gcc/c-tree.h

   1 /* Definitions for C parsing and type checking.
   2    Copyright (C) 1987, 93, 94, 95, 97, 1998 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #ifndef _C_TREE_H
  22 #define _C_TREE_H
  23
  24 /* Language-dependent contents of an identifier.  */
  25
  26 /* The limbo_value is used for block level extern declarations, which need
  27    to be type checked against subsequent extern declarations.  They can't
  28    be referenced after they fall out of scope, so they can't be global.  */
  29
  30 struct lang_identifier
  31 {
  32   struct tree_identifier ignore;
  33   tree global_value, local_value, label_value, implicit_decl;
  34   tree error_locus, limbo_value;
  35 };
  36
  37 /* Macros for access to language-specific slots in an identifier.  */
  38 /* Each of these slots contains a DECL node or null.  */
  39
  40 /* This represents the value which the identifier has in the
  41    file-scope namespace.  */
  42 #define IDENTIFIER_GLOBAL_VALUE(NODE)   \
  43   (((struct lang_identifier *) (NODE))->global_value)
  44 /* This represents the value which the identifier has in the current
  45    scope.  */
  46 #define IDENTIFIER_LOCAL_VALUE(NODE)    \
  47   (((struct lang_identifier *) (NODE))->local_value)
  48 /* This represents the value which the identifier has as a label in
  49    the current label scope.  */
  50 #define IDENTIFIER_LABEL_VALUE(NODE)    \
  51   (((struct lang_identifier *) (NODE))->label_value)
  52 /* This records the extern decl of this identifier, if it has had one
  53    at any point in this compilation.  */
  54 #define IDENTIFIER_LIMBO_VALUE(NODE)    \
  55   (((struct lang_identifier *) (NODE))->limbo_value)
  56 /* This records the implicit function decl of this identifier, if it
  57    has had one at any point in this compilation.  */
  58 #define IDENTIFIER_IMPLICIT_DECL(NODE)  \
  59   (((struct lang_identifier *) (NODE))->implicit_decl)
  60 /* This is the last function in which we printed an "undefined variable"
  61    message for this identifier.  Value is a FUNCTION_DECL or null.  */
  62 #define IDENTIFIER_ERROR_LOCUS(NODE)    \
  63   (((struct lang_identifier *) (NODE))->error_locus)
  64
  65 /* In identifiers, C uses the following fields in a special way:
  66    TREE_PUBLIC        to record that there was a previous local extern decl.
  67    TREE_USED          to record that such a decl was used.
  68    TREE_ADDRESSABLE   to record that the address of such a decl was used.  */
  69
  70 /* Nonzero means reject anything that ANSI standard C forbids.  */
  71 extern int pedantic;
  72
  73 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is read-only.  */
  74 #define C_TYPE_FIELDS_READONLY(type) TREE_LANG_FLAG_1 (type)
  75
  76 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is volatile.  */
  77 #define C_TYPE_FIELDS_VOLATILE(type) TREE_LANG_FLAG_2 (type)
  78
  79 /* In a RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE
  80    nonzero if the definition of the type has already started.  */
  81 #define C_TYPE_BEING_DEFINED(type) TYPE_LANG_FLAG_0 (type)
  82
  83 /* C types are partitioned into three subsets: object, function, and
  84    incomplete types.  */
  85 #define C_TYPE_OBJECT_P(type) \
  86   (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type))
  87
  88 #define C_TYPE_FUNCTION_P(type) \
  89   (TREE_CODE (type) == FUNCTION_TYPE)
  90
  91 #define C_TYPE_INCOMPLETE_P(type) \
  92   (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type) == 0)
  93
  94 /* For convenience we define a single macro to identify the class of
  95    object or incomplete types.  */
  96 #define C_TYPE_OBJECT_OR_INCOMPLETE_P(type) \
  97   (!C_TYPE_FUNCTION_P (type))
  98
  99 /* In a RECORD_TYPE, a sorted array of the fields of the type.  */
 100 struct lang_type
 101 {
 102   int len;
 103   tree elts[1];
 104 };
 105
 106 /* Mark which labels are explicitly declared.
 107    These may be shadowed, and may be referenced from nested functions.  */
 108 #define C_DECLARED_LABEL_FLAG(label) TREE_LANG_FLAG_1 (label)
 109
 110 /* Record whether a type or decl was written with nonconstant size.
 111    Note that TYPE_SIZE may have simplified to a constant.  */
 112 #define C_TYPE_VARIABLE_SIZE(type) TYPE_LANG_FLAG_1 (type)
 113 #define C_DECL_VARIABLE_SIZE(type) DECL_LANG_FLAG_0 (type)
 114
 115 /* Record in each node resulting from a binary operator
 116    what operator was specified for it.  */
 117 #define C_EXP_ORIGINAL_CODE(exp) ((enum tree_code) TREE_COMPLEXITY (exp))
 118
 119 #if 0 /* Not used.  */
 120 /* Record whether a decl for a function or function pointer has
 121    already been mentioned (in a warning) because it was called
 122    but didn't have a prototype.  */
 123 #define C_MISSING_PROTOTYPE_WARNED(decl) DECL_LANG_FLAG_2(decl)
 124 #endif
 125
 126 /* Store a value in that field.  */
 127 #define C_SET_EXP_ORIGINAL_CODE(exp, code) \
 128   (TREE_COMPLEXITY (exp) = (int) (code))
 129
 130 /* Record whether a typedef for type `int' was actually `signed int'.  */
 131 #define C_TYPEDEF_EXPLICITLY_SIGNED(exp) DECL_LANG_FLAG_1 ((exp))
 132
 133 /* Nonzero for a declaration of a built in function if there has been no
 134    occasion that would declare the function in ordinary C.
 135    Using the function draws a pedantic warning in this case.  */
 136 #define C_DECL_ANTICIPATED(exp) DECL_LANG_FLAG_3 ((exp))
 137
 138 /* For FUNCTION_TYPE, a hidden list of types of arguments.  The same as
 139    TYPE_ARG_TYPES for functions with prototypes, but created for functions
 140    without prototypes.  */
 141 #define TYPE_ACTUAL_ARG_TYPES(NODE) TYPE_NONCOPIED_PARTS (NODE)
 142
 143 /* In a FIELD_DECL, nonzero if the decl was originally a bitfield.  */
 144 #define DECL_C_BIT_FIELD(NODE) DECL_LANG_FLAG_4 (NODE)
 145
 146 /* Nonzero if the type T promotes to itself.
 147    ANSI C states explicitly the list of types that promote;
 148    in particular, short promotes to int even if they have the same width.  */
 149 #define C_PROMOTING_INTEGER_TYPE_P(t)                           \
 150   (TREE_CODE ((t)) == INTEGER_TYPE                              \
 151    && (TYPE_MAIN_VARIANT (t) == char_type_node                  \
 152        || TYPE_MAIN_VARIANT (t) == signed_char_type_node        \
 153        || TYPE_MAIN_VARIANT (t) == unsigned_char_type_node      \
 154        || TYPE_MAIN_VARIANT (t) == short_integer_type_node      \
 155        || TYPE_MAIN_VARIANT (t) == short_unsigned_type_node))
 156
 157 /* In a VAR_DECL, means the variable is really an iterator.  */
 158 #define ITERATOR_P(D) (DECL_LANG_FLAG_4(D))
 159
 160 /* In a VAR_DECL for an iterator, means we are within
 161    an explicit loop over that iterator.  */
 162 #define ITERATOR_BOUND_P(NODE) ((NODE)->common.readonly_flag)
 163 \f
 164 /* in c-lang.c and objc-act.c */
 165 extern tree lookup_interface                    PROTO((tree));
 166 extern tree is_class_name                       PROTO((tree));
 167 extern void maybe_objc_check_decl               PROTO((tree));
 168 extern void finish_file                         PROTO((void));
 169 extern int maybe_objc_comptypes                 PROTO((tree, tree, int));
 170 extern tree maybe_building_objc_message_expr    PROTO((void));
 171 extern tree maybe_objc_method_name              PROTO((tree));
 172 extern int recognize_objc_keyword               PROTO((void));
 173 extern tree build_objc_string                   PROTO((int, char *));
 174 \f
 175 /* in c-aux-info.c */
 176 extern void gen_aux_info_record                 PROTO((tree, int, int, int));
 177
 178 /* in c-common.c */
 179 extern void declare_function_name               PROTO((void));
 180 extern void decl_attributes                     PROTO((tree, tree, tree));
 181 extern void init_function_format_info           PROTO((void));
 182 extern void check_function_format               PROTO((tree, tree, tree));
 183 extern int c_get_alias_set                      PROTO((tree));
 184 extern void c_apply_type_quals_to_decl          PROTO((int, tree));
 185 /* Print an error message for invalid operands to arith operation CODE.
 186    NOP_EXPR is used as a special case (see truthvalue_conversion).  */
 187 extern void binary_op_error                     PROTO((enum tree_code));
 188 extern void c_expand_expr_stmt                  PROTO((tree));
 189 extern void c_expand_start_cond                 PROTO((tree, int, int));
 190 extern void c_expand_start_else                 PROTO((void));
 191 extern void c_expand_end_cond                   PROTO((void));
 192 /* Validate the expression after `case' and apply default promotions.  */
 193 extern tree check_case_value                    PROTO((tree));
 194 /* Concatenate a list of STRING_CST nodes into one STRING_CST.  */
 195 extern tree combine_strings                     PROTO((tree));
 196 extern void constant_expression_warning         PROTO((tree));
 197 extern tree convert_and_check                   PROTO((tree, tree));
 198 extern void overflow_warning                    PROTO((tree));
 199 extern void unsigned_conversion_warning         PROTO((tree, tree));
 200 /* Read the rest of the current #-directive line.  */
 201 #if USE_CPPLIB
 202 extern char *get_directive_line                 PROTO((void));
 203 #define GET_DIRECTIVE_LINE() get_directive_line ()
 204 #else
 205 extern char *get_directive_line                 PROTO((FILE *));
 206 #define GET_DIRECTIVE_LINE() get_directive_line (finput)
 207 #endif
 208
 209 /* Subroutine of build_binary_op, used for comparison operations.
 210    See if the operands have both been converted from subword integer types
 211    and, if so, perhaps change them both back to their original type.  */
 212 extern tree shorten_compare                     PROTO((tree *, tree *, tree *, enum tree_code *));
 213 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
 214    or validate its data type for an `if' or `while' statement or ?..: exp. */
 215 extern tree truthvalue_conversion               PROTO((tree));
 216 extern tree type_for_mode                       PROTO((enum machine_mode, int));
 217 extern tree type_for_size                       PROTO((unsigned, int));
 218
 219 /* in c-convert.c */
 220 extern tree convert                             PROTO((tree, tree));
 221
 222 /* in c-decl.c */
 223 /* Standard named or nameless data types of the C compiler.  */
 224 extern tree char_array_type_node;
 225 extern tree char_type_node;
 226 extern tree const_ptr_type_node;
 227 extern tree const_string_type_node;
 228 extern tree default_function_type;
 229 extern tree double_ftype_double;
 230 extern tree double_ftype_double_double;
 231 extern tree double_type_node;
 232 extern tree float_type_node;
 233 #if HOST_BITS_PER_WIDE_INT >= 64
 234 extern tree intTI_type_node;
 235 #endif
 236 extern tree intDI_type_node;
 237 extern tree intHI_type_node;
 238 extern tree intQI_type_node;
 239 extern tree intSI_type_node;
 240 extern tree int_array_type_node;
 241 extern tree int_ftype_cptr_cptr_sizet;
 242 extern tree int_ftype_int;
 243 extern tree int_ftype_ptr_ptr_int;
 244 extern tree int_ftype_string_string;
 245 extern tree integer_type_node;
 246 extern tree long_double_type_node;
 247 extern tree long_ftype_long;
 248 extern tree long_integer_type_node;
 249 extern tree long_long_integer_type_node;
 250 extern tree long_long_unsigned_type_node;
 251 extern tree long_unsigned_type_node;
 252 extern tree complex_integer_type_node;
 253 extern tree complex_float_type_node;
 254 extern tree complex_double_type_node;
 255 extern tree complex_long_double_type_node;
 256 extern tree ptr_type_node;
 257 extern tree ptrdiff_type_node;
 258 extern tree short_integer_type_node;
 259 extern tree short_unsigned_type_node;
 260 extern tree signed_char_type_node;
 261 extern tree signed_wchar_type_node;
 262 extern tree string_ftype_ptr_ptr;
 263 extern tree string_type_node;
 264 extern tree unsigned_char_type_node;
 265 #if HOST_BITS_PER_WIDE_INT >= 64
 266 extern tree unsigned_intTI_type_node;
 267 #endif
 268 extern tree unsigned_intDI_type_node;
 269 extern tree unsigned_intHI_type_node;
 270 extern tree unsigned_intQI_type_node;
 271 extern tree unsigned_intSI_type_node;
 272 extern tree unsigned_type_node;
 273 extern tree unsigned_wchar_type_node;
 274 extern tree void_ftype_ptr_int_int;
 275 extern tree void_ftype_ptr_ptr_int;
 276 extern tree void_type_node;
 277 extern tree wchar_array_type_node;
 278 extern tree wchar_type_node;
 279 extern tree boolean_type_node;
 280 extern tree boolean_true_node;
 281 extern tree boolean_false_node;
 282
 283 extern tree build_enumerator                    PROTO((tree, tree));
 284 /* Declare a predefined function.  Return the declaration.  */
 285 extern tree builtin_function                    PROTO((char *, tree, enum built_in_function function_, char *));
 286 /* Add qualifiers to a type, in the fashion for C.  */
 287 extern tree c_build_qualified_type              PROTO((tree, int));
 288 #define c_build_type_variant(TYPE, CONST_P, VOLATILE_P)           \
 289   c_build_qualified_type (TYPE,                                   \
 290                           ((CONST_P) ? TYPE_QUAL_CONST : 0) |     \
 291                           ((VOLATILE_P) ? TYPE_QUAL_VOLATILE : 0))
 292 extern int  c_decode_option                     PROTO((int, char **));
 293 extern void c_mark_varargs                      PROTO((void));
 294 extern tree check_identifier                    PROTO((tree, tree));
 295 extern void clear_parm_order                    PROTO((void));
 296 extern tree combine_parm_decls                  PROTO((tree, tree, int));
 297 extern int  complete_array_type                 PROTO((tree, tree, int));
 298 extern void declare_parm_level                  PROTO((int));
 299 extern tree define_label                        PROTO((char *, int, tree));
 300 extern void delete_block                        PROTO((tree));
 301 extern void finish_decl                         PROTO((tree, tree, tree));
 302 extern void finish_decl_top_level               PROTO((tree, tree, tree));
 303 extern tree finish_enum                         PROTO((tree, tree, tree));
 304 extern void finish_function                     PROTO((int));
 305 extern tree finish_struct                       PROTO((tree, tree, tree));
 306 extern tree get_parm_info                       PROTO((int));
 307 extern tree getdecls                            PROTO((void));
 308 extern tree gettags                             PROTO((void));
 309 extern int  global_bindings_p                   PROTO((void));
 310 extern tree grokfield                           PROTO((char *, int, tree, tree, tree));
 311 extern tree groktypename                        PROTO((tree));
 312 extern tree groktypename_in_parm_context        PROTO((tree));
 313 extern tree implicitly_declare                  PROTO((tree));
 314 extern int  in_parm_level_p                     PROTO((void));
 315 extern void init_decl_processing                PROTO((void));
 316 extern void insert_block                        PROTO((tree));
 317 extern void keep_next_level                     PROTO((void));
 318 extern int  kept_level_p                        PROTO((void));
 319 extern tree lookup_label                        PROTO((tree));
 320 extern tree lookup_name                         PROTO((tree));
 321 extern tree lookup_name_current_level           PROTO((tree));
 322 extern tree lookup_name_current_level_global    PROTO((tree));
 323 extern tree maybe_build_cleanup                 PROTO((tree));
 324 extern void parmlist_tags_warning               PROTO((void));
 325 extern void pending_xref_error                  PROTO((void));
 326 extern void pop_c_function_context              PROTO((void));
 327 extern void pop_label_level                     PROTO((void));
 328 extern tree poplevel                            PROTO((int, int, int));
 329 extern void print_lang_decl                     PROTO((FILE *, tree, int));
 330 extern void print_lang_identifier               PROTO((FILE *, tree, int));
 331 extern void print_lang_type                     PROTO((FILE *, tree, int));
 332 extern void push_c_function_context             PROTO((void));
 333 extern void push_label_level                    PROTO((void));
 334 extern void push_parm_decl                      PROTO((tree));
 335 extern tree pushdecl                            PROTO((tree));
 336 extern tree pushdecl_top_level                  PROTO((tree));
 337 extern void pushlevel                           PROTO((int));
 338 extern void pushtag                             PROTO((tree, tree));
 339 extern void set_block                           PROTO((tree));
 340 extern tree shadow_label                        PROTO((tree));
 341 extern void shadow_record_fields                PROTO((tree));
 342 extern void shadow_tag                          PROTO((tree));
 343 extern void shadow_tag_warned                   PROTO((tree, int));
 344 extern tree start_enum                          PROTO((tree));
 345 extern int  start_function                      PROTO((tree, tree, tree,
 346                                                        tree, int));
 347 extern tree start_decl                          PROTO((tree, tree, int,
 348                                                        tree, tree));
 349 extern tree start_struct                        PROTO((enum tree_code, tree));
 350 extern void store_parm_decls                    PROTO((void));
 351 extern tree xref_tag                            PROTO((enum tree_code, tree));
 352
 353 /* in c-typeck.c */
 354 extern tree require_complete_type               PROTO((tree));
 355 extern void incomplete_type_error               PROTO((tree, tree));
 356 /* Given two integer or real types, return the type for their sum.
 357    Given two compatible ANSI C types, returns the merged type.  */
 358 extern tree common_type                         PROTO((tree, tree));
 359 extern int comptypes                            PROTO((tree, tree));
 360 extern int self_promoting_args_p                PROTO((tree));
 361 extern tree c_sizeof                            PROTO((tree));
 362 extern tree c_sizeof_nowarn                     PROTO((tree));
 363 extern tree c_size_in_bytes                     PROTO((tree));
 364 extern tree c_alignof                           PROTO((tree));
 365 extern tree c_alignof_expr                      PROTO((tree));
 366 extern tree default_conversion                  PROTO((tree));
 367 extern tree build_component_ref                 PROTO((tree, tree));
 368 extern tree build_indirect_ref                  PROTO((tree, char *));
 369 extern tree build_array_ref                     PROTO((tree, tree));
 370 extern tree build_function_call                 PROTO((tree, tree));
 371 extern tree parser_build_binary_op              PROTO((enum tree_code,
 372                                                        tree, tree));
 373 extern tree build_binary_op                     PROTO((enum tree_code,
 374                                                        tree, tree, int));
 375 extern tree build_unary_op                      PROTO((enum tree_code,
 376                                                        tree, int));
 377 extern int lvalue_p                             PROTO((tree));
 378 extern int lvalue_or_else                       PROTO((tree, char *));
 379 extern void readonly_warning                    PROTO((tree, char *));
 380 extern int mark_addressable                     PROTO((tree));
 381 extern tree build_conditional_expr              PROTO((tree, tree, tree));
 382 extern tree build_compound_expr                 PROTO((tree));
 383 extern tree build_c_cast                        PROTO((tree, tree));
 384 extern tree build_modify_expr                   PROTO((tree, enum tree_code,
 385                                                        tree));
 386 extern tree initializer_constant_valid_p        PROTO((tree, tree));
 387 extern void store_init_value                    PROTO((tree, tree));
 388 extern void error_init                          PROTO((char *));
 389 extern void pedwarn_init                        PROTO((char *));
 390 extern void start_init                          PROTO((tree, tree, int));
 391 extern void finish_init                         PROTO((void));
 392 extern void really_start_incremental_init       PROTO((tree));
 393 extern void push_init_level                     PROTO((int));
 394 extern tree pop_init_level                      PROTO((int));
 395 extern void set_init_index                      PROTO((tree, tree));
 396 extern void set_init_label                      PROTO((tree));
 397 extern void process_init_element                PROTO((tree));
 398 extern void c_expand_asm_operands               PROTO((tree, tree, tree, tree,
 399                                                        int, char *, int));
 400 extern void c_expand_return                     PROTO((tree));
 401 extern tree c_expand_start_case                 PROTO((tree));
 402
 403 /* in c-iterate.c */
 404 extern void init_iterators                      PROTO((void));
 405 extern void iterator_expand                     PROTO((tree));
 406 extern void iterator_for_loop_start             PROTO((tree));
 407 extern void iterator_for_loop_end               PROTO((tree));
 408 extern void iterator_for_loop_record            PROTO((tree));
 409 extern void push_iterator_stack                 PROTO((void));
 410 extern void pop_iterator_stack                  PROTO((void));
 411
 412 /* Set to 0 at beginning of a function definition, set to 1 if
 413    a return statement that specifies a return value is seen.  */
 414
 415 extern int current_function_returns_value;
 416
 417 /* Set to 0 at beginning of a function definition, set to 1 if
 418    a return statement with no argument is seen.  */
 419
 420 extern int current_function_returns_null;
 421
 422 /* Nonzero means the expression being parsed will never be evaluated.
 423    This is a count, since unevaluated expressions can nest.  */
 424
 425 extern int skip_evaluation;
 426
 427 /* Nonzero means `$' can be in an identifier.  */
 428
 429 extern int dollars_in_ident;
 430
 431 /* Nonzero means allow type mismatches in conditional expressions;
 432    just make their values `void'.   */
 433
 434 extern int flag_cond_mismatch;
 435
 436 /* Nonzero means don't recognize the keyword `asm'.  */
 437
 438 extern int flag_no_asm;
 439
 440 /* Nonzero means environment is hosted (i.e., not freestanding) */
 441
 442 extern int flag_hosted;
 443
 444 /* Nonzero means ignore `#ident' directives.  */
 445
 446 extern int flag_no_ident;
 447
 448 /* Nonzero means warn about implicit declarations.  */
 449
 450 extern int warn_implicit;
 451
 452 /* Nonzero means give string constants the type `const char *'
 453    to get extra warnings from them.  These warnings will be too numerous
 454    to be useful, except in thoroughly ANSIfied programs.  */
 455
 456 extern int flag_const_strings;
 457
 458 /* Nonzero means warn about sizeof (function) or addition/subtraction
 459    of function pointers.  */
 460
 461 extern int warn_pointer_arith;
 462
 463 /* Nonzero means warn for all old-style non-prototype function decls.  */
 464
 465 extern int warn_strict_prototypes;
 466
 467 /* Nonzero means warn about multiple (redundant) decls for the same single
 468    variable or function.  */
 469
 470 extern int warn_redundant_decls;
 471
 472 /* Nonzero means warn about extern declarations of objects not at
 473    file-scope level and about *all* declarations of functions (whether
 474    extern or static) not at file-scope level.  Note that we exclude
 475    implicit function declarations.  To get warnings about those, use
 476    -Wimplicit.  */
 477
 478 extern int warn_nested_externs;
 479
 480 /* Nonzero means warn about pointer casts that can drop a type qualifier
 481    from the pointer target type.  */
 482
 483 extern int warn_cast_qual;
 484
 485 /* Nonzero means warn when casting a function call to a type that does
 486    not match the return type (e.g. (float)sqrt() or (anything*)malloc()
 487    when there is no previous declaration of sqrt or malloc.  */
 488
 489 extern int warn_bad_function_cast;
 490
 491 /* Warn about functions which might be candidates for attribute noreturn. */
 492
 493 extern int warn_missing_noreturn;
 494
 495 /* Warn about traditional constructs whose meanings changed in ANSI C.  */
 496
 497 extern int warn_traditional;
 498
 499 /* Warn about *printf or *scanf format/argument anomalies. */
 500
 501 extern int warn_format;
 502
 503 /* Warn about a subscript that has type char.  */
 504
 505 extern int warn_char_subscripts;
 506
 507 /* Warn if a type conversion is done that might have confusing results.  */
 508
 509 extern int warn_conversion;
 510
 511 /* Warn if main is suspicious. */
 512
 513 extern int warn_main;
 514
 515 /* Nonzero means do some things the same way PCC does.  */
 516
 517 extern int flag_traditional;
 518
 519 /* Nonzero means use the ISO C9x dialect of C.  */
 520
 521 extern int flag_isoc9x;
 522
 523 /* Nonzero means to allow single precision math even if we're generally
 524    being traditional. */
 525 extern int flag_allow_single_precision;
 526
 527 /* Nonzero means warn about suggesting putting in ()'s.  */
 528
 529 extern int warn_parentheses;
 530
 531 /* Warn if initializer is not completely bracketed.  */
 532
 533 extern int warn_missing_braces;
 534
 535 /* Warn about comparison of signed and unsigned values.  */
 536
 537 extern int warn_sign_compare;
 538
 539 /* Warn about multicharacter constants.  */
 540
 541 extern int warn_multichar;
 542
 543 /* Warn about long long.  */
 544
 545 extern int warn_long_long;
 546
 547 /* Nonzero means we are reading code that came from a system header file.  */
 548
 549 extern int system_header_p;
 550
 551 /* Nonzero enables objc features.  */
 552
 553 extern int doing_objc_thang;
 554
 555 /* In c-decl.c */
 556 extern void finish_incomplete_decl PROTO((tree));
 557
 558 #endif /* not _C_TREE_H */