gcc/c-common.h

   1 /* Definitions for c-common.c.
   2    Copyright (C) 1987, 1993, 1994, 1995, 1997, 1998,
   3    1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007 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 3, 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 COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef GCC_C_COMMON_H
  22 #define GCC_C_COMMON_H
  23
  24 #include "splay-tree.h"
  25 #include "cpplib.h"
  26 #include "ggc.h"
  27
  28 /* Usage of TREE_LANG_FLAG_?:
  29    0: TREE_NEGATED_INT (in INTEGER_CST).
  30       IDENTIFIER_MARKED (used by search routines).
  31       DECL_PRETTY_FUNCTION_P (in VAR_DECL)
  32    1: C_DECLARED_LABEL_FLAG (in LABEL_DECL)
  33       STATEMENT_LIST_STMT_EXPR (in STATEMENT_LIST)
  34    2: unused
  35    3: STATEMENT_LIST_HAS_LABEL (in STATEMENT_LIST)
  36    4: unused
  37 */
  38
  39 /* Reserved identifiers.  This is the union of all the keywords for C,
  40    C++, and Objective-C.  All the type modifiers have to be in one
  41    block at the beginning, because they are used as mask bits.  There
  42    are 27 type modifiers; if we add many more we will have to redesign
  43    the mask mechanism.  */
  44
  45 enum rid
  46 {
  47   /* Modifiers: */
  48   /* C, in empirical order of frequency.  */
  49   RID_STATIC = 0,
  50   RID_UNSIGNED, RID_LONG,    RID_CONST, RID_EXTERN,
  51   RID_REGISTER, RID_TYPEDEF, RID_SHORT, RID_INLINE,
  52   RID_VOLATILE, RID_SIGNED,  RID_AUTO,  RID_RESTRICT,
  53
  54   /* C extensions */
  55   RID_COMPLEX, RID_THREAD, RID_SAT,
  56
  57   /* C++ */
  58   RID_FRIEND, RID_VIRTUAL, RID_EXPLICIT, RID_EXPORT, RID_MUTABLE,
  59
  60   /* ObjC */
  61   RID_IN, RID_OUT, RID_INOUT, RID_BYCOPY, RID_BYREF, RID_ONEWAY,
  62
  63   /* C */
  64   RID_INT,     RID_CHAR,   RID_FLOAT,    RID_DOUBLE, RID_VOID,
  65   RID_ENUM,    RID_STRUCT, RID_UNION,    RID_IF,     RID_ELSE,
  66   RID_WHILE,   RID_DO,     RID_FOR,      RID_SWITCH, RID_CASE,
  67   RID_DEFAULT, RID_BREAK,  RID_CONTINUE, RID_RETURN, RID_GOTO,
  68   RID_SIZEOF,
  69
  70   /* C extensions */
  71   RID_ASM,       RID_TYPEOF,   RID_ALIGNOF,  RID_ATTRIBUTE,  RID_VA_ARG,
  72   RID_EXTENSION, RID_IMAGPART, RID_REALPART, RID_LABEL,      RID_CHOOSE_EXPR,
  73   RID_TYPES_COMPATIBLE_P,
  74   RID_DFLOAT32, RID_DFLOAT64, RID_DFLOAT128,
  75   RID_FRACT, RID_ACCUM,
  76
  77   /* This means to warn that this is a C++ keyword, and then treat it
  78      as a normal identifier.  */
  79   RID_CXX_COMPAT_WARN,
  80
  81   /* Too many ways of getting the name of a function as a string */
  82   RID_FUNCTION_NAME, RID_PRETTY_FUNCTION_NAME, RID_C99_FUNCTION_NAME,
  83
  84   /* C++ */
  85   RID_BOOL,     RID_WCHAR,    RID_CLASS,
  86   RID_PUBLIC,   RID_PRIVATE,  RID_PROTECTED,
  87   RID_TEMPLATE, RID_NULL,     RID_CATCH,
  88   RID_DELETE,   RID_FALSE,    RID_NAMESPACE,
  89   RID_NEW,      RID_OFFSETOF, RID_OPERATOR,
  90   RID_THIS,     RID_THROW,    RID_TRUE,
  91   RID_TRY,      RID_TYPENAME, RID_TYPEID,
  92   RID_USING,    RID_CHAR16,   RID_CHAR32,
  93
  94   /* casts */
  95   RID_CONSTCAST, RID_DYNCAST, RID_REINTCAST, RID_STATCAST,
  96
  97   /* C++ extensions */
  98   RID_HAS_NOTHROW_ASSIGN,      RID_HAS_NOTHROW_CONSTRUCTOR,
  99   RID_HAS_NOTHROW_COPY,        RID_HAS_TRIVIAL_ASSIGN,
 100   RID_HAS_TRIVIAL_CONSTRUCTOR, RID_HAS_TRIVIAL_COPY,
 101   RID_HAS_TRIVIAL_DESTRUCTOR,  RID_HAS_VIRTUAL_DESTRUCTOR,
 102   RID_IS_ABSTRACT,             RID_IS_BASE_OF,
 103   RID_IS_CONVERTIBLE_TO,       RID_IS_CLASS,
 104   RID_IS_EMPTY,                RID_IS_ENUM,
 105   RID_IS_POD,                  RID_IS_POLYMORPHIC,
 106   RID_IS_UNION,
 107
 108   /* C++0x */
 109   RID_STATIC_ASSERT, RID_DECLTYPE,
 110
 111   /* Objective-C */
 112   RID_AT_ENCODE,   RID_AT_END,
 113   RID_AT_CLASS,    RID_AT_ALIAS,     RID_AT_DEFS,
 114   RID_AT_PRIVATE,  RID_AT_PROTECTED, RID_AT_PUBLIC,
 115   RID_AT_PROTOCOL, RID_AT_SELECTOR,
 116   RID_AT_THROW,    RID_AT_TRY,       RID_AT_CATCH,
 117   RID_AT_FINALLY,  RID_AT_SYNCHRONIZED,
 118   RID_AT_INTERFACE,
 119   RID_AT_IMPLEMENTATION,
 120
 121   RID_MAX,
 122
 123   RID_FIRST_MODIFIER = RID_STATIC,
 124   RID_LAST_MODIFIER = RID_ONEWAY,
 125
 126   RID_FIRST_CXX0X = RID_STATIC_ASSERT,
 127   RID_LAST_CXX0X = RID_DECLTYPE,
 128   RID_FIRST_AT = RID_AT_ENCODE,
 129   RID_LAST_AT = RID_AT_IMPLEMENTATION,
 130   RID_FIRST_PQ = RID_IN,
 131   RID_LAST_PQ = RID_ONEWAY
 132 };
 133
 134 #define OBJC_IS_AT_KEYWORD(rid) \
 135   ((unsigned int) (rid) >= (unsigned int) RID_FIRST_AT && \
 136    (unsigned int) (rid) <= (unsigned int) RID_LAST_AT)
 137
 138 #define OBJC_IS_PQ_KEYWORD(rid) \
 139   ((unsigned int) (rid) >= (unsigned int) RID_FIRST_PQ && \
 140    (unsigned int) (rid) <= (unsigned int) RID_LAST_PQ)
 141
 142 /* The elements of `ridpointers' are identifier nodes for the reserved
 143    type names and storage classes.  It is indexed by a RID_... value.  */
 144 extern GTY ((length ("(int) RID_MAX"))) tree *ridpointers;
 145
 146 /* Standard named or nameless data types of the C compiler.  */
 147
 148 enum c_tree_index
 149 {
 150     CTI_CHAR16_TYPE,
 151     CTI_CHAR32_TYPE,
 152     CTI_WCHAR_TYPE,
 153     CTI_SIGNED_WCHAR_TYPE,
 154     CTI_UNSIGNED_WCHAR_TYPE,
 155     CTI_WINT_TYPE,
 156     CTI_SIGNED_SIZE_TYPE, /* For format checking only.  */
 157     CTI_UNSIGNED_PTRDIFF_TYPE, /* For format checking only.  */
 158     CTI_INTMAX_TYPE,
 159     CTI_UINTMAX_TYPE,
 160     CTI_WIDEST_INT_LIT_TYPE,
 161     CTI_WIDEST_UINT_LIT_TYPE,
 162
 163     CTI_CHAR_ARRAY_TYPE,
 164     CTI_CHAR16_ARRAY_TYPE,
 165     CTI_CHAR32_ARRAY_TYPE,
 166     CTI_WCHAR_ARRAY_TYPE,
 167     CTI_INT_ARRAY_TYPE,
 168     CTI_STRING_TYPE,
 169     CTI_CONST_STRING_TYPE,
 170
 171     /* Type for boolean expressions (bool in C++, int in C).  */
 172     CTI_TRUTHVALUE_TYPE,
 173     CTI_TRUTHVALUE_TRUE,
 174     CTI_TRUTHVALUE_FALSE,
 175
 176     CTI_DEFAULT_FUNCTION_TYPE,
 177
 178     /* These are not types, but we have to look them up all the time.  */
 179     CTI_FUNCTION_NAME_DECL,
 180     CTI_PRETTY_FUNCTION_NAME_DECL,
 181     CTI_C99_FUNCTION_NAME_DECL,
 182     CTI_SAVED_FUNCTION_NAME_DECLS,
 183
 184     CTI_VOID_ZERO,
 185
 186     CTI_NULL,
 187
 188     CTI_MAX
 189 };
 190
 191 #define C_CPP_HASHNODE(id) \
 192   (&(((struct c_common_identifier *) (id))->node))
 193 #define C_RID_CODE(id) \
 194   ((enum rid) (((struct c_common_identifier *) (id))->node.rid_code))
 195 #define C_SET_RID_CODE(id, code) \
 196   (((struct c_common_identifier *) (id))->node.rid_code = (unsigned char) code)
 197
 198 /* Identifier part common to the C front ends.  Inherits from
 199    tree_identifier, despite appearances.  */
 200 struct c_common_identifier GTY(())
 201 {
 202   struct tree_common common;
 203   struct cpp_hashnode node;
 204 };
 205
 206 /* An entry in the reserved keyword table.  */
 207
 208 struct c_common_resword
 209 {
 210   const char *const word;
 211   ENUM_BITFIELD(rid) const rid : 16;
 212   const unsigned int disable   : 16;
 213 };
 214
 215 /* Disable mask.  Keywords are disabled if (reswords[i].disable &
 216    mask) is _true_.  Thus for keywords which are present in all
 217    languages the disable field is zero.  */
 218
 219 #define D_CONLY         0x001   /* C only (not in C++).  */
 220 #define D_CXXONLY       0x002   /* C++ only (not in C).  */
 221 #define D_C99           0x004   /* In C, C99 only.  */
 222 #define D_CXX0X         0x008   /* In C++, C++0X only.  */
 223 #define D_EXT           0x010   /* GCC extension.  */
 224 #define D_EXT89         0x020   /* GCC extension incorporated in C99.  */
 225 #define D_ASM           0x040   /* Disabled by -fno-asm.  */
 226 #define D_OBJC          0x080   /* In Objective C and neither C nor C++.  */
 227 #define D_CXX_OBJC      0x100   /* In Objective C, and C++, but not C.  */
 228 #define D_CXXWARN       0x200   /* In C warn with -Wcxx-compat.  */
 229
 230 /* The reserved keyword table.  */
 231 extern const struct c_common_resword c_common_reswords[];
 232
 233 /* The number of items in the reserved keyword table.  */
 234 extern const unsigned int num_c_common_reswords;
 235
 236 #define char16_type_node                c_global_trees[CTI_CHAR16_TYPE]
 237 #define char32_type_node                c_global_trees[CTI_CHAR32_TYPE]
 238 #define wchar_type_node                 c_global_trees[CTI_WCHAR_TYPE]
 239 #define signed_wchar_type_node          c_global_trees[CTI_SIGNED_WCHAR_TYPE]
 240 #define unsigned_wchar_type_node        c_global_trees[CTI_UNSIGNED_WCHAR_TYPE]
 241 #define wint_type_node                  c_global_trees[CTI_WINT_TYPE]
 242 #define signed_size_type_node           c_global_trees[CTI_SIGNED_SIZE_TYPE]
 243 #define unsigned_ptrdiff_type_node      c_global_trees[CTI_UNSIGNED_PTRDIFF_TYPE]
 244 #define intmax_type_node                c_global_trees[CTI_INTMAX_TYPE]
 245 #define uintmax_type_node               c_global_trees[CTI_UINTMAX_TYPE]
 246 #define widest_integer_literal_type_node c_global_trees[CTI_WIDEST_INT_LIT_TYPE]
 247 #define widest_unsigned_literal_type_node c_global_trees[CTI_WIDEST_UINT_LIT_TYPE]
 248
 249 #define truthvalue_type_node            c_global_trees[CTI_TRUTHVALUE_TYPE]
 250 #define truthvalue_true_node            c_global_trees[CTI_TRUTHVALUE_TRUE]
 251 #define truthvalue_false_node           c_global_trees[CTI_TRUTHVALUE_FALSE]
 252
 253 #define char_array_type_node            c_global_trees[CTI_CHAR_ARRAY_TYPE]
 254 #define char16_array_type_node          c_global_trees[CTI_CHAR16_ARRAY_TYPE]
 255 #define char32_array_type_node          c_global_trees[CTI_CHAR32_ARRAY_TYPE]
 256 #define wchar_array_type_node           c_global_trees[CTI_WCHAR_ARRAY_TYPE]
 257 #define int_array_type_node             c_global_trees[CTI_INT_ARRAY_TYPE]
 258 #define string_type_node                c_global_trees[CTI_STRING_TYPE]
 259 #define const_string_type_node          c_global_trees[CTI_CONST_STRING_TYPE]
 260
 261 #define default_function_type           c_global_trees[CTI_DEFAULT_FUNCTION_TYPE]
 262
 263 #define function_name_decl_node         c_global_trees[CTI_FUNCTION_NAME_DECL]
 264 #define pretty_function_name_decl_node  c_global_trees[CTI_PRETTY_FUNCTION_NAME_DECL]
 265 #define c99_function_name_decl_node             c_global_trees[CTI_C99_FUNCTION_NAME_DECL]
 266 #define saved_function_name_decls       c_global_trees[CTI_SAVED_FUNCTION_NAME_DECLS]
 267
 268 /* A node for `((void) 0)'.  */
 269 #define void_zero_node                  c_global_trees[CTI_VOID_ZERO]
 270
 271 /* The node for C++ `__null'.  */
 272 #define null_node                       c_global_trees[CTI_NULL]
 273
 274 extern GTY(()) tree c_global_trees[CTI_MAX];
 275
 276 /* In a RECORD_TYPE, a sorted array of the fields of the type, not a
 277    tree for size reasons.  */
 278 struct sorted_fields_type GTY(())
 279 {
 280   int len;
 281   tree GTY((length ("%h.len"))) elts[1];
 282 };
 283
 284 /* Mark which labels are explicitly declared.
 285    These may be shadowed, and may be referenced from nested functions.  */
 286 #define C_DECLARED_LABEL_FLAG(label) TREE_LANG_FLAG_1 (label)
 287
 288 typedef enum c_language_kind
 289 {
 290   clk_c         = 0,            /* C90, C94 or C99 */
 291   clk_objc      = 1,            /* clk_c with ObjC features.  */
 292   clk_cxx       = 2,            /* ANSI/ISO C++ */
 293   clk_objcxx    = 3             /* clk_cxx with ObjC features.  */
 294 }
 295 c_language_kind;
 296
 297 /* To test for a specific language use c_language, defined by each
 298    front end.  For "ObjC features" or "not C++" use the macros.  */
 299 extern c_language_kind c_language;
 300
 301 #define c_dialect_cxx()         (c_language & clk_cxx)
 302 #define c_dialect_objc()        (c_language & clk_objc)
 303
 304 /* Information about a statement tree.  */
 305
 306 struct stmt_tree_s GTY(()) {
 307   /* The current statement list being collected.  */
 308   tree x_cur_stmt_list;
 309
 310   /* In C++, Nonzero if we should treat statements as full
 311      expressions.  In particular, this variable is no-zero if at the
 312      end of a statement we should destroy any temporaries created
 313      during that statement.  Similarly, if, at the end of a block, we
 314      should destroy any local variables in this block.  Normally, this
 315      variable is nonzero, since those are the normal semantics of
 316      C++.
 317
 318      However, in order to represent aggregate initialization code as
 319      tree structure, we use statement-expressions.  The statements
 320      within the statement expression should not result in cleanups
 321      being run until the entire enclosing statement is complete.
 322
 323      This flag has no effect in C.  */
 324   int stmts_are_full_exprs_p;
 325 };
 326
 327 typedef struct stmt_tree_s *stmt_tree;
 328
 329 /* Global state pertinent to the current function.  Some C dialects
 330    extend this structure with additional fields.  */
 331
 332 struct c_language_function GTY(()) {
 333   /* While we are parsing the function, this contains information
 334      about the statement-tree that we are building.  */
 335   struct stmt_tree_s x_stmt_tree;
 336 };
 337
 338 /* When building a statement-tree, this is the current statement list
 339    being collected.  It's TREE_CHAIN is a back-pointer to the previous
 340    statement list.  */
 341
 342 #define cur_stmt_list (current_stmt_tree ()->x_cur_stmt_list)
 343
 344 /* Language-specific hooks.  */
 345
 346 /* If non-NULL, this function is called after a precompile header file
 347    is loaded.  */
 348 extern void (*lang_post_pch_load) (void);
 349
 350 extern void push_file_scope (void);
 351 extern void pop_file_scope (void);
 352 extern stmt_tree current_stmt_tree (void);
 353 extern tree push_stmt_list (void);
 354 extern tree pop_stmt_list (tree);
 355 extern tree add_stmt (tree);
 356 extern void push_cleanup (tree, tree, bool);
 357 extern tree pushdecl_top_level (tree);
 358 extern tree pushdecl (tree);
 359 extern tree build_modify_expr (tree, enum tree_code, tree);
 360 extern tree build_indirect_ref (tree, const char *);
 361
 362 extern int c_expand_decl (tree);
 363
 364 extern int field_decl_cmp (const void *, const void *);
 365 extern void resort_sorted_fields (void *, void *, gt_pointer_operator,
 366                                   void *);
 367 extern bool has_c_linkage (const_tree decl);
 368 \f
 369 /* Switches common to the C front ends.  */
 370
 371 /* Nonzero if prepreprocessing only.  */
 372
 373 extern int flag_preprocess_only;
 374
 375 /* Zero means that faster, ...NonNil variants of objc_msgSend...
 376    calls will be used in ObjC; passing nil receivers to such calls
 377    will most likely result in crashes.  */
 378 extern int flag_nil_receivers;
 379
 380 /* Nonzero means that we will allow new ObjC exception syntax (@throw,
 381    @try, etc.) in source code.  */
 382 extern int flag_objc_exceptions;
 383
 384 /* Nonzero means that we generate NeXT setjmp based exceptions.  */
 385 extern int flag_objc_sjlj_exceptions;
 386
 387 /* Nonzero means that code generation will be altered to support
 388    "zero-link" execution.  This currently affects ObjC only, but may
 389    affect other languages in the future.  */
 390 extern int flag_zero_link;
 391
 392 /* Nonzero means emit an '__OBJC, __image_info' for the current translation
 393    unit.  It will inform the ObjC runtime that class definition(s) herein
 394    contained are to replace one(s) previously loaded.  */
 395 extern int flag_replace_objc_classes;
 396
 397 /* Nonzero means don't output line number information.  */
 398
 399 extern char flag_no_line_commands;
 400
 401 /* Nonzero causes -E output not to be done, but directives such as
 402    #define that have side effects are still obeyed.  */
 403
 404 extern char flag_no_output;
 405
 406 /* Nonzero means dump macros in some fashion; contains the 'D', 'M',
 407    'N' or 'U' of the command line switch.  */
 408
 409 extern char flag_dump_macros;
 410
 411 /* Nonzero means pass #include lines through to the output.  */
 412
 413 extern char flag_dump_includes;
 414
 415 /* Nonzero means process PCH files while preprocessing.  */
 416
 417 extern bool flag_pch_preprocess;
 418
 419 /* The file name to which we should write a precompiled header, or
 420    NULL if no header will be written in this compile.  */
 421
 422 extern const char *pch_file;
 423
 424 /* Nonzero if an ISO standard was selected.  It rejects macros in the
 425    user's namespace.  */
 426
 427 extern int flag_iso;
 428
 429 /* Nonzero if -undef was given.  It suppresses target built-in macros
 430    and assertions.  */
 431
 432 extern int flag_undef;
 433
 434 /* Nonzero means don't recognize the non-ANSI builtin functions.  */
 435
 436 extern int flag_no_builtin;
 437
 438 /* Nonzero means don't recognize the non-ANSI builtin functions.
 439    -ansi sets this.  */
 440
 441 extern int flag_no_nonansi_builtin;
 442
 443 /* Nonzero means give `double' the same size as `float'.  */
 444
 445 extern int flag_short_double;
 446
 447 /* Nonzero means give `wchar_t' the same size as `short'.  */
 448
 449 extern int flag_short_wchar;
 450
 451 /* Nonzero means allow implicit conversions between vectors with
 452    differing numbers of subparts and/or differing element types.  */
 453 extern int flag_lax_vector_conversions;
 454
 455 /* Nonzero means allow Microsoft extensions without warnings or errors.  */
 456 extern int flag_ms_extensions;
 457
 458 /* Nonzero means don't recognize the keyword `asm'.  */
 459
 460 extern int flag_no_asm;
 461
 462 /* Nonzero means give string constants the type `const char *', as mandated
 463    by the standard.  */
 464
 465 extern int flag_const_strings;
 466
 467 /* Nonzero means to treat bitfields as signed unless they say `unsigned'.  */
 468
 469 extern int flag_signed_bitfields;
 470
 471 /* Warn about #pragma directives that are not recognized.  */
 472
 473 extern int warn_unknown_pragmas; /* Tri state variable.  */
 474
 475 /* Warn about format/argument anomalies in calls to formatted I/O functions
 476    (*printf, *scanf, strftime, strfmon, etc.).  */
 477
 478 extern int warn_format;
 479
 480
 481 /* C/ObjC language option variables.  */
 482
 483
 484 /* Nonzero means allow type mismatches in conditional expressions;
 485    just make their values `void'.  */
 486
 487 extern int flag_cond_mismatch;
 488
 489 /* Nonzero means enable C89 Amendment 1 features.  */
 490
 491 extern int flag_isoc94;
 492
 493 /* Nonzero means use the ISO C99 dialect of C.  */
 494
 495 extern int flag_isoc99;
 496
 497 /* Nonzero means that we have builtin functions, and main is an int.  */
 498
 499 extern int flag_hosted;
 500
 501 /* Warn if main is suspicious.  */
 502
 503 extern int warn_main;
 504
 505
 506 /* ObjC language option variables.  */
 507
 508
 509 /* Open and close the file for outputting class declarations, if
 510    requested (ObjC).  */
 511
 512 extern int flag_gen_declaration;
 513
 514 /* Tells the compiler that this is a special run.  Do not perform any
 515    compiling, instead we are to test some platform dependent features
 516    and output a C header file with appropriate definitions.  */
 517
 518 extern int print_struct_values;
 519
 520 /* ???.  Undocumented.  */
 521
 522 extern const char *constant_string_class_name;
 523
 524
 525 /* C++ language option variables.  */
 526
 527
 528 /* Nonzero means don't recognize any extension keywords.  */
 529
 530 extern int flag_no_gnu_keywords;
 531
 532 /* Nonzero means do emit exported implementations of functions even if
 533    they can be inlined.  */
 534
 535 extern int flag_implement_inlines;
 536
 537 /* Nonzero means that implicit instantiations will be emitted if needed.  */
 538
 539 extern int flag_implicit_templates;
 540
 541 /* Nonzero means that implicit instantiations of inline templates will be
 542    emitted if needed, even if instantiations of non-inline templates
 543    aren't.  */
 544
 545 extern int flag_implicit_inline_templates;
 546
 547 /* Nonzero means generate separate instantiation control files and
 548    juggle them at link time.  */
 549
 550 extern int flag_use_repository;
 551
 552 /* Nonzero if we want to issue diagnostics that the standard says are not
 553    required.  */
 554
 555 extern int flag_optional_diags;
 556
 557 /* Nonzero means we should attempt to elide constructors when possible.  */
 558
 559 extern int flag_elide_constructors;
 560
 561 /* Nonzero means that member functions defined in class scope are
 562    inline by default.  */
 563
 564 extern int flag_default_inline;
 565
 566 /* Controls whether compiler generates 'type descriptor' that give
 567    run-time type information.  */
 568
 569 extern int flag_rtti;
 570
 571 /* Nonzero if we want to conserve space in the .o files.  We do this
 572    by putting uninitialized data and runtime initialized data into
 573    .common instead of .data at the expense of not flagging multiple
 574    definitions.  */
 575
 576 extern int flag_conserve_space;
 577
 578 /* Nonzero if we want to obey access control semantics.  */
 579
 580 extern int flag_access_control;
 581
 582 /* Nonzero if we want to check the return value of new and avoid calling
 583    constructors if it is a null pointer.  */
 584
 585 extern int flag_check_new;
 586
 587 /* The supported C++ dialects.  */
 588
 589 enum cxx_dialect {
 590   /* C++98  */
 591   cxx98,
 592   /* Experimental features that are likely to become part of
 593      C++0x.  */
 594   cxx0x
 595 };
 596
 597 /* The C++ dialect being used. C++98 is the default.  */
 598 extern enum cxx_dialect cxx_dialect;
 599
 600 /* Nonzero if we want the new ISO rules for pushing a new scope for `for'
 601    initialization variables.
 602    0: Old rules, set by -fno-for-scope.
 603    2: New ISO rules, set by -ffor-scope.
 604    1: Try to implement new ISO rules, but with backup compatibility
 605    (and warnings).  This is the default, for now.  */
 606
 607 extern int flag_new_for_scope;
 608
 609 /* Nonzero if we want to emit defined symbols with common-like linkage as
 610    weak symbols where possible, in order to conform to C++ semantics.
 611    Otherwise, emit them as local symbols.  */
 612
 613 extern int flag_weak;
 614
 615 /* 0 means we want the preprocessor to not emit line directives for
 616    the current working directory.  1 means we want it to do it.  -1
 617    means we should decide depending on whether debugging information
 618    is being emitted or not.  */
 619
 620 extern int flag_working_directory;
 621
 622 /* Nonzero to use __cxa_atexit, rather than atexit, to register
 623    destructors for local statics and global objects.  */
 624
 625 extern int flag_use_cxa_atexit;
 626
 627 /* Nonzero to use __cxa_get_exception_ptr in the C++ exception-handling
 628    logic.  */
 629
 630 extern int flag_use_cxa_get_exception_ptr;
 631
 632 /* Nonzero means to implement standard semantics for exception
 633    specifications, calling unexpected if an exception is thrown that
 634    doesn't match the specification.  Zero means to treat them as
 635    assertions and optimize accordingly, but not check them.  */
 636
 637 extern int flag_enforce_eh_specs;
 638
 639 /* Nonzero (the default) means to generate thread-safe code for
 640    initializing local statics.  */
 641
 642 extern int flag_threadsafe_statics;
 643
 644 /* Nonzero means warn about implicit declarations.  */
 645
 646 extern int warn_implicit;
 647
 648 /* Warn about using __null (as NULL in C++) as sentinel.  For code compiled
 649    with GCC this doesn't matter as __null is guaranteed to have the right
 650    size.  */
 651
 652 extern int warn_strict_null_sentinel;
 653
 654 /* Maximum template instantiation depth.  This limit is rather
 655    arbitrary, but it exists to limit the time it takes to notice
 656    infinite template instantiations.  */
 657
 658 extern int max_tinst_depth;
 659
 660 /* Nonzero means the expression being parsed will never be evaluated.
 661    This is a count, since unevaluated expressions can nest.  */
 662
 663 extern int skip_evaluation;
 664
 665 /* C types are partitioned into three subsets: object, function, and
 666    incomplete types.  */
 667 #define C_TYPE_OBJECT_P(type) \
 668   (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type))
 669
 670 #define C_TYPE_INCOMPLETE_P(type) \
 671   (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type) == 0)
 672
 673 #define C_TYPE_FUNCTION_P(type) \
 674   (TREE_CODE (type) == FUNCTION_TYPE)
 675
 676 /* For convenience we define a single macro to identify the class of
 677    object or incomplete types.  */
 678 #define C_TYPE_OBJECT_OR_INCOMPLETE_P(type) \
 679   (!C_TYPE_FUNCTION_P (type))
 680
 681 /* Attribute table common to the C front ends.  */
 682 extern const struct attribute_spec c_common_attribute_table[];
 683 extern const struct attribute_spec c_common_format_attribute_table[];
 684
 685 /* Pointer to function to lazily generate the VAR_DECL for __FUNCTION__ etc.
 686    ID is the identifier to use, NAME is the string.
 687    TYPE_DEP indicates whether it depends on type of the function or not
 688    (i.e. __PRETTY_FUNCTION__).  */
 689
 690 extern tree (*make_fname_decl) (tree, int);
 691
 692 extern tree identifier_global_value (tree);
 693 extern void record_builtin_type (enum rid, const char *, tree);
 694 extern tree build_void_list_node (void);
 695 extern void start_fname_decls (void);
 696 extern void finish_fname_decls (void);
 697 extern const char *fname_as_string (int);
 698 extern tree fname_decl (unsigned, tree);
 699
 700 extern void check_function_arguments (tree, int, tree *, tree);
 701 extern void check_function_arguments_recurse (void (*)
 702                                               (void *, tree,
 703                                                unsigned HOST_WIDE_INT),
 704                                               void *, tree,
 705                                               unsigned HOST_WIDE_INT);
 706 extern bool check_builtin_function_arguments (tree, int, tree *);
 707 extern void check_function_format (tree, int, tree *);
 708 extern void set_Wformat (int);
 709 extern tree handle_format_attribute (tree *, tree, tree, int, bool *);
 710 extern tree handle_format_arg_attribute (tree *, tree, tree, int, bool *);
 711 extern int c_common_handle_option (size_t code, const char *arg, int value);
 712 extern bool c_common_missing_argument (const char *opt, size_t code);
 713 extern tree c_common_type_for_mode (enum machine_mode, int);
 714 extern tree c_common_type_for_size (unsigned int, int);
 715 extern tree c_common_fixed_point_type_for_size (unsigned int, unsigned int,
 716                                                 int, int);
 717 extern tree c_common_unsigned_type (tree);
 718 extern tree c_common_signed_type (tree);
 719 extern tree c_common_signed_or_unsigned_type (int, tree);
 720 extern tree c_build_bitfield_integer_type (unsigned HOST_WIDE_INT, int);
 721 extern bool decl_with_nonnull_addr_p (const_tree);
 722 extern tree c_common_truthvalue_conversion (tree);
 723 extern void c_apply_type_quals_to_decl (int, tree);
 724 extern tree c_sizeof_or_alignof_type (tree, bool, int);
 725 extern tree c_alignof_expr (tree);
 726 /* Print an error message for invalid operands to arith operation CODE.
 727    NOP_EXPR is used as a special case (see truthvalue_conversion).  */
 728 extern void binary_op_error (enum tree_code, tree, tree);
 729 extern tree fix_string_type (tree);
 730 struct varray_head_tag;
 731 extern void constant_expression_warning (tree);
 732 extern void constant_expression_error (tree);
 733 extern bool strict_aliasing_warning (tree, tree, tree);
 734 extern void empty_if_body_warning (tree, tree);
 735 extern void warnings_for_convert_and_check (tree, tree, tree);
 736 extern tree convert_and_check (tree, tree);
 737 extern void overflow_warning (tree);
 738 extern void warn_logical_operator (enum tree_code, tree, tree);
 739 extern void check_main_parameter_types (tree decl);
 740 extern bool c_determine_visibility (tree);
 741 extern bool same_scalar_type_ignoring_signedness (tree, tree);
 742
 743 #define c_sizeof(T)  c_sizeof_or_alignof_type (T, true, 1)
 744 #define c_alignof(T) c_sizeof_or_alignof_type (T, false, 1)
 745
 746 /* Subroutine of build_binary_op, used for comparison operations.
 747    See if the operands have both been converted from subword integer types
 748    and, if so, perhaps change them both back to their original type.  */
 749 extern tree shorten_compare (tree *, tree *, tree *, enum tree_code *);
 750
 751 extern tree pointer_int_sum (enum tree_code, tree, tree);
 752 extern unsigned int min_precision (tree, int);
 753
 754 /* Add qualifiers to a type, in the fashion for C.  */
 755 extern tree c_build_qualified_type (tree, int);
 756
 757 /* Build tree nodes and builtin functions common to both C and C++ language
 758    frontends.  */
 759 extern void c_common_nodes_and_builtins (void);
 760
 761 extern void set_builtin_user_assembler_name (tree decl, const char *asmspec);
 762
 763 extern void disable_builtin_function (const char *);
 764
 765 extern void set_compound_literal_name (tree decl);
 766
 767 extern tree build_va_arg (tree, tree);
 768
 769 extern unsigned int c_common_init_options (unsigned int, const char **);
 770 extern bool c_common_post_options (const char **);
 771 extern bool c_common_init (void);
 772 extern void c_common_finish (void);
 773 extern void c_common_parse_file (int);
 774 extern alias_set_type c_common_get_alias_set (tree);
 775 extern void c_register_builtin_type (tree, const char*);
 776 extern bool c_promoting_integer_type_p (const_tree);
 777 extern int self_promoting_args_p (const_tree);
 778 extern tree strip_pointer_operator (tree);
 779 extern tree strip_pointer_or_array_types (tree);
 780 extern HOST_WIDE_INT c_common_to_target_charset (HOST_WIDE_INT);
 781
 782 /* This is the basic parsing function.  */
 783 extern void c_parse_file (void);
 784 /* This is misnamed, it actually performs end-of-compilation processing.  */
 785 extern void finish_file (void);
 786
 787
 788 /* These macros provide convenient access to the various _STMT nodes.  */
 789
 790 /* Nonzero if a given STATEMENT_LIST represents the outermost binding
 791    if a statement expression.  */
 792 #define STATEMENT_LIST_STMT_EXPR(NODE) \
 793   TREE_LANG_FLAG_1 (STATEMENT_LIST_CHECK (NODE))
 794
 795 /* Nonzero if a label has been added to the statement list.  */
 796 #define STATEMENT_LIST_HAS_LABEL(NODE) \
 797   TREE_LANG_FLAG_3 (STATEMENT_LIST_CHECK (NODE))
 798
 799 /* COMPOUND_LITERAL_EXPR accessors.  */
 800 #define COMPOUND_LITERAL_EXPR_DECL_STMT(NODE)           \
 801   TREE_OPERAND (COMPOUND_LITERAL_EXPR_CHECK (NODE), 0)
 802 #define COMPOUND_LITERAL_EXPR_DECL(NODE)                        \
 803   DECL_EXPR_DECL (COMPOUND_LITERAL_EXPR_DECL_STMT (NODE))
 804
 805 extern int anon_aggr_type_p (const_tree);
 806
 807 /* For a VAR_DECL that is an anonymous union, these are the various
 808    sub-variables that make up the anonymous union.  */
 809 #define DECL_ANON_UNION_ELEMS(NODE) DECL_ARGUMENTS ((NODE))
 810
 811 /* In a FIELD_DECL, nonzero if the decl was originally a bitfield.  */
 812 #define DECL_C_BIT_FIELD(NODE) \
 813   (DECL_LANG_FLAG_4 (FIELD_DECL_CHECK (NODE)) == 1)
 814 #define SET_DECL_C_BIT_FIELD(NODE) \
 815   (DECL_LANG_FLAG_4 (FIELD_DECL_CHECK (NODE)) = 1)
 816 #define CLEAR_DECL_C_BIT_FIELD(NODE) \
 817   (DECL_LANG_FLAG_4 (FIELD_DECL_CHECK (NODE)) = 0)
 818
 819 extern void emit_local_var (tree);
 820 extern tree do_case (tree, tree);
 821 extern tree build_stmt (enum tree_code, ...);
 822 extern tree build_case_label (tree, tree, tree);
 823
 824 /* These functions must be defined by each front-end which implements
 825    a variant of the C language.  They are used in c-common.c.  */
 826
 827 extern tree build_unary_op (enum tree_code, tree, int);
 828 extern tree build_binary_op (enum tree_code, tree, tree, int);
 829 extern tree perform_integral_promotions (tree);
 830
 831 /* These functions must be defined by each front-end which implements
 832    a variant of the C language.  They are used by port files.  */
 833
 834 extern tree default_conversion (tree);
 835
 836 /* Given two integer or real types, return the type for their sum.
 837    Given two compatible ANSI C types, returns the merged type.  */
 838
 839 extern tree common_type (tree, tree);
 840
 841 extern tree decl_constant_value (tree);
 842
 843 /* Handle increment and decrement of boolean types.  */
 844 extern tree boolean_increment (enum tree_code, tree);
 845
 846 extern int case_compare (splay_tree_key, splay_tree_key);
 847
 848 extern tree c_add_case_label (splay_tree, tree, tree, tree, tree);
 849
 850 extern void c_do_switch_warnings (splay_tree, location_t, tree, tree);
 851
 852 extern tree build_function_call (tree, tree);
 853
 854 extern tree resolve_overloaded_builtin (tree, tree);
 855
 856 extern tree finish_label_address_expr (tree);
 857
 858 /* Same function prototype, but the C and C++ front ends have
 859    different implementations.  Used in c-common.c.  */
 860 extern tree lookup_label (tree);
 861 extern tree lookup_name (tree);
 862
 863 extern bool vector_targets_convertible_p (const_tree t1, const_tree t2);
 864 extern bool vector_types_convertible_p (const_tree t1, const_tree t2, bool emit_lax_note);
 865
 866 extern rtx c_expand_expr (tree, rtx, enum machine_mode, int, rtx *);
 867
 868 extern tree c_staticp (tree);
 869
 870 extern void init_c_lex (void);
 871
 872 extern void c_cpp_builtins (cpp_reader *);
 873 extern void c_cpp_builtins_optimize_pragma (cpp_reader *, tree, tree);
 874
 875 /* Positive if an implicit `extern "C"' scope has just been entered;
 876    negative if such a scope has just been exited.  */
 877 extern GTY(()) int pending_lang_change;
 878
 879 /* Information recorded about each file examined during compilation.  */
 880
 881 struct c_fileinfo
 882 {
 883   int time;     /* Time spent in the file.  */
 884
 885   /* Flags used only by C++.
 886      INTERFACE_ONLY nonzero means that we are in an "interface" section
 887      of the compiler.  INTERFACE_UNKNOWN nonzero means we cannot trust
 888      the value of INTERFACE_ONLY.  If INTERFACE_UNKNOWN is zero and
 889      INTERFACE_ONLY is zero, it means that we are responsible for
 890      exporting definitions that others might need.  */
 891   short interface_only;
 892   short interface_unknown;
 893 };
 894
 895 struct c_fileinfo *get_fileinfo (const char *);
 896 extern void dump_time_statistics (void);
 897
 898 extern bool c_dump_tree (void *, tree);
 899
 900 extern void c_warn_unused_result (gimple_seq);
 901
 902 extern void verify_sequence_points (tree);
 903
 904 extern tree fold_offsetof (tree, tree);
 905
 906 /* Places where an lvalue, or modifiable lvalue, may be required.
 907    Used to select diagnostic messages in lvalue_error and
 908    readonly_error.  */
 909 enum lvalue_use {
 910   lv_assign,
 911   lv_increment,
 912   lv_decrement,
 913   lv_addressof,
 914   lv_asm
 915 };
 916
 917 extern void lvalue_error (enum lvalue_use);
 918
 919 extern int complete_array_type (tree *, tree, bool);
 920
 921 extern tree builtin_type_for_size (int, bool);
 922
 923 extern void warn_array_subscript_with_type_char (tree);
 924 extern void warn_about_parentheses (enum tree_code, enum tree_code,
 925                                     enum tree_code);
 926 extern void warn_for_unused_label (tree label);
 927 extern void warn_for_div_by_zero (tree divisor);
 928
 929 /* In c-gimplify.c  */
 930 extern void c_genericize (tree);
 931 extern int c_gimplify_expr (tree *, gimple_seq *, gimple_seq *);
 932 extern tree c_build_bind_expr (tree, tree);
 933
 934 /* In c-pch.c  */
 935 extern void pch_init (void);
 936 extern int c_common_valid_pch (cpp_reader *pfile, const char *name, int fd);
 937 extern void c_common_read_pch (cpp_reader *pfile, const char *name, int fd,
 938                                const char *orig);
 939 extern void c_common_write_pch (void);
 940 extern void c_common_no_more_pch (void);
 941 extern void c_common_pch_pragma (cpp_reader *pfile, const char *);
 942 extern void c_common_print_pch_checksum (FILE *f);
 943
 944 /* In *-checksum.c */
 945 extern const unsigned char executable_checksum[16];
 946
 947 /* In c-cppbuiltin.c  */
 948 extern void builtin_define_std (const char *macro);
 949 extern void builtin_define_with_value (const char *, const char *, int);
 950 extern void c_stddef_cpp_builtins (void);
 951 extern void fe_file_change (const struct line_map *);
 952 extern void c_parse_error (const char *, enum cpp_ttype, tree);
 953
 954 /* Objective-C / Objective-C++ entry points.  */
 955
 956 /* The following ObjC/ObjC++ functions are called by the C and/or C++
 957    front-ends; they all must have corresponding stubs in stub-objc.c.  */
 958 extern tree objc_is_class_name (tree);
 959 extern tree objc_is_object_ptr (tree);
 960 extern void objc_check_decl (tree);
 961 extern int objc_is_reserved_word (tree);
 962 extern bool objc_compare_types (tree, tree, int, tree);
 963 extern void objc_volatilize_decl (tree);
 964 extern bool objc_type_quals_match (tree, tree);
 965 extern tree objc_rewrite_function_call (tree, tree);
 966 extern tree objc_message_selector (void);
 967 extern tree objc_lookup_ivar (tree, tree);
 968 extern void objc_clear_super_receiver (void);
 969 extern int objc_is_public (tree, tree);
 970 extern tree objc_is_id (tree);
 971 extern void objc_declare_alias (tree, tree);
 972 extern void objc_declare_class (tree);
 973 extern void objc_declare_protocols (tree);
 974 extern tree objc_build_message_expr (tree);
 975 extern tree objc_finish_message_expr (tree, tree, tree);
 976 extern tree objc_build_selector_expr (tree);
 977 extern tree objc_build_protocol_expr (tree);
 978 extern tree objc_build_encode_expr (tree);
 979 extern tree objc_build_string_object (tree);
 980 extern tree objc_get_protocol_qualified_type (tree, tree);
 981 extern tree objc_get_class_reference (tree);
 982 extern tree objc_get_class_ivars (tree);
 983 extern void objc_start_class_interface (tree, tree, tree);
 984 extern void objc_start_category_interface (tree, tree, tree);
 985 extern void objc_start_protocol (tree, tree);
 986 extern void objc_continue_interface (void);
 987 extern void objc_finish_interface (void);
 988 extern void objc_start_class_implementation (tree, tree);
 989 extern void objc_start_category_implementation (tree, tree);
 990 extern void objc_continue_implementation (void);
 991 extern void objc_finish_implementation (void);
 992 extern void objc_set_visibility (int);
 993 extern void objc_set_method_type (enum tree_code);
 994 extern tree objc_build_method_signature (tree, tree, tree, bool);
 995 extern void objc_add_method_declaration (tree);
 996 extern void objc_start_method_definition (tree);
 997 extern void objc_finish_method_definition (tree);
 998 extern void objc_add_instance_variable (tree);
 999 extern tree objc_build_keyword_decl (tree, tree, tree);
1000 extern tree objc_build_throw_stmt (tree);
1001 extern void objc_begin_try_stmt (location_t, tree);
1002 extern tree objc_finish_try_stmt (void);
1003 extern void objc_begin_catch_clause (tree);
1004 extern void objc_finish_catch_clause (void);
1005 extern void objc_build_finally_clause (location_t, tree);
1006 extern tree objc_build_synchronized (location_t, tree, tree);
1007 extern int objc_static_init_needed_p (void);
1008 extern tree objc_generate_static_init_call (tree);
1009 extern tree objc_generate_write_barrier (tree, enum tree_code, tree);
1010
1011 /* The following are provided by the C and C++ front-ends, and called by
1012    ObjC/ObjC++.  */
1013 extern void *objc_get_current_scope (void);
1014 extern void objc_mark_locals_volatile (void *);
1015
1016 /* In c-ppoutput.c  */
1017 extern void init_pp_output (FILE *);
1018 extern void preprocess_file (cpp_reader *);
1019 extern void pp_file_change (const struct line_map *);
1020 extern void pp_dir_change (cpp_reader *, const char *);
1021 extern bool check_missing_format_attribute (tree, tree);
1022
1023 /* In c-omp.c  */
1024 extern tree c_finish_omp_master (tree);
1025 extern tree c_finish_omp_critical (tree, tree);
1026 extern tree c_finish_omp_ordered (tree);
1027 extern void c_finish_omp_barrier (void);
1028 extern tree c_finish_omp_atomic (enum tree_code, tree, tree);
1029 extern void c_finish_omp_flush (void);
1030 extern void c_finish_omp_taskwait (void);
1031 extern tree c_finish_omp_for (location_t, tree, tree, tree, tree, tree, tree);
1032 extern void c_split_parallel_clauses (tree, tree *, tree *);
1033 extern enum omp_clause_default_kind c_omp_predetermined_sharing (tree);
1034
1035 /* Not in c-omp.c; provided by the front end.  */
1036 extern bool c_omp_sharing_predetermined (tree);
1037 extern tree c_omp_remap_decl (tree, bool);
1038
1039 /* In order for the format checking to accept the C frontend
1040    diagnostic framework extensions, you must include this file before
1041    toplev.h, not after.  The C front end formats are a subset of those
1042    for C++, so they are the appropriate set to use in common code;
1043    cp-tree.h overrides this for C++.  */
1044 #ifndef GCC_DIAG_STYLE
1045 #define GCC_DIAG_STYLE __gcc_cdiag__
1046 #endif
1047
1048 #endif /* ! GCC_C_COMMON_H */