gcc/c-tree.h

   1 /* Definitions for C parsing and type checking.
   2    Copyright (C) 1987, 1993, 1994, 1995, 1997, 1998,
   3    1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 #ifndef GCC_C_TREE_H
  23 #define GCC_C_TREE_H
  24
  25 #include "c-common.h"
  26 #include "diagnostic.h"
  27
  28 /* struct lang_identifier is private to c-decl.c, but langhooks.c needs to
  29    know how big it is.  This is sanity-checked in c-decl.c.  */
  30 #define C_SIZEOF_STRUCT_LANG_IDENTIFIER \
  31   (sizeof (struct c_common_identifier) + 3 * sizeof (void *))
  32
  33 /* Language-specific declaration information.  */
  34
  35 struct lang_decl GTY(())
  36 {
  37   char dummy;
  38 };
  39
  40 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is read-only.  */
  41 #define C_TYPE_FIELDS_READONLY(TYPE) TREE_LANG_FLAG_1 (TYPE)
  42
  43 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is volatile.  */
  44 #define C_TYPE_FIELDS_VOLATILE(TYPE) TREE_LANG_FLAG_2 (TYPE)
  45
  46 /* In a RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE
  47    nonzero if the definition of the type has already started.  */
  48 #define C_TYPE_BEING_DEFINED(TYPE) TYPE_LANG_FLAG_0 (TYPE)
  49
  50 /* In an incomplete RECORD_TYPE or UNION_TYPE, a list of variable
  51    declarations whose type would be completed by completing that type.  */
  52 #define C_TYPE_INCOMPLETE_VARS(TYPE) TYPE_VFIELD (TYPE)
  53
  54 /* In an IDENTIFIER_NODE, nonzero if this identifier is actually a
  55    keyword.  C_RID_CODE (node) is then the RID_* value of the keyword,
  56    and C_RID_YYCODE is the token number wanted by Yacc.  */
  57 #define C_IS_RESERVED_WORD(ID) TREE_LANG_FLAG_0 (ID)
  58
  59 struct lang_type GTY(())
  60 {
  61   /* In a RECORD_TYPE, a sorted array of the fields of the type.  */
  62   struct sorted_fields_type * GTY ((reorder ("resort_sorted_fields"))) s;
  63   /* In an ENUMERAL_TYPE, the min and max values.  */
  64   tree enum_min;
  65   tree enum_max;
  66   /* In a RECORD_TYPE, information specific to Objective-C, such
  67      as a list of adopted protocols or a pointer to a corresponding
  68      @interface.  See objc/objc-act.h for details.  */
  69   tree objc_info;
  70 };
  71
  72 /* Record whether a type or decl was written with nonconstant size.
  73    Note that TYPE_SIZE may have simplified to a constant.  */
  74 #define C_TYPE_VARIABLE_SIZE(TYPE) TYPE_LANG_FLAG_1 (TYPE)
  75 #define C_DECL_VARIABLE_SIZE(TYPE) DECL_LANG_FLAG_0 (TYPE)
  76
  77 /* Record whether a typedef for type `int' was actually `signed int'.  */
  78 #define C_TYPEDEF_EXPLICITLY_SIGNED(EXP) DECL_LANG_FLAG_1 (EXP)
  79
  80 /* For a FUNCTION_DECL, nonzero if it was defined without an explicit
  81    return type.  */
  82 #define C_FUNCTION_IMPLICIT_INT(EXP) DECL_LANG_FLAG_1 (EXP)
  83
  84 /* For a FUNCTION_DECL, nonzero if it was an implicit declaration.  */
  85 #define C_DECL_IMPLICIT(EXP) DECL_LANG_FLAG_2 (EXP)
  86
  87 /* For FUNCTION_DECLs, evaluates true if the decl is built-in but has
  88    been declared.  */
  89 #define C_DECL_DECLARED_BUILTIN(EXP) DECL_LANG_FLAG_3 (EXP)
  90
  91 /* Record whether a decl was declared register.  This is strictly a
  92    front-end flag, whereas DECL_REGISTER is used for code generation;
  93    they may differ for structures with volatile fields.  */
  94 #define C_DECL_REGISTER(EXP) DECL_LANG_FLAG_4 (EXP)
  95
  96 /* Record whether a decl was used in an expression anywhere except an
  97    unevaluated operand of sizeof / typeof / alignof.  This is only
  98    used for functions declared static but not defined, though outside
  99    sizeof and typeof it is set for other function decls as well.  */
 100 #define C_DECL_USED(EXP) DECL_LANG_FLAG_5 (EXP)
 101
 102 /* Record whether a label was defined in a statement expression which
 103    has finished and so can no longer be jumped to.  */
 104 #define C_DECL_UNJUMPABLE_STMT_EXPR(EXP)        \
 105   DECL_LANG_FLAG_6 (LABEL_DECL_CHECK (EXP))
 106
 107 /* Record whether a label was the subject of a goto from outside the
 108    current level of statement expression nesting and so cannot be
 109    defined right now.  */
 110 #define C_DECL_UNDEFINABLE_STMT_EXPR(EXP)       \
 111   DECL_LANG_FLAG_7 (LABEL_DECL_CHECK (EXP))
 112
 113 /* Nonzero for a decl which either doesn't exist or isn't a prototype.
 114    N.B. Could be simplified if all built-in decls had complete prototypes
 115    (but this is presently difficult because some of them need FILE*).  */
 116 #define C_DECL_ISNT_PROTOTYPE(EXP)                      \
 117        (EXP == 0                                        \
 118         || (TYPE_ARG_TYPES (TREE_TYPE (EXP)) == 0       \
 119             && !DECL_BUILT_IN (EXP)))
 120
 121 /* For FUNCTION_TYPE, a hidden list of types of arguments.  The same as
 122    TYPE_ARG_TYPES for functions with prototypes, but created for functions
 123    without prototypes.  */
 124 #define TYPE_ACTUAL_ARG_TYPES(NODE) TYPE_LANG_SLOT_1 (NODE)
 125
 126 /* Record parser information about an expression that is irrelevant
 127    for code generation alongside a tree representing its value.  */
 128 struct c_expr
 129 {
 130   /* The value of the expression.  */
 131   tree value;
 132   /* Record the original binary operator of an expression, which may
 133      have been changed by fold, STRING_CST for unparenthesized string
 134      constants, or ERROR_MARK for other expressions (including
 135      parenthesized expressions).  */
 136   enum tree_code original_code;
 137 };
 138
 139 /* A kind of type specifier.  Note that this information is currently
 140    only used to distinguish tag definitions, tag references and typeof
 141    uses.  */
 142 enum c_typespec_kind {
 143   /* A reserved keyword type specifier.  */
 144   ctsk_resword,
 145   /* A reference to a tag, previously declared, such as "struct foo".
 146      This includes where the previous declaration was as a different
 147      kind of tag, in which case this is only valid if shadowing that
 148      tag in an inner scope.  */
 149   ctsk_tagref,
 150   /* A reference to a tag, not previously declared in a visible
 151      scope.  */
 152   ctsk_tagfirstref,
 153   /* A definition of a tag such as "struct foo { int a; }".  */
 154   ctsk_tagdef,
 155   /* A typedef name.  */
 156   ctsk_typedef,
 157   /* An ObjC-specific kind of type specifier.  */
 158   ctsk_objc,
 159   /* A typeof specifier.  */
 160   ctsk_typeof
 161 };
 162
 163 /* A type specifier: this structure is created in the parser and
 164    passed to declspecs_add_type only.  */
 165 struct c_typespec {
 166   /* What kind of type specifier this is.  */
 167   enum c_typespec_kind kind;
 168   /* The specifier itself.  */
 169   tree spec;
 170 };
 171
 172 /* A storage class specifier.  */
 173 enum c_storage_class {
 174   csc_none,
 175   csc_auto,
 176   csc_extern,
 177   csc_register,
 178   csc_static,
 179   csc_typedef
 180 };
 181
 182 /* A type specifier keyword "void", "_Bool", "char", "int", "float",
 183    "double", or none of these.  */
 184 enum c_typespec_keyword {
 185   cts_none,
 186   cts_void,
 187   cts_bool,
 188   cts_char,
 189   cts_int,
 190   cts_float,
 191   cts_double
 192 };
 193
 194 /* A sequence of declaration specifiers in C.  */
 195 struct c_declspecs {
 196   /* The type specified, if a single type specifier such as a struct,
 197      union or enum specifier, typedef name or typeof specifies the
 198      whole type, or NULL_TREE if none or a keyword such as "void" or
 199      "char" is used.  Does not include qualifiers.  */
 200   tree type;
 201   /* The attributes from a typedef decl.  */
 202   tree decl_attr;
 203   /* When parsing, the attributes.  Outside the parser, this will be
 204      NULL; attributes (possibly from multiple lists) will be passed
 205      separately.  */
 206   tree attrs;
 207   /* Any type specifier keyword used such as "int", not reflecting
 208      modifiers such as "short", or cts_none if none.  */
 209   enum c_typespec_keyword typespec_word;
 210   /* The storage class specifier, or csc_none if none.  */
 211   enum c_storage_class storage_class;
 212   /* Whether any declaration specifiers have been seen at all.  */
 213   BOOL_BITFIELD declspecs_seen_p : 1;
 214   /* Whether a type specifier has been seen.  */
 215   BOOL_BITFIELD type_seen_p : 1;
 216   /* Whether something other than a storage class specifier or
 217      attribute has been seen.  This is used to warn for the
 218      obsolescent usage of storage class specifiers other than at the
 219      start of the list.  (Doing this properly would require function
 220      specifiers to be handled separately from storage class
 221      specifiers.)  */
 222   BOOL_BITFIELD non_sc_seen_p : 1;
 223   /* Whether the type is specified by a typedef or typeof name.  */
 224   BOOL_BITFIELD typedef_p : 1;
 225   /* Whether a struct, union or enum type either had its content
 226      defined by a type specifier in the list or was the first visible
 227      declaration of its tag.  */
 228   BOOL_BITFIELD tag_defined_p : 1;
 229   /* Whether the type is explicitly "signed" or specified by a typedef
 230      whose type is explicitly "signed".  */
 231   BOOL_BITFIELD explicit_signed_p : 1;
 232   /* Whether the specifiers include a deprecated typedef.  */
 233   BOOL_BITFIELD deprecated_p : 1;
 234   /* Whether the type defaulted to "int" because there were no type
 235      specifiers.  */
 236   BOOL_BITFIELD default_int_p;
 237   /* Whether "long" was specified.  */
 238   BOOL_BITFIELD long_p : 1;
 239   /* Whether "long" was specified more than once.  */
 240   BOOL_BITFIELD long_long_p : 1;
 241   /* Whether "short" was specified.  */
 242   BOOL_BITFIELD short_p : 1;
 243   /* Whether "signed" was specified.  */
 244   BOOL_BITFIELD signed_p : 1;
 245   /* Whether "unsigned" was specified.  */
 246   BOOL_BITFIELD unsigned_p : 1;
 247   /* Whether "complex" was specified.  */
 248   BOOL_BITFIELD complex_p : 1;
 249   /* Whether "inline" was specified.  */
 250   BOOL_BITFIELD inline_p : 1;
 251   /* Whether "__thread" was specified.  */
 252   BOOL_BITFIELD thread_p : 1;
 253   /* Whether "const" was specified.  */
 254   BOOL_BITFIELD const_p : 1;
 255   /* Whether "volatile" was specified.  */
 256   BOOL_BITFIELD volatile_p : 1;
 257   /* Whether "restrict" was specified.  */
 258   BOOL_BITFIELD restrict_p : 1;
 259 };
 260
 261 /* The various kinds of declarators in C.  */
 262 enum c_declarator_kind {
 263   /* An identifier.  */
 264   cdk_id,
 265   /* A function.  */
 266   cdk_function,
 267   /* An array.  */
 268   cdk_array,
 269   /* A pointer.  */
 270   cdk_pointer,
 271   /* Parenthesized declarator with nested attributes.  */
 272   cdk_attrs
 273 };
 274
 275 /* Information about the parameters in a function declarator.  */
 276 struct c_arg_info {
 277   /* A list of parameter decls.  */
 278   tree parms;
 279   /* A list of structure, union and enum tags defined.  */
 280   tree tags;
 281   /* A list of argument types to go in the FUNCTION_TYPE.  */
 282   tree types;
 283   /* A list of non-parameter decls (notably enumeration constants)
 284      defined with the parameters.  */
 285   tree others;
 286 };
 287
 288 /* A declarator.  */
 289 struct c_declarator {
 290   /* The kind of declarator.  */
 291   enum c_declarator_kind kind;
 292   /* Except for cdk_id, the contained declarator.  For cdk_id, NULL.  */
 293   struct c_declarator *declarator;
 294   location_t id_loc; /* Currently only set for cdk_id. */
 295   union {
 296     /* For identifiers, an IDENTIFIER_NODE or NULL_TREE if an abstract
 297        declarator.  */
 298     tree id;
 299     /* For functions.  */
 300     struct c_arg_info *arg_info;
 301     /* For arrays.  */
 302     struct {
 303       /* The array dimension, or NULL for [] and [*].  */
 304       tree dimen;
 305       /* The qualifiers inside [].  */
 306       int quals;
 307       /* The attributes (currently ignored) inside [].  */
 308       tree attrs;
 309       /* Whether [static] was used.  */
 310       BOOL_BITFIELD static_p : 1;
 311       /* Whether [*] was used.  */
 312       BOOL_BITFIELD vla_unspec_p : 1;
 313     } array;
 314     /* For pointers, the qualifiers on the pointer type.  */
 315     int pointer_quals;
 316     /* For attributes.  */
 317     tree attrs;
 318   } u;
 319 };
 320
 321 /* A type name.  */
 322 struct c_type_name {
 323   /* The declaration specifiers.  */
 324   struct c_declspecs *specs;
 325   /* The declarator.  */
 326   struct c_declarator *declarator;
 327 };
 328
 329 /* A parameter.  */
 330 struct c_parm {
 331   /* The declaration specifiers, minus any prefix attributes.  */
 332   struct c_declspecs *specs;
 333   /* The attributes.  */
 334   tree attrs;
 335   /* The declarator.  */
 336   struct c_declarator *declarator;
 337 };
 338
 339 /* Save and restore the variables in this file and elsewhere
 340    that keep track of the progress of compilation of the current function.
 341    Used for nested functions.  */
 342
 343 struct language_function GTY(())
 344 {
 345   struct c_language_function base;
 346   tree x_break_label;
 347   tree x_cont_label;
 348   struct c_switch * GTY((skip)) x_switch_stack;
 349   struct c_arg_info * GTY((skip)) arg_info;
 350   int returns_value;
 351   int returns_null;
 352   int returns_abnormally;
 353   int warn_about_return_type;
 354   int extern_inline;
 355 };
 356
 357 /* Save lists of labels used or defined in particular statement
 358    expression contexts.  Allocated on the parser obstack.  */
 359
 360 struct c_label_list
 361 {
 362   /* The label at the head of the list.  */
 363   tree label;
 364   /* The rest of the list.  */
 365   struct c_label_list *next;
 366 };
 367
 368 struct c_label_context
 369 {
 370   /* The labels defined at this level of nesting.  */
 371   struct c_label_list *labels_def;
 372   /* The labels used at this level of nesting.  */
 373   struct c_label_list *labels_used;
 374   /* The next outermost context.  */
 375   struct c_label_context *next;
 376 };
 377
 378 \f
 379 /* in c-parser.c */
 380 extern void c_parse_init (void);
 381
 382 /* in c-aux-info.c */
 383 extern void gen_aux_info_record (tree, int, int, int);
 384
 385 /* in c-decl.c */
 386 extern struct obstack parser_obstack;
 387 extern tree c_break_label;
 388 extern tree c_cont_label;
 389
 390 extern int global_bindings_p (void);
 391 extern void push_scope (void);
 392 extern tree pop_scope (void);
 393 extern void insert_block (tree);
 394 extern tree pushdecl (tree);
 395 extern void c_expand_body (tree);
 396
 397 extern void c_init_decl_processing (void);
 398 extern void c_dup_lang_specific_decl (tree);
 399 extern void c_print_identifier (FILE *, tree, int);
 400 extern int quals_from_declspecs (const struct c_declspecs *);
 401 extern struct c_declarator *build_array_declarator (tree, struct c_declspecs *,
 402                                                     bool, bool);
 403 extern tree build_enumerator (tree, tree);
 404 extern void check_for_loop_decls (void);
 405 extern void mark_forward_parm_decls (void);
 406 extern void declare_parm_level (void);
 407 extern void undeclared_variable (tree, location_t);
 408 extern tree declare_label (tree);
 409 extern tree define_label (location_t, tree);
 410 extern void finish_decl (tree, tree, tree);
 411 extern tree finish_enum (tree, tree, tree);
 412 extern void finish_function (void);
 413 extern tree finish_struct (tree, tree, tree);
 414 extern struct c_arg_info *get_parm_info (bool);
 415 extern tree grokfield (struct c_declarator *, struct c_declspecs *, tree);
 416 extern tree groktypename (struct c_type_name *);
 417 extern tree grokparm (const struct c_parm *);
 418 extern tree implicitly_declare (tree);
 419 extern void keep_next_level (void);
 420 extern tree lookup_name (tree);
 421 extern void pending_xref_error (void);
 422 extern void c_push_function_context (struct function *);
 423 extern void c_pop_function_context (struct function *);
 424 extern void push_parm_decl (const struct c_parm *);
 425 extern tree pushdecl_top_level (tree);
 426 extern struct c_declarator *set_array_declarator_inner (struct c_declarator *,
 427                                                         struct c_declarator *,
 428                                                         bool);
 429 extern tree builtin_function (const char *, tree, int, enum built_in_class,
 430                               const char *, tree);
 431 extern void shadow_tag (const struct c_declspecs *);
 432 extern void shadow_tag_warned (const struct c_declspecs *, int);
 433 extern tree start_enum (tree);
 434 extern int  start_function (struct c_declspecs *, struct c_declarator *, tree);
 435 extern tree start_decl (struct c_declarator *, struct c_declspecs *, bool,
 436                         tree);
 437 extern tree start_struct (enum tree_code, tree);
 438 extern void store_parm_decls (void);
 439 extern void store_parm_decls_from (struct c_arg_info *);
 440 extern tree xref_tag (enum tree_code, tree);
 441 extern struct c_typespec parser_xref_tag (enum tree_code, tree);
 442 extern int c_expand_decl (tree);
 443 extern struct c_parm *build_c_parm (struct c_declspecs *, tree,
 444                                     struct c_declarator *);
 445 extern struct c_declarator *build_attrs_declarator (tree,
 446                                                     struct c_declarator *);
 447 extern struct c_declarator *build_function_declarator (struct c_arg_info *,
 448                                                        struct c_declarator *);
 449 extern struct c_declarator *build_id_declarator (tree);
 450 extern struct c_declarator *make_pointer_declarator (struct c_declspecs *,
 451                                                      struct c_declarator *);
 452 extern struct c_declspecs *build_null_declspecs (void);
 453 extern struct c_declspecs *declspecs_add_qual (struct c_declspecs *, tree);
 454 extern struct c_declspecs *declspecs_add_type (struct c_declspecs *,
 455                                                struct c_typespec);
 456 extern struct c_declspecs *declspecs_add_scspec (struct c_declspecs *, tree);
 457 extern struct c_declspecs *declspecs_add_attrs (struct c_declspecs *, tree);
 458 extern struct c_declspecs *finish_declspecs (struct c_declspecs *);
 459
 460 /* in c-objc-common.c */
 461 extern int c_disregard_inline_limits (tree);
 462 extern int c_cannot_inline_tree_fn (tree *);
 463 extern bool c_objc_common_init (void);
 464 extern bool c_missing_noreturn_ok_p (tree);
 465 extern tree c_objc_common_truthvalue_conversion (tree expr);
 466 extern bool c_warn_unused_global_decl (tree);
 467 extern void c_initialize_diagnostics (diagnostic_context *);
 468
 469 #define c_build_type_variant(TYPE, CONST_P, VOLATILE_P)           \
 470   c_build_qualified_type ((TYPE),                                 \
 471                           ((CONST_P) ? TYPE_QUAL_CONST : 0) |     \
 472                           ((VOLATILE_P) ? TYPE_QUAL_VOLATILE : 0))
 473
 474 /* in c-typeck.c */
 475 extern int in_alignof;
 476 extern int in_sizeof;
 477 extern int in_typeof;
 478
 479 extern struct c_switch *c_switch_stack;
 480 extern struct c_label_context *label_context_stack;
 481
 482 extern tree require_complete_type (tree);
 483 extern int same_translation_unit_p (tree, tree);
 484 extern int comptypes (tree, tree);
 485 extern bool c_mark_addressable (tree);
 486 extern void c_incomplete_type_error (tree, tree);
 487 extern tree c_type_promotes_to (tree);
 488 extern tree default_conversion (tree);
 489 extern tree composite_type (tree, tree);
 490 extern tree build_component_ref (tree, tree);
 491 extern tree build_indirect_ref (tree, const char *);
 492 extern tree build_array_ref (tree, tree);
 493 extern tree build_external_ref (tree, int, location_t);
 494 extern void pop_maybe_used (bool);
 495 extern struct c_expr c_expr_sizeof_expr (struct c_expr);
 496 extern struct c_expr c_expr_sizeof_type (struct c_type_name *);
 497 extern struct c_expr parser_build_binary_op (enum tree_code, struct c_expr,
 498                                              struct c_expr);
 499 extern tree build_conditional_expr (tree, tree, tree);
 500 extern tree build_compound_expr (tree, tree);
 501 extern tree c_cast_expr (struct c_type_name *, tree);
 502 extern tree build_c_cast (tree, tree);
 503 extern tree build_modify_expr (tree, enum tree_code, tree);
 504 extern void store_init_value (tree, tree);
 505 extern void error_init (const char *);
 506 extern void pedwarn_init (const char *);
 507 extern void maybe_warn_string_init (tree, struct c_expr);
 508 extern void start_init (tree, tree, int);
 509 extern void finish_init (void);
 510 extern void really_start_incremental_init (tree);
 511 extern void push_init_level (int);
 512 extern struct c_expr pop_init_level (int);
 513 extern void set_init_index (tree, tree);
 514 extern void set_init_label (tree);
 515 extern void process_init_element (struct c_expr);
 516 extern tree build_compound_literal (tree, tree);
 517 extern tree c_start_case (tree);
 518 extern void c_finish_case (tree);
 519 extern tree build_asm_expr (tree, tree, tree, tree, bool);
 520 extern tree build_asm_stmt (tree, tree);
 521 extern tree c_convert_parm_for_inlining (tree, tree, tree, int);
 522 extern int c_types_compatible_p (tree, tree);
 523 extern tree c_begin_compound_stmt (bool);
 524 extern tree c_end_compound_stmt (tree, bool);
 525 extern void c_finish_if_stmt (location_t, tree, tree, tree, bool);
 526 extern void c_finish_loop (location_t, tree, tree, tree, tree, tree, bool);
 527 extern tree c_begin_stmt_expr (void);
 528 extern tree c_finish_stmt_expr (tree);
 529 extern tree c_process_expr_stmt (tree);
 530 extern tree c_finish_expr_stmt (tree);
 531 extern tree c_finish_return (tree);
 532 extern tree c_finish_bc_stmt (tree *, bool);
 533 extern tree c_finish_goto_label (tree);
 534 extern tree c_finish_goto_ptr (tree);
 535
 536 /* Set to 0 at beginning of a function definition, set to 1 if
 537    a return statement that specifies a return value is seen.  */
 538
 539 extern int current_function_returns_value;
 540
 541 /* Set to 0 at beginning of a function definition, set to 1 if
 542    a return statement with no argument is seen.  */
 543
 544 extern int current_function_returns_null;
 545
 546 /* Set to 0 at beginning of a function definition, set to 1 if
 547    a call to a noreturn function is seen.  */
 548
 549 extern int current_function_returns_abnormally;
 550
 551 /* Nonzero means we are reading code that came from a system header file.  */
 552
 553 extern int system_header_p;
 554
 555 /* True means global_bindings_p should return false even if the scope stack
 556    says we are in file scope.  */
 557
 558 extern bool c_override_global_bindings_to_false;
 559
 560 /* True means we've initialized exception handling.  */
 561 extern bool c_eh_initialized_p;
 562
 563 /* In c-decl.c */
 564 extern void c_finish_incomplete_decl (tree);
 565 extern void c_write_global_declarations (void);
 566
 567 /* In order for the format checking to accept the C frontend
 568    diagnostic framework extensions, you must include this file before
 569    toplev.h, not after.  */
 570 #define GCC_DIAG_STYLE __gcc_cdiag__
 571 #if GCC_VERSION >= 3005
 572 #define ATTRIBUTE_GCC_CDIAG(m, n) __attribute__ ((__format__ (GCC_DIAG_STYLE, m ,n))) ATTRIBUTE_NONNULL(m)
 573 #else
 574 #define ATTRIBUTE_GCC_CDIAG(m, n) ATTRIBUTE_NONNULL(m)
 575 #endif
 576
 577 extern void pedwarn_c90 (const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2);
 578 extern void pedwarn_c99 (const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2);
 579
 580 #endif /* ! GCC_C_TREE_H */