1 /* Definitions for C parsing and type checking.
2 Copyright (C) 1987, 93, 94, 95, 97, 98, 1999 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 /* C types are partitioned into three subsets: object, function, and
85 #define C_TYPE_OBJECT_P(type) \
86 (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type))
88 #define C_TYPE_FUNCTION_P(type) \
89 (TREE_CODE (type) == FUNCTION_TYPE)
91 #define C_TYPE_INCOMPLETE_P(type) \
92 (TREE_CODE (type) != FUNCTION_TYPE && TYPE_SIZE (type) == 0)
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))
99 /* In a RECORD_TYPE, a sorted array of the fields of the type. */
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)
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)
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))
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)
126 /* Store a value in that field. */
127 #define C_SET_EXP_ORIGINAL_CODE(exp, code) \
128 (TREE_COMPLEXITY (exp) = (int) (code))
130 /* Record whether a typedef for type `int' was actually `signed int'. */
131 #define C_TYPEDEF_EXPLICITLY_SIGNED(exp) DECL_LANG_FLAG_1 ((exp))
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))
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)
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)
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))
157 /* In a VAR_DECL, means the variable is really an iterator. */
158 #define ITERATOR_P(D) (DECL_LANG_FLAG_4(D))
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)
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, const char *));
175 /* in c-aux-info.c */
176 extern void gen_aux_info_record
PROTO((tree
, int, int, int));
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. */
202 extern char *get_directive_line
PROTO((void));
203 #define GET_DIRECTIVE_LINE() get_directive_line ()
205 extern char *get_directive_line
PROTO((FILE *));
206 #define GET_DIRECTIVE_LINE() get_directive_line (finput)
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));
220 extern tree convert
PROTO((tree
, tree
));
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
;
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
;
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
;
283 extern tree build_enumerator
PROTO((tree
, tree
));
284 /* Declare a predefined function. Return the declaration. */
285 extern tree builtin_function
PROTO((const char *, tree
, enum built_in_function function_
, const 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((const 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
,
347 extern tree start_decl
PROTO((tree
, tree
, int,
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
));
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
, const 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
,
373 extern tree build_binary_op
PROTO((enum tree_code
,
375 extern tree build_unary_op
PROTO((enum tree_code
,
377 extern int lvalue_p
PROTO((tree
));
378 extern int lvalue_or_else
PROTO((tree
, const char *));
379 extern void readonly_warning
PROTO((tree
, const 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
,
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((const char *));
389 extern void pedwarn_init
PROTO((const 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
,
400 extern void c_expand_return
PROTO((tree
));
401 extern tree c_expand_start_case
PROTO((tree
));
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));
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. */
415 extern int current_function_returns_value
;
417 /* Set to 0 at beginning of a function definition, set to 1 if
418 a return statement with no argument is seen. */
420 extern int current_function_returns_null
;
422 /* Nonzero means the expression being parsed will never be evaluated.
423 This is a count, since unevaluated expressions can nest. */
425 extern int skip_evaluation
;
427 /* Nonzero means `$' can be in an identifier. */
429 extern int dollars_in_ident
;
431 /* Nonzero means allow type mismatches in conditional expressions;
432 just make their values `void'. */
434 extern int flag_cond_mismatch
;
436 /* Nonzero means don't recognize the keyword `asm'. */
438 extern int flag_no_asm
;
440 /* Nonzero means environment is hosted (i.e., not freestanding) */
442 extern int flag_hosted
;
444 /* Nonzero means warn about implicit declarations. */
446 extern int warn_implicit
;
448 /* Nonzero means give string constants the type `const char *'
449 to get extra warnings from them. These warnings will be too numerous
450 to be useful, except in thoroughly ANSIfied programs. */
452 extern int flag_const_strings
;
454 /* Nonzero means warn about sizeof (function) or addition/subtraction
455 of function pointers. */
457 extern int warn_pointer_arith
;
459 /* Nonzero means warn for all old-style non-prototype function decls. */
461 extern int warn_strict_prototypes
;
463 /* Nonzero means warn about multiple (redundant) decls for the same single
464 variable or function. */
466 extern int warn_redundant_decls
;
468 /* Nonzero means warn about extern declarations of objects not at
469 file-scope level and about *all* declarations of functions (whether
470 extern or static) not at file-scope level. Note that we exclude
471 implicit function declarations. To get warnings about those, use
474 extern int warn_nested_externs
;
476 /* Nonzero means warn about pointer casts that can drop a type qualifier
477 from the pointer target type. */
479 extern int warn_cast_qual
;
481 /* Nonzero means warn when casting a function call to a type that does
482 not match the return type (e.g. (float)sqrt() or (anything*)malloc()
483 when there is no previous declaration of sqrt or malloc. */
485 extern int warn_bad_function_cast
;
487 /* Warn about functions which might be candidates for attribute noreturn. */
489 extern int warn_missing_noreturn
;
491 /* Warn about traditional constructs whose meanings changed in ANSI C. */
493 extern int warn_traditional
;
495 /* Warn about *printf or *scanf format/argument anomalies. */
497 extern int warn_format
;
499 /* Warn about a subscript that has type char. */
501 extern int warn_char_subscripts
;
503 /* Warn if a type conversion is done that might have confusing results. */
505 extern int warn_conversion
;
507 /* Warn if main is suspicious. */
509 extern int warn_main
;
511 /* Nonzero means do some things the same way PCC does. */
513 extern int flag_traditional
;
515 /* Nonzero means use the ISO C9x dialect of C. */
517 extern int flag_isoc9x
;
519 /* Nonzero means to allow single precision math even if we're generally
520 being traditional. */
521 extern int flag_allow_single_precision
;
523 /* Nonzero means warn about suggesting putting in ()'s. */
525 extern int warn_parentheses
;
527 /* Warn if initializer is not completely bracketed. */
529 extern int warn_missing_braces
;
531 /* Warn about comparison of signed and unsigned values. */
533 extern int warn_sign_compare
;
535 /* Warn about multicharacter constants. */
537 extern int warn_multichar
;
539 /* Warn about long long. */
541 extern int warn_long_long
;
543 /* Nonzero means we are reading code that came from a system header file. */
545 extern int system_header_p
;
547 /* Nonzero enables objc features. */
549 extern int doing_objc_thang
;
552 extern void finish_incomplete_decl
PROTO((tree
));
554 #endif /* not _C_TREE_H */