1 /* Definitions for C parsing and type checking.
2 Copyright (C) 1987, 1993, 1994, 1995, 1997 Free Software Foundation, Inc.
4 This file is part of GNU CC.
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)
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.
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. */
24 /* Language-dependent contents of an identifier. */
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. */
30 struct lang_identifier
32 struct tree_identifier ignore;
33 tree global_value, local_value, label_value, implicit_decl;
34 tree error_locus, limbo_value;
37 /* Macros for access to language-specific slots in an identifier. */
38 /* Each of these slots contains a DECL node or null. */
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
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)
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. */
70 /* Nonzero means reject anything that ANSI standard C forbids. */
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)
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)
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)
83 /* In a RECORD_TYPE, a sorted array of the fields of the type. */
90 /* Mark which labels are explicitly declared.
91 These may be shadowed, and may be referenced from nested functions. */
92 #define C_DECLARED_LABEL_FLAG(label) TREE_LANG_FLAG_1 (label)
94 /* Record whether a type or decl was written with nonconstant size.
95 Note that TYPE_SIZE may have simplified to a constant. */
96 #define C_TYPE_VARIABLE_SIZE(type) TYPE_LANG_FLAG_1 (type)
97 #define C_DECL_VARIABLE_SIZE(type) DECL_LANG_FLAG_0 (type)
99 /* Record in each node resulting from a binary operator
100 what operator was specified for it. */
101 #define C_EXP_ORIGINAL_CODE(exp) ((enum tree_code) TREE_COMPLEXITY (exp))
103 #if 0 /* Not used. */
104 /* Record whether a decl for a function or function pointer has
105 already been mentioned (in a warning) because it was called
106 but didn't have a prototype. */
107 #define C_MISSING_PROTOTYPE_WARNED(decl) DECL_LANG_FLAG_2(decl)
110 /* Store a value in that field. */
111 #define C_SET_EXP_ORIGINAL_CODE(exp, code) \
112 (TREE_COMPLEXITY (exp) = (int) (code))
114 /* Record whether a typedef for type `int' was actually `signed int'. */
115 #define C_TYPEDEF_EXPLICITLY_SIGNED(exp) DECL_LANG_FLAG_1 ((exp))
117 /* Nonzero for a declaration of a built in function if there has been no
118 occasion that would declare the function in ordinary C.
119 Using the function draws a pedantic warning in this case. */
120 #define C_DECL_ANTICIPATED(exp) DECL_LANG_FLAG_3 ((exp))
122 /* For FUNCTION_TYPE, a hidden list of types of arguments. The same as
123 TYPE_ARG_TYPES for functions with prototypes, but created for functions
124 without prototypes. */
125 #define TYPE_ACTUAL_ARG_TYPES(NODE) TYPE_NONCOPIED_PARTS (NODE)
127 /* In a FIELD_DECL, nonzero if the decl was originally a bitfield. */
128 #define DECL_C_BIT_FIELD(NODE) DECL_LANG_FLAG_4 (NODE)
130 /* Nonzero if the type T promotes to itself.
131 ANSI C states explicitly the list of types that promote;
132 in particular, short promotes to int even if they have the same width. */
133 #define C_PROMOTING_INTEGER_TYPE_P(t) \
134 (TREE_CODE ((t)) == INTEGER_TYPE \
135 && (TYPE_MAIN_VARIANT (t) == char_type_node \
136 || TYPE_MAIN_VARIANT (t) == signed_char_type_node \
137 || TYPE_MAIN_VARIANT (t) == unsigned_char_type_node \
138 || TYPE_MAIN_VARIANT (t) == short_integer_type_node \
139 || TYPE_MAIN_VARIANT (t) == short_unsigned_type_node))
141 /* In a VAR_DECL, means the variable is really an iterator. */
142 #define ITERATOR_P(D) (DECL_LANG_FLAG_4(D))
144 /* In a VAR_DECL for an iterator, means we are within
145 an explicit loop over that iterator. */
146 #define ITERATOR_BOUND_P(NODE) ((NODE)->common.readonly_flag)
148 /* in c-lang.c and objc-act.c */
149 extern tree lookup_interface PROTO((tree));
150 extern tree is_class_name PROTO((tree));
151 extern void maybe_objc_check_decl PROTO((tree));
152 extern void finish_file PROTO((void));
153 extern int maybe_objc_comptypes PROTO((tree, tree, int));
154 extern tree maybe_building_objc_message_expr PROTO((void));
155 extern tree maybe_objc_method_name PROTO((tree));
156 extern int recognize_objc_keyword PROTO((void));
157 extern tree build_objc_string PROTO((int, char *));
159 /* in c-aux-info.c */
160 extern void gen_aux_info_record PROTO((tree, int, int, int));
163 extern void declare_function_name PROTO((void));
164 extern void decl_attributes PROTO((tree, tree, tree));
165 extern void init_function_format_info PROTO((void));
166 extern void check_function_format PROTO((tree, tree, tree));
167 extern int c_get_alias_set PROTO((tree));
168 /* Print an error message for invalid operands to arith operation CODE.
169 NOP_EXPR is used as a special case (see truthvalue_conversion). */
170 extern void binary_op_error PROTO((enum tree_code));
171 extern void c_expand_expr_stmt PROTO((tree));
172 extern void c_expand_start_cond PROTO((tree, int, int));
173 extern void c_expand_start_else PROTO((void));
174 extern void c_expand_end_cond PROTO((void));
175 /* Validate the expression after `case' and apply default promotions. */
176 extern tree check_case_value PROTO((tree));
177 /* Concatenate a list of STRING_CST nodes into one STRING_CST. */
178 extern tree combine_strings PROTO((tree));
179 extern void constant_expression_warning PROTO((tree));
180 extern tree convert_and_check PROTO((tree, tree));
181 extern void overflow_warning PROTO((tree));
182 extern void unsigned_conversion_warning PROTO((tree, tree));
183 /* Read the rest of the current #-directive line. */
185 extern char *get_directive_line PROTO((void));
186 #define GET_DIRECTIVE_LINE() get_directive_line ()
188 extern char *get_directive_line PROTO((FILE *));
189 #define GET_DIRECTIVE_LINE() get_directive_line (finput)
192 /* Subroutine of build_binary_op, used for comparison operations.
193 See if the operands have both been converted from subword integer types
194 and, if so, perhaps change them both back to their original type. */
195 extern tree shorten_compare PROTO((tree *, tree *, tree *, enum tree_code *));
196 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
197 or validate its data type for an `if' or `while' statement or ?..: exp. */
198 extern tree truthvalue_conversion PROTO((tree));
199 extern tree type_for_mode PROTO((enum machine_mode, int));
200 extern tree type_for_size PROTO((unsigned, int));
203 extern tree convert PROTO((tree, tree));
206 /* Standard named or nameless data types of the C compiler. */
207 extern tree char_array_type_node;
208 extern tree char_type_node;
209 extern tree const_ptr_type_node;
210 extern tree const_string_type_node;
211 extern tree default_function_type;
212 extern tree double_ftype_double;
213 extern tree double_ftype_double_double;
214 extern tree double_type_node;
215 extern tree float_type_node;
216 #if HOST_BITS_PER_WIDE_INT >= 64
217 extern tree intTI_type_node;
219 extern tree intDI_type_node;
220 extern tree intHI_type_node;
221 extern tree intQI_type_node;
222 extern tree intSI_type_node;
223 extern tree int_array_type_node;
224 extern tree int_ftype_cptr_cptr_sizet;
225 extern tree int_ftype_int;
226 extern tree int_ftype_ptr_ptr_int;
227 extern tree int_ftype_string_string;
228 extern tree integer_type_node;
229 extern tree long_double_type_node;
230 extern tree long_ftype_long;
231 extern tree long_integer_type_node;
232 extern tree long_long_integer_type_node;
233 extern tree long_long_unsigned_type_node;
234 extern tree long_unsigned_type_node;
235 extern tree complex_integer_type_node;
236 extern tree complex_float_type_node;
237 extern tree complex_double_type_node;
238 extern tree complex_long_double_type_node;
239 extern tree ptr_type_node;
240 extern tree ptrdiff_type_node;
241 extern tree short_integer_type_node;
242 extern tree short_unsigned_type_node;
243 extern tree signed_char_type_node;
244 extern tree signed_wchar_type_node;
245 extern tree string_ftype_ptr_ptr;
246 extern tree string_type_node;
247 extern tree unsigned_char_type_node;
248 #if HOST_BITS_PER_WIDE_INT >= 64
249 extern tree unsigned_intTI_type_node;
251 extern tree unsigned_intDI_type_node;
252 extern tree unsigned_intHI_type_node;
253 extern tree unsigned_intQI_type_node;
254 extern tree unsigned_intSI_type_node;
255 extern tree unsigned_type_node;
256 extern tree unsigned_wchar_type_node;
257 extern tree void_ftype_ptr_int_int;
258 extern tree void_ftype_ptr_ptr_int;
259 extern tree void_type_node;
260 extern tree wchar_array_type_node;
261 extern tree wchar_type_node;
262 extern tree boolean_type_node;
263 extern tree boolean_true_node;
264 extern tree boolean_false_node;
266 extern tree build_enumerator PROTO((tree, tree));
267 /* Declare a predefined function. Return the declaration. */
268 extern tree builtin_function PROTO((char *, tree, enum built_in_function function_, char *));
269 /* Add qualifiers to a type, in the fashion for C. */
270 extern tree c_build_type_variant PROTO((tree, int, int));
271 extern int c_decode_option PROTO((int, char **));
272 extern void c_mark_varargs PROTO((void));
273 extern tree check_identifier PROTO((tree, tree));
274 extern void clear_parm_order PROTO((void));
275 extern tree combine_parm_decls PROTO((tree, tree, int));
276 extern int complete_array_type PROTO((tree, tree, int));
277 extern void declare_parm_level PROTO((int));
278 extern tree define_label PROTO((char *, int, tree));
279 extern void delete_block PROTO((tree));
280 extern void finish_decl PROTO((tree, tree, tree));
281 extern void finish_decl_top_level PROTO((tree, tree, tree));
282 extern tree finish_enum PROTO((tree, tree, tree));
283 extern void finish_function PROTO((int));
284 extern tree finish_struct PROTO((tree, tree, tree));
285 extern tree get_parm_info PROTO((int));
286 extern tree getdecls PROTO((void));
287 extern tree gettags PROTO((void));
288 extern int global_bindings_p PROTO((void));
289 extern tree grokfield PROTO((char *, int, tree, tree, tree));
290 extern tree groktypename PROTO((tree));
291 extern tree groktypename_in_parm_context PROTO((tree));
292 extern tree implicitly_declare PROTO((tree));
293 extern int in_parm_level_p PROTO((void));
294 extern void init_decl_processing PROTO((void));
295 extern void insert_block PROTO((tree));
296 extern void keep_next_level PROTO((void));
297 extern int kept_level_p PROTO((void));
298 extern tree lookup_label PROTO((tree));
299 extern tree lookup_name PROTO((tree));
300 extern tree lookup_name_current_level PROTO((tree));
301 extern tree lookup_name_current_level_global PROTO((tree));
302 extern tree maybe_build_cleanup PROTO((tree));
303 extern void parmlist_tags_warning PROTO((void));
304 extern void pending_xref_error PROTO((void));
305 extern void pop_c_function_context PROTO((void));
306 extern void pop_label_level PROTO((void));
307 extern tree poplevel PROTO((int, int, int));
308 extern void print_lang_decl PROTO((FILE *, tree, int));
309 extern void print_lang_identifier PROTO((FILE *, tree, int));
310 extern void print_lang_type PROTO((FILE *, tree, int));
311 extern void push_c_function_context PROTO((void));
312 extern void push_label_level PROTO((void));
313 extern void push_parm_decl PROTO((tree));
314 extern tree pushdecl PROTO((tree));
315 extern tree pushdecl_top_level PROTO((tree));
316 extern void pushlevel PROTO((int));
317 extern void pushtag PROTO((tree, tree));
318 extern void set_block PROTO((tree));
319 extern tree shadow_label PROTO((tree));
320 extern void shadow_record_fields PROTO((tree));
321 extern void shadow_tag PROTO((tree));
322 extern void shadow_tag_warned PROTO((tree, int));
323 extern tree start_enum PROTO((tree));
324 extern int start_function PROTO((tree, tree, tree,
326 extern tree start_decl PROTO((tree, tree, int,
328 extern tree start_struct PROTO((enum tree_code, tree));
329 extern void store_parm_decls PROTO((void));
330 extern tree xref_tag PROTO((enum tree_code, tree));
333 extern tree require_complete_type PROTO((tree));
334 extern void incomplete_type_error PROTO((tree, tree));
335 /* Given two integer or real types, return the type for their sum.
336 Given two compatible ANSI C types, returns the merged type. */
337 extern tree common_type PROTO((tree, tree));
338 extern int comptypes PROTO((tree, tree));
339 extern int self_promoting_args_p PROTO((tree));
340 extern tree c_sizeof PROTO((tree));
341 extern tree c_sizeof_nowarn PROTO((tree));
342 extern tree c_size_in_bytes PROTO((tree));
343 extern tree c_alignof PROTO((tree));
344 extern tree c_alignof_expr PROTO((tree));
345 extern tree default_conversion PROTO((tree));
346 extern tree build_component_ref PROTO((tree, tree));
347 extern tree build_indirect_ref PROTO((tree, char *));
348 extern tree build_array_ref PROTO((tree, tree));
349 extern tree build_function_call PROTO((tree, tree));
350 extern tree parser_build_binary_op PROTO((enum tree_code,
352 extern tree build_binary_op PROTO((enum tree_code,
354 extern tree build_unary_op PROTO((enum tree_code,
356 extern int lvalue_p PROTO((tree));
357 extern int lvalue_or_else PROTO((tree, char *));
358 extern void readonly_warning PROTO((tree, char *));
359 extern int mark_addressable PROTO((tree));
360 extern tree build_conditional_expr PROTO((tree, tree, tree));
361 extern tree build_compound_expr PROTO((tree));
362 extern tree build_c_cast PROTO((tree, tree));
363 extern tree build_modify_expr PROTO((tree, enum tree_code,
365 extern tree initializer_constant_valid_p PROTO((tree, tree));
366 extern void store_init_value PROTO((tree, tree));
367 extern void error_init PROTO((char *, char *,
369 extern void pedwarn_init PROTO((char *, char *,
371 extern void start_init PROTO((tree, tree, int));
372 extern void finish_init PROTO((void));
373 extern void really_start_incremental_init PROTO((tree));
374 extern void push_init_level PROTO((int));
375 extern tree pop_init_level PROTO((int));
376 extern void set_init_index PROTO((tree, tree));
377 extern void set_init_label PROTO((tree));
378 extern void process_init_element PROTO((tree));
379 extern void c_expand_asm_operands PROTO((tree, tree, tree, tree,
381 extern void c_expand_return PROTO((tree));
382 extern tree c_expand_start_case PROTO((tree));
385 extern void init_iterators PROTO((void));
386 extern void iterator_expand PROTO((tree));
387 extern void iterator_for_loop_start PROTO((tree));
388 extern void iterator_for_loop_end PROTO((tree));
389 extern void iterator_for_loop_record PROTO((tree));
390 extern void push_iterator_stack PROTO((void));
391 extern void pop_iterator_stack PROTO((void));
393 /* Set to 0 at beginning of a function definition, set to 1 if
394 a return statement that specifies a return value is seen. */
396 extern int current_function_returns_value;
398 /* Set to 0 at beginning of a function definition, set to 1 if
399 a return statement with no argument is seen. */
401 extern int current_function_returns_null;
403 /* Nonzero means the expression being parsed will never be evaluated.
404 This is a count, since unevaluated expressions can nest. */
406 extern int skip_evaluation;
408 /* Nonzero means `$' can be in an identifier. */
410 extern int dollars_in_ident;
412 /* Nonzero means allow type mismatches in conditional expressions;
413 just make their values `void'. */
415 extern int flag_cond_mismatch;
417 /* Nonzero means don't recognize the keyword `asm'. */
419 extern int flag_no_asm;
421 /* Nonzero means environment is hosted (i.e., not freestanding) */
423 extern int flag_hosted;
425 /* Nonzero means ignore `#ident' directives. */
427 extern int flag_no_ident;
429 /* Nonzero means warn about implicit declarations. */
431 extern int warn_implicit;
433 /* Nonzero means give string constants the type `const char *'
434 to get extra warnings from them. These warnings will be too numerous
435 to be useful, except in thoroughly ANSIfied programs. */
437 extern int flag_const_strings;
439 /* Nonzero means warn about sizeof (function) or addition/subtraction
440 of function pointers. */
442 extern int warn_pointer_arith;
444 /* Nonzero means warn for all old-style non-prototype function decls. */
446 extern int warn_strict_prototypes;
448 /* Nonzero means warn about multiple (redundant) decls for the same single
449 variable or function. */
451 extern int warn_redundant_decls;
453 /* Nonzero means warn about extern declarations of objects not at
454 file-scope level and about *all* declarations of functions (whether
455 extern or static) not at file-scope level. Note that we exclude
456 implicit function declarations. To get warnings about those, use
459 extern int warn_nested_externs;
461 /* Nonzero means warn about pointer casts that can drop a type qualifier
462 from the pointer target type. */
464 extern int warn_cast_qual;
466 /* Nonzero means warn when casting a function call to a type that does
467 not match the return type (e.g. (float)sqrt() or (anything*)malloc()
468 when there is no previous declaration of sqrt or malloc. */
470 extern int warn_bad_function_cast;
472 /* Warn about traditional constructs whose meanings changed in ANSI C. */
474 extern int warn_traditional;
476 /* Warn about *printf or *scanf format/argument anomalies. */
478 extern int warn_format;
480 /* Warn about a subscript that has type char. */
482 extern int warn_char_subscripts;
484 /* Warn if a type conversion is done that might have confusing results. */
486 extern int warn_conversion;
488 /* Warn if main is suspicious. */
490 extern int warn_main;
492 /* Nonzero means do some things the same way PCC does. */
494 extern int flag_traditional;
496 /* Nonzero means to allow single precision math even if we're generally
497 being traditional. */
498 extern int flag_allow_single_precision;
500 /* Nonzero means warn about suggesting putting in ()'s. */
502 extern int warn_parentheses;
504 /* Warn if initializer is not completely bracketed. */
506 extern int warn_missing_braces;
508 /* Warn about comparison of signed and unsigned values. */
510 extern int warn_sign_compare;
512 /* Warn about multicharacter constants. */
514 extern int warn_multichar;
516 /* Warn about long long. */
518 extern int warn_long_long;
520 /* Nonzero means we are reading code that came from a system header file. */
522 extern int system_header_p;
524 /* Nonzero enables objc features. */
526 extern int doing_objc_thang;
529 extern void finish_incomplete_decl PROTO((tree));
531 #endif /* not _C_TREE_H */