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 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_COMMON_H
  23 #define GCC_C_COMMON_H
  24
  25 #include "splay-tree.h"
  26 #include "cpplib.h"
  27 #include "ggc.h"
  28
  29 /* Usage of TREE_LANG_FLAG_?:
  30    0: TREE_NEGATED_INT (in INTEGER_CST).
  31       IDENTIFIER_MARKED (used by search routines).
  32       DECL_PRETTY_FUNCTION_P (in VAR_DECL)
  33       STMT_EXPR_NO_SCOPE (in STMT_EXPR)
  34    1: C_DECLARED_LABEL_FLAG (in LABEL_DECL)
  35       STMT_IS_FULL_EXPR_P (in _STMT)
  36       STATEMENT_LIST_STMT_EXPR (in STATEMENT_LIST)
  37    2: unused
  38    3: unused
  39    4: unused
  40 */
  41
  42 /* Reserved identifiers.  This is the union of all the keywords for C,
  43    C++, and Objective-C.  All the type modifiers have to be in one
  44    block at the beginning, because they are used as mask bits.  There
  45    are 27 type modifiers; if we add many more we will have to redesign
  46    the mask mechanism.  */
  47
  48 enum rid
  49 {
  50   /* Modifiers: */
  51   /* C, in empirical order of frequency.  */
  52   RID_STATIC = 0,
  53   RID_UNSIGNED, RID_LONG,    RID_CONST, RID_EXTERN,
  54   RID_REGISTER, RID_TYPEDEF, RID_SHORT, RID_INLINE,
  55   RID_VOLATILE, RID_SIGNED,  RID_AUTO,  RID_RESTRICT,
  56
  57   /* C extensions */
  58   RID_COMPLEX, RID_THREAD,
  59
  60   /* C++ */
  61   RID_FRIEND, RID_VIRTUAL, RID_EXPLICIT, RID_EXPORT, RID_MUTABLE,
  62
  63   /* ObjC */
  64   RID_IN, RID_OUT, RID_INOUT, RID_BYCOPY, RID_BYREF, RID_ONEWAY,
  65
  66   /* C */
  67   RID_INT,     RID_CHAR,   RID_FLOAT,    RID_DOUBLE, RID_VOID,
  68   RID_ENUM,    RID_STRUCT, RID_UNION,    RID_IF,     RID_ELSE,
  69   RID_WHILE,   RID_DO,     RID_FOR,      RID_SWITCH, RID_CASE,
  70   RID_DEFAULT, RID_BREAK,  RID_CONTINUE, RID_RETURN, RID_GOTO,
  71   RID_SIZEOF,
  72
  73   /* C extensions */
  74   RID_ASM,       RID_TYPEOF,   RID_ALIGNOF,  RID_ATTRIBUTE,  RID_VA_ARG,
  75   RID_EXTENSION, RID_IMAGPART, RID_REALPART, RID_LABEL,      RID_PTRBASE,
  76   RID_PTREXTENT, RID_PTRVALUE, RID_CHOOSE_EXPR, RID_TYPES_COMPATIBLE_P,
  77
  78   /* Too many ways of getting the name of a function as a string */
  79   RID_FUNCTION_NAME, RID_PRETTY_FUNCTION_NAME, RID_C99_FUNCTION_NAME,
  80
  81   /* C++ */
  82   RID_BOOL,     RID_WCHAR,    RID_CLASS,
  83   RID_PUBLIC,   RID_PRIVATE,  RID_PROTECTED,
  84   RID_TEMPLATE, RID_NULL,     RID_CATCH,
  85   RID_DELETE,   RID_FALSE,    RID_NAMESPACE,
  86   RID_NEW,      RID_OFFSETOF, RID_OPERATOR,
  87   RID_THIS,     RID_THROW,    RID_TRUE,
  88   RID_TRY,      RID_TYPENAME, RID_TYPEID,
  89   RID_USING,
  90
  91   /* casts */
  92   RID_CONSTCAST, RID_DYNCAST, RID_REINTCAST, RID_STATCAST,
  93
  94   /* Objective-C */
  95   RID_ID,          RID_AT_ENCODE,    RID_AT_END,
  96   RID_AT_CLASS,    RID_AT_ALIAS,     RID_AT_DEFS,
  97   RID_AT_PRIVATE,  RID_AT_PROTECTED, RID_AT_PUBLIC,
  98   RID_AT_PROTOCOL, RID_AT_SELECTOR,
  99   RID_AT_THROW,    RID_AT_TRY,       RID_AT_CATCH,
 100   RID_AT_FINALLY,  RID_AT_SYNCHRONIZED,
 101   RID_AT_INTERFACE,
 102   RID_AT_IMPLEMENTATION,
 103
 104   RID_MAX,
 105
 106   RID_FIRST_MODIFIER = RID_STATIC,
 107   RID_LAST_MODIFIER = RID_ONEWAY,
 108
 109   RID_FIRST_AT = RID_AT_ENCODE,
 110   RID_LAST_AT = RID_AT_IMPLEMENTATION,
 111   RID_FIRST_PQ = RID_IN,
 112   RID_LAST_PQ = RID_ONEWAY
 113 };
 114
 115 #define OBJC_IS_AT_KEYWORD(rid) \
 116   ((unsigned int)(rid) >= (unsigned int)RID_FIRST_AT && \
 117    (unsigned int)(rid) <= (unsigned int)RID_LAST_AT)
 118
 119 #define OBJC_IS_PQ_KEYWORD(rid) \
 120   ((unsigned int)(rid) >= (unsigned int)RID_FIRST_PQ && \
 121    (unsigned int)(rid) <= (unsigned int)RID_LAST_PQ)
 122
 123 /* The elements of `ridpointers' are identifier nodes for the reserved
 124    type names and storage classes.  It is indexed by a RID_... value.  */
 125 extern GTY ((length ("(int)RID_MAX"))) tree *ridpointers;
 126
 127 /* Standard named or nameless data types of the C compiler.  */
 128
 129 enum c_tree_index
 130 {
 131     CTI_WCHAR_TYPE,
 132     CTI_SIGNED_WCHAR_TYPE,
 133     CTI_UNSIGNED_WCHAR_TYPE,
 134     CTI_WINT_TYPE,
 135     CTI_SIGNED_SIZE_TYPE, /* For format checking only.  */
 136     CTI_UNSIGNED_PTRDIFF_TYPE, /* For format checking only.  */
 137     CTI_INTMAX_TYPE,
 138     CTI_UINTMAX_TYPE,
 139     CTI_WIDEST_INT_LIT_TYPE,
 140     CTI_WIDEST_UINT_LIT_TYPE,
 141
 142     CTI_CHAR_ARRAY_TYPE,
 143     CTI_WCHAR_ARRAY_TYPE,
 144     CTI_INT_ARRAY_TYPE,
 145     CTI_STRING_TYPE,
 146     CTI_CONST_STRING_TYPE,
 147
 148     /* Type for boolean expressions (bool in C++, int in C).  */
 149     CTI_TRUTHVALUE_TYPE,
 150     CTI_TRUTHVALUE_TRUE,
 151     CTI_TRUTHVALUE_FALSE,
 152
 153     CTI_DEFAULT_FUNCTION_TYPE,
 154
 155     /* These are not types, but we have to look them up all the time.  */
 156     CTI_FUNCTION_NAME_DECL,
 157     CTI_PRETTY_FUNCTION_NAME_DECL,
 158     CTI_C99_FUNCTION_NAME_DECL,
 159     CTI_SAVED_FUNCTION_NAME_DECLS,
 160
 161     CTI_VOID_ZERO,
 162
 163     CTI_MAX
 164 };
 165
 166 #define C_RID_CODE(id)  (((struct c_common_identifier *) (id))->node.rid_code)
 167
 168 /* Identifier part common to the C front ends.  Inherits from
 169    tree_identifier, despite appearances.  */
 170 struct c_common_identifier GTY(())
 171 {
 172   struct tree_common common;
 173   struct cpp_hashnode node;
 174 };
 175
 176 #define wchar_type_node                 c_global_trees[CTI_WCHAR_TYPE]
 177 #define signed_wchar_type_node          c_global_trees[CTI_SIGNED_WCHAR_TYPE]
 178 #define unsigned_wchar_type_node        c_global_trees[CTI_UNSIGNED_WCHAR_TYPE]
 179 #define wint_type_node                  c_global_trees[CTI_WINT_TYPE]
 180 #define signed_size_type_node           c_global_trees[CTI_SIGNED_SIZE_TYPE]
 181 #define unsigned_ptrdiff_type_node      c_global_trees[CTI_UNSIGNED_PTRDIFF_TYPE]
 182 #define intmax_type_node                c_global_trees[CTI_INTMAX_TYPE]
 183 #define uintmax_type_node               c_global_trees[CTI_UINTMAX_TYPE]
 184 #define widest_integer_literal_type_node c_global_trees[CTI_WIDEST_INT_LIT_TYPE]
 185 #define widest_unsigned_literal_type_node c_global_trees[CTI_WIDEST_UINT_LIT_TYPE]
 186
 187 #define truthvalue_type_node            c_global_trees[CTI_TRUTHVALUE_TYPE]
 188 #define truthvalue_true_node            c_global_trees[CTI_TRUTHVALUE_TRUE]
 189 #define truthvalue_false_node           c_global_trees[CTI_TRUTHVALUE_FALSE]
 190
 191 #define char_array_type_node            c_global_trees[CTI_CHAR_ARRAY_TYPE]
 192 #define wchar_array_type_node           c_global_trees[CTI_WCHAR_ARRAY_TYPE]
 193 #define int_array_type_node             c_global_trees[CTI_INT_ARRAY_TYPE]
 194 #define string_type_node                c_global_trees[CTI_STRING_TYPE]
 195 #define const_string_type_node          c_global_trees[CTI_CONST_STRING_TYPE]
 196
 197 #define default_function_type           c_global_trees[CTI_DEFAULT_FUNCTION_TYPE]
 198
 199 #define function_name_decl_node         c_global_trees[CTI_FUNCTION_NAME_DECL]
 200 #define pretty_function_name_decl_node  c_global_trees[CTI_PRETTY_FUNCTION_NAME_DECL]
 201 #define c99_function_name_decl_node             c_global_trees[CTI_C99_FUNCTION_NAME_DECL]
 202 #define saved_function_name_decls       c_global_trees[CTI_SAVED_FUNCTION_NAME_DECLS]
 203
 204 /* A node for `((void) 0)'.  */
 205 #define void_zero_node                  c_global_trees[CTI_VOID_ZERO]
 206
 207 extern GTY(()) tree c_global_trees[CTI_MAX];
 208
 209 /* In a RECORD_TYPE, a sorted array of the fields of the type, not a
 210    tree for size reasons.  */
 211 struct sorted_fields_type GTY(())
 212 {
 213   int len;
 214   tree GTY((length ("%h.len"))) elts[1];
 215 };
 216
 217 /* Mark which labels are explicitly declared.
 218    These may be shadowed, and may be referenced from nested functions.  */
 219 #define C_DECLARED_LABEL_FLAG(label) TREE_LANG_FLAG_1 (label)
 220
 221 /* Flag strings given by __FUNCTION__ and __PRETTY_FUNCTION__ for a
 222    warning if they undergo concatenation.  */
 223 #define C_ARTIFICIAL_STRING_P(NODE) TREE_LANG_FLAG_0 (NODE)
 224
 225 typedef enum c_language_kind
 226 {
 227   clk_c         = 0,            /* C90, C94 or C99 */
 228   clk_objc      = 1,            /* clk_c with ObjC features.  */
 229   clk_cxx       = 2,            /* ANSI/ISO C++ */
 230   clk_objcxx    = 3             /* clk_cxx with ObjC features.  */
 231 }
 232 c_language_kind;
 233
 234 /* To test for a specific language use c_language, defined by each
 235    front end.  For "ObjC features" or "not C++" use the macros.  */
 236 extern c_language_kind c_language;
 237
 238 #define c_dialect_cxx()         (c_language & clk_cxx)
 239 #define c_dialect_objc()        (c_language & clk_objc)
 240
 241 /* Information about a statement tree.  */
 242
 243 struct stmt_tree_s GTY(()) {
 244   /* The current statment list being collected.  */
 245   tree x_cur_stmt_list;
 246
 247   /* In C++, Nonzero if we should treat statements as full
 248      expressions.  In particular, this variable is no-zero if at the
 249      end of a statement we should destroy any temporaries created
 250      during that statement.  Similarly, if, at the end of a block, we
 251      should destroy any local variables in this block.  Normally, this
 252      variable is nonzero, since those are the normal semantics of
 253      C++.
 254
 255      However, in order to represent aggregate initialization code as
 256      tree structure, we use statement-expressions.  The statements
 257      within the statement expression should not result in cleanups
 258      being run until the entire enclosing statement is complete.
 259
 260      This flag has no effect in C.  */
 261   int stmts_are_full_exprs_p;
 262 };
 263
 264 typedef struct stmt_tree_s *stmt_tree;
 265
 266 /* Global state pertinent to the current function.  Some C dialects
 267    extend this structure with additional fields.  */
 268
 269 struct c_language_function GTY(()) {
 270   /* While we are parsing the function, this contains information
 271      about the statement-tree that we are building.  */
 272   struct stmt_tree_s x_stmt_tree;
 273 };
 274
 275 /* When building a statement-tree, this is the current statment list
 276    being collected.  It's TREE_CHAIN is a back-pointer to the previous
 277    statment list.  */
 278
 279 #define cur_stmt_list (current_stmt_tree ()->x_cur_stmt_list)
 280
 281 /* Language-specific hooks.  */
 282
 283 extern void (*lang_expand_function_end) (void);
 284
 285 /* Callback that determines if it's ok for a function to have no
 286    noreturn attribute.  */
 287 extern int (*lang_missing_noreturn_ok_p) (tree);
 288
 289 extern void push_file_scope (void);
 290 extern void pop_file_scope (void);
 291 extern int yyparse (void);
 292 extern stmt_tree current_stmt_tree (void);
 293 extern tree push_stmt_list (void);
 294 extern tree re_push_stmt_list (tree);
 295 extern tree pop_stmt_list (tree);
 296 extern tree add_stmt (tree);
 297 extern void push_cleanup (tree, tree, bool);
 298
 299 extern tree walk_stmt_tree (tree *, walk_tree_fn, void *);
 300 extern int c_expand_decl (tree);
 301
 302 extern int field_decl_cmp (const void *, const void *);
 303 extern void resort_sorted_fields (void *, void *, gt_pointer_operator,
 304                                   void *);
 305 extern bool has_c_linkage (tree decl);
 306 \f
 307 /* Switches common to the C front ends.  */
 308
 309 /* Nonzero if prepreprocessing only.  */
 310
 311 extern int flag_preprocess_only;
 312
 313 /* Zero means that faster, ...NonNil variants of objc_msgSend...
 314    calls will be used in ObjC; passing nil receivers to such calls
 315    will most likely result in crashes.  */
 316 extern int flag_nil_receivers;
 317
 318 /* Nonzero means that we will allow new ObjC exception syntax (@throw,
 319    @try, etc.) in source code.  */
 320 extern int flag_objc_exceptions;
 321
 322 /* Nonzero means that we generate NeXT setjmp based exceptions.  */
 323 extern int flag_objc_sjlj_exceptions;
 324
 325 /* Nonzero means that code generation will be altered to support
 326    "zero-link" execution.  This currently affects ObjC only, but may
 327    affect other languages in the future.  */
 328 extern int flag_zero_link;
 329
 330 /* Nonzero means emit an '__OBJC, __image_info' for the current translation
 331    unit.  It will inform the ObjC runtime that class definition(s) herein
 332    contained are to replace one(s) previously loaded.  */
 333 extern int flag_replace_objc_classes;
 334
 335 /* Nonzero means don't output line number information.  */
 336
 337 extern char flag_no_line_commands;
 338
 339 /* Nonzero causes -E output not to be done, but directives such as
 340    #define that have side effects are still obeyed.  */
 341
 342 extern char flag_no_output;
 343
 344 /* Nonzero means dump macros in some fashion; contains the 'D', 'M' or
 345    'N' of the command line switch.  */
 346
 347 extern char flag_dump_macros;
 348
 349 /* Nonzero means pass #include lines through to the output.  */
 350
 351 extern char flag_dump_includes;
 352
 353 /* The file name to which we should write a precompiled header, or
 354    NULL if no header will be written in this compile.  */
 355
 356 extern const char *pch_file;
 357
 358 /* Nonzero if an ISO standard was selected.  It rejects macros in the
 359    user's namespace.  */
 360
 361 extern int flag_iso;
 362
 363 /* Nonzero if -undef was given.  It suppresses target built-in macros
 364    and assertions.  */
 365
 366 extern int flag_undef;
 367
 368 /* Nonzero means don't recognize the non-ANSI builtin functions.  */
 369
 370 extern int flag_no_builtin;
 371
 372 /* Nonzero means don't recognize the non-ANSI builtin functions.
 373    -ansi sets this.  */
 374
 375 extern int flag_no_nonansi_builtin;
 376
 377 /* Nonzero means give `double' the same size as `float'.  */
 378
 379 extern int flag_short_double;
 380
 381 /* Nonzero means give `wchar_t' the same size as `short'.  */
 382
 383 extern int flag_short_wchar;
 384
 385 /* Nonzero means allow Microsoft extensions without warnings or errors.  */
 386 extern int flag_ms_extensions;
 387
 388 /* Nonzero means don't recognize the keyword `asm'.  */
 389
 390 extern int flag_no_asm;
 391
 392 /* Nonzero means give string constants the type `const char *', as mandated
 393    by the standard.  */
 394
 395 extern int flag_const_strings;
 396
 397 /* Nonzero means to treat bitfields as signed unless they say `unsigned'.  */
 398
 399 extern int flag_signed_bitfields;
 400 extern int explicit_flag_signed_bitfields;
 401
 402 /* Nonzero means warn about pointer casts that can drop a type qualifier
 403    from the pointer target type.  */
 404
 405 extern int warn_cast_qual;
 406
 407 /* Warn about functions which might be candidates for format attributes.  */
 408
 409 extern int warn_missing_format_attribute;
 410
 411 /* Nonzero means warn about sizeof(function) or addition/subtraction
 412    of function pointers.  */
 413
 414 extern int warn_pointer_arith;
 415
 416 /* Nonzero means warn for any global function def
 417    without separate previous prototype decl.  */
 418
 419 extern int warn_missing_prototypes;
 420
 421 /* Warn if adding () is suggested.  */
 422
 423 extern int warn_parentheses;
 424
 425 /* Warn if initializer is not completely bracketed.  */
 426
 427 extern int warn_missing_braces;
 428
 429 /* Warn about comparison of signed and unsigned values.
 430    If -1, neither -Wsign-compare nor -Wno-sign-compare has been specified.  */
 431
 432 extern int warn_sign_compare;
 433
 434 /* Nonzero means warn about usage of long long when `-pedantic'.  */
 435
 436 extern int warn_long_long;
 437
 438 /* Nonzero means warn about deprecated conversion from string constant to
 439    `char *'.  */
 440
 441 extern int warn_write_strings;
 442
 443 /* Nonzero means warn about multiple (redundant) decls for the same single
 444    variable or function.  */
 445
 446 extern int warn_redundant_decls;
 447
 448 /* Warn about testing equality of floating point numbers.  */
 449
 450 extern int warn_float_equal;
 451
 452 /* Warn about a subscript that has type char.  */
 453
 454 extern int warn_char_subscripts;
 455
 456 /* Warn if a type conversion is done that might have confusing results.  */
 457
 458 extern int warn_conversion;
 459
 460 /* Warn about #pragma directives that are not recognized.  */
 461
 462 extern int warn_unknown_pragmas; /* Tri state variable.  */
 463
 464 /* Warn about format/argument anomalies in calls to formatted I/O functions
 465    (*printf, *scanf, strftime, strfmon, etc.).  */
 466
 467 extern int warn_format;
 468
 469 /* Warn about Y2K problems with strftime formats.  */
 470
 471 extern int warn_format_y2k;
 472
 473 /* Warn about excess arguments to formats.  */
 474
 475 extern int warn_format_extra_args;
 476
 477 /* Warn about zero-length formats.  */
 478
 479 extern int warn_format_zero_length;
 480
 481 /* Warn about non-literal format arguments.  */
 482
 483 extern int warn_format_nonliteral;
 484
 485 /* Warn about possible security problems with calls to format functions.  */
 486
 487 extern int warn_format_security;
 488
 489
 490 /* C/ObjC language option variables.  */
 491
 492
 493 /* Nonzero means message about use of implicit function declarations;
 494  1 means warning; 2 means error.  */
 495
 496 extern int mesg_implicit_function_declaration;
 497
 498 /* Nonzero means allow type mismatches in conditional expressions;
 499    just make their values `void'.  */
 500
 501 extern int flag_cond_mismatch;
 502
 503 /* Nonzero means enable C89 Amendment 1 features.  */
 504
 505 extern int flag_isoc94;
 506
 507 /* Nonzero means use the ISO C99 dialect of C.  */
 508
 509 extern int flag_isoc99;
 510
 511 /* Nonzero means that we have builtin functions, and main is an int.  */
 512
 513 extern int flag_hosted;
 514
 515 /* Nonzero means warn when casting a function call to a type that does
 516    not match the return type (e.g. (float)sqrt() or (anything*)malloc()
 517    when there is no previous declaration of sqrt or malloc.  */
 518
 519 extern int warn_bad_function_cast;
 520
 521 /* Warn about traditional constructs whose meanings changed in ANSI C.  */
 522
 523 extern int warn_traditional;
 524
 525 /* Nonzero means warn for a declaration found after a statement.  */
 526
 527 extern int warn_declaration_after_statement;
 528
 529 /* Nonzero means warn for non-prototype function decls
 530    or non-prototyped defs without previous prototype.  */
 531
 532 extern int warn_strict_prototypes;
 533
 534 /* Nonzero means warn for any global function def
 535    without separate previous decl.  */
 536
 537 extern int warn_missing_declarations;
 538
 539 /* Nonzero means warn about extern declarations of objects not at
 540    file-scope level and about *all* declarations of functions (whether
 541    extern or static) not at file-scope level.  Note that we exclude
 542    implicit function declarations.  To get warnings about those, use
 543    -Wimplicit.  */
 544
 545 extern int warn_nested_externs;
 546
 547 /* Warn if main is suspicious.  */
 548
 549 extern int warn_main;
 550
 551 /* Nonzero means warn about possible violations of sequence point rules.  */
 552
 553 extern int warn_sequence_point;
 554
 555 /* Nonzero means warn about uninitialized variable when it is initialized with itself.
 556    For example: int i = i;, GCC will not warn about this when warn_init_self is nonzero.  */
 557
 558 extern int warn_init_self;
 559
 560
 561 /* Nonzero means to warn about compile-time division by zero.  */
 562 extern int warn_div_by_zero;
 563
 564 /* Nonzero means warn about use of implicit int.  */
 565
 566 extern int warn_implicit_int;
 567
 568 /* Warn about NULL being passed to argument slots marked as requiring
 569    non-NULL.  */
 570
 571 extern int warn_nonnull;
 572
 573 /* Warn about old-style parameter declaration.  */
 574
 575 extern int warn_old_style_definition;
 576
 577
 578 /* ObjC language option variables.  */
 579
 580
 581 /* Open and close the file for outputting class declarations, if
 582    requested (ObjC).  */
 583
 584 extern int flag_gen_declaration;
 585
 586 /* Generate code for GNU or NeXT runtime environment.  */
 587
 588 extern int flag_next_runtime;
 589
 590 /* Tells the compiler that this is a special run.  Do not perform any
 591    compiling, instead we are to test some platform dependent features
 592    and output a C header file with appropriate definitions.  */
 593
 594 extern int print_struct_values;
 595
 596 /* ???.  Undocumented.  */
 597
 598 extern const char *constant_string_class_name;
 599
 600 /* Warn if multiple methods are seen for the same selector, but with
 601    different argument types.  Performs the check on the whole selector
 602    table at the end of compilation.  */
 603
 604 extern int warn_selector;
 605
 606 /* Warn if a @selector() is found, and no method with that selector
 607    has been previously declared.  The check is done on each
 608    @selector() as soon as it is found - so it warns about forward
 609    declarations.  */
 610
 611 extern int warn_undeclared_selector;
 612
 613 /* Warn if methods required by a protocol are not implemented in the
 614    class adopting it.  When turned off, methods inherited to that
 615    class are also considered implemented.  */
 616
 617 extern int warn_protocol;
 618
 619
 620 /* C++ language option variables.  */
 621
 622
 623 /* Nonzero means don't recognize any extension keywords.  */
 624
 625 extern int flag_no_gnu_keywords;
 626
 627 /* Nonzero means do emit exported implementations of functions even if
 628    they can be inlined.  */
 629
 630 extern int flag_implement_inlines;
 631
 632 /* Nonzero means that implicit instantiations will be emitted if needed.  */
 633
 634 extern int flag_implicit_templates;
 635
 636 /* Nonzero means that implicit instantiations of inline templates will be
 637    emitted if needed, even if instantiations of non-inline templates
 638    aren't.  */
 639
 640 extern int flag_implicit_inline_templates;
 641
 642 /* Nonzero means generate separate instantiation control files and
 643    juggle them at link time.  */
 644
 645 extern int flag_use_repository;
 646
 647 /* Nonzero if we want to issue diagnostics that the standard says are not
 648    required.  */
 649
 650 extern int flag_optional_diags;
 651
 652 /* Nonzero means we should attempt to elide constructors when possible.  */
 653
 654 extern int flag_elide_constructors;
 655
 656 /* Nonzero means that member functions defined in class scope are
 657    inline by default.  */
 658
 659 extern int flag_default_inline;
 660
 661 /* Controls whether compiler generates 'type descriptor' that give
 662    run-time type information.  */
 663
 664 extern int flag_rtti;
 665
 666 /* Nonzero if we want to conserve space in the .o files.  We do this
 667    by putting uninitialized data and runtime initialized data into
 668    .common instead of .data at the expense of not flagging multiple
 669    definitions.  */
 670
 671 extern int flag_conserve_space;
 672
 673 /* Nonzero if we want to obey access control semantics.  */
 674
 675 extern int flag_access_control;
 676
 677 /* Nonzero if we want to check the return value of new and avoid calling
 678    constructors if it is a null pointer.  */
 679
 680 extern int flag_check_new;
 681
 682 /* Nonzero if we want the new ISO rules for pushing a new scope for `for'
 683    initialization variables.
 684    0: Old rules, set by -fno-for-scope.
 685    2: New ISO rules, set by -ffor-scope.
 686    1: Try to implement new ISO rules, but with backup compatibility
 687    (and warnings).  This is the default, for now.  */
 688
 689 extern int flag_new_for_scope;
 690
 691 /* Nonzero if we want to emit defined symbols with common-like linkage as
 692    weak symbols where possible, in order to conform to C++ semantics.
 693    Otherwise, emit them as local symbols.  */
 694
 695 extern int flag_weak;
 696
 697 /* 0 means we want the preprocessor to not emit line directives for
 698    the current working directory.  1 means we want it to do it.  -1
 699    means we should decide depending on whether debugging information
 700    is being emitted or not.  */
 701
 702 extern int flag_working_directory;
 703
 704 /* Nonzero to use __cxa_atexit, rather than atexit, to register
 705    destructors for local statics and global objects.  */
 706
 707 extern int flag_use_cxa_atexit;
 708
 709 /* Nonzero means make the default pedwarns warnings instead of errors.
 710    The value of this flag is ignored if -pedantic is specified.  */
 711
 712 extern int flag_permissive;
 713
 714 /* Nonzero means to implement standard semantics for exception
 715    specifications, calling unexpected if an exception is thrown that
 716    doesn't match the specification.  Zero means to treat them as
 717    assertions and optimize accordingly, but not check them.  */
 718
 719 extern int flag_enforce_eh_specs;
 720
 721 /* Nonzero means warn about things that will change when compiling
 722    with an ABI-compliant compiler.  */
 723
 724 extern int warn_abi;
 725
 726 /* Nonzero means warn about invalid uses of offsetof.  */
 727
 728 extern int warn_invalid_offsetof;
 729
 730 /* Nonzero means warn about implicit declarations.  */
 731
 732 extern int warn_implicit;
 733
 734 /* Nonzero means warn when all ctors or dtors are private, and the class
 735    has no friends.  */
 736
 737 extern int warn_ctor_dtor_privacy;
 738
 739 /* Nonzero means warn in function declared in derived class has the
 740    same name as a virtual in the base class, but fails to match the
 741    type signature of any virtual function in the base class.  */
 742
 743 extern int warn_overloaded_virtual;
 744
 745 /* Nonzero means warn when declaring a class that has a non virtual
 746    destructor, when it really ought to have a virtual one.  */
 747
 748 extern int warn_nonvdtor;
 749
 750 /* Nonzero means warn when the compiler will reorder code.  */
 751
 752 extern int warn_reorder;
 753
 754 /* Nonzero means warn when synthesis behavior differs from Cfront's.  */
 755
 756 extern int warn_synth;
 757
 758 /* Nonzero means warn when we convert a pointer to member function
 759    into a pointer to (void or function).  */
 760
 761 extern int warn_pmf2ptr;
 762
 763 /* Nonzero means warn about violation of some Effective C++ style rules.  */
 764
 765 extern int warn_ecpp;
 766
 767 /* Nonzero means warn where overload resolution chooses a promotion from
 768    unsigned to signed over a conversion to an unsigned of the same size.  */
 769
 770 extern int warn_sign_promo;
 771
 772 /* Nonzero means warn when an old-style cast is used.  */
 773
 774 extern int warn_old_style_cast;
 775
 776 /* Nonzero means warn when non-templatized friend functions are
 777    declared within a template */
 778
 779 extern int warn_nontemplate_friend;
 780
 781 /* Nonzero means complain about deprecated features.  */
 782
 783 extern int warn_deprecated;
 784
 785 /* Maximum template instantiation depth.  This limit is rather
 786    arbitrary, but it exists to limit the time it takes to notice
 787    infinite template instantiations.  */
 788
 789 extern int max_tinst_depth;
 790
 791 /* Nonzero means the expression being parsed will never be evaluated.
 792    This is a count, since unevaluated expressions can nest.  */
 793
 794 extern int skip_evaluation;
 795
 796 /* C types are partitioned into three subsets: object, function, and
 797    incomplete types.  */
 798 #define C_TYPE_OBJECT_P(type) \
 799   (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type))
 800
 801 #define C_TYPE_INCOMPLETE_P(type) \
 802   (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type) == 0)
 803
 804 #define C_TYPE_FUNCTION_P(type) \
 805   (TREE_CODE (type) == FUNCTION_TYPE)
 806
 807 /* For convenience we define a single macro to identify the class of
 808    object or incomplete types.  */
 809 #define C_TYPE_OBJECT_OR_INCOMPLETE_P(type) \
 810   (!C_TYPE_FUNCTION_P (type))
 811
 812 /* Record in each node resulting from a binary operator
 813    what operator was specified for it.  */
 814 #define C_EXP_ORIGINAL_CODE(exp) ((enum tree_code) TREE_COMPLEXITY (exp))
 815
 816 /* Attribute table common to the C front ends.  */
 817 extern const struct attribute_spec c_common_attribute_table[];
 818 extern const struct attribute_spec c_common_format_attribute_table[];
 819
 820 /* Pointer to function to lazily generate the VAR_DECL for __FUNCTION__ etc.
 821    ID is the identifier to use, NAME is the string.
 822    TYPE_DEP indicates whether it depends on type of the function or not
 823    (i.e. __PRETTY_FUNCTION__).  */
 824
 825 extern tree (*make_fname_decl) (tree, int);
 826
 827 extern tree identifier_global_value (tree);
 828 extern void record_builtin_type (enum rid, const char *, tree);
 829 extern tree build_void_list_node (void);
 830 extern void start_fname_decls (void);
 831 extern void finish_fname_decls (void);
 832 extern const char *fname_as_string (int);
 833 extern tree fname_decl (unsigned, tree);
 834
 835 extern void check_function_arguments (tree, tree);
 836 extern void check_function_arguments_recurse (void (*)
 837                                               (void *, tree,
 838                                                unsigned HOST_WIDE_INT),
 839                                               void *, tree,
 840                                               unsigned HOST_WIDE_INT);
 841 extern void check_function_format (int *, tree, tree);
 842 extern void set_Wformat (int);
 843 extern tree handle_format_attribute (tree *, tree, tree, int, bool *);
 844 extern tree handle_format_arg_attribute (tree *, tree, tree, int, bool *);
 845 extern int c_common_handle_option (size_t code, const char *arg, int value);
 846 extern bool c_common_missing_argument (const char *opt, size_t code);
 847 extern tree c_common_type_for_mode (enum machine_mode, int);
 848 extern tree c_common_type_for_size (unsigned int, int);
 849 extern tree c_common_unsigned_type (tree);
 850 extern tree c_common_signed_type (tree);
 851 extern tree c_common_signed_or_unsigned_type (int, tree);
 852 extern tree c_common_truthvalue_conversion (tree);
 853 extern void c_apply_type_quals_to_decl (int, tree);
 854 extern tree c_sizeof_or_alignof_type (tree, enum tree_code, int);
 855 extern tree c_alignof_expr (tree);
 856 /* Print an error message for invalid operands to arith operation CODE.
 857    NOP_EXPR is used as a special case (see truthvalue_conversion).  */
 858 extern void binary_op_error (enum tree_code);
 859 #define my_friendly_assert(EXP, N) (void) \
 860  (((EXP) == 0) ? (fancy_abort (__FILE__, __LINE__, __FUNCTION__), 0) : 0)
 861
 862 /* Validate the expression after `case' and apply default promotions.  */
 863 extern tree check_case_value (tree);
 864 extern tree fix_string_type (tree);
 865 struct varray_head_tag;
 866 extern void constant_expression_warning (tree);
 867 extern tree convert_and_check (tree, tree);
 868 extern void overflow_warning (tree);
 869 extern void unsigned_conversion_warning (tree, tree);
 870
 871 #define c_sizeof(T)  c_sizeof_or_alignof_type (T, SIZEOF_EXPR, 1)
 872 #define c_alignof(T) c_sizeof_or_alignof_type (T, ALIGNOF_EXPR, 1)
 873
 874 /* Subroutine of build_binary_op, used for comparison operations.
 875    See if the operands have both been converted from subword integer types
 876    and, if so, perhaps change them both back to their original type.  */
 877 extern tree shorten_compare (tree *, tree *, tree *, enum tree_code *);
 878
 879 extern tree pointer_int_sum (enum tree_code, tree, tree);
 880 extern unsigned int min_precision (tree, int);
 881
 882 /* Add qualifiers to a type, in the fashion for C.  */
 883 extern tree c_build_qualified_type (tree, int);
 884
 885 /* Build tree nodes and builtin functions common to both C and C++ language
 886    frontends.  */
 887 extern void c_common_nodes_and_builtins (void);
 888
 889 extern void disable_builtin_function (const char *);
 890
 891 extern tree build_va_arg (tree, tree);
 892
 893 extern unsigned int c_common_init_options (unsigned int, const char **);
 894 extern bool c_common_post_options (const char **);
 895 extern bool c_common_init (void);
 896 extern void c_common_finish (void);
 897 extern void c_common_parse_file (int);
 898 extern HOST_WIDE_INT c_common_get_alias_set (tree);
 899 extern void c_register_builtin_type (tree, const char*);
 900 extern bool c_promoting_integer_type_p (tree);
 901 extern int self_promoting_args_p (tree);
 902 extern tree strip_array_types (tree);
 903 extern tree strip_pointer_operator (tree);
 904
 905 /* This is the basic parsing function.  */
 906 extern void c_parse_file (void);
 907 /* This is misnamed, it actually performs end-of-compilation processing.  */
 908 extern void finish_file (void);
 909
 910 /* These macros provide convenient access to the various _STMT nodes.  */
 911
 912 /* Nonzero if this statement should be considered a full-expression,
 913    i.e., if temporaries created during this statement should have
 914    their destructors run at the end of this statement.  (In C, this
 915    will always be false, since there are no destructors.)  */
 916 #define STMT_IS_FULL_EXPR_P(NODE) TREE_LANG_FLAG_1 ((NODE))
 917
 918 /* Nonzero if a given STATEMENT_LIST represents the outermost binding
 919    if a statement expression.  */
 920 #define STATEMENT_LIST_STMT_EXPR(NODE) \
 921   TREE_LANG_FLAG_1 (STATEMENT_LIST_CHECK (NODE))
 922
 923 /* WHILE_STMT accessors. These give access to the condition of the
 924    while statement and the body of the while statement, respectively.  */
 925 #define WHILE_COND(NODE)        TREE_OPERAND (WHILE_STMT_CHECK (NODE), 0)
 926 #define WHILE_BODY(NODE)        TREE_OPERAND (WHILE_STMT_CHECK (NODE), 1)
 927
 928 /* DO_STMT accessors. These give access to the condition of the do
 929    statement and the body of the do statement, respectively.  */
 930 #define DO_COND(NODE)           TREE_OPERAND (DO_STMT_CHECK (NODE), 0)
 931 #define DO_BODY(NODE)           TREE_OPERAND (DO_STMT_CHECK (NODE), 1)
 932
 933 /* RETURN_STMT accessors. These give the expression associated with a
 934    return statement, and whether it should be ignored when expanding
 935    (as opposed to inlining).  */
 936 #define RETURN_STMT_EXPR(NODE)  TREE_OPERAND (RETURN_STMT_CHECK (NODE), 0)
 937
 938 /* EXPR_STMT accessor. This gives the expression associated with an
 939    expression statement.  */
 940 #define EXPR_STMT_EXPR(NODE)    TREE_OPERAND (EXPR_STMT_CHECK (NODE), 0)
 941
 942 /* FOR_STMT accessors. These give access to the init statement,
 943    condition, update expression, and body of the for statement,
 944    respectively.  */
 945 #define FOR_INIT_STMT(NODE)     TREE_OPERAND (FOR_STMT_CHECK (NODE), 0)
 946 #define FOR_COND(NODE)          TREE_OPERAND (FOR_STMT_CHECK (NODE), 1)
 947 #define FOR_EXPR(NODE)          TREE_OPERAND (FOR_STMT_CHECK (NODE), 2)
 948 #define FOR_BODY(NODE)          TREE_OPERAND (FOR_STMT_CHECK (NODE), 3)
 949
 950 #define SWITCH_TYPE(NODE)       TREE_OPERAND (SWITCH_STMT_CHECK (NODE), 2)
 951
 952 /* DECL_STMT accessor. This gives access to the DECL associated with
 953    the given declaration statement.  */
 954 #define DECL_STMT_DECL(NODE)    TREE_OPERAND (DECL_STMT_CHECK (NODE), 0)
 955
 956 /* STMT_EXPR accessor.  */
 957 #define STMT_EXPR_STMT(NODE)    TREE_OPERAND (STMT_EXPR_CHECK (NODE), 0)
 958
 959 /* Nonzero if this statement-expression does not have an associated scope.  */
 960 #define STMT_EXPR_NO_SCOPE(NODE) \
 961    TREE_LANG_FLAG_0 (STMT_EXPR_CHECK (NODE))
 962
 963 /* COMPOUND_LITERAL_EXPR accessors.  */
 964 #define COMPOUND_LITERAL_EXPR_DECL_STMT(NODE)           \
 965   TREE_OPERAND (COMPOUND_LITERAL_EXPR_CHECK (NODE), 0)
 966 #define COMPOUND_LITERAL_EXPR_DECL(NODE)                        \
 967   DECL_STMT_DECL (COMPOUND_LITERAL_EXPR_DECL_STMT (NODE))
 968
 969 #define DEFTREECODE(SYM, NAME, TYPE, LENGTH) SYM,
 970
 971 enum c_tree_code {
 972   C_DUMMY_TREE_CODE = LAST_AND_UNUSED_TREE_CODE,
 973 #include "c-common.def"
 974   LAST_C_TREE_CODE
 975 };
 976
 977 #undef DEFTREECODE
 978
 979 #define c_common_stmt_codes                             \
 980    EXPR_STMT,           DECL_STMT,      FOR_STMT,       \
 981    WHILE_STMT,          DO_STMT,        RETURN_STMT,    \
 982    BREAK_STMT,          CONTINUE_STMT,  SWITCH_STMT
 983
 984 /* TRUE if a code represents a statement.  The front end init
 985    langhook should take care of initialization of this array.  */
 986 extern bool statement_code_p[MAX_TREE_CODES];
 987
 988 #define STATEMENT_CODE_P(CODE) statement_code_p[(int) (CODE)]
 989
 990 #define INIT_STATEMENT_CODES(STMT_CODES)                        \
 991   do {                                                          \
 992     unsigned int i;                                             \
 993     memset (&statement_code_p, 0, sizeof (statement_code_p));   \
 994     for (i = 0; i < ARRAY_SIZE (STMT_CODES); i++)               \
 995       statement_code_p[STMT_CODES[i]] = true;                   \
 996   } while (0)
 997
 998 extern int stmts_are_full_exprs_p (void);
 999 extern int anon_aggr_type_p (tree);
1000
1001 /* For a VAR_DECL that is an anonymous union, these are the various
1002    sub-variables that make up the anonymous union.  */
1003 #define DECL_ANON_UNION_ELEMS(NODE) DECL_ARGUMENTS ((NODE))
1004
1005 /* In a FIELD_DECL, nonzero if the decl was originally a bitfield.  */
1006 #define DECL_C_BIT_FIELD(NODE) \
1007   (DECL_LANG_FLAG_4 (FIELD_DECL_CHECK (NODE)) == 1)
1008 #define SET_DECL_C_BIT_FIELD(NODE) \
1009   (DECL_LANG_FLAG_4 (FIELD_DECL_CHECK (NODE)) = 1)
1010 #define CLEAR_DECL_C_BIT_FIELD(NODE) \
1011   (DECL_LANG_FLAG_4 (FIELD_DECL_CHECK (NODE)) = 0)
1012
1013 extern void emit_local_var (tree);
1014 extern void make_rtl_for_local_static (tree);
1015 extern tree c_expand_return (tree);
1016 extern tree do_case (tree, tree);
1017 extern tree build_stmt (enum tree_code, ...);
1018 extern tree build_case_label (tree, tree, tree);
1019 extern tree build_continue_stmt (void);
1020 extern tree build_break_stmt (void);
1021 extern tree build_return_stmt (tree);
1022
1023 extern void c_expand_asm_operands (tree, tree, tree, tree, int, location_t);
1024
1025 /* These functions must be defined by each front-end which implements
1026    a variant of the C language.  They are used in c-common.c.  */
1027
1028 extern tree build_unary_op (enum tree_code, tree, int);
1029 extern tree build_binary_op (enum tree_code, tree, tree, int);
1030 extern int lvalue_p (tree);
1031 extern tree default_conversion (tree);
1032
1033 /* Given two integer or real types, return the type for their sum.
1034    Given two compatible ANSI C types, returns the merged type.  */
1035
1036 extern tree common_type (tree, tree);
1037
1038 extern tree expand_tree_builtin (tree, tree, tree);
1039
1040 extern tree decl_constant_value (tree);
1041
1042 /* Handle increment and decrement of boolean types.  */
1043 extern tree boolean_increment (enum tree_code, tree);
1044
1045 /* Hook currently used only by the C++ front end to reset internal state
1046    after entering or leaving a header file.  */
1047 extern void extract_interface_info (void);
1048
1049 extern int case_compare (splay_tree_key, splay_tree_key);
1050
1051 extern tree c_add_case_label (splay_tree, tree, tree, tree);
1052
1053 extern void c_do_switch_warnings (splay_tree, tree);
1054
1055 extern tree build_function_call (tree, tree);
1056
1057 extern tree finish_label_address_expr (tree);
1058
1059 /* Same function prototype, but the C and C++ front ends have
1060    different implementations.  Used in c-common.c.  */
1061 extern tree lookup_label (tree);
1062
1063 extern int vector_types_convertible_p (tree t1, tree t2);
1064
1065 extern rtx c_expand_expr (tree, rtx, enum machine_mode, int, rtx *);
1066
1067 extern int c_safe_from_p (rtx, tree);
1068
1069 extern int c_staticp (tree);
1070
1071 extern int c_common_unsafe_for_reeval (tree);
1072
1073 extern void init_c_lex (void);
1074
1075 extern void c_cpp_builtins (cpp_reader *);
1076
1077 /* Positive if an implicit `extern "C"' scope has just been entered;
1078    negative if such a scope has just been exited.  */
1079 extern GTY(()) int pending_lang_change;
1080
1081 /* Information recorded about each file examined during compilation.  */
1082
1083 struct c_fileinfo
1084 {
1085   int time;     /* Time spent in the file.  */
1086   short interface_only;         /* Flags - used only by C++ */
1087   short interface_unknown;
1088 };
1089
1090 struct c_fileinfo *get_fileinfo (const char *);
1091 extern void dump_time_statistics (void);
1092
1093 extern bool c_dump_tree (void *, tree);
1094
1095 extern tree c_walk_subtrees (tree*, int*, walk_tree_fn, void*, void*);
1096
1097 extern void c_warn_unused_result (tree *);
1098
1099 extern void verify_sequence_points (tree);
1100
1101 /* In c-gimplify.c  */
1102 extern void c_genericize (tree);
1103 extern int c_gimplify_expr (tree *, tree *, tree *);
1104 extern tree c_build_bind_expr (tree, tree);
1105
1106 extern void pch_init (void);
1107 extern int c_common_valid_pch (cpp_reader *pfile, const char *name, int fd);
1108 extern void c_common_read_pch (cpp_reader *pfile, const char *name, int fd,
1109                                const char *orig);
1110 extern void c_common_write_pch (void);
1111 extern void c_common_no_more_pch (void);
1112 extern void builtin_define_with_value (const char *, const char *, int);
1113 extern void c_stddef_cpp_builtins (void);
1114 extern void fe_file_change (const struct line_map *);
1115 extern void c_parse_error (const char *, enum cpp_ttype, tree);
1116
1117 /* The following have been moved here from c-tree.h, since they're needed
1118    in the ObjC++ world, too.  What is more, stub-objc.c could use a few
1119    prototypes.  */
1120 extern tree lookup_interface (tree);
1121 extern tree is_class_name (tree);
1122 extern tree objc_is_object_ptr (tree);
1123 extern void objc_check_decl (tree);
1124 extern int objc_comptypes (tree, tree, int);
1125 extern tree objc_message_selector (void);
1126 extern tree lookup_objc_ivar (tree);
1127 extern void *get_current_scope (void);
1128 extern void objc_mark_locals_volatile (void *);
1129 extern void objc_clear_super_receiver (void);
1130 extern int objc_is_public (tree, tree);
1131
1132 /* In c-ppoutput.c  */
1133 extern void init_pp_output (FILE *);
1134 extern void preprocess_file (cpp_reader *);
1135 extern void pp_file_change (const struct line_map *);
1136 extern void pp_dir_change (cpp_reader *, const char *);
1137
1138 #endif /* ! GCC_C_COMMON_H */