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