1 /* Definitions for C parsing and type checking.
2 Copyright (C) 1987, 1993, 1994, 1995, 1997, 1998,
3 1999, 2000 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
27 /* Language-dependent contents of an identifier. */
29 /* The limbo_value is used for block level extern declarations, which need
30 to be type checked against subsequent extern declarations. They can't
31 be referenced after they fall out of scope, so they can't be global. */
33 struct lang_identifier
35 struct tree_identifier ignore;
36 tree global_value, local_value, label_value, implicit_decl;
37 tree error_locus, limbo_value;
40 /* Macros for access to language-specific slots in an identifier. */
41 /* Each of these slots contains a DECL node or null. */
43 /* This represents the value which the identifier has in the
44 file-scope namespace. */
45 #define IDENTIFIER_GLOBAL_VALUE(NODE) \
46 (((struct lang_identifier *) (NODE))->global_value)
47 /* This represents the value which the identifier has in the current
49 #define IDENTIFIER_LOCAL_VALUE(NODE) \
50 (((struct lang_identifier *) (NODE))->local_value)
51 /* This represents the value which the identifier has as a label in
52 the current label scope. */
53 #define IDENTIFIER_LABEL_VALUE(NODE) \
54 (((struct lang_identifier *) (NODE))->label_value)
55 /* This records the extern decl of this identifier, if it has had one
56 at any point in this compilation. */
57 #define IDENTIFIER_LIMBO_VALUE(NODE) \
58 (((struct lang_identifier *) (NODE))->limbo_value)
59 /* This records the implicit function decl of this identifier, if it
60 has had one at any point in this compilation. */
61 #define IDENTIFIER_IMPLICIT_DECL(NODE) \
62 (((struct lang_identifier *) (NODE))->implicit_decl)
63 /* This is the last function in which we printed an "undefined variable"
64 message for this identifier. Value is a FUNCTION_DECL or null. */
65 #define IDENTIFIER_ERROR_LOCUS(NODE) \
66 (((struct lang_identifier *) (NODE))->error_locus)
68 /* In identifiers, C uses the following fields in a special way:
69 TREE_PUBLIC to record that there was a previous local extern decl.
70 TREE_USED to record that such a decl was used.
71 TREE_ADDRESSABLE to record that the address of such a decl was used. */
73 /* Nonzero means reject anything that ANSI standard C forbids. */
76 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is read-only. */
77 #define C_TYPE_FIELDS_READONLY(type) TREE_LANG_FLAG_1 (type)
79 /* In a RECORD_TYPE or UNION_TYPE, nonzero if any component is volatile. */
80 #define C_TYPE_FIELDS_VOLATILE(type) TREE_LANG_FLAG_2 (type)
82 /* In a RECORD_TYPE or UNION_TYPE or ENUMERAL_TYPE
83 nonzero if the definition of the type has already started. */
84 #define C_TYPE_BEING_DEFINED(type) TYPE_LANG_FLAG_0 (type)
86 /* C types are partitioned into three subsets: object, function, and
88 #define C_TYPE_OBJECT_P(type) \
89 (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type))
91 #define C_TYPE_FUNCTION_P(type) \
92 (TREE_CODE (type) == FUNCTION_TYPE)
94 #define C_TYPE_INCOMPLETE_P(type) \
95 (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type) == 0)
97 /* For convenience we define a single macro to identify the class of
98 object or incomplete types. */
99 #define C_TYPE_OBJECT_OR_INCOMPLETE_P(type) \
100 (!C_TYPE_FUNCTION_P (type))
102 /* In a RECORD_TYPE, a sorted array of the fields of the type. */
109 /* Mark which labels are explicitly declared.
110 These may be shadowed, and may be referenced from nested functions. */
111 #define C_DECLARED_LABEL_FLAG(label) TREE_LANG_FLAG_1 (label)
113 /* Record whether a type or decl was written with nonconstant size.
114 Note that TYPE_SIZE may have simplified to a constant. */
115 #define C_TYPE_VARIABLE_SIZE(type) TYPE_LANG_FLAG_1 (type)
116 #define C_DECL_VARIABLE_SIZE(type) DECL_LANG_FLAG_0 (type)
118 /* Record in each node resulting from a binary operator
119 what operator was specified for it. */
120 #define C_EXP_ORIGINAL_CODE(exp) ((enum tree_code) TREE_COMPLEXITY (exp))
122 #if 0 /* Not used. */
123 /* Record whether a decl for a function or function pointer has
124 already been mentioned (in a warning) because it was called
125 but didn't have a prototype. */
126 #define C_MISSING_PROTOTYPE_WARNED(decl) DECL_LANG_FLAG_2(decl)
129 /* Store a value in that field. */
130 #define C_SET_EXP_ORIGINAL_CODE(exp, code) \
131 (TREE_COMPLEXITY (exp) = (int) (code))
133 /* Record whether a typedef for type `int' was actually `signed int'. */
134 #define C_TYPEDEF_EXPLICITLY_SIGNED(exp) DECL_LANG_FLAG_1 ((exp))
136 /* Nonzero for a declaration of a built in function if there has been no
137 occasion that would declare the function in ordinary C.
138 Using the function draws a pedantic warning in this case. */
139 #define C_DECL_ANTICIPATED(exp) DECL_LANG_FLAG_3 ((exp))
141 /* For FUNCTION_TYPE, a hidden list of types of arguments. The same as
142 TYPE_ARG_TYPES for functions with prototypes, but created for functions
143 without prototypes. */
144 #define TYPE_ACTUAL_ARG_TYPES(NODE) TYPE_NONCOPIED_PARTS (NODE)
146 /* In a FIELD_DECL, nonzero if the decl was originally a bitfield. */
147 #define DECL_C_BIT_FIELD(NODE) DECL_LANG_FLAG_4 (NODE)
149 /* In a VAR_DECL, means the variable is really an iterator. */
150 #define ITERATOR_P(D) (DECL_LANG_FLAG_4(D))
152 /* In a VAR_DECL for an iterator, means we are within
153 an explicit loop over that iterator. */
154 #define ITERATOR_BOUND_P(NODE) ((NODE)->common.readonly_flag)
156 /* in c-lang.c and objc-act.c */
157 extern tree lookup_interface PARAMS ((tree));
158 extern tree is_class_name PARAMS ((tree));
159 extern void maybe_objc_check_decl PARAMS ((tree));
160 extern void finish_file PARAMS ((void));
161 extern int maybe_objc_comptypes PARAMS ((tree, tree, int));
162 extern tree maybe_building_objc_message_expr PARAMS ((void));
163 extern tree maybe_objc_method_name PARAMS ((tree));
164 extern int recognize_objc_keyword PARAMS ((void));
165 extern tree build_objc_string PARAMS ((int, const char *));
166 extern tree lookup_objc_ivar PARAMS ((tree));
169 extern void c_parse_init PARAMS ((void));
171 /* in c-aux-info.c */
172 extern void gen_aux_info_record PARAMS ((tree, int, int, int));
175 extern unsigned int min_precision PARAMS ((tree, int));
178 extern tree convert PARAMS ((tree, tree));
181 extern tree build_enumerator PARAMS ((tree, tree));
182 /* Add qualifiers to a type, in the fashion for C. */
183 extern tree c_build_qualified_type PARAMS ((tree, int));
184 #define c_build_type_variant(TYPE, CONST_P, VOLATILE_P) \
185 c_build_qualified_type (TYPE, \
186 ((CONST_P) ? TYPE_QUAL_CONST : 0) | \
187 ((VOLATILE_P) ? TYPE_QUAL_VOLATILE : 0))
188 extern int c_decode_option PARAMS ((int, char **));
189 extern void c_mark_varargs PARAMS ((void));
190 extern tree check_identifier PARAMS ((tree, tree));
191 extern void clear_parm_order PARAMS ((void));
192 extern tree combine_parm_decls PARAMS ((tree, tree, int));
193 extern int complete_array_type PARAMS ((tree, tree, int));
194 extern void declare_parm_level PARAMS ((int));
195 extern tree define_label PARAMS ((const char *, int,
197 extern void delete_block PARAMS ((tree));
198 extern void finish_decl PARAMS ((tree, tree, tree));
199 extern void finish_decl_top_level PARAMS ((tree, tree, tree));
200 extern tree finish_enum PARAMS ((tree, tree, tree));
201 extern void finish_function PARAMS ((int));
202 extern tree finish_struct PARAMS ((tree, tree, tree));
203 extern tree get_parm_info PARAMS ((int));
204 extern tree getdecls PARAMS ((void));
205 extern tree gettags PARAMS ((void));
206 extern int global_bindings_p PARAMS ((void));
207 extern tree grokfield PARAMS ((const char *, int, tree, tree, tree));
208 extern tree groktypename PARAMS ((tree));
209 extern tree groktypename_in_parm_context PARAMS ((tree));
210 extern tree implicitly_declare PARAMS ((tree));
211 extern int in_parm_level_p PARAMS ((void));
212 extern void init_decl_processing PARAMS ((void));
213 extern void insert_block PARAMS ((tree));
214 extern void keep_next_level PARAMS ((void));
215 extern int kept_level_p PARAMS ((void));
216 extern tree lookup_label PARAMS ((tree));
217 extern tree lookup_name PARAMS ((tree));
218 extern tree lookup_name_current_level PARAMS ((tree));
219 extern tree lookup_name_current_level_global PARAMS ((tree));
220 extern tree maybe_build_cleanup PARAMS ((tree));
221 extern void parmlist_tags_warning PARAMS ((void));
222 extern void pending_xref_error PARAMS ((void));
223 extern void mark_c_function_context PARAMS ((struct function *));
224 extern void push_c_function_context PARAMS ((struct function *));
225 extern void pop_c_function_context PARAMS ((struct function *));
226 extern void pop_label_level PARAMS ((void));
227 extern tree poplevel PARAMS ((int, int, int));
228 extern void print_lang_decl PARAMS ((FILE *, tree, int));
229 extern void print_lang_identifier PARAMS ((FILE *, tree, int));
230 extern void print_lang_type PARAMS ((FILE *, tree, int));
231 extern void push_label_level PARAMS ((void));
232 extern void push_parm_decl PARAMS ((tree));
233 extern tree pushdecl PARAMS ((tree));
234 extern tree pushdecl_top_level PARAMS ((tree));
235 extern void pushlevel PARAMS ((int));
236 extern void pushtag PARAMS ((tree, tree));
237 extern void set_block PARAMS ((tree));
238 extern tree shadow_label PARAMS ((tree));
239 extern void shadow_record_fields PARAMS ((tree));
240 extern void shadow_tag PARAMS ((tree));
241 extern void shadow_tag_warned PARAMS ((tree, int));
242 extern tree start_enum PARAMS ((tree));
243 extern int start_function PARAMS ((tree, tree, tree,
245 extern tree start_decl PARAMS ((tree, tree, int,
247 extern tree start_struct PARAMS ((enum tree_code, tree));
248 extern void store_parm_decls PARAMS ((void));
249 extern tree xref_tag PARAMS ((enum tree_code, tree));
252 extern tree require_complete_type PARAMS ((tree));
253 extern void incomplete_type_error PARAMS ((tree, tree));
254 /* Given two integer or real types, return the type for their sum.
255 Given two compatible ANSI C types, returns the merged type. */
256 extern tree common_type PARAMS ((tree, tree));
257 extern int comptypes PARAMS ((tree, tree));
258 extern tree c_sizeof PARAMS ((tree));
259 extern tree c_sizeof_nowarn PARAMS ((tree));
260 extern tree c_size_in_bytes PARAMS ((tree));
261 extern tree c_alignof PARAMS ((tree));
262 extern tree c_alignof_expr PARAMS ((tree));
263 extern tree default_conversion PARAMS ((tree));
264 extern tree build_component_ref PARAMS ((tree, tree));
265 extern tree build_indirect_ref PARAMS ((tree, const char *));
266 extern tree build_array_ref PARAMS ((tree, tree));
267 extern tree build_external_ref PARAMS ((tree, int));
268 extern tree build_function_call PARAMS ((tree, tree));
269 extern tree parser_build_binary_op PARAMS ((enum tree_code,
271 extern tree build_binary_op PARAMS ((enum tree_code,
273 extern tree build_unary_op PARAMS ((enum tree_code,
275 extern int lvalue_p PARAMS ((tree));
276 extern int lvalue_or_else PARAMS ((tree, const char *));
277 extern void readonly_warning PARAMS ((tree, const char *));
278 extern int mark_addressable PARAMS ((tree));
279 extern tree build_conditional_expr PARAMS ((tree, tree, tree));
280 extern tree build_compound_expr PARAMS ((tree));
281 extern tree build_c_cast PARAMS ((tree, tree));
282 extern tree build_modify_expr PARAMS ((tree, enum tree_code,
284 extern void store_init_value PARAMS ((tree, tree));
285 extern void error_init PARAMS ((const char *));
286 extern void pedwarn_init PARAMS ((const char *));
287 extern void start_init PARAMS ((tree, tree, int));
288 extern void finish_init PARAMS ((void));
289 extern void really_start_incremental_init PARAMS ((tree));
290 extern void push_init_level PARAMS ((int));
291 extern tree pop_init_level PARAMS ((int));
292 extern void set_init_index PARAMS ((tree, tree));
293 extern void set_init_label PARAMS ((tree));
294 extern void process_init_element PARAMS ((tree));
295 extern void c_expand_asm_operands PARAMS ((tree, tree, tree,
298 extern void c_expand_return PARAMS ((tree));
299 extern tree c_expand_start_case PARAMS ((tree));
300 extern void pedwarn_c99 PARAMS ((const char *, ...))
304 extern void init_iterators PARAMS ((void));
305 extern void iterator_expand PARAMS ((tree));
306 extern void iterator_for_loop_start PARAMS ((tree));
307 extern void iterator_for_loop_end PARAMS ((tree));
308 extern void iterator_for_loop_record PARAMS ((tree));
309 extern void push_iterator_stack PARAMS ((void));
310 extern void pop_iterator_stack PARAMS ((void));
312 /* Set to 0 at beginning of a function definition, set to 1 if
313 a return statement that specifies a return value is seen. */
315 extern int current_function_returns_value;
317 /* Set to 0 at beginning of a function definition, set to 1 if
318 a return statement with no argument is seen. */
320 extern int current_function_returns_null;
322 /* Nonzero means the expression being parsed will never be evaluated.
323 This is a count, since unevaluated expressions can nest. */
325 extern int skip_evaluation;
327 /* Nonzero means `$' can be in an identifier. */
329 extern int dollars_in_ident;
331 /* Nonzero means allow type mismatches in conditional expressions;
332 just make their values `void'. */
334 extern int flag_cond_mismatch;
336 /* Nonzero means don't recognize the keyword `asm'. */
338 extern int flag_no_asm;
340 /* Nonzero means environment is hosted (i.e., not freestanding) */
342 extern int flag_hosted;
344 /* Nonzero means warn about implicit declarations. */
346 extern int warn_implicit;
348 /* Nonzero means give string constants the type `const char *'
349 to get extra warnings from them. These warnings will be too numerous
350 to be useful, except in thoroughly ANSIfied programs. */
352 extern int flag_const_strings;
354 /* Nonzero means warn about sizeof (function) or addition/subtraction
355 of function pointers. */
357 extern int warn_pointer_arith;
359 /* Nonzero means warn for all old-style non-prototype function decls. */
361 extern int warn_strict_prototypes;
363 /* Nonzero means warn about multiple (redundant) decls for the same single
364 variable or function. */
366 extern int warn_redundant_decls;
368 /* Nonzero means warn about extern declarations of objects not at
369 file-scope level and about *all* declarations of functions (whether
370 extern or static) not at file-scope level. Note that we exclude
371 implicit function declarations. To get warnings about those, use
374 extern int warn_nested_externs;
376 /* Nonzero means warn about pointer casts that can drop a type qualifier
377 from the pointer target type. */
379 extern int warn_cast_qual;
381 /* Nonzero means warn when casting a function call to a type that does
382 not match the return type (e.g. (float)sqrt() or (anything*)malloc()
383 when there is no previous declaration of sqrt or malloc. */
385 extern int warn_bad_function_cast;
387 /* Warn about functions which might be candidates for attribute noreturn. */
389 extern int warn_missing_noreturn;
391 /* Warn about traditional constructs whose meanings changed in ANSI C. */
393 extern int warn_traditional;
395 /* Warn about *printf or *scanf format/argument anomalies. */
397 extern int warn_format;
399 /* Warn about a subscript that has type char. */
401 extern int warn_char_subscripts;
403 /* Warn if a type conversion is done that might have confusing results. */
405 extern int warn_conversion;
407 /* Warn if main is suspicious. */
409 extern int warn_main;
411 /* Nonzero means do some things the same way PCC does. */
413 extern int flag_traditional;
415 /* Nonzero means use the ISO C99 dialect of C. */
417 extern int flag_isoc99;
419 /* Nonzero means to allow single precision math even if we're generally
420 being traditional. */
421 extern int flag_allow_single_precision;
423 /* Nonzero means warn about suggesting putting in ()'s. */
425 extern int warn_parentheses;
427 /* Warn if initializer is not completely bracketed. */
429 extern int warn_missing_braces;
431 /* Warn about comparison of signed and unsigned values. */
433 extern int warn_sign_compare;
435 /* Warn about testing equality of floating point numbers. */
437 extern int warn_float_equal;
439 /* Warn about multicharacter constants. */
441 extern int warn_multichar;
443 /* Warn about long long. */
445 extern int warn_long_long;
447 /* Nonzero means we are reading code that came from a system header file. */
449 extern int system_header_p;
451 /* Nonzero enables objc features. */
453 #define doing_objc_thang \
454 (c_language == clk_objective_c)
457 extern void finish_incomplete_decl PARAMS ((tree));
459 #endif /* not _C_TREE_H */