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 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 /* For gc purposes, return the most likely link for the longest chain.  */
  34 #define C_LANG_TREE_NODE_CHAIN_NEXT(T)                          \
  35   ((union lang_tree_node *)                                     \
  36    (TREE_CODE (T) == INTEGER_TYPE ? TYPE_NEXT_VARIANT (T)       \
  37     : TREE_CODE (T) == COMPOUND_EXPR ? TREE_OPERAND (T, 1)      \
  38     : TREE_CHAIN (T)))
  39
  40 /* Language-specific declaration information.  */
  41
  42 struct lang_decl GTY(())
  43 {
  44   /* The return types and parameter types may have variable size.
  45      This is a list of any SAVE_EXPRs that need to be evaluated to
  46      compute those sizes.  */
  47   tree pending_sizes;
  48 };
  49
  50 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is read-only.  */
  51 #define C_TYPE_FIELDS_READONLY(TYPE) TREE_LANG_FLAG_1 (TYPE)
  52
  53 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is volatile.  */
  54 #define C_TYPE_FIELDS_VOLATILE(TYPE) TREE_LANG_FLAG_2 (TYPE)
  55
  56 /* In a RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE
  57    nonzero if the definition of the type has already started.  */
  58 #define C_TYPE_BEING_DEFINED(TYPE) TYPE_LANG_FLAG_0 (TYPE)
  59
  60 /* In an incomplete RECORD_TYPE or UNION_TYPE, a list of variable
  61    declarations whose type would be completed by completing that type.  */
  62 #define C_TYPE_INCOMPLETE_VARS(TYPE) TYPE_VFIELD (TYPE)
  63
  64 /* In an IDENTIFIER_NODE, nonzero if this identifier is actually a
  65    keyword.  C_RID_CODE (node) is then the RID_* value of the keyword,
  66    and C_RID_YYCODE is the token number wanted by Yacc.  */
  67 #define C_IS_RESERVED_WORD(ID) TREE_LANG_FLAG_0 (ID)
  68
  69 struct lang_type GTY(())
  70 {
  71   /* In a RECORD_TYPE, a sorted array of the fields of the type.  */
  72   struct sorted_fields_type * GTY ((reorder ("resort_sorted_fields"))) s;
  73   /* In an ENUMERAL_TYPE, the min and max values.  */
  74   tree enum_min;
  75   tree enum_max;
  76 };
  77
  78 /* Record whether a type or decl was written with nonconstant size.
  79    Note that TYPE_SIZE may have simplified to a constant.  */
  80 #define C_TYPE_VARIABLE_SIZE(TYPE) TYPE_LANG_FLAG_1 (TYPE)
  81 #define C_DECL_VARIABLE_SIZE(TYPE) DECL_LANG_FLAG_0 (TYPE)
  82
  83 /* Record whether a typedef for type `int' was actually `signed int'.  */
  84 #define C_TYPEDEF_EXPLICITLY_SIGNED(EXP) DECL_LANG_FLAG_1 (EXP)
  85
  86 /* For a FUNCTION_DECL, nonzero if it was defined without an explicit
  87    return type.  */
  88 #define C_FUNCTION_IMPLICIT_INT(EXP) DECL_LANG_FLAG_1 (EXP)
  89
  90 /* For a FUNCTION_DECL, nonzero if it was an implicit declaration.  */
  91 #define C_DECL_IMPLICIT(EXP) DECL_LANG_FLAG_2 (EXP)
  92
  93 /* For FUNCTION_DECLs, evaluates true if the decl is built-in but has
  94    been declared.  */
  95 #define C_DECL_DECLARED_BUILTIN(EXP) DECL_LANG_FLAG_3 (EXP)
  96
  97 /* Record whether a decl was declared register.  This is strictly a
  98    front-end flag, whereas DECL_REGISTER is used for code generation;
  99    they may differ for structures with volatile fields.  */
 100 #define C_DECL_REGISTER(EXP) DECL_LANG_FLAG_4 (EXP)
 101
 102 /* Record whether a decl was used in an expression anywhere except an
 103    unevaluated operand of sizeof / typeof / alignof.  This is only
 104    used for functions declared static but not defined, though outside
 105    sizeof and typeof it is set for other function decls as well.  */
 106 #define C_DECL_USED(EXP) DECL_LANG_FLAG_5 (EXP)
 107
 108 /* Nonzero for a decl which either doesn't exist or isn't a prototype.
 109    N.B. Could be simplified if all built-in decls had complete prototypes
 110    (but this is presently difficult because some of them need FILE*).  */
 111 #define C_DECL_ISNT_PROTOTYPE(EXP)                      \
 112        (EXP == 0                                        \
 113         || (TYPE_ARG_TYPES (TREE_TYPE (EXP)) == 0       \
 114             && !DECL_BUILT_IN (EXP)))
 115
 116 /* For FUNCTION_TYPE, a hidden list of types of arguments.  The same as
 117    TYPE_ARG_TYPES for functions with prototypes, but created for functions
 118    without prototypes.  */
 119 #define TYPE_ACTUAL_ARG_TYPES(NODE) TYPE_LANG_SLOT_1 (NODE)
 120
 121 /* Record parser information about an expression that is irrelevant
 122    for code generation alongside a tree representing its value.  */
 123 struct c_expr
 124 {
 125   /* The value of the expression.  */
 126   tree value;
 127   /* Record the original binary operator of an expression, which may
 128      have been changed by fold, STRING_CST for unparenthesised string
 129      constants, or ERROR_MARK for other expressions (including
 130      parenthesized expressions).  */
 131   enum tree_code original_code;
 132 };
 133
 134 /* A storage class specifier.  */
 135 enum c_storage_class {
 136   csc_none,
 137   csc_auto,
 138   csc_extern,
 139   csc_register,
 140   csc_static,
 141   csc_typedef
 142 };
 143
 144 /* A sequence of declaration specifiers in C.  */
 145 struct c_declspecs {
 146   /* The type specified, not reflecting modifiers such as "short" and
 147      "unsigned", or NULL_TREE if none.  */
 148   tree type;
 149   /* The attributes from a typedef decl.  */
 150   tree decl_attr;
 151   /* When parsing, the attributes.  Outside the parser, this will be
 152      NULL; attributes (possibly from multiple lists) will be passed
 153      separately.  */
 154   tree attrs;
 155   /* The modifier bits present.  */
 156   int specbits;
 157   /* The storage class specifier, or csc_none if none.  */
 158   enum c_storage_class storage_class;
 159   /* Whether something other than a storage class specifier or
 160      attribute has been seen.  This is used to warn for the
 161      obsolescent usage of storage class specifiers other than at the
 162      start of the list.  (Doing this properly would require function
 163      specifiers to be handled separately from storage class
 164      specifiers.)  */
 165   BOOL_BITFIELD non_sc_seen_p : 1;
 166   /* Whether the type is specified by a typedef.  */
 167   BOOL_BITFIELD typedef_p : 1;
 168   /* Whether the type is specified by a typedef whose type is
 169      explicitly "signed".  */
 170   BOOL_BITFIELD typedef_signed_p : 1;
 171   /* Whether the specifiers include a deprecated typedef.  */
 172   BOOL_BITFIELD deprecated_p : 1;
 173   /* Whether "int" was explicitly specified.  */
 174   BOOL_BITFIELD explicit_int_p : 1;
 175   /* Whether "char" was explicitly specified.  */
 176   BOOL_BITFIELD explicit_char_p : 1;
 177   /* Whether "long" was specified more than once.  */
 178   BOOL_BITFIELD long_long_p : 1;
 179   /* Whether "inline" was specified.  */
 180   BOOL_BITFIELD inline_p : 1;
 181   /* Whether "__thread" was specified.  */
 182   BOOL_BITFIELD thread_p : 1;
 183   /* Whether "const" was specified.  */
 184   BOOL_BITFIELD const_p : 1;
 185   /* Whether "volatile" was specified.  */
 186   BOOL_BITFIELD volatile_p : 1;
 187   /* Whether "restrict" was specified.  */
 188   BOOL_BITFIELD restrict_p : 1;
 189 };
 190
 191 /* The various kinds of declarators in C.  */
 192 enum c_declarator_kind {
 193   /* An identifier.  */
 194   cdk_id,
 195   /* A function.  */
 196   cdk_function,
 197   /* An array.  */
 198   cdk_array,
 199   /* A pointer.  */
 200   cdk_pointer,
 201   /* Parenthesized declarator with nested attributes.  */
 202   cdk_attrs
 203 };
 204
 205 /* Information about the parameters in a function declarator.  */
 206 struct c_arg_info {
 207   /* A list of parameter decls.  */
 208   tree parms;
 209   /* A list of structure, union and enum tags defined.  */
 210   tree tags;
 211   /* A list of argument types to go in the FUNCTION_TYPE.  */
 212   tree types;
 213   /* A list of non-parameter decls (notably enumeration constants)
 214      defined with the parameters.  */
 215   tree others;
 216 };
 217
 218 /* A declarator.  */
 219 struct c_declarator {
 220   /* The kind of declarator.  */
 221   enum c_declarator_kind kind;
 222   /* Except for cdk_id, the contained declarator.  For cdk_id, NULL.  */
 223   struct c_declarator *declarator;
 224   union {
 225     /* For identifiers, an IDENTIFIER_NODE or NULL_TREE if an abstract
 226        declarator.  */
 227     tree id;
 228     /* For functions.  */
 229     struct c_arg_info *arg_info;
 230     /* For arrays.  */
 231     struct {
 232       /* The array dimension, or NULL for [] and [*].  */
 233       tree dimen;
 234       /* The qualifiers inside [].  */
 235       int quals;
 236       /* The attributes (currently ignored) inside [].  */
 237       tree attrs;
 238       /* Whether [static] was used.  */
 239       BOOL_BITFIELD static_p : 1;
 240       /* Whether [*] was used.  */
 241       BOOL_BITFIELD vla_unspec_p : 1;
 242     } array;
 243     /* For pointers, the qualifiers on the pointer type.  */
 244     int pointer_quals;
 245     /* For attributes.  */
 246     tree attrs;
 247   } u;
 248 };
 249
 250 /* A type name.  */
 251 struct c_type_name {
 252   /* The declaration specifiers.  */
 253   struct c_declspecs *specs;
 254   /* The declarator.  */
 255   struct c_declarator *declarator;
 256 };
 257
 258 /* A parameter.  */
 259 struct c_parm {
 260   /* The declaration specifiers, minus any prefix attributes.  */
 261   struct c_declspecs *specs;
 262   /* The attributes.  */
 263   tree attrs;
 264   /* The declarator.  */
 265   struct c_declarator *declarator;
 266 };
 267
 268 /* Save and restore the variables in this file and elsewhere
 269    that keep track of the progress of compilation of the current function.
 270    Used for nested functions.  */
 271
 272 struct language_function GTY(())
 273 {
 274   struct c_language_function base;
 275   tree x_break_label;
 276   tree x_cont_label;
 277   struct c_switch * GTY((skip)) x_switch_stack;
 278   struct c_arg_info * GTY((skip)) arg_info;
 279   int returns_value;
 280   int returns_null;
 281   int returns_abnormally;
 282   int warn_about_return_type;
 283   int extern_inline;
 284 };
 285
 286 \f
 287 /* in c-parse.in */
 288 extern void c_parse_init (void);
 289
 290 /* in c-aux-info.c */
 291 extern void gen_aux_info_record (tree, int, int, int);
 292
 293 /* in c-decl.c */
 294 extern struct obstack parser_obstack;
 295 extern tree c_break_label;
 296 extern tree c_cont_label;
 297
 298 extern int global_bindings_p (void);
 299 extern void push_scope (void);
 300 extern tree pop_scope (void);
 301 extern void insert_block (tree);
 302 extern tree pushdecl (tree);
 303 extern void c_expand_body (tree);
 304
 305 extern void c_init_decl_processing (void);
 306 extern void c_dup_lang_specific_decl (tree);
 307 extern void c_print_identifier (FILE *, tree, int);
 308 extern int quals_from_declspecs (const struct c_declspecs *);
 309 extern struct c_declarator *build_array_declarator (tree, struct c_declspecs *,
 310                                                     bool, bool);
 311 extern tree build_enumerator (tree, tree);
 312 extern void check_for_loop_decls (void);
 313 extern void mark_forward_parm_decls (void);
 314 extern int  complete_array_type (tree, tree, int);
 315 extern void declare_parm_level (void);
 316 extern void undeclared_variable (tree);
 317 extern tree declare_label (tree);
 318 extern tree define_label (location_t, tree);
 319 extern void finish_decl (tree, tree, tree);
 320 extern tree finish_enum (tree, tree, tree);
 321 extern void finish_function (void);
 322 extern tree finish_struct (tree, tree, tree);
 323 extern struct c_arg_info *get_parm_info (bool);
 324 extern tree grokfield (struct c_declarator *, struct c_declspecs *, tree);
 325 extern tree groktypename (struct c_type_name *);
 326 extern tree grokparm (const struct c_parm *);
 327 extern tree implicitly_declare (tree);
 328 extern void keep_next_level (void);
 329 extern tree lookup_name (tree);
 330 extern void pending_xref_error (void);
 331 extern void c_push_function_context (struct function *);
 332 extern void c_pop_function_context (struct function *);
 333 extern void push_parm_decl (const struct c_parm *);
 334 extern tree pushdecl_top_level (tree);
 335 extern struct c_declarator *set_array_declarator_inner (struct c_declarator *,
 336                                                         struct c_declarator *,
 337                                                         bool);
 338 extern tree builtin_function (const char *, tree, int, enum built_in_class,
 339                               const char *, tree);
 340 extern void shadow_tag (const struct c_declspecs *);
 341 extern void shadow_tag_warned (const struct c_declspecs *, int);
 342 extern tree start_enum (tree);
 343 extern int  start_function (struct c_declspecs *, struct c_declarator *, tree);
 344 extern tree start_decl (struct c_declarator *, struct c_declspecs *, bool,
 345                         tree);
 346 extern tree start_struct (enum tree_code, tree);
 347 extern void store_parm_decls (void);
 348 extern void store_parm_decls_from (struct c_arg_info *);
 349 extern tree xref_tag (enum tree_code, tree);
 350 extern int c_expand_decl (tree);
 351 extern struct c_parm *build_c_parm (struct c_declspecs *, tree,
 352                                     struct c_declarator *);
 353 extern struct c_declarator *build_attrs_declarator (tree,
 354                                                     struct c_declarator *);
 355 extern struct c_declarator *build_function_declarator (struct c_arg_info *,
 356                                                        struct c_declarator *);
 357 extern struct c_declarator *build_id_declarator (tree);
 358 extern struct c_declarator *make_pointer_declarator (struct c_declspecs *,
 359                                                      struct c_declarator *);
 360 extern struct c_declspecs *build_null_declspecs (void);
 361 extern struct c_declspecs *declspecs_add_qual (struct c_declspecs *, tree);
 362 extern struct c_declspecs *declspecs_add_type (struct c_declspecs *, tree);
 363 extern struct c_declspecs *declspecs_add_scspec (struct c_declspecs *, tree);
 364 extern struct c_declspecs *declspecs_add_attrs (struct c_declspecs *, tree);
 365
 366 /* in c-objc-common.c */
 367 extern int c_disregard_inline_limits (tree);
 368 extern int c_cannot_inline_tree_fn (tree *);
 369 extern bool c_objc_common_init (void);
 370 extern bool c_missing_noreturn_ok_p (tree);
 371 extern tree c_objc_common_truthvalue_conversion (tree expr);
 372 extern int defer_fn (tree);
 373 extern bool c_warn_unused_global_decl (tree);
 374 extern void c_initialize_diagnostics (diagnostic_context *);
 375
 376 #define c_build_type_variant(TYPE, CONST_P, VOLATILE_P)           \
 377   c_build_qualified_type ((TYPE),                                 \
 378                           ((CONST_P) ? TYPE_QUAL_CONST : 0) |     \
 379                           ((VOLATILE_P) ? TYPE_QUAL_VOLATILE : 0))
 380
 381 /* in c-typeck.c */
 382 extern int in_alignof;
 383 extern int in_sizeof;
 384 extern int in_typeof;
 385
 386 extern struct c_switch *c_switch_stack;
 387
 388 extern tree require_complete_type (tree);
 389 extern int same_translation_unit_p (tree, tree);
 390 extern int comptypes (tree, tree);
 391 extern tree c_size_in_bytes (tree);
 392 extern bool c_mark_addressable (tree);
 393 extern void c_incomplete_type_error (tree, tree);
 394 extern tree c_type_promotes_to (tree);
 395 extern tree composite_type (tree, tree);
 396 extern tree build_component_ref (tree, tree);
 397 extern tree build_indirect_ref (tree, const char *);
 398 extern tree build_array_ref (tree, tree);
 399 extern tree build_external_ref (tree, int);
 400 extern void record_maybe_used_decl (tree);
 401 extern void pop_maybe_used (bool);
 402 extern struct c_expr c_expr_sizeof_expr (struct c_expr);
 403 extern struct c_expr c_expr_sizeof_type (struct c_type_name *);
 404 extern struct c_expr parser_build_binary_op (enum tree_code, struct c_expr,
 405                                              struct c_expr);
 406 extern void readonly_error (tree, const char *);
 407 extern tree build_conditional_expr (tree, tree, tree);
 408 extern tree build_compound_expr (tree, tree);
 409 extern tree c_cast_expr (struct c_type_name *, tree);
 410 extern tree build_c_cast (tree, tree);
 411 extern tree build_modify_expr (tree, enum tree_code, tree);
 412 extern void store_init_value (tree, tree);
 413 extern void error_init (const char *);
 414 extern void pedwarn_init (const char *);
 415 extern void maybe_warn_string_init (tree, struct c_expr);
 416 extern void start_init (tree, tree, int);
 417 extern void finish_init (void);
 418 extern void really_start_incremental_init (tree);
 419 extern void push_init_level (int);
 420 extern struct c_expr pop_init_level (int);
 421 extern void set_init_index (tree, tree);
 422 extern void set_init_label (tree);
 423 extern void process_init_element (struct c_expr);
 424 extern tree build_compound_literal (tree, tree);
 425 extern tree c_start_case (tree);
 426 extern void c_finish_case (tree);
 427 extern tree build_asm_expr (tree, tree, tree, tree, bool);
 428 extern tree build_asm_stmt (tree, tree);
 429 extern tree c_convert_parm_for_inlining (tree, tree, tree, int);
 430 extern int c_types_compatible_p (tree, tree);
 431 extern tree c_begin_compound_stmt (bool);
 432 extern tree c_end_compound_stmt (tree, bool);
 433 extern void c_finish_if_stmt (location_t, tree, tree, tree, bool);
 434 extern void c_finish_loop (location_t, tree, tree, tree, tree, tree, bool);
 435 extern tree c_begin_stmt_expr (void);
 436 extern tree c_finish_stmt_expr (tree);
 437 extern tree c_process_expr_stmt (tree);
 438 extern tree c_finish_expr_stmt (tree);
 439 extern tree c_finish_return (tree);
 440 extern tree c_finish_bc_stmt (tree *, bool);
 441 extern tree c_finish_goto_label (tree);
 442 extern tree c_finish_goto_ptr (tree);
 443
 444 /* Set to 0 at beginning of a function definition, set to 1 if
 445    a return statement that specifies a return value is seen.  */
 446
 447 extern int current_function_returns_value;
 448
 449 /* Set to 0 at beginning of a function definition, set to 1 if
 450    a return statement with no argument is seen.  */
 451
 452 extern int current_function_returns_null;
 453
 454 /* Set to 0 at beginning of a function definition, set to 1 if
 455    a call to a noreturn function is seen.  */
 456
 457 extern int current_function_returns_abnormally;
 458
 459 /* Nonzero means we are reading code that came from a system header file.  */
 460
 461 extern int system_header_p;
 462
 463 /* True means global_bindings_p should return false even if the scope stack
 464    says we are in file scope.  */
 465
 466 extern bool c_override_global_bindings_to_false;
 467
 468 /* True means we've initialized exception handling.  */
 469 extern bool c_eh_initialized_p;
 470
 471 /* In c-decl.c */
 472 extern void c_finish_incomplete_decl (tree);
 473 extern void c_write_global_declarations (void);
 474
 475 /* In order for the format checking to accept the C frontend
 476    diagnostic framework extensions, you must include this file before
 477    toplev.h, not after.  */
 478 #define GCC_DIAG_STYLE __gcc_cdiag__
 479 #if GCC_VERSION >= 3005
 480 #define ATTRIBUTE_GCC_CDIAG(m, n) __attribute__ ((__format__ (GCC_DIAG_STYLE, m ,n))) ATTRIBUTE_NONNULL(m)
 481 #else
 482 #define ATTRIBUTE_GCC_CDIAG(m, n) ATTRIBUTE_NONNULL(m)
 483 #endif
 484
 485 extern void pedwarn_c90 (const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2);
 486 extern void pedwarn_c99 (const char *, ...) ATTRIBUTE_GCC_CDIAG(1,2);
 487
 488 #endif /* ! GCC_C_TREE_H */