1 /* Definitions for C parsing and type checking.
2 Copyright (C) 1987, 1993, 1994, 1995 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 /* Nonzero if the type T promotes to itself.
128 ANSI C states explicitly the list of types that promote;
129 in particular, short promotes to int even if they have the same width. */
130 #define C_PROMOTING_INTEGER_TYPE_P(t) \
131 (TREE_CODE ((t)) == INTEGER_TYPE \
132 && (TYPE_MAIN_VARIANT (t) == char_type_node \
133 || TYPE_MAIN_VARIANT (t) == signed_char_type_node \
134 || TYPE_MAIN_VARIANT (t) == unsigned_char_type_node \
135 || TYPE_MAIN_VARIANT (t) == short_integer_type_node \
136 || TYPE_MAIN_VARIANT (t) == short_unsigned_type_node))
138 /* In a VAR_DECL, means the variable is really an iterator. */
139 #define ITERATOR_P(D) (DECL_LANG_FLAG_4(D))
141 /* In a VAR_DECL for an iterator, means we are within
142 an explicit loop over that iterator. */
143 #define ITERATOR_BOUND_P(NODE) ((NODE)->common.readonly_flag)
145 /* in c-lang.c and objc-act.c */
146 extern tree lookup_interface PROTO((tree));
147 extern tree is_class_name PROTO((tree));
148 extern void maybe_objc_check_decl PROTO((tree));
149 extern int maybe_objc_comptypes PROTO((tree, tree, int));
150 extern tree maybe_building_objc_message_expr PROTO((void));
151 extern tree maybe_objc_method_name PROTO((tree));
152 extern int recognize_objc_keyword PROTO((void));
153 extern tree build_objc_string PROTO((int, char *));
155 /* in c-aux-info.c */
156 extern void gen_aux_info_record PROTO((tree, int, int, int));
159 extern void declare_function_name PROTO((void));
160 extern void decl_attributes PROTO((tree, tree, tree));
161 extern void init_function_format_info PROTO((void));
162 extern void record_function_format PROTO((tree, tree, int, int, int, int));
163 extern void check_function_format PROTO((tree, tree, tree));
164 /* Print an error message for invalid operands to arith operation CODE.
165 NOP_EXPR is used as a special case (see truthvalue_conversion). */
166 extern void binary_op_error PROTO((enum tree_code));
167 extern void c_expand_expr_stmt PROTO((tree));
168 /* Validate the expression after `case' and apply default promotions. */
169 extern tree check_case_value PROTO((tree));
170 /* Concatenate a list of STRING_CST nodes into one STRING_CST. */
171 extern tree combine_strings PROTO((tree));
172 extern void constant_expression_warning PROTO((tree));
173 extern tree convert_and_check PROTO((tree, tree));
174 extern void overflow_warning PROTO((tree));
175 extern void unsigned_conversion_warning PROTO((tree, tree));
176 /* Read the rest of the current #-directive line. */
177 extern char *get_directive_line STDIO_PROTO((FILE *));
178 /* Subroutine of build_binary_op, used for comparison operations.
179 See if the operands have both been converted from subword integer types
180 and, if so, perhaps change them both back to their original type. */
181 extern tree shorten_compare PROTO((tree *, tree *, tree *, enum tree_code *));
182 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
183 or validate its data type for an `if' or `while' statement or ?..: exp. */
184 extern tree truthvalue_conversion PROTO((tree));
185 extern tree type_for_mode PROTO((enum machine_mode, int));
186 extern tree type_for_size PROTO((unsigned, int));
189 extern tree convert PROTO((tree, tree));
192 /* Standard named or nameless data types of the C compiler. */
193 extern tree char_array_type_node;
194 extern tree char_type_node;
195 extern tree const_ptr_type_node;
196 extern tree const_string_type_node;
197 extern tree default_function_type;
198 extern tree double_ftype_double;
199 extern tree double_ftype_double_double;
200 extern tree double_type_node;
201 extern tree float_type_node;
202 extern tree intDI_type_node;
203 extern tree intHI_type_node;
204 extern tree intQI_type_node;
205 extern tree intSI_type_node;
206 extern tree int_array_type_node;
207 extern tree int_ftype_cptr_cptr_sizet;
208 extern tree int_ftype_int;
209 extern tree int_ftype_ptr_ptr_int;
210 extern tree int_ftype_string_string;
211 extern tree integer_type_node;
212 extern tree long_double_type_node;
213 extern tree long_ftype_long;
214 extern tree long_integer_type_node;
215 extern tree long_long_integer_type_node;
216 extern tree long_long_unsigned_type_node;
217 extern tree long_unsigned_type_node;
218 extern tree complex_integer_type_node;
219 extern tree complex_float_type_node;
220 extern tree complex_double_type_node;
221 extern tree complex_long_double_type_node;
222 extern tree ptr_type_node;
223 extern tree ptrdiff_type_node;
224 extern tree short_integer_type_node;
225 extern tree short_unsigned_type_node;
226 extern tree signed_char_type_node;
227 extern tree signed_wchar_type_node;
228 extern tree string_ftype_ptr_ptr;
229 extern tree string_type_node;
230 extern tree unsigned_char_type_node;
231 extern tree unsigned_intDI_type_node;
232 extern tree unsigned_intHI_type_node;
233 extern tree unsigned_intQI_type_node;
234 extern tree unsigned_intSI_type_node;
235 extern tree unsigned_type_node;
236 extern tree unsigned_wchar_type_node;
237 extern tree void_ftype_ptr_int_int;
238 extern tree void_ftype_ptr_ptr_int;
239 extern tree void_type_node;
240 extern tree wchar_array_type_node;
241 extern tree wchar_type_node;
242 extern tree boolean_type_node;
243 extern tree boolean_true_node;
244 extern tree boolean_false_node;
246 extern tree build_enumerator PROTO((tree, tree));
247 /* Declare a predefined function. Return the declaration. */
248 extern tree builtin_function PROTO((char *, tree, enum built_in_function function_, char *));
249 /* Add qualifiers to a type, in the fashion for C. */
250 extern tree c_build_type_variant PROTO((tree, int, int));
251 extern int c_decode_option PROTO((char *));
252 extern void c_mark_varargs PROTO((void));
253 extern tree check_identifier PROTO((tree, tree));
254 extern void clear_parm_order PROTO((void));
255 extern tree combine_parm_decls PROTO((tree, tree, int));
256 extern int complete_array_type PROTO((tree, tree, int));
257 extern void declare_parm_level PROTO((int));
258 extern tree define_label PROTO((char *, int, tree));
259 extern void delete_block PROTO((tree));
260 extern void finish_decl PROTO((tree, tree, tree));
261 extern void finish_decl_top_level PROTO((tree, tree, tree));
262 extern tree finish_enum PROTO((tree, tree, tree));
263 extern void finish_function PROTO((int));
264 extern tree finish_struct PROTO((tree, tree, tree));
265 extern tree get_parm_info PROTO((int));
266 extern tree getdecls PROTO((void));
267 extern tree gettags PROTO((void));
268 extern int global_bindings_p PROTO((void));
269 extern tree grokfield PROTO((char *, int, tree, tree, tree));
270 extern tree groktypename PROTO((tree));
271 extern tree groktypename_in_parm_context PROTO((tree));
272 extern tree implicitly_declare PROTO((tree));
273 extern int in_parm_level_p PROTO((void));
274 extern void init_decl_processing PROTO((void));
275 extern void insert_block PROTO((tree));
276 extern void keep_next_level PROTO((void));
277 extern int kept_level_p PROTO((void));
278 extern tree lookup_label PROTO((tree));
279 extern tree lookup_name PROTO((tree));
280 extern tree lookup_name_current_level PROTO((tree));
281 extern tree lookup_name_current_level_global PROTO((tree));
282 extern tree maybe_build_cleanup PROTO((tree));
283 extern void parmlist_tags_warning PROTO((void));
284 extern void pending_xref_error PROTO((void));
285 extern void pop_c_function_context PROTO((void));
286 extern void pop_label_level PROTO((void));
287 extern tree poplevel PROTO((int, int, int));
288 extern void print_lang_decl STDIO_PROTO((FILE *, tree,
290 extern void print_lang_identifier STDIO_PROTO((FILE *, tree,
292 extern void print_lang_type STDIO_PROTO((FILE *, tree,
294 extern void push_c_function_context PROTO((void));
295 extern void push_label_level PROTO((void));
296 extern void push_parm_decl PROTO((tree));
297 extern tree pushdecl PROTO((tree));
298 extern tree pushdecl_top_level PROTO((tree));
299 extern void pushlevel PROTO((int));
300 extern void pushtag PROTO((tree, tree));
301 extern void set_block PROTO((tree));
302 extern tree shadow_label PROTO((tree));
303 extern void shadow_record_fields PROTO((tree));
304 extern void shadow_tag PROTO((tree));
305 extern void shadow_tag_warned PROTO((tree, int));
306 extern tree start_enum PROTO((tree));
307 extern int start_function PROTO((tree, tree, tree,
309 extern tree start_decl PROTO((tree, tree, int,
311 extern tree start_struct PROTO((enum tree_code, tree));
312 extern void store_parm_decls PROTO((void));
313 extern tree xref_tag PROTO((enum tree_code, tree));
316 extern tree require_complete_type PROTO((tree));
317 extern void incomplete_type_error PROTO((tree, tree));
318 /* Given two integer or real types, return the type for their sum.
319 Given two compatible ANSI C types, returns the merged type. */
320 extern tree common_type PROTO((tree, tree));
321 extern int comptypes PROTO((tree, tree));
322 extern int self_promoting_args_p PROTO((tree));
323 extern tree c_sizeof PROTO((tree));
324 extern tree c_sizeof_nowarn PROTO((tree));
325 extern tree c_size_in_bytes PROTO((tree));
326 extern tree c_alignof PROTO((tree));
327 extern tree c_alignof_expr PROTO((tree));
328 extern tree default_conversion PROTO((tree));
329 extern tree build_component_ref PROTO((tree, tree));
330 extern tree build_indirect_ref PROTO((tree, char *));
331 extern tree build_array_ref PROTO((tree, tree));
332 extern tree build_function_call PROTO((tree, tree));
333 extern tree parser_build_binary_op PROTO((enum tree_code,
335 extern tree build_binary_op PROTO((enum tree_code,
337 extern tree build_unary_op PROTO((enum tree_code,
339 extern int lvalue_p PROTO((tree));
340 extern int lvalue_or_else PROTO((tree, char *));
341 extern void readonly_warning PROTO((tree, char *));
342 extern int mark_addressable PROTO((tree));
343 extern tree build_conditional_expr PROTO((tree, tree, tree));
344 extern tree build_compound_expr PROTO((tree));
345 extern tree build_c_cast PROTO((tree, tree));
346 extern tree build_modify_expr PROTO((tree, enum tree_code,
348 extern tree initializer_constant_valid_p PROTO((tree, tree));
349 extern void store_init_value PROTO((tree, tree));
350 extern void error_init PROTO((char *, char *,
352 extern void pedwarn_init PROTO((char *, char *,
354 extern void start_init PROTO((tree, tree, int));
355 extern void finish_init PROTO((void));
356 extern void really_start_incremental_init PROTO((tree));
357 extern void push_init_level PROTO((int));
358 extern tree pop_init_level PROTO((int));
359 extern void set_init_index PROTO((tree, tree));
360 extern void set_init_label PROTO((tree));
361 extern void process_init_element PROTO((tree));
362 extern void c_expand_asm_operands PROTO((tree, tree, tree, tree,
364 extern void c_expand_return PROTO((tree));
365 extern tree c_expand_start_case PROTO((tree));
368 extern void iterator_expand PROTO((tree));
369 extern void iterator_for_loop_start PROTO((tree));
370 extern void iterator_for_loop_end PROTO((tree));
371 extern void iterator_for_loop_record PROTO((tree));
372 extern void push_iterator_stack PROTO((void));
373 extern void pop_iterator_stack PROTO((void));
375 /* Set to 0 at beginning of a function definition, set to 1 if
376 a return statement that specifies a return value is seen. */
378 extern int current_function_returns_value;
380 /* Set to 0 at beginning of a function definition, set to 1 if
381 a return statement with no argument is seen. */
383 extern int current_function_returns_null;
385 /* Nonzero means `$' can be in an identifier. */
387 extern int dollars_in_ident;
389 /* Nonzero means allow type mismatches in conditional expressions;
390 just make their values `void'. */
392 extern int flag_cond_mismatch;
394 /* Nonzero means don't recognize the keyword `asm'. */
396 extern int flag_no_asm;
398 /* Nonzero means ignore `#ident' directives. */
400 extern int flag_no_ident;
402 /* Nonzero means warn about implicit declarations. */
404 extern int warn_implicit;
406 /* Nonzero means give string constants the type `const char *'
407 to get extra warnings from them. These warnings will be too numerous
408 to be useful, except in thoroughly ANSIfied programs. */
410 extern int warn_write_strings;
412 /* Nonzero means warn about sizeof (function) or addition/subtraction
413 of function pointers. */
415 extern int warn_pointer_arith;
417 /* Nonzero means warn for all old-style non-prototype function decls. */
419 extern int warn_strict_prototypes;
421 /* Nonzero means warn about multiple (redundant) decls for the same single
422 variable or function. */
424 extern int warn_redundant_decls;
426 /* Nonzero means warn about extern declarations of objects not at
427 file-scope level and about *all* declarations of functions (whether
428 extern or static) not at file-scope level. Note that we exclude
429 implicit function declarations. To get warnings about those, use
432 extern int warn_nested_externs;
434 /* Nonzero means warn about pointer casts that can drop a type qualifier
435 from the pointer target type. */
437 extern int warn_cast_qual;
439 /* Nonzero means warn when casting a function call to a type that does
440 not match the return type (e.g. (float)sqrt() or (anything*)malloc()
441 when there is no previous declaration of sqrt or malloc. */
443 extern int warn_bad_function_cast;
445 /* Warn about traditional constructs whose meanings changed in ANSI C. */
447 extern int warn_traditional;
449 /* Warn about *printf or *scanf format/argument anomalies. */
451 extern int warn_format;
453 /* Warn about a subscript that has type char. */
455 extern int warn_char_subscripts;
457 /* Warn if a type conversion is done that might have confusing results. */
459 extern int warn_conversion;
461 /* Nonzero means do some things the same way PCC does. */
463 extern int flag_traditional;
465 /* Nonzero means to allow single precision math even if we're generally
466 being traditional. */
467 extern int flag_allow_single_precision;
469 /* Nonzero means warn about suggesting putting in ()'s. */
471 extern int warn_parentheses;
473 /* Warn if initializer is not completely bracketed. */
475 extern int warn_missing_braces;
477 /* Nonzero means this is a function to call to perform comptypes
478 on two record types. */
480 extern int (*comptypes_record_hook) ();
482 /* Nonzero means we are reading code that came from a system header file. */
484 extern int system_header_p;
486 /* Nonzero enables objc features. */
488 extern int doing_objc_thang;
490 #endif /* not _C_TREE_H */