c-tree.h revision 50453
1/* Definitions for C parsing and type checking.
2   Copyright (C) 1987, 1993, 1994, 1995, 1997 Free Software Foundation, Inc.
3
4This file is part of GNU CC.
5
6GNU CC is free software; you can redistribute it and/or modify
7it under the terms of the GNU General Public License as published by
8the Free Software Foundation; either version 2, or (at your option)
9any later version.
10
11GNU CC is distributed in the hope that it will be useful,
12but WITHOUT ANY WARRANTY; without even the implied warranty of
13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14GNU General Public License for more details.
15
16You should have received a copy of the GNU General Public License
17along with GNU CC; see the file COPYING.  If not, write to
18the Free Software Foundation, 59 Temple Place - Suite 330,
19Boston, 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
30struct 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.  */
71extern 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/* In a RECORD_TYPE, a sorted array of the fields of the type.  */
84struct lang_type
85{
86  int len;
87  tree elts[1];
88};
89
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)
93
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)
98
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))
102
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)
108#endif
109
110/* Store a value in that field.  */
111#define C_SET_EXP_ORIGINAL_CODE(exp, code) \
112  (TREE_COMPLEXITY (exp) = (int) (code))
113
114/* Record whether a typedef for type `int' was actually `signed int'.  */
115#define C_TYPEDEF_EXPLICITLY_SIGNED(exp) DECL_LANG_FLAG_1 ((exp))
116
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))
121
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)
126
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)
129
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))
140
141/* In a VAR_DECL, means the variable is really an iterator.  */
142#define ITERATOR_P(D) (DECL_LANG_FLAG_4(D))
143
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)
147
148/* in c-lang.c and objc-act.c */
149extern tree lookup_interface			PROTO((tree));
150extern tree is_class_name			PROTO((tree));
151extern void maybe_objc_check_decl		PROTO((tree));
152extern void finish_file				PROTO((void));
153extern int maybe_objc_comptypes                 PROTO((tree, tree, int));
154extern tree maybe_building_objc_message_expr    PROTO((void));
155extern tree maybe_objc_method_name		PROTO((tree));
156extern int recognize_objc_keyword		PROTO((void));
157extern tree build_objc_string			PROTO((int, char *));
158
159/* in c-aux-info.c */
160extern void gen_aux_info_record                 PROTO((tree, int, int, int));
161
162/* in c-common.c */
163extern void declare_function_name               PROTO((void));
164extern void decl_attributes                     PROTO((tree, tree, tree));
165extern void init_function_format_info		PROTO((void));
166extern void check_function_format		PROTO((tree, tree, tree));
167extern 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).  */
170extern void binary_op_error                     PROTO((enum tree_code));
171extern void c_expand_expr_stmt                  PROTO((tree));
172extern void c_expand_start_cond                 PROTO((tree, int, int));
173extern void c_expand_start_else                 PROTO((void));
174extern void c_expand_end_cond                   PROTO((void));
175/* Validate the expression after `case' and apply default promotions.  */
176extern tree check_case_value                    PROTO((tree));
177/* Concatenate a list of STRING_CST nodes into one STRING_CST.  */
178extern tree combine_strings                     PROTO((tree));
179extern void constant_expression_warning         PROTO((tree));
180extern tree convert_and_check			PROTO((tree, tree));
181extern void overflow_warning			PROTO((tree));
182extern void unsigned_conversion_warning		PROTO((tree, tree));
183/* Read the rest of the current #-directive line.  */
184#if USE_CPPLIB
185extern char *get_directive_line                 PROTO((void));
186#define GET_DIRECTIVE_LINE() get_directive_line ()
187#else
188extern char *get_directive_line                 PROTO((FILE *));
189#define GET_DIRECTIVE_LINE() get_directive_line (finput)
190#endif
191
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.  */
195extern 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. */
198extern tree truthvalue_conversion               PROTO((tree));
199extern tree type_for_mode                       PROTO((enum machine_mode, int));
200extern tree type_for_size                       PROTO((unsigned, int));
201
202/* in c-convert.c */
203extern tree convert                             PROTO((tree, tree));
204
205/* in c-decl.c */
206/* Standard named or nameless data types of the C compiler.  */
207extern tree char_array_type_node;
208extern tree char_type_node;
209extern tree const_ptr_type_node;
210extern tree const_string_type_node;
211extern tree default_function_type;
212extern tree double_ftype_double;
213extern tree double_ftype_double_double;
214extern tree double_type_node;
215extern tree float_type_node;
216extern tree intTI_type_node;
217extern tree intDI_type_node;
218extern tree intHI_type_node;
219extern tree intQI_type_node;
220extern tree intSI_type_node;
221extern tree int_array_type_node;
222extern tree int_ftype_cptr_cptr_sizet;
223extern tree int_ftype_int;
224extern tree int_ftype_ptr_ptr_int;
225extern tree int_ftype_string_string;
226extern tree integer_type_node;
227extern tree long_double_type_node;
228extern tree long_ftype_long;
229extern tree long_integer_type_node;
230extern tree long_long_integer_type_node;
231extern tree long_long_unsigned_type_node;
232extern tree long_unsigned_type_node;
233extern tree complex_integer_type_node;
234extern tree complex_float_type_node;
235extern tree complex_double_type_node;
236extern tree complex_long_double_type_node;
237extern tree ptr_type_node;
238extern tree ptrdiff_type_node;
239extern tree short_integer_type_node;
240extern tree short_unsigned_type_node;
241extern tree signed_char_type_node;
242extern tree signed_wchar_type_node;
243extern tree string_ftype_ptr_ptr;
244extern tree string_type_node;
245extern tree unsigned_char_type_node;
246extern tree unsigned_intTI_type_node;
247extern tree unsigned_intDI_type_node;
248extern tree unsigned_intHI_type_node;
249extern tree unsigned_intQI_type_node;
250extern tree unsigned_intSI_type_node;
251extern tree unsigned_type_node;
252extern tree unsigned_wchar_type_node;
253extern tree void_ftype_ptr_int_int;
254extern tree void_ftype_ptr_ptr_int;
255extern tree void_type_node;
256extern tree wchar_array_type_node;
257extern tree wchar_type_node;
258extern tree boolean_type_node;
259extern tree boolean_true_node;
260extern tree boolean_false_node;
261
262extern tree build_enumerator                    PROTO((tree, tree));
263/* Declare a predefined function.  Return the declaration.  */
264extern tree builtin_function                    PROTO((char *, tree, enum built_in_function function_, char *));
265/* Add qualifiers to a type, in the fashion for C.  */
266extern tree c_build_type_variant                PROTO((tree, int, int));
267extern int  c_decode_option                     PROTO((int, char **));
268extern void c_mark_varargs                      PROTO((void));
269extern tree check_identifier                    PROTO((tree, tree));
270extern void clear_parm_order                    PROTO((void));
271extern tree combine_parm_decls                  PROTO((tree, tree, int));
272extern int  complete_array_type                 PROTO((tree, tree, int));
273extern void declare_parm_level                  PROTO((int));
274extern tree define_label                        PROTO((char *, int, tree));
275extern void delete_block                        PROTO((tree));
276extern void finish_decl                         PROTO((tree, tree, tree));
277extern void finish_decl_top_level               PROTO((tree, tree, tree));
278extern tree finish_enum                         PROTO((tree, tree, tree));
279extern void finish_function                     PROTO((int));
280extern tree finish_struct                       PROTO((tree, tree, tree));
281extern tree get_parm_info                       PROTO((int));
282extern tree getdecls                            PROTO((void));
283extern tree gettags                             PROTO((void));
284extern int  global_bindings_p                   PROTO((void));
285extern tree grokfield                           PROTO((char *, int, tree, tree, tree));
286extern tree groktypename                        PROTO((tree));
287extern tree groktypename_in_parm_context        PROTO((tree));
288extern tree implicitly_declare                  PROTO((tree));
289extern int  in_parm_level_p                     PROTO((void));
290extern void init_decl_processing                PROTO((void));
291extern void insert_block                        PROTO((tree));
292extern void keep_next_level                     PROTO((void));
293extern int  kept_level_p                        PROTO((void));
294extern tree lookup_label                        PROTO((tree));
295extern tree lookup_name                         PROTO((tree));
296extern tree lookup_name_current_level		PROTO((tree));
297extern tree lookup_name_current_level_global	PROTO((tree));
298extern tree maybe_build_cleanup                 PROTO((tree));
299extern void parmlist_tags_warning               PROTO((void));
300extern void pending_xref_error                  PROTO((void));
301extern void pop_c_function_context              PROTO((void));
302extern void pop_label_level                     PROTO((void));
303extern tree poplevel                            PROTO((int, int, int));
304extern void print_lang_decl                     PROTO((FILE *, tree, int));
305extern void print_lang_identifier               PROTO((FILE *, tree, int));
306extern void print_lang_type                     PROTO((FILE *, tree, int));
307extern void push_c_function_context             PROTO((void));
308extern void push_label_level                    PROTO((void));
309extern void push_parm_decl                      PROTO((tree));
310extern tree pushdecl                            PROTO((tree));
311extern tree pushdecl_top_level                  PROTO((tree));
312extern void pushlevel                           PROTO((int));
313extern void pushtag                             PROTO((tree, tree));
314extern void set_block                           PROTO((tree));
315extern tree shadow_label                        PROTO((tree));
316extern void shadow_record_fields                PROTO((tree));
317extern void shadow_tag                          PROTO((tree));
318extern void shadow_tag_warned                   PROTO((tree, int));
319extern tree start_enum                          PROTO((tree));
320extern int  start_function                      PROTO((tree, tree, tree,
321						       tree, int));
322extern tree start_decl                          PROTO((tree, tree, int,
323						       tree, tree));
324extern tree start_struct                        PROTO((enum tree_code, tree));
325extern void store_parm_decls                    PROTO((void));
326extern tree xref_tag                            PROTO((enum tree_code, tree));
327
328/* in c-typeck.c */
329extern tree require_complete_type		PROTO((tree));
330extern void incomplete_type_error		PROTO((tree, tree));
331/* Given two integer or real types, return the type for their sum.
332   Given two compatible ANSI C types, returns the merged type.  */
333extern tree common_type                         PROTO((tree, tree));
334extern int comptypes				PROTO((tree, tree));
335extern int self_promoting_args_p		PROTO((tree));
336extern tree c_sizeof                            PROTO((tree));
337extern tree c_sizeof_nowarn                     PROTO((tree));
338extern tree c_size_in_bytes                     PROTO((tree));
339extern tree c_alignof				PROTO((tree));
340extern tree c_alignof_expr			PROTO((tree));
341extern tree default_conversion                  PROTO((tree));
342extern tree build_component_ref                 PROTO((tree, tree));
343extern tree build_indirect_ref                  PROTO((tree, char *));
344extern tree build_array_ref                     PROTO((tree, tree));
345extern tree build_function_call                 PROTO((tree, tree));
346extern tree parser_build_binary_op              PROTO((enum tree_code,
347						       tree, tree));
348extern tree build_binary_op                     PROTO((enum tree_code,
349						       tree, tree, int));
350extern tree build_unary_op                      PROTO((enum tree_code,
351						       tree, int));
352extern int lvalue_p				PROTO((tree));
353extern int lvalue_or_else			PROTO((tree, char *));
354extern void readonly_warning			PROTO((tree, char *));
355extern int mark_addressable			PROTO((tree));
356extern tree build_conditional_expr              PROTO((tree, tree, tree));
357extern tree build_compound_expr                 PROTO((tree));
358extern tree build_c_cast                        PROTO((tree, tree));
359extern tree build_modify_expr                   PROTO((tree, enum tree_code,
360						       tree));
361extern tree initializer_constant_valid_p	PROTO((tree, tree));
362extern void store_init_value                    PROTO((tree, tree));
363extern void error_init				PROTO((char *, char *,
364						       char *));
365extern void pedwarn_init			PROTO((char *, char *,
366						       char *));
367extern void start_init				PROTO((tree, tree, int));
368extern void finish_init				PROTO((void));
369extern void really_start_incremental_init	PROTO((tree));
370extern void push_init_level			PROTO((int));
371extern tree pop_init_level			PROTO((int));
372extern void set_init_index			PROTO((tree, tree));
373extern void set_init_label			PROTO((tree));
374extern void process_init_element		PROTO((tree));
375extern void c_expand_asm_operands		PROTO((tree, tree, tree, tree,
376						       int, char *, int));
377extern void c_expand_return			PROTO((tree));
378extern tree c_expand_start_case                 PROTO((tree));
379
380/* in c-iterate.c */
381extern void init_iterators			PROTO((void));
382extern void iterator_expand			PROTO((tree));
383extern void iterator_for_loop_start		PROTO((tree));
384extern void iterator_for_loop_end		PROTO((tree));
385extern void iterator_for_loop_record		PROTO((tree));
386extern void push_iterator_stack			PROTO((void));
387extern void pop_iterator_stack			PROTO((void));
388
389/* Set to 0 at beginning of a function definition, set to 1 if
390   a return statement that specifies a return value is seen.  */
391
392extern int current_function_returns_value;
393
394/* Set to 0 at beginning of a function definition, set to 1 if
395   a return statement with no argument is seen.  */
396
397extern int current_function_returns_null;
398
399/* Nonzero means the expression being parsed will never be evaluated.
400   This is a count, since unevaluated expressions can nest.  */
401
402extern int skip_evaluation;
403
404/* Nonzero means `$' can be in an identifier.  */
405
406extern int dollars_in_ident;
407
408/* Nonzero means allow type mismatches in conditional expressions;
409   just make their values `void'.   */
410
411extern int flag_cond_mismatch;
412
413/* Nonzero means don't recognize the keyword `asm'.  */
414
415extern int flag_no_asm;
416
417/* Nonzero means environment is hosted (i.e., not freestanding) */
418
419extern int flag_hosted;
420
421/* Nonzero means ignore `#ident' directives.  */
422
423extern int flag_no_ident;
424
425/* Nonzero means warn about implicit declarations.  */
426
427extern int warn_implicit;
428
429/* Nonzero means give string constants the type `const char *'
430   to get extra warnings from them.  These warnings will be too numerous
431   to be useful, except in thoroughly ANSIfied programs.  */
432
433extern int warn_write_strings;
434
435/* Nonzero means warn about sizeof (function) or addition/subtraction
436   of function pointers.  */
437
438extern int warn_pointer_arith;
439
440/* Nonzero means warn for all old-style non-prototype function decls.  */
441
442extern int warn_strict_prototypes;
443
444/* Nonzero means warn about multiple (redundant) decls for the same single
445   variable or function.  */
446
447extern int warn_redundant_decls;
448
449/* Nonzero means warn about extern declarations of objects not at
450   file-scope level and about *all* declarations of functions (whether
451   extern or static) not at file-scope level.  Note that we exclude
452   implicit function declarations.  To get warnings about those, use
453   -Wimplicit.  */
454
455extern int warn_nested_externs;
456
457/* Nonzero means warn about pointer casts that can drop a type qualifier
458   from the pointer target type.  */
459
460extern int warn_cast_qual;
461
462/* Nonzero means warn when casting a function call to a type that does
463   not match the return type (e.g. (float)sqrt() or (anything*)malloc()
464   when there is no previous declaration of sqrt or malloc.  */
465
466extern int warn_bad_function_cast;
467
468/* Warn about traditional constructs whose meanings changed in ANSI C.  */
469
470extern int warn_traditional;
471
472/* Warn about *printf or *scanf format/argument anomalies. */
473
474extern int warn_format;
475
476/* Warn about a subscript that has type char.  */
477
478extern int warn_char_subscripts;
479
480/* Warn if a type conversion is done that might have confusing results.  */
481
482extern int warn_conversion;
483
484/* Warn if main is suspicious. */
485
486extern int warn_main;
487
488/* Nonzero means do some things the same way PCC does.  */
489
490extern int flag_traditional;
491
492/* Nonzero means to allow single precision math even if we're generally
493   being traditional. */
494extern int flag_allow_single_precision;
495
496/* Nonzero means warn about suggesting putting in ()'s.  */
497
498extern int warn_parentheses;
499
500/* Warn if initializer is not completely bracketed.  */
501
502extern int warn_missing_braces;
503
504/* Warn about comparison of signed and unsigned values.  */
505
506extern int warn_sign_compare;
507
508/* Warn about multicharacter constants.  */
509
510extern int warn_multichar;
511
512/* Nonzero means we are reading code that came from a system header file.  */
513
514extern int system_header_p;
515
516/* Nonzero enables objc features.  */
517
518extern int doing_objc_thang;
519
520/* In c-decl.c */
521extern void finish_incomplete_decl PROTO((tree));
522
523#endif /* not _C_TREE_H */
524