4524 for (link = arg_info->tags;
4526 link = TREE_CHAIN (link))
4527 TYPE_CONTEXT (TREE_VALUE (link)) = type;
4533 /* Merge any constancy or volatility into the target type
4536 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4538 pedwarn (OPT_pedantic, "ISO C forbids qualified function types");
4540 type = c_build_qualified_type (type, type_quals);
4543 /* When the pointed-to type involves components of variable size,
4544 care must be taken to ensure that the size evaluation code is
4545 emitted early enough to dominate all the possible later uses
4546 and late enough for the variables on which it depends to have
4549 This is expected to happen automatically when the pointed-to
4550 type has a name/declaration of it's own, but special attention
4551 is required if the type is anonymous.
4553 We handle the NORMAL and FIELD contexts here by attaching an
4554 artificial TYPE_DECL to such pointed-to type. This forces the
4555 sizes evaluation at a safe point and ensures it is not deferred
4556 until e.g. within a deeper conditional context.
4558 We expect nothing to be needed here for PARM or TYPENAME.
4559 Pushing a TYPE_DECL at this point for TYPENAME would actually
4560 be incorrect, as we might be in the middle of an expression
4561 with side effects on the pointed-to type size "arguments" prior
4562 to the pointer declaration point and the fake TYPE_DECL in the
4563 enclosing context would force the size evaluation prior to the
4566 if (!TYPE_NAME (type)
4567 && (decl_context == NORMAL || decl_context == FIELD)
4568 && variably_modified_type_p (type, NULL_TREE))
4570 tree decl = build_decl (TYPE_DECL, NULL_TREE, type);
4571 DECL_ARTIFICIAL (decl) = 1;
4573 finish_decl (decl, NULL_TREE, NULL_TREE);
4574 TYPE_NAME (type) = decl;
4577 type = build_pointer_type (type);
4579 /* Process type qualifiers (such as const or volatile)
4580 that were given inside the `*'. */
4581 type_quals = declarator->u.pointer_quals;
4583 declarator = declarator->declarator;
4590 *decl_attrs = chainon (returned_attrs, *decl_attrs);
4592 /* Now TYPE has the actual type, apart from any qualifiers in
4595 /* Check the type and width of a bit-field. */
4597 check_bitfield_type_and_width (&type, width, orig_name);
4599 /* Did array size calculations overflow? */
4601 if (TREE_CODE (type) == ARRAY_TYPE
4602 && COMPLETE_TYPE_P (type)
4603 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST
4604 && TREE_OVERFLOW (TYPE_SIZE_UNIT (type)))
4606 error ("size of array %qs is too large", name);
4607 /* If we proceed with the array type as it is, we'll eventually
4608 crash in tree_low_cst(). */
4609 type = error_mark_node;
4612 /* If this is declaring a typedef name, return a TYPE_DECL. */
4614 if (storage_class == csc_typedef)
4617 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4619 pedwarn (OPT_pedantic, "ISO C forbids qualified function types");
4621 type = c_build_qualified_type (type, type_quals);
4622 decl = build_decl (TYPE_DECL, declarator->u.id, type);
4623 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
4624 if (declspecs->explicit_signed_p)
4625 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
4626 if (declspecs->inline_p)
4627 pedwarn (0, "typedef %q+D declared %<inline%>", decl);
4631 /* If this is a type name (such as, in a cast or sizeof),
4632 compute the type and return it now. */
4634 if (decl_context == TYPENAME)
4636 /* Note that the grammar rejects storage classes in typenames
4638 gcc_assert (storage_class == csc_none && !threadp
4639 && !declspecs->inline_p);
4640 if (pedantic && TREE_CODE (type) == FUNCTION_TYPE
4642 pedwarn (OPT_pedantic, "ISO C forbids const or volatile function types");
4644 type = c_build_qualified_type (type, type_quals);
4648 if (pedantic && decl_context == FIELD
4649 && variably_modified_type_p (type, NULL_TREE))
4652 pedwarn (OPT_pedantic,
4653 "a member of a structure or union cannot have a variably modified type");
4656 /* Aside from typedefs and type names (handle above),
4657 `void' at top level (not within pointer)
4658 is allowed only in public variables.
4659 We don't complain about parms either, but that is because
4660 a better error message can be made later. */
4662 if (VOID_TYPE_P (type) && decl_context != PARM
4663 && !((decl_context != FIELD && TREE_CODE (type) != FUNCTION_TYPE)
4664 && (storage_class == csc_extern
4665 || (current_scope == file_scope
4666 && !(storage_class == csc_static
4667 || storage_class == csc_register)))))
4669 error ("variable or field %qs declared void", name);
4670 type = integer_type_node;
4673 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
4674 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
4679 if (decl_context == PARM)
4683 /* A parameter declared as an array of T is really a pointer to T.
4684 One declared as a function is really a pointer to a function. */
4686 if (TREE_CODE (type) == ARRAY_TYPE)
4688 /* Transfer const-ness of array into that of type pointed to. */
4689 type = TREE_TYPE (type);
4691 type = c_build_qualified_type (type, type_quals);
4692 type = build_pointer_type (type);
4693 type_quals = array_ptr_quals;
4695 type = c_build_qualified_type (type, type_quals);
4697 /* We don't yet implement attributes in this context. */
4698 if (array_ptr_attrs != NULL_TREE)
4699 warning (OPT_Wattributes,
4700 "attributes in parameter array declarator ignored");
4704 else if (TREE_CODE (type) == FUNCTION_TYPE)
4707 pedwarn (OPT_pedantic, "ISO C forbids qualified function types");
4709 type = c_build_qualified_type (type, type_quals);
4710 type = build_pointer_type (type);
4711 type_quals = TYPE_UNQUALIFIED;
4713 else if (type_quals)
4714 type = c_build_qualified_type (type, type_quals);
4716 decl = build_decl (PARM_DECL, declarator->u.id, type);
4717 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
4719 C_DECL_VARIABLE_SIZE (decl) = 1;
4721 /* Compute the type actually passed in the parmlist,
4722 for the case where there is no prototype.
4723 (For example, shorts and chars are passed as ints.)
4724 When there is a prototype, this is overridden later. */
4726 if (type == error_mark_node)
4727 promoted_type = type;
4729 promoted_type = c_type_promotes_to (type);
4731 DECL_ARG_TYPE (decl) = promoted_type;
4732 if (declspecs->inline_p)
4733 pedwarn (0, "parameter %q+D declared %<inline%>", decl);
4735 else if (decl_context == FIELD)
4737 /* Note that the grammar rejects storage classes in typenames
4739 gcc_assert (storage_class == csc_none && !threadp
4740 && !declspecs->inline_p);
4742 /* Structure field. It may not be a function. */
4744 if (TREE_CODE (type) == FUNCTION_TYPE)
4746 error ("field %qs declared as a function", name);
4747 type = build_pointer_type (type);
4749 else if (TREE_CODE (type) != ERROR_MARK
4750 && !COMPLETE_OR_UNBOUND_ARRAY_TYPE_P (type))
4752 error ("field %qs has incomplete type", name);
4753 type = error_mark_node;
4755 type = c_build_qualified_type (type, type_quals);
4756 decl = build_decl (FIELD_DECL, declarator->u.id, type);
4757 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
4758 DECL_NONADDRESSABLE_P (decl) = bitfield;
4759 if (bitfield && !declarator->u.id)
4760 TREE_NO_WARNING (decl) = 1;
4763 C_DECL_VARIABLE_SIZE (decl) = 1;
4765 else if (TREE_CODE (type) == FUNCTION_TYPE)
4767 if (storage_class == csc_register || threadp)
4769 error ("invalid storage class for function %qs", name);
4771 else if (current_scope != file_scope)
4773 /* Function declaration not at file scope. Storage
4774 classes other than `extern' are not allowed, C99
4775 6.7.1p5, and `extern' makes no difference. However,
4776 GCC allows 'auto', perhaps with 'inline', to support
4777 nested functions. */
4778 if (storage_class == csc_auto)
4779 pedwarn (OPT_pedantic, "invalid storage class for function %qs", name);
4780 else if (storage_class == csc_static)
4782 error ("invalid storage class for function %qs", name);
4784 storage_class = declspecs->storage_class = csc_none;
4790 decl = build_decl (FUNCTION_DECL, declarator->u.id, type);
4791 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
4792 decl = build_decl_attribute_variant (decl, decl_attr);
4794 if (pedantic && type_quals && !DECL_IN_SYSTEM_HEADER (decl))
4795 pedwarn (OPT_pedantic,
4796 "ISO C forbids qualified function types");
4798 /* GNU C interprets a volatile-qualified function type to indicate
4799 that the function does not return. */
4800 if ((type_quals & TYPE_QUAL_VOLATILE)
4801 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl))))
4802 warning (0, "%<noreturn%> function returns non-void value");
4804 /* Every function declaration is an external reference
4805 (DECL_EXTERNAL) except for those which are not at file
4806 scope and are explicitly declared "auto". This is
4807 forbidden by standard C (C99 6.7.1p5) and is interpreted by
4808 GCC to signify a forward declaration of a nested function. */
4809 if (storage_class == csc_auto && current_scope != file_scope)
4810 DECL_EXTERNAL (decl) = 0;
4811 /* In C99, a function which is declared 'inline' with 'extern'
4812 is not an external reference (which is confusing). It
4813 means that the later definition of the function must be output
4814 in this file, C99 6.7.4p6. In GNU C89, a function declared
4815 'extern inline' is an external reference. */
4816 else if (declspecs->inline_p && storage_class != csc_static)
4817 DECL_EXTERNAL (decl) = ((storage_class == csc_extern)
4818 == flag_gnu89_inline);
4820 DECL_EXTERNAL (decl) = !initialized;
4822 /* Record absence of global scope for `static' or `auto'. */
4824 = !(storage_class == csc_static || storage_class == csc_auto);
4826 /* For a function definition, record the argument information
4827 block where store_parm_decls will look for it. */
4829 current_function_arg_info = arg_info;
4831 if (declspecs->default_int_p)
4832 C_FUNCTION_IMPLICIT_INT (decl) = 1;
4834 /* Record presence of `inline', if it is reasonable. */
4835 if (flag_hosted && MAIN_NAME_P (declarator->u.id))
4837 if (declspecs->inline_p)
4838 pedwarn (0, "cannot inline function %<main%>");
4840 else if (declspecs->inline_p)
4841 /* Record that the function is declared `inline'. */
4842 DECL_DECLARED_INLINE_P (decl) = 1;
4846 /* It's a variable. */
4847 /* An uninitialized decl with `extern' is a reference. */
4848 int extern_ref = !initialized && storage_class == csc_extern;
4850 type = c_build_qualified_type (type, type_quals);
4852 /* C99 6.2.2p7: It is invalid (compile-time undefined
4853 behavior) to create an 'extern' declaration for a
4854 variable if there is a global declaration that is
4855 'static' and the global declaration is not visible.
4856 (If the static declaration _is_ currently visible,
4857 the 'extern' declaration is taken to refer to that decl.) */
4858 if (extern_ref && current_scope != file_scope)
4860 tree global_decl = identifier_global_value (declarator->u.id);
4861 tree visible_decl = lookup_name (declarator->u.id);
4864 && global_decl != visible_decl
4865 && TREE_CODE (global_decl) == VAR_DECL
4866 && !TREE_PUBLIC (global_decl))
4867 error ("variable previously declared %<static%> redeclared "
4871 decl = build_decl (VAR_DECL, declarator->u.id, type);
4872 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
4874 C_DECL_VARIABLE_SIZE (decl) = 1;
4876 if (declspecs->inline_p)
4877 pedwarn (0, "variable %q+D declared %<inline%>", decl);
4879 /* At file scope, an initialized extern declaration may follow
4880 a static declaration. In that case, DECL_EXTERNAL will be
4881 reset later in start_decl. */
4882 DECL_EXTERNAL (decl) = (storage_class == csc_extern);
4884 /* At file scope, the presence of a `static' or `register' storage
4885 class specifier, or the absence of all storage class specifiers
4886 makes this declaration a definition (perhaps tentative). Also,
4887 the absence of `static' makes it public. */
4888 if (current_scope == file_scope)
4890 TREE_PUBLIC (decl) = storage_class != csc_static;
4891 TREE_STATIC (decl) = !extern_ref;
4893 /* Not at file scope, only `static' makes a static definition. */
4896 TREE_STATIC (decl) = (storage_class == csc_static);
4897 TREE_PUBLIC (decl) = extern_ref;
4901 DECL_TLS_MODEL (decl) = decl_default_tls_model (decl);
4904 if (storage_class == csc_extern
4905 && variably_modified_type_p (type, NULL_TREE))
4908 error ("object with variably modified type must have no linkage");
4911 /* Record `register' declaration for warnings on &
4912 and in case doing stupid register allocation. */
4914 if (storage_class == csc_register)
4916 C_DECL_REGISTER (decl) = 1;
4917 DECL_REGISTER (decl) = 1;
4920 /* Record constancy and volatility. */
4921 c_apply_type_quals_to_decl (type_quals, decl);
4923 /* If a type has volatile components, it should be stored in memory.
4924 Otherwise, the fact that those components are volatile
4925 will be ignored, and would even crash the compiler.
4926 Of course, this only makes sense on VAR,PARM, and RESULT decl's. */
4927 if (C_TYPE_FIELDS_VOLATILE (TREE_TYPE (decl))
4928 && (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL
4929 || TREE_CODE (decl) == RESULT_DECL))
4931 /* It is not an error for a structure with volatile fields to
4932 be declared register, but reset DECL_REGISTER since it
4933 cannot actually go in a register. */
4934 int was_reg = C_DECL_REGISTER (decl);
4935 C_DECL_REGISTER (decl) = 0;
4936 DECL_REGISTER (decl) = 0;
4937 c_mark_addressable (decl);
4938 C_DECL_REGISTER (decl) = was_reg;
4941 /* This is the earliest point at which we might know the assembler
4942 name of a variable. Thus, if it's known before this, die horribly. */
4943 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl));
4949 /* Decode the parameter-list info for a function type or function definition.
4950 The argument is the value returned by `get_parm_info' (or made in c-parse.c
4951 if there is an identifier list instead of a parameter decl list).
4952 These two functions are separate because when a function returns
4953 or receives functions then each is called multiple times but the order
4954 of calls is different. The last call to `grokparms' is always the one
4955 that contains the formal parameter names of a function definition.
4957 Return a list of arg types to use in the FUNCTION_TYPE for this function.
4959 FUNCDEF_FLAG is true for a function definition, false for
4960 a mere declaration. A nonempty identifier-list gets an error message
4961 when FUNCDEF_FLAG is false. */
4964 grokparms (struct c_arg_info *arg_info, bool funcdef_flag)
4966 tree arg_types = arg_info->types;
4968 if (funcdef_flag && arg_info->had_vla_unspec)
4970 /* A function definition isn't function prototype scope C99 6.2.1p4. */
4972 error ("%<[*]%> not allowed in other than function prototype scope");
4975 if (arg_types == 0 && !funcdef_flag && !in_system_header)
4976 warning (OPT_Wstrict_prototypes,
4977 "function declaration isn%'t a prototype");
4979 if (arg_types == error_mark_node)
4980 return 0; /* don't set TYPE_ARG_TYPES in this case */
4982 else if (arg_types && TREE_CODE (TREE_VALUE (arg_types)) == IDENTIFIER_NODE)
4985 pedwarn (0, "parameter names (without types) in function declaration");
4987 arg_info->parms = arg_info->types;
4988 arg_info->types = 0;
4993 tree parm, type, typelt;
4994 unsigned int parmno;
4996 /* If there is a parameter of incomplete type in a definition,
4997 this is an error. In a declaration this is valid, and a
4998 struct or union type may be completed later, before any calls
4999 or definition of the function. In the case where the tag was
5000 first declared within the parameter list, a warning has
5001 already been given. If a parameter has void type, then
5002 however the function cannot be defined or called, so
5005 for (parm = arg_info->parms, typelt = arg_types, parmno = 1;
5007 parm = TREE_CHAIN (parm), typelt = TREE_CHAIN (typelt), parmno++)
5009 type = TREE_VALUE (typelt);
5010 if (type == error_mark_node)
5013 if (!COMPLETE_TYPE_P (type))
5017 if (DECL_NAME (parm))
5018 error ("parameter %u (%q+D) has incomplete type",
5021 error ("%Jparameter %u has incomplete type",
5024 TREE_VALUE (typelt) = error_mark_node;
5025 TREE_TYPE (parm) = error_mark_node;
5027 else if (VOID_TYPE_P (type))
5029 if (DECL_NAME (parm))
5030 warning (0, "parameter %u (%q+D) has void type",
5033 warning (0, "%Jparameter %u has void type",
5038 if (DECL_NAME (parm) && TREE_USED (parm))
5039 warn_if_shadowing (parm);
5045 /* Take apart the current scope and return a c_arg_info structure with
5046 info on a parameter list just parsed.
5048 This structure is later fed to 'grokparms' and 'store_parm_decls'.
5050 ELLIPSIS being true means the argument list ended in '...' so don't
5051 append a sentinel (void_list_node) to the end of the type-list. */
5054 get_parm_info (bool ellipsis)
5056 struct c_binding *b = current_scope->bindings;
5057 struct c_arg_info *arg_info = XOBNEW (&parser_obstack,
5064 static bool explained_incomplete_types = false;
5065 bool gave_void_only_once_err = false;
5067 arg_info->parms = 0;
5069 arg_info->types = 0;
5070 arg_info->others = 0;
5071 arg_info->pending_sizes = 0;
5072 arg_info->had_vla_unspec = current_scope->had_vla_unspec;
5074 /* The bindings in this scope must not get put into a block.
5075 We will take care of deleting the binding nodes. */
5076 current_scope->bindings = 0;
5078 /* This function is only called if there was *something* on the
5082 /* A parameter list consisting solely of 'void' indicates that the
5083 function takes no arguments. But if the 'void' is qualified
5084 (by 'const' or 'volatile'), or has a storage class specifier
5085 ('register'), then the behavior is undefined; issue an error.
5086 Typedefs for 'void' are OK (see DR#157). */
5087 if (b->prev == 0 /* one binding */
5088 && TREE_CODE (b->decl) == PARM_DECL /* which is a parameter */
5089 && !DECL_NAME (b->decl) /* anonymous */
5090 && VOID_TYPE_P (TREE_TYPE (b->decl))) /* of void type */
5092 if (TREE_THIS_VOLATILE (b->decl)
5093 || TREE_READONLY (b->decl)
5094 || C_DECL_REGISTER (b->decl))
5095 error ("%<void%> as only parameter may not be qualified");
5097 /* There cannot be an ellipsis. */
5099 error ("%<void%> must be the only parameter");
5101 arg_info->types = void_list_node;
5106 types = void_list_node;
5108 /* Break up the bindings list into parms, tags, types, and others;
5109 apply sanity checks; purge the name-to-decl bindings. */
5112 tree decl = b->decl;
5113 tree type = TREE_TYPE (decl);
5114 const char *keyword;
5116 switch (TREE_CODE (decl))
5121 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
5122 I_SYMBOL_BINDING (b->id) = b->shadowed;
5125 /* Check for forward decls that never got their actual decl. */
5126 if (TREE_ASM_WRITTEN (decl))
5127 error ("parameter %q+D has just a forward declaration", decl);
5128 /* Check for (..., void, ...) and issue an error. */
5129 else if (VOID_TYPE_P (type) && !DECL_NAME (decl))
5131 if (!gave_void_only_once_err)
5133 error ("%<void%> must be the only parameter");
5134 gave_void_only_once_err = true;
5139 /* Valid parameter, add it to the list. */
5140 TREE_CHAIN (decl) = parms;
5143 /* Since there is a prototype, args are passed in their
5144 declared types. The back end may override this later. */
5145 DECL_ARG_TYPE (decl) = type;
5146 types = tree_cons (0, type, types);
5150 case ENUMERAL_TYPE: keyword = "enum"; goto tag;
5151 case UNION_TYPE: keyword = "union"; goto tag;
5152 case RECORD_TYPE: keyword = "struct"; goto tag;
5154 /* Types may not have tag-names, in which case the type
5155 appears in the bindings list with b->id NULL. */
5158 gcc_assert (I_TAG_BINDING (b->id) == b);
5159 I_TAG_BINDING (b->id) = b->shadowed;
5162 /* Warn about any struct, union or enum tags defined in a
5163 parameter list. The scope of such types is limited to
5164 the parameter list, which is rarely if ever desirable
5165 (it's impossible to call such a function with type-
5166 correct arguments). An anonymous union parm type is
5167 meaningful as a GNU extension, so don't warn for that. */
5168 if (TREE_CODE (decl) != UNION_TYPE || b->id != 0)
5171 /* The %s will be one of 'struct', 'union', or 'enum'. */
5172 warning (0, "%<%s %E%> declared inside parameter list",
5175 /* The %s will be one of 'struct', 'union', or 'enum'. */
5176 warning (0, "anonymous %s declared inside parameter list",
5179 if (!explained_incomplete_types)
5181 warning (0, "its scope is only this definition or declaration,"
5182 " which is probably not what you want");
5183 explained_incomplete_types = true;
5187 tags = tree_cons (b->id, decl, tags);
5193 /* CONST_DECLs appear here when we have an embedded enum,
5194 and TYPE_DECLs appear here when we have an embedded struct
5195 or union. No warnings for this - we already warned about the
5196 type itself. FUNCTION_DECLs appear when there is an implicit
5197 function declaration in the parameter list. */
5199 TREE_CHAIN (decl) = others;
5204 /* error_mark_node appears here when we have an undeclared
5205 variable. Just throw it away. */
5208 gcc_assert (I_SYMBOL_BINDING (b->id) == b);
5209 I_SYMBOL_BINDING (b->id) = b->shadowed;
5213 /* Other things that might be encountered. */
5220 b = free_binding_and_advance (b);
5223 arg_info->parms = parms;
5224 arg_info->tags = tags;
5225 arg_info->types = types;
5226 arg_info->others = others;
5227 arg_info->pending_sizes = get_pending_sizes ();
5231 /* Get the struct, enum or union (CODE says which) with tag NAME.
5232 Define the tag as a forward-reference if it is not defined.
5233 Return a c_typespec structure for the type specifier. */
5236 parser_xref_tag (enum tree_code code, tree name)
5238 struct c_typespec ret;
5239 /* If a cross reference is requested, look up the type
5240 already defined for this tag and return it. */
5242 tree ref = lookup_tag (code, name, 0);
5243 /* If this is the right type of tag, return what we found.
5244 (This reference will be shadowed by shadow_tag later if appropriate.)
5245 If this is the wrong type of tag, do not return it. If it was the
5246 wrong type in the same scope, we will have had an error
5247 message already; if in a different scope and declaring
5248 a name, pending_xref_error will give an error message; but if in a
5249 different scope and not declaring a name, this tag should
5250 shadow the previous declaration of a different type of tag, and
5251 this would not work properly if we return the reference found.
5252 (For example, with "struct foo" in an outer scope, "union foo;"
5253 must shadow that tag with a new one of union type.) */
5254 ret.kind = (ref ? ctsk_tagref : ctsk_tagfirstref);
5255 if (ref && TREE_CODE (ref) == code)
5261 /* If no such tag is yet defined, create a forward-reference node
5262 and record it as the "definition".
5263 When a real declaration of this type is found,
5264 the forward-reference will be altered into a real type. */
5266 ref = make_node (code);
5267 if (code == ENUMERAL_TYPE)
5269 /* Give the type a default layout like unsigned int
5270 to avoid crashing if it does not get defined. */
5271 TYPE_MODE (ref) = TYPE_MODE (unsigned_type_node);
5272 TYPE_ALIGN (ref) = TYPE_ALIGN (unsigned_type_node);
5273 TYPE_USER_ALIGN (ref) = 0;
5274 TYPE_UNSIGNED (ref) = 1;
5275 TYPE_PRECISION (ref) = TYPE_PRECISION (unsigned_type_node);
5276 TYPE_MIN_VALUE (ref) = TYPE_MIN_VALUE (unsigned_type_node);
5277 TYPE_MAX_VALUE (ref) = TYPE_MAX_VALUE (unsigned_type_node);
5280 pushtag (name, ref);
5286 /* Get the struct, enum or union (CODE says which) with tag NAME.
5287 Define the tag as a forward-reference if it is not defined.
5288 Return a tree for the type. */
5291 xref_tag (enum tree_code code, tree name)
5293 return parser_xref_tag (code, name).spec;
5296 /* Make sure that the tag NAME is defined *in the current scope*
5297 at least as a forward reference.
5298 CODE says which kind of tag NAME ought to be. */
5301 start_struct (enum tree_code code, tree name)
5303 /* If there is already a tag defined at this scope
5304 (as a forward reference), just return it. */
5309 ref = lookup_tag (code, name, 1);
5310 if (ref && TREE_CODE (ref) == code)
5312 if (TYPE_SIZE (ref))
5314 if (code == UNION_TYPE)
5315 error ("redefinition of %<union %E%>", name);
5317 error ("redefinition of %<struct %E%>", name);
5319 else if (C_TYPE_BEING_DEFINED (ref))
5321 if (code == UNION_TYPE)
5322 error ("nested redefinition of %<union %E%>", name);
5324 error ("nested redefinition of %<struct %E%>", name);
5325 /* Don't create structures that contain themselves. */
5330 /* Otherwise create a forward-reference just so the tag is in scope. */
5332 if (ref == NULL_TREE || TREE_CODE (ref) != code)
5334 ref = make_node (code);
5335 pushtag (name, ref);
5338 C_TYPE_BEING_DEFINED (ref) = 1;
5339 TYPE_PACKED (ref) = flag_pack_struct;
5343 /* Process the specs, declarator and width (NULL if omitted)
5344 of a structure component, returning a FIELD_DECL node.
5345 WIDTH is non-NULL for bit-fields only, and is an INTEGER_CST node.
5346 DECL_ATTRS is as for grokdeclarator.
5348 This is done during the parsing of the struct declaration.
5349 The FIELD_DECL nodes are chained together and the lot of them
5350 are ultimately passed to `build_struct' to make the RECORD_TYPE node. */
5353 grokfield (struct c_declarator *declarator, struct c_declspecs *declspecs,
5354 tree width, tree *decl_attrs)
5358 if (declarator->kind == cdk_id && declarator->u.id == NULL_TREE
5359 && width == NULL_TREE)
5361 /* This is an unnamed decl.
5363 If we have something of the form "union { list } ;" then this
5364 is the anonymous union extension. Similarly for struct.
5366 If this is something of the form "struct foo;", then
5367 If MS extensions are enabled, this is handled as an
5369 Otherwise this is a forward declaration of a structure tag.
5371 If this is something of the form "foo;" and foo is a TYPE_DECL, then
5372 If MS extensions are enabled and foo names a structure, then
5373 again this is an anonymous struct.
5374 Otherwise this is an error.
5376 Oh what a horrid tangled web we weave. I wonder if MS consciously
5377 took this from Plan 9 or if it was an accident of implementation
5378 that took root before someone noticed the bug... */
5380 tree type = declspecs->type;
5381 bool type_ok = (TREE_CODE (type) == RECORD_TYPE
5382 || TREE_CODE (type) == UNION_TYPE);
5386 && (flag_ms_extensions || !declspecs->typedef_p))
5388 if (flag_ms_extensions)
5392 else if (TYPE_NAME (type) == NULL)
5399 pedwarn (0, "declaration does not declare anything");
5402 pedwarn (OPT_pedantic, "ISO C doesn%'t support unnamed structs/unions");
5405 value = grokdeclarator (declarator, declspecs, FIELD, false,
5406 width ? &width : NULL, decl_attrs,
5409 finish_decl (value, NULL_TREE, NULL_TREE);
5410 DECL_INITIAL (value) = width;
5415 /* Generate an error for any duplicate field names in FIELDLIST. Munge
5416 the list such that this does not present a problem later. */
5419 detect_field_duplicates (tree fieldlist)
5424 /* First, see if there are more than "a few" fields.
5425 This is trivially true if there are zero or one fields. */
5428 x = TREE_CHAIN (fieldlist);
5434 } while (timeout > 0 && x);
5436 /* If there were "few" fields, avoid the overhead of allocating
5437 a hash table. Instead just do the nested traversal thing. */
5440 for (x = TREE_CHAIN (fieldlist); x ; x = TREE_CHAIN (x))
5443 for (y = fieldlist; y != x; y = TREE_CHAIN (y))
5444 if (DECL_NAME (y) == DECL_NAME (x))
5446 error ("duplicate member %q+D", x);
5447 DECL_NAME (x) = NULL_TREE;
5453 htab_t htab = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL);
5456 for (x = fieldlist; x ; x = TREE_CHAIN (x))
5457 if ((y = DECL_NAME (x)) != 0)
5459 slot = htab_find_slot (htab, y, INSERT);
5462 error ("duplicate member %q+D", x);
5463 DECL_NAME (x) = NULL_TREE;
5472 /* Fill in the fields of a RECORD_TYPE or UNION_TYPE node, T.
5473 FIELDLIST is a chain of FIELD_DECL nodes for the fields.
5474 ATTRIBUTES are attributes to be applied to the structure. */
5477 finish_struct (tree t, tree fieldlist, tree attributes)
5480 bool toplevel = file_scope == current_scope;
5481 int saw_named_field;
5483 /* If this type was previously laid out as a forward reference,
5484 make sure we lay it out again. */
5488 decl_attributes (&t, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5492 for (x = fieldlist; x; x = TREE_CHAIN (x))
5493 if (DECL_NAME (x) != 0)
5498 if (TREE_CODE (t) == UNION_TYPE)
5501 pedwarn (OPT_pedantic, "union has no named members");
5503 pedwarn (OPT_pedantic, "union has no members");
5508 pedwarn (OPT_pedantic, "struct has no named members");
5510 pedwarn (OPT_pedantic, "struct has no members");
5515 /* Install struct as DECL_CONTEXT of each field decl.
5516 Also process specified field sizes, found in the DECL_INITIAL,
5517 storing 0 there after the type has been changed to precision equal
5518 to its width, rather than the precision of the specified standard
5519 type. (Correct layout requires the original type to have been preserved
5522 saw_named_field = 0;
5523 for (x = fieldlist; x; x = TREE_CHAIN (x))
5525 if (TREE_TYPE (x) == error_mark_node)
5528 DECL_CONTEXT (x) = t;
5530 if (TYPE_PACKED (t) && TYPE_ALIGN (TREE_TYPE (x)) > BITS_PER_UNIT)
5531 DECL_PACKED (x) = 1;
5533 /* If any field is const, the structure type is pseudo-const. */
5534 if (TREE_READONLY (x))
5535 C_TYPE_FIELDS_READONLY (t) = 1;
5538 /* A field that is pseudo-const makes the structure likewise. */
5539 tree t1 = TREE_TYPE (x);
5540 while (TREE_CODE (t1) == ARRAY_TYPE)
5541 t1 = TREE_TYPE (t1);
5542 if ((TREE_CODE (t1) == RECORD_TYPE || TREE_CODE (t1) == UNION_TYPE)
5543 && C_TYPE_FIELDS_READONLY (t1))
5544 C_TYPE_FIELDS_READONLY (t) = 1;
5547 /* Any field that is volatile means variables of this type must be
5548 treated in some ways as volatile. */
5549 if (TREE_THIS_VOLATILE (x))
5550 C_TYPE_FIELDS_VOLATILE (t) = 1;
5552 /* Any field of nominal variable size implies structure is too. */
5553 if (C_DECL_VARIABLE_SIZE (x))
5554 C_TYPE_VARIABLE_SIZE (t) = 1;
5556 if (DECL_INITIAL (x))
5558 unsigned HOST_WIDE_INT width = tree_low_cst (DECL_INITIAL (x), 1);
5559 DECL_SIZE (x) = bitsize_int (width);
5560 DECL_BIT_FIELD (x) = 1;
5561 SET_DECL_C_BIT_FIELD (x);
5564 /* Detect flexible array member in an invalid context. */
5565 if (TREE_CODE (TREE_TYPE (x)) == ARRAY_TYPE
5566 && TYPE_SIZE (TREE_TYPE (x)) == NULL_TREE
5567 && TYPE_DOMAIN (TREE_TYPE (x)) != NULL_TREE
5568 && TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (x))) == NULL_TREE)
5570 if (TREE_CODE (t) == UNION_TYPE)
5572 error ("%Jflexible array member in union", x);
5573 TREE_TYPE (x) = error_mark_node;
5575 else if (TREE_CHAIN (x) != NULL_TREE)
5577 error ("%Jflexible array member not at end of struct", x);
5578 TREE_TYPE (x) = error_mark_node;
5580 else if (!saw_named_field)
5582 error ("%Jflexible array member in otherwise empty struct", x);
5583 TREE_TYPE (x) = error_mark_node;
5587 if (pedantic && !in_system_header && TREE_CODE (t) == RECORD_TYPE
5588 && flexible_array_type_p (TREE_TYPE (x)))
5589 pedwarn (OPT_pedantic,
5590 "%Jinvalid use of structure with flexible array member", x);
5593 saw_named_field = 1;
5596 detect_field_duplicates (fieldlist);
5598 /* Now we have the nearly final fieldlist. Record it,
5599 then lay out the structure or union (including the fields). */
5601 TYPE_FIELDS (t) = fieldlist;
5605 /* Give bit-fields their proper types. */
5607 tree *fieldlistp = &fieldlist;
5609 if (TREE_CODE (*fieldlistp) == FIELD_DECL && DECL_INITIAL (*fieldlistp)
5610 && TREE_TYPE (*fieldlistp) != error_mark_node)
5612 unsigned HOST_WIDE_INT width
5613 = tree_low_cst (DECL_INITIAL (*fieldlistp), 1);
5614 tree type = TREE_TYPE (*fieldlistp);
5615 if (width != TYPE_PRECISION (type))
5617 TREE_TYPE (*fieldlistp)
5618 = c_build_bitfield_integer_type (width, TYPE_UNSIGNED (type));
5619 DECL_MODE (*fieldlistp) = TYPE_MODE (TREE_TYPE (*fieldlistp));
5621 DECL_INITIAL (*fieldlistp) = 0;
5624 fieldlistp = &TREE_CHAIN (*fieldlistp);
5627 /* Now we have the truly final field list.
5628 Store it in this type and in the variants. */
5630 TYPE_FIELDS (t) = fieldlist;
5632 /* If there are lots of fields, sort so we can look through them fast.
5633 We arbitrarily consider 16 or more elts to be "a lot". */
5638 for (x = fieldlist; x; x = TREE_CHAIN (x))
5640 if (len > 15 || DECL_NAME (x) == NULL)
5648 struct lang_type *space;
5649 struct sorted_fields_type *space2;
5651 len += list_length (x);
5653 /* Use the same allocation policy here that make_node uses, to
5654 ensure that this lives as long as the rest of the struct decl.
5655 All decls in an inline function need to be saved. */
5657 space = GGC_CNEW (struct lang_type);
5658 space2 = GGC_NEWVAR (struct sorted_fields_type,
5659 sizeof (struct sorted_fields_type) + len * sizeof (tree));
5663 field_array = &space2->elts[0];
5664 for (x = fieldlist; x; x = TREE_CHAIN (x))
5666 field_array[len++] = x;
5668 /* If there is anonymous struct or union, break out of the loop. */
5669 if (DECL_NAME (x) == NULL)
5672 /* Found no anonymous struct/union. Add the TYPE_LANG_SPECIFIC. */
5675 TYPE_LANG_SPECIFIC (t) = space;
5676 TYPE_LANG_SPECIFIC (t)->s->len = len;
5677 field_array = TYPE_LANG_SPECIFIC (t)->s->elts;
5678 qsort (field_array, len, sizeof (tree), field_decl_cmp);
5683 for (x = TYPE_MAIN_VARIANT (t); x; x = TYPE_NEXT_VARIANT (x))
5685 TYPE_FIELDS (x) = TYPE_FIELDS (t);
5686 TYPE_LANG_SPECIFIC (x) = TYPE_LANG_SPECIFIC (t);
5687 C_TYPE_FIELDS_READONLY (x) = C_TYPE_FIELDS_READONLY (t);
5688 C_TYPE_FIELDS_VOLATILE (x) = C_TYPE_FIELDS_VOLATILE (t);
5689 C_TYPE_VARIABLE_SIZE (x) = C_TYPE_VARIABLE_SIZE (t);
5692 /* If this was supposed to be a transparent union, but we can't
5693 make it one, warn and turn off the flag. */
5694 if (TREE_CODE (t) == UNION_TYPE
5695 && TYPE_TRANSPARENT_UNION (t)
5696 && (!TYPE_FIELDS (t) || TYPE_MODE (t) != DECL_MODE (TYPE_FIELDS (t))))
5698 TYPE_TRANSPARENT_UNION (t) = 0;
5699 warning (0, "union cannot be made transparent");
5702 /* If this structure or union completes the type of any previous
5703 variable declaration, lay it out and output its rtl. */
5704 for (x = C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t));
5708 tree decl = TREE_VALUE (x);
5709 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
5710 layout_array_type (TREE_TYPE (decl));
5711 if (TREE_CODE (decl) != TYPE_DECL)
5713 layout_decl (decl, 0);
5714 if (c_dialect_objc ())
5715 objc_check_decl (decl);
5716 rest_of_decl_compilation (decl, toplevel, 0);
5721 C_TYPE_INCOMPLETE_VARS (TYPE_MAIN_VARIANT (t)) = 0;
5723 /* Finish debugging output for this type. */
5724 rest_of_type_compilation (t, toplevel);
5726 /* If we're inside a function proper, i.e. not file-scope and not still
5727 parsing parameters, then arrange for the size of a variable sized type
5729 if (cur_stmt_list && variably_modified_type_p (t, NULL_TREE))
5730 add_stmt (build_stmt (DECL_EXPR, build_decl (TYPE_DECL, NULL, t)));
5735 /* Lay out the type T, and its element type, and so on. */
5738 layout_array_type (tree t)
5740 if (TREE_CODE (TREE_TYPE (t)) == ARRAY_TYPE)
5741 layout_array_type (TREE_TYPE (t));
5745 /* Begin compiling the definition of an enumeration type.
5746 NAME is its name (or null if anonymous).
5747 Returns the type object, as yet incomplete.
5748 Also records info about it so that build_enumerator
5749 may be used to declare the individual values as they are read. */
5752 start_enum (struct c_enum_contents *the_enum, tree name)
5756 /* If this is the real definition for a previous forward reference,
5757 fill in the contents in the same object that used to be the
5758 forward reference. */
5761 enumtype = lookup_tag (ENUMERAL_TYPE, name, 1);
5763 if (enumtype == 0 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
5765 enumtype = make_node (ENUMERAL_TYPE);
5766 pushtag (name, enumtype);
5769 if (C_TYPE_BEING_DEFINED (enumtype))
5770 error ("nested redefinition of %<enum %E%>", name);
5772 C_TYPE_BEING_DEFINED (enumtype) = 1;
5774 if (TYPE_VALUES (enumtype) != 0)
5776 /* This enum is a named one that has been declared already. */
5777 error ("redeclaration of %<enum %E%>", name);
5779 /* Completely replace its old definition.
5780 The old enumerators remain defined, however. */
5781 TYPE_VALUES (enumtype) = 0;
5784 the_enum->enum_next_value = integer_zero_node;
5785 the_enum->enum_overflow = 0;
5787 if (flag_short_enums)
5788 TYPE_PACKED (enumtype) = 1;
5793 /* After processing and defining all the values of an enumeration type,
5794 install their decls in the enumeration type and finish it off.
5795 ENUMTYPE is the type object, VALUES a list of decl-value pairs,
5796 and ATTRIBUTES are the specified attributes.
5797 Returns ENUMTYPE. */
5800 finish_enum (tree enumtype, tree values, tree attributes)
5803 tree minnode = 0, maxnode = 0;
5804 int precision, unsign;
5805 bool toplevel = (file_scope == current_scope);
5806 struct lang_type *lt;
5808 decl_attributes (&enumtype, attributes, (int) ATTR_FLAG_TYPE_IN_PLACE);
5810 /* Calculate the maximum value of any enumerator in this type. */
5812 if (values == error_mark_node)
5813 minnode = maxnode = integer_zero_node;
5816 minnode = maxnode = TREE_VALUE (values);
5817 for (pair = TREE_CHAIN (values); pair; pair = TREE_CHAIN (pair))
5819 tree value = TREE_VALUE (pair);
5820 if (tree_int_cst_lt (maxnode, value))
5822 if (tree_int_cst_lt (value, minnode))
5827 /* Construct the final type of this enumeration. It is the same
5828 as one of the integral types - the narrowest one that fits, except
5829 that normally we only go as narrow as int - and signed iff any of
5830 the values are negative. */
5831 unsign = (tree_int_cst_sgn (minnode) >= 0);
5832 precision = MAX (min_precision (minnode, unsign),
5833 min_precision (maxnode, unsign));
5835 if (TYPE_PACKED (enumtype) || precision > TYPE_PRECISION (integer_type_node))
5837 tem = c_common_type_for_size (precision, unsign);
5840 warning (0, "enumeration values exceed range of largest integer");
5841 tem = long_long_integer_type_node;
5845 tem = unsign ? unsigned_type_node : integer_type_node;
5847 TYPE_MIN_VALUE (enumtype) = TYPE_MIN_VALUE (tem);
5848 TYPE_MAX_VALUE (enumtype) = TYPE_MAX_VALUE (tem);
5849 TYPE_UNSIGNED (enumtype) = TYPE_UNSIGNED (tem);
5850 TYPE_SIZE (enumtype) = 0;
5852 /* If the precision of the type was specific with an attribute and it
5853 was too small, give an error. Otherwise, use it. */
5854 if (TYPE_PRECISION (enumtype))
5856 if (precision > TYPE_PRECISION (enumtype))
5857 error ("specified mode too small for enumeral values");
5860 TYPE_PRECISION (enumtype) = TYPE_PRECISION (tem);
5862 layout_type (enumtype);
5864 if (values != error_mark_node)
5866 /* Change the type of the enumerators to be the enum type. We
5867 need to do this irrespective of the size of the enum, for
5868 proper type checking. Replace the DECL_INITIALs of the
5869 enumerators, and the value slots of the list, with copies
5870 that have the enum type; they cannot be modified in place
5871 because they may be shared (e.g. integer_zero_node) Finally,
5872 change the purpose slots to point to the names of the decls. */
5873 for (pair = values; pair; pair = TREE_CHAIN (pair))
5875 tree enu = TREE_PURPOSE (pair);
5876 tree ini = DECL_INITIAL (enu);
5878 TREE_TYPE (enu) = enumtype;
5880 /* The ISO C Standard mandates enumerators to have type int,
5881 even though the underlying type of an enum type is
5882 unspecified. Here we convert any enumerators that fit in
5883 an int to type int, to avoid promotions to unsigned types
5884 when comparing integers with enumerators that fit in the
5885 int range. When -pedantic is given, build_enumerator()
5886 would have already taken care of those that don't fit. */
5887 if (int_fits_type_p (ini, integer_type_node))
5888 tem = integer_type_node;
5891 ini = convert (tem, ini);
5893 DECL_INITIAL (enu) = ini;
5894 TREE_PURPOSE (pair) = DECL_NAME (enu);
5895 TREE_VALUE (pair) = ini;
5898 TYPE_VALUES (enumtype) = values;
5901 /* Record the min/max values so that we can warn about bit-field
5902 enumerations that are too small for the values. */
5903 lt = GGC_CNEW (struct lang_type);
5904 lt->enum_min = minnode;
5905 lt->enum_max = maxnode;
5906 TYPE_LANG_SPECIFIC (enumtype) = lt;
5908 /* Fix up all variant types of this enum type. */
5909 for (tem = TYPE_MAIN_VARIANT (enumtype); tem; tem = TYPE_NEXT_VARIANT (tem))
5911 if (tem == enumtype)
5913 TYPE_VALUES (tem) = TYPE_VALUES (enumtype);
5914 TYPE_MIN_VALUE (tem) = TYPE_MIN_VALUE (enumtype);
5915 TYPE_MAX_VALUE (tem) = TYPE_MAX_VALUE (enumtype);
5916 TYPE_SIZE (tem) = TYPE_SIZE (enumtype);
5917 TYPE_SIZE_UNIT (tem) = TYPE_SIZE_UNIT (enumtype);
5918 TYPE_MODE (tem) = TYPE_MODE (enumtype);
5919 TYPE_PRECISION (tem) = TYPE_PRECISION (enumtype);
5920 TYPE_ALIGN (tem) = TYPE_ALIGN (enumtype);
5921 TYPE_USER_ALIGN (tem) = TYPE_USER_ALIGN (enumtype);
5922 TYPE_UNSIGNED (tem) = TYPE_UNSIGNED (enumtype);
5923 TYPE_LANG_SPECIFIC (tem) = TYPE_LANG_SPECIFIC (enumtype);
5926 /* Finish debugging output for this type. */
5927 rest_of_type_compilation (enumtype, toplevel);
5932 /* Build and install a CONST_DECL for one value of the
5933 current enumeration type (one that was begun with start_enum).
5934 Return a tree-list containing the CONST_DECL and its value.
5935 Assignment of sequential values by default is handled here. */
5938 build_enumerator (struct c_enum_contents *the_enum, tree name, tree value)
5942 /* Validate and default VALUE. */
5946 /* Don't issue more errors for error_mark_node (i.e. an
5947 undeclared identifier) - just ignore the value expression. */
5948 if (value == error_mark_node)
5950 else if (!INTEGRAL_TYPE_P (TREE_TYPE (value))
5951 || TREE_CODE (value) != INTEGER_CST)
5953 error ("enumerator value for %qE is not an integer constant", name);
5958 value = default_conversion (value);
5959 constant_expression_warning (value);
5963 /* Default based on previous value. */
5964 /* It should no longer be possible to have NON_LVALUE_EXPR
5968 value = the_enum->enum_next_value;
5969 if (the_enum->enum_overflow)
5970 error ("overflow in enumeration values");
5973 if (pedantic && !int_fits_type_p (value, integer_type_node))
5975 pedwarn (OPT_pedantic, "ISO C restricts enumerator values to range of %<int%>");
5976 /* XXX This causes -pedantic to change the meaning of the program.
5977 Remove? -zw 2004-03-15 */
5978 value = convert (integer_type_node, value);
5981 /* Set basis for default for next value. */
5982 the_enum->enum_next_value = build_binary_op (PLUS_EXPR, value,
5983 integer_one_node, 0);
5984 the_enum->enum_overflow = tree_int_cst_lt (the_enum->enum_next_value, value);
5986 /* Now create a declaration for the enum value name. */
5988 type = TREE_TYPE (value);
5989 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
5990 TYPE_PRECISION (integer_type_node)),
5991 (TYPE_PRECISION (type)
5992 >= TYPE_PRECISION (integer_type_node)
5993 && TYPE_UNSIGNED (type)));
5995 decl = build_decl (CONST_DECL, name, type);
5996 DECL_INITIAL (decl) = convert (type, value);
5999 return tree_cons (decl, value, NULL_TREE);
6003 /* Create the FUNCTION_DECL for a function definition.
6004 DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of
6005 the declaration; they describe the function's name and the type it returns,
6006 but twisted together in a fashion that parallels the syntax of C.
6008 This function creates a binding context for the function body
6009 as well as setting up the FUNCTION_DECL in current_function_decl.
6011 Returns 1 on success. If the DECLARATOR is not suitable for a function
6012 (it defines a datum instead), we return 0, which tells
6013 yyparse to report a parse error. */
6016 start_function (struct c_declspecs *declspecs, struct c_declarator *declarator,
6019 tree decl1, old_decl;
6020 tree restype, resdecl;
6021 struct c_label_context_se *nstack_se;
6022 struct c_label_context_vm *nstack_vm;
6024 current_function_returns_value = 0; /* Assume, until we see it does. */
6025 current_function_returns_null = 0;
6026 current_function_returns_abnormally = 0;
6027 warn_about_return_type = 0;
6028 c_switch_stack = NULL;
6030 nstack_se = XOBNEW (&parser_obstack, struct c_label_context_se);
6031 nstack_se->labels_def = NULL;
6032 nstack_se->labels_used = NULL;
6033 nstack_se->next = label_context_stack_se;
6034 label_context_stack_se = nstack_se;
6036 nstack_vm = XOBNEW (&parser_obstack, struct c_label_context_vm);
6037 nstack_vm->labels_def = NULL;
6038 nstack_vm->labels_used = NULL;
6039 nstack_vm->scope = 0;
6040 nstack_vm->next = label_context_stack_vm;
6041 label_context_stack_vm = nstack_vm;
6043 /* Indicate no valid break/continue context by setting these variables
6044 to some non-null, non-label value. We'll notice and emit the proper
6045 error message in c_finish_bc_stmt. */
6046 c_break_label = c_cont_label = size_zero_node;
6048 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, true, NULL,
6049 &attributes, DEPRECATED_NORMAL);
6051 /* If the declarator is not suitable for a function definition,
6052 cause a syntax error. */
6055 label_context_stack_se = label_context_stack_se->next;
6056 label_context_stack_vm = label_context_stack_vm->next;
6060 decl_attributes (&decl1, attributes, 0);
6062 if (DECL_DECLARED_INLINE_P (decl1)
6063 && DECL_UNINLINABLE (decl1)
6064 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl1)))
6065 warning (OPT_Wattributes, "inline function %q+D given attribute noinline",
6068 /* Handle gnu_inline attribute. */
6069 if (declspecs->inline_p
6070 && !flag_gnu89_inline
6071 && TREE_CODE (decl1) == FUNCTION_DECL
6072 && (lookup_attribute ("gnu_inline", DECL_ATTRIBUTES (decl1))
6073 || current_function_decl))
6075 if (declspecs->storage_class != csc_static)
6076 DECL_EXTERNAL (decl1) = !DECL_EXTERNAL (decl1);
6079 announce_function (decl1);
6081 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl1))))
6083 error ("return type is an incomplete type");
6084 /* Make it return void instead. */
6086 = build_function_type (void_type_node,
6087 TYPE_ARG_TYPES (TREE_TYPE (decl1)));
6090 if (warn_about_return_type)
6091 pedwarn_c99 (flag_isoc99 ? 0
6092 : (warn_return_type ? OPT_Wreturn_type : OPT_Wimplicit_int),
6093 "return type defaults to %<int%>");
6095 /* Make the init_value nonzero so pushdecl knows this is not tentative.
6096 error_mark_node is replaced below (in pop_scope) with the BLOCK. */
6097 DECL_INITIAL (decl1) = error_mark_node;
6099 /* If this definition isn't a prototype and we had a prototype declaration
6100 before, copy the arg type info from that prototype. */
6101 old_decl = lookup_name_in_scope (DECL_NAME (decl1), current_scope);
6102 if (old_decl && TREE_CODE (old_decl) != FUNCTION_DECL)
6104 current_function_prototype_locus = UNKNOWN_LOCATION;
6105 current_function_prototype_built_in = false;
6106 current_function_prototype_arg_types = NULL_TREE;
6107 if (TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0)
6109 if (old_decl != 0 && TREE_CODE (TREE_TYPE (old_decl)) == FUNCTION_TYPE
6110 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
6111 TREE_TYPE (TREE_TYPE (old_decl))))
6113 TREE_TYPE (decl1) = composite_type (TREE_TYPE (old_decl),
6115 current_function_prototype_locus = DECL_SOURCE_LOCATION (old_decl);
6116 current_function_prototype_built_in
6117 = C_DECL_BUILTIN_PROTOTYPE (old_decl);
6118 current_function_prototype_arg_types
6119 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
6121 if (TREE_PUBLIC (decl1))
6123 /* If there is an external prototype declaration of this
6124 function, record its location but do not copy information
6125 to this decl. This may be an invisible declaration
6126 (built-in or in a scope which has finished) or simply
6127 have more refined argument types than any declaration
6129 struct c_binding *b;
6130 for (b = I_SYMBOL_BINDING (DECL_NAME (decl1)); b; b = b->shadowed)
6131 if (B_IN_SCOPE (b, external_scope))
6135 tree ext_decl, ext_type;
6137 ext_type = b->type ? b->type : TREE_TYPE (ext_decl);
6138 if (TREE_CODE (ext_type) == FUNCTION_TYPE
6139 && comptypes (TREE_TYPE (TREE_TYPE (decl1)),
6140 TREE_TYPE (ext_type)))
6142 current_function_prototype_locus
6143 = DECL_SOURCE_LOCATION (ext_decl);
6144 current_function_prototype_built_in
6145 = C_DECL_BUILTIN_PROTOTYPE (ext_decl);
6146 current_function_prototype_arg_types
6147 = TYPE_ARG_TYPES (ext_type);
6153 /* Optionally warn of old-fashioned def with no previous prototype. */
6154 if (warn_strict_prototypes
6155 && old_decl != error_mark_node
6156 && TYPE_ARG_TYPES (TREE_TYPE (decl1)) == 0
6157 && C_DECL_ISNT_PROTOTYPE (old_decl))
6158 warning (OPT_Wstrict_prototypes,
6159 "function declaration isn%'t a prototype");
6160 /* Optionally warn of any global def with no previous prototype. */
6161 else if (warn_missing_prototypes
6162 && old_decl != error_mark_node
6163 && TREE_PUBLIC (decl1)
6164 && !MAIN_NAME_P (DECL_NAME (decl1))
6165 && C_DECL_ISNT_PROTOTYPE (old_decl))
6166 warning (OPT_Wmissing_prototypes, "no previous prototype for %q+D", decl1);
6167 /* Optionally warn of any def with no previous prototype
6168 if the function has already been used. */
6169 else if (warn_missing_prototypes
6171 && old_decl != error_mark_node
6172 && TREE_USED (old_decl)
6173 && TYPE_ARG_TYPES (TREE_TYPE (old_decl)) == 0)
6174 warning (OPT_Wmissing_prototypes,
6175 "%q+D was used with no prototype before its definition", decl1);
6176 /* Optionally warn of any global def with no previous declaration. */
6177 else if (warn_missing_declarations
6178 && TREE_PUBLIC (decl1)
6180 && !MAIN_NAME_P (DECL_NAME (decl1)))
6181 warning (OPT_Wmissing_declarations, "no previous declaration for %q+D",
6183 /* Optionally warn of any def with no previous declaration
6184 if the function has already been used. */
6185 else if (warn_missing_declarations
6187 && old_decl != error_mark_node
6188 && TREE_USED (old_decl)
6189 && C_DECL_IMPLICIT (old_decl))
6190 warning (OPT_Wmissing_declarations,
6191 "%q+D was used with no declaration before its definition", decl1);
6193 /* This function exists in static storage.
6194 (This does not mean `static' in the C sense!) */
6195 TREE_STATIC (decl1) = 1;
6197 /* A nested function is not global. */
6198 if (current_function_decl != 0)
6199 TREE_PUBLIC (decl1) = 0;
6201 /* This is the earliest point at which we might know the assembler
6202 name of the function. Thus, if it's set before this, die horribly. */
6203 gcc_assert (!DECL_ASSEMBLER_NAME_SET_P (decl1));
6205 /* If #pragma weak was used, mark the decl weak now. */
6206 if (current_scope == file_scope)
6207 maybe_apply_pragma_weak (decl1);
6209 /* Warn for unlikely, improbable, or stupid declarations of `main'. */
6210 if (warn_main > 0 && MAIN_NAME_P (DECL_NAME (decl1)))
6212 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (decl1)))
6213 != integer_type_node)
6214 pedwarn (OPT_Wmain, "return type of %q+D is not %<int%>", decl1);
6216 check_main_parameter_types(decl1);
6218 if (!TREE_PUBLIC (decl1))
6219 pedwarn (OPT_Wmain, "%q+D is normally a non-static function", decl1);
6222 /* Record the decl so that the function name is defined.
6223 If we already have a decl for this name, and it is a FUNCTION_DECL,
6224 use the old decl. */
6226 current_function_decl = pushdecl (decl1);
6229 declare_parm_level ();
6231 restype = TREE_TYPE (TREE_TYPE (current_function_decl));
6232 resdecl = build_decl (RESULT_DECL, NULL_TREE, restype);
6233 DECL_ARTIFICIAL (resdecl) = 1;
6234 DECL_IGNORED_P (resdecl) = 1;
6235 DECL_RESULT (current_function_decl) = resdecl;
6237 start_fname_decls ();
6242 /* Subroutine of store_parm_decls which handles new-style function
6243 definitions (prototype format). The parms already have decls, so we
6244 need only record them as in effect and complain if any redundant
6245 old-style parm decls were written. */
6247 store_parm_decls_newstyle (tree fndecl, const struct c_arg_info *arg_info)
6251 if (current_scope->bindings)
6253 error ("%Jold-style parameter declarations in prototyped "
6254 "function definition", fndecl);
6256 /* Get rid of the old-style declarations. */
6260 /* Don't issue this warning for nested functions, and don't issue this
6261 warning if we got here because ARG_INFO_TYPES was error_mark_node
6262 (this happens when a function definition has just an ellipsis in
6263 its parameter list). */
6264 else if (!in_system_header && !current_function_scope
6265 && arg_info->types != error_mark_node)
6266 warning (OPT_Wtraditional,
6267 "%Jtraditional C rejects ISO C style function definitions",
6270 /* Now make all the parameter declarations visible in the function body.
6271 We can bypass most of the grunt work of pushdecl. */
6272 for (decl = arg_info->parms; decl; decl = TREE_CHAIN (decl))
6274 DECL_CONTEXT (decl) = current_function_decl;
6275 if (DECL_NAME (decl))
6277 bind (DECL_NAME (decl), decl, current_scope,
6278 /*invisible=*/false, /*nested=*/false);
6279 if (!TREE_USED (decl))
6280 warn_if_shadowing (decl);
6283 error ("%Jparameter name omitted", decl);
6286 /* Record the parameter list in the function declaration. */
6287 DECL_ARGUMENTS (fndecl) = arg_info->parms;
6289 /* Now make all the ancillary declarations visible, likewise. */
6290 for (decl = arg_info->others; decl; decl = TREE_CHAIN (decl))
6292 DECL_CONTEXT (decl) = current_function_decl;
6293 if (DECL_NAME (decl))
6294 bind (DECL_NAME (decl), decl, current_scope,
6295 /*invisible=*/false, /*nested=*/false);
6298 /* And all the tag declarations. */
6299 for (decl = arg_info->tags; decl; decl = TREE_CHAIN (decl))
6300 if (TREE_PURPOSE (decl))
6301 bind (TREE_PURPOSE (decl), TREE_VALUE (decl), current_scope,
6302 /*invisible=*/false, /*nested=*/false);
6305 /* Subroutine of store_parm_decls which handles old-style function
6306 definitions (separate parameter list and declarations). */
6309 store_parm_decls_oldstyle (tree fndecl, const struct c_arg_info *arg_info)
6311 struct c_binding *b;
6312 tree parm, decl, last;
6313 tree parmids = arg_info->parms;
6314 struct pointer_set_t *seen_args = pointer_set_create ();
6316 if (!in_system_header)
6317 warning (OPT_Wold_style_definition, "%Jold-style function definition",
6320 /* Match each formal parameter name with its declaration. Save each
6321 decl in the appropriate TREE_PURPOSE slot of the parmids chain. */
6322 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6324 if (TREE_VALUE (parm) == 0)
6326 error ("%Jparameter name missing from parameter list", fndecl);
6327 TREE_PURPOSE (parm) = 0;
6331 b = I_SYMBOL_BINDING (TREE_VALUE (parm));
6332 if (b && B_IN_CURRENT_SCOPE (b))
6335 /* If we got something other than a PARM_DECL it is an error. */
6336 if (TREE_CODE (decl) != PARM_DECL)
6337 error ("%q+D declared as a non-parameter", decl);
6338 /* If the declaration is already marked, we have a duplicate
6339 name. Complain and ignore the duplicate. */
6340 else if (pointer_set_contains (seen_args, decl))
6342 error ("multiple parameters named %q+D", decl);
6343 TREE_PURPOSE (parm) = 0;
6346 /* If the declaration says "void", complain and turn it into
6348 else if (VOID_TYPE_P (TREE_TYPE (decl)))
6350 error ("parameter %q+D declared with void type", decl);
6351 TREE_TYPE (decl) = integer_type_node;
6352 DECL_ARG_TYPE (decl) = integer_type_node;
6353 layout_decl (decl, 0);
6355 warn_if_shadowing (decl);
6357 /* If no declaration found, default to int. */
6360 decl = build_decl (PARM_DECL, TREE_VALUE (parm), integer_type_node);
6361 DECL_ARG_TYPE (decl) = TREE_TYPE (decl);
6362 DECL_SOURCE_LOCATION (decl) = DECL_SOURCE_LOCATION (fndecl);
6364 warn_if_shadowing (decl);
6367 pedwarn (0, "type of %q+D defaults to %<int%>", decl);
6369 warning (OPT_Wmissing_parameter_type, "type of %q+D defaults to %<int%>", decl);
6372 TREE_PURPOSE (parm) = decl;
6373 pointer_set_insert (seen_args, decl);
6376 /* Now examine the parms chain for incomplete declarations
6377 and declarations with no corresponding names. */
6379 for (b = current_scope->bindings; b; b = b->prev)
6382 if (TREE_CODE (parm) != PARM_DECL)
6385 if (TREE_TYPE (parm) != error_mark_node
6386 && !COMPLETE_TYPE_P (TREE_TYPE (parm)))
6388 error ("parameter %q+D has incomplete type", parm);
6389 TREE_TYPE (parm) = error_mark_node;
6392 if (!pointer_set_contains (seen_args, parm))
6394 error ("declaration for parameter %q+D but no such parameter", parm);
6396 /* Pretend the parameter was not missing.
6397 This gets us to a standard state and minimizes
6398 further error messages. */
6399 parmids = chainon (parmids, tree_cons (parm, 0, 0));
6403 /* Chain the declarations together in the order of the list of
6404 names. Store that chain in the function decl, replacing the
6405 list of names. Update the current scope to match. */
6406 DECL_ARGUMENTS (fndecl) = 0;
6408 for (parm = parmids; parm; parm = TREE_CHAIN (parm))
6409 if (TREE_PURPOSE (parm))
6411 if (parm && TREE_PURPOSE (parm))
6413 last = TREE_PURPOSE (parm);
6414 DECL_ARGUMENTS (fndecl) = last;
6416 for (parm = TREE_CHAIN (parm); parm; parm = TREE_CHAIN (parm))
6417 if (TREE_PURPOSE (parm))
6419 TREE_CHAIN (last) = TREE_PURPOSE (parm);
6420 last = TREE_PURPOSE (parm);
6422 TREE_CHAIN (last) = 0;
6425 pointer_set_destroy (seen_args);
6427 /* If there was a previous prototype,
6428 set the DECL_ARG_TYPE of each argument according to
6429 the type previously specified, and report any mismatches. */
6431 if (current_function_prototype_arg_types)
6434 for (parm = DECL_ARGUMENTS (fndecl),
6435 type = current_function_prototype_arg_types;
6436 parm || (type && TREE_VALUE (type) != error_mark_node
6437 && (TYPE_MAIN_VARIANT (TREE_VALUE (type)) != void_type_node));
6438 parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
6440 if (parm == 0 || type == 0
6441 || TYPE_MAIN_VARIANT (TREE_VALUE (type)) == void_type_node)
6443 if (current_function_prototype_built_in)
6444 warning (0, "number of arguments doesn%'t match "
6445 "built-in prototype");
6448 error ("number of arguments doesn%'t match prototype");
6449 error ("%Hprototype declaration",
6450 ¤t_function_prototype_locus);
6454 /* Type for passing arg must be consistent with that
6455 declared for the arg. ISO C says we take the unqualified
6456 type for parameters declared with qualified type. */
6457 if (TREE_TYPE (parm) != error_mark_node
6458 && TREE_TYPE (type) != error_mark_node
6459 && !comptypes (TYPE_MAIN_VARIANT (DECL_ARG_TYPE (parm)),
6460 TYPE_MAIN_VARIANT (TREE_VALUE (type))))
6462 if (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
6463 == TYPE_MAIN_VARIANT (TREE_VALUE (type)))
6465 /* Adjust argument to match prototype. E.g. a previous
6466 `int foo(float);' prototype causes
6467 `int foo(x) float x; {...}' to be treated like
6468 `int foo(float x) {...}'. This is particularly
6469 useful for argument types like uid_t. */
6470 DECL_ARG_TYPE (parm) = TREE_TYPE (parm);
6472 if (targetm.calls.promote_prototypes (TREE_TYPE (current_function_decl))
6473 && INTEGRAL_TYPE_P (TREE_TYPE (parm))
6474 && TYPE_PRECISION (TREE_TYPE (parm))
6475 < TYPE_PRECISION (integer_type_node))
6476 DECL_ARG_TYPE (parm) = integer_type_node;
6478 /* ??? Is it possible to get here with a
6479 built-in prototype or will it always have
6480 been diagnosed as conflicting with an
6481 old-style definition and discarded? */
6482 if (current_function_prototype_built_in)
6483 warning (OPT_pedantic, "promoted argument %qD "
6484 "doesn%'t match built-in prototype", parm);
6487 pedwarn (OPT_pedantic, "promoted argument %qD "
6488 "doesn%'t match prototype", parm);
6489 pedwarn (OPT_pedantic, "%Hprototype declaration",
6490 ¤t_function_prototype_locus);
6495 if (current_function_prototype_built_in)
6496 warning (0, "argument %qD doesn%'t match "
6497 "built-in prototype", parm);
6500 error ("argument %qD doesn%'t match prototype", parm);
6501 error ("%Hprototype declaration",
6502 ¤t_function_prototype_locus);
6507 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = 0;
6510 /* Otherwise, create a prototype that would match. */
6514 tree actual = 0, last = 0, type;
6516 for (parm = DECL_ARGUMENTS (fndecl); parm; parm = TREE_CHAIN (parm))
6518 type = tree_cons (NULL_TREE, DECL_ARG_TYPE (parm), NULL_TREE);
6520 TREE_CHAIN (last) = type;
6525 type = tree_cons (NULL_TREE, void_type_node, NULL_TREE);
6527 TREE_CHAIN (last) = type;
6531 /* We are going to assign a new value for the TYPE_ACTUAL_ARG_TYPES
6532 of the type of this function, but we need to avoid having this
6533 affect the types of other similarly-typed functions, so we must
6534 first force the generation of an identical (but separate) type
6535 node for the relevant function type. The new node we create
6536 will be a variant of the main variant of the original function
6539 TREE_TYPE (fndecl) = build_variant_type_copy (TREE_TYPE (fndecl));
6541 TYPE_ACTUAL_ARG_TYPES (TREE_TYPE (fndecl)) = actual;
6545 /* Store parameter declarations passed in ARG_INFO into the current
6546 function declaration. */
6549 store_parm_decls_from (struct c_arg_info *arg_info)
6551 current_function_arg_info = arg_info;
6552 store_parm_decls ();
6555 /* Store the parameter declarations into the current function declaration.
6556 This is called after parsing the parameter declarations, before
6557 digesting the body of the function.
6559 For an old-style definition, construct a prototype out of the old-style
6560 parameter declarations and inject it into the function's type. */
6563 store_parm_decls (void)
6565 tree fndecl = current_function_decl;
6568 /* The argument information block for FNDECL. */
6569 struct c_arg_info *arg_info = current_function_arg_info;
6570 current_function_arg_info = 0;
6572 /* True if this definition is written with a prototype. Note:
6573 despite C99 6.7.5.3p14, we can *not* treat an empty argument
6574 list in a function definition as equivalent to (void) -- an
6575 empty argument list specifies the function has no parameters,
6576 but only (void) sets up a prototype for future calls. */
6577 proto = arg_info->types != 0;
6580 store_parm_decls_newstyle (fndecl, arg_info);
6582 store_parm_decls_oldstyle (fndecl, arg_info);
6584 /* The next call to push_scope will be a function body. */
6586 next_is_function_body = true;
6588 /* Write a record describing this function definition to the prototypes
6589 file (if requested). */
6591 gen_aux_info_record (fndecl, 1, 0, proto);
6593 /* Initialize the RTL code for the function. */
6594 allocate_struct_function (fndecl, false);
6596 /* Begin the statement tree for this function. */
6597 DECL_SAVED_TREE (fndecl) = push_stmt_list ();
6599 /* ??? Insert the contents of the pending sizes list into the function
6600 to be evaluated. The only reason left to have this is
6601 void foo(int n, int array[n++])
6602 because we throw away the array type in favor of a pointer type, and
6603 thus won't naturally see the SAVE_EXPR containing the increment. All
6604 other pending sizes would be handled by gimplify_parameters. */
6607 for (t = nreverse (get_pending_sizes ()); t ; t = TREE_CHAIN (t))
6608 add_stmt (TREE_VALUE (t));
6611 /* Even though we're inside a function body, we still don't want to
6612 call expand_expr to calculate the size of a variable-sized array.
6613 We haven't necessarily assigned RTL to all variables yet, so it's
6614 not safe to try to expand expressions involving them. */
6615 cfun->dont_save_pending_sizes_p = 1;
6618 /* Emit diagnostics that require gimple input for detection. Operate on
6619 FNDECL and all its nested functions. */
6622 c_gimple_diagnostics_recursively (tree fndecl)
6624 struct cgraph_node *cgn;
6625 gimple_seq body = gimple_body (fndecl);
6627 /* Handle attribute((warn_unused_result)). Relies on gimple input. */
6628 c_warn_unused_result (body);
6630 /* Notice when OpenMP structured block constraints are violated. */
6632 diagnose_omp_structured_block_errors (fndecl);
6634 /* Finalize all nested functions now. */
6635 cgn = cgraph_node (fndecl);
6636 for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested)
6637 c_gimple_diagnostics_recursively (cgn->decl);
6640 /* Finish up a function declaration and compile that function
6641 all the way to assembler language output. The free the storage
6642 for the function definition.
6644 This is called after parsing the body of the function definition. */
6647 finish_function (void)
6649 tree fndecl = current_function_decl;
6651 label_context_stack_se = label_context_stack_se->next;
6652 label_context_stack_vm = label_context_stack_vm->next;
6654 if (TREE_CODE (fndecl) == FUNCTION_DECL
6655 && targetm.calls.promote_prototypes (TREE_TYPE (fndecl)))
6657 tree args = DECL_ARGUMENTS (fndecl);
6658 for (; args; args = TREE_CHAIN (args))
6660 tree type = TREE_TYPE (args);
6661 if (INTEGRAL_TYPE_P (type)
6662 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
6663 DECL_ARG_TYPE (args) = integer_type_node;
6667 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node)
6668 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
6670 /* Must mark the RESULT_DECL as being in this function. */
6672 if (DECL_RESULT (fndecl) && DECL_RESULT (fndecl) != error_mark_node)
6673 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
6675 if (MAIN_NAME_P (DECL_NAME (fndecl)) && flag_hosted)
6677 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (fndecl)))
6678 != integer_type_node)
6680 /* If warn_main is 1 (-Wmain) or 2 (-Wall), we have already warned.
6681 If warn_main is -1 (-Wno-main) we don't want to be warned. */
6683 pedwarn (0, "return type of %q+D is not %<int%>", fndecl);
6689 tree stmt = c_finish_return (integer_zero_node);
6690 /* Hack. We don't want the middle-end to warn that this return
6691 is unreachable, so we mark its location as special. Using
6692 UNKNOWN_LOCATION has the problem that it gets clobbered in
6693 annotate_one_with_locus. A cleaner solution might be to
6694 ensure ! should_carry_locus_p (stmt), but that needs a flag.
6696 SET_EXPR_LOCATION (stmt, BUILTINS_LOCATION);
6701 /* Tie off the statement tree for this function. */
6702 DECL_SAVED_TREE (fndecl) = pop_stmt_list (DECL_SAVED_TREE (fndecl));
6704 finish_fname_decls ();
6706 /* Complain if there's just no return statement. */
6707 if (warn_return_type
6708 && TREE_CODE (TREE_TYPE (TREE_TYPE (fndecl))) != VOID_TYPE
6709 && !current_function_returns_value && !current_function_returns_null
6710 /* Don't complain if we are no-return. */
6711 && !current_function_returns_abnormally
6712 /* Don't warn for main(). */
6713 && !MAIN_NAME_P (DECL_NAME (fndecl))
6714 /* Or if they didn't actually specify a return type. */
6715 && !C_FUNCTION_IMPLICIT_INT (fndecl)
6716 /* Normally, with -Wreturn-type, flow will complain, but we might
6717 optimize out static functions. */
6718 && !TREE_PUBLIC (fndecl))
6720 warning (OPT_Wreturn_type,
6721 "no return statement in function returning non-void");
6722 TREE_NO_WARNING (fndecl) = 1;
6725 /* Store the end of the function, so that we get good line number
6726 info for the epilogue. */
6727 cfun->function_end_locus = input_location;
6729 /* Finalize the ELF visibility for the function. */
6730 c_determine_visibility (fndecl);
6732 /* For GNU C extern inline functions disregard inline limits. */
6733 if (DECL_EXTERNAL (fndecl)
6734 && DECL_DECLARED_INLINE_P (fndecl))
6735 DECL_DISREGARD_INLINE_LIMITS (fndecl) = 1;
6737 /* Genericize before inlining. Delay genericizing nested functions
6738 until their parent function is genericized. Since finalizing
6739 requires GENERIC, delay that as well. */
6741 if (DECL_INITIAL (fndecl) && DECL_INITIAL (fndecl) != error_mark_node
6742 && !undef_nested_function)
6744 if (!decl_function_context (fndecl))
6746 c_genericize (fndecl);
6747 c_gimple_diagnostics_recursively (fndecl);
6749 /* ??? Objc emits functions after finalizing the compilation unit.
6750 This should be cleaned up later and this conditional removed. */
6751 if (cgraph_global_info_ready)
6753 cgraph_add_new_function (fndecl, false);
6757 cgraph_finalize_function (fndecl, false);
6761 /* Register this function with cgraph just far enough to get it
6762 added to our parent's nested function list. Handy, since the
6763 C front end doesn't have such a list. */
6764 (void) cgraph_node (fndecl);
6768 if (!decl_function_context (fndecl))
6769 undef_nested_function = false;
6771 /* We're leaving the context of this function, so zap cfun.
6772 It's still in DECL_STRUCT_FUNCTION, and we'll restore it in
6773 tree_rest_of_compilation. */
6775 current_function_decl = NULL;
6778 /* Check the declarations given in a for-loop for satisfying the C99
6779 constraints. If exactly one such decl is found, return it. */
6782 check_for_loop_decls (void)
6784 struct c_binding *b;
6785 tree one_decl = NULL_TREE;
6791 /* If we get here, declarations have been used in a for loop without
6792 the C99 for loop scope. This doesn't make much sense, so don't
6794 error ("%<for%> loop initial declaration used outside C99 mode");
6797 /* C99 subclause 6.8.5 paragraph 3:
6799 [#3] The declaration part of a for statement shall only
6800 declare identifiers for objects having storage class auto or
6803 It isn't clear whether, in this sentence, "identifiers" binds to
6804 "shall only declare" or to "objects" - that is, whether all identifiers
6805 declared must be identifiers for objects, or whether the restriction
6806 only applies to those that are. (A question on this in comp.std.c
6807 in November 2000 received no answer.) We implement the strictest
6808 interpretation, to avoid creating an extension which later causes
6811 for (b = current_scope->bindings; b; b = b->prev)
6814 tree decl = b->decl;
6819 switch (TREE_CODE (decl))
6822 if (TREE_STATIC (decl))
6823 error ("declaration of static variable %q+D in %<for%> loop "
6824 "initial declaration", decl);
6825 else if (DECL_EXTERNAL (decl))
6826 error ("declaration of %<extern%> variable %q+D in %<for%> loop "
6827 "initial declaration", decl);
6831 error ("%<struct %E%> declared in %<for%> loop initial declaration",
6835 error ("%<union %E%> declared in %<for%> loop initial declaration",
6839 error ("%<enum %E%> declared in %<for%> loop initial declaration",
6843 error ("declaration of non-variable %q+D in %<for%> loop "
6844 "initial declaration", decl);
6851 return n_decls == 1 ? one_decl : NULL_TREE;
6854 /* Save and reinitialize the variables
6855 used during compilation of a C function. */
6858 c_push_function_context (void)
6860 struct language_function *p;
6861 p = GGC_NEW (struct language_function);
6864 p->base.x_stmt_tree = c_stmt_tree;
6865 p->x_break_label = c_break_label;
6866 p->x_cont_label = c_cont_label;
6867 p->x_switch_stack = c_switch_stack;
6868 p->arg_info = current_function_arg_info;
6869 p->returns_value = current_function_returns_value;
6870 p->returns_null = current_function_returns_null;
6871 p->returns_abnormally = current_function_returns_abnormally;
6872 p->warn_about_return_type = warn_about_return_type;
6874 push_function_context ();
6877 /* Restore the variables used during compilation of a C function. */
6880 c_pop_function_context (void)
6882 struct language_function *p;
6884 pop_function_context ();
6886 cfun->language = NULL;
6888 if (DECL_STRUCT_FUNCTION (current_function_decl) == 0
6889 && DECL_SAVED_TREE (current_function_decl) == NULL_TREE)
6891 /* Stop pointing to the local nodes about to be freed. */
6892 /* But DECL_INITIAL must remain nonzero so we know this
6893 was an actual function definition. */
6894 DECL_INITIAL (current_function_decl) = error_mark_node;
6895 DECL_ARGUMENTS (current_function_decl) = 0;
6898 c_stmt_tree = p->base.x_stmt_tree;
6899 c_break_label = p->x_break_label;
6900 c_cont_label = p->x_cont_label;
6901 c_switch_stack = p->x_switch_stack;
6902 current_function_arg_info = p->arg_info;
6903 current_function_returns_value = p->returns_value;
6904 current_function_returns_null = p->returns_null;
6905 current_function_returns_abnormally = p->returns_abnormally;
6906 warn_about_return_type = p->warn_about_return_type;
6909 /* Copy the DECL_LANG_SPECIFIC data associated with DECL. */
6912 c_dup_lang_specific_decl (tree decl)
6914 struct lang_decl *ld;
6916 if (!DECL_LANG_SPECIFIC (decl))
6919 ld = GGC_NEW (struct lang_decl);
6920 memcpy (ld, DECL_LANG_SPECIFIC (decl), sizeof (struct lang_decl));
6921 DECL_LANG_SPECIFIC (decl) = ld;
6924 /* The functions below are required for functionality of doing
6925 function at once processing in the C front end. Currently these
6926 functions are not called from anywhere in the C front end, but as
6927 these changes continue, that will change. */
6929 /* Returns the stmt_tree (if any) to which statements are currently
6930 being added. If there is no active statement-tree, NULL is
6934 current_stmt_tree (void)
6936 return &c_stmt_tree;
6939 /* Nonzero if TYPE is an anonymous union or struct type. Always 0 in
6943 anon_aggr_type_p (const_tree ARG_UNUSED (node))
6948 /* Return the global value of T as a symbol. */
6951 identifier_global_value (tree t)
6953 struct c_binding *b;
6955 for (b = I_SYMBOL_BINDING (t); b; b = b->shadowed)
6956 if (B_IN_FILE_SCOPE (b) || B_IN_EXTERNAL_SCOPE (b))
6962 /* Record a builtin type for C. If NAME is non-NULL, it is the name used;
6963 otherwise the name is found in ridpointers from RID_INDEX. */
6966 record_builtin_type (enum rid rid_index, const char *name, tree type)
6970 id = ridpointers[(int) rid_index];
6972 id = get_identifier (name);
6973 decl = build_decl (TYPE_DECL, id, type);
6975 if (debug_hooks->type_decl)
6976 debug_hooks->type_decl (decl, false);
6979 /* Build the void_list_node (void_type_node having been created). */
6981 build_void_list_node (void)
6983 tree t = build_tree_list (NULL_TREE, void_type_node);
6987 /* Return a c_parm structure with the given SPECS, ATTRS and DECLARATOR. */
6990 build_c_parm (struct c_declspecs *specs, tree attrs,
6991 struct c_declarator *declarator)
6993 struct c_parm *ret = XOBNEW (&parser_obstack, struct c_parm);
6996 ret->declarator = declarator;
7000 /* Return a declarator with nested attributes. TARGET is the inner
7001 declarator to which these attributes apply. ATTRS are the
7004 struct c_declarator *
7005 build_attrs_declarator (tree attrs, struct c_declarator *target)
7007 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7008 ret->kind = cdk_attrs;
7009 ret->declarator = target;
7010 ret->u.attrs = attrs;
7014 /* Return a declarator for a function with arguments specified by ARGS
7015 and return type specified by TARGET. */
7017 struct c_declarator *
7018 build_function_declarator (struct c_arg_info *args,
7019 struct c_declarator *target)
7021 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7022 ret->kind = cdk_function;
7023 ret->declarator = target;
7024 ret->u.arg_info = args;
7028 /* Return a declarator for the identifier IDENT (which may be
7029 NULL_TREE for an abstract declarator). */
7031 struct c_declarator *
7032 build_id_declarator (tree ident)
7034 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7036 ret->declarator = 0;
7038 /* Default value - may get reset to a more precise location. */
7039 ret->id_loc = input_location;
7043 /* Return something to represent absolute declarators containing a *.
7044 TARGET is the absolute declarator that the * contains.
7045 TYPE_QUALS_ATTRS is a structure for type qualifiers and attributes
7046 to apply to the pointer type. */
7048 struct c_declarator *
7049 make_pointer_declarator (struct c_declspecs *type_quals_attrs,
7050 struct c_declarator *target)
7054 struct c_declarator *itarget = target;
7055 struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator);
7056 if (type_quals_attrs)
7058 attrs = type_quals_attrs->attrs;
7059 quals = quals_from_declspecs (type_quals_attrs);
7060 if (attrs != NULL_TREE)
7061 itarget = build_attrs_declarator (attrs, target);
7063 ret->kind = cdk_pointer;
7064 ret->declarator = itarget;
7065 ret->u.pointer_quals = quals;
7069 /* Return a pointer to a structure for an empty list of declaration
7072 struct c_declspecs *
7073 build_null_declspecs (void)
7075 struct c_declspecs *ret = XOBNEW (&parser_obstack, struct c_declspecs);
7079 ret->typespec_word = cts_none;
7080 ret->storage_class = csc_none;
7081 ret->declspecs_seen_p = false;
7082 ret->type_seen_p = false;
7083 ret->non_sc_seen_p = false;
7084 ret->typedef_p = false;
7085 ret->tag_defined_p = false;
7086 ret->explicit_signed_p = false;
7087 ret->deprecated_p = false;
7088 ret->default_int_p = false;
7089 ret->long_p = false;
7090 ret->long_long_p = false;
7091 ret->short_p = false;
7092 ret->signed_p = false;
7093 ret->unsigned_p = false;
7094 ret->complex_p = false;
7095 ret->inline_p = false;
7096 ret->thread_p = false;
7097 ret->const_p = false;
7098 ret->volatile_p = false;
7099 ret->restrict_p = false;
7100 ret->saturating_p = false;
7104 /* Add the type qualifier QUAL to the declaration specifiers SPECS,
7107 struct c_declspecs *
7108 declspecs_add_qual (struct c_declspecs *specs, tree qual)
7112 specs->non_sc_seen_p = true;
7113 specs->declspecs_seen_p = true;
7114 gcc_assert (TREE_CODE (qual) == IDENTIFIER_NODE
7115 && C_IS_RESERVED_WORD (qual));
7116 i = C_RID_CODE (qual);
7120 dupe = specs->const_p;
7121 specs->const_p = true;
7124 dupe = specs->volatile_p;
7125 specs->volatile_p = true;
7128 dupe = specs->restrict_p;
7129 specs->restrict_p = true;
7134 if (dupe && !flag_isoc99)
7135 pedwarn (OPT_pedantic, "duplicate %qE", qual);
7139 /* Add the type specifier TYPE to the declaration specifiers SPECS,
7142 struct c_declspecs *
7143 declspecs_add_type (struct c_declspecs *specs, struct c_typespec spec)
7145 tree type = spec.spec;
7146 specs->non_sc_seen_p = true;
7147 specs->declspecs_seen_p = true;
7148 specs->type_seen_p = true;
7149 if (TREE_DEPRECATED (type))
7150 specs->deprecated_p = true;
7152 /* Handle type specifier keywords. */
7153 if (TREE_CODE (type) == IDENTIFIER_NODE
7154 && C_IS_RESERVED_WORD (type)
7155 && C_RID_CODE (type) != RID_CXX_COMPAT_WARN)
7157 enum rid i = C_RID_CODE (type);
7160 error ("two or more data types in declaration specifiers");
7163 if ((int) i <= (int) RID_LAST_MODIFIER)
7165 /* "long", "short", "signed", "unsigned", "_Complex" or "_Sat". */
7170 if (specs->long_long_p)
7172 error ("%<long long long%> is too long for GCC");
7177 if (specs->typespec_word == cts_double)
7179 error ("both %<long long%> and %<double%> in "
7180 "declaration specifiers");
7183 if (pedantic && !flag_isoc99 && !in_system_header)
7184 pedwarn (OPT_Wlong_long, "ISO C90 does not support %<long long%>");
7185 specs->long_long_p = 1;
7189 error ("both %<long%> and %<short%> in "
7190 "declaration specifiers");
7191 else if (specs->typespec_word == cts_void)
7192 error ("both %<long%> and %<void%> in "
7193 "declaration specifiers");
7194 else if (specs->typespec_word == cts_bool)
7195 error ("both %<long%> and %<_Bool%> in "
7196 "declaration specifiers");
7197 else if (specs->typespec_word == cts_char)
7198 error ("both %<long%> and %<char%> in "
7199 "declaration specifiers");
7200 else if (specs->typespec_word == cts_float)
7201 error ("both %<long%> and %<float%> in "
7202 "declaration specifiers");
7203 else if (specs->typespec_word == cts_dfloat32)
7204 error ("both %<long%> and %<_Decimal32%> in "
7205 "declaration specifiers");
7206 else if (specs->typespec_word == cts_dfloat64)
7207 error ("both %<long%> and %<_Decimal64%> in "
7208 "declaration specifiers");
7209 else if (specs->typespec_word == cts_dfloat128)
7210 error ("both %<long%> and %<_Decimal128%> in "
7211 "declaration specifiers");
7213 specs->long_p = true;
7216 dupe = specs->short_p;
7218 error ("both %<long%> and %<short%> in "
7219 "declaration specifiers");
7220 else if (specs->typespec_word == cts_void)
7221 error ("both %<short%> and %<void%> in "
7222 "declaration specifiers");
7223 else if (specs->typespec_word == cts_bool)
7224 error ("both %<short%> and %<_Bool%> in "
7225 "declaration specifiers");
7226 else if (specs->typespec_word == cts_char)
7227 error ("both %<short%> and %<char%> in "
7228 "declaration specifiers");
7229 else if (specs->typespec_word == cts_float)
7230 error ("both %<short%> and %<float%> in "
7231 "declaration specifiers");
7232 else if (specs->typespec_word == cts_double)
7233 error ("both %<short%> and %<double%> in "
7234 "declaration specifiers");
7235 else if (specs->typespec_word == cts_dfloat32)
7236 error ("both %<short%> and %<_Decimal32%> in "
7237 "declaration specifiers");
7238 else if (specs->typespec_word == cts_dfloat64)
7239 error ("both %<short%> and %<_Decimal64%> in "
7240 "declaration specifiers");
7241 else if (specs->typespec_word == cts_dfloat128)
7242 error ("both %<short%> and %<_Decimal128%> in "
7243 "declaration specifiers");
7245 specs->short_p = true;
7248 dupe = specs->signed_p;
7249 if (specs->unsigned_p)
7250 error ("both %<signed%> and %<unsigned%> in "
7251 "declaration specifiers");
7252 else if (specs->typespec_word == cts_void)
7253 error ("both %<signed%> and %<void%> in "
7254 "declaration specifiers");
7255 else if (specs->typespec_word == cts_bool)
7256 error ("both %<signed%> and %<_Bool%> in "
7257 "declaration specifiers");
7258 else if (specs->typespec_word == cts_float)
7259 error ("both %<signed%> and %<float%> in "
7260 "declaration specifiers");
7261 else if (specs->typespec_word == cts_double)
7262 error ("both %<signed%> and %<double%> in "
7263 "declaration specifiers");
7264 else if (specs->typespec_word == cts_dfloat32)
7265 error ("both %<signed%> and %<_Decimal32%> in "
7266 "declaration specifiers");
7267 else if (specs->typespec_word == cts_dfloat64)
7268 error ("both %<signed%> and %<_Decimal64%> in "
7269 "declaration specifiers");
7270 else if (specs->typespec_word == cts_dfloat128)
7271 error ("both %<signed%> and %<_Decimal128%> in "
7272 "declaration specifiers");
7274 specs->signed_p = true;
7277 dupe = specs->unsigned_p;
7278 if (specs->signed_p)
7279 error ("both %<signed%> and %<unsigned%> in "
7280 "declaration specifiers");
7281 else if (specs->typespec_word == cts_void)
7282 error ("both %<unsigned%> and %<void%> in "
7283 "declaration specifiers");
7284 else if (specs->typespec_word == cts_bool)
7285 error ("both %<unsigned%> and %<_Bool%> in "
7286 "declaration specifiers");
7287 else if (specs->typespec_word == cts_float)
7288 error ("both %<unsigned%> and %<float%> in "
7289 "declaration specifiers");
7290 else if (specs->typespec_word == cts_double)
7291 error ("both %<unsigned%> and %<double%> in "
7292 "declaration specifiers");
7293 else if (specs->typespec_word == cts_dfloat32)
7294 error ("both %<unsigned%> and %<_Decimal32%> in "
7295 "declaration specifiers");
7296 else if (specs->typespec_word == cts_dfloat64)
7297 error ("both %<unsigned%> and %<_Decimal64%> in "
7298 "declaration specifiers");
7299 else if (specs->typespec_word == cts_dfloat128)
7300 error ("both %<unsigned%> and %<_Decimal128%> in "
7301 "declaration specifiers");
7303 specs->unsigned_p = true;
7306 dupe = specs->complex_p;
7307 if (!flag_isoc99 && !in_system_header)
7308 pedwarn (OPT_pedantic, "ISO C90 does not support complex types");
7309 if (specs->typespec_word == cts_void)
7310 error ("both %<complex%> and %<void%> in "
7311 "declaration specifiers");
7312 else if (specs->typespec_word == cts_bool)
7313 error ("both %<complex%> and %<_Bool%> in "
7314 "declaration specifiers");
7315 else if (specs->typespec_word == cts_dfloat32)
7316 error ("both %<complex%> and %<_Decimal32%> in "
7317 "declaration specifiers");
7318 else if (specs->typespec_word == cts_dfloat64)
7319 error ("both %<complex%> and %<_Decimal64%> in "
7320 "declaration specifiers");
7321 else if (specs->typespec_word == cts_dfloat128)
7322 error ("both %<complex%> and %<_Decimal128%> in "
7323 "declaration specifiers");
7324 else if (specs->typespec_word == cts_fract)
7325 error ("both %<complex%> and %<_Fract%> in "
7326 "declaration specifiers");
7327 else if (specs->typespec_word == cts_accum)
7328 error ("both %<complex%> and %<_Accum%> in "
7329 "declaration specifiers");
7330 else if (specs->saturating_p)
7331 error ("both %<complex%> and %<_Sat%> in "
7332 "declaration specifiers");
7334 specs->complex_p = true;
7337 dupe = specs->saturating_p;
7338 pedwarn (OPT_pedantic, "ISO C does not support saturating types");
7339 if (specs->typespec_word == cts_void)
7340 error ("both %<_Sat%> and %<void%> in "
7341 "declaration specifiers");
7342 else if (specs->typespec_word == cts_bool)
7343 error ("both %<_Sat%> and %<_Bool%> in "
7344 "declaration specifiers");
7345 else if (specs->typespec_word == cts_char)
7346 error ("both %<_Sat%> and %<char%> in "
7347 "declaration specifiers");
7348 else if (specs->typespec_word == cts_int)
7349 error ("both %<_Sat%> and %<int%> in "
7350 "declaration specifiers");
7351 else if (specs->typespec_word == cts_float)
7352 error ("both %<_Sat%> and %<float%> in "
7353 "declaration specifiers");
7354 else if (specs->typespec_word == cts_double)
7355 error ("both %<_Sat%> and %<double%> in "
7356 "declaration specifiers");
7357 else if (specs->typespec_word == cts_dfloat32)
7358 error ("both %<_Sat%> and %<_Decimal32%> in "
7359 "declaration specifiers");
7360 else if (specs->typespec_word == cts_dfloat64)
7361 error ("both %<_Sat%> and %<_Decimal64%> in "
7362 "declaration specifiers");
7363 else if (specs->typespec_word == cts_dfloat128)
7364 error ("both %<_Sat%> and %<_Decimal128%> in "
7365 "declaration specifiers");
7366 else if (specs->complex_p)
7367 error ("both %<_Sat%> and %<complex%> in "
7368 "declaration specifiers");
7370 specs->saturating_p = true;
7377 error ("duplicate %qE", type);
7383 /* "void", "_Bool", "char", "int", "float", "double", "_Decimal32",
7384 "_Decimal64", "_Decimal128", "_Fract" or "_Accum". */
7385 if (specs->typespec_word != cts_none)
7387 error ("two or more data types in declaration specifiers");
7394 error ("both %<long%> and %<void%> in "
7395 "declaration specifiers");
7396 else if (specs->short_p)
7397 error ("both %<short%> and %<void%> in "
7398 "declaration specifiers");
7399 else if (specs->signed_p)
7400 error ("both %<signed%> and %<void%> in "
7401 "declaration specifiers");
7402 else if (specs->unsigned_p)
7403 error ("both %<unsigned%> and %<void%> in "
7404 "declaration specifiers");
7405 else if (specs->complex_p)
7406 error ("both %<complex%> and %<void%> in "
7407 "declaration specifiers");
7408 else if (specs->saturating_p)
7409 error ("both %<_Sat%> and %<void%> in "
7410 "declaration specifiers");
7412 specs->typespec_word = cts_void;
7416 error ("both %<long%> and %<_Bool%> in "
7417 "declaration specifiers");
7418 else if (specs->short_p)
7419 error ("both %<short%> and %<_Bool%> in "
7420 "declaration specifiers");
7421 else if (specs->signed_p)
7422 error ("both %<signed%> and %<_Bool%> in "
7423 "declaration specifiers");
7424 else if (specs->unsigned_p)
7425 error ("both %<unsigned%> and %<_Bool%> in "
7426 "declaration specifiers");
7427 else if (specs->complex_p)
7428 error ("both %<complex%> and %<_Bool%> in "
7429 "declaration specifiers");
7430 else if (specs->saturating_p)
7431 error ("both %<_Sat%> and %<_Bool%> in "
7432 "declaration specifiers");
7434 specs->typespec_word = cts_bool;
7438 error ("both %<long%> and %<char%> in "
7439 "declaration specifiers");
7440 else if (specs->short_p)
7441 error ("both %<short%> and %<char%> in "
7442 "declaration specifiers");
7443 else if (specs->saturating_p)
7444 error ("both %<_Sat%> and %<char%> in "
7445 "declaration specifiers");
7447 specs->typespec_word = cts_char;
7450 if (specs->saturating_p)
7451 error ("both %<_Sat%> and %<int%> in "
7452 "declaration specifiers");
7454 specs->typespec_word = cts_int;
7458 error ("both %<long%> and %<float%> in "
7459 "declaration specifiers");
7460 else if (specs->short_p)
7461 error ("both %<short%> and %<float%> in "
7462 "declaration specifiers");
7463 else if (specs->signed_p)
7464 error ("both %<signed%> and %<float%> in "
7465 "declaration specifiers");
7466 else if (specs->unsigned_p)
7467 error ("both %<unsigned%> and %<float%> in "
7468 "declaration specifiers");
7469 else if (specs->saturating_p)
7470 error ("both %<_Sat%> and %<float%> in "
7471 "declaration specifiers");
7473 specs->typespec_word = cts_float;
7476 if (specs->long_long_p)
7477 error ("both %<long long%> and %<double%> in "
7478 "declaration specifiers");
7479 else if (specs->short_p)
7480 error ("both %<short%> and %<double%> in "
7481 "declaration specifiers");
7482 else if (specs->signed_p)
7483 error ("both %<signed%> and %<double%> in "
7484 "declaration specifiers");
7485 else if (specs->unsigned_p)
7486 error ("both %<unsigned%> and %<double%> in "
7487 "declaration specifiers");
7488 else if (specs->saturating_p)
7489 error ("both %<_Sat%> and %<double%> in "
7490 "declaration specifiers");
7492 specs->typespec_word = cts_double;
7499 if (i == RID_DFLOAT32)
7501 else if (i == RID_DFLOAT64)
7504 str = "_Decimal128";
7505 if (specs->long_long_p)
7506 error ("both %<long long%> and %<%s%> in "
7507 "declaration specifiers", str);
7509 error ("both %<long%> and %<%s%> in "
7510 "declaration specifiers", str);
7511 else if (specs->short_p)
7512 error ("both %<short%> and %<%s%> in "
7513 "declaration specifiers", str);
7514 else if (specs->signed_p)
7515 error ("both %<signed%> and %<%s%> in "
7516 "declaration specifiers", str);
7517 else if (specs->unsigned_p)
7518 error ("both %<unsigned%> and %<%s%> in "
7519 "declaration specifiers", str);
7520 else if (specs->complex_p)
7521 error ("both %<complex%> and %<%s%> in "
7522 "declaration specifiers", str);
7523 else if (specs->saturating_p)
7524 error ("both %<_Sat%> and %<%s%> in "
7525 "declaration specifiers", str);
7526 else if (i == RID_DFLOAT32)
7527 specs->typespec_word = cts_dfloat32;
7528 else if (i == RID_DFLOAT64)
7529 specs->typespec_word = cts_dfloat64;
7531 specs->typespec_word = cts_dfloat128;
7533 if (!targetm.decimal_float_supported_p ())
7534 error ("decimal floating point not supported for this target");
7535 pedwarn (OPT_pedantic,
7536 "ISO C does not support decimal floating point");
7546 if (specs->complex_p)
7547 error ("both %<complex%> and %<%s%> in "
7548 "declaration specifiers", str);
7549 else if (i == RID_FRACT)
7550 specs->typespec_word = cts_fract;
7552 specs->typespec_word = cts_accum;
7554 if (!targetm.fixed_point_supported_p ())
7555 error ("fixed-point types not supported for this target");
7556 pedwarn (OPT_pedantic,
7557 "ISO C does not support fixed-point types");
7560 /* ObjC reserved word "id", handled below. */
7566 /* Now we have a typedef (a TYPE_DECL node), an identifier (some
7567 form of ObjC type, cases such as "int" and "long" being handled
7568 above), a TYPE (struct, union, enum and typeof specifiers) or an
7569 ERROR_MARK. In none of these cases may there have previously
7570 been any type specifiers. */
7571 if (specs->type || specs->typespec_word != cts_none
7572 || specs->long_p || specs->short_p || specs->signed_p
7573 || specs->unsigned_p || specs->complex_p)
7574 error ("two or more data types in declaration specifiers");
7575 else if (TREE_CODE (type) == TYPE_DECL)
7577 if (TREE_TYPE (type) == error_mark_node)
7578 ; /* Allow the type to default to int to avoid cascading errors. */
7581 specs->type = TREE_TYPE (type);
7582 specs->decl_attr = DECL_ATTRIBUTES (type);
7583 specs->typedef_p = true;
7584 specs->explicit_signed_p = C_TYPEDEF_EXPLICITLY_SIGNED (type);
7587 else if (TREE_CODE (type) == IDENTIFIER_NODE)
7589 tree t = lookup_name (type);
7590 if (!t || TREE_CODE (t) != TYPE_DECL)
7591 error ("%qE fails to be a typedef or built in type", type);
7592 else if (TREE_TYPE (t) == error_mark_node)
7595 specs->type = TREE_TYPE (t);
7597 else if (TREE_CODE (type) != ERROR_MARK)
7599 if (spec.kind == ctsk_tagdef || spec.kind == ctsk_tagfirstref)
7600 specs->tag_defined_p = true;
7601 if (spec.kind == ctsk_typeof)
7602 specs->typedef_p = true;
7609 /* Add the storage class specifier or function specifier SCSPEC to the
7610 declaration specifiers SPECS, returning SPECS. */
7612 struct c_declspecs *
7613 declspecs_add_scspec (struct c_declspecs *specs, tree scspec)
7616 enum c_storage_class n = csc_none;
7618 specs->declspecs_seen_p = true;
7619 gcc_assert (TREE_CODE (scspec) == IDENTIFIER_NODE
7620 && C_IS_RESERVED_WORD (scspec));
7621 i = C_RID_CODE (scspec);
7622 if (specs->non_sc_seen_p)
7623 warning (OPT_Wold_style_declaration,
7624 "%qE is not at beginning of declaration", scspec);
7628 /* C99 permits duplicate inline. Although of doubtful utility,
7629 it seems simplest to permit it in gnu89 mode as well, as
7630 there is also little utility in maintaining this as a
7631 difference between gnu89 and C99 inline. */
7633 specs->inline_p = true;
7636 dupe = specs->thread_p;
7637 if (specs->storage_class == csc_auto)
7638 error ("%<__thread%> used with %<auto%>");
7639 else if (specs->storage_class == csc_register)
7640 error ("%<__thread%> used with %<register%>");
7641 else if (specs->storage_class == csc_typedef)
7642 error ("%<__thread%> used with %<typedef%>");
7644 specs->thread_p = true;
7651 /* Diagnose "__thread extern". */
7652 if (specs->thread_p)
7653 error ("%<__thread%> before %<extern%>");
7660 /* Diagnose "__thread static". */
7661 if (specs->thread_p)
7662 error ("%<__thread%> before %<static%>");
7670 if (n != csc_none && n == specs->storage_class)
7673 error ("duplicate %qE", scspec);
7676 if (specs->storage_class != csc_none && n != specs->storage_class)
7678 error ("multiple storage classes in declaration specifiers");
7682 specs->storage_class = n;
7683 if (n != csc_extern && n != csc_static && specs->thread_p)
7685 error ("%<__thread%> used with %qE", scspec);
7686 specs->thread_p = false;
7693 /* Add the attributes ATTRS to the declaration specifiers SPECS,
7696 struct c_declspecs *
7697 declspecs_add_attrs (struct c_declspecs *specs, tree attrs)
7699 specs->attrs = chainon (attrs, specs->attrs);
7700 specs->declspecs_seen_p = true;
7704 /* Combine "long", "short", "signed", "unsigned" and "_Complex" type
7705 specifiers with any other type specifier to determine the resulting
7706 type. This is where ISO C checks on complex types are made, since
7707 "_Complex long" is a prefix of the valid ISO C type "_Complex long
7710 struct c_declspecs *
7711 finish_declspecs (struct c_declspecs *specs)
7713 /* If a type was specified as a whole, we have no modifiers and are
7715 if (specs->type != NULL_TREE)
7717 gcc_assert (!specs->long_p && !specs->long_long_p && !specs->short_p
7718 && !specs->signed_p && !specs->unsigned_p
7719 && !specs->complex_p);
7723 /* If none of "void", "_Bool", "char", "int", "float" or "double"
7724 has been specified, treat it as "int" unless "_Complex" is
7725 present and there are no other specifiers. If we just have
7726 "_Complex", it is equivalent to "_Complex double", but e.g.
7727 "_Complex short" is equivalent to "_Complex short int". */
7728 if (specs->typespec_word == cts_none)
7730 if (specs->saturating_p)
7732 error ("%<_Sat%> is used without %<_Fract%> or %<_Accum%>");
7733 specs->typespec_word = cts_fract;
7735 else if (specs->long_p || specs->short_p
7736 || specs->signed_p || specs->unsigned_p)
7738 specs->typespec_word = cts_int;
7740 else if (specs->complex_p)
7742 specs->typespec_word = cts_double;
7743 pedwarn (OPT_pedantic,
7744 "ISO C does not support plain %<complex%> meaning "
7745 "%<double complex%>");
7749 specs->typespec_word = cts_int;
7750 specs->default_int_p = true;
7751 /* We don't diagnose this here because grokdeclarator will
7752 give more specific diagnostics according to whether it is
7753 a function definition. */
7757 /* If "signed" was specified, record this to distinguish "int" and
7758 "signed int" in the case of a bit-field with
7759 -funsigned-bitfields. */
7760 specs->explicit_signed_p = specs->signed_p;
7762 /* Now compute the actual type. */
7763 switch (specs->typespec_word)
7766 gcc_assert (!specs->long_p && !specs->short_p
7767 && !specs->signed_p && !specs->unsigned_p
7768 && !specs->complex_p);
7769 specs->type = void_type_node;
7772 gcc_assert (!specs->long_p && !specs->short_p
7773 && !specs->signed_p && !specs->unsigned_p
7774 && !specs->complex_p);
7775 specs->type = boolean_type_node;
7778 gcc_assert (!specs->long_p && !specs->short_p);
7779 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7780 if (specs->signed_p)
7781 specs->type = signed_char_type_node;
7782 else if (specs->unsigned_p)
7783 specs->type = unsigned_char_type_node;
7785 specs->type = char_type_node;
7786 if (specs->complex_p)
7788 pedwarn (OPT_pedantic,
7789 "ISO C does not support complex integer types");
7790 specs->type = build_complex_type (specs->type);
7794 gcc_assert (!(specs->long_p && specs->short_p));
7795 gcc_assert (!(specs->signed_p && specs->unsigned_p));
7796 if (specs->long_long_p)
7797 specs->type = (specs->unsigned_p
7798 ? long_long_unsigned_type_node
7799 : long_long_integer_type_node);
7800 else if (specs->long_p)
7801 specs->type = (specs->unsigned_p
7802 ? long_unsigned_type_node
7803 : long_integer_type_node);
7804 else if (specs->short_p)
7805 specs->type = (specs->unsigned_p
7806 ? short_unsigned_type_node
7807 : short_integer_type_node);
7809 specs->type = (specs->unsigned_p
7810 ? unsigned_type_node
7811 : integer_type_node);
7812 if (specs->complex_p)
7814 pedwarn (OPT_pedantic,
7815 "ISO C does not support complex integer types");
7816 specs->type = build_complex_type (specs->type);
7820 gcc_assert (!specs->long_p && !specs->short_p
7821 && !specs->signed_p && !specs->unsigned_p);
7822 specs->type = (specs->complex_p
7823 ? complex_float_type_node
7827 gcc_assert (!specs->long_long_p && !specs->short_p
7828 && !specs->signed_p && !specs->unsigned_p);
7831 specs->type = (specs->complex_p
7832 ? complex_long_double_type_node
7833 : long_double_type_node);
7837 specs->type = (specs->complex_p
7838 ? complex_double_type_node
7839 : double_type_node);
7845 gcc_assert (!specs->long_p && !specs->long_long_p && !specs->short_p
7846 && !specs->signed_p && !specs->unsigned_p && !specs->complex_p);
7847 if (specs->typespec_word == cts_dfloat32)
7848 specs->type = dfloat32_type_node;
7849 else if (specs->typespec_word == cts_dfloat64)
7850 specs->type = dfloat64_type_node;
7852 specs->type = dfloat128_type_node;
7855 gcc_assert (!specs->complex_p);
7856 if (specs->saturating_p)
7858 if (specs->long_long_p)
7859 specs->type = specs->unsigned_p
7860 ? sat_unsigned_long_long_fract_type_node
7861 : sat_long_long_fract_type_node;
7862 else if (specs->long_p)
7863 specs->type = specs->unsigned_p
7864 ? sat_unsigned_long_fract_type_node
7865 : sat_long_fract_type_node;
7866 else if (specs->short_p)
7867 specs->type = specs->unsigned_p
7868 ? sat_unsigned_short_fract_type_node
7869 : sat_short_fract_type_node;
7871 specs->type = specs->unsigned_p
7872 ? sat_unsigned_fract_type_node
7873 : sat_fract_type_node;
7877 if (specs->long_long_p)
7878 specs->type = specs->unsigned_p
7879 ? unsigned_long_long_fract_type_node
7880 : long_long_fract_type_node;
7881 else if (specs->long_p)
7882 specs->type = specs->unsigned_p
7883 ? unsigned_long_fract_type_node
7884 : long_fract_type_node;
7885 else if (specs->short_p)
7886 specs->type = specs->unsigned_p
7887 ? unsigned_short_fract_type_node
7888 : short_fract_type_node;
7890 specs->type = specs->unsigned_p
7891 ? unsigned_fract_type_node
7896 gcc_assert (!specs->complex_p);
7897 if (specs->saturating_p)
7899 if (specs->long_long_p)
7900 specs->type = specs->unsigned_p
7901 ? sat_unsigned_long_long_accum_type_node
7902 : sat_long_long_accum_type_node;
7903 else if (specs->long_p)
7904 specs->type = specs->unsigned_p
7905 ? sat_unsigned_long_accum_type_node
7906 : sat_long_accum_type_node;
7907 else if (specs->short_p)
7908 specs->type = specs->unsigned_p
7909 ? sat_unsigned_short_accum_type_node
7910 : sat_short_accum_type_node;
7912 specs->type = specs->unsigned_p
7913 ? sat_unsigned_accum_type_node
7914 : sat_accum_type_node;
7918 if (specs->long_long_p)
7919 specs->type = specs->unsigned_p
7920 ? unsigned_long_long_accum_type_node
7921 : long_long_accum_type_node;
7922 else if (specs->long_p)
7923 specs->type = specs->unsigned_p
7924 ? unsigned_long_accum_type_node
7925 : long_accum_type_node;
7926 else if (specs->short_p)
7927 specs->type = specs->unsigned_p
7928 ? unsigned_short_accum_type_node
7929 : short_accum_type_node;
7931 specs->type = specs->unsigned_p
7932 ? unsigned_accum_type_node
7943 /* A subroutine of c_write_global_declarations. Perform final processing
7944 on one file scope's declarations (or the external scope's declarations),
7948 c_write_global_declarations_1 (tree globals)
7953 /* Process the decls in the order they were written. */
7954 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7956 /* Check for used but undefined static functions using the C
7957 standard's definition of "used", and set TREE_NO_WARNING so
7958 that check_global_declarations doesn't repeat the check. */
7959 if (TREE_CODE (decl) == FUNCTION_DECL
7960 && DECL_INITIAL (decl) == 0
7961 && DECL_EXTERNAL (decl)
7962 && !TREE_PUBLIC (decl)
7963 && C_DECL_USED (decl))
7965 pedwarn (0, "%q+F used but never defined", decl);
7966 TREE_NO_WARNING (decl) = 1;
7969 wrapup_global_declaration_1 (decl);
7975 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7976 reconsider |= wrapup_global_declaration_2 (decl);
7980 for (decl = globals; decl; decl = TREE_CHAIN (decl))
7981 check_global_declaration_1 (decl);
7984 /* A subroutine of c_write_global_declarations Emit debug information for each
7985 of the declarations in GLOBALS. */
7988 c_write_global_declarations_2 (tree globals)
7992 for (decl = globals; decl ; decl = TREE_CHAIN (decl))
7993 debug_hooks->global_decl (decl);
7996 /* Preserve the external declarations scope across a garbage collect. */
7997 static GTY(()) tree ext_block;
8000 c_write_global_declarations (void)
8004 /* We don't want to do this if generating a PCH. */
8008 /* Don't waste time on further processing if -fsyntax-only or we've
8009 encountered errors. */
8010 if (flag_syntax_only || errorcount || sorrycount || cpp_errors (parse_in))
8013 /* Close the external scope. */
8014 ext_block = pop_scope ();
8016 gcc_assert (!current_scope);
8020 tree tmp = BLOCK_VARS (ext_block);
8022 FILE * stream = dump_begin (TDI_tu, &flags);
8025 dump_node (tmp, flags & ~TDF_SLIM, stream);
8026 dump_end (TDI_tu, stream);
8030 /* Process all file scopes in this compilation, and the external_scope,
8031 through wrapup_global_declarations and check_global_declarations. */
8032 for (t = all_translation_units; t; t = TREE_CHAIN (t))
8033 c_write_global_declarations_1 (BLOCK_VARS (DECL_INITIAL (t)));
8034 c_write_global_declarations_1 (BLOCK_VARS (ext_block));
8036 /* We're done parsing; proceed to optimize and emit assembly.
8037 FIXME: shouldn't be the front end's responsibility to call this. */
8040 /* After cgraph has had a chance to emit everything that's going to
8041 be emitted, output debug information for globals. */
8042 if (errorcount == 0 && sorrycount == 0)
8044 timevar_push (TV_SYMOUT);
8045 for (t = all_translation_units; t; t = TREE_CHAIN (t))
8046 c_write_global_declarations_2 (BLOCK_VARS (DECL_INITIAL (t)));
8047 c_write_global_declarations_2 (BLOCK_VARS (ext_block));
8048 timevar_pop (TV_SYMOUT);
8054 #include "gt-c-decl.h"