df410325fba32b9352c6410624df16972a656ce7
[cparser] / parser.c
1 /*
2  * This file is part of cparser.
3  * Copyright (C) 2007-2008 Matthias Braun <matze@braunis.de>
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License
7  * as published by the Free Software Foundation; either version 2
8  * of the License, or (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
18  * 02111-1307, USA.
19  */
20 #include <config.h>
21
22 #include <assert.h>
23 #include <stdarg.h>
24 #include <stdbool.h>
25
26 #include "parser.h"
27 #include "diagnostic.h"
28 #include "format_check.h"
29 #include "lexer.h"
30 #include "symbol_t.h"
31 #include "token_t.h"
32 #include "types.h"
33 #include "type_t.h"
34 #include "type_hash.h"
35 #include "ast_t.h"
36 #include "lang_features.h"
37 #include "walk_statements.h"
38 #include "warning.h"
39 #include "adt/bitfiddle.h"
40 #include "adt/error.h"
41 #include "adt/array.h"
42
43 /** if wchar_t is equal to unsigned short. */
44 bool opt_short_wchar_t =
45 #ifdef _WIN32
46         true;
47 #else
48         false;
49 #endif
50
51 //#define PRINT_TOKENS
52 #define MAX_LOOKAHEAD 2
53
54 typedef struct {
55         declaration_t *old_declaration;
56         symbol_t      *symbol;
57         unsigned short namespc;
58 } stack_entry_t;
59
60 typedef struct argument_list_t argument_list_t;
61 struct argument_list_t {
62         long              argument;
63         argument_list_t  *next;
64 };
65
66 typedef struct gnu_attribute_t gnu_attribute_t;
67 struct gnu_attribute_t {
68         gnu_attribute_kind_t kind;           /**< The kind of the GNU attribute. */
69         gnu_attribute_t     *next;
70         bool                 invalid;        /**< Set if this attribute had argument errors, */
71         bool                 have_arguments; /**< True, if this attribute has arguments. */
72         union {
73                 size_t              value;
74                 string_t            string;
75                 atomic_type_kind_t  akind;
76                 long                argument;  /**< Single argument. */
77                 argument_list_t    *arguments; /**< List of argument expressions. */
78         } u;
79 };
80
81 typedef struct declaration_specifiers_t  declaration_specifiers_t;
82 struct declaration_specifiers_t {
83         source_position_t  source_position;
84         unsigned char      declared_storage_class;
85         unsigned char      alignment;         /**< Alignment, 0 if not set. */
86         unsigned int       is_inline : 1;
87         unsigned int       deprecated : 1;
88         decl_modifiers_t   modifiers;         /**< declaration modifiers */
89         gnu_attribute_t   *gnu_attributes;    /**< list of GNU attributes */
90         const char        *deprecated_string; /**< can be set if declaration was marked deprecated. */
91         symbol_t          *get_property_sym;  /**< the name of the get property if set. */
92         symbol_t          *put_property_sym;  /**< the name of the put property if set. */
93         type_t            *type;
94 };
95
96 /**
97  * An environment for parsing initializers (and compound literals).
98  */
99 typedef struct parse_initializer_env_t {
100         type_t        *type;        /**< the type of the initializer. In case of an
101                                          array type with unspecified size this gets
102                                          adjusted to the actual size. */
103         declaration_t *declaration; /**< the declaration that is initialized if any */
104         bool           must_be_constant;
105 } parse_initializer_env_t;
106
107 typedef declaration_t* (*parsed_declaration_func) (declaration_t *declaration, bool is_definition);
108
109 /** The current token. */
110 static token_t             token;
111 /** The lookahead ring-buffer. */
112 static token_t             lookahead_buffer[MAX_LOOKAHEAD];
113 /** Position of the next token in the lookahead buffer. */
114 static int                 lookahead_bufpos;
115 static stack_entry_t      *environment_stack = NULL;
116 static stack_entry_t      *label_stack       = NULL;
117 static stack_entry_t      *local_label_stack = NULL;
118 /** The global file scope. */
119 static scope_t            *file_scope        = NULL;
120 /** The current scope. */
121 static scope_t            *scope             = NULL;
122 static declaration_t      *last_declaration  = NULL;
123 /** Point to the current function declaration if inside a function. */
124 static declaration_t      *current_function  = NULL;
125 static declaration_t      *current_init_decl = NULL;
126 static switch_statement_t *current_switch    = NULL;
127 static statement_t        *current_loop      = NULL;
128 static statement_t        *current_parent    = NULL;
129 static ms_try_statement_t *current_try       = NULL;
130 static goto_statement_t   *goto_first        = NULL;
131 static goto_statement_t   *goto_last         = NULL;
132 static label_statement_t  *label_first       = NULL;
133 static label_statement_t  *label_last        = NULL;
134 /** current translation unit. */
135 static translation_unit_t *unit              = NULL;
136 /** true if we are in a type property context (evaluation only for type. */
137 static bool                in_type_prop      = false;
138 /** true in we are in a __extension__ context. */
139 static bool                in_gcc_extension  = false;
140 static struct obstack      temp_obst;
141
142
143 #define PUSH_PARENT(stmt)                          \
144         statement_t *const prev_parent = current_parent; \
145         ((void)(current_parent = (stmt)))
146 #define POP_PARENT ((void)(current_parent = prev_parent))
147
148 static source_position_t null_position = { NULL, 0 };
149
150 /** special symbol used for anonymous entities. */
151 static const symbol_t *sym_anonymous = NULL;
152
153 /* symbols for Microsoft extended-decl-modifier */
154 static const symbol_t *sym_align      = NULL;
155 static const symbol_t *sym_allocate   = NULL;
156 static const symbol_t *sym_dllimport  = NULL;
157 static const symbol_t *sym_dllexport  = NULL;
158 static const symbol_t *sym_naked      = NULL;
159 static const symbol_t *sym_noinline   = NULL;
160 static const symbol_t *sym_noreturn   = NULL;
161 static const symbol_t *sym_nothrow    = NULL;
162 static const symbol_t *sym_novtable   = NULL;
163 static const symbol_t *sym_property   = NULL;
164 static const symbol_t *sym_get        = NULL;
165 static const symbol_t *sym_put        = NULL;
166 static const symbol_t *sym_selectany  = NULL;
167 static const symbol_t *sym_thread     = NULL;
168 static const symbol_t *sym_uuid       = NULL;
169 static const symbol_t *sym_deprecated = NULL;
170 static const symbol_t *sym_restrict   = NULL;
171 static const symbol_t *sym_noalias    = NULL;
172
173 /** The token anchor set */
174 static unsigned char token_anchor_set[T_LAST_TOKEN];
175
176 /** The current source position. */
177 #define HERE (&token.source_position)
178
179 /** true if we are in GCC mode. */
180 #define GNU_MODE ((c_mode & _GNUC) || in_gcc_extension)
181
182 static type_t *type_valist;
183
184 static statement_t *parse_compound_statement(bool inside_expression_statement);
185 static statement_t *parse_statement(void);
186
187 static expression_t *parse_sub_expression(unsigned precedence);
188 static expression_t *parse_expression(void);
189 static type_t       *parse_typename(void);
190
191 static void parse_compound_type_entries(declaration_t *compound_declaration);
192 static declaration_t *parse_declarator(
193                 const declaration_specifiers_t *specifiers, bool may_be_abstract);
194 static declaration_t *record_declaration(declaration_t *declaration, bool is_definition);
195
196 static void semantic_comparison(binary_expression_t *expression);
197
198 #define STORAGE_CLASSES     \
199         case T_typedef:         \
200         case T_extern:          \
201         case T_static:          \
202         case T_auto:            \
203         case T_register:        \
204         case T___thread:
205
206 #define TYPE_QUALIFIERS     \
207         case T_const:           \
208         case T_restrict:        \
209         case T_volatile:        \
210         case T_inline:          \
211         case T__forceinline:    \
212         case T___attribute__:
213
214 #ifdef PROVIDE_COMPLEX
215 #define COMPLEX_SPECIFIERS  \
216         case T__Complex:
217 #define IMAGINARY_SPECIFIERS \
218         case T__Imaginary:
219 #else
220 #define COMPLEX_SPECIFIERS
221 #define IMAGINARY_SPECIFIERS
222 #endif
223
224 #define TYPE_SPECIFIERS       \
225         case T_void:              \
226         case T_char:              \
227         case T_short:             \
228         case T_int:               \
229         case T_long:              \
230         case T_float:             \
231         case T_double:            \
232         case T_signed:            \
233         case T_unsigned:          \
234         case T__Bool:             \
235         case T_struct:            \
236         case T_union:             \
237         case T_enum:              \
238         case T___typeof__:        \
239         case T___builtin_va_list: \
240         case T__declspec:         \
241         COMPLEX_SPECIFIERS        \
242         IMAGINARY_SPECIFIERS
243
244 #define DECLARATION_START   \
245         STORAGE_CLASSES         \
246         TYPE_QUALIFIERS         \
247         TYPE_SPECIFIERS
248
249 #define TYPENAME_START      \
250         TYPE_QUALIFIERS         \
251         TYPE_SPECIFIERS
252
253 /**
254  * Allocate an AST node with given size and
255  * initialize all fields with zero.
256  */
257 static void *allocate_ast_zero(size_t size)
258 {
259         void *res = allocate_ast(size);
260         memset(res, 0, size);
261         return res;
262 }
263
264 static declaration_t *allocate_declaration_zero(void)
265 {
266         declaration_t *declaration = allocate_ast_zero(sizeof(declaration_t));
267         declaration->type      = type_error_type;
268         declaration->alignment = 0;
269         return declaration;
270 }
271
272 /**
273  * Returns the size of a statement node.
274  *
275  * @param kind  the statement kind
276  */
277 static size_t get_statement_struct_size(statement_kind_t kind)
278 {
279         static const size_t sizes[] = {
280                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
281                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
282                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
283                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
284                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
285                 [STATEMENT_IF]          = sizeof(if_statement_t),
286                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
287                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
288                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
289                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
290                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
291                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
292                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
293                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
294                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
295                 [STATEMENT_FOR]         = sizeof(for_statement_t),
296                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
297                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
298                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
299         };
300         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
301         assert(sizes[kind] != 0);
302         return sizes[kind];
303 }
304
305 /**
306  * Returns the size of an expression node.
307  *
308  * @param kind  the expression kind
309  */
310 static size_t get_expression_struct_size(expression_kind_t kind)
311 {
312         static const size_t sizes[] = {
313                 [EXPR_INVALID]                 = sizeof(expression_base_t),
314                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
315                 [EXPR_CONST]                   = sizeof(const_expression_t),
316                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
317                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
318                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
319                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
320                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
321                 [EXPR_CALL]                    = sizeof(call_expression_t),
322                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
323                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
324                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
325                 [EXPR_SELECT]                  = sizeof(select_expression_t),
326                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
327                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
328                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
329                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
330                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
331                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
332                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
333                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
334                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
335                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
336                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
337                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
338                 [EXPR_LABEL_ADDRESS]           = sizeof(label_address_expression_t),
339         };
340         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
341                 return sizes[EXPR_UNARY_FIRST];
342         }
343         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
344                 return sizes[EXPR_BINARY_FIRST];
345         }
346         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
347         assert(sizes[kind] != 0);
348         return sizes[kind];
349 }
350
351 /**
352  * Allocate a statement node of given kind and initialize all
353  * fields with zero.
354  */
355 static statement_t *allocate_statement_zero(statement_kind_t kind)
356 {
357         size_t       size = get_statement_struct_size(kind);
358         statement_t *res  = allocate_ast_zero(size);
359
360         res->base.kind            = kind;
361         res->base.parent          = current_parent;
362         res->base.source_position = token.source_position;
363         return res;
364 }
365
366 /**
367  * Allocate an expression node of given kind and initialize all
368  * fields with zero.
369  */
370 static expression_t *allocate_expression_zero(expression_kind_t kind)
371 {
372         size_t        size = get_expression_struct_size(kind);
373         expression_t *res  = allocate_ast_zero(size);
374
375         res->base.kind = kind;
376         res->base.type = type_error_type;
377         return res;
378 }
379
380 /**
381  * Creates a new invalid expression.
382  */
383 static expression_t *create_invalid_expression(void)
384 {
385         expression_t *expression         = allocate_expression_zero(EXPR_INVALID);
386         expression->base.source_position = token.source_position;
387         return expression;
388 }
389
390 /**
391  * Creates a new invalid statement.
392  */
393 static statement_t *create_invalid_statement(void)
394 {
395         return allocate_statement_zero(STATEMENT_INVALID);
396 }
397
398 /**
399  * Allocate a new empty statement.
400  */
401 static statement_t *create_empty_statement(void)
402 {
403         return allocate_statement_zero(STATEMENT_EMPTY);
404 }
405
406 /**
407  * Returns the size of a type node.
408  *
409  * @param kind  the type kind
410  */
411 static size_t get_type_struct_size(type_kind_t kind)
412 {
413         static const size_t sizes[] = {
414                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
415                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
416                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
417                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
418                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
419                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
420                 [TYPE_ENUM]            = sizeof(enum_type_t),
421                 [TYPE_FUNCTION]        = sizeof(function_type_t),
422                 [TYPE_POINTER]         = sizeof(pointer_type_t),
423                 [TYPE_ARRAY]           = sizeof(array_type_t),
424                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
425                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
426                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
427         };
428         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
429         assert(kind <= TYPE_TYPEOF);
430         assert(sizes[kind] != 0);
431         return sizes[kind];
432 }
433
434 /**
435  * Allocate a type node of given kind and initialize all
436  * fields with zero.
437  *
438  * @param kind             type kind to allocate
439  * @param source_position  the source position of the type definition
440  */
441 static type_t *allocate_type_zero(type_kind_t kind, const source_position_t *source_position)
442 {
443         size_t  size = get_type_struct_size(kind);
444         type_t *res  = obstack_alloc(type_obst, size);
445         memset(res, 0, size);
446
447         res->base.kind            = kind;
448         res->base.source_position = *source_position;
449         return res;
450 }
451
452 /**
453  * Returns the size of an initializer node.
454  *
455  * @param kind  the initializer kind
456  */
457 static size_t get_initializer_size(initializer_kind_t kind)
458 {
459         static const size_t sizes[] = {
460                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
461                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
462                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
463                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
464                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
465         };
466         assert(kind < sizeof(sizes) / sizeof(*sizes));
467         assert(sizes[kind] != 0);
468         return sizes[kind];
469 }
470
471 /**
472  * Allocate an initializer node of given kind and initialize all
473  * fields with zero.
474  */
475 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
476 {
477         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
478         result->kind          = kind;
479
480         return result;
481 }
482
483 /**
484  * Free a type from the type obstack.
485  */
486 static void free_type(void *type)
487 {
488         obstack_free(type_obst, type);
489 }
490
491 /**
492  * Returns the index of the top element of the environment stack.
493  */
494 static size_t environment_top(void)
495 {
496         return ARR_LEN(environment_stack);
497 }
498
499 /**
500  * Returns the index of the top element of the global label stack.
501  */
502 static size_t label_top(void)
503 {
504         return ARR_LEN(label_stack);
505 }
506
507 /**
508  * Returns the index of the top element of the local label stack.
509  */
510 static size_t local_label_top(void)
511 {
512         return ARR_LEN(local_label_stack);
513 }
514
515 /**
516  * Return the next token.
517  */
518 static inline void next_token(void)
519 {
520         token                              = lookahead_buffer[lookahead_bufpos];
521         lookahead_buffer[lookahead_bufpos] = lexer_token;
522         lexer_next_token();
523
524         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
525
526 #ifdef PRINT_TOKENS
527         print_token(stderr, &token);
528         fprintf(stderr, "\n");
529 #endif
530 }
531
532 /**
533  * Return the next token with a given lookahead.
534  */
535 static inline const token_t *look_ahead(int num)
536 {
537         assert(num > 0 && num <= MAX_LOOKAHEAD);
538         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
539         return &lookahead_buffer[pos];
540 }
541
542 /**
543  * Adds a token to the token anchor set (a multi-set).
544  */
545 static void add_anchor_token(int token_type)
546 {
547         assert(0 <= token_type && token_type < T_LAST_TOKEN);
548         ++token_anchor_set[token_type];
549 }
550
551 static int save_and_reset_anchor_state(int token_type)
552 {
553         assert(0 <= token_type && token_type < T_LAST_TOKEN);
554         int count = token_anchor_set[token_type];
555         token_anchor_set[token_type] = 0;
556         return count;
557 }
558
559 static void restore_anchor_state(int token_type, int count)
560 {
561         assert(0 <= token_type && token_type < T_LAST_TOKEN);
562         token_anchor_set[token_type] = count;
563 }
564
565 /**
566  * Remove a token from the token anchor set (a multi-set).
567  */
568 static void rem_anchor_token(int token_type)
569 {
570         assert(0 <= token_type && token_type < T_LAST_TOKEN);
571         assert(token_anchor_set[token_type] != 0);
572         --token_anchor_set[token_type];
573 }
574
575 static bool at_anchor(void)
576 {
577         if (token.type < 0)
578                 return false;
579         return token_anchor_set[token.type];
580 }
581
582 /**
583  * Eat tokens until a matching token is found.
584  */
585 static void eat_until_matching_token(int type)
586 {
587         int end_token;
588         switch (type) {
589                 case '(': end_token = ')';  break;
590                 case '{': end_token = '}';  break;
591                 case '[': end_token = ']';  break;
592                 default:  end_token = type; break;
593         }
594
595         unsigned parenthesis_count = 0;
596         unsigned brace_count       = 0;
597         unsigned bracket_count     = 0;
598         while (token.type        != end_token ||
599                parenthesis_count != 0         ||
600                brace_count       != 0         ||
601                bracket_count     != 0) {
602                 switch (token.type) {
603                 case T_EOF: return;
604                 case '(': ++parenthesis_count; break;
605                 case '{': ++brace_count;       break;
606                 case '[': ++bracket_count;     break;
607
608                 case ')':
609                         if (parenthesis_count > 0)
610                                 --parenthesis_count;
611                         goto check_stop;
612
613                 case '}':
614                         if (brace_count > 0)
615                                 --brace_count;
616                         goto check_stop;
617
618                 case ']':
619                         if (bracket_count > 0)
620                                 --bracket_count;
621 check_stop:
622                         if (token.type        == end_token &&
623                             parenthesis_count == 0         &&
624                             brace_count       == 0         &&
625                             bracket_count     == 0)
626                                 return;
627                         break;
628
629                 default:
630                         break;
631                 }
632                 next_token();
633         }
634 }
635
636 /**
637  * Eat input tokens until an anchor is found.
638  */
639 static void eat_until_anchor(void)
640 {
641         while (token_anchor_set[token.type] == 0) {
642                 if (token.type == '(' || token.type == '{' || token.type == '[')
643                         eat_until_matching_token(token.type);
644                 next_token();
645         }
646 }
647
648 static void eat_block(void)
649 {
650         eat_until_matching_token('{');
651         if (token.type == '}')
652                 next_token();
653 }
654
655 #define eat(token_type)  do { assert(token.type == token_type); next_token(); } while (0)
656
657 /**
658  * Report a parse error because an expected token was not found.
659  */
660 static
661 #if defined __GNUC__ && __GNUC__ >= 4
662 __attribute__((sentinel))
663 #endif
664 void parse_error_expected(const char *message, ...)
665 {
666         if (message != NULL) {
667                 errorf(HERE, "%s", message);
668         }
669         va_list ap;
670         va_start(ap, message);
671         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
672         va_end(ap);
673 }
674
675 /**
676  * Report a type error.
677  */
678 static void type_error(const char *msg, const source_position_t *source_position,
679                        type_t *type)
680 {
681         errorf(source_position, "%s, but found type '%T'", msg, type);
682 }
683
684 /**
685  * Report an incompatible type.
686  */
687 static void type_error_incompatible(const char *msg,
688                 const source_position_t *source_position, type_t *type1, type_t *type2)
689 {
690         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
691                msg, type1, type2);
692 }
693
694 /**
695  * Expect the the current token is the expected token.
696  * If not, generate an error, eat the current statement,
697  * and goto the end_error label.
698  */
699 #define expect(expected)                                  \
700         do {                                                  \
701                 if (UNLIKELY(token.type != (expected))) {         \
702                         parse_error_expected(NULL, (expected), NULL); \
703                         add_anchor_token(expected);                   \
704                         eat_until_anchor();                           \
705                         if (token.type == expected)                   \
706                                 next_token();                             \
707                         rem_anchor_token(expected);                   \
708                         goto end_error;                               \
709                 }                                                 \
710                 next_token();                                     \
711         } while (0)
712
713 static void scope_push(scope_t *new_scope)
714 {
715         if (scope != NULL) {
716                 scope->last_declaration = last_declaration;
717                 new_scope->depth        = scope->depth + 1;
718         }
719         new_scope->parent = scope;
720         scope             = new_scope;
721
722         last_declaration = new_scope->last_declaration;
723 }
724
725 static void scope_pop(void)
726 {
727         scope->last_declaration = last_declaration;
728         scope = scope->parent;
729         last_declaration = scope->last_declaration;
730 }
731
732 /**
733  * Search a symbol in a given namespace and returns its declaration or
734  * NULL if this symbol was not found.
735  */
736 static declaration_t *get_declaration(const symbol_t *const symbol,
737                                       const namespace_t namespc)
738 {
739         declaration_t *declaration = symbol->declaration;
740         for( ; declaration != NULL; declaration = declaration->symbol_next) {
741                 if (declaration->namespc == namespc)
742                         return declaration;
743         }
744
745         return NULL;
746 }
747
748 /**
749  * pushs an environment_entry on the environment stack and links the
750  * corresponding symbol to the new entry
751  */
752 static void stack_push(stack_entry_t **stack_ptr, declaration_t *declaration)
753 {
754         symbol_t    *symbol  = declaration->symbol;
755         namespace_t  namespc = (namespace_t) declaration->namespc;
756
757         /* replace/add declaration into declaration list of the symbol */
758         declaration_t **anchor;
759         declaration_t  *iter;
760         for (anchor = &symbol->declaration;; anchor = &iter->symbol_next) {
761                 iter = *anchor;
762                 if (iter == NULL)
763                         break;
764
765                 /* replace an entry? */
766                 if (iter->namespc == namespc) {
767                         declaration->symbol_next = iter->symbol_next;
768                         break;
769                 }
770         }
771         *anchor = declaration;
772
773         /* remember old declaration */
774         stack_entry_t entry;
775         entry.symbol          = symbol;
776         entry.old_declaration = iter;
777         entry.namespc         = (unsigned short) namespc;
778         ARR_APP1(stack_entry_t, *stack_ptr, entry);
779 }
780
781 /**
782  * Push a declaration on the environment stack.
783  *
784  * @param declaration  the declaration
785  */
786 static void environment_push(declaration_t *declaration)
787 {
788         assert(declaration->source_position.input_name != NULL);
789         assert(declaration->parent_scope != NULL);
790         stack_push(&environment_stack, declaration);
791 }
792
793 /**
794  * Push a declaration on the global label stack.
795  *
796  * @param declaration  the declaration
797  */
798 static void label_push(declaration_t *declaration)
799 {
800         declaration->parent_scope = &current_function->scope;
801         stack_push(&label_stack, declaration);
802 }
803
804 /**
805  * Push a declaration of the local label stack.
806  *
807  * @param declaration  the declaration
808  */
809 static void local_label_push(declaration_t *declaration)
810 {
811         assert(declaration->parent_scope != NULL);
812         stack_push(&local_label_stack, declaration);
813 }
814
815 /**
816  * pops symbols from the environment stack until @p new_top is the top element
817  */
818 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
819 {
820         stack_entry_t *stack = *stack_ptr;
821         size_t         top   = ARR_LEN(stack);
822         size_t         i;
823
824         assert(new_top <= top);
825         if (new_top == top)
826                 return;
827
828         for(i = top; i > new_top; --i) {
829                 stack_entry_t *entry = &stack[i - 1];
830
831                 declaration_t *old_declaration = entry->old_declaration;
832                 symbol_t      *symbol          = entry->symbol;
833                 namespace_t    namespc         = (namespace_t)entry->namespc;
834
835                 /* replace/remove declaration */
836                 declaration_t **anchor;
837                 declaration_t  *iter;
838                 for (anchor = &symbol->declaration;; anchor = &iter->symbol_next) {
839                         iter = *anchor;
840                         assert(iter != NULL);
841                         /* replace an entry? */
842                         if (iter->namespc == namespc)
843                                 break;
844                 }
845
846                 /* Not all declarations adhere scopes (e.g. jump labels), so this
847                  * correction is necessary */
848                 if (old_declaration != NULL) {
849                         old_declaration->symbol_next = iter->symbol_next;
850                         *anchor = old_declaration;
851                 } else {
852                         *anchor = iter->symbol_next;
853                 }
854         }
855
856         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
857 }
858
859 /**
860  * Pop all entries from the environment stack until the new_top
861  * is reached.
862  *
863  * @param new_top  the new stack top
864  */
865 static void environment_pop_to(size_t new_top)
866 {
867         stack_pop_to(&environment_stack, new_top);
868 }
869
870 /**
871  * Pop all entries from the global label stack until the new_top
872  * is reached.
873  *
874  * @param new_top  the new stack top
875  */
876 static void label_pop_to(size_t new_top)
877 {
878         stack_pop_to(&label_stack, new_top);
879 }
880
881 /**
882  * Pop all entries from the local label stack until the new_top
883  * is reached.
884  *
885  * @param new_top  the new stack top
886  */
887 static void local_label_pop_to(size_t new_top)
888 {
889         stack_pop_to(&local_label_stack, new_top);
890 }
891
892
893 static int get_akind_rank(atomic_type_kind_t akind)
894 {
895         return (int) akind;
896 }
897
898 static int get_rank(const type_t *type)
899 {
900         assert(!is_typeref(type));
901         /* The C-standard allows promoting enums to int or unsigned int (see Â§ 7.2.2
902          * and esp. footnote 108). However we can't fold constants (yet), so we
903          * can't decide whether unsigned int is possible, while int always works.
904          * (unsigned int would be preferable when possible... for stuff like
905          *  struct { enum { ... } bla : 4; } ) */
906         if (type->kind == TYPE_ENUM)
907                 return get_akind_rank(ATOMIC_TYPE_INT);
908
909         assert(type->kind == TYPE_ATOMIC);
910         return get_akind_rank(type->atomic.akind);
911 }
912
913 static type_t *promote_integer(type_t *type)
914 {
915         if (type->kind == TYPE_BITFIELD)
916                 type = type->bitfield.base_type;
917
918         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
919                 type = type_int;
920
921         return type;
922 }
923
924 /**
925  * Create a cast expression.
926  *
927  * @param expression  the expression to cast
928  * @param dest_type   the destination type
929  */
930 static expression_t *create_cast_expression(expression_t *expression,
931                                             type_t *dest_type)
932 {
933         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
934
935         cast->unary.value = expression;
936         cast->base.type   = dest_type;
937
938         return cast;
939 }
940
941 /**
942  * Check if a given expression represents the 0 pointer constant.
943  */
944 static bool is_null_pointer_constant(const expression_t *expression)
945 {
946         /* skip void* cast */
947         if (expression->kind == EXPR_UNARY_CAST
948                         || expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
949                 expression = expression->unary.value;
950         }
951
952         /* TODO: not correct yet, should be any constant integer expression
953          * which evaluates to 0 */
954         if (expression->kind != EXPR_CONST)
955                 return false;
956
957         type_t *const type = skip_typeref(expression->base.type);
958         if (!is_type_integer(type))
959                 return false;
960
961         return expression->conste.v.int_value == 0;
962 }
963
964 /**
965  * Create an implicit cast expression.
966  *
967  * @param expression  the expression to cast
968  * @param dest_type   the destination type
969  */
970 static expression_t *create_implicit_cast(expression_t *expression,
971                                           type_t *dest_type)
972 {
973         type_t *const source_type = expression->base.type;
974
975         if (source_type == dest_type)
976                 return expression;
977
978         return create_cast_expression(expression, dest_type);
979 }
980
981 typedef enum assign_error_t {
982         ASSIGN_SUCCESS,
983         ASSIGN_ERROR_INCOMPATIBLE,
984         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
985         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
986         ASSIGN_WARNING_POINTER_FROM_INT,
987         ASSIGN_WARNING_INT_FROM_POINTER
988 } assign_error_t;
989
990 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
991                                 const expression_t *const right,
992                                 const char *context,
993                                 const source_position_t *source_position)
994 {
995         type_t *const orig_type_right = right->base.type;
996         type_t *const type_left       = skip_typeref(orig_type_left);
997         type_t *const type_right      = skip_typeref(orig_type_right);
998
999         switch (error) {
1000         case ASSIGN_SUCCESS:
1001                 return;
1002         case ASSIGN_ERROR_INCOMPATIBLE:
1003                 errorf(source_position,
1004                        "destination type '%T' in %s is incompatible with type '%T'",
1005                        orig_type_left, context, orig_type_right);
1006                 return;
1007
1008         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
1009                 type_t *points_to_left
1010                         = skip_typeref(type_left->pointer.points_to);
1011                 type_t *points_to_right
1012                         = skip_typeref(type_right->pointer.points_to);
1013
1014                 /* the left type has all qualifiers from the right type */
1015                 unsigned missing_qualifiers
1016                         = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1017                 warningf(source_position,
1018                          "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
1019                          orig_type_left, context, orig_type_right, missing_qualifiers);
1020                 return;
1021         }
1022
1023         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
1024                 warningf(source_position,
1025                          "destination type '%T' in %s is incompatible with '%E' of type '%T'",
1026                                  orig_type_left, context, right, orig_type_right);
1027                 return;
1028
1029         case ASSIGN_WARNING_POINTER_FROM_INT:
1030                 warningf(source_position,
1031                          "%s makes pointer '%T' from integer '%T' without a cast",
1032                                  context, orig_type_left, orig_type_right);
1033                 return;
1034
1035         case ASSIGN_WARNING_INT_FROM_POINTER:
1036                 warningf(source_position,
1037                                 "%s makes integer '%T' from pointer '%T' without a cast",
1038                                 context, orig_type_left, orig_type_right);
1039                 return;
1040
1041         default:
1042                 panic("invalid error value");
1043         }
1044 }
1045
1046 /** Implements the rules from Â§ 6.5.16.1 */
1047 static assign_error_t semantic_assign(type_t *orig_type_left,
1048                                       const expression_t *const right)
1049 {
1050         type_t *const orig_type_right = right->base.type;
1051         type_t *const type_left       = skip_typeref(orig_type_left);
1052         type_t *const type_right      = skip_typeref(orig_type_right);
1053
1054         if (is_type_pointer(type_left)) {
1055                 if (is_null_pointer_constant(right)) {
1056                         return ASSIGN_SUCCESS;
1057                 } else if (is_type_pointer(type_right)) {
1058                         type_t *points_to_left
1059                                 = skip_typeref(type_left->pointer.points_to);
1060                         type_t *points_to_right
1061                                 = skip_typeref(type_right->pointer.points_to);
1062                         assign_error_t res = ASSIGN_SUCCESS;
1063
1064                         /* the left type has all qualifiers from the right type */
1065                         unsigned missing_qualifiers
1066                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1067                         if (missing_qualifiers != 0) {
1068                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1069                         }
1070
1071                         points_to_left  = get_unqualified_type(points_to_left);
1072                         points_to_right = get_unqualified_type(points_to_right);
1073
1074                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID) ||
1075                                         is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1076                                 return res;
1077                         }
1078
1079                         if (!types_compatible(points_to_left, points_to_right)) {
1080                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1081                         }
1082
1083                         return res;
1084                 } else if (is_type_integer(type_right)) {
1085                         return ASSIGN_WARNING_POINTER_FROM_INT;
1086                 }
1087         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1088             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1089                 && is_type_pointer(type_right))) {
1090                 return ASSIGN_SUCCESS;
1091         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1092                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1093                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1094                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1095                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1096                         return ASSIGN_SUCCESS;
1097                 }
1098         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1099                 return ASSIGN_WARNING_INT_FROM_POINTER;
1100         }
1101
1102         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1103                 return ASSIGN_SUCCESS;
1104
1105         return ASSIGN_ERROR_INCOMPATIBLE;
1106 }
1107
1108 static expression_t *parse_constant_expression(void)
1109 {
1110         /* start parsing at precedence 7 (conditional expression) */
1111         expression_t *result = parse_sub_expression(7);
1112
1113         if (!is_constant_expression(result)) {
1114                 errorf(&result->base.source_position,
1115                        "expression '%E' is not constant\n", result);
1116         }
1117
1118         return result;
1119 }
1120
1121 static expression_t *parse_assignment_expression(void)
1122 {
1123         /* start parsing at precedence 2 (assignment expression) */
1124         return parse_sub_expression(2);
1125 }
1126
1127 static type_t *make_global_typedef(const char *name, type_t *type)
1128 {
1129         symbol_t *const symbol       = symbol_table_insert(name);
1130
1131         declaration_t *const declaration = allocate_declaration_zero();
1132         declaration->namespc                = NAMESPACE_NORMAL;
1133         declaration->storage_class          = STORAGE_CLASS_TYPEDEF;
1134         declaration->declared_storage_class = STORAGE_CLASS_TYPEDEF;
1135         declaration->type                   = type;
1136         declaration->symbol                 = symbol;
1137         declaration->source_position        = builtin_source_position;
1138         declaration->implicit               = true;
1139
1140         record_declaration(declaration, false);
1141
1142         type_t *typedef_type               = allocate_type_zero(TYPE_TYPEDEF, &builtin_source_position);
1143         typedef_type->typedeft.declaration = declaration;
1144
1145         return typedef_type;
1146 }
1147
1148 static string_t parse_string_literals(void)
1149 {
1150         assert(token.type == T_STRING_LITERAL);
1151         string_t result = token.v.string;
1152
1153         next_token();
1154
1155         while (token.type == T_STRING_LITERAL) {
1156                 result = concat_strings(&result, &token.v.string);
1157                 next_token();
1158         }
1159
1160         return result;
1161 }
1162
1163 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1164         [GNU_AK_CONST]                  = "const",
1165         [GNU_AK_VOLATILE]               = "volatile",
1166         [GNU_AK_CDECL]                  = "cdecl",
1167         [GNU_AK_STDCALL]                = "stdcall",
1168         [GNU_AK_FASTCALL]               = "fastcall",
1169         [GNU_AK_DEPRECATED]             = "deprecated",
1170         [GNU_AK_NOINLINE]               = "noinline",
1171         [GNU_AK_NORETURN]               = "noreturn",
1172         [GNU_AK_NAKED]                  = "naked",
1173         [GNU_AK_PURE]                   = "pure",
1174         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1175         [GNU_AK_MALLOC]                 = "malloc",
1176         [GNU_AK_WEAK]                   = "weak",
1177         [GNU_AK_CONSTRUCTOR]            = "constructor",
1178         [GNU_AK_DESTRUCTOR]             = "destructor",
1179         [GNU_AK_NOTHROW]                = "nothrow",
1180         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1181         [GNU_AK_COMMON]                 = "common",
1182         [GNU_AK_NOCOMMON]               = "nocommon",
1183         [GNU_AK_PACKED]                 = "packed",
1184         [GNU_AK_SHARED]                 = "shared",
1185         [GNU_AK_NOTSHARED]              = "notshared",
1186         [GNU_AK_USED]                   = "used",
1187         [GNU_AK_UNUSED]                 = "unused",
1188         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1189         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1190         [GNU_AK_LONGCALL]               = "longcall",
1191         [GNU_AK_SHORTCALL]              = "shortcall",
1192         [GNU_AK_LONG_CALL]              = "long_call",
1193         [GNU_AK_SHORT_CALL]             = "short_call",
1194         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1195         [GNU_AK_INTERRUPT]              = "interrupt",
1196         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1197         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1198         [GNU_AK_NESTING]                = "nesting",
1199         [GNU_AK_NEAR]                   = "near",
1200         [GNU_AK_FAR]                    = "far",
1201         [GNU_AK_SIGNAL]                 = "signal",
1202         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1203         [GNU_AK_TINY_DATA]              = "tiny_data",
1204         [GNU_AK_SAVEALL]                = "saveall",
1205         [GNU_AK_FLATTEN]                = "flatten",
1206         [GNU_AK_SSEREGPARM]             = "sseregparm",
1207         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1208         [GNU_AK_RETURN_TWICE]           = "return_twice",
1209         [GNU_AK_MAY_ALIAS]              = "may_alias",
1210         [GNU_AK_MS_STRUCT]              = "ms_struct",
1211         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1212         [GNU_AK_DLLIMPORT]              = "dllimport",
1213         [GNU_AK_DLLEXPORT]              = "dllexport",
1214         [GNU_AK_ALIGNED]                = "aligned",
1215         [GNU_AK_ALIAS]                  = "alias",
1216         [GNU_AK_SECTION]                = "section",
1217         [GNU_AK_FORMAT]                 = "format",
1218         [GNU_AK_FORMAT_ARG]             = "format_arg",
1219         [GNU_AK_WEAKREF]                = "weakref",
1220         [GNU_AK_NONNULL]                = "nonnull",
1221         [GNU_AK_TLS_MODEL]              = "tls_model",
1222         [GNU_AK_VISIBILITY]             = "visibility",
1223         [GNU_AK_REGPARM]                = "regparm",
1224         [GNU_AK_MODE]                   = "mode",
1225         [GNU_AK_MODEL]                  = "model",
1226         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1227         [GNU_AK_SP_SWITCH]              = "sp_switch",
1228         [GNU_AK_SENTINEL]               = "sentinel"
1229 };
1230
1231 /**
1232  * compare two string, ignoring double underscores on the second.
1233  */
1234 static int strcmp_underscore(const char *s1, const char *s2)
1235 {
1236         if (s2[0] == '_' && s2[1] == '_') {
1237                 size_t len2 = strlen(s2);
1238                 size_t len1 = strlen(s1);
1239                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1240                         return strncmp(s1, s2+2, len2-4);
1241                 }
1242         }
1243
1244         return strcmp(s1, s2);
1245 }
1246
1247 /**
1248  * Allocate a new gnu temporal attribute.
1249  */
1250 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1251 {
1252         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1253         attribute->kind            = kind;
1254         attribute->next            = NULL;
1255         attribute->invalid         = false;
1256         attribute->have_arguments  = false;
1257
1258         return attribute;
1259 }
1260
1261 /**
1262  * parse one constant expression argument.
1263  */
1264 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1265 {
1266         expression_t *expression;
1267         add_anchor_token(')');
1268         expression = parse_constant_expression();
1269         rem_anchor_token(')');
1270         expect(')');
1271         attribute->u.argument = fold_constant(expression);
1272         return;
1273 end_error:
1274         attribute->invalid = true;
1275 }
1276
1277 /**
1278  * parse a list of constant expressions arguments.
1279  */
1280 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1281 {
1282         argument_list_t **list = &attribute->u.arguments;
1283         argument_list_t  *entry;
1284         expression_t     *expression;
1285         add_anchor_token(')');
1286         add_anchor_token(',');
1287         while (true) {
1288                 expression = parse_constant_expression();
1289                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1290                 entry->argument = fold_constant(expression);
1291                 entry->next     = NULL;
1292                 *list = entry;
1293                 list = &entry->next;
1294                 if (token.type != ',')
1295                         break;
1296                 next_token();
1297         }
1298         rem_anchor_token(',');
1299         rem_anchor_token(')');
1300         expect(')');
1301         return;
1302 end_error:
1303         attribute->invalid = true;
1304 }
1305
1306 /**
1307  * parse one string literal argument.
1308  */
1309 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1310                                            string_t *string)
1311 {
1312         add_anchor_token('(');
1313         if (token.type != T_STRING_LITERAL) {
1314                 parse_error_expected("while parsing attribute directive",
1315                                      T_STRING_LITERAL, NULL);
1316                 goto end_error;
1317         }
1318         *string = parse_string_literals();
1319         rem_anchor_token('(');
1320         expect(')');
1321         return;
1322 end_error:
1323         attribute->invalid = true;
1324 }
1325
1326 /**
1327  * parse one tls model.
1328  */
1329 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1330 {
1331         static const char *const tls_models[] = {
1332                 "global-dynamic",
1333                 "local-dynamic",
1334                 "initial-exec",
1335                 "local-exec"
1336         };
1337         string_t string = { NULL, 0 };
1338         parse_gnu_attribute_string_arg(attribute, &string);
1339         if (string.begin != NULL) {
1340                 for(size_t i = 0; i < 4; ++i) {
1341                         if (strcmp(tls_models[i], string.begin) == 0) {
1342                                 attribute->u.value = i;
1343                                 return;
1344                         }
1345                 }
1346                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1347         }
1348         attribute->invalid = true;
1349 }
1350
1351 /**
1352  * parse one tls model.
1353  */
1354 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1355 {
1356         static const char *const visibilities[] = {
1357                 "default",
1358                 "protected",
1359                 "hidden",
1360                 "internal"
1361         };
1362         string_t string = { NULL, 0 };
1363         parse_gnu_attribute_string_arg(attribute, &string);
1364         if (string.begin != NULL) {
1365                 for(size_t i = 0; i < 4; ++i) {
1366                         if (strcmp(visibilities[i], string.begin) == 0) {
1367                                 attribute->u.value = i;
1368                                 return;
1369                         }
1370                 }
1371                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1372         }
1373         attribute->invalid = true;
1374 }
1375
1376 /**
1377  * parse one (code) model.
1378  */
1379 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1380 {
1381         static const char *const visibilities[] = {
1382                 "small",
1383                 "medium",
1384                 "large"
1385         };
1386         string_t string = { NULL, 0 };
1387         parse_gnu_attribute_string_arg(attribute, &string);
1388         if (string.begin != NULL) {
1389                 for(int i = 0; i < 3; ++i) {
1390                         if (strcmp(visibilities[i], string.begin) == 0) {
1391                                 attribute->u.value = i;
1392                                 return;
1393                         }
1394                 }
1395                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1396         }
1397         attribute->invalid = true;
1398 }
1399
1400 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1401 {
1402         /* TODO: find out what is allowed here... */
1403
1404         /* at least: byte, word, pointer, list of machine modes
1405          * __XXX___ is interpreted as XXX */
1406         add_anchor_token(')');
1407
1408         if (token.type != T_IDENTIFIER) {
1409                 expect(T_IDENTIFIER);
1410         }
1411
1412         /* This isn't really correct, the backend should provide a list of machine
1413          * specific modes (according to gcc philosophy that is...) */
1414         const char *symbol_str = token.v.symbol->string;
1415         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1416             strcmp_underscore("byte", symbol_str) == 0) {
1417                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1418         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1419                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1420         } else if (strcmp_underscore("SI",      symbol_str) == 0
1421                 || strcmp_underscore("word",    symbol_str) == 0
1422                 || strcmp_underscore("pointer", symbol_str) == 0) {
1423                 attribute->u.akind = ATOMIC_TYPE_INT;
1424         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1425                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1426         } else {
1427                 warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1428                 attribute->invalid = true;
1429         }
1430         next_token();
1431
1432         rem_anchor_token(')');
1433         expect(')');
1434         return;
1435 end_error:
1436         attribute->invalid = true;
1437 }
1438
1439 /**
1440  * parse one interrupt argument.
1441  */
1442 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1443 {
1444         static const char *const interrupts[] = {
1445                 "IRQ",
1446                 "FIQ",
1447                 "SWI",
1448                 "ABORT",
1449                 "UNDEF"
1450         };
1451         string_t string = { NULL, 0 };
1452         parse_gnu_attribute_string_arg(attribute, &string);
1453         if (string.begin != NULL) {
1454                 for(size_t i = 0; i < 5; ++i) {
1455                         if (strcmp(interrupts[i], string.begin) == 0) {
1456                                 attribute->u.value = i;
1457                                 return;
1458                         }
1459                 }
1460                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1461         }
1462         attribute->invalid = true;
1463 }
1464
1465 /**
1466  * parse ( identifier, const expression, const expression )
1467  */
1468 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1469 {
1470         static const char *const format_names[] = {
1471                 "printf",
1472                 "scanf",
1473                 "strftime",
1474                 "strfmon"
1475         };
1476         int i;
1477
1478         if (token.type != T_IDENTIFIER) {
1479                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1480                 goto end_error;
1481         }
1482         const char *name = token.v.symbol->string;
1483         for(i = 0; i < 4; ++i) {
1484                 if (strcmp_underscore(format_names[i], name) == 0)
1485                         break;
1486         }
1487         if (i >= 4) {
1488                 if (warning.attribute)
1489                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1490         }
1491         next_token();
1492
1493         expect(',');
1494         add_anchor_token(')');
1495         add_anchor_token(',');
1496         parse_constant_expression();
1497         rem_anchor_token(',');
1498         rem_anchor_token(')');
1499
1500         expect(',');
1501         add_anchor_token(')');
1502         parse_constant_expression();
1503         rem_anchor_token(')');
1504         expect(')');
1505         return;
1506 end_error:
1507         attribute->u.value = true;
1508 }
1509
1510 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1511 {
1512         if (!attribute->have_arguments)
1513                 return;
1514
1515         /* should have no arguments */
1516         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1517         eat_until_matching_token('(');
1518         /* we have already consumed '(', so we stop before ')', eat it */
1519         eat(')');
1520         attribute->invalid = true;
1521 }
1522
1523 /**
1524  * Parse one GNU attribute.
1525  *
1526  * Note that attribute names can be specified WITH or WITHOUT
1527  * double underscores, ie const or __const__.
1528  *
1529  * The following attributes are parsed without arguments
1530  *  const
1531  *  volatile
1532  *  cdecl
1533  *  stdcall
1534  *  fastcall
1535  *  deprecated
1536  *  noinline
1537  *  noreturn
1538  *  naked
1539  *  pure
1540  *  always_inline
1541  *  malloc
1542  *  weak
1543  *  constructor
1544  *  destructor
1545  *  nothrow
1546  *  transparent_union
1547  *  common
1548  *  nocommon
1549  *  packed
1550  *  shared
1551  *  notshared
1552  *  used
1553  *  unused
1554  *  no_instrument_function
1555  *  warn_unused_result
1556  *  longcall
1557  *  shortcall
1558  *  long_call
1559  *  short_call
1560  *  function_vector
1561  *  interrupt_handler
1562  *  nmi_handler
1563  *  nesting
1564  *  near
1565  *  far
1566  *  signal
1567  *  eightbit_data
1568  *  tiny_data
1569  *  saveall
1570  *  flatten
1571  *  sseregparm
1572  *  externally_visible
1573  *  return_twice
1574  *  may_alias
1575  *  ms_struct
1576  *  gcc_struct
1577  *  dllimport
1578  *  dllexport
1579  *
1580  * The following attributes are parsed with arguments
1581  *  aligned( const expression )
1582  *  alias( string literal )
1583  *  section( string literal )
1584  *  format( identifier, const expression, const expression )
1585  *  format_arg( const expression )
1586  *  tls_model( string literal )
1587  *  visibility( string literal )
1588  *  regparm( const expression )
1589  *  model( string leteral )
1590  *  trap_exit( const expression )
1591  *  sp_switch( string literal )
1592  *
1593  * The following attributes might have arguments
1594  *  weak_ref( string literal )
1595  *  non_null( const expression // ',' )
1596  *  interrupt( string literal )
1597  *  sentinel( constant expression )
1598  */
1599 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1600 {
1601         gnu_attribute_t *head      = *attributes;
1602         gnu_attribute_t *last      = *attributes;
1603         decl_modifiers_t modifiers = 0;
1604         gnu_attribute_t *attribute;
1605
1606         eat(T___attribute__);
1607         expect('(');
1608         expect('(');
1609
1610         if (token.type != ')') {
1611                 /* find the end of the list */
1612                 if (last != NULL) {
1613                         while (last->next != NULL)
1614                                 last = last->next;
1615                 }
1616
1617                 /* non-empty attribute list */
1618                 while (true) {
1619                         const char *name;
1620                         if (token.type == T_const) {
1621                                 name = "const";
1622                         } else if (token.type == T_volatile) {
1623                                 name = "volatile";
1624                         } else if (token.type == T_cdecl) {
1625                                 /* __attribute__((cdecl)), WITH ms mode */
1626                                 name = "cdecl";
1627                         } else if (token.type == T_IDENTIFIER) {
1628                                 const symbol_t *sym = token.v.symbol;
1629                                 name = sym->string;
1630                         } else {
1631                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1632                                 break;
1633                         }
1634
1635                         next_token();
1636
1637                         int i;
1638                         for(i = 0; i < GNU_AK_LAST; ++i) {
1639                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1640                                         break;
1641                         }
1642                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1643
1644                         attribute = NULL;
1645                         if (kind == GNU_AK_LAST) {
1646                                 if (warning.attribute)
1647                                         warningf(HERE, "'%s' attribute directive ignored", name);
1648
1649                                 /* skip possible arguments */
1650                                 if (token.type == '(') {
1651                                         eat_until_matching_token(')');
1652                                 }
1653                         } else {
1654                                 /* check for arguments */
1655                                 attribute = allocate_gnu_attribute(kind);
1656                                 if (token.type == '(') {
1657                                         next_token();
1658                                         if (token.type == ')') {
1659                                                 /* empty args are allowed */
1660                                                 next_token();
1661                                         } else
1662                                                 attribute->have_arguments = true;
1663                                 }
1664
1665                                 switch(kind) {
1666                                 case GNU_AK_VOLATILE:
1667                                 case GNU_AK_NAKED:
1668                                 case GNU_AK_MALLOC:
1669                                 case GNU_AK_WEAK:
1670                                 case GNU_AK_COMMON:
1671                                 case GNU_AK_NOCOMMON:
1672                                 case GNU_AK_SHARED:
1673                                 case GNU_AK_NOTSHARED:
1674                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1675                                 case GNU_AK_WARN_UNUSED_RESULT:
1676                                 case GNU_AK_LONGCALL:
1677                                 case GNU_AK_SHORTCALL:
1678                                 case GNU_AK_LONG_CALL:
1679                                 case GNU_AK_SHORT_CALL:
1680                                 case GNU_AK_FUNCTION_VECTOR:
1681                                 case GNU_AK_INTERRUPT_HANDLER:
1682                                 case GNU_AK_NMI_HANDLER:
1683                                 case GNU_AK_NESTING:
1684                                 case GNU_AK_NEAR:
1685                                 case GNU_AK_FAR:
1686                                 case GNU_AK_SIGNAL:
1687                                 case GNU_AK_EIGTHBIT_DATA:
1688                                 case GNU_AK_TINY_DATA:
1689                                 case GNU_AK_SAVEALL:
1690                                 case GNU_AK_FLATTEN:
1691                                 case GNU_AK_SSEREGPARM:
1692                                 case GNU_AK_EXTERNALLY_VISIBLE:
1693                                 case GNU_AK_RETURN_TWICE:
1694                                 case GNU_AK_MAY_ALIAS:
1695                                 case GNU_AK_MS_STRUCT:
1696                                 case GNU_AK_GCC_STRUCT:
1697                                         goto no_arg;
1698
1699                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1700                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1701                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1702                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1703                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1704                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1705                                 case GNU_AK_CONST:             modifiers |= DM_CONST;             goto no_arg;
1706                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1707                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1708                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1709                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1710                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1711                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1712                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1713                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1714                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1715                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1716                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1717
1718                                 case GNU_AK_ALIGNED:
1719                                         /* __align__ may be used without an argument */
1720                                         if (attribute->have_arguments) {
1721                                                 parse_gnu_attribute_const_arg(attribute);
1722                                         }
1723                                         break;
1724
1725                                 case GNU_AK_FORMAT_ARG:
1726                                 case GNU_AK_REGPARM:
1727                                 case GNU_AK_TRAP_EXIT:
1728                                         if (!attribute->have_arguments) {
1729                                                 /* should have arguments */
1730                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1731                                                 attribute->invalid = true;
1732                                         } else
1733                                                 parse_gnu_attribute_const_arg(attribute);
1734                                         break;
1735                                 case GNU_AK_ALIAS:
1736                                 case GNU_AK_SECTION:
1737                                 case GNU_AK_SP_SWITCH:
1738                                         if (!attribute->have_arguments) {
1739                                                 /* should have arguments */
1740                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1741                                                 attribute->invalid = true;
1742                                         } else
1743                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1744                                         break;
1745                                 case GNU_AK_FORMAT:
1746                                         if (!attribute->have_arguments) {
1747                                                 /* should have arguments */
1748                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1749                                                 attribute->invalid = true;
1750                                         } else
1751                                                 parse_gnu_attribute_format_args(attribute);
1752                                         break;
1753                                 case GNU_AK_WEAKREF:
1754                                         /* may have one string argument */
1755                                         if (attribute->have_arguments)
1756                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1757                                         break;
1758                                 case GNU_AK_NONNULL:
1759                                         if (attribute->have_arguments)
1760                                                 parse_gnu_attribute_const_arg_list(attribute);
1761                                         break;
1762                                 case GNU_AK_TLS_MODEL:
1763                                         if (!attribute->have_arguments) {
1764                                                 /* should have arguments */
1765                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1766                                         } else
1767                                                 parse_gnu_attribute_tls_model_arg(attribute);
1768                                         break;
1769                                 case GNU_AK_VISIBILITY:
1770                                         if (!attribute->have_arguments) {
1771                                                 /* should have arguments */
1772                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1773                                         } else
1774                                                 parse_gnu_attribute_visibility_arg(attribute);
1775                                         break;
1776                                 case GNU_AK_MODEL:
1777                                         if (!attribute->have_arguments) {
1778                                                 /* should have arguments */
1779                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1780                                         } else {
1781                                                 parse_gnu_attribute_model_arg(attribute);
1782                                         }
1783                                         break;
1784                                 case GNU_AK_MODE:
1785                                         if (!attribute->have_arguments) {
1786                                                 /* should have arguments */
1787                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1788                                         } else {
1789                                                 parse_gnu_attribute_mode_arg(attribute);
1790                                         }
1791                                         break;
1792                                 case GNU_AK_INTERRUPT:
1793                                         /* may have one string argument */
1794                                         if (attribute->have_arguments)
1795                                                 parse_gnu_attribute_interrupt_arg(attribute);
1796                                         break;
1797                                 case GNU_AK_SENTINEL:
1798                                         /* may have one string argument */
1799                                         if (attribute->have_arguments)
1800                                                 parse_gnu_attribute_const_arg(attribute);
1801                                         break;
1802                                 case GNU_AK_LAST:
1803                                         /* already handled */
1804                                         break;
1805
1806 no_arg:
1807                                         check_no_argument(attribute, name);
1808                                 }
1809                         }
1810                         if (attribute != NULL) {
1811                                 if (last != NULL) {
1812                                         last->next = attribute;
1813                                         last       = attribute;
1814                                 } else {
1815                                         head = last = attribute;
1816                                 }
1817                         }
1818
1819                         if (token.type != ',')
1820                                 break;
1821                         next_token();
1822                 }
1823         }
1824         expect(')');
1825         expect(')');
1826 end_error:
1827         *attributes = head;
1828
1829         return modifiers;
1830 }
1831
1832 /**
1833  * Parse GNU attributes.
1834  */
1835 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1836 {
1837         decl_modifiers_t modifiers = 0;
1838
1839         while (true) {
1840                 switch(token.type) {
1841                 case T___attribute__:
1842                         modifiers |= parse_gnu_attribute(attributes);
1843                         continue;
1844
1845                 case T_asm:
1846                         next_token();
1847                         expect('(');
1848                         if (token.type != T_STRING_LITERAL) {
1849                                 parse_error_expected("while parsing assembler attribute",
1850                                                      T_STRING_LITERAL, NULL);
1851                                 eat_until_matching_token('(');
1852                                 break;
1853                         } else {
1854                                 parse_string_literals();
1855                         }
1856                         expect(')');
1857                         continue;
1858
1859                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1860                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1861                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1862
1863                 case T___thiscall:
1864                         /* TODO record modifier */
1865                         warningf(HERE, "Ignoring declaration modifier %K", &token);
1866                         break;
1867
1868 end_error:
1869                 default: return modifiers;
1870                 }
1871
1872                 next_token();
1873         }
1874 }
1875
1876 static void mark_decls_read(expression_t *expr, declaration_t *lhs_decl);
1877
1878 static declaration_t *determine_lhs_decl(expression_t *const expr, declaration_t *lhs_decl)
1879 {
1880         switch (expr->kind) {
1881                 case EXPR_REFERENCE: {
1882                         declaration_t *const decl = expr->reference.declaration;
1883                         return decl;
1884                 }
1885
1886                 case EXPR_ARRAY_ACCESS: {
1887                         expression_t  *const ref  = expr->array_access.array_ref;
1888                         declaration_t *      decl = NULL;
1889                         if (is_type_array(skip_typeref(revert_automatic_type_conversion(ref)))) {
1890                                 decl     = determine_lhs_decl(ref, lhs_decl);
1891                                 lhs_decl = decl;
1892                         } else {
1893                                 mark_decls_read(expr->select.compound, lhs_decl);
1894                         }
1895                         mark_decls_read(expr->array_access.index, lhs_decl);
1896                         return decl;
1897                 }
1898
1899                 case EXPR_SELECT: {
1900                         if (is_type_compound(skip_typeref(expr->base.type))) {
1901                                 return determine_lhs_decl(expr->select.compound, lhs_decl);
1902                         } else {
1903                                 mark_decls_read(expr->select.compound, lhs_decl);
1904                                 return NULL;
1905                         }
1906                 }
1907
1908                 case EXPR_UNARY_DEREFERENCE: {
1909                         expression_t *const val = expr->unary.value;
1910                         if (val->kind == EXPR_UNARY_TAKE_ADDRESS) {
1911                                 /* *&x is a NOP */
1912                                 return determine_lhs_decl(val->unary.value, lhs_decl);
1913                         } else {
1914                                 mark_decls_read(val, NULL);
1915                                 return NULL;
1916                         }
1917                 }
1918
1919                 default:
1920                         mark_decls_read(expr, NULL);
1921                         return NULL;
1922         }
1923 }
1924
1925 #define DECL_ANY ((declaration_t*)-1)
1926
1927 /**
1928  * Mark declarations, which are read.  This is used to deted variables, which
1929  * are never read.
1930  * Example:
1931  * x = x + 1;
1932  *   x is not marked as "read", because it is only read to calculate its own new
1933  *   value.
1934  *
1935  * x += y; y += x;
1936  *   x and y are not detected as "not read", because multiple variables are
1937  *   involved.
1938  */
1939 static void mark_decls_read(expression_t *const expr, declaration_t *lhs_decl)
1940 {
1941         switch (expr->kind) {
1942                 case EXPR_REFERENCE: {
1943                         declaration_t *const decl = expr->reference.declaration;
1944                         if (lhs_decl != decl && lhs_decl != DECL_ANY)
1945                                 decl->read = true;
1946                         return;
1947                 }
1948
1949                 case EXPR_CALL:
1950                         // TODO respect pure/const
1951                         mark_decls_read(expr->call.function, NULL);
1952                         for (call_argument_t *arg = expr->call.arguments; arg != NULL; arg = arg->next) {
1953                                 mark_decls_read(arg->expression, NULL);
1954                         }
1955                         return;
1956
1957                 case EXPR_CONDITIONAL:
1958                         // TODO lhs_decl should depend on whether true/false have an effect
1959                         mark_decls_read(expr->conditional.condition, NULL);
1960                         if (expr->conditional.true_expression != NULL)
1961                                 mark_decls_read(expr->conditional.true_expression, lhs_decl);
1962                         mark_decls_read(expr->conditional.false_expression, lhs_decl);
1963                         return;
1964
1965                 case EXPR_SELECT:
1966                         if (lhs_decl == DECL_ANY && !is_type_compound(skip_typeref(expr->base.type)))
1967                                 lhs_decl = NULL;
1968                         mark_decls_read(expr->select.compound, lhs_decl);
1969                         return;
1970
1971                 case EXPR_ARRAY_ACCESS: {
1972                         expression_t *const ref = expr->array_access.array_ref;
1973                         mark_decls_read(ref, lhs_decl);
1974                         lhs_decl = determine_lhs_decl(ref, lhs_decl);
1975                         mark_decls_read(expr->array_access.index, lhs_decl);
1976                         return;
1977                 }
1978
1979                 case EXPR_VA_ARG:
1980                         mark_decls_read(expr->va_arge.ap, lhs_decl);
1981                         return;
1982
1983                 case EXPR_UNARY_CAST:
1984                         /* Special case: Use void cast to mark a variable as "read" */
1985                         if (is_type_atomic(skip_typeref(expr->base.type), ATOMIC_TYPE_VOID))
1986                                 lhs_decl = NULL;
1987                         goto unary;
1988
1989                 case EXPR_UNARY_DEREFERENCE:
1990                         if (lhs_decl == DECL_ANY)
1991                                 lhs_decl = NULL;
1992                         goto unary;
1993
1994                 case EXPR_UNARY_NEGATE:
1995                 case EXPR_UNARY_PLUS:
1996                 case EXPR_UNARY_BITWISE_NEGATE:
1997                 case EXPR_UNARY_NOT:
1998                 case EXPR_UNARY_TAKE_ADDRESS:
1999                 case EXPR_UNARY_POSTFIX_INCREMENT:
2000                 case EXPR_UNARY_POSTFIX_DECREMENT:
2001                 case EXPR_UNARY_PREFIX_INCREMENT:
2002                 case EXPR_UNARY_PREFIX_DECREMENT:
2003                 case EXPR_UNARY_CAST_IMPLICIT:
2004                 case EXPR_UNARY_ASSUME:
2005 unary:
2006                         mark_decls_read(expr->unary.value, lhs_decl);
2007                         return;
2008
2009                 case EXPR_BINARY_ADD:
2010                 case EXPR_BINARY_SUB:
2011                 case EXPR_BINARY_MUL:
2012                 case EXPR_BINARY_DIV:
2013                 case EXPR_BINARY_MOD:
2014                 case EXPR_BINARY_EQUAL:
2015                 case EXPR_BINARY_NOTEQUAL:
2016                 case EXPR_BINARY_LESS:
2017                 case EXPR_BINARY_LESSEQUAL:
2018                 case EXPR_BINARY_GREATER:
2019                 case EXPR_BINARY_GREATEREQUAL:
2020                 case EXPR_BINARY_BITWISE_AND:
2021                 case EXPR_BINARY_BITWISE_OR:
2022                 case EXPR_BINARY_BITWISE_XOR:
2023                 case EXPR_BINARY_LOGICAL_AND:
2024                 case EXPR_BINARY_LOGICAL_OR:
2025                 case EXPR_BINARY_SHIFTLEFT:
2026                 case EXPR_BINARY_SHIFTRIGHT:
2027                 case EXPR_BINARY_COMMA:
2028                 case EXPR_BINARY_ISGREATER:
2029                 case EXPR_BINARY_ISGREATEREQUAL:
2030                 case EXPR_BINARY_ISLESS:
2031                 case EXPR_BINARY_ISLESSEQUAL:
2032                 case EXPR_BINARY_ISLESSGREATER:
2033                 case EXPR_BINARY_ISUNORDERED:
2034                         mark_decls_read(expr->binary.left,  lhs_decl);
2035                         mark_decls_read(expr->binary.right, lhs_decl);
2036                         return;
2037
2038                 case EXPR_BINARY_ASSIGN:
2039                 case EXPR_BINARY_MUL_ASSIGN:
2040                 case EXPR_BINARY_DIV_ASSIGN:
2041                 case EXPR_BINARY_MOD_ASSIGN:
2042                 case EXPR_BINARY_ADD_ASSIGN:
2043                 case EXPR_BINARY_SUB_ASSIGN:
2044                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:
2045                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
2046                 case EXPR_BINARY_BITWISE_AND_ASSIGN:
2047                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:
2048                 case EXPR_BINARY_BITWISE_OR_ASSIGN: {
2049                         if (lhs_decl == DECL_ANY)
2050                                 lhs_decl = NULL;
2051                         lhs_decl = determine_lhs_decl(expr->binary.left, lhs_decl);
2052                         mark_decls_read(expr->binary.right, lhs_decl);
2053                         return;
2054                 }
2055
2056                 case EXPR_VA_START:
2057                         determine_lhs_decl(expr->va_starte.ap, lhs_decl);
2058                         return;
2059
2060                 case EXPR_UNKNOWN:
2061                 case EXPR_INVALID:
2062                 case EXPR_CONST:
2063                 case EXPR_CHARACTER_CONSTANT:
2064                 case EXPR_WIDE_CHARACTER_CONSTANT:
2065                 case EXPR_STRING_LITERAL:
2066                 case EXPR_WIDE_STRING_LITERAL:
2067                 case EXPR_COMPOUND_LITERAL: // TODO init?
2068                 case EXPR_SIZEOF:
2069                 case EXPR_CLASSIFY_TYPE:
2070                 case EXPR_ALIGNOF:
2071                 case EXPR_FUNCNAME:
2072                 case EXPR_BUILTIN_SYMBOL:
2073                 case EXPR_BUILTIN_CONSTANT_P:
2074                 case EXPR_BUILTIN_PREFETCH:
2075                 case EXPR_OFFSETOF:
2076                 case EXPR_STATEMENT: // TODO
2077                 case EXPR_LABEL_ADDRESS:
2078                 case EXPR_BINARY_BUILTIN_EXPECT:
2079                         return;
2080         }
2081
2082         panic("unhandled expression");
2083 }
2084
2085 static designator_t *parse_designation(void)
2086 {
2087         designator_t *result = NULL;
2088         designator_t *last   = NULL;
2089
2090         while (true) {
2091                 designator_t *designator;
2092                 switch(token.type) {
2093                 case '[':
2094                         designator = allocate_ast_zero(sizeof(designator[0]));
2095                         designator->source_position = token.source_position;
2096                         next_token();
2097                         add_anchor_token(']');
2098                         designator->array_index = parse_constant_expression();
2099                         rem_anchor_token(']');
2100                         expect(']');
2101                         break;
2102                 case '.':
2103                         designator = allocate_ast_zero(sizeof(designator[0]));
2104                         designator->source_position = token.source_position;
2105                         next_token();
2106                         if (token.type != T_IDENTIFIER) {
2107                                 parse_error_expected("while parsing designator",
2108                                                      T_IDENTIFIER, NULL);
2109                                 return NULL;
2110                         }
2111                         designator->symbol = token.v.symbol;
2112                         next_token();
2113                         break;
2114                 default:
2115                         expect('=');
2116                         return result;
2117                 }
2118
2119                 assert(designator != NULL);
2120                 if (last != NULL) {
2121                         last->next = designator;
2122                 } else {
2123                         result = designator;
2124                 }
2125                 last = designator;
2126         }
2127 end_error:
2128         return NULL;
2129 }
2130
2131 static initializer_t *initializer_from_string(array_type_t *type,
2132                                               const string_t *const string)
2133 {
2134         /* TODO: check len vs. size of array type */
2135         (void) type;
2136
2137         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
2138         initializer->string.string = *string;
2139
2140         return initializer;
2141 }
2142
2143 static initializer_t *initializer_from_wide_string(array_type_t *const type,
2144                                                    wide_string_t *const string)
2145 {
2146         /* TODO: check len vs. size of array type */
2147         (void) type;
2148
2149         initializer_t *const initializer =
2150                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
2151         initializer->wide_string.string = *string;
2152
2153         return initializer;
2154 }
2155
2156 /**
2157  * Build an initializer from a given expression.
2158  */
2159 static initializer_t *initializer_from_expression(type_t *orig_type,
2160                                                   expression_t *expression)
2161 {
2162         /* TODO check that expression is a constant expression */
2163
2164         /* Â§ 6.7.8.14/15 char array may be initialized by string literals */
2165         type_t *type           = skip_typeref(orig_type);
2166         type_t *expr_type_orig = expression->base.type;
2167         type_t *expr_type      = skip_typeref(expr_type_orig);
2168         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
2169                 array_type_t *const array_type   = &type->array;
2170                 type_t       *const element_type = skip_typeref(array_type->element_type);
2171
2172                 if (element_type->kind == TYPE_ATOMIC) {
2173                         atomic_type_kind_t akind = element_type->atomic.akind;
2174                         switch (expression->kind) {
2175                                 case EXPR_STRING_LITERAL:
2176                                         if (akind == ATOMIC_TYPE_CHAR
2177                                                         || akind == ATOMIC_TYPE_SCHAR
2178                                                         || akind == ATOMIC_TYPE_UCHAR) {
2179                                                 return initializer_from_string(array_type,
2180                                                         &expression->string.value);
2181                                         }
2182
2183                                 case EXPR_WIDE_STRING_LITERAL: {
2184                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
2185                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
2186                                                 return initializer_from_wide_string(array_type,
2187                                                         &expression->wide_string.value);
2188                                         }
2189                                 }
2190
2191                                 default:
2192                                         break;
2193                         }
2194                 }
2195         }
2196
2197         assign_error_t error = semantic_assign(type, expression);
2198         if (error == ASSIGN_ERROR_INCOMPATIBLE)
2199                 return NULL;
2200         report_assign_error(error, type, expression, "initializer",
2201                             &expression->base.source_position);
2202
2203         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
2204 #if 0
2205         if (type->kind == TYPE_BITFIELD) {
2206                 type = type->bitfield.base_type;
2207         }
2208 #endif
2209         result->value.value = create_implicit_cast(expression, type);
2210
2211         return result;
2212 }
2213
2214 /**
2215  * Checks if a given expression can be used as an constant initializer.
2216  */
2217 static bool is_initializer_constant(const expression_t *expression)
2218 {
2219         return is_constant_expression(expression)
2220                 || is_address_constant(expression);
2221 }
2222
2223 /**
2224  * Parses an scalar initializer.
2225  *
2226  * Â§ 6.7.8.11; eat {} without warning
2227  */
2228 static initializer_t *parse_scalar_initializer(type_t *type,
2229                                                bool must_be_constant)
2230 {
2231         /* there might be extra {} hierarchies */
2232         int braces = 0;
2233         if (token.type == '{') {
2234                 warningf(HERE, "extra curly braces around scalar initializer");
2235                 do {
2236                         ++braces;
2237                         next_token();
2238                 } while (token.type == '{');
2239         }
2240
2241         expression_t *expression = parse_assignment_expression();
2242         mark_decls_read(expression, NULL);
2243         if (must_be_constant && !is_initializer_constant(expression)) {
2244                 errorf(&expression->base.source_position,
2245                        "Initialisation expression '%E' is not constant\n",
2246                        expression);
2247         }
2248
2249         initializer_t *initializer = initializer_from_expression(type, expression);
2250
2251         if (initializer == NULL) {
2252                 errorf(&expression->base.source_position,
2253                        "expression '%E' (type '%T') doesn't match expected type '%T'",
2254                        expression, expression->base.type, type);
2255                 /* TODO */
2256                 return NULL;
2257         }
2258
2259         bool additional_warning_displayed = false;
2260         while (braces > 0) {
2261                 if (token.type == ',') {
2262                         next_token();
2263                 }
2264                 if (token.type != '}') {
2265                         if (!additional_warning_displayed) {
2266                                 warningf(HERE, "additional elements in scalar initializer");
2267                                 additional_warning_displayed = true;
2268                         }
2269                 }
2270                 eat_block();
2271                 braces--;
2272         }
2273
2274         return initializer;
2275 }
2276
2277 /**
2278  * An entry in the type path.
2279  */
2280 typedef struct type_path_entry_t type_path_entry_t;
2281 struct type_path_entry_t {
2282         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2283         union {
2284                 size_t         index;          /**< For array types: the current index. */
2285                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2286         } v;
2287 };
2288
2289 /**
2290  * A type path expression a position inside compound or array types.
2291  */
2292 typedef struct type_path_t type_path_t;
2293 struct type_path_t {
2294         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2295         type_t            *top_type;     /**< type of the element the path points */
2296         size_t             max_index;    /**< largest index in outermost array */
2297 };
2298
2299 /**
2300  * Prints a type path for debugging.
2301  */
2302 static __attribute__((unused)) void debug_print_type_path(
2303                 const type_path_t *path)
2304 {
2305         size_t len = ARR_LEN(path->path);
2306
2307         for(size_t i = 0; i < len; ++i) {
2308                 const type_path_entry_t *entry = & path->path[i];
2309
2310                 type_t *type = skip_typeref(entry->type);
2311                 if (is_type_compound(type)) {
2312                         /* in gcc mode structs can have no members */
2313                         if (entry->v.compound_entry == NULL) {
2314                                 assert(i == len-1);
2315                                 continue;
2316                         }
2317                         fprintf(stderr, ".%s", entry->v.compound_entry->symbol->string);
2318                 } else if (is_type_array(type)) {
2319                         fprintf(stderr, "[%zu]", entry->v.index);
2320                 } else {
2321                         fprintf(stderr, "-INVALID-");
2322                 }
2323         }
2324         if (path->top_type != NULL) {
2325                 fprintf(stderr, "  (");
2326                 print_type(path->top_type);
2327                 fprintf(stderr, ")");
2328         }
2329 }
2330
2331 /**
2332  * Return the top type path entry, ie. in a path
2333  * (type).a.b returns the b.
2334  */
2335 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2336 {
2337         size_t len = ARR_LEN(path->path);
2338         assert(len > 0);
2339         return &path->path[len-1];
2340 }
2341
2342 /**
2343  * Enlarge the type path by an (empty) element.
2344  */
2345 static type_path_entry_t *append_to_type_path(type_path_t *path)
2346 {
2347         size_t len = ARR_LEN(path->path);
2348         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2349
2350         type_path_entry_t *result = & path->path[len];
2351         memset(result, 0, sizeof(result[0]));
2352         return result;
2353 }
2354
2355 /**
2356  * Descending into a sub-type. Enter the scope of the current
2357  * top_type.
2358  */
2359 static void descend_into_subtype(type_path_t *path)
2360 {
2361         type_t *orig_top_type = path->top_type;
2362         type_t *top_type      = skip_typeref(orig_top_type);
2363
2364         type_path_entry_t *top = append_to_type_path(path);
2365         top->type              = top_type;
2366
2367         if (is_type_compound(top_type)) {
2368                 declaration_t *declaration = top_type->compound.declaration;
2369                 declaration_t *entry       = declaration->scope.declarations;
2370                 top->v.compound_entry      = entry;
2371
2372                 if (entry != NULL) {
2373                         path->top_type         = entry->type;
2374                 } else {
2375                         path->top_type         = NULL;
2376                 }
2377         } else if (is_type_array(top_type)) {
2378                 top->v.index   = 0;
2379                 path->top_type = top_type->array.element_type;
2380         } else {
2381                 assert(!is_type_valid(top_type));
2382         }
2383 }
2384
2385 /**
2386  * Pop an entry from the given type path, ie. returning from
2387  * (type).a.b to (type).a
2388  */
2389 static void ascend_from_subtype(type_path_t *path)
2390 {
2391         type_path_entry_t *top = get_type_path_top(path);
2392
2393         path->top_type = top->type;
2394
2395         size_t len = ARR_LEN(path->path);
2396         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2397 }
2398
2399 /**
2400  * Pop entries from the given type path until the given
2401  * path level is reached.
2402  */
2403 static void ascend_to(type_path_t *path, size_t top_path_level)
2404 {
2405         size_t len = ARR_LEN(path->path);
2406
2407         while (len > top_path_level) {
2408                 ascend_from_subtype(path);
2409                 len = ARR_LEN(path->path);
2410         }
2411 }
2412
2413 static bool walk_designator(type_path_t *path, const designator_t *designator,
2414                             bool used_in_offsetof)
2415 {
2416         for( ; designator != NULL; designator = designator->next) {
2417                 type_path_entry_t *top       = get_type_path_top(path);
2418                 type_t            *orig_type = top->type;
2419
2420                 type_t *type = skip_typeref(orig_type);
2421
2422                 if (designator->symbol != NULL) {
2423                         symbol_t *symbol = designator->symbol;
2424                         if (!is_type_compound(type)) {
2425                                 if (is_type_valid(type)) {
2426                                         errorf(&designator->source_position,
2427                                                "'.%Y' designator used for non-compound type '%T'",
2428                                                symbol, orig_type);
2429                                 }
2430
2431                                 top->type             = type_error_type;
2432                                 top->v.compound_entry = NULL;
2433                                 orig_type             = type_error_type;
2434                         } else {
2435                                 declaration_t *declaration = type->compound.declaration;
2436                                 declaration_t *iter        = declaration->scope.declarations;
2437                                 for( ; iter != NULL; iter = iter->next) {
2438                                         if (iter->symbol == symbol) {
2439                                                 break;
2440                                         }
2441                                 }
2442                                 if (iter == NULL) {
2443                                         errorf(&designator->source_position,
2444                                                "'%T' has no member named '%Y'", orig_type, symbol);
2445                                         goto failed;
2446                                 }
2447                                 if (used_in_offsetof) {
2448                                         type_t *real_type = skip_typeref(iter->type);
2449                                         if (real_type->kind == TYPE_BITFIELD) {
2450                                                 errorf(&designator->source_position,
2451                                                        "offsetof designator '%Y' may not specify bitfield",
2452                                                        symbol);
2453                                                 goto failed;
2454                                         }
2455                                 }
2456
2457                                 top->type             = orig_type;
2458                                 top->v.compound_entry = iter;
2459                                 orig_type             = iter->type;
2460                         }
2461                 } else {
2462                         expression_t *array_index = designator->array_index;
2463                         assert(designator->array_index != NULL);
2464
2465                         if (!is_type_array(type)) {
2466                                 if (is_type_valid(type)) {
2467                                         errorf(&designator->source_position,
2468                                                "[%E] designator used for non-array type '%T'",
2469                                                array_index, orig_type);
2470                                 }
2471                                 goto failed;
2472                         }
2473
2474                         long index = fold_constant(array_index);
2475                         if (!used_in_offsetof) {
2476                                 if (index < 0) {
2477                                         errorf(&designator->source_position,
2478                                                "array index [%E] must be positive", array_index);
2479                                 } else if (type->array.size_constant) {
2480                                         long array_size = type->array.size;
2481                                         if (index >= array_size) {
2482                                                 errorf(&designator->source_position,
2483                                                        "designator [%E] (%d) exceeds array size %d",
2484                                                        array_index, index, array_size);
2485                                         }
2486                                 }
2487                         }
2488
2489                         top->type    = orig_type;
2490                         top->v.index = (size_t) index;
2491                         orig_type    = type->array.element_type;
2492                 }
2493                 path->top_type = orig_type;
2494
2495                 if (designator->next != NULL) {
2496                         descend_into_subtype(path);
2497                 }
2498         }
2499         return true;
2500
2501 failed:
2502         return false;
2503 }
2504
2505 static void advance_current_object(type_path_t *path, size_t top_path_level)
2506 {
2507         type_path_entry_t *top = get_type_path_top(path);
2508
2509         type_t *type = skip_typeref(top->type);
2510         if (is_type_union(type)) {
2511                 /* in unions only the first element is initialized */
2512                 top->v.compound_entry = NULL;
2513         } else if (is_type_struct(type)) {
2514                 declaration_t *entry = top->v.compound_entry;
2515
2516                 entry                 = entry->next;
2517                 top->v.compound_entry = entry;
2518                 if (entry != NULL) {
2519                         path->top_type = entry->type;
2520                         return;
2521                 }
2522         } else if (is_type_array(type)) {
2523                 assert(is_type_array(type));
2524
2525                 top->v.index++;
2526
2527                 if (!type->array.size_constant || top->v.index < type->array.size) {
2528                         return;
2529                 }
2530         } else {
2531                 assert(!is_type_valid(type));
2532                 return;
2533         }
2534
2535         /* we're past the last member of the current sub-aggregate, try if we
2536          * can ascend in the type hierarchy and continue with another subobject */
2537         size_t len = ARR_LEN(path->path);
2538
2539         if (len > top_path_level) {
2540                 ascend_from_subtype(path);
2541                 advance_current_object(path, top_path_level);
2542         } else {
2543                 path->top_type = NULL;
2544         }
2545 }
2546
2547 /**
2548  * skip until token is found.
2549  */
2550 static void skip_until(int type)
2551 {
2552         while (token.type != type) {
2553                 if (token.type == T_EOF)
2554                         return;
2555                 next_token();
2556         }
2557 }
2558
2559 /**
2560  * skip any {...} blocks until a closing bracket is reached.
2561  */
2562 static void skip_initializers(void)
2563 {
2564         if (token.type == '{')
2565                 next_token();
2566
2567         while (token.type != '}') {
2568                 if (token.type == T_EOF)
2569                         return;
2570                 if (token.type == '{') {
2571                         eat_block();
2572                         continue;
2573                 }
2574                 next_token();
2575         }
2576 }
2577
2578 static initializer_t *create_empty_initializer(void)
2579 {
2580         static initializer_t empty_initializer
2581                 = { .list = { { INITIALIZER_LIST }, 0 } };
2582         return &empty_initializer;
2583 }
2584
2585 /**
2586  * Parse a part of an initialiser for a struct or union,
2587  */
2588 static initializer_t *parse_sub_initializer(type_path_t *path,
2589                 type_t *outer_type, size_t top_path_level,
2590                 parse_initializer_env_t *env)
2591 {
2592         if (token.type == '}') {
2593                 /* empty initializer */
2594                 return create_empty_initializer();
2595         }
2596
2597         type_t *orig_type = path->top_type;
2598         type_t *type      = NULL;
2599
2600         if (orig_type == NULL) {
2601                 /* We are initializing an empty compound. */
2602         } else {
2603                 type = skip_typeref(orig_type);
2604         }
2605
2606         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2607
2608         while (true) {
2609                 designator_t *designator = NULL;
2610                 if (token.type == '.' || token.type == '[') {
2611                         designator = parse_designation();
2612                         goto finish_designator;
2613                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2614                         /* GNU-style designator ("identifier: value") */
2615                         designator = allocate_ast_zero(sizeof(designator[0]));
2616                         designator->source_position = token.source_position;
2617                         designator->symbol          = token.v.symbol;
2618                         eat(T_IDENTIFIER);
2619                         eat(':');
2620
2621 finish_designator:
2622                         /* reset path to toplevel, evaluate designator from there */
2623                         ascend_to(path, top_path_level);
2624                         if (!walk_designator(path, designator, false)) {
2625                                 /* can't continue after designation error */
2626                                 goto end_error;
2627                         }
2628
2629                         initializer_t *designator_initializer
2630                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2631                         designator_initializer->designator.designator = designator;
2632                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2633
2634                         orig_type = path->top_type;
2635                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2636                 }
2637
2638                 initializer_t *sub;
2639
2640                 if (token.type == '{') {
2641                         if (type != NULL && is_type_scalar(type)) {
2642                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2643                         } else {
2644                                 eat('{');
2645                                 if (type == NULL) {
2646                                         if (env->declaration != NULL) {
2647                                                 errorf(HERE, "extra brace group at end of initializer for '%Y'",
2648                                                        env->declaration->symbol);
2649                                         } else {
2650                                                 errorf(HERE, "extra brace group at end of initializer");
2651                                         }
2652                                 } else
2653                                         descend_into_subtype(path);
2654
2655                                 add_anchor_token('}');
2656                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2657                                                             env);
2658                                 rem_anchor_token('}');
2659
2660                                 if (type != NULL) {
2661                                         ascend_from_subtype(path);
2662                                         expect('}');
2663                                 } else {
2664                                         expect('}');
2665                                         goto error_parse_next;
2666                                 }
2667                         }
2668                 } else {
2669                         /* must be an expression */
2670                         expression_t *expression = parse_assignment_expression();
2671
2672                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2673                                 errorf(&expression->base.source_position,
2674                                        "Initialisation expression '%E' is not constant\n",
2675                                        expression);
2676                         }
2677
2678                         if (type == NULL) {
2679                                 /* we are already outside, ... */
2680                                 type_t *const outer_type_skip = skip_typeref(outer_type);
2681                                 if (is_type_compound(outer_type_skip) &&
2682                                     !outer_type_skip->compound.declaration->init.complete) {
2683                                         goto error_parse_next;
2684                                 }
2685                                 goto error_excess;
2686                         }
2687
2688                         /* handle { "string" } special case */
2689                         if ((expression->kind == EXPR_STRING_LITERAL
2690                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2691                                         && outer_type != NULL) {
2692                                 sub = initializer_from_expression(outer_type, expression);
2693                                 if (sub != NULL) {
2694                                         if (token.type == ',') {
2695                                                 next_token();
2696                                         }
2697                                         if (token.type != '}') {
2698                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2699                                                                  orig_type);
2700                                         }
2701                                         /* TODO: eat , ... */
2702                                         return sub;
2703                                 }
2704                         }
2705
2706                         /* descend into subtypes until expression matches type */
2707                         while (true) {
2708                                 orig_type = path->top_type;
2709                                 type      = skip_typeref(orig_type);
2710
2711                                 sub = initializer_from_expression(orig_type, expression);
2712                                 if (sub != NULL) {
2713                                         break;
2714                                 }
2715                                 if (!is_type_valid(type)) {
2716                                         goto end_error;
2717                                 }
2718                                 if (is_type_scalar(type)) {
2719                                         errorf(&expression->base.source_position,
2720                                                         "expression '%E' doesn't match expected type '%T'",
2721                                                         expression, orig_type);
2722                                         goto end_error;
2723                                 }
2724
2725                                 descend_into_subtype(path);
2726                         }
2727                 }
2728
2729                 /* update largest index of top array */
2730                 const type_path_entry_t *first      = &path->path[0];
2731                 type_t                  *first_type = first->type;
2732                 first_type                          = skip_typeref(first_type);
2733                 if (is_type_array(first_type)) {
2734                         size_t index = first->v.index;
2735                         if (index > path->max_index)
2736                                 path->max_index = index;
2737                 }
2738
2739                 if (type != NULL) {
2740                         /* append to initializers list */
2741                         ARR_APP1(initializer_t*, initializers, sub);
2742                 } else {
2743 error_excess:
2744                         if (env->declaration != NULL)
2745                                 warningf(HERE, "excess elements in struct initializer for '%Y'",
2746                                  env->declaration->symbol);
2747                         else
2748                                 warningf(HERE, "excess elements in struct initializer");
2749                 }
2750
2751 error_parse_next:
2752                 if (token.type == '}') {
2753                         break;
2754                 }
2755                 expect(',');
2756                 if (token.type == '}') {
2757                         break;
2758                 }
2759
2760                 if (type != NULL) {
2761                         /* advance to the next declaration if we are not at the end */
2762                         advance_current_object(path, top_path_level);
2763                         orig_type = path->top_type;
2764                         if (orig_type != NULL)
2765                                 type = skip_typeref(orig_type);
2766                         else
2767                                 type = NULL;
2768                 }
2769         }
2770
2771         size_t len  = ARR_LEN(initializers);
2772         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2773         initializer_t *result = allocate_ast_zero(size);
2774         result->kind          = INITIALIZER_LIST;
2775         result->list.len      = len;
2776         memcpy(&result->list.initializers, initializers,
2777                len * sizeof(initializers[0]));
2778
2779         DEL_ARR_F(initializers);
2780         ascend_to(path, top_path_level+1);
2781
2782         return result;
2783
2784 end_error:
2785         skip_initializers();
2786         DEL_ARR_F(initializers);
2787         ascend_to(path, top_path_level+1);
2788         return NULL;
2789 }
2790
2791 /**
2792  * Parses an initializer. Parsers either a compound literal
2793  * (env->declaration == NULL) or an initializer of a declaration.
2794  */
2795 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2796 {
2797         type_t        *type   = skip_typeref(env->type);
2798         initializer_t *result = NULL;
2799         size_t         max_index;
2800
2801         if (is_type_scalar(type)) {
2802                 result = parse_scalar_initializer(type, env->must_be_constant);
2803         } else if (token.type == '{') {
2804                 eat('{');
2805
2806                 type_path_t path;
2807                 memset(&path, 0, sizeof(path));
2808                 path.top_type = env->type;
2809                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2810
2811                 descend_into_subtype(&path);
2812
2813                 add_anchor_token('}');
2814                 result = parse_sub_initializer(&path, env->type, 1, env);
2815                 rem_anchor_token('}');
2816
2817                 max_index = path.max_index;
2818                 DEL_ARR_F(path.path);
2819
2820                 expect('}');
2821         } else {
2822                 /* parse_scalar_initializer() also works in this case: we simply
2823                  * have an expression without {} around it */
2824                 result = parse_scalar_initializer(type, env->must_be_constant);
2825         }
2826
2827         /* Â§ 6.7.5 (22)  array initializers for arrays with unknown size determine
2828          * the array type size */
2829         if (is_type_array(type) && type->array.size_expression == NULL
2830                         && result != NULL) {
2831                 size_t size;
2832                 switch (result->kind) {
2833                 case INITIALIZER_LIST:
2834                         size = max_index + 1;
2835                         break;
2836
2837                 case INITIALIZER_STRING:
2838                         size = result->string.string.size;
2839                         break;
2840
2841                 case INITIALIZER_WIDE_STRING:
2842                         size = result->wide_string.string.size;
2843                         break;
2844
2845                 case INITIALIZER_DESIGNATOR:
2846                 case INITIALIZER_VALUE:
2847                         /* can happen for parse errors */
2848                         size = 0;
2849                         break;
2850
2851                 default:
2852                         internal_errorf(HERE, "invalid initializer type");
2853                 }
2854
2855                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2856                 cnst->base.type          = type_size_t;
2857                 cnst->conste.v.int_value = size;
2858
2859                 type_t *new_type = duplicate_type(type);
2860
2861                 new_type->array.size_expression = cnst;
2862                 new_type->array.size_constant   = true;
2863                 new_type->array.size            = size;
2864                 env->type = new_type;
2865         }
2866
2867         return result;
2868 end_error:
2869         return NULL;
2870 }
2871
2872 static declaration_t *append_declaration(declaration_t *declaration);
2873
2874 static declaration_t *parse_compound_type_specifier(bool is_struct)
2875 {
2876         gnu_attribute_t  *attributes = NULL;
2877         decl_modifiers_t  modifiers  = 0;
2878         if (is_struct) {
2879                 eat(T_struct);
2880         } else {
2881                 eat(T_union);
2882         }
2883
2884         symbol_t      *symbol      = NULL;
2885         declaration_t *declaration = NULL;
2886
2887         if (token.type == T___attribute__) {
2888                 modifiers |= parse_attributes(&attributes);
2889         }
2890
2891         if (token.type == T_IDENTIFIER) {
2892                 symbol = token.v.symbol;
2893                 next_token();
2894
2895                 namespace_t const namespc =
2896                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
2897                 declaration = get_declaration(symbol, namespc);
2898                 if (declaration != NULL) {
2899                         if (declaration->parent_scope != scope &&
2900                             (token.type == '{' || token.type == ';')) {
2901                                 declaration = NULL;
2902                         } else if (declaration->init.complete &&
2903                                    token.type == '{') {
2904                                 assert(symbol != NULL);
2905                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition at %P)",
2906                                        is_struct ? "struct" : "union", symbol,
2907                                        &declaration->source_position);
2908                                 declaration->scope.declarations = NULL;
2909                         }
2910                 }
2911         } else if (token.type != '{') {
2912                 if (is_struct) {
2913                         parse_error_expected("while parsing struct type specifier",
2914                                              T_IDENTIFIER, '{', NULL);
2915                 } else {
2916                         parse_error_expected("while parsing union type specifier",
2917                                              T_IDENTIFIER, '{', NULL);
2918                 }
2919
2920                 return NULL;
2921         }
2922
2923         if (declaration == NULL) {
2924                 declaration = allocate_declaration_zero();
2925                 declaration->namespc         =
2926                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
2927                 declaration->source_position = token.source_position;
2928                 declaration->symbol          = symbol;
2929                 declaration->parent_scope    = scope;
2930                 if (symbol != NULL) {
2931                         environment_push(declaration);
2932                 }
2933                 append_declaration(declaration);
2934         }
2935
2936         if (token.type == '{') {
2937                 declaration->init.complete = true;
2938
2939                 parse_compound_type_entries(declaration);
2940                 modifiers |= parse_attributes(&attributes);
2941         }
2942
2943         declaration->modifiers |= modifiers;
2944         return declaration;
2945 }
2946
2947 static void parse_enum_entries(type_t *const enum_type)
2948 {
2949         eat('{');
2950
2951         if (token.type == '}') {
2952                 next_token();
2953                 errorf(HERE, "empty enum not allowed");
2954                 return;
2955         }
2956
2957         add_anchor_token('}');
2958         do {
2959                 if (token.type != T_IDENTIFIER) {
2960                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
2961                         eat_block();
2962                         rem_anchor_token('}');
2963                         return;
2964                 }
2965
2966                 declaration_t *const entry = allocate_declaration_zero();
2967                 entry->storage_class   = STORAGE_CLASS_ENUM_ENTRY;
2968                 entry->type            = enum_type;
2969                 entry->symbol          = token.v.symbol;
2970                 entry->source_position = token.source_position;
2971                 next_token();
2972
2973                 if (token.type == '=') {
2974                         next_token();
2975                         expression_t *value = parse_constant_expression();
2976
2977                         value = create_implicit_cast(value, enum_type);
2978                         entry->init.enum_value = value;
2979
2980                         /* TODO semantic */
2981                 }
2982
2983                 record_declaration(entry, false);
2984
2985                 if (token.type != ',')
2986                         break;
2987                 next_token();
2988         } while (token.type != '}');
2989         rem_anchor_token('}');
2990
2991         expect('}');
2992
2993 end_error:
2994         ;
2995 }
2996
2997 static type_t *parse_enum_specifier(void)
2998 {
2999         gnu_attribute_t *attributes = NULL;
3000         declaration_t   *declaration;
3001         symbol_t        *symbol;
3002
3003         eat(T_enum);
3004         if (token.type == T_IDENTIFIER) {
3005                 symbol = token.v.symbol;
3006                 next_token();
3007
3008                 declaration = get_declaration(symbol, NAMESPACE_ENUM);
3009         } else if (token.type != '{') {
3010                 parse_error_expected("while parsing enum type specifier",
3011                                      T_IDENTIFIER, '{', NULL);
3012                 return NULL;
3013         } else {
3014                 declaration = NULL;
3015                 symbol      = NULL;
3016         }
3017
3018         if (declaration == NULL) {
3019                 declaration = allocate_declaration_zero();
3020                 declaration->namespc         = NAMESPACE_ENUM;
3021                 declaration->source_position = token.source_position;
3022                 declaration->symbol          = symbol;
3023                 declaration->parent_scope  = scope;
3024         }
3025
3026         type_t *const type      = allocate_type_zero(TYPE_ENUM, &declaration->source_position);
3027         type->enumt.declaration = declaration;
3028
3029         if (token.type == '{') {
3030                 if (declaration->init.complete) {
3031                         errorf(HERE, "multiple definitions of enum %Y", symbol);
3032                 }
3033                 if (symbol != NULL) {
3034                         environment_push(declaration);
3035                 }
3036                 append_declaration(declaration);
3037                 declaration->init.complete = true;
3038
3039                 parse_enum_entries(type);
3040                 parse_attributes(&attributes);
3041         }
3042
3043         return type;
3044 }
3045
3046 /**
3047  * if a symbol is a typedef to another type, return true
3048  */
3049 static bool is_typedef_symbol(symbol_t *symbol)
3050 {
3051         const declaration_t *const declaration =
3052                 get_declaration(symbol, NAMESPACE_NORMAL);
3053         return
3054                 declaration != NULL &&
3055                 declaration->storage_class == STORAGE_CLASS_TYPEDEF;
3056 }
3057
3058 static type_t *parse_typeof(void)
3059 {
3060         eat(T___typeof__);
3061
3062         type_t *type;
3063
3064         expect('(');
3065         add_anchor_token(')');
3066
3067         expression_t *expression  = NULL;
3068
3069         bool old_type_prop     = in_type_prop;
3070         bool old_gcc_extension = in_gcc_extension;
3071         in_type_prop           = true;
3072
3073         while (token.type == T___extension__) {
3074                 /* This can be a prefix to a typename or an expression. */
3075                 next_token();
3076                 in_gcc_extension = true;
3077         }
3078         switch (token.type) {
3079         case T_IDENTIFIER:
3080                 if (is_typedef_symbol(token.v.symbol)) {
3081                         type = parse_typename();
3082                 } else {
3083                         expression = parse_expression();
3084                         type       = expression->base.type;
3085                 }
3086                 break;
3087
3088         TYPENAME_START
3089                 type = parse_typename();
3090                 break;
3091
3092         default:
3093                 expression = parse_expression();
3094                 type       = expression->base.type;
3095                 break;
3096         }
3097         in_type_prop     = old_type_prop;
3098         in_gcc_extension = old_gcc_extension;
3099
3100         rem_anchor_token(')');
3101         expect(')');
3102
3103         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF, &expression->base.source_position);
3104         typeof_type->typeoft.expression  = expression;
3105         typeof_type->typeoft.typeof_type = type;
3106
3107         return typeof_type;
3108 end_error:
3109         return NULL;
3110 }
3111
3112 typedef enum specifiers_t {
3113         SPECIFIER_SIGNED    = 1 << 0,
3114         SPECIFIER_UNSIGNED  = 1 << 1,
3115         SPECIFIER_LONG      = 1 << 2,
3116         SPECIFIER_INT       = 1 << 3,
3117         SPECIFIER_DOUBLE    = 1 << 4,
3118         SPECIFIER_CHAR      = 1 << 5,
3119         SPECIFIER_SHORT     = 1 << 6,
3120         SPECIFIER_LONG_LONG = 1 << 7,
3121         SPECIFIER_FLOAT     = 1 << 8,
3122         SPECIFIER_BOOL      = 1 << 9,
3123         SPECIFIER_VOID      = 1 << 10,
3124         SPECIFIER_INT8      = 1 << 11,
3125         SPECIFIER_INT16     = 1 << 12,
3126         SPECIFIER_INT32     = 1 << 13,
3127         SPECIFIER_INT64     = 1 << 14,
3128         SPECIFIER_INT128    = 1 << 15,
3129         SPECIFIER_COMPLEX   = 1 << 16,
3130         SPECIFIER_IMAGINARY = 1 << 17,
3131 } specifiers_t;
3132
3133 static type_t *create_builtin_type(symbol_t *const symbol,
3134                                    type_t *const real_type)
3135 {
3136         type_t *type            = allocate_type_zero(TYPE_BUILTIN, &builtin_source_position);
3137         type->builtin.symbol    = symbol;
3138         type->builtin.real_type = real_type;
3139
3140         type_t *result = typehash_insert(type);
3141         if (type != result) {
3142                 free_type(type);
3143         }
3144
3145         return result;
3146 }
3147
3148 static type_t *get_typedef_type(symbol_t *symbol)
3149 {
3150         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
3151         if (declaration == NULL ||
3152            declaration->storage_class != STORAGE_CLASS_TYPEDEF)
3153                 return NULL;
3154
3155         type_t *type               = allocate_type_zero(TYPE_TYPEDEF, &declaration->source_position);
3156         type->typedeft.declaration = declaration;
3157
3158         return type;
3159 }
3160
3161 /**
3162  * check for the allowed MS alignment values.
3163  */
3164 static bool check_alignment_value(long long intvalue)
3165 {
3166         if (intvalue < 1 || intvalue > 8192) {
3167                 errorf(HERE, "illegal alignment value");
3168                 return false;
3169         }
3170         unsigned v = (unsigned)intvalue;
3171         for (unsigned i = 1; i <= 8192; i += i) {
3172                 if (i == v)
3173                         return true;
3174         }
3175         errorf(HERE, "alignment must be power of two");
3176         return false;
3177 }
3178
3179 #define DET_MOD(name, tag) do { \
3180         if (*modifiers & tag) warningf(HERE, #name " used more than once"); \
3181         *modifiers |= tag; \
3182 } while (0)
3183
3184 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
3185 {
3186         decl_modifiers_t *modifiers = &specifiers->modifiers;
3187
3188         while (true) {
3189                 if (token.type == T_restrict) {
3190                         next_token();
3191                         DET_MOD(restrict, DM_RESTRICT);
3192                         goto end_loop;
3193                 } else if (token.type != T_IDENTIFIER)
3194                         break;
3195                 symbol_t *symbol = token.v.symbol;
3196                 if (symbol == sym_align) {
3197                         next_token();
3198                         expect('(');
3199                         if (token.type != T_INTEGER)
3200                                 goto end_error;
3201                         if (check_alignment_value(token.v.intvalue)) {
3202                                 if (specifiers->alignment != 0)
3203                                         warningf(HERE, "align used more than once");
3204                                 specifiers->alignment = (unsigned char)token.v.intvalue;
3205                         }
3206                         next_token();
3207                         expect(')');
3208                 } else if (symbol == sym_allocate) {
3209                         next_token();
3210                         expect('(');
3211                         if (token.type != T_IDENTIFIER)
3212                                 goto end_error;
3213                         (void)token.v.symbol;
3214                         expect(')');
3215                 } else if (symbol == sym_dllimport) {
3216                         next_token();
3217                         DET_MOD(dllimport, DM_DLLIMPORT);
3218                 } else if (symbol == sym_dllexport) {
3219                         next_token();
3220                         DET_MOD(dllexport, DM_DLLEXPORT);
3221                 } else if (symbol == sym_thread) {
3222                         next_token();
3223                         DET_MOD(thread, DM_THREAD);
3224                 } else if (symbol == sym_naked) {
3225                         next_token();
3226                         DET_MOD(naked, DM_NAKED);
3227                 } else if (symbol == sym_noinline) {
3228                         next_token();
3229                         DET_MOD(noinline, DM_NOINLINE);
3230                 } else if (symbol == sym_noreturn) {
3231                         next_token();
3232                         DET_MOD(noreturn, DM_NORETURN);
3233                 } else if (symbol == sym_nothrow) {
3234                         next_token();
3235                         DET_MOD(nothrow, DM_NOTHROW);
3236                 } else if (symbol == sym_novtable) {
3237                         next_token();
3238                         DET_MOD(novtable, DM_NOVTABLE);
3239                 } else if (symbol == sym_property) {
3240                         next_token();
3241                         expect('(');
3242                         for (;;) {
3243                                 bool is_get = false;
3244                                 if (token.type != T_IDENTIFIER)
3245                                         goto end_error;
3246                                 if (token.v.symbol == sym_get) {
3247                                         is_get = true;
3248                                 } else if (token.v.symbol == sym_put) {
3249                                 } else {
3250                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
3251                                         goto end_error;
3252                                 }
3253                                 next_token();
3254                                 expect('=');
3255                                 if (token.type != T_IDENTIFIER)
3256                                         goto end_error;
3257                                 if (is_get) {
3258                                         if (specifiers->get_property_sym != NULL) {
3259                                                 errorf(HERE, "get property name already specified");
3260                                         } else {
3261                                                 specifiers->get_property_sym = token.v.symbol;
3262                                         }
3263                                 } else {
3264                                         if (specifiers->put_property_sym != NULL) {
3265                                                 errorf(HERE, "put property name already specified");
3266                                         } else {
3267                                                 specifiers->put_property_sym = token.v.symbol;
3268                                         }
3269                                 }
3270                                 next_token();
3271                                 if (token.type == ',') {
3272                                         next_token();
3273                                         continue;
3274                                 }
3275                                 break;
3276                         }
3277                         expect(')');
3278                 } else if (symbol == sym_selectany) {
3279                         next_token();
3280                         DET_MOD(selectany, DM_SELECTANY);
3281                 } else if (symbol == sym_uuid) {
3282                         next_token();
3283                         expect('(');
3284                         if (token.type != T_STRING_LITERAL)
3285                                 goto end_error;
3286                         next_token();
3287                         expect(')');
3288                 } else if (symbol == sym_deprecated) {
3289                         next_token();
3290                         if (specifiers->deprecated != 0)
3291                                 warningf(HERE, "deprecated used more than once");
3292                         specifiers->deprecated = 1;
3293                         if (token.type == '(') {
3294                                 next_token();
3295                                 if (token.type == T_STRING_LITERAL) {
3296                                         specifiers->deprecated_string = token.v.string.begin;
3297                                         next_token();
3298                                 } else {
3299                                         errorf(HERE, "string literal expected");
3300                                 }
3301                                 expect(')');
3302                         }
3303                 } else if (symbol == sym_noalias) {
3304                         next_token();
3305                         DET_MOD(noalias, DM_NOALIAS);
3306                 } else {
3307                         warningf(HERE, "Unknown modifier %Y ignored", token.v.symbol);
3308                         next_token();
3309                         if (token.type == '(')
3310                                 skip_until(')');
3311                 }
3312 end_loop:
3313                 if (token.type == ',')
3314                         next_token();
3315         }
3316 end_error:
3317         return;
3318 }
3319
3320 static declaration_t *create_error_declaration(symbol_t *symbol, storage_class_tag_t storage_class)
3321 {
3322         declaration_t *const decl    = allocate_declaration_zero();
3323         decl->source_position        = *HERE;
3324         decl->declared_storage_class = storage_class;
3325         decl->storage_class          =
3326                 storage_class != STORAGE_CLASS_NONE || scope == file_scope ?
3327                         storage_class : STORAGE_CLASS_AUTO;
3328         decl->symbol                 = symbol;
3329         decl->implicit               = true;
3330         record_declaration(decl, false);
3331         return decl;
3332 }
3333
3334 /**
3335  * Finish the construction of a struct type by calculating
3336  * its size, offsets, alignment.
3337  */
3338 static void finish_struct_type(compound_type_t *type) {
3339         if (type->declaration == NULL)
3340                 return;
3341         declaration_t *struct_decl = type->declaration;
3342         if (! struct_decl->init.complete)
3343                 return;
3344
3345         il_size_t      size           = 0;
3346         il_size_t      offset;
3347         il_alignment_t alignment      = 1;
3348         bool           need_pad       = false;
3349
3350         declaration_t *entry = struct_decl->scope.declarations;
3351         for (; entry != NULL; entry = entry->next) {
3352                 if (entry->namespc != NAMESPACE_NORMAL)
3353                         continue;
3354
3355                 type_t *m_type = skip_typeref(entry->type);
3356                 if (! is_type_valid(m_type)) {
3357                         /* simply ignore errors here */
3358                         continue;
3359                 }
3360                 il_alignment_t m_alignment = m_type->base.alignment;
3361                 if (m_alignment > alignment)
3362                         alignment = m_alignment;
3363
3364                 offset = (size + m_alignment - 1) & -m_alignment;
3365
3366                 if (offset > size)
3367                         need_pad = true;
3368                 entry->offset = offset;
3369                 size = offset + m_type->base.size;
3370         }
3371         if (type->base.alignment != 0) {
3372                 alignment = type->base.alignment;
3373         }
3374
3375         offset = (size + alignment - 1) & -alignment;
3376         if (offset > size)
3377                 need_pad = true;
3378
3379         if (warning.padded && need_pad) {
3380                 warningf(&struct_decl->source_position,
3381                         "'%#T' needs padding", type, struct_decl->symbol);
3382         }
3383         if (warning.packed && !need_pad) {
3384                 warningf(&struct_decl->source_position,
3385                         "superfluous packed attribute on '%#T'",
3386                         type, struct_decl->symbol);
3387         }
3388
3389         type->base.size      = offset;
3390         type->base.alignment = alignment;
3391 }
3392
3393 /**
3394  * Finish the construction of an union type by calculating
3395  * its size and alignment.
3396  */
3397 static void finish_union_type(compound_type_t *type) {
3398         if (type->declaration == NULL)
3399                 return;
3400         declaration_t *union_decl = type->declaration;
3401         if (! union_decl->init.complete)
3402                 return;
3403
3404         il_size_t      size      = 0;
3405         il_alignment_t alignment = 1;
3406
3407         declaration_t *entry = union_decl->scope.declarations;
3408         for (; entry != NULL; entry = entry->next) {
3409                 if (entry->namespc != NAMESPACE_NORMAL)
3410                         continue;
3411
3412                 type_t *m_type = skip_typeref(entry->type);
3413                 if (! is_type_valid(m_type))
3414                         continue;
3415
3416                 entry->offset = 0;
3417                 if (m_type->base.size > size)
3418                         size = m_type->base.size;
3419                 if (m_type->base.alignment > alignment)
3420                         alignment = m_type->base.alignment;
3421         }
3422         if (type->base.alignment != 0) {
3423                 alignment = type->base.alignment;
3424         }
3425         size = (size + alignment - 1) & -alignment;
3426         type->base.size      = size;
3427         type->base.alignment = alignment;
3428 }
3429
3430 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3431 {
3432         type_t            *type              = NULL;
3433         type_qualifiers_t  qualifiers        = TYPE_QUALIFIER_NONE;
3434         type_modifiers_t   modifiers         = TYPE_MODIFIER_NONE;
3435         unsigned           type_specifiers   = 0;
3436         bool               newtype           = false;
3437         bool               saw_error         = false;
3438         bool               old_gcc_extension = in_gcc_extension;
3439
3440         specifiers->source_position = token.source_position;
3441
3442         while (true) {
3443                 specifiers->modifiers
3444                         |= parse_attributes(&specifiers->gnu_attributes);
3445                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3446                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3447
3448                 switch (token.type) {
3449
3450                 /* storage class */
3451 #define MATCH_STORAGE_CLASS(token, class)                                  \
3452                 case token:                                                        \
3453                         if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) { \
3454                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3455                         }                                                              \
3456                         specifiers->declared_storage_class = class;                    \
3457                         next_token();                                                  \
3458                         break;
3459
3460                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3461                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3462                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3463                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3464                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3465
3466                 case T__declspec:
3467                         next_token();
3468                         expect('(');
3469                         add_anchor_token(')');
3470                         parse_microsoft_extended_decl_modifier(specifiers);
3471                         rem_anchor_token(')');
3472                         expect(')');
3473                         break;
3474
3475                 case T___thread:
3476                         switch (specifiers->declared_storage_class) {
3477                         case STORAGE_CLASS_NONE:
3478                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD;
3479                                 break;
3480
3481                         case STORAGE_CLASS_EXTERN:
3482                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_EXTERN;
3483                                 break;
3484
3485                         case STORAGE_CLASS_STATIC:
3486                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_STATIC;
3487                                 break;
3488
3489                         default:
3490                                 errorf(HERE, "multiple storage classes in declaration specifiers");
3491                                 break;
3492                         }
3493                         next_token();
3494                         break;
3495
3496                 /* type qualifiers */
3497 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3498                 case token:                                                     \
3499                         qualifiers |= qualifier;                                    \
3500                         next_token();                                               \
3501                         break
3502
3503                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3504                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3505                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3506                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3507                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3508                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3509                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3510                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3511
3512                 case T___extension__:
3513                         next_token();
3514                         in_gcc_extension = true;
3515                         break;
3516
3517                 /* type specifiers */
3518 #define MATCH_SPECIFIER(token, specifier, name)                         \
3519                 case token:                                                     \
3520                         next_token();                                               \
3521                         if (type_specifiers & specifier) {                           \
3522                                 errorf(HERE, "multiple " name " type specifiers given"); \
3523                         } else {                                                    \
3524                                 type_specifiers |= specifier;                           \
3525                         }                                                           \
3526                         break
3527
3528                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3529                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3530                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3531                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3532                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3533                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3534                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3535                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3536                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3537                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3538                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3539                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3540                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3541                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3542                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3543                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3544
3545                 case T__forceinline:
3546                         /* only in microsoft mode */
3547                         specifiers->modifiers |= DM_FORCEINLINE;
3548                         /* FALLTHROUGH */
3549
3550                 case T_inline:
3551                         next_token();
3552                         specifiers->is_inline = true;
3553                         break;
3554
3555                 case T_long:
3556                         next_token();
3557                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3558                                 errorf(HERE, "multiple type specifiers given");
3559                         } else if (type_specifiers & SPECIFIER_LONG) {
3560                                 type_specifiers |= SPECIFIER_LONG_LONG;
3561                         } else {
3562                                 type_specifiers |= SPECIFIER_LONG;
3563                         }
3564                         break;
3565
3566                 case T_struct: {
3567                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT, HERE);
3568
3569                         type->compound.declaration = parse_compound_type_specifier(true);
3570                         finish_struct_type(&type->compound);
3571                         break;
3572                 }
3573                 case T_union: {
3574                         type = allocate_type_zero(TYPE_COMPOUND_UNION, HERE);
3575                         type->compound.declaration = parse_compound_type_specifier(false);
3576                         if (type->compound.declaration->modifiers & DM_TRANSPARENT_UNION)
3577                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3578                         finish_union_type(&type->compound);
3579                         break;
3580                 }
3581                 case T_enum:
3582                         type = parse_enum_specifier();
3583                         break;
3584                 case T___typeof__:
3585                         type = parse_typeof();
3586                         break;
3587                 case T___builtin_va_list:
3588                         type = duplicate_type(type_valist);
3589                         next_token();
3590                         break;
3591
3592                 case T_IDENTIFIER: {
3593                         /* only parse identifier if we haven't found a type yet */
3594                         if (type != NULL || type_specifiers != 0) {
3595                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3596                                  * declaration, so it doesn't generate errors about expecting '(' or
3597                                  * '{' later on. */
3598                                 switch (look_ahead(1)->type) {
3599                                         STORAGE_CLASSES
3600                                         TYPE_SPECIFIERS
3601                                         case T_const:
3602                                         case T_restrict:
3603                                         case T_volatile:
3604                                         case T_inline:
3605                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3606                                         case T_IDENTIFIER:
3607                                         case '*':
3608                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3609                                                 next_token();
3610                                                 continue;
3611
3612                                         default:
3613                                                 goto finish_specifiers;
3614                                 }
3615                         }
3616
3617                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3618                         if (typedef_type == NULL) {
3619                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3620                                  * declaration, so it doesn't generate 'implicit int' followed by more
3621                                  * errors later on. */
3622                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3623                                 switch (la1_type) {
3624                                         DECLARATION_START
3625                                         case T_IDENTIFIER:
3626                                         case '*': {
3627                                                 errorf(HERE, "%K does not name a type", &token);
3628
3629                                                 declaration_t *const decl =
3630                                                         create_error_declaration(token.v.symbol, STORAGE_CLASS_TYPEDEF);
3631
3632                                                 type = allocate_type_zero(TYPE_TYPEDEF, HERE);
3633                                                 type->typedeft.declaration = decl;
3634
3635                                                 next_token();
3636                                                 saw_error = true;
3637                                                 if (la1_type == '*')
3638                                                         goto finish_specifiers;
3639                                                 continue;
3640                                         }
3641
3642                                         default:
3643                                                 goto finish_specifiers;
3644                                 }
3645                         }
3646
3647                         next_token();
3648                         type = typedef_type;
3649                         break;
3650                 }
3651
3652                 /* function specifier */
3653                 default:
3654                         goto finish_specifiers;
3655                 }
3656         }
3657
3658 finish_specifiers:
3659         in_gcc_extension = old_gcc_extension;
3660
3661         if (type == NULL || (saw_error && type_specifiers != 0)) {
3662                 atomic_type_kind_t atomic_type;
3663
3664                 /* match valid basic types */
3665                 switch(type_specifiers) {
3666                 case SPECIFIER_VOID:
3667                         atomic_type = ATOMIC_TYPE_VOID;
3668                         break;
3669                 case SPECIFIER_CHAR:
3670                         atomic_type = ATOMIC_TYPE_CHAR;
3671                         break;
3672                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3673                         atomic_type = ATOMIC_TYPE_SCHAR;
3674                         break;
3675                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3676                         atomic_type = ATOMIC_TYPE_UCHAR;
3677                         break;
3678                 case SPECIFIER_SHORT:
3679                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3680                 case SPECIFIER_SHORT | SPECIFIER_INT:
3681                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3682                         atomic_type = ATOMIC_TYPE_SHORT;
3683                         break;
3684                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3685                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3686                         atomic_type = ATOMIC_TYPE_USHORT;
3687                         break;
3688                 case SPECIFIER_INT:
3689                 case SPECIFIER_SIGNED:
3690                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3691                         atomic_type = ATOMIC_TYPE_INT;
3692                         break;
3693                 case SPECIFIER_UNSIGNED:
3694                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3695                         atomic_type = ATOMIC_TYPE_UINT;
3696                         break;
3697                 case SPECIFIER_LONG:
3698                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3699                 case SPECIFIER_LONG | SPECIFIER_INT:
3700                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3701                         atomic_type = ATOMIC_TYPE_LONG;
3702                         break;
3703                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3704                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3705                         atomic_type = ATOMIC_TYPE_ULONG;
3706                         break;
3707
3708                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3709                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3710                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3711                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3712                         | SPECIFIER_INT:
3713                         atomic_type = ATOMIC_TYPE_LONGLONG;
3714                         goto warn_about_long_long;
3715
3716                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3717                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3718                         | SPECIFIER_INT:
3719                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3720 warn_about_long_long:
3721                         if (warning.long_long) {
3722                                 warningf(&specifiers->source_position,
3723                                          "ISO C90 does not support 'long long'");
3724                         }
3725                         break;
3726
3727                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3728                         atomic_type = unsigned_int8_type_kind;
3729                         break;
3730
3731                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3732                         atomic_type = unsigned_int16_type_kind;
3733                         break;
3734
3735                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3736                         atomic_type = unsigned_int32_type_kind;
3737                         break;
3738
3739                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3740                         atomic_type = unsigned_int64_type_kind;
3741                         break;
3742
3743                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3744                         atomic_type = unsigned_int128_type_kind;
3745                         break;
3746
3747                 case SPECIFIER_INT8:
3748                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3749                         atomic_type = int8_type_kind;
3750                         break;
3751
3752                 case SPECIFIER_INT16:
3753                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3754                         atomic_type = int16_type_kind;
3755                         break;
3756
3757                 case SPECIFIER_INT32:
3758                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3759                         atomic_type = int32_type_kind;
3760                         break;
3761
3762                 case SPECIFIER_INT64:
3763                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3764                         atomic_type = int64_type_kind;
3765                         break;
3766
3767                 case SPECIFIER_INT128:
3768                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3769                         atomic_type = int128_type_kind;
3770                         break;
3771
3772                 case SPECIFIER_FLOAT:
3773                         atomic_type = ATOMIC_TYPE_FLOAT;
3774                         break;
3775                 case SPECIFIER_DOUBLE:
3776                         atomic_type = ATOMIC_TYPE_DOUBLE;
3777                         break;
3778                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3779                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3780                         break;
3781                 case SPECIFIER_BOOL:
3782                         atomic_type = ATOMIC_TYPE_BOOL;
3783                         break;
3784                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3785                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3786                         atomic_type = ATOMIC_TYPE_FLOAT;
3787                         break;
3788                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3789                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3790                         atomic_type = ATOMIC_TYPE_DOUBLE;
3791                         break;
3792                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3793                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3794                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3795                         break;
3796                 default:
3797                         /* invalid specifier combination, give an error message */
3798                         if (type_specifiers == 0) {
3799                                 if (saw_error)
3800                                         goto end_error;
3801
3802                                 if (!strict_mode) {
3803                                         if (warning.implicit_int) {
3804                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3805                                         }
3806                                         atomic_type = ATOMIC_TYPE_INT;
3807                                         break;
3808                                 } else {
3809                                         errorf(HERE, "no type specifiers given in declaration");
3810                                 }
3811                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3812                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3813                                 errorf(HERE, "signed and unsigned specifiers given");
3814                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3815                                 errorf(HERE, "only integer types can be signed or unsigned");
3816                         } else {
3817                                 errorf(HERE, "multiple datatypes in declaration");
3818                         }
3819                         goto end_error;
3820                 }
3821
3822                 if (type_specifiers & SPECIFIER_COMPLEX) {
3823                         type                = allocate_type_zero(TYPE_COMPLEX, &builtin_source_position);
3824                         type->complex.akind = atomic_type;
3825                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
3826                         type                  = allocate_type_zero(TYPE_IMAGINARY, &builtin_source_position);
3827                         type->imaginary.akind = atomic_type;
3828                 } else {
3829                         type               = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
3830                         type->atomic.akind = atomic_type;
3831                 }
3832                 newtype = true;
3833         } else if (type_specifiers != 0) {
3834                 errorf(HERE, "multiple datatypes in declaration");
3835         }
3836
3837         /* FIXME: check type qualifiers here */
3838
3839         type->base.qualifiers = qualifiers;
3840         type->base.modifiers  = modifiers;
3841
3842         type_t *result = typehash_insert(type);
3843         if (newtype && result != type) {
3844                 free_type(type);
3845         }
3846
3847         specifiers->type = result;
3848         return;
3849
3850 end_error:
3851         specifiers->type = type_error_type;
3852         return;
3853 }
3854
3855 static type_qualifiers_t parse_type_qualifiers(void)
3856 {
3857         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3858
3859         while (true) {
3860                 switch(token.type) {
3861                 /* type qualifiers */
3862                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3863                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3864                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3865                 /* microsoft extended type modifiers */
3866                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3867                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3868                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3869                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3870                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3871
3872                 default:
3873                         return qualifiers;
3874                 }
3875         }
3876 }
3877
3878 /**
3879  * Parses an K&R identifier list and return a list of declarations.
3880  *
3881  * @param last  points to the last declaration in the list
3882  * @return the list of declarations
3883  */
3884 static declaration_t *parse_identifier_list(declaration_t **last)
3885 {
3886         declaration_t *declarations     = NULL;
3887         declaration_t *last_declaration = NULL;
3888         do {
3889                 declaration_t *const declaration = allocate_declaration_zero();
3890                 declaration->type            = NULL; /* a K&R parameter list has no types, yet */
3891                 declaration->source_position = token.source_position;
3892                 declaration->symbol          = token.v.symbol;
3893                 next_token();
3894
3895                 if (last_declaration != NULL) {
3896                         last_declaration->next = declaration;
3897                 } else {
3898                         declarations = declaration;
3899                 }
3900                 last_declaration = declaration;
3901
3902                 if (token.type != ',') {
3903                         break;
3904                 }
3905                 next_token();
3906         } while (token.type == T_IDENTIFIER);
3907
3908         *last = last_declaration;
3909         return declarations;
3910 }
3911
3912 static type_t *automatic_type_conversion(type_t *orig_type);
3913
3914 static void semantic_parameter(declaration_t *declaration)
3915 {
3916         /* TODO: improve error messages */
3917         source_position_t const* const pos = &declaration->source_position;
3918
3919         switch (declaration->declared_storage_class) {
3920                 case STORAGE_CLASS_TYPEDEF:
3921                         errorf(pos, "typedef not allowed in parameter list");
3922                         break;
3923
3924                 /* Allowed storage classes */
3925                 case STORAGE_CLASS_NONE:
3926                 case STORAGE_CLASS_REGISTER:
3927                         break;
3928
3929                 default:
3930                         errorf(pos, "parameter may only have none or register storage class");
3931                         break;
3932         }
3933
3934         type_t *const orig_type = declaration->type;
3935         /* Â§6.7.5.3(7): Array as last part of a parameter type is just syntactic
3936          * sugar.  Turn it into a pointer.
3937          * Â§6.7.5.3(8): A declaration of a parameter as ``function returning type''
3938          * shall be adjusted to ``pointer to function returning type'', as in 6.3.2.1.
3939          */
3940         type_t *const type = automatic_type_conversion(orig_type);
3941         declaration->type = type;
3942
3943         if (is_type_incomplete(skip_typeref(type))) {
3944                 errorf(pos, "parameter '%#T' is of incomplete type",
3945                        orig_type, declaration->symbol);
3946         }
3947 }
3948
3949 static declaration_t *parse_parameter(void)
3950 {
3951         declaration_specifiers_t specifiers;
3952         memset(&specifiers, 0, sizeof(specifiers));
3953
3954         parse_declaration_specifiers(&specifiers);
3955
3956         declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/true);
3957
3958         return declaration;
3959 }
3960
3961 /**
3962  * Parses a function type parameter list and return a list of declarations.
3963  *
3964  * @param last  point to the last element of the list
3965  * @return the parameter list
3966  */
3967 static declaration_t *parse_parameters(function_type_t *type, declaration_t **last)
3968 {
3969         declaration_t *declarations = NULL;
3970
3971         eat('(');
3972         add_anchor_token(')');
3973         int saved_comma_state = save_and_reset_anchor_state(',');
3974
3975         if (token.type == T_IDENTIFIER &&
3976             !is_typedef_symbol(token.v.symbol)) {
3977                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
3978                 if (la1_type == ',' || la1_type == ')') {
3979                         type->kr_style_parameters = true;
3980                         declarations = parse_identifier_list(last);
3981                         goto parameters_finished;
3982                 }
3983         }
3984
3985         if (token.type == ')') {
3986                 type->unspecified_parameters = 1;
3987                 goto parameters_finished;
3988         }
3989
3990         declaration_t        *declaration;
3991         declaration_t        *last_declaration = NULL;
3992         function_parameter_t *parameter;
3993         function_parameter_t *last_parameter = NULL;
3994
3995         while (true) {
3996                 switch(token.type) {
3997                 case T_DOTDOTDOT:
3998                         next_token();
3999                         type->variadic = 1;
4000                         goto parameters_finished;
4001
4002                 case T_IDENTIFIER:
4003                 case T___extension__:
4004                 DECLARATION_START
4005                         declaration = parse_parameter();
4006
4007                         /* func(void) is not a parameter */
4008                         if (last_parameter == NULL
4009                                         && token.type == ')'
4010                                         && declaration->symbol == NULL
4011                                         && skip_typeref(declaration->type) == type_void) {
4012                                 goto parameters_finished;
4013                         }
4014                         semantic_parameter(declaration);
4015
4016                         parameter       = obstack_alloc(type_obst, sizeof(parameter[0]));
4017                         memset(parameter, 0, sizeof(parameter[0]));
4018                         parameter->type = declaration->type;
4019
4020                         if (last_parameter != NULL) {
4021                                 last_declaration->next = declaration;
4022                                 last_parameter->next   = parameter;
4023                         } else {
4024                                 type->parameters = parameter;
4025                                 declarations     = declaration;
4026                         }
4027                         last_parameter   = parameter;
4028                         last_declaration = declaration;
4029                         break;
4030
4031                 default:
4032                         goto parameters_finished;
4033                 }
4034                 if (token.type != ',') {
4035                         goto parameters_finished;
4036                 }
4037                 next_token();
4038         }
4039
4040
4041 parameters_finished:
4042         rem_anchor_token(')');
4043         expect(')');
4044
4045         restore_anchor_state(',', saved_comma_state);
4046         *last = last_declaration;
4047         return declarations;
4048
4049 end_error:
4050         restore_anchor_state(',', saved_comma_state);
4051         *last = NULL;
4052         return NULL;
4053 }
4054
4055 typedef enum construct_type_kind_t {
4056         CONSTRUCT_INVALID,
4057         CONSTRUCT_POINTER,
4058         CONSTRUCT_FUNCTION,
4059         CONSTRUCT_ARRAY
4060 } construct_type_kind_t;
4061
4062 typedef struct construct_type_t construct_type_t;
4063 struct construct_type_t {
4064         construct_type_kind_t  kind;
4065         construct_type_t      *next;
4066 };
4067
4068 typedef struct parsed_pointer_t parsed_pointer_t;
4069 struct parsed_pointer_t {
4070         construct_type_t  construct_type;
4071         type_qualifiers_t type_qualifiers;
4072 };
4073
4074 typedef struct construct_function_type_t construct_function_type_t;
4075 struct construct_function_type_t {
4076         construct_type_t  construct_type;
4077         type_t           *function_type;
4078 };
4079
4080 typedef struct parsed_array_t parsed_array_t;
4081 struct parsed_array_t {
4082         construct_type_t  construct_type;
4083         type_qualifiers_t type_qualifiers;
4084         bool              is_static;
4085         bool              is_variable;
4086         expression_t     *size;
4087 };
4088
4089 typedef struct construct_base_type_t construct_base_type_t;
4090 struct construct_base_type_t {
4091         construct_type_t  construct_type;
4092         type_t           *type;
4093 };
4094
4095 static construct_type_t *parse_pointer_declarator(void)
4096 {
4097         eat('*');
4098
4099         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
4100         memset(pointer, 0, sizeof(pointer[0]));
4101         pointer->construct_type.kind = CONSTRUCT_POINTER;
4102         pointer->type_qualifiers     = parse_type_qualifiers();
4103
4104         return (construct_type_t*) pointer;
4105 }
4106
4107 static construct_type_t *parse_array_declarator(void)
4108 {
4109         eat('[');
4110         add_anchor_token(']');
4111
4112         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
4113         memset(array, 0, sizeof(array[0]));
4114         array->construct_type.kind = CONSTRUCT_ARRAY;
4115
4116         if (token.type == T_static) {
4117                 array->is_static = true;
4118                 next_token();
4119         }
4120
4121         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
4122         if (type_qualifiers != 0) {
4123                 if (token.type == T_static) {
4124                         array->is_static = true;
4125                         next_token();
4126                 }
4127         }
4128         array->type_qualifiers = type_qualifiers;
4129
4130         if (token.type == '*' && look_ahead(1)->type == ']') {
4131                 array->is_variable = true;
4132                 next_token();
4133         } else if (token.type != ']') {
4134                 array->size = parse_assignment_expression();
4135         }
4136
4137         rem_anchor_token(']');
4138         expect(']');
4139
4140 end_error:
4141         return (construct_type_t*) array;
4142 }
4143
4144 static construct_type_t *parse_function_declarator(declaration_t *declaration)
4145 {
4146         type_t *type;
4147         if (declaration != NULL) {
4148                 type = allocate_type_zero(TYPE_FUNCTION, &declaration->source_position);
4149
4150                 unsigned mask = declaration->modifiers & (DM_CDECL|DM_STDCALL|DM_FASTCALL|DM_THISCALL);
4151
4152                 if (mask & (mask-1)) {
4153                         const char *first = NULL, *second = NULL;
4154
4155                         /* more than one calling convention set */
4156                         if (declaration->modifiers & DM_CDECL) {
4157                                 if (first == NULL)       first = "cdecl";
4158                                 else if (second == NULL) second = "cdecl";
4159                         }
4160                         if (declaration->modifiers & DM_STDCALL) {
4161                                 if (first == NULL)       first = "stdcall";
4162                                 else if (second == NULL) second = "stdcall";
4163                         }
4164                         if (declaration->modifiers & DM_FASTCALL) {
4165                                 if (first == NULL)       first = "fastcall";
4166                                 else if (second == NULL) second = "fastcall";
4167                         }
4168                         if (declaration->modifiers & DM_THISCALL) {
4169                                 if (first == NULL)       first = "thiscall";
4170                                 else if (second == NULL) second = "thiscall";
4171                         }
4172                         errorf(&declaration->source_position, "%s and %s attributes are not compatible", first, second);
4173                 }
4174
4175                 if (declaration->modifiers & DM_CDECL)
4176                         type->function.calling_convention = CC_CDECL;
4177                 else if (declaration->modifiers & DM_STDCALL)
4178                         type->function.calling_convention = CC_STDCALL;
4179                 else if (declaration->modifiers & DM_FASTCALL)
4180                         type->function.calling_convention = CC_FASTCALL;
4181                 else if (declaration->modifiers & DM_THISCALL)
4182                         type->function.calling_convention = CC_THISCALL;
4183         } else {
4184                 type = allocate_type_zero(TYPE_FUNCTION, HERE);
4185         }
4186
4187         declaration_t *last;
4188         declaration_t *parameters = parse_parameters(&type->function, &last);
4189         if (declaration != NULL) {
4190                 declaration->scope.declarations     = parameters;
4191                 declaration->scope.last_declaration = last;
4192                 declaration->scope.is_parameter     = true;
4193         }
4194
4195         construct_function_type_t *construct_function_type =
4196                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
4197         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
4198         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
4199         construct_function_type->function_type       = type;
4200
4201         return &construct_function_type->construct_type;
4202 }
4203
4204 static void fix_declaration_type(declaration_t *declaration)
4205 {
4206         decl_modifiers_t declaration_modifiers = declaration->modifiers;
4207         type_modifiers_t type_modifiers        = declaration->type->base.modifiers;
4208
4209         if (declaration_modifiers & DM_TRANSPARENT_UNION)
4210                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
4211
4212         if (declaration->type->base.modifiers == type_modifiers)
4213                 return;
4214
4215         type_t *copy = duplicate_type(declaration->type);
4216         copy->base.modifiers = type_modifiers;
4217
4218         type_t *result = typehash_insert(copy);
4219         if (result != copy) {
4220                 obstack_free(type_obst, copy);
4221         }
4222
4223         declaration->type = result;
4224 }
4225
4226 static construct_type_t *parse_inner_declarator(declaration_t *declaration,
4227                 bool may_be_abstract)
4228 {
4229         /* construct a single linked list of construct_type_t's which describe
4230          * how to construct the final declarator type */
4231         construct_type_t *first = NULL;
4232         construct_type_t *last  = NULL;
4233         gnu_attribute_t  *attributes = NULL;
4234
4235         decl_modifiers_t modifiers = parse_attributes(&attributes);
4236
4237         /* pointers */
4238         while (token.type == '*') {
4239                 construct_type_t *type = parse_pointer_declarator();
4240
4241                 if (last == NULL) {
4242                         first = type;
4243                         last  = type;
4244                 } else {
4245                         last->next = type;
4246                         last       = type;
4247                 }
4248
4249                 /* TODO: find out if this is correct */
4250                 modifiers |= parse_attributes(&attributes);
4251         }
4252
4253         if (declaration != NULL)
4254                 declaration->modifiers |= modifiers;
4255
4256         construct_type_t *inner_types = NULL;
4257
4258         switch(token.type) {
4259         case T_IDENTIFIER:
4260                 if (declaration == NULL) {
4261                         errorf(HERE, "no identifier expected in typename");
4262                 } else {
4263                         declaration->symbol          = token.v.symbol;
4264                         declaration->source_position = token.source_position;
4265                 }
4266                 next_token();
4267                 break;
4268         case '(':
4269                 next_token();
4270                 add_anchor_token(')');
4271                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
4272                 if (inner_types != NULL) {
4273                         /* All later declarators only modify the return type, not declaration */
4274                         declaration = NULL;
4275                 }
4276                 rem_anchor_token(')');
4277                 expect(')');
4278                 break;
4279         default:
4280                 if (may_be_abstract)
4281                         break;
4282                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4283                 eat_until_anchor();
4284                 return NULL;
4285         }
4286
4287         construct_type_t *p = last;
4288
4289         while(true) {
4290                 construct_type_t *type;
4291                 switch(token.type) {
4292                 case '(':
4293                         type = parse_function_declarator(declaration);
4294                         break;
4295                 case '[':
4296                         type = parse_array_declarator();
4297                         break;
4298                 default:
4299                         goto declarator_finished;
4300                 }
4301
4302                 /* insert in the middle of the list (behind p) */
4303                 if (p != NULL) {
4304                         type->next = p->next;
4305                         p->next    = type;
4306                 } else {
4307                         type->next = first;
4308                         first      = type;
4309                 }
4310                 if (last == p) {
4311                         last = type;
4312                 }
4313         }
4314
4315 declarator_finished:
4316         /* append inner_types at the end of the list, we don't to set last anymore
4317          * as it's not needed anymore */
4318         if (last == NULL) {
4319                 assert(first == NULL);
4320                 first = inner_types;
4321         } else {
4322                 last->next = inner_types;
4323         }
4324
4325         return first;
4326 end_error:
4327         return NULL;
4328 }
4329
4330 static void parse_declaration_attributes(declaration_t *declaration)
4331 {
4332         gnu_attribute_t  *attributes = NULL;
4333         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4334
4335         if (declaration == NULL)
4336                 return;
4337
4338         declaration->modifiers |= modifiers;
4339         /* check if we have these stupid mode attributes... */
4340         type_t *old_type = declaration->type;
4341         if (old_type == NULL)
4342                 return;
4343
4344         gnu_attribute_t *attribute = attributes;
4345         for ( ; attribute != NULL; attribute = attribute->next) {
4346                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
4347                         continue;
4348
4349                 atomic_type_kind_t  akind = attribute->u.akind;
4350                 if (!is_type_signed(old_type)) {
4351                         switch(akind) {
4352                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
4353                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
4354                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
4355                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
4356                         default:
4357                                 panic("invalid akind in mode attribute");
4358                         }
4359                 }
4360                 declaration->type
4361                         = make_atomic_type(akind, old_type->base.qualifiers);
4362         }
4363 }
4364
4365 static type_t *construct_declarator_type(construct_type_t *construct_list,
4366                                          type_t *type)
4367 {
4368         construct_type_t *iter = construct_list;
4369         for( ; iter != NULL; iter = iter->next) {
4370                 switch(iter->kind) {
4371                 case CONSTRUCT_INVALID:
4372                         internal_errorf(HERE, "invalid type construction found");
4373                 case CONSTRUCT_FUNCTION: {
4374                         construct_function_type_t *construct_function_type
4375                                 = (construct_function_type_t*) iter;
4376
4377                         type_t *function_type = construct_function_type->function_type;
4378
4379                         function_type->function.return_type = type;
4380
4381                         type_t *skipped_return_type = skip_typeref(type);
4382                         /* Â§6.7.5.3(1) */
4383                         if (is_type_function(skipped_return_type)) {
4384                                 errorf(HERE, "function returning function is not allowed");
4385                         } else if (is_type_array(skipped_return_type)) {
4386                                 errorf(HERE, "function returning array is not allowed");
4387                         } else {
4388                                 if (skipped_return_type->base.qualifiers != 0) {
4389                                         warningf(HERE,
4390                                                 "type qualifiers in return type of function type are meaningless");
4391                                 }
4392                         }
4393
4394                         type = function_type;
4395                         break;
4396                 }
4397
4398                 case CONSTRUCT_POINTER: {
4399                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4400                         type_t           *pointer_type   = allocate_type_zero(TYPE_POINTER, &null_position);
4401                         pointer_type->pointer.points_to  = type;
4402                         pointer_type->base.qualifiers    = parsed_pointer->type_qualifiers;
4403
4404                         type = pointer_type;
4405                         break;
4406                 }
4407
4408                 case CONSTRUCT_ARRAY: {
4409                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4410                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY, &null_position);
4411
4412                         expression_t *size_expression = parsed_array->size;
4413                         if (size_expression != NULL) {
4414                                 size_expression
4415                                         = create_implicit_cast(size_expression, type_size_t);
4416                         }
4417
4418                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4419                         array_type->array.element_type    = type;
4420                         array_type->array.is_static       = parsed_array->is_static;
4421                         array_type->array.is_variable     = parsed_array->is_variable;
4422                         array_type->array.size_expression = size_expression;
4423
4424                         if (size_expression != NULL) {
4425                                 if (is_constant_expression(size_expression)) {
4426                                         array_type->array.size_constant = true;
4427                                         array_type->array.size
4428                                                 = fold_constant(size_expression);
4429                                 } else {
4430                                         array_type->array.is_vla = true;
4431                                 }
4432                         }
4433
4434                         type_t *skipped_type = skip_typeref(type);
4435                         /* Â§6.7.5.2(1) */
4436                         if (is_type_incomplete(skipped_type)) {
4437                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
4438                         } else if (is_type_function(skipped_type)) {
4439                                 errorf(HERE, "array of functions is not allowed");
4440                         }
4441                         type = array_type;
4442                         break;
4443                 }
4444                 }
4445
4446                 type_t *hashed_type = typehash_insert(type);
4447                 if (hashed_type != type) {
4448                         /* the function type was constructed earlier freeing it here will
4449                          * destroy other types... */
4450                         if (iter->kind != CONSTRUCT_FUNCTION) {
4451                                 free_type(type);
4452                         }
4453                         type = hashed_type;
4454                 }
4455         }
4456
4457         return type;
4458 }
4459
4460 static declaration_t *parse_declarator(
4461                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
4462 {
4463         declaration_t *const declaration    = allocate_declaration_zero();
4464         declaration->source_position        = specifiers->source_position;
4465         declaration->declared_storage_class = specifiers->declared_storage_class;
4466         declaration->modifiers              = specifiers->modifiers;
4467         declaration->deprecated_string      = specifiers->deprecated_string;
4468         declaration->get_property_sym       = specifiers->get_property_sym;
4469         declaration->put_property_sym       = specifiers->put_property_sym;
4470         declaration->is_inline              = specifiers->is_inline;
4471
4472         declaration->storage_class          = specifiers->declared_storage_class;
4473         if (declaration->storage_class == STORAGE_CLASS_NONE &&
4474             scope != file_scope) {
4475                 declaration->storage_class = STORAGE_CLASS_AUTO;
4476         }
4477
4478         if (specifiers->alignment != 0) {
4479                 /* TODO: add checks here */
4480                 declaration->alignment = specifiers->alignment;
4481         }
4482
4483         construct_type_t *construct_type
4484                 = parse_inner_declarator(declaration, may_be_abstract);
4485         type_t *const type = specifiers->type;
4486         declaration->type = construct_declarator_type(construct_type, type);
4487
4488         parse_declaration_attributes(declaration);
4489
4490         fix_declaration_type(declaration);
4491
4492         if (construct_type != NULL) {
4493                 obstack_free(&temp_obst, construct_type);
4494         }
4495
4496         return declaration;
4497 }
4498
4499 static type_t *parse_abstract_declarator(type_t *base_type)
4500 {
4501         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4502
4503         type_t *result = construct_declarator_type(construct_type, base_type);
4504         if (construct_type != NULL) {
4505                 obstack_free(&temp_obst, construct_type);
4506         }
4507
4508         return result;
4509 }
4510
4511 static declaration_t *append_declaration(declaration_t* const declaration)
4512 {
4513         if (last_declaration != NULL) {
4514                 last_declaration->next = declaration;
4515         } else {
4516                 scope->declarations = declaration;
4517         }
4518         last_declaration = declaration;
4519         return declaration;
4520 }
4521
4522 /**
4523  * Check if the declaration of main is suspicious.  main should be a
4524  * function with external linkage, returning int, taking either zero
4525  * arguments, two, or three arguments of appropriate types, ie.
4526  *
4527  * int main([ int argc, char **argv [, char **env ] ]).
4528  *
4529  * @param decl    the declaration to check
4530  * @param type    the function type of the declaration
4531  */
4532 static void check_type_of_main(const declaration_t *const decl, const function_type_t *const func_type)
4533 {
4534         if (decl->storage_class == STORAGE_CLASS_STATIC) {
4535                 warningf(&decl->source_position,
4536                          "'main' is normally a non-static function");
4537         }
4538         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4539                 warningf(&decl->source_position,
4540                          "return type of 'main' should be 'int', but is '%T'",
4541                          func_type->return_type);
4542         }
4543         const function_parameter_t *parm = func_type->parameters;
4544         if (parm != NULL) {
4545                 type_t *const first_type = parm->type;
4546                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4547                         warningf(&decl->source_position,
4548                                  "first argument of 'main' should be 'int', but is '%T'", first_type);
4549                 }
4550                 parm = parm->next;
4551                 if (parm != NULL) {
4552                         type_t *const second_type = parm->type;
4553                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4554                                 warningf(&decl->source_position,
4555                                          "second argument of 'main' should be 'char**', but is '%T'", second_type);
4556                         }
4557                         parm = parm->next;
4558                         if (parm != NULL) {
4559                                 type_t *const third_type = parm->type;
4560                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4561                                         warningf(&decl->source_position,
4562                                                  "third argument of 'main' should be 'char**', but is '%T'", third_type);
4563                                 }
4564                                 parm = parm->next;
4565                                 if (parm != NULL)
4566                                         goto warn_arg_count;
4567                         }
4568                 } else {
4569 warn_arg_count:
4570                         warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
4571                 }
4572         }
4573 }
4574
4575 /**
4576  * Check if a symbol is the equal to "main".
4577  */
4578 static bool is_sym_main(const symbol_t *const sym)
4579 {
4580         return strcmp(sym->string, "main") == 0;
4581 }
4582
4583 static declaration_t *record_declaration(
4584         declaration_t *const declaration,
4585         const bool is_definition)
4586 {
4587         const symbol_t *const symbol  = declaration->symbol;
4588         const namespace_t     namespc = (namespace_t)declaration->namespc;
4589
4590         assert(symbol != NULL);
4591         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4592
4593         type_t *const orig_type = declaration->type;
4594         type_t *const type      = skip_typeref(orig_type);
4595         if (is_type_function(type) &&
4596                         type->function.unspecified_parameters &&
4597                         warning.strict_prototypes &&
4598                         previous_declaration == NULL) {
4599                 warningf(&declaration->source_position,
4600                          "function declaration '%#T' is not a prototype",
4601                          orig_type, symbol);
4602         }
4603
4604         if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
4605                 check_type_of_main(declaration, &type->function);
4606         }
4607
4608         if (warning.nested_externs                             &&
4609             declaration->storage_class == STORAGE_CLASS_EXTERN &&
4610             scope                      != file_scope) {
4611                 warningf(&declaration->source_position,
4612                          "nested extern declaration of '%#T'", declaration->type, symbol);
4613         }
4614
4615         assert(declaration != previous_declaration);
4616         if (previous_declaration != NULL &&
4617             previous_declaration->parent_scope->is_parameter &&
4618             scope->depth == previous_declaration->parent_scope->depth + 1) {
4619                 errorf(&declaration->source_position,
4620                         "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
4621                         orig_type, symbol, previous_declaration->type, symbol,
4622                         &previous_declaration->source_position);
4623                 goto finish;
4624         }
4625         if (previous_declaration != NULL &&
4626             previous_declaration->parent_scope == scope) {
4627                 /* can happen for K&R style declarations */
4628                 if (previous_declaration->type == NULL) {
4629                         previous_declaration->type = declaration->type;
4630                 }
4631
4632                 const type_t *prev_type = skip_typeref(previous_declaration->type);
4633                 if (!types_compatible(type, prev_type)) {
4634                         errorf(&declaration->source_position,
4635                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
4636                                    orig_type, symbol, previous_declaration->type, symbol,
4637                                    &previous_declaration->source_position);
4638                 } else {
4639                         unsigned old_storage_class = previous_declaration->storage_class;
4640                         if (old_storage_class == STORAGE_CLASS_ENUM_ENTRY) {
4641                                 errorf(&declaration->source_position,
4642                                            "redeclaration of enum entry '%Y' (declared %P)",
4643                                            symbol, &previous_declaration->source_position);
4644                                 return previous_declaration;
4645                         }
4646
4647                         if (warning.redundant_decls                                     &&
4648                             is_definition                                               &&
4649                             previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
4650                             !(previous_declaration->modifiers & DM_USED)                &&
4651                             !previous_declaration->used) {
4652                                 warningf(&previous_declaration->source_position,
4653                                          "unnecessary static forward declaration for '%#T'",
4654                                          previous_declaration->type, symbol);
4655                         }
4656
4657                         unsigned new_storage_class = declaration->storage_class;
4658
4659                         if (is_type_incomplete(prev_type)) {
4660                                 previous_declaration->type = type;
4661                                 prev_type                  = type;
4662                         }
4663
4664                         /* pretend no storage class means extern for function
4665                          * declarations (except if the previous declaration is neither
4666                          * none nor extern) */
4667                         if (is_type_function(type)) {
4668                                 if (prev_type->function.unspecified_parameters) {
4669                                         previous_declaration->type = type;
4670                                         prev_type                  = type;
4671                                 }
4672
4673                                 switch (old_storage_class) {
4674                                 case STORAGE_CLASS_NONE:
4675                                         old_storage_class = STORAGE_CLASS_EXTERN;
4676                                         /* FALLTHROUGH */
4677
4678                                 case STORAGE_CLASS_EXTERN:
4679                                         if (is_definition) {
4680                                                 if (warning.missing_prototypes &&
4681                                                     prev_type->function.unspecified_parameters &&
4682                                                     !is_sym_main(symbol)) {
4683                                                         warningf(&declaration->source_position,
4684                                                                          "no previous prototype for '%#T'",
4685                                                                          orig_type, symbol);
4686                                                 }
4687                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4688                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4689                                         }
4690                                         break;
4691
4692                                 default:
4693                                         break;
4694                                 }
4695                         }
4696
4697                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
4698                                         new_storage_class == STORAGE_CLASS_EXTERN) {
4699 warn_redundant_declaration:
4700                                 if (!is_definition           &&
4701                                     warning.redundant_decls  &&
4702                                     is_type_valid(prev_type) &&
4703                                     strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
4704                                         warningf(&declaration->source_position,
4705                                                  "redundant declaration for '%Y' (declared %P)",
4706                                                  symbol, &previous_declaration->source_position);
4707                                 }
4708                         } else if (current_function == NULL) {
4709                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
4710                                     new_storage_class == STORAGE_CLASS_STATIC) {
4711                                         errorf(&declaration->source_position,
4712                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
4713                                                symbol, &previous_declaration->source_position);
4714                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4715                                         previous_declaration->storage_class          = STORAGE_CLASS_NONE;
4716                                         previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
4717                                 } else {
4718                                         goto warn_redundant_declaration;
4719                                 }
4720                         } else if (is_type_valid(prev_type)) {
4721                                 if (old_storage_class == new_storage_class) {
4722                                         errorf(&declaration->source_position,
4723                                                "redeclaration of '%Y' (declared %P)",
4724                                                symbol, &previous_declaration->source_position);
4725                                 } else {
4726                                         errorf(&declaration->source_position,
4727                                                "redeclaration of '%Y' with different linkage (declared %P)",
4728                                                symbol, &previous_declaration->source_position);
4729                                 }
4730                         }
4731                 }
4732
4733                 previous_declaration->modifiers |= declaration->modifiers;
4734                 previous_declaration->is_inline |= declaration->is_inline;
4735                 return previous_declaration;
4736         } else if (is_type_function(type)) {
4737                 if (is_definition &&
4738                     declaration->storage_class != STORAGE_CLASS_STATIC) {
4739                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4740                                 warningf(&declaration->source_position,
4741                                          "no previous prototype for '%#T'", orig_type, symbol);
4742                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4743                                 warningf(&declaration->source_position,
4744                                          "no previous declaration for '%#T'", orig_type,
4745                                          symbol);
4746                         }
4747                 }
4748         } else {
4749                 if (warning.missing_declarations &&
4750                     scope == file_scope && (
4751                       declaration->storage_class == STORAGE_CLASS_NONE ||
4752                       declaration->storage_class == STORAGE_CLASS_THREAD
4753                     )) {
4754                         warningf(&declaration->source_position,
4755                                  "no previous declaration for '%#T'", orig_type, symbol);
4756                 }
4757         }
4758 finish:
4759         assert(declaration->parent_scope == NULL);
4760         assert(scope != NULL);
4761
4762         declaration->parent_scope = scope;
4763
4764         environment_push(declaration);
4765         return append_declaration(declaration);
4766 }
4767
4768 static void parser_error_multiple_definition(declaration_t *declaration,
4769                 const source_position_t *source_position)
4770 {
4771         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
4772                declaration->symbol, &declaration->source_position);
4773 }
4774
4775 static bool is_declaration_specifier(const token_t *token,
4776                                      bool only_specifiers_qualifiers)
4777 {
4778         switch (token->type) {
4779                 TYPE_SPECIFIERS
4780                 TYPE_QUALIFIERS
4781                         return true;
4782                 case T_IDENTIFIER:
4783                         return is_typedef_symbol(token->v.symbol);
4784
4785                 case T___extension__:
4786                 STORAGE_CLASSES
4787                         return !only_specifiers_qualifiers;
4788
4789                 default:
4790                         return false;
4791         }
4792 }
4793
4794 static void parse_init_declarator_rest(declaration_t *declaration)
4795 {
4796         eat('=');
4797
4798         type_t *orig_type = declaration->type;
4799         type_t *type      = skip_typeref(orig_type);
4800
4801         if (declaration->init.initializer != NULL) {
4802                 parser_error_multiple_definition(declaration, HERE);
4803         }
4804
4805         bool must_be_constant = false;
4806         if (declaration->storage_class == STORAGE_CLASS_STATIC        ||
4807             declaration->storage_class == STORAGE_CLASS_THREAD_STATIC ||
4808             declaration->parent_scope  == file_scope) {
4809                 must_be_constant = true;
4810         }
4811
4812         if (is_type_function(type)) {
4813                 errorf(&declaration->source_position,
4814                        "function '%#T' is initialized like a variable",
4815                        orig_type, declaration->symbol);
4816                 orig_type = type_error_type;
4817         }
4818
4819         parse_initializer_env_t env;
4820         env.type             = orig_type;
4821         env.must_be_constant = must_be_constant;
4822         env.declaration      = current_init_decl = declaration;
4823
4824         initializer_t *initializer = parse_initializer(&env);
4825         current_init_decl = NULL;
4826
4827         if (!is_type_function(type)) {
4828                 /* Â§ 6.7.5 (22)  array initializers for arrays with unknown size determine
4829                  * the array type size */
4830                 declaration->type             = env.type;
4831                 declaration->init.initializer = initializer;
4832         }
4833 }
4834
4835 /* parse rest of a declaration without any declarator */
4836 static void parse_anonymous_declaration_rest(
4837                 const declaration_specifiers_t *specifiers)
4838 {
4839         eat(';');
4840
4841         if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) {
4842                 warningf(&specifiers->source_position,
4843                          "useless storage class in empty declaration");
4844         }
4845
4846         type_t *type = specifiers->type;
4847         switch (type->kind) {
4848                 case TYPE_COMPOUND_STRUCT:
4849                 case TYPE_COMPOUND_UNION: {
4850                         if (type->compound.declaration->symbol == NULL) {
4851                                 warningf(&specifiers->source_position,
4852                                          "unnamed struct/union that defines no instances");
4853                         }
4854                         break;
4855                 }
4856
4857                 case TYPE_ENUM:
4858                         break;
4859
4860                 default:
4861                         warningf(&specifiers->source_position, "empty declaration");
4862                         break;
4863         }
4864
4865 #ifdef RECORD_EMPTY_DECLARATIONS
4866         declaration_t *const declaration    = allocate_declaration_zero();
4867         declaration->type                   = specifiers->type;
4868         declaration->declared_storage_class = specifiers->declared_storage_class;
4869         declaration->source_position        = specifiers->source_position;
4870         declaration->modifiers              = specifiers->modifiers;
4871         declaration->storage_class          = STORAGE_CLASS_NONE;
4872
4873         append_declaration(declaration);
4874 #endif
4875 }
4876
4877 static void parse_declaration_rest(declaration_t *ndeclaration,
4878                 const declaration_specifiers_t *specifiers,
4879                 parsed_declaration_func finished_declaration)
4880 {
4881         add_anchor_token(';');
4882         add_anchor_token(',');
4883         while(true) {
4884                 declaration_t *declaration =
4885                         finished_declaration(ndeclaration, token.type == '=');
4886
4887                 type_t *orig_type = declaration->type;
4888                 type_t *type      = skip_typeref(orig_type);
4889
4890                 if (type->kind != TYPE_FUNCTION &&
4891                     declaration->is_inline &&
4892                     is_type_valid(type)) {
4893                         warningf(&declaration->source_position,
4894                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
4895                 }
4896
4897                 if (token.type == '=') {
4898                         parse_init_declarator_rest(declaration);
4899                 }
4900
4901                 if (token.type != ',')
4902                         break;
4903                 eat(',');
4904
4905                 add_anchor_token('=');
4906                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
4907                 rem_anchor_token('=');
4908         }
4909         expect(';');
4910
4911 end_error:
4912         rem_anchor_token(';');
4913         rem_anchor_token(',');
4914 }
4915
4916 static declaration_t *finished_kr_declaration(declaration_t *declaration, bool is_definition)
4917 {
4918         symbol_t *symbol  = declaration->symbol;
4919         if (symbol == NULL) {
4920                 errorf(HERE, "anonymous declaration not valid as function parameter");
4921                 return declaration;
4922         }
4923         namespace_t namespc = (namespace_t) declaration->namespc;
4924         if (namespc != NAMESPACE_NORMAL) {
4925                 return record_declaration(declaration, false);
4926         }
4927
4928         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4929         if (previous_declaration == NULL ||
4930                         previous_declaration->parent_scope != scope) {
4931                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4932                        symbol);
4933                 return declaration;
4934         }
4935
4936         if (is_definition) {
4937                 errorf(HERE, "parameter %Y is initialised", declaration->symbol);
4938         }
4939
4940         if (previous_declaration->type == NULL) {
4941                 previous_declaration->type          = declaration->type;
4942                 previous_declaration->declared_storage_class = declaration->declared_storage_class;
4943                 previous_declaration->storage_class = declaration->storage_class;
4944                 previous_declaration->parent_scope  = scope;
4945                 return previous_declaration;
4946         } else {
4947                 return record_declaration(declaration, false);
4948         }
4949 }
4950
4951 static void parse_declaration(parsed_declaration_func finished_declaration)
4952 {
4953         declaration_specifiers_t specifiers;
4954         memset(&specifiers, 0, sizeof(specifiers));
4955
4956         add_anchor_token(';');
4957         parse_declaration_specifiers(&specifiers);
4958         rem_anchor_token(';');
4959
4960         if (token.type == ';') {
4961                 parse_anonymous_declaration_rest(&specifiers);
4962         } else {
4963                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
4964                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
4965         }
4966 }
4967
4968 static type_t *get_default_promoted_type(type_t *orig_type)
4969 {
4970         type_t *result = orig_type;
4971
4972         type_t *type = skip_typeref(orig_type);
4973         if (is_type_integer(type)) {
4974                 result = promote_integer(type);
4975         } else if (type == type_float) {
4976                 result = type_double;
4977         }
4978
4979         return result;
4980 }
4981
4982 static void parse_kr_declaration_list(declaration_t *declaration)
4983 {
4984         type_t *type = skip_typeref(declaration->type);
4985         if (!is_type_function(type))
4986                 return;
4987
4988         if (!type->function.kr_style_parameters)
4989                 return;
4990
4991         add_anchor_token('{');
4992
4993         /* push function parameters */
4994         size_t const top = environment_top();
4995         scope_push(&declaration->scope);
4996
4997         declaration_t *parameter = declaration->scope.declarations;
4998         for ( ; parameter != NULL; parameter = parameter->next) {
4999                 assert(parameter->parent_scope == NULL);
5000                 parameter->parent_scope = scope;
5001                 environment_push(parameter);
5002         }
5003
5004         /* parse declaration list */
5005         while (is_declaration_specifier(&token, false)) {
5006                 parse_declaration(finished_kr_declaration);
5007         }
5008
5009         /* pop function parameters */
5010         assert(scope == &declaration->scope);
5011         scope_pop();
5012         environment_pop_to(top);
5013
5014         /* update function type */
5015         type_t *new_type = duplicate_type(type);
5016
5017         function_parameter_t *parameters     = NULL;
5018         function_parameter_t *last_parameter = NULL;
5019
5020         declaration_t *parameter_declaration = declaration->scope.declarations;
5021         for( ; parameter_declaration != NULL;
5022                         parameter_declaration = parameter_declaration->next) {
5023                 type_t *parameter_type = parameter_declaration->type;
5024                 if (parameter_type == NULL) {
5025                         if (strict_mode) {
5026                                 errorf(HERE, "no type specified for function parameter '%Y'",
5027                                        parameter_declaration->symbol);
5028                         } else {
5029                                 if (warning.implicit_int) {
5030                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
5031                                                 parameter_declaration->symbol);
5032                                 }
5033                                 parameter_type              = type_int;
5034                                 parameter_declaration->type = parameter_type;
5035                         }
5036                 }
5037
5038                 semantic_parameter(parameter_declaration);
5039                 parameter_type = parameter_declaration->type;
5040
5041                 /*
5042                  * we need the default promoted types for the function type
5043                  */
5044                 parameter_type = get_default_promoted_type(parameter_type);
5045
5046                 function_parameter_t *function_parameter
5047                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
5048                 memset(function_parameter, 0, sizeof(function_parameter[0]));
5049
5050                 function_parameter->type = parameter_type;
5051                 if (last_parameter != NULL) {
5052                         last_parameter->next = function_parameter;
5053                 } else {
5054                         parameters = function_parameter;
5055                 }
5056                 last_parameter = function_parameter;
5057         }
5058
5059         /* Â§ 6.9.1.7: A K&R style parameter list does NOT act as a function
5060          * prototype */
5061         new_type->function.parameters             = parameters;
5062         new_type->function.unspecified_parameters = true;
5063
5064         type = typehash_insert(new_type);
5065         if (type != new_type) {
5066                 obstack_free(type_obst, new_type);
5067         }
5068
5069         declaration->type = type;
5070
5071         rem_anchor_token('{');
5072 }
5073
5074 static bool first_err = true;
5075
5076 /**
5077  * When called with first_err set, prints the name of the current function,
5078  * else does noting.
5079  */
5080 static void print_in_function(void)
5081 {
5082         if (first_err) {
5083                 first_err = false;
5084                 diagnosticf("%s: In function '%Y':\n",
5085                         current_function->source_position.input_name,
5086                         current_function->symbol);
5087         }
5088 }
5089
5090 /**
5091  * Check if all labels are defined in the current function.
5092  * Check if all labels are used in the current function.
5093  */
5094 static void check_labels(void)
5095 {
5096         for (const goto_statement_t *goto_statement = goto_first;
5097             goto_statement != NULL;
5098             goto_statement = goto_statement->next) {
5099                 /* skip computed gotos */
5100                 if (goto_statement->expression != NULL)
5101                         continue;
5102
5103                 declaration_t *label = goto_statement->label;
5104
5105                 label->used = true;
5106                 if (label->source_position.input_name == NULL) {
5107                         print_in_function();
5108                         errorf(&goto_statement->base.source_position,
5109                                "label '%Y' used but not defined", label->symbol);
5110                  }
5111         }
5112         goto_first = goto_last = NULL;
5113
5114         if (warning.unused_label) {
5115                 for (const label_statement_t *label_statement = label_first;
5116                          label_statement != NULL;
5117                          label_statement = label_statement->next) {
5118                         const declaration_t *label = label_statement->label;
5119
5120                         if (! label->used) {
5121                                 print_in_function();
5122                                 warningf(&label_statement->base.source_position,
5123                                         "label '%Y' defined but not used", label->symbol);
5124                         }
5125                 }
5126         }
5127         label_first = label_last = NULL;
5128 }
5129
5130 static void warn_unused_decl(declaration_t *decl, declaration_t *end, char const *const what)
5131 {
5132         for (; decl != NULL; decl = decl->next) {
5133                 if (decl->implicit)
5134                         continue;
5135
5136                 if (!decl->used) {
5137                         print_in_function();
5138                         warningf(&decl->source_position, "%s '%Y' is unused", what, decl->symbol);
5139                 } else if (!decl->read) {
5140                         print_in_function();
5141                         warningf(&decl->source_position, "%s '%Y' is never read", what, decl->symbol);
5142                 }
5143
5144                 if (decl == end)
5145                         break;
5146         }
5147 }
5148
5149 static void check_unused_variables(statement_t *const stmt, void *const env)
5150 {
5151         (void)env;
5152
5153         switch (stmt->kind) {
5154                 case STATEMENT_DECLARATION: {
5155                         declaration_statement_t const *const decls = &stmt->declaration;
5156                         warn_unused_decl(decls->declarations_begin, decls->declarations_end, "variable");
5157                         return;
5158                 }
5159
5160                 case STATEMENT_FOR:
5161                         warn_unused_decl(stmt->fors.scope.declarations, NULL, "variable");
5162                         return;
5163
5164                 default:
5165                         return;
5166         }
5167 }
5168
5169 /**
5170  * Check declarations of current_function for unused entities.
5171  */
5172 static void check_declarations(void)
5173 {
5174         if (warning.unused_parameter) {
5175                 const scope_t *scope = &current_function->scope;
5176
5177                 /* do not issue unused warnings for main */
5178                 if (!is_sym_main(current_function->symbol)) {
5179                         warn_unused_decl(scope->declarations, NULL, "parameter");
5180                 }
5181         }
5182         if (warning.unused_variable) {
5183                 walk_statements(current_function->init.statement, check_unused_variables, NULL);
5184         }
5185 }
5186
5187 static int determine_truth(expression_t const* const cond)
5188 {
5189         return
5190                 !is_constant_expression(cond) ? 0 :
5191                 fold_constant(cond) != 0      ? 1 :
5192                 -1;
5193 }
5194
5195 static bool noreturn_candidate;
5196
5197 static void check_reachable(statement_t *const stmt)
5198 {
5199         if (stmt->base.reachable)
5200                 return;
5201         if (stmt->kind != STATEMENT_DO_WHILE)
5202                 stmt->base.reachable = true;
5203
5204         statement_t *last = stmt;
5205         statement_t *next;
5206         switch (stmt->kind) {
5207                 case STATEMENT_INVALID:
5208                 case STATEMENT_EMPTY:
5209                 case STATEMENT_DECLARATION:
5210                 case STATEMENT_ASM:
5211                         next = stmt->base.next;
5212                         break;
5213
5214                 case STATEMENT_COMPOUND:
5215                         next = stmt->compound.statements;
5216                         break;
5217
5218                 case STATEMENT_RETURN:
5219                         noreturn_candidate = false;
5220                         return;
5221
5222                 case STATEMENT_IF: {
5223                         if_statement_t const* const ifs = &stmt->ifs;
5224                         int            const        val = determine_truth(ifs->condition);
5225
5226                         if (val >= 0)
5227                                 check_reachable(ifs->true_statement);
5228
5229                         if (val > 0)
5230                                 return;
5231
5232                         if (ifs->false_statement != NULL) {
5233                                 check_reachable(ifs->false_statement);
5234                                 return;
5235                         }
5236
5237                         next = stmt->base.next;
5238                         break;
5239                 }
5240
5241                 case STATEMENT_SWITCH: {
5242                         switch_statement_t const *const switchs = &stmt->switchs;
5243                         expression_t       const *const expr    = switchs->expression;
5244
5245                         if (is_constant_expression(expr)) {
5246                                 long                    const val      = fold_constant(expr);
5247                                 case_label_statement_t *      defaults = NULL;
5248                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5249                                         if (i->expression == NULL) {
5250                                                 defaults = i;
5251                                                 continue;
5252                                         }
5253
5254                                         if (i->first_case <= val && val <= i->last_case) {
5255                                                 check_reachable((statement_t*)i);
5256                                                 return;
5257                                         }
5258                                 }
5259
5260                                 if (defaults != NULL) {
5261                                         check_reachable((statement_t*)defaults);
5262                                         return;
5263                                 }
5264                         } else {
5265                                 bool has_default = false;
5266                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5267                                         if (i->expression == NULL)
5268                                                 has_default = true;
5269
5270                                         check_reachable((statement_t*)i);
5271                                 }
5272
5273                                 if (has_default)
5274                                         return;
5275                         }
5276
5277                         next = stmt->base.next;
5278                         break;
5279                 }
5280
5281                 case STATEMENT_EXPRESSION: {
5282                         /* Check for noreturn function call */
5283                         expression_t const *const expr = stmt->expression.expression;
5284                         if (expr->kind == EXPR_CALL) {
5285                                 expression_t const *const func = expr->call.function;
5286                                 if (func->kind == EXPR_REFERENCE) {
5287                                         declaration_t const *const decl = func->reference.declaration;
5288                                         if (decl != NULL && decl->modifiers & DM_NORETURN) {
5289                                                 return;
5290                                         }
5291                                 }
5292                         }
5293
5294                         next = stmt->base.next;
5295                         break;
5296                 }
5297
5298                 case STATEMENT_CONTINUE: {
5299                         statement_t *parent = stmt;
5300                         for (;;) {
5301                                 parent = parent->base.parent;
5302                                 if (parent == NULL) /* continue not within loop */
5303                                         return;
5304
5305                                 next = parent;
5306                                 switch (parent->kind) {
5307                                         case STATEMENT_WHILE:    goto continue_while;
5308                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5309                                         case STATEMENT_FOR:      goto continue_for;
5310
5311                                         default: break;
5312                                 }
5313                         }
5314                 }
5315
5316                 case STATEMENT_BREAK: {
5317                         statement_t *parent = stmt;
5318                         for (;;) {
5319                                 parent = parent->base.parent;
5320                                 if (parent == NULL) /* break not within loop/switch */
5321                                         return;
5322
5323                                 switch (parent->kind) {
5324                                         case STATEMENT_SWITCH:
5325                                         case STATEMENT_WHILE:
5326                                         case STATEMENT_DO_WHILE:
5327                                         case STATEMENT_FOR:
5328                                                 last = parent;
5329                                                 next = parent->base.next;
5330                                                 goto found_break_parent;
5331
5332                                         default: break;
5333                                 }
5334                         }
5335 found_break_parent:
5336                         break;
5337                 }
5338
5339                 case STATEMENT_GOTO:
5340                         if (stmt->gotos.expression) {
5341                                 statement_t *parent = stmt->base.parent;
5342                                 if (parent == NULL) /* top level goto */
5343                                         return;
5344                                 next = parent;
5345                         } else {
5346                                 next = stmt->gotos.label->init.statement;
5347                                 if (next == NULL) /* missing label */
5348                                         return;
5349                         }
5350                         break;
5351
5352                 case STATEMENT_LABEL:
5353                         next = stmt->label.statement;
5354                         break;
5355
5356                 case STATEMENT_CASE_LABEL:
5357                         next = stmt->case_label.statement;
5358                         break;
5359
5360                 case STATEMENT_WHILE: {
5361                         while_statement_t const *const whiles = &stmt->whiles;
5362                         int                      const val    = determine_truth(whiles->condition);
5363
5364                         if (val >= 0)
5365                                 check_reachable(whiles->body);
5366
5367                         if (val > 0)
5368                                 return;
5369
5370                         next = stmt->base.next;
5371                         break;
5372                 }
5373
5374                 case STATEMENT_DO_WHILE:
5375                         next = stmt->do_while.body;
5376                         break;
5377
5378                 case STATEMENT_FOR: {
5379                         for_statement_t *const fors = &stmt->fors;
5380
5381                         if (fors->condition_reachable)
5382                                 return;
5383                         fors->condition_reachable = true;
5384
5385                         expression_t const *const cond = fors->condition;
5386                         int          const        val  =
5387                                 cond == NULL ? 1 : determine_truth(cond);
5388
5389                         if (val >= 0)
5390                                 check_reachable(fors->body);
5391
5392                         if (val > 0)
5393                                 return;
5394
5395                         next = stmt->base.next;
5396                         break;
5397                 }
5398
5399                 case STATEMENT_MS_TRY: {
5400                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5401                         check_reachable(ms_try->try_statement);
5402                         next = ms_try->final_statement;
5403                         break;
5404                 }
5405
5406                 case STATEMENT_LEAVE: {
5407                         statement_t *parent = stmt;
5408                         for (;;) {
5409                                 parent = parent->base.parent;
5410                                 if (parent == NULL) /* __leave not within __try */
5411                                         return;
5412
5413                                 if (parent->kind == STATEMENT_MS_TRY) {
5414                                         last = parent;
5415                                         next = parent->ms_try.final_statement;
5416                                         break;
5417                                 }
5418                         }
5419                         break;
5420                 }
5421         }
5422
5423         while (next == NULL) {
5424                 next = last->base.parent;
5425                 if (next == NULL) {
5426                         noreturn_candidate = false;
5427
5428                         type_t *const type = current_function->type;
5429                         assert(is_type_function(type));
5430                         type_t *const ret  = skip_typeref(type->function.return_type);
5431                         if (warning.return_type                    &&
5432                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
5433                             is_type_valid(ret)                     &&
5434                             !is_sym_main(current_function->symbol)) {
5435                                 warningf(&stmt->base.source_position,
5436                                          "control reaches end of non-void function");
5437                         }
5438                         return;
5439                 }
5440
5441                 switch (next->kind) {
5442                         case STATEMENT_INVALID:
5443                         case STATEMENT_EMPTY:
5444                         case STATEMENT_DECLARATION:
5445                         case STATEMENT_EXPRESSION:
5446                         case STATEMENT_ASM:
5447                         case STATEMENT_RETURN:
5448                         case STATEMENT_CONTINUE:
5449                         case STATEMENT_BREAK:
5450                         case STATEMENT_GOTO:
5451                         case STATEMENT_LEAVE:
5452                                 panic("invalid control flow in function");
5453
5454                         case STATEMENT_COMPOUND:
5455                         case STATEMENT_IF:
5456                         case STATEMENT_SWITCH:
5457                         case STATEMENT_LABEL:
5458                         case STATEMENT_CASE_LABEL:
5459                                 last = next;
5460                                 next = next->base.next;
5461                                 break;
5462
5463                         case STATEMENT_WHILE: {
5464 continue_while:
5465                                 if (next->base.reachable)
5466                                         return;
5467                                 next->base.reachable = true;
5468
5469                                 while_statement_t const *const whiles = &next->whiles;
5470                                 int                      const val    = determine_truth(whiles->condition);
5471
5472                                 if (val >= 0)
5473                                         check_reachable(whiles->body);
5474
5475                                 if (val > 0)
5476                                         return;
5477
5478                                 last = next;
5479                                 next = next->base.next;
5480                                 break;
5481                         }
5482
5483                         case STATEMENT_DO_WHILE: {
5484 continue_do_while:
5485                                 if (next->base.reachable)
5486                                         return;
5487                                 next->base.reachable = true;
5488
5489                                 do_while_statement_t const *const dw  = &next->do_while;
5490                                 int                  const        val = determine_truth(dw->condition);
5491
5492                                 if (val >= 0)
5493                                         check_reachable(dw->body);
5494
5495                                 if (val > 0)
5496                                         return;
5497
5498                                 last = next;
5499                                 next = next->base.next;
5500                                 break;
5501                         }
5502
5503                         case STATEMENT_FOR: {
5504 continue_for:;
5505                                 for_statement_t *const fors = &next->fors;
5506
5507                                 fors->step_reachable = true;
5508
5509                                 if (fors->condition_reachable)
5510                                         return;
5511                                 fors->condition_reachable = true;
5512
5513                                 expression_t const *const cond = fors->condition;
5514                                 int          const        val  =
5515                                         cond == NULL ? 1 : determine_truth(cond);
5516
5517                                 if (val >= 0)
5518                                         check_reachable(fors->body);
5519
5520                                 if (val > 0)
5521                                         return;
5522
5523                                 last = next;
5524                                 next = next->base.next;
5525                                 break;
5526                         }
5527
5528                         case STATEMENT_MS_TRY:
5529                                 last = next;
5530                                 next = next->ms_try.final_statement;
5531                                 break;
5532                 }
5533         }
5534
5535         if (next == NULL) {
5536                 next = stmt->base.parent;
5537                 if (next == NULL) {
5538                         warningf(&stmt->base.source_position,
5539                                  "control reaches end of non-void function");
5540                 }
5541         }
5542
5543         check_reachable(next);
5544 }
5545
5546 static void check_unreachable(statement_t* const stmt, void *const env)
5547 {
5548         (void)env;
5549
5550         switch (stmt->kind) {
5551                 case STATEMENT_DO_WHILE:
5552                         if (!stmt->base.reachable) {
5553                                 expression_t const *const cond = stmt->do_while.condition;
5554                                 if (determine_truth(cond) >= 0) {
5555                                         warningf(&cond->base.source_position,
5556                                                  "condition of do-while-loop is unreachable");
5557                                 }
5558                         }
5559                         return;
5560
5561                 case STATEMENT_FOR: {
5562                         for_statement_t const* const fors = &stmt->fors;
5563
5564                         // if init and step are unreachable, cond is unreachable, too
5565                         if (!stmt->base.reachable && !fors->step_reachable) {
5566                                 warningf(&stmt->base.source_position, "statement is unreachable");
5567                         } else {
5568                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5569                                         warningf(&fors->initialisation->base.source_position,
5570                                                  "initialisation of for-statement is unreachable");
5571                                 }
5572
5573                                 if (!fors->condition_reachable && fors->condition != NULL) {
5574                                         warningf(&fors->condition->base.source_position,
5575                                                  "condition of for-statement is unreachable");
5576                                 }
5577
5578                                 if (!fors->step_reachable && fors->step != NULL) {
5579                                         warningf(&fors->step->base.source_position,
5580                                                  "step of for-statement is unreachable");
5581                                 }
5582                         }
5583                         return;
5584                 }
5585
5586                 case STATEMENT_COMPOUND:
5587                         if (stmt->compound.statements != NULL)
5588                                 return;
5589                         /* FALLTHROUGH*/
5590
5591                 default:
5592                         if (!stmt->base.reachable)
5593                                 warningf(&stmt->base.source_position, "statement is unreachable");
5594                         return;
5595         }
5596 }
5597
5598 static void parse_external_declaration(void)
5599 {
5600         /* function-definitions and declarations both start with declaration
5601          * specifiers */
5602         declaration_specifiers_t specifiers;
5603         memset(&specifiers, 0, sizeof(specifiers));
5604
5605         add_anchor_token(';');
5606         parse_declaration_specifiers(&specifiers);
5607         rem_anchor_token(';');
5608
5609         /* must be a declaration */
5610         if (token.type == ';') {
5611                 parse_anonymous_declaration_rest(&specifiers);
5612                 return;
5613         }
5614
5615         add_anchor_token(',');
5616         add_anchor_token('=');
5617         add_anchor_token(';');
5618         add_anchor_token('{');
5619
5620         /* declarator is common to both function-definitions and declarations */
5621         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5622
5623         rem_anchor_token('{');
5624         rem_anchor_token(';');
5625         rem_anchor_token('=');
5626         rem_anchor_token(',');
5627
5628         /* must be a declaration */
5629         switch (token.type) {
5630                 case ',':
5631                 case ';':
5632                 case '=':
5633                         parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
5634                         return;
5635         }
5636
5637         /* must be a function definition */
5638         parse_kr_declaration_list(ndeclaration);
5639
5640         if (token.type != '{') {
5641                 parse_error_expected("while parsing function definition", '{', NULL);
5642                 eat_until_matching_token(';');
5643                 return;
5644         }
5645
5646         type_t *type = ndeclaration->type;
5647
5648         /* note that we don't skip typerefs: the standard doesn't allow them here
5649          * (so we can't use is_type_function here) */
5650         if (type->kind != TYPE_FUNCTION) {
5651                 if (is_type_valid(type)) {
5652                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5653                                type, ndeclaration->symbol);
5654                 }
5655                 eat_block();
5656                 return;
5657         }
5658
5659         if (warning.aggregate_return &&
5660             is_type_compound(skip_typeref(type->function.return_type))) {
5661                 warningf(HERE, "function '%Y' returns an aggregate",
5662                          ndeclaration->symbol);
5663         }
5664         if (warning.traditional && !type->function.unspecified_parameters) {
5665                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
5666                         ndeclaration->symbol);
5667         }
5668         if (warning.old_style_definition && type->function.unspecified_parameters) {
5669                 warningf(HERE, "old-style function definition '%Y'",
5670                         ndeclaration->symbol);
5671         }
5672
5673         /* Â§ 6.7.5.3 (14) a function definition with () means no
5674          * parameters (and not unspecified parameters) */
5675         if (type->function.unspecified_parameters
5676                         && type->function.parameters == NULL
5677                         && !type->function.kr_style_parameters) {
5678                 type_t *duplicate = duplicate_type(type);
5679                 duplicate->function.unspecified_parameters = false;
5680
5681                 type = typehash_insert(duplicate);
5682                 if (type != duplicate) {
5683                         obstack_free(type_obst, duplicate);
5684                 }
5685                 ndeclaration->type = type;
5686         }
5687
5688         declaration_t *const declaration = record_declaration(ndeclaration, true);
5689         if (ndeclaration != declaration) {
5690                 declaration->scope = ndeclaration->scope;
5691         }
5692         type = skip_typeref(declaration->type);
5693
5694         /* push function parameters and switch scope */
5695         size_t const top = environment_top();
5696         scope_push(&declaration->scope);
5697
5698         declaration_t *parameter = declaration->scope.declarations;
5699         for( ; parameter != NULL; parameter = parameter->next) {
5700                 if (parameter->parent_scope == &ndeclaration->scope) {
5701                         parameter->parent_scope = scope;
5702                 }
5703                 assert(parameter->parent_scope == NULL
5704                                 || parameter->parent_scope == scope);
5705                 parameter->parent_scope = scope;
5706                 if (parameter->symbol == NULL) {
5707                         errorf(&parameter->source_position, "parameter name omitted");
5708                         continue;
5709                 }
5710                 environment_push(parameter);
5711         }
5712
5713         if (declaration->init.statement != NULL) {
5714                 parser_error_multiple_definition(declaration, HERE);
5715                 eat_block();
5716         } else {
5717                 /* parse function body */
5718                 int            label_stack_top      = label_top();
5719                 declaration_t *old_current_function = current_function;
5720                 current_function                    = declaration;
5721                 current_parent                      = NULL;
5722
5723                 statement_t *const body = parse_compound_statement(false);
5724                 declaration->init.statement = body;
5725                 first_err = true;
5726                 check_labels();
5727                 check_declarations();
5728                 if (warning.return_type      ||
5729                     warning.unreachable_code ||
5730                     (warning.missing_noreturn && !(declaration->modifiers & DM_NORETURN))) {
5731                         noreturn_candidate = true;
5732                         check_reachable(body);
5733                         if (warning.unreachable_code)
5734                                 walk_statements(body, check_unreachable, NULL);
5735                         if (warning.missing_noreturn &&
5736                             noreturn_candidate       &&
5737                             !(declaration->modifiers & DM_NORETURN)) {
5738                                 warningf(&body->base.source_position,
5739                                          "function '%#T' is candidate for attribute 'noreturn'",
5740                                          type, declaration->symbol);
5741                         }
5742                 }
5743
5744                 assert(current_parent   == NULL);
5745                 assert(current_function == declaration);
5746                 current_function = old_current_function;
5747                 label_pop_to(label_stack_top);
5748         }
5749
5750         assert(scope == &declaration->scope);
5751         scope_pop();
5752         environment_pop_to(top);
5753 }
5754
5755 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5756                                   source_position_t *source_position,
5757                                   const symbol_t *symbol)
5758 {
5759         type_t *type = allocate_type_zero(TYPE_BITFIELD, source_position);
5760
5761         type->bitfield.base_type       = base_type;
5762         type->bitfield.size_expression = size;
5763
5764         il_size_t bit_size;
5765         type_t *skipped_type = skip_typeref(base_type);
5766         if (!is_type_integer(skipped_type)) {
5767                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5768                         base_type);
5769                 bit_size = 0;
5770         } else {
5771                 bit_size = skipped_type->base.size * 8;
5772         }
5773
5774         if (is_constant_expression(size)) {
5775                 long v = fold_constant(size);
5776
5777                 if (v < 0) {
5778                         errorf(source_position, "negative width in bit-field '%Y'",
5779                                 symbol);
5780                 } else if (v == 0) {
5781                         errorf(source_position, "zero width for bit-field '%Y'",
5782                                 symbol);
5783                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
5784                         errorf(source_position, "width of '%Y' exceeds its type",
5785                                 symbol);
5786                 } else {
5787                         type->bitfield.bit_size = v;
5788                 }
5789         }
5790
5791         return type;
5792 }
5793
5794 static declaration_t *find_compound_entry(declaration_t *compound_declaration,
5795                                           symbol_t *symbol)
5796 {
5797         declaration_t *iter = compound_declaration->scope.declarations;
5798         for( ; iter != NULL; iter = iter->next) {
5799                 if (iter->namespc != NAMESPACE_NORMAL)
5800                         continue;
5801
5802                 if (iter->symbol == NULL) {
5803                         type_t *type = skip_typeref(iter->type);
5804                         if (is_type_compound(type)) {
5805                                 declaration_t *result
5806                                         = find_compound_entry(type->compound.declaration, symbol);
5807                                 if (result != NULL)
5808                                         return result;
5809                         }
5810                         continue;
5811                 }
5812
5813                 if (iter->symbol == symbol) {
5814                         return iter;
5815                 }
5816         }
5817
5818         return NULL;
5819 }
5820
5821 static void parse_compound_declarators(declaration_t *struct_declaration,
5822                 const declaration_specifiers_t *specifiers)
5823 {
5824         declaration_t *last_declaration = struct_declaration->scope.declarations;
5825         if (last_declaration != NULL) {
5826                 while (last_declaration->next != NULL) {
5827                         last_declaration = last_declaration->next;
5828                 }
5829         }
5830
5831         while (true) {
5832                 declaration_t *declaration;
5833
5834                 if (token.type == ':') {
5835                         source_position_t source_position = *HERE;
5836                         next_token();
5837
5838                         type_t *base_type = specifiers->type;
5839                         expression_t *size = parse_constant_expression();
5840
5841                         type_t *type = make_bitfield_type(base_type, size,
5842                                         &source_position, sym_anonymous);
5843
5844                         declaration                         = allocate_declaration_zero();
5845                         declaration->namespc                = NAMESPACE_NORMAL;
5846                         declaration->declared_storage_class = STORAGE_CLASS_NONE;
5847                         declaration->storage_class          = STORAGE_CLASS_NONE;
5848                         declaration->source_position        = source_position;
5849                         declaration->modifiers              = specifiers->modifiers;
5850                         declaration->type                   = type;
5851                 } else {
5852                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
5853
5854                         type_t *orig_type = declaration->type;
5855                         type_t *type      = skip_typeref(orig_type);
5856
5857                         if (token.type == ':') {
5858                                 source_position_t source_position = *HERE;
5859                                 next_token();
5860                                 expression_t *size = parse_constant_expression();
5861
5862                                 type_t *bitfield_type = make_bitfield_type(orig_type, size,
5863                                                 &source_position, declaration->symbol);
5864                                 declaration->type = bitfield_type;
5865                         } else {
5866                                 /* TODO we ignore arrays for now... what is missing is a check
5867                                  * that they're at the end of the struct */
5868                                 if (is_type_incomplete(type) && !is_type_array(type)) {
5869                                         errorf(HERE,
5870                                                "compound member '%Y' has incomplete type '%T'",
5871                                                declaration->symbol, orig_type);
5872                                 } else if (is_type_function(type)) {
5873                                         errorf(HERE, "compound member '%Y' must not have function type '%T'",
5874                                                declaration->symbol, orig_type);
5875                                 }
5876                         }
5877                 }
5878
5879                 /* make sure we don't define a symbol multiple times */
5880                 symbol_t *symbol = declaration->symbol;
5881                 if (symbol != NULL) {
5882                         declaration_t *prev_decl
5883                                 = find_compound_entry(struct_declaration, symbol);
5884
5885                         if (prev_decl != NULL) {
5886                                 assert(prev_decl->symbol == symbol);
5887                                 errorf(&declaration->source_position,
5888                                        "multiple declarations of symbol '%Y' (declared %P)",
5889                                        symbol, &prev_decl->source_position);
5890                         }
5891                 }
5892
5893                 /* append declaration */
5894                 if (last_declaration != NULL) {
5895                         last_declaration->next = declaration;
5896                 } else {
5897                         struct_declaration->scope.declarations = declaration;
5898                 }
5899                 last_declaration = declaration;
5900
5901                 if (token.type != ',')
5902                         break;
5903                 next_token();
5904         }
5905         expect(';');
5906
5907 end_error:
5908         ;
5909 }
5910
5911 static void parse_compound_type_entries(declaration_t *compound_declaration)
5912 {
5913         eat('{');
5914         add_anchor_token('}');
5915
5916         while (token.type != '}') {
5917                 if (token.type == T_EOF) {
5918                         errorf(HERE, "EOF while parsing struct");
5919                         break;
5920                 }
5921                 declaration_specifiers_t specifiers;
5922                 memset(&specifiers, 0, sizeof(specifiers));
5923                 parse_declaration_specifiers(&specifiers);
5924
5925                 parse_compound_declarators(compound_declaration, &specifiers);
5926         }
5927         rem_anchor_token('}');
5928         next_token();
5929 }
5930
5931 static type_t *parse_typename(void)
5932 {
5933         declaration_specifiers_t specifiers;
5934         memset(&specifiers, 0, sizeof(specifiers));
5935         parse_declaration_specifiers(&specifiers);
5936         if (specifiers.declared_storage_class != STORAGE_CLASS_NONE) {
5937                 /* TODO: improve error message, user does probably not know what a
5938                  * storage class is...
5939                  */
5940                 errorf(HERE, "typename may not have a storage class");
5941         }
5942
5943         type_t *result = parse_abstract_declarator(specifiers.type);
5944
5945         return result;
5946 }
5947
5948
5949
5950
5951 typedef expression_t* (*parse_expression_function) (unsigned precedence);
5952 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
5953                                                           expression_t *left);
5954
5955 typedef struct expression_parser_function_t expression_parser_function_t;
5956 struct expression_parser_function_t {
5957         unsigned                         precedence;
5958         parse_expression_function        parser;
5959         unsigned                         infix_precedence;
5960         parse_expression_infix_function  infix_parser;
5961 };
5962
5963 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5964
5965 /**
5966  * Prints an error message if an expression was expected but not read
5967  */
5968 static expression_t *expected_expression_error(void)
5969 {
5970         /* skip the error message if the error token was read */
5971         if (token.type != T_ERROR) {
5972                 errorf(HERE, "expected expression, got token '%K'", &token);
5973         }
5974         next_token();
5975
5976         return create_invalid_expression();
5977 }
5978
5979 /**
5980  * Parse a string constant.
5981  */
5982 static expression_t *parse_string_const(void)
5983 {
5984         wide_string_t wres;
5985         if (token.type == T_STRING_LITERAL) {
5986                 string_t res = token.v.string;
5987                 next_token();
5988                 while (token.type == T_STRING_LITERAL) {
5989                         res = concat_strings(&res, &token.v.string);
5990                         next_token();
5991                 }
5992                 if (token.type != T_WIDE_STRING_LITERAL) {
5993                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
5994                         /* note: that we use type_char_ptr here, which is already the
5995                          * automatic converted type. revert_automatic_type_conversion
5996                          * will construct the array type */
5997                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
5998                         cnst->string.value = res;
5999                         return cnst;
6000                 }
6001
6002                 wres = concat_string_wide_string(&res, &token.v.wide_string);
6003         } else {
6004                 wres = token.v.wide_string;
6005         }
6006         next_token();
6007
6008         for (;;) {
6009                 switch (token.type) {
6010                         case T_WIDE_STRING_LITERAL:
6011                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
6012                                 break;
6013
6014                         case T_STRING_LITERAL:
6015                                 wres = concat_wide_string_string(&wres, &token.v.string);
6016                                 break;
6017
6018                         default: {
6019                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6020                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
6021                                 cnst->wide_string.value = wres;
6022                                 return cnst;
6023                         }
6024                 }
6025                 next_token();
6026         }
6027 }
6028
6029 /**
6030  * Parse an integer constant.
6031  */
6032 static expression_t *parse_int_const(void)
6033 {
6034         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6035         cnst->base.source_position = *HERE;
6036         cnst->base.type            = token.datatype;
6037         cnst->conste.v.int_value   = token.v.intvalue;
6038
6039         next_token();
6040
6041         return cnst;
6042 }
6043
6044 /**
6045  * Parse a character constant.
6046  */
6047 static expression_t *parse_character_constant(void)
6048 {
6049         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
6050
6051         cnst->base.source_position = *HERE;
6052         cnst->base.type            = token.datatype;
6053         cnst->conste.v.character   = token.v.string;
6054
6055         if (cnst->conste.v.character.size != 1) {
6056                 if (warning.multichar && GNU_MODE) {
6057                         warningf(HERE, "multi-character character constant");
6058                 } else {
6059                         errorf(HERE, "more than 1 characters in character constant");
6060                 }
6061         }
6062         next_token();
6063
6064         return cnst;
6065 }
6066
6067 /**
6068  * Parse a wide character constant.
6069  */
6070 static expression_t *parse_wide_character_constant(void)
6071 {
6072         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
6073
6074         cnst->base.source_position    = *HERE;
6075         cnst->base.type               = token.datatype;
6076         cnst->conste.v.wide_character = token.v.wide_string;
6077
6078         if (cnst->conste.v.wide_character.size != 1) {
6079                 if (warning.multichar && GNU_MODE) {
6080                         warningf(HERE, "multi-character character constant");
6081                 } else {
6082                         errorf(HERE, "more than 1 characters in character constant");
6083                 }
6084         }
6085         next_token();
6086
6087         return cnst;
6088 }
6089
6090 /**
6091  * Parse a float constant.
6092  */
6093 static expression_t *parse_float_const(void)
6094 {
6095         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6096         cnst->base.type            = token.datatype;
6097         cnst->conste.v.float_value = token.v.floatvalue;
6098
6099         next_token();
6100
6101         return cnst;
6102 }
6103
6104 static declaration_t *create_implicit_function(symbol_t *symbol,
6105                 const source_position_t *source_position)
6106 {
6107         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION, source_position);
6108         ntype->function.return_type            = type_int;
6109         ntype->function.unspecified_parameters = true;
6110
6111         type_t *type = typehash_insert(ntype);
6112         if (type != ntype) {
6113                 free_type(ntype);
6114         }
6115
6116         declaration_t *const declaration    = allocate_declaration_zero();
6117         declaration->storage_class          = STORAGE_CLASS_EXTERN;
6118         declaration->declared_storage_class = STORAGE_CLASS_EXTERN;
6119         declaration->type                   = type;
6120         declaration->symbol                 = symbol;
6121         declaration->source_position        = *source_position;
6122         declaration->implicit               = true;
6123
6124         bool strict_prototypes_old = warning.strict_prototypes;
6125         warning.strict_prototypes  = false;
6126         record_declaration(declaration, false);
6127         warning.strict_prototypes = strict_prototypes_old;
6128
6129         return declaration;
6130 }
6131
6132 /**
6133  * Creates a return_type (func)(argument_type) function type if not
6134  * already exists.
6135  */
6136 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
6137                                     type_t *argument_type2)
6138 {
6139         function_parameter_t *parameter2
6140                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
6141         memset(parameter2, 0, sizeof(parameter2[0]));
6142         parameter2->type = argument_type2;
6143
6144         function_parameter_t *parameter1
6145                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
6146         memset(parameter1, 0, sizeof(parameter1[0]));
6147         parameter1->type = argument_type1;
6148         parameter1->next = parameter2;
6149
6150         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
6151         type->function.return_type = return_type;
6152         type->function.parameters  = parameter1;
6153
6154         type_t *result = typehash_insert(type);
6155         if (result != type) {
6156                 free_type(type);
6157         }
6158
6159         return result;
6160 }
6161
6162 /**
6163  * Creates a return_type (func)(argument_type) function type if not
6164  * already exists.
6165  *
6166  * @param return_type    the return type
6167  * @param argument_type  the argument type
6168  */
6169 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
6170 {
6171         function_parameter_t *parameter
6172                 = obstack_alloc(type_obst, sizeof(parameter[0]));
6173         memset(parameter, 0, sizeof(parameter[0]));
6174         parameter->type = argument_type;
6175
6176         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
6177         type->function.return_type = return_type;
6178         type->function.parameters  = parameter;
6179
6180         type_t *result = typehash_insert(type);
6181         if (result != type) {
6182                 free_type(type);
6183         }
6184
6185         return result;
6186 }
6187
6188 static type_t *make_function_0_type(type_t *return_type)
6189 {
6190         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
6191         type->function.return_type = return_type;
6192         type->function.parameters  = NULL;
6193
6194         type_t *result = typehash_insert(type);
6195         if (result != type) {
6196                 free_type(type);
6197         }
6198
6199         return result;
6200 }
6201
6202 /**
6203  * Creates a function type for some function like builtins.
6204  *
6205  * @param symbol   the symbol describing the builtin
6206  */
6207 static type_t *get_builtin_symbol_type(symbol_t *symbol)
6208 {
6209         switch(symbol->ID) {
6210         case T___builtin_alloca:
6211                 return make_function_1_type(type_void_ptr, type_size_t);
6212         case T___builtin_huge_val:
6213                 return make_function_0_type(type_double);
6214         case T___builtin_inf:
6215                 return make_function_0_type(type_double);
6216         case T___builtin_inff:
6217                 return make_function_0_type(type_float);
6218         case T___builtin_infl:
6219                 return make_function_0_type(type_long_double);
6220         case T___builtin_nan:
6221                 return make_function_1_type(type_double, type_char_ptr);
6222         case T___builtin_nanf:
6223                 return make_function_1_type(type_float, type_char_ptr);
6224         case T___builtin_nanl:
6225                 return make_function_1_type(type_long_double, type_char_ptr);
6226         case T___builtin_va_end:
6227                 return make_function_1_type(type_void, type_valist);
6228         case T___builtin_expect:
6229                 return make_function_2_type(type_long, type_long, type_long);
6230         default:
6231                 internal_errorf(HERE, "not implemented builtin symbol found");
6232         }
6233 }
6234
6235 /**
6236  * Performs automatic type cast as described in Â§ 6.3.2.1.
6237  *
6238  * @param orig_type  the original type
6239  */
6240 static type_t *automatic_type_conversion(type_t *orig_type)
6241 {
6242         type_t *type = skip_typeref(orig_type);
6243         if (is_type_array(type)) {
6244                 array_type_t *array_type   = &type->array;
6245                 type_t       *element_type = array_type->element_type;
6246                 unsigned      qualifiers   = array_type->base.qualifiers;
6247
6248                 return make_pointer_type(element_type, qualifiers);
6249         }
6250
6251         if (is_type_function(type)) {
6252                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6253         }
6254
6255         return orig_type;
6256 }
6257
6258 /**
6259  * reverts the automatic casts of array to pointer types and function
6260  * to function-pointer types as defined Â§ 6.3.2.1
6261  */
6262 type_t *revert_automatic_type_conversion(const expression_t *expression)
6263 {
6264         switch (expression->kind) {
6265                 case EXPR_REFERENCE: return expression->reference.declaration->type;
6266
6267                 case EXPR_SELECT:
6268                         return get_qualified_type(expression->select.compound_entry->type,
6269                                                   expression->base.type->base.qualifiers);
6270
6271                 case EXPR_UNARY_DEREFERENCE: {
6272                         const expression_t *const value = expression->unary.value;
6273                         type_t             *const type  = skip_typeref(value->base.type);
6274                         assert(is_type_pointer(type));
6275                         return type->pointer.points_to;
6276                 }
6277
6278                 case EXPR_BUILTIN_SYMBOL:
6279                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
6280
6281                 case EXPR_ARRAY_ACCESS: {
6282                         const expression_t *array_ref = expression->array_access.array_ref;
6283                         type_t             *type_left = skip_typeref(array_ref->base.type);
6284                         if (!is_type_valid(type_left))
6285                                 return type_left;
6286                         assert(is_type_pointer(type_left));
6287                         return type_left->pointer.points_to;
6288                 }
6289
6290                 case EXPR_STRING_LITERAL: {
6291                         size_t size = expression->string.value.size;
6292                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6293                 }
6294
6295                 case EXPR_WIDE_STRING_LITERAL: {
6296                         size_t size = expression->wide_string.value.size;
6297                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6298                 }
6299
6300                 case EXPR_COMPOUND_LITERAL:
6301                         return expression->compound_literal.type;
6302
6303                 default: break;
6304         }
6305
6306         return expression->base.type;
6307 }
6308
6309 static expression_t *parse_reference(void)
6310 {
6311         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
6312
6313         reference_expression_t *ref = &expression->reference;
6314         symbol_t *const symbol = token.v.symbol;
6315
6316         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
6317
6318         if (declaration == NULL) {
6319                 if (!strict_mode && look_ahead(1)->type == '(') {
6320                         /* an implicitly declared function */
6321                         if (warning.implicit_function_declaration) {
6322                                 warningf(HERE, "implicit declaration of function '%Y'",
6323                                         symbol);
6324                         }
6325
6326                         declaration = create_implicit_function(symbol, HERE);
6327                 } else {
6328                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
6329                         declaration = create_error_declaration(symbol, STORAGE_CLASS_NONE);
6330                 }
6331         }
6332
6333         type_t *orig_type = declaration->type;
6334
6335         /* we always do the auto-type conversions; the & and sizeof parser contains
6336          * code to revert this! */
6337         type_t *type = automatic_type_conversion(orig_type);
6338
6339         ref->declaration = declaration;
6340         ref->base.type   = type;
6341
6342         /* this declaration is used */
6343         declaration->used = true;
6344
6345         if (declaration->parent_scope != file_scope                          &&
6346             declaration->parent_scope->depth < current_function->scope.depth &&
6347             is_type_valid(orig_type) && !is_type_function(orig_type)) {
6348                 /* access of a variable from an outer function */
6349                 declaration->address_taken     = true;
6350                 ref->is_outer_ref              = true;
6351                 current_function->need_closure = true;
6352         }
6353
6354         /* check for deprecated functions */
6355         if (warning.deprecated_declarations &&
6356             declaration->modifiers & DM_DEPRECATED) {
6357                 char const *const prefix = is_type_function(declaration->type) ?
6358                         "function" : "variable";
6359
6360                 if (declaration->deprecated_string != NULL) {
6361                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
6362                                 prefix, declaration->symbol, &declaration->source_position,
6363                                 declaration->deprecated_string);
6364                 } else {
6365                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
6366                                 declaration->symbol, &declaration->source_position);
6367                 }
6368         }
6369         if (warning.init_self && declaration == current_init_decl && !in_type_prop) {
6370                 current_init_decl = NULL;
6371                 warningf(HERE, "variable '%#T' is initialized by itself",
6372                         declaration->type, declaration->symbol);
6373         }
6374
6375         next_token();
6376         return expression;
6377 }
6378
6379 static bool semantic_cast(expression_t *cast)
6380 {
6381         expression_t            *expression      = cast->unary.value;
6382         type_t                  *orig_dest_type  = cast->base.type;
6383         type_t                  *orig_type_right = expression->base.type;
6384         type_t            const *dst_type        = skip_typeref(orig_dest_type);
6385         type_t            const *src_type        = skip_typeref(orig_type_right);
6386         source_position_t const *pos             = &cast->base.source_position;
6387
6388         /* Â§6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
6389         if (dst_type == type_void)
6390                 return true;
6391
6392         /* only integer and pointer can be casted to pointer */
6393         if (is_type_pointer(dst_type)  &&
6394             !is_type_pointer(src_type) &&
6395             !is_type_integer(src_type) &&
6396             is_type_valid(src_type)) {
6397                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
6398                 return false;
6399         }
6400
6401         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
6402                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
6403                 return false;
6404         }
6405
6406         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
6407                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
6408                 return false;
6409         }
6410
6411         if (warning.cast_qual &&
6412             is_type_pointer(src_type) &&
6413             is_type_pointer(dst_type)) {
6414                 type_t *src = skip_typeref(src_type->pointer.points_to);
6415                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
6416                 unsigned missing_qualifiers =
6417                         src->base.qualifiers & ~dst->base.qualifiers;
6418                 if (missing_qualifiers != 0) {
6419                         warningf(pos,
6420                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
6421                                  missing_qualifiers, orig_type_right);
6422                 }
6423         }
6424         return true;
6425 }
6426
6427 static expression_t *parse_compound_literal(type_t *type)
6428 {
6429         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
6430
6431         parse_initializer_env_t env;
6432         env.type             = type;
6433         env.declaration      = NULL;
6434         env.must_be_constant = false;
6435         initializer_t *initializer = parse_initializer(&env);
6436         type = env.type;
6437
6438         expression->compound_literal.initializer = initializer;
6439         expression->compound_literal.type        = type;
6440         expression->base.type                    = automatic_type_conversion(type);
6441
6442         return expression;
6443 }
6444
6445 /**
6446  * Parse a cast expression.
6447  */
6448 static expression_t *parse_cast(void)
6449 {
6450         add_anchor_token(')');
6451
6452         source_position_t source_position = token.source_position;
6453
6454         type_t *type  = parse_typename();
6455
6456         rem_anchor_token(')');
6457         expect(')');
6458
6459         if (token.type == '{') {
6460                 return parse_compound_literal(type);
6461         }
6462
6463         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
6464         cast->base.source_position = source_position;
6465
6466         expression_t *value = parse_sub_expression(20);
6467         cast->base.type   = type;
6468         cast->unary.value = value;
6469
6470         if (! semantic_cast(cast)) {
6471                 /* TODO: record the error in the AST. else it is impossible to detect it */
6472         }
6473
6474         return cast;
6475 end_error:
6476         return create_invalid_expression();
6477 }
6478
6479 /**
6480  * Parse a statement expression.
6481  */
6482 static expression_t *parse_statement_expression(void)
6483 {
6484         add_anchor_token(')');
6485
6486         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
6487
6488         statement_t *statement           = parse_compound_statement(true);
6489         expression->statement.statement  = statement;
6490         expression->base.source_position = statement->base.source_position;
6491
6492         /* find last statement and use its type */
6493         type_t *type = type_void;
6494         const statement_t *stmt = statement->compound.statements;
6495         if (stmt != NULL) {
6496                 while (stmt->base.next != NULL)
6497                         stmt = stmt->base.next;
6498
6499                 if (stmt->kind == STATEMENT_EXPRESSION) {
6500                         type = stmt->expression.expression->base.type;
6501                 }
6502         } else {
6503                 warningf(&expression->base.source_position, "empty statement expression ({})");
6504         }
6505         expression->base.type = type;
6506
6507         rem_anchor_token(')');
6508         expect(')');
6509
6510 end_error:
6511         return expression;
6512 }
6513
6514 /**
6515  * Parse a parenthesized expression.
6516  */
6517 static expression_t *parse_parenthesized_expression(void)
6518 {
6519         eat('(');
6520
6521         switch(token.type) {
6522         case '{':
6523                 /* gcc extension: a statement expression */
6524                 return parse_statement_expression();
6525
6526         TYPE_QUALIFIERS
6527         TYPE_SPECIFIERS
6528                 return parse_cast();
6529         case T_IDENTIFIER:
6530                 if (is_typedef_symbol(token.v.symbol)) {
6531                         return parse_cast();
6532                 }
6533         }
6534
6535         add_anchor_token(')');
6536         expression_t *result = parse_expression();
6537         rem_anchor_token(')');
6538         expect(')');
6539
6540 end_error:
6541         return result;
6542 }
6543
6544 static expression_t *parse_function_keyword(void)
6545 {
6546         next_token();
6547         /* TODO */
6548
6549         if (current_function == NULL) {
6550                 errorf(HERE, "'__func__' used outside of a function");
6551         }
6552
6553         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6554         expression->base.type     = type_char_ptr;
6555         expression->funcname.kind = FUNCNAME_FUNCTION;
6556
6557         return expression;
6558 }
6559
6560 static expression_t *parse_pretty_function_keyword(void)
6561 {
6562         eat(T___PRETTY_FUNCTION__);
6563
6564         if (current_function == NULL) {
6565                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
6566         }
6567
6568         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6569         expression->base.type     = type_char_ptr;
6570         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
6571
6572         return expression;
6573 }
6574
6575 static expression_t *parse_funcsig_keyword(void)
6576 {
6577         eat(T___FUNCSIG__);
6578
6579         if (current_function == NULL) {
6580                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
6581         }
6582
6583         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6584         expression->base.type     = type_char_ptr;
6585         expression->funcname.kind = FUNCNAME_FUNCSIG;
6586
6587         return expression;
6588 }
6589
6590 static expression_t *parse_funcdname_keyword(void)
6591 {
6592         eat(T___FUNCDNAME__);
6593
6594         if (current_function == NULL) {
6595                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6596         }
6597
6598         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6599         expression->base.type     = type_char_ptr;
6600         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6601
6602         return expression;
6603 }
6604
6605 static designator_t *parse_designator(void)
6606 {
6607         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6608         result->source_position = *HERE;
6609
6610         if (token.type != T_IDENTIFIER) {
6611                 parse_error_expected("while parsing member designator",
6612                                      T_IDENTIFIER, NULL);
6613                 return NULL;
6614         }
6615         result->symbol = token.v.symbol;
6616         next_token();
6617
6618         designator_t *last_designator = result;
6619         while(true) {
6620                 if (token.type == '.') {
6621                         next_token();
6622                         if (token.type != T_IDENTIFIER) {
6623                                 parse_error_expected("while parsing member designator",
6624                                                      T_IDENTIFIER, NULL);
6625                                 return NULL;
6626                         }
6627                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6628                         designator->source_position = *HERE;
6629                         designator->symbol          = token.v.symbol;
6630                         next_token();
6631
6632                         last_designator->next = designator;
6633                         last_designator       = designator;
6634                         continue;
6635                 }
6636                 if (token.type == '[') {
6637                         next_token();
6638                         add_anchor_token(']');
6639                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6640                         designator->source_position = *HERE;
6641                         designator->array_index     = parse_expression();
6642                         rem_anchor_token(']');
6643                         expect(']');
6644                         if (designator->array_index == NULL) {
6645                                 return NULL;
6646                         }
6647
6648                         last_designator->next = designator;
6649                         last_designator       = designator;
6650                         continue;
6651                 }
6652                 break;
6653         }
6654
6655         return result;
6656 end_error:
6657         return NULL;
6658 }
6659
6660 /**
6661  * Parse the __builtin_offsetof() expression.
6662  */
6663 static expression_t *parse_offsetof(void)
6664 {
6665         eat(T___builtin_offsetof);
6666
6667         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6668         expression->base.type    = type_size_t;
6669
6670         expect('(');
6671         add_anchor_token(',');
6672         type_t *type = parse_typename();
6673         rem_anchor_token(',');
6674         expect(',');
6675         add_anchor_token(')');
6676         designator_t *designator = parse_designator();
6677         rem_anchor_token(')');
6678         expect(')');
6679
6680         expression->offsetofe.type       = type;
6681         expression->offsetofe.designator = designator;
6682
6683         type_path_t path;
6684         memset(&path, 0, sizeof(path));
6685         path.top_type = type;
6686         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6687
6688         descend_into_subtype(&path);
6689
6690         if (!walk_designator(&path, designator, true)) {
6691                 return create_invalid_expression();
6692         }
6693
6694         DEL_ARR_F(path.path);
6695
6696         return expression;
6697 end_error:
6698         return create_invalid_expression();
6699 }
6700
6701 /**
6702  * Parses a _builtin_va_start() expression.
6703  */
6704 static expression_t *parse_va_start(void)
6705 {
6706         eat(T___builtin_va_start);
6707
6708         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6709
6710         expect('(');
6711         add_anchor_token(',');
6712         expression->va_starte.ap = parse_assignment_expression();
6713         rem_anchor_token(',');
6714         expect(',');
6715         expression_t *const expr = parse_assignment_expression();
6716         if (expr->kind == EXPR_REFERENCE) {
6717                 declaration_t *const decl = expr->reference.declaration;
6718                 if (decl->parent_scope != &current_function->scope || decl->next != NULL) {
6719                         errorf(&expr->base.source_position,
6720                                "second argument of 'va_start' must be last parameter of the current function");
6721                 }
6722                 expression->va_starte.parameter = decl;
6723                 expect(')');
6724                 return expression;
6725         }
6726         expect(')');
6727 end_error:
6728         return create_invalid_expression();
6729 }
6730
6731 /**
6732  * Parses a _builtin_va_arg() expression.
6733  */
6734 static expression_t *parse_va_arg(void)
6735 {
6736         eat(T___builtin_va_arg);
6737
6738         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6739
6740         expect('(');
6741         expression->va_arge.ap = parse_assignment_expression();
6742         expect(',');
6743         expression->base.type = parse_typename();
6744         expect(')');
6745
6746         return expression;
6747 end_error:
6748         return create_invalid_expression();
6749 }
6750
6751 static expression_t *parse_builtin_symbol(void)
6752 {
6753         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
6754
6755         symbol_t *symbol = token.v.symbol;
6756
6757         expression->builtin_symbol.symbol = symbol;
6758         next_token();
6759
6760         type_t *type = get_builtin_symbol_type(symbol);
6761         type = automatic_type_conversion(type);
6762
6763         expression->base.type = type;
6764         return expression;
6765 }
6766
6767 /**
6768  * Parses a __builtin_constant() expression.
6769  */
6770 static expression_t *parse_builtin_constant(void)
6771 {
6772         eat(T___builtin_constant_p);
6773
6774         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6775
6776         expect('(');
6777         add_anchor_token(')');
6778         expression->builtin_constant.value = parse_assignment_expression();
6779         rem_anchor_token(')');
6780         expect(')');
6781         expression->base.type = type_int;
6782
6783         return expression;
6784 end_error:
6785         return create_invalid_expression();
6786 }
6787
6788 /**
6789  * Parses a __builtin_prefetch() expression.
6790  */
6791 static expression_t *parse_builtin_prefetch(void)
6792 {
6793         eat(T___builtin_prefetch);
6794
6795         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
6796
6797         expect('(');
6798         add_anchor_token(')');
6799         expression->builtin_prefetch.adr = parse_assignment_expression();
6800         if (token.type == ',') {
6801                 next_token();
6802                 expression->builtin_prefetch.rw = parse_assignment_expression();
6803         }
6804         if (token.type == ',') {
6805                 next_token();
6806                 expression->builtin_prefetch.locality = parse_assignment_expression();
6807         }
6808         rem_anchor_token(')');
6809         expect(')');
6810         expression->base.type = type_void;
6811
6812         return expression;
6813 end_error:
6814         return create_invalid_expression();
6815 }
6816
6817 /**
6818  * Parses a __builtin_is_*() compare expression.
6819  */
6820 static expression_t *parse_compare_builtin(void)
6821 {
6822         expression_t *expression;
6823
6824         switch(token.type) {
6825         case T___builtin_isgreater:
6826                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6827                 break;
6828         case T___builtin_isgreaterequal:
6829                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6830                 break;
6831         case T___builtin_isless:
6832                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6833                 break;
6834         case T___builtin_islessequal:
6835                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6836                 break;
6837         case T___builtin_islessgreater:
6838                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6839                 break;
6840         case T___builtin_isunordered:
6841                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6842                 break;
6843         default:
6844                 internal_errorf(HERE, "invalid compare builtin found");
6845         }
6846         expression->base.source_position = *HERE;
6847         next_token();
6848
6849         expect('(');
6850         expression->binary.left = parse_assignment_expression();
6851         expect(',');
6852         expression->binary.right = parse_assignment_expression();
6853         expect(')');
6854
6855         type_t *const orig_type_left  = expression->binary.left->base.type;
6856         type_t *const orig_type_right = expression->binary.right->base.type;
6857
6858         type_t *const type_left  = skip_typeref(orig_type_left);
6859         type_t *const type_right = skip_typeref(orig_type_right);
6860         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6861                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6862                         type_error_incompatible("invalid operands in comparison",
6863                                 &expression->base.source_position, orig_type_left, orig_type_right);
6864                 }
6865         } else {
6866                 semantic_comparison(&expression->binary);
6867         }
6868
6869         return expression;
6870 end_error:
6871         return create_invalid_expression();
6872 }
6873
6874 #if 0
6875 /**
6876  * Parses a __builtin_expect() expression.
6877  */
6878 static expression_t *parse_builtin_expect(void)
6879 {
6880         eat(T___builtin_expect);
6881
6882         expression_t *expression
6883                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
6884
6885         expect('(');
6886         expression->binary.left = parse_assignment_expression();
6887         expect(',');
6888         expression->binary.right = parse_constant_expression();
6889         expect(')');
6890
6891         expression->base.type = expression->binary.left->base.type;
6892
6893         return expression;
6894 end_error:
6895         return create_invalid_expression();
6896 }
6897 #endif
6898
6899 /**
6900  * Parses a MS assume() expression.
6901  */
6902 static expression_t *parse_assume(void)
6903 {
6904         eat(T__assume);
6905
6906         expression_t *expression
6907                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
6908
6909         expect('(');
6910         add_anchor_token(')');
6911         expression->unary.value = parse_assignment_expression();
6912         rem_anchor_token(')');
6913         expect(')');
6914
6915         expression->base.type = type_void;
6916         return expression;
6917 end_error:
6918         return create_invalid_expression();
6919 }
6920
6921 /**
6922  * Return the declaration for a given label symbol or create a new one.
6923  *
6924  * @param symbol  the symbol of the label
6925  */
6926 static declaration_t *get_label(symbol_t *symbol)
6927 {
6928         declaration_t *candidate;
6929         assert(current_function != NULL);
6930
6931         candidate = get_declaration(symbol, NAMESPACE_LOCAL_LABEL);
6932         /* if we found a local label, we already created the declaration */
6933         if (candidate != NULL) {
6934                 if (candidate->parent_scope != scope) {
6935                         assert(candidate->parent_scope->depth < scope->depth);
6936                         current_function->goto_to_outer = true;
6937                 }
6938                 return candidate;
6939         }
6940
6941         candidate = get_declaration(symbol, NAMESPACE_LABEL);
6942         /* if we found a label in the same function, then we already created the
6943          * declaration */
6944         if (candidate != NULL
6945                         && candidate->parent_scope == &current_function->scope) {
6946                 return candidate;
6947         }
6948
6949         /* otherwise we need to create a new one */
6950         declaration_t *const declaration = allocate_declaration_zero();
6951         declaration->namespc       = NAMESPACE_LABEL;
6952         declaration->symbol        = symbol;
6953
6954         label_push(declaration);
6955
6956         return declaration;
6957 }
6958
6959 /**
6960  * Parses a GNU && label address expression.
6961  */
6962 static expression_t *parse_label_address(void)
6963 {
6964         source_position_t source_position = token.source_position;
6965         eat(T_ANDAND);
6966         if (token.type != T_IDENTIFIER) {
6967                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
6968                 goto end_error;
6969         }
6970         symbol_t *symbol = token.v.symbol;
6971         next_token();
6972
6973         declaration_t *label = get_label(symbol);
6974
6975         label->used          = true;
6976         label->address_taken = true;
6977
6978         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
6979         expression->base.source_position = source_position;
6980
6981         /* label address is threaten as a void pointer */
6982         expression->base.type                 = type_void_ptr;
6983         expression->label_address.declaration = label;
6984         return expression;
6985 end_error:
6986         return create_invalid_expression();
6987 }
6988
6989 /**
6990  * Parse a microsoft __noop expression.
6991  */
6992 static expression_t *parse_noop_expression(void)
6993 {
6994         source_position_t source_position = *HERE;
6995         eat(T___noop);
6996
6997         if (token.type == '(') {
6998                 /* parse arguments */
6999                 eat('(');
7000                 add_anchor_token(')');
7001                 add_anchor_token(',');
7002
7003                 if (token.type != ')') {
7004                         while(true) {
7005                                 (void)parse_assignment_expression();
7006                                 if (token.type != ',')
7007                                         break;
7008                                 next_token();
7009                         }
7010                 }
7011         }
7012         rem_anchor_token(',');
7013         rem_anchor_token(')');
7014         expect(')');
7015
7016         /* the result is a (int)0 */
7017         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
7018         cnst->base.source_position = source_position;
7019         cnst->base.type            = type_int;
7020         cnst->conste.v.int_value   = 0;
7021         cnst->conste.is_ms_noop    = true;
7022
7023         return cnst;
7024
7025 end_error:
7026         return create_invalid_expression();
7027 }
7028
7029 /**
7030  * Parses a primary expression.
7031  */
7032 static expression_t *parse_primary_expression(void)
7033 {
7034         switch (token.type) {
7035                 case T_INTEGER:                  return parse_int_const();
7036                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
7037                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
7038                 case T_FLOATINGPOINT:            return parse_float_const();
7039                 case T_STRING_LITERAL:
7040                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
7041                 case T_IDENTIFIER:               return parse_reference();
7042                 case T___FUNCTION__:
7043                 case T___func__:                 return parse_function_keyword();
7044                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
7045                 case T___FUNCSIG__:              return parse_funcsig_keyword();
7046                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
7047                 case T___builtin_offsetof:       return parse_offsetof();
7048                 case T___builtin_va_start:       return parse_va_start();
7049                 case T___builtin_va_arg:         return parse_va_arg();
7050                 case T___builtin_expect:
7051                 case T___builtin_alloca:
7052                 case T___builtin_inf:
7053                 case T___builtin_inff:
7054                 case T___builtin_infl:
7055                 case T___builtin_nan:
7056                 case T___builtin_nanf:
7057                 case T___builtin_nanl:
7058                 case T___builtin_huge_val:
7059                 case T___builtin_va_end:         return parse_builtin_symbol();
7060                 case T___builtin_isgreater:
7061                 case T___builtin_isgreaterequal:
7062                 case T___builtin_isless:
7063                 case T___builtin_islessequal:
7064                 case T___builtin_islessgreater:
7065                 case T___builtin_isunordered:    return parse_compare_builtin();
7066                 case T___builtin_constant_p:     return parse_builtin_constant();
7067                 case T___builtin_prefetch:       return parse_builtin_prefetch();
7068                 case T__assume:                  return parse_assume();
7069                 case T_ANDAND:
7070                         if (GNU_MODE)
7071                                 return parse_label_address();
7072                         break;
7073
7074                 case '(':                        return parse_parenthesized_expression();
7075                 case T___noop:                   return parse_noop_expression();
7076         }
7077
7078         errorf(HERE, "unexpected token %K, expected an expression", &token);
7079         return create_invalid_expression();
7080 }
7081
7082 /**
7083  * Check if the expression has the character type and issue a warning then.
7084  */
7085 static void check_for_char_index_type(const expression_t *expression)
7086 {
7087         type_t       *const type      = expression->base.type;
7088         const type_t *const base_type = skip_typeref(type);
7089
7090         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7091                         warning.char_subscripts) {
7092                 warningf(&expression->base.source_position,
7093                          "array subscript has type '%T'", type);
7094         }
7095 }
7096
7097 static expression_t *parse_array_expression(unsigned precedence,
7098                                             expression_t *left)
7099 {
7100         (void) precedence;
7101
7102         eat('[');
7103         add_anchor_token(']');
7104
7105         expression_t *inside = parse_expression();
7106
7107         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7108
7109         array_access_expression_t *array_access = &expression->array_access;
7110
7111         type_t *const orig_type_left   = left->base.type;
7112         type_t *const orig_type_inside = inside->base.type;
7113
7114         type_t *const type_left   = skip_typeref(orig_type_left);
7115         type_t *const type_inside = skip_typeref(orig_type_inside);
7116
7117         type_t *return_type;
7118         if (is_type_pointer(type_left)) {
7119                 return_type             = type_left->pointer.points_to;
7120                 array_access->array_ref = left;
7121                 array_access->index     = inside;
7122                 check_for_char_index_type(inside);
7123         } else if (is_type_pointer(type_inside)) {
7124                 return_type             = type_inside->pointer.points_to;
7125                 array_access->array_ref = inside;
7126                 array_access->index     = left;
7127                 array_access->flipped   = true;
7128                 check_for_char_index_type(left);
7129         } else {
7130                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7131                         errorf(HERE,
7132                                 "array access on object with non-pointer types '%T', '%T'",
7133                                 orig_type_left, orig_type_inside);
7134                 }
7135                 return_type             = type_error_type;
7136                 array_access->array_ref = left;
7137                 array_access->index     = inside;
7138         }
7139
7140         expression->base.type = automatic_type_conversion(return_type);
7141
7142         rem_anchor_token(']');
7143         if (token.type == ']') {
7144                 next_token();
7145         } else {
7146                 parse_error_expected("Problem while parsing array access", ']', NULL);
7147         }
7148         return expression;
7149 }
7150
7151 static expression_t *parse_typeprop(expression_kind_t const kind,
7152                                     source_position_t const pos,
7153                                     unsigned const precedence)
7154 {
7155         expression_t  *tp_expression = allocate_expression_zero(kind);
7156         tp_expression->base.type            = type_size_t;
7157         tp_expression->base.source_position = pos;
7158
7159         char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7160
7161         /* we only refer to a type property, mark this case */
7162         bool old     = in_type_prop;
7163         in_type_prop = true;
7164         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7165                 next_token();
7166                 add_anchor_token(')');
7167                 type_t* const orig_type = parse_typename();
7168                 tp_expression->typeprop.type = orig_type;
7169
7170                 type_t const* const type = skip_typeref(orig_type);
7171                 char const* const wrong_type =
7172                         is_type_incomplete(type)    ? "incomplete"          :
7173                         type->kind == TYPE_FUNCTION ? "function designator" :
7174                         type->kind == TYPE_BITFIELD ? "bitfield"            :
7175                         NULL;
7176                 if (wrong_type != NULL) {
7177                         errorf(&pos, "operand of %s expression must not be %s type '%T'",
7178                                what, wrong_type, type);
7179                 }
7180
7181                 rem_anchor_token(')');
7182                 expect(')');
7183         } else {
7184                 expression_t *expression = parse_sub_expression(precedence);
7185
7186                 type_t* const orig_type = revert_automatic_type_conversion(expression);
7187                 expression->base.type = orig_type;
7188
7189                 type_t const* const type = skip_typeref(orig_type);
7190                 char const* const wrong_type =
7191                         is_type_incomplete(type)    ? "incomplete"          :
7192                         type->kind == TYPE_FUNCTION ? "function designator" :
7193                         type->kind == TYPE_BITFIELD ? "bitfield"            :
7194                         NULL;
7195                 if (wrong_type != NULL) {
7196                         errorf(&pos, "operand of %s expression must not be expression of %s type '%T'", what, wrong_type, type);
7197                 }
7198
7199                 tp_expression->typeprop.type          = expression->base.type;
7200                 tp_expression->typeprop.tp_expression = expression;
7201         }
7202
7203 end_error:
7204         in_type_prop = old;
7205         return tp_expression;
7206 }
7207
7208 static expression_t *parse_sizeof(unsigned precedence)
7209 {
7210         source_position_t pos = *HERE;
7211         eat(T_sizeof);
7212         return parse_typeprop(EXPR_SIZEOF, pos, precedence);
7213 }
7214
7215 static expression_t *parse_alignof(unsigned precedence)
7216 {
7217         source_position_t pos = *HERE;
7218         eat(T___alignof__);
7219         return parse_typeprop(EXPR_ALIGNOF, pos, precedence);
7220 }
7221
7222 static expression_t *parse_select_expression(unsigned precedence,
7223                                              expression_t *compound)
7224 {
7225         (void) precedence;
7226         assert(token.type == '.' || token.type == T_MINUSGREATER);
7227
7228         bool is_pointer = (token.type == T_MINUSGREATER);
7229         next_token();
7230
7231         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
7232         select->select.compound = compound;
7233
7234         if (token.type != T_IDENTIFIER) {
7235                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7236                 return select;
7237         }
7238         symbol_t *symbol = token.v.symbol;
7239         next_token();
7240
7241         type_t *const orig_type = compound->base.type;
7242         type_t *const type      = skip_typeref(orig_type);
7243
7244         type_t *type_left;
7245         bool    saw_error = false;
7246         if (is_type_pointer(type)) {
7247                 if (!is_pointer) {
7248                         errorf(HERE,
7249                                "request for member '%Y' in something not a struct or union, but '%T'",
7250                                symbol, orig_type);
7251                         saw_error = true;
7252                 }
7253                 type_left = skip_typeref(type->pointer.points_to);
7254         } else {
7255                 if (is_pointer && is_type_valid(type)) {
7256                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7257                         saw_error = true;
7258                 }
7259                 type_left = type;
7260         }
7261
7262         declaration_t *entry;
7263         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
7264             type_left->kind == TYPE_COMPOUND_UNION) {
7265                 declaration_t *const declaration = type_left->compound.declaration;
7266
7267                 if (!declaration->init.complete) {
7268                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
7269                                symbol, type_left);
7270                         goto create_error_entry;
7271                 }
7272
7273                 entry = find_compound_entry(declaration, symbol);
7274                 if (entry == NULL) {
7275                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
7276                         goto create_error_entry;
7277                 }
7278         } else {
7279                 if (is_type_valid(type_left) && !saw_error) {
7280                         errorf(HERE,
7281                                "request for member '%Y' in something not a struct or union, but '%T'",
7282                                symbol, type_left);
7283                 }
7284 create_error_entry:
7285                 entry         = allocate_declaration_zero();
7286                 entry->symbol = symbol;
7287         }
7288
7289         select->select.compound_entry = entry;
7290
7291         type_t *const res_type =
7292                 get_qualified_type(entry->type, type_left->base.qualifiers);
7293
7294         /* we always do the auto-type conversions; the & and sizeof parser contains
7295          * code to revert this! */
7296         select->base.type = automatic_type_conversion(res_type);
7297
7298         type_t *skipped = skip_typeref(res_type);
7299         if (skipped->kind == TYPE_BITFIELD) {
7300                 select->base.type = skipped->bitfield.base_type;
7301         }
7302
7303         return select;
7304 }
7305
7306 static void check_call_argument(const function_parameter_t *parameter,
7307                                 call_argument_t *argument, unsigned pos)
7308 {
7309         type_t         *expected_type      = parameter->type;
7310         type_t         *expected_type_skip = skip_typeref(expected_type);
7311         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7312         expression_t   *arg_expr           = argument->expression;
7313         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7314
7315         /* handle transparent union gnu extension */
7316         if (is_type_union(expected_type_skip)
7317                         && (expected_type_skip->base.modifiers
7318                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
7319                 declaration_t  *union_decl = expected_type_skip->compound.declaration;
7320
7321                 declaration_t *declaration = union_decl->scope.declarations;
7322                 type_t        *best_type   = NULL;
7323                 for ( ; declaration != NULL; declaration = declaration->next) {
7324                         type_t *decl_type = declaration->type;
7325                         error = semantic_assign(decl_type, arg_expr);
7326                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7327                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
7328                                 continue;
7329
7330                         if (error == ASSIGN_SUCCESS) {
7331                                 best_type = decl_type;
7332                         } else if (best_type == NULL) {
7333                                 best_type = decl_type;
7334                         }
7335                 }
7336
7337                 if (best_type != NULL) {
7338                         expected_type = best_type;
7339                 }
7340         }
7341
7342         error                = semantic_assign(expected_type, arg_expr);
7343         argument->expression = create_implicit_cast(argument->expression,
7344                                                     expected_type);
7345
7346         if (error != ASSIGN_SUCCESS) {
7347                 /* report exact scope in error messages (like "in argument 3") */
7348                 char buf[64];
7349                 snprintf(buf, sizeof(buf), "call argument %u", pos);
7350                 report_assign_error(error, expected_type, arg_expr,     buf,
7351                                                         &arg_expr->base.source_position);
7352         } else if (warning.traditional || warning.conversion) {
7353                 type_t *const promoted_type = get_default_promoted_type(arg_type);
7354                 if (!types_compatible(expected_type_skip, promoted_type) &&
7355                     !types_compatible(expected_type_skip, type_void_ptr) &&
7356                     !types_compatible(type_void_ptr,      promoted_type)) {
7357                         /* Deliberately show the skipped types in this warning */
7358                         warningf(&arg_expr->base.source_position,
7359                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
7360                                 pos, expected_type_skip, promoted_type);
7361                 }
7362         }
7363 }
7364
7365 /**
7366  * Parse a call expression, ie. expression '( ... )'.
7367  *
7368  * @param expression  the function address
7369  */
7370 static expression_t *parse_call_expression(unsigned precedence,
7371                                            expression_t *expression)
7372 {
7373         (void) precedence;
7374         expression_t *result = allocate_expression_zero(EXPR_CALL);
7375         result->base.source_position = expression->base.source_position;
7376
7377         call_expression_t *call = &result->call;
7378         call->function          = expression;
7379
7380         type_t *const orig_type = expression->base.type;
7381         type_t *const type      = skip_typeref(orig_type);
7382
7383         function_type_t *function_type = NULL;
7384         if (is_type_pointer(type)) {
7385                 type_t *const to_type = skip_typeref(type->pointer.points_to);
7386
7387                 if (is_type_function(to_type)) {
7388                         function_type   = &to_type->function;
7389                         call->base.type = function_type->return_type;
7390                 }
7391         }
7392
7393         if (function_type == NULL && is_type_valid(type)) {
7394                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
7395         }
7396
7397         /* parse arguments */
7398         eat('(');
7399         add_anchor_token(')');
7400         add_anchor_token(',');
7401
7402         if (token.type != ')') {
7403                 call_argument_t *last_argument = NULL;
7404
7405                 while (true) {
7406                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
7407
7408                         argument->expression = parse_assignment_expression();
7409                         if (last_argument == NULL) {
7410                                 call->arguments = argument;
7411                         } else {
7412                                 last_argument->next = argument;
7413                         }
7414                         last_argument = argument;
7415
7416                         if (token.type != ',')
7417                                 break;
7418                         next_token();
7419                 }
7420         }
7421         rem_anchor_token(',');
7422         rem_anchor_token(')');
7423         expect(')');
7424
7425         if (function_type == NULL)
7426                 return result;
7427
7428         function_parameter_t *parameter = function_type->parameters;
7429         call_argument_t      *argument  = call->arguments;
7430         if (!function_type->unspecified_parameters) {
7431                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
7432                                 parameter = parameter->next, argument = argument->next) {
7433                         check_call_argument(parameter, argument, ++pos);
7434                 }
7435
7436                 if (parameter != NULL) {
7437                         errorf(HERE, "too few arguments to function '%E'", expression);
7438                 } else if (argument != NULL && !function_type->variadic) {
7439                         errorf(HERE, "too many arguments to function '%E'", expression);
7440                 }
7441         }
7442
7443         /* do default promotion */
7444         for( ; argument != NULL; argument = argument->next) {
7445                 type_t *type = argument->expression->base.type;
7446
7447                 type = get_default_promoted_type(type);
7448
7449                 argument->expression
7450                         = create_implicit_cast(argument->expression, type);
7451         }
7452
7453         check_format(&result->call);
7454
7455         if (warning.aggregate_return &&
7456             is_type_compound(skip_typeref(function_type->return_type))) {
7457                 warningf(&result->base.source_position,
7458                          "function call has aggregate value");
7459         }
7460
7461 end_error:
7462         return result;
7463 }
7464
7465 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
7466
7467 static bool same_compound_type(const type_t *type1, const type_t *type2)
7468 {
7469         return
7470                 is_type_compound(type1) &&
7471                 type1->kind == type2->kind &&
7472                 type1->compound.declaration == type2->compound.declaration;
7473 }
7474
7475 /**
7476  * Parse a conditional expression, ie. 'expression ? ... : ...'.
7477  *
7478  * @param expression  the conditional expression
7479  */
7480 static expression_t *parse_conditional_expression(unsigned precedence,
7481                                                   expression_t *expression)
7482 {
7483         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
7484
7485         conditional_expression_t *conditional = &result->conditional;
7486         conditional->base.source_position = *HERE;
7487         conditional->condition            = expression;
7488
7489         eat('?');
7490         add_anchor_token(':');
7491
7492         /* 6.5.15.2 */
7493         type_t *const condition_type_orig = expression->base.type;
7494         type_t *const condition_type      = skip_typeref(condition_type_orig);
7495         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
7496                 type_error("expected a scalar type in conditional condition",
7497                            &expression->base.source_position, condition_type_orig);
7498         }
7499
7500         expression_t *true_expression = expression;
7501         bool          gnu_cond = false;
7502         if (GNU_MODE && token.type == ':') {
7503                 gnu_cond = true;
7504         } else
7505                 true_expression = parse_expression();
7506         rem_anchor_token(':');
7507         expect(':');
7508         expression_t *false_expression = parse_sub_expression(precedence);
7509
7510         type_t *const orig_true_type  = true_expression->base.type;
7511         type_t *const orig_false_type = false_expression->base.type;
7512         type_t *const true_type       = skip_typeref(orig_true_type);
7513         type_t *const false_type      = skip_typeref(orig_false_type);
7514
7515         /* 6.5.15.3 */
7516         type_t *result_type;
7517         if (is_type_atomic(true_type, ATOMIC_TYPE_VOID) ||
7518                 is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7519                 if (!is_type_atomic(true_type, ATOMIC_TYPE_VOID)
7520                     || !is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7521                         warningf(&conditional->base.source_position,
7522                                         "ISO C forbids conditional expression with only one void side");
7523                 }
7524                 result_type = type_void;
7525         } else if (is_type_arithmetic(true_type)
7526                    && is_type_arithmetic(false_type)) {
7527                 result_type = semantic_arithmetic(true_type, false_type);
7528
7529                 true_expression  = create_implicit_cast(true_expression, result_type);
7530                 false_expression = create_implicit_cast(false_expression, result_type);
7531
7532                 conditional->true_expression  = true_expression;
7533                 conditional->false_expression = false_expression;
7534                 conditional->base.type        = result_type;
7535         } else if (same_compound_type(true_type, false_type)) {
7536                 /* just take 1 of the 2 types */
7537                 result_type = true_type;
7538         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
7539                 type_t *pointer_type;
7540                 type_t *other_type;
7541                 expression_t *other_expression;
7542                 if (is_type_pointer(true_type) &&
7543                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
7544                         pointer_type     = true_type;
7545                         other_type       = false_type;
7546                         other_expression = false_expression;
7547                 } else {
7548                         pointer_type     = false_type;
7549                         other_type       = true_type;
7550                         other_expression = true_expression;
7551                 }
7552
7553                 if (is_null_pointer_constant(other_expression)) {
7554                         result_type = pointer_type;
7555                 } else if (is_type_pointer(other_type)) {
7556                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
7557                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
7558
7559                         type_t *to;
7560                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
7561                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
7562                                 to = type_void;
7563                         } else if (types_compatible(get_unqualified_type(to1),
7564                                                     get_unqualified_type(to2))) {
7565                                 to = to1;
7566                         } else {
7567                                 warningf(&conditional->base.source_position,
7568                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
7569                                         true_type, false_type);
7570                                 to = type_void;
7571                         }
7572
7573                         type_t *const type =
7574                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
7575                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
7576                 } else if (is_type_integer(other_type)) {
7577                         warningf(&conditional->base.source_position,
7578                                         "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
7579                         result_type = pointer_type;
7580                 } else {
7581                         if (is_type_valid(other_type)) {
7582                                 type_error_incompatible("while parsing conditional",
7583                                                 &expression->base.source_position, true_type, false_type);
7584                         }
7585                         result_type = type_error_type;
7586                 }
7587         } else {
7588                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
7589                         type_error_incompatible("while parsing conditional",
7590                                                 &conditional->base.source_position, true_type,
7591                                                 false_type);
7592                 }
7593                 result_type = type_error_type;
7594         }
7595
7596         conditional->true_expression
7597                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
7598         conditional->false_expression
7599                 = create_implicit_cast(false_expression, result_type);
7600         conditional->base.type = result_type;
7601         return result;
7602 end_error:
7603         return create_invalid_expression();
7604 }
7605
7606 /**
7607  * Parse an extension expression.
7608  */
7609 static expression_t *parse_extension(unsigned precedence)
7610 {
7611         eat(T___extension__);
7612
7613         bool old_gcc_extension   = in_gcc_extension;
7614         in_gcc_extension         = true;
7615         expression_t *expression = parse_sub_expression(precedence);
7616         in_gcc_extension         = old_gcc_extension;
7617         return expression;
7618 }
7619
7620 /**
7621  * Parse a __builtin_classify_type() expression.
7622  */
7623 static expression_t *parse_builtin_classify_type(const unsigned precedence)
7624 {
7625         eat(T___builtin_classify_type);
7626
7627         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
7628         result->base.type    = type_int;
7629
7630         expect('(');
7631         add_anchor_token(')');
7632         expression_t *expression = parse_sub_expression(precedence);
7633         rem_anchor_token(')');
7634         expect(')');
7635         result->classify_type.type_expression = expression;
7636
7637         return result;
7638 end_error:
7639         return create_invalid_expression();
7640 }
7641
7642 static bool check_pointer_arithmetic(const source_position_t *source_position,
7643                                      type_t *pointer_type,
7644                                      type_t *orig_pointer_type)
7645 {
7646         type_t *points_to = pointer_type->pointer.points_to;
7647         points_to = skip_typeref(points_to);
7648
7649         if (is_type_incomplete(points_to)) {
7650                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7651                         errorf(source_position,
7652                                "arithmetic with pointer to incomplete type '%T' not allowed",
7653                                orig_pointer_type);
7654                         return false;
7655                 } else if (warning.pointer_arith) {
7656                         warningf(source_position,
7657                                  "pointer of type '%T' used in arithmetic",
7658                                  orig_pointer_type);
7659                 }
7660         } else if (is_type_function(points_to)) {
7661                 if (!GNU_MODE) {
7662                         errorf(source_position,
7663                                "arithmetic with pointer to function type '%T' not allowed",
7664                                orig_pointer_type);
7665                         return false;
7666                 } else if (warning.pointer_arith) {
7667                         warningf(source_position,
7668                                  "pointer to a function '%T' used in arithmetic",
7669                                  orig_pointer_type);
7670                 }
7671         }
7672         return true;
7673 }
7674
7675 static bool is_lvalue(const expression_t *expression)
7676 {
7677         switch (expression->kind) {
7678         case EXPR_REFERENCE:
7679         case EXPR_ARRAY_ACCESS:
7680         case EXPR_SELECT:
7681         case EXPR_UNARY_DEREFERENCE:
7682                 return true;
7683
7684         default:
7685                 /* Claim it is an lvalue, if the type is invalid.  There was a parse
7686                  * error before, which maybe prevented properly recognizing it as
7687                  * lvalue. */
7688                 return !is_type_valid(skip_typeref(expression->base.type));
7689         }
7690 }
7691
7692 static void semantic_incdec(unary_expression_t *expression)
7693 {
7694         type_t *const orig_type = expression->value->base.type;
7695         type_t *const type      = skip_typeref(orig_type);
7696         if (is_type_pointer(type)) {
7697                 if (!check_pointer_arithmetic(&expression->base.source_position,
7698                                               type, orig_type)) {
7699                         return;
7700                 }
7701         } else if (!is_type_real(type) && is_type_valid(type)) {
7702                 /* TODO: improve error message */
7703                 errorf(&expression->base.source_position,
7704                        "operation needs an arithmetic or pointer type");
7705                 return;
7706         }
7707         if (!is_lvalue(expression->value)) {
7708                 /* TODO: improve error message */
7709                 errorf(&expression->base.source_position, "lvalue required as operand");
7710         }
7711         expression->base.type = orig_type;
7712 }
7713
7714 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
7715 {
7716         type_t *const orig_type = expression->value->base.type;
7717         type_t *const type      = skip_typeref(orig_type);
7718         if (!is_type_arithmetic(type)) {
7719                 if (is_type_valid(type)) {
7720                         /* TODO: improve error message */
7721                         errorf(&expression->base.source_position,
7722                                 "operation needs an arithmetic type");
7723                 }
7724                 return;
7725         }
7726
7727         expression->base.type = orig_type;
7728 }
7729
7730 static void semantic_unexpr_plus(unary_expression_t *expression)
7731 {
7732         semantic_unexpr_arithmetic(expression);
7733         if (warning.traditional)
7734                 warningf(&expression->base.source_position,
7735                         "traditional C rejects the unary plus operator");
7736 }
7737
7738 static expression_t const *get_reference_address(expression_t const *expr)
7739 {
7740         bool regular_take_address = true;
7741         for (;;) {
7742                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
7743                         expr = expr->unary.value;
7744                 } else {
7745                         regular_take_address = false;
7746                 }
7747
7748                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
7749                         break;
7750
7751                 expr = expr->unary.value;
7752         }
7753
7754         if (expr->kind != EXPR_REFERENCE)
7755                 return NULL;
7756
7757         if (!regular_take_address &&
7758             !is_type_function(skip_typeref(expr->reference.declaration->type))) {
7759                 return NULL;
7760         }
7761
7762         return expr;
7763 }
7764
7765 static void warn_function_address_as_bool(expression_t const* expr)
7766 {
7767         if (!warning.address)
7768                 return;
7769
7770         expr = get_reference_address(expr);
7771         if (expr != NULL) {
7772                 warningf(&expr->base.source_position,
7773                         "the address of '%Y' will always evaluate as 'true'",
7774                         expr->reference.declaration->symbol);
7775         }
7776 }
7777
7778 static void semantic_not(unary_expression_t *expression)
7779 {
7780         type_t *const orig_type = expression->value->base.type;
7781         type_t *const type      = skip_typeref(orig_type);
7782         if (!is_type_scalar(type) && is_type_valid(type)) {
7783                 errorf(&expression->base.source_position,
7784                        "operand of ! must be of scalar type");
7785         }
7786
7787         warn_function_address_as_bool(expression->value);
7788
7789         expression->base.type = type_int;
7790 }
7791
7792 static void semantic_unexpr_integer(unary_expression_t *expression)
7793 {
7794         type_t *const orig_type = expression->value->base.type;
7795         type_t *const type      = skip_typeref(orig_type);
7796         if (!is_type_integer(type)) {
7797                 if (is_type_valid(type)) {
7798                         errorf(&expression->base.source_position,
7799                                "operand of ~ must be of integer type");
7800                 }
7801                 return;
7802         }
7803
7804         expression->base.type = orig_type;
7805 }
7806
7807 static void semantic_dereference(unary_expression_t *expression)
7808 {
7809         type_t *const orig_type = expression->value->base.type;
7810         type_t *const type      = skip_typeref(orig_type);
7811         if (!is_type_pointer(type)) {
7812                 if (is_type_valid(type)) {
7813                         errorf(&expression->base.source_position,
7814                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
7815                 }
7816                 return;
7817         }
7818
7819         type_t *result_type   = type->pointer.points_to;
7820         result_type           = automatic_type_conversion(result_type);
7821         expression->base.type = result_type;
7822 }
7823
7824 /**
7825  * Record that an address is taken (expression represents an lvalue).
7826  *
7827  * @param expression       the expression
7828  * @param may_be_register  if true, the expression might be an register
7829  */
7830 static void set_address_taken(expression_t *expression, bool may_be_register)
7831 {
7832         if (expression->kind != EXPR_REFERENCE)
7833                 return;
7834
7835         declaration_t *const declaration = expression->reference.declaration;
7836         /* happens for parse errors */
7837         if (declaration == NULL)
7838                 return;
7839
7840         if (declaration->storage_class == STORAGE_CLASS_REGISTER && !may_be_register) {
7841                 errorf(&expression->base.source_position,
7842                                 "address of register variable '%Y' requested",
7843                                 declaration->symbol);
7844         } else {
7845                 declaration->address_taken = 1;
7846         }
7847 }
7848
7849 /**
7850  * Check the semantic of the address taken expression.
7851  */
7852 static void semantic_take_addr(unary_expression_t *expression)
7853 {
7854         expression_t *value = expression->value;
7855         value->base.type    = revert_automatic_type_conversion(value);
7856
7857         type_t *orig_type = value->base.type;
7858         if (!is_type_valid(skip_typeref(orig_type)))
7859                 return;
7860
7861         set_address_taken(value, false);
7862
7863         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
7864 }
7865
7866 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc)   \
7867 static expression_t *parse_##unexpression_type(unsigned precedence)            \
7868 {                                                                              \
7869         expression_t *unary_expression                                             \
7870                 = allocate_expression_zero(unexpression_type);                         \
7871         unary_expression->base.source_position = *HERE;                            \
7872         eat(token_type);                                                           \
7873         unary_expression->unary.value = parse_sub_expression(precedence);          \
7874                                                                                    \
7875         sfunc(&unary_expression->unary);                                           \
7876                                                                                    \
7877         return unary_expression;                                                   \
7878 }
7879
7880 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
7881                                semantic_unexpr_arithmetic)
7882 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
7883                                semantic_unexpr_plus)
7884 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
7885                                semantic_not)
7886 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
7887                                semantic_dereference)
7888 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
7889                                semantic_take_addr)
7890 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
7891                                semantic_unexpr_integer)
7892 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
7893                                semantic_incdec)
7894 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
7895                                semantic_incdec)
7896
7897 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
7898                                                sfunc)                         \
7899 static expression_t *parse_##unexpression_type(unsigned precedence,           \
7900                                                expression_t *left)            \
7901 {                                                                             \
7902         (void) precedence;                                                        \
7903                                                                               \
7904         expression_t *unary_expression                                            \
7905                 = allocate_expression_zero(unexpression_type);                        \
7906         unary_expression->base.source_position = *HERE;                           \
7907         eat(token_type);                                                          \
7908         unary_expression->unary.value          = left;                            \
7909                                                                                   \
7910         sfunc(&unary_expression->unary);                                          \
7911                                                                               \
7912         return unary_expression;                                                  \
7913 }
7914
7915 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
7916                                        EXPR_UNARY_POSTFIX_INCREMENT,
7917                                        semantic_incdec)
7918 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
7919                                        EXPR_UNARY_POSTFIX_DECREMENT,
7920                                        semantic_incdec)
7921
7922 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
7923 {
7924         /* TODO: handle complex + imaginary types */
7925
7926         type_left  = get_unqualified_type(type_left);
7927         type_right = get_unqualified_type(type_right);
7928
7929         /* Â§ 6.3.1.8 Usual arithmetic conversions */
7930         if (type_left == type_long_double || type_right == type_long_double) {
7931                 return type_long_double;
7932         } else if (type_left == type_double || type_right == type_double) {
7933                 return type_double;
7934         } else if (type_left == type_float || type_right == type_float) {
7935                 return type_float;
7936         }
7937
7938         type_left  = promote_integer(type_left);
7939         type_right = promote_integer(type_right);
7940
7941         if (type_left == type_right)
7942                 return type_left;
7943
7944         bool const signed_left  = is_type_signed(type_left);
7945         bool const signed_right = is_type_signed(type_right);
7946         int const  rank_left    = get_rank(type_left);
7947         int const  rank_right   = get_rank(type_right);
7948
7949         if (signed_left == signed_right)
7950                 return rank_left >= rank_right ? type_left : type_right;
7951
7952         int     s_rank;
7953         int     u_rank;
7954         type_t *s_type;
7955         type_t *u_type;
7956         if (signed_left) {
7957                 s_rank = rank_left;
7958                 s_type = type_left;
7959                 u_rank = rank_right;
7960                 u_type = type_right;
7961         } else {
7962                 s_rank = rank_right;
7963                 s_type = type_right;
7964                 u_rank = rank_left;
7965                 u_type = type_left;
7966         }
7967
7968         if (u_rank >= s_rank)
7969                 return u_type;
7970
7971         /* casting rank to atomic_type_kind is a bit hacky, but makes things
7972          * easier here... */
7973         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
7974                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
7975                 return s_type;
7976
7977         switch (s_rank) {
7978                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
7979                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
7980                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
7981
7982                 default: panic("invalid atomic type");
7983         }
7984 }
7985
7986 /**
7987  * Check the semantic restrictions for a binary expression.
7988  */
7989 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
7990 {
7991         expression_t *const left            = expression->left;
7992         expression_t *const right           = expression->right;
7993         type_t       *const orig_type_left  = left->base.type;
7994         type_t       *const orig_type_right = right->base.type;
7995         type_t       *const type_left       = skip_typeref(orig_type_left);
7996         type_t       *const type_right      = skip_typeref(orig_type_right);
7997
7998         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7999                 /* TODO: improve error message */
8000                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8001                         errorf(&expression->base.source_position,
8002                                "operation needs arithmetic types");
8003                 }
8004                 return;
8005         }
8006
8007         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8008         expression->left      = create_implicit_cast(left, arithmetic_type);
8009         expression->right     = create_implicit_cast(right, arithmetic_type);
8010         expression->base.type = arithmetic_type;
8011 }
8012
8013 static void warn_div_by_zero(binary_expression_t const *const expression)
8014 {
8015         if (!warning.div_by_zero ||
8016             !is_type_integer(expression->base.type))
8017                 return;
8018
8019         expression_t const *const right = expression->right;
8020         /* The type of the right operand can be different for /= */
8021         if (is_type_integer(right->base.type) &&
8022             is_constant_expression(right)     &&
8023             fold_constant(right) == 0) {
8024                 warningf(&expression->base.source_position, "division by zero");
8025         }
8026 }
8027
8028 /**
8029  * Check the semantic restrictions for a div/mod expression.
8030  */
8031 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
8032         semantic_binexpr_arithmetic(expression);
8033         warn_div_by_zero(expression);
8034 }
8035
8036 static void semantic_shift_op(binary_expression_t *expression)
8037 {
8038         expression_t *const left            = expression->left;
8039         expression_t *const right           = expression->right;
8040         type_t       *const orig_type_left  = left->base.type;
8041         type_t       *const orig_type_right = right->base.type;
8042         type_t       *      type_left       = skip_typeref(orig_type_left);
8043         type_t       *      type_right      = skip_typeref(orig_type_right);
8044
8045         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8046                 /* TODO: improve error message */
8047                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8048                         errorf(&expression->base.source_position,
8049                                "operands of shift operation must have integer types");
8050                 }
8051                 return;
8052         }
8053
8054         type_left  = promote_integer(type_left);
8055         type_right = promote_integer(type_right);
8056
8057         expression->left      = create_implicit_cast(left, type_left);
8058         expression->right     = create_implicit_cast(right, type_right);
8059         expression->base.type = type_left;
8060 }
8061
8062 static void semantic_add(binary_expression_t *expression)
8063 {
8064         expression_t *const left            = expression->left;
8065         expression_t *const right           = expression->right;
8066         type_t       *const orig_type_left  = left->base.type;
8067         type_t       *const orig_type_right = right->base.type;
8068         type_t       *const type_left       = skip_typeref(orig_type_left);
8069         type_t       *const type_right      = skip_typeref(orig_type_right);
8070
8071         /* Â§ 6.5.6 */
8072         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8073                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8074                 expression->left  = create_implicit_cast(left, arithmetic_type);
8075                 expression->right = create_implicit_cast(right, arithmetic_type);
8076                 expression->base.type = arithmetic_type;
8077                 return;
8078         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8079                 check_pointer_arithmetic(&expression->base.source_position,
8080                                          type_left, orig_type_left);
8081                 expression->base.type = type_left;
8082         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8083                 check_pointer_arithmetic(&expression->base.source_position,
8084                                          type_right, orig_type_right);
8085                 expression->base.type = type_right;
8086         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8087                 errorf(&expression->base.source_position,
8088                        "invalid operands to binary + ('%T', '%T')",
8089                        orig_type_left, orig_type_right);
8090         }
8091 }
8092
8093 static void semantic_sub(binary_expression_t *expression)
8094 {
8095         expression_t            *const left            = expression->left;
8096         expression_t            *const right           = expression->right;
8097         type_t                  *const orig_type_left  = left->base.type;
8098         type_t                  *const orig_type_right = right->base.type;
8099         type_t                  *const type_left       = skip_typeref(orig_type_left);
8100         type_t                  *const type_right      = skip_typeref(orig_type_right);
8101         source_position_t const *const pos             = &expression->base.source_position;
8102
8103         /* Â§ 5.6.5 */
8104         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8105                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8106                 expression->left        = create_implicit_cast(left, arithmetic_type);
8107                 expression->right       = create_implicit_cast(right, arithmetic_type);
8108                 expression->base.type =  arithmetic_type;
8109                 return;
8110         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8111                 check_pointer_arithmetic(&expression->base.source_position,
8112                                          type_left, orig_type_left);
8113                 expression->base.type = type_left;
8114         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8115                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8116                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8117                 if (!types_compatible(unqual_left, unqual_right)) {
8118                         errorf(pos,
8119                                "subtracting pointers to incompatible types '%T' and '%T'",
8120                                orig_type_left, orig_type_right);
8121                 } else if (!is_type_object(unqual_left)) {
8122                         if (is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8123                                 warningf(pos, "subtracting pointers to void");
8124                         } else {
8125                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8126                                        orig_type_left);
8127                         }
8128                 }
8129                 expression->base.type = type_ptrdiff_t;
8130         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8131                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
8132                        orig_type_left, orig_type_right);
8133         }
8134 }
8135
8136 static void warn_string_literal_address(expression_t const* expr)
8137 {
8138         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8139                 expr = expr->unary.value;
8140                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8141                         return;
8142                 expr = expr->unary.value;
8143         }
8144
8145         if (expr->kind == EXPR_STRING_LITERAL ||
8146             expr->kind == EXPR_WIDE_STRING_LITERAL) {
8147                 warningf(&expr->base.source_position,
8148                         "comparison with string literal results in unspecified behaviour");
8149         }
8150 }
8151
8152 /**
8153  * Check the semantics of comparison expressions.
8154  *
8155  * @param expression   The expression to check.
8156  */
8157 static void semantic_comparison(binary_expression_t *expression)
8158 {
8159         expression_t *left  = expression->left;
8160         expression_t *right = expression->right;
8161
8162         if (warning.address) {
8163                 warn_string_literal_address(left);
8164                 warn_string_literal_address(right);
8165
8166                 expression_t const* const func_left = get_reference_address(left);
8167                 if (func_left != NULL && is_null_pointer_constant(right)) {
8168                         warningf(&expression->base.source_position,
8169                                 "the address of '%Y' will never be NULL",
8170                                 func_left->reference.declaration->symbol);
8171                 }
8172
8173                 expression_t const* const func_right = get_reference_address(right);
8174                 if (func_right != NULL && is_null_pointer_constant(right)) {
8175                         warningf(&expression->base.source_position,
8176                                 "the address of '%Y' will never be NULL",
8177                                 func_right->reference.declaration->symbol);
8178                 }
8179         }
8180
8181         type_t *orig_type_left  = left->base.type;
8182         type_t *orig_type_right = right->base.type;
8183         type_t *type_left       = skip_typeref(orig_type_left);
8184         type_t *type_right      = skip_typeref(orig_type_right);
8185
8186         /* TODO non-arithmetic types */
8187         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8188                 /* test for signed vs unsigned compares */
8189                 if (warning.sign_compare &&
8190                     (expression->base.kind != EXPR_BINARY_EQUAL &&
8191                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
8192                     (is_type_signed(type_left) != is_type_signed(type_right))) {
8193
8194                         /* check if 1 of the operands is a constant, in this case we just
8195                          * check wether we can safely represent the resulting constant in
8196                          * the type of the other operand. */
8197                         expression_t *const_expr = NULL;
8198                         expression_t *other_expr = NULL;
8199
8200                         if (is_constant_expression(left)) {
8201                                 const_expr = left;
8202                                 other_expr = right;
8203                         } else if (is_constant_expression(right)) {
8204                                 const_expr = right;
8205                                 other_expr = left;
8206                         }
8207
8208                         if (const_expr != NULL) {
8209                                 type_t *other_type = skip_typeref(other_expr->base.type);
8210                                 long    val        = fold_constant(const_expr);
8211                                 /* TODO: check if val can be represented by other_type */
8212                                 (void) other_type;
8213                                 (void) val;
8214                         }
8215                         warningf(&expression->base.source_position,
8216                                  "comparison between signed and unsigned");
8217                 }
8218                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8219                 expression->left        = create_implicit_cast(left, arithmetic_type);
8220                 expression->right       = create_implicit_cast(right, arithmetic_type);
8221                 expression->base.type   = arithmetic_type;
8222                 if (warning.float_equal &&
8223                     (expression->base.kind == EXPR_BINARY_EQUAL ||
8224                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
8225                     is_type_float(arithmetic_type)) {
8226                         warningf(&expression->base.source_position,
8227                                  "comparing floating point with == or != is unsafe");
8228                 }
8229         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8230                 /* TODO check compatibility */
8231         } else if (is_type_pointer(type_left)) {
8232                 expression->right = create_implicit_cast(right, type_left);
8233         } else if (is_type_pointer(type_right)) {
8234                 expression->left = create_implicit_cast(left, type_right);
8235         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8236                 type_error_incompatible("invalid operands in comparison",
8237                                         &expression->base.source_position,
8238                                         type_left, type_right);
8239         }
8240         expression->base.type = type_int;
8241 }
8242
8243 /**
8244  * Checks if a compound type has constant fields.
8245  */
8246 static bool has_const_fields(const compound_type_t *type)
8247 {
8248         const scope_t       *scope       = &type->declaration->scope;
8249         const declaration_t *declaration = scope->declarations;
8250
8251         for (; declaration != NULL; declaration = declaration->next) {
8252                 if (declaration->namespc != NAMESPACE_NORMAL)
8253                         continue;
8254
8255                 const type_t *decl_type = skip_typeref(declaration->type);
8256                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
8257                         return true;
8258         }
8259         /* TODO */
8260         return false;
8261 }
8262
8263 static bool is_valid_assignment_lhs(expression_t const* const left)
8264 {
8265         type_t *const orig_type_left = revert_automatic_type_conversion(left);
8266         type_t *const type_left      = skip_typeref(orig_type_left);
8267
8268         if (!is_lvalue(left)) {
8269                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
8270                        left);
8271                 return false;
8272         }
8273
8274         if (is_type_array(type_left)) {
8275                 errorf(HERE, "cannot assign to arrays ('%E')", left);
8276                 return false;
8277         }
8278         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
8279                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
8280                        orig_type_left);
8281                 return false;
8282         }
8283         if (is_type_incomplete(type_left)) {
8284                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
8285                        left, orig_type_left);
8286                 return false;
8287         }
8288         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
8289                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
8290                        left, orig_type_left);
8291                 return false;
8292         }
8293
8294         return true;
8295 }
8296
8297 static void semantic_arithmetic_assign(binary_expression_t *expression)
8298 {
8299         expression_t *left            = expression->left;
8300         expression_t *right           = expression->right;
8301         type_t       *orig_type_left  = left->base.type;
8302         type_t       *orig_type_right = right->base.type;
8303
8304         if (!is_valid_assignment_lhs(left))
8305                 return;
8306
8307         type_t *type_left  = skip_typeref(orig_type_left);
8308         type_t *type_right = skip_typeref(orig_type_right);
8309
8310         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8311                 /* TODO: improve error message */
8312                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8313                         errorf(&expression->base.source_position,
8314                                "operation needs arithmetic types");
8315                 }
8316                 return;
8317         }
8318
8319         /* combined instructions are tricky. We can't create an implicit cast on
8320          * the left side, because we need the uncasted form for the store.
8321          * The ast2firm pass has to know that left_type must be right_type
8322          * for the arithmetic operation and create a cast by itself */
8323         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8324         expression->right       = create_implicit_cast(right, arithmetic_type);
8325         expression->base.type   = type_left;
8326 }
8327
8328 static void semantic_divmod_assign(binary_expression_t *expression)
8329 {
8330         semantic_arithmetic_assign(expression);
8331         warn_div_by_zero(expression);
8332 }
8333
8334 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
8335 {
8336         expression_t *const left            = expression->left;
8337         expression_t *const right           = expression->right;
8338         type_t       *const orig_type_left  = left->base.type;
8339         type_t       *const orig_type_right = right->base.type;
8340         type_t       *const type_left       = skip_typeref(orig_type_left);
8341         type_t       *const type_right      = skip_typeref(orig_type_right);
8342
8343         if (!is_valid_assignment_lhs(left))
8344                 return;
8345
8346         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8347                 /* combined instructions are tricky. We can't create an implicit cast on
8348                  * the left side, because we need the uncasted form for the store.
8349                  * The ast2firm pass has to know that left_type must be right_type
8350                  * for the arithmetic operation and create a cast by itself */
8351                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
8352                 expression->right     = create_implicit_cast(right, arithmetic_type);
8353                 expression->base.type = type_left;
8354         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8355                 check_pointer_arithmetic(&expression->base.source_position,
8356                                          type_left, orig_type_left);
8357                 expression->base.type = type_left;
8358         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8359                 errorf(&expression->base.source_position,
8360                        "incompatible types '%T' and '%T' in assignment",
8361                        orig_type_left, orig_type_right);
8362         }
8363 }
8364
8365 /**
8366  * Check the semantic restrictions of a logical expression.
8367  */
8368 static void semantic_logical_op(binary_expression_t *expression)
8369 {
8370         expression_t *const left            = expression->left;
8371         expression_t *const right           = expression->right;
8372         type_t       *const orig_type_left  = left->base.type;
8373         type_t       *const orig_type_right = right->base.type;
8374         type_t       *const type_left       = skip_typeref(orig_type_left);
8375         type_t       *const type_right      = skip_typeref(orig_type_right);
8376
8377         warn_function_address_as_bool(left);
8378         warn_function_address_as_bool(right);
8379
8380         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
8381                 /* TODO: improve error message */
8382                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8383                         errorf(&expression->base.source_position,
8384                                "operation needs scalar types");
8385                 }
8386                 return;
8387         }
8388
8389         expression->base.type = type_int;
8390 }
8391
8392 /**
8393  * Check the semantic restrictions of a binary assign expression.
8394  */
8395 static void semantic_binexpr_assign(binary_expression_t *expression)
8396 {
8397         expression_t *left           = expression->left;
8398         type_t       *orig_type_left = left->base.type;
8399
8400         if (!is_valid_assignment_lhs(left))
8401                 return;
8402
8403         assign_error_t error = semantic_assign(orig_type_left, expression->right);
8404         report_assign_error(error, orig_type_left, expression->right,
8405                         "assignment", &left->base.source_position);
8406         expression->right = create_implicit_cast(expression->right, orig_type_left);
8407         expression->base.type = orig_type_left;
8408 }
8409
8410 /**
8411  * Determine if the outermost operation (or parts thereof) of the given
8412  * expression has no effect in order to generate a warning about this fact.
8413  * Therefore in some cases this only examines some of the operands of the
8414  * expression (see comments in the function and examples below).
8415  * Examples:
8416  *   f() + 23;    // warning, because + has no effect
8417  *   x || f();    // no warning, because x controls execution of f()
8418  *   x ? y : f(); // warning, because y has no effect
8419  *   (void)x;     // no warning to be able to suppress the warning
8420  * This function can NOT be used for an "expression has definitely no effect"-
8421  * analysis. */
8422 static bool expression_has_effect(const expression_t *const expr)
8423 {
8424         switch (expr->kind) {
8425                 case EXPR_UNKNOWN:                   break;
8426                 case EXPR_INVALID:                   return true; /* do NOT warn */
8427                 case EXPR_REFERENCE:                 return false;
8428                 /* suppress the warning for microsoft __noop operations */
8429                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
8430                 case EXPR_CHARACTER_CONSTANT:        return false;
8431                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
8432                 case EXPR_STRING_LITERAL:            return false;
8433                 case EXPR_WIDE_STRING_LITERAL:       return false;
8434                 case EXPR_LABEL_ADDRESS:             return false;
8435
8436                 case EXPR_CALL: {
8437                         const call_expression_t *const call = &expr->call;
8438                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
8439                                 return true;
8440
8441                         switch (call->function->builtin_symbol.symbol->ID) {
8442                                 case T___builtin_va_end: return true;
8443                                 default:                 return false;
8444                         }
8445                 }
8446
8447                 /* Generate the warning if either the left or right hand side of a
8448                  * conditional expression has no effect */
8449                 case EXPR_CONDITIONAL: {
8450                         const conditional_expression_t *const cond = &expr->conditional;
8451                         return
8452                                 expression_has_effect(cond->true_expression) &&
8453                                 expression_has_effect(cond->false_expression);
8454                 }
8455
8456                 case EXPR_SELECT:                    return false;
8457                 case EXPR_ARRAY_ACCESS:              return false;
8458                 case EXPR_SIZEOF:                    return false;
8459                 case EXPR_CLASSIFY_TYPE:             return false;
8460                 case EXPR_ALIGNOF:                   return false;
8461
8462                 case EXPR_FUNCNAME:                  return false;
8463                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
8464                 case EXPR_BUILTIN_CONSTANT_P:        return false;
8465                 case EXPR_BUILTIN_PREFETCH:          return true;
8466                 case EXPR_OFFSETOF:                  return false;
8467                 case EXPR_VA_START:                  return true;
8468                 case EXPR_VA_ARG:                    return true;
8469                 case EXPR_STATEMENT:                 return true; // TODO
8470                 case EXPR_COMPOUND_LITERAL:          return false;
8471
8472                 case EXPR_UNARY_NEGATE:              return false;
8473                 case EXPR_UNARY_PLUS:                return false;
8474                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
8475                 case EXPR_UNARY_NOT:                 return false;
8476                 case EXPR_UNARY_DEREFERENCE:         return false;
8477                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
8478                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
8479                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
8480                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
8481                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
8482
8483                 /* Treat void casts as if they have an effect in order to being able to
8484                  * suppress the warning */
8485                 case EXPR_UNARY_CAST: {
8486                         type_t *const type = skip_typeref(expr->base.type);
8487                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
8488                 }
8489
8490                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
8491                 case EXPR_UNARY_ASSUME:              return true;
8492
8493                 case EXPR_BINARY_ADD:                return false;
8494                 case EXPR_BINARY_SUB:                return false;
8495                 case EXPR_BINARY_MUL:                return false;
8496                 case EXPR_BINARY_DIV:                return false;
8497                 case EXPR_BINARY_MOD:                return false;
8498                 case EXPR_BINARY_EQUAL:              return false;
8499                 case EXPR_BINARY_NOTEQUAL:           return false;
8500                 case EXPR_BINARY_LESS:               return false;
8501                 case EXPR_BINARY_LESSEQUAL:          return false;
8502                 case EXPR_BINARY_GREATER:            return false;
8503                 case EXPR_BINARY_GREATEREQUAL:       return false;
8504                 case EXPR_BINARY_BITWISE_AND:        return false;
8505                 case EXPR_BINARY_BITWISE_OR:         return false;
8506                 case EXPR_BINARY_BITWISE_XOR:        return false;
8507                 case EXPR_BINARY_SHIFTLEFT:          return false;
8508                 case EXPR_BINARY_SHIFTRIGHT:         return false;
8509                 case EXPR_BINARY_ASSIGN:             return true;
8510                 case EXPR_BINARY_MUL_ASSIGN:         return true;
8511                 case EXPR_BINARY_DIV_ASSIGN:         return true;
8512                 case EXPR_BINARY_MOD_ASSIGN:         return true;
8513                 case EXPR_BINARY_ADD_ASSIGN:         return true;
8514                 case EXPR_BINARY_SUB_ASSIGN:         return true;
8515                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
8516                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
8517                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
8518                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
8519                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
8520
8521                 /* Only examine the right hand side of && and ||, because the left hand
8522                  * side already has the effect of controlling the execution of the right
8523                  * hand side */
8524                 case EXPR_BINARY_LOGICAL_AND:
8525                 case EXPR_BINARY_LOGICAL_OR:
8526                 /* Only examine the right hand side of a comma expression, because the left
8527                  * hand side has a separate warning */
8528                 case EXPR_BINARY_COMMA:
8529                         return expression_has_effect(expr->binary.right);
8530
8531                 case EXPR_BINARY_BUILTIN_EXPECT:     return true;
8532                 case EXPR_BINARY_ISGREATER:          return false;
8533                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
8534                 case EXPR_BINARY_ISLESS:             return false;
8535                 case EXPR_BINARY_ISLESSEQUAL:        return false;
8536                 case EXPR_BINARY_ISLESSGREATER:      return false;
8537                 case EXPR_BINARY_ISUNORDERED:        return false;
8538         }
8539
8540         internal_errorf(HERE, "unexpected expression");
8541 }
8542
8543 static void semantic_comma(binary_expression_t *expression)
8544 {
8545         if (warning.unused_value) {
8546                 const expression_t *const left = expression->left;
8547                 if (!expression_has_effect(left)) {
8548                         warningf(&left->base.source_position,
8549                                  "left-hand operand of comma expression has no effect");
8550                 }
8551         }
8552         expression->base.type = expression->right->base.type;
8553 }
8554
8555 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr)  \
8556 static expression_t *parse_##binexpression_type(unsigned precedence,      \
8557                                                 expression_t *left)       \
8558 {                                                                         \
8559         expression_t *binexpr = allocate_expression_zero(binexpression_type); \
8560         binexpr->base.source_position = *HERE;                                \
8561         binexpr->binary.left          = left;                                 \
8562         eat(token_type);                                                      \
8563                                                                           \
8564         expression_t *right = parse_sub_expression(precedence + lr);          \
8565                                                                           \
8566         binexpr->binary.right = right;                                        \
8567         sfunc(&binexpr->binary);                                              \
8568                                                                           \
8569         return binexpr;                                                       \
8570 }
8571
8572 CREATE_BINEXPR_PARSER(',', EXPR_BINARY_COMMA,    semantic_comma, 1)
8573 CREATE_BINEXPR_PARSER('*', EXPR_BINARY_MUL,      semantic_binexpr_arithmetic, 1)
8574 CREATE_BINEXPR_PARSER('/', EXPR_BINARY_DIV,      semantic_divmod_arithmetic, 1)
8575 CREATE_BINEXPR_PARSER('%', EXPR_BINARY_MOD,      semantic_divmod_arithmetic, 1)
8576 CREATE_BINEXPR_PARSER('+', EXPR_BINARY_ADD,      semantic_add, 1)
8577 CREATE_BINEXPR_PARSER('-', EXPR_BINARY_SUB,      semantic_sub, 1)
8578 CREATE_BINEXPR_PARSER('<', EXPR_BINARY_LESS,     semantic_comparison, 1)
8579 CREATE_BINEXPR_PARSER('>', EXPR_BINARY_GREATER,  semantic_comparison, 1)
8580 CREATE_BINEXPR_PARSER('=', EXPR_BINARY_ASSIGN,   semantic_binexpr_assign, 0)
8581
8582 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,
8583                       semantic_comparison, 1)
8584 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,
8585                       semantic_comparison, 1)
8586 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,
8587                       semantic_comparison, 1)
8588 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,
8589                       semantic_comparison, 1)
8590
8591 CREATE_BINEXPR_PARSER('&', EXPR_BINARY_BITWISE_AND,
8592                       semantic_binexpr_arithmetic, 1)
8593 CREATE_BINEXPR_PARSER('|', EXPR_BINARY_BITWISE_OR,
8594                       semantic_binexpr_arithmetic, 1)
8595 CREATE_BINEXPR_PARSER('^', EXPR_BINARY_BITWISE_XOR,
8596                       semantic_binexpr_arithmetic, 1)
8597 CREATE_BINEXPR_PARSER(T_ANDAND, EXPR_BINARY_LOGICAL_AND,
8598                       semantic_logical_op, 1)
8599 CREATE_BINEXPR_PARSER(T_PIPEPIPE, EXPR_BINARY_LOGICAL_OR,
8600                       semantic_logical_op, 1)
8601 CREATE_BINEXPR_PARSER(T_LESSLESS, EXPR_BINARY_SHIFTLEFT,
8602                       semantic_shift_op, 1)
8603 CREATE_BINEXPR_PARSER(T_GREATERGREATER, EXPR_BINARY_SHIFTRIGHT,
8604                       semantic_shift_op, 1)
8605 CREATE_BINEXPR_PARSER(T_PLUSEQUAL, EXPR_BINARY_ADD_ASSIGN,
8606                       semantic_arithmetic_addsubb_assign, 0)
8607 CREATE_BINEXPR_PARSER(T_MINUSEQUAL, EXPR_BINARY_SUB_ASSIGN,
8608                       semantic_arithmetic_addsubb_assign, 0)
8609 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, EXPR_BINARY_MUL_ASSIGN,
8610                       semantic_arithmetic_assign, 0)
8611 CREATE_BINEXPR_PARSER(T_SLASHEQUAL, EXPR_BINARY_DIV_ASSIGN,
8612                       semantic_divmod_assign, 0)
8613 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, EXPR_BINARY_MOD_ASSIGN,
8614                       semantic_divmod_assign, 0)
8615 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, EXPR_BINARY_SHIFTLEFT_ASSIGN,
8616                       semantic_arithmetic_assign, 0)
8617 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, EXPR_BINARY_SHIFTRIGHT_ASSIGN,
8618                       semantic_arithmetic_assign, 0)
8619 CREATE_BINEXPR_PARSER(T_ANDEQUAL, EXPR_BINARY_BITWISE_AND_ASSIGN,
8620                       semantic_arithmetic_assign, 0)
8621 CREATE_BINEXPR_PARSER(T_PIPEEQUAL, EXPR_BINARY_BITWISE_OR_ASSIGN,
8622                       semantic_arithmetic_assign, 0)
8623 CREATE_BINEXPR_PARSER(T_CARETEQUAL, EXPR_BINARY_BITWISE_XOR_ASSIGN,
8624                       semantic_arithmetic_assign, 0)
8625
8626 static expression_t *parse_sub_expression(unsigned precedence)
8627 {
8628         if (token.type < 0) {
8629                 return expected_expression_error();
8630         }
8631
8632         expression_parser_function_t *parser
8633                 = &expression_parsers[token.type];
8634         source_position_t             source_position = token.source_position;
8635         expression_t                 *left;
8636
8637         if (parser->parser != NULL) {
8638                 left = parser->parser(parser->precedence);
8639         } else {
8640                 left = parse_primary_expression();
8641         }
8642         assert(left != NULL);
8643         left->base.source_position = source_position;
8644
8645         while(true) {
8646                 if (token.type < 0) {
8647                         return expected_expression_error();
8648                 }
8649
8650                 parser = &expression_parsers[token.type];
8651                 if (parser->infix_parser == NULL)
8652                         break;
8653                 if (parser->infix_precedence < precedence)
8654                         break;
8655
8656                 left = parser->infix_parser(parser->infix_precedence, left);
8657
8658                 assert(left != NULL);
8659                 assert(left->kind != EXPR_UNKNOWN);
8660                 left->base.source_position = source_position;
8661         }
8662
8663         return left;
8664 }
8665
8666 /**
8667  * Parse an expression.
8668  */
8669 static expression_t *parse_expression(void)
8670 {
8671         return parse_sub_expression(1);
8672 }
8673
8674 /**
8675  * Register a parser for a prefix-like operator with given precedence.
8676  *
8677  * @param parser      the parser function
8678  * @param token_type  the token type of the prefix token
8679  * @param precedence  the precedence of the operator
8680  */
8681 static void register_expression_parser(parse_expression_function parser,
8682                                        int token_type, unsigned precedence)
8683 {
8684         expression_parser_function_t *entry = &expression_parsers[token_type];
8685
8686         if (entry->parser != NULL) {
8687                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8688                 panic("trying to register multiple expression parsers for a token");
8689         }
8690         entry->parser     = parser;
8691         entry->precedence = precedence;
8692 }
8693
8694 /**
8695  * Register a parser for an infix operator with given precedence.
8696  *
8697  * @param parser      the parser function
8698  * @param token_type  the token type of the infix operator
8699  * @param precedence  the precedence of the operator
8700  */
8701 static void register_infix_parser(parse_expression_infix_function parser,
8702                 int token_type, unsigned precedence)
8703 {
8704         expression_parser_function_t *entry = &expression_parsers[token_type];
8705
8706         if (entry->infix_parser != NULL) {
8707                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8708                 panic("trying to register multiple infix expression parsers for a "
8709                       "token");
8710         }
8711         entry->infix_parser     = parser;
8712         entry->infix_precedence = precedence;
8713 }
8714
8715 /**
8716  * Initialize the expression parsers.
8717  */
8718 static void init_expression_parsers(void)
8719 {
8720         memset(&expression_parsers, 0, sizeof(expression_parsers));
8721
8722         register_infix_parser(parse_array_expression,         '[',              30);
8723         register_infix_parser(parse_call_expression,          '(',              30);
8724         register_infix_parser(parse_select_expression,        '.',              30);
8725         register_infix_parser(parse_select_expression,        T_MINUSGREATER,   30);
8726         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,
8727                                                               T_PLUSPLUS,       30);
8728         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,
8729                                                               T_MINUSMINUS,     30);
8730
8731         register_infix_parser(parse_EXPR_BINARY_MUL,          '*',              17);
8732         register_infix_parser(parse_EXPR_BINARY_DIV,          '/',              17);
8733         register_infix_parser(parse_EXPR_BINARY_MOD,          '%',              17);
8734         register_infix_parser(parse_EXPR_BINARY_ADD,          '+',              16);
8735         register_infix_parser(parse_EXPR_BINARY_SUB,          '-',              16);
8736         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,    T_LESSLESS,       15);
8737         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,   T_GREATERGREATER, 15);
8738         register_infix_parser(parse_EXPR_BINARY_LESS,         '<',              14);
8739         register_infix_parser(parse_EXPR_BINARY_GREATER,      '>',              14);
8740         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,    T_LESSEQUAL,      14);
8741         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL, T_GREATEREQUAL,   14);
8742         register_infix_parser(parse_EXPR_BINARY_EQUAL,        T_EQUALEQUAL,     13);
8743         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,
8744                                                     T_EXCLAMATIONMARKEQUAL, 13);
8745         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,  '&',              12);
8746         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,  '^',              11);
8747         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,   '|',              10);
8748         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,  T_ANDAND,          9);
8749         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,   T_PIPEPIPE,        8);
8750         register_infix_parser(parse_conditional_expression,   '?',               7);
8751         register_infix_parser(parse_EXPR_BINARY_ASSIGN,       '=',               2);
8752         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,   T_PLUSEQUAL,       2);
8753         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,   T_MINUSEQUAL,      2);
8754         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,   T_ASTERISKEQUAL,   2);
8755         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,   T_SLASHEQUAL,      2);
8756         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,   T_PERCENTEQUAL,    2);
8757         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,
8758                                                                 T_LESSLESSEQUAL, 2);
8759         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,
8760                                                           T_GREATERGREATEREQUAL, 2);
8761         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN,
8762                                                                      T_ANDEQUAL, 2);
8763         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,
8764                                                                     T_PIPEEQUAL, 2);
8765         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN,
8766                                                                    T_CARETEQUAL, 2);
8767
8768         register_infix_parser(parse_EXPR_BINARY_COMMA,        ',',               1);
8769
8770         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-',      25);
8771         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+',      25);
8772         register_expression_parser(parse_EXPR_UNARY_NOT,              '!',      25);
8773         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~',      25);
8774         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*',      25);
8775         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&',      25);
8776         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT,
8777                                                                   T_PLUSPLUS,   25);
8778         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT,
8779                                                                   T_MINUSMINUS, 25);
8780         register_expression_parser(parse_sizeof,                      T_sizeof, 25);
8781         register_expression_parser(parse_alignof,                T___alignof__, 25);
8782         register_expression_parser(parse_extension,            T___extension__, 25);
8783         register_expression_parser(parse_builtin_classify_type,
8784                                                      T___builtin_classify_type, 25);
8785 }
8786
8787 /**
8788  * Parse a asm statement arguments specification.
8789  */
8790 static asm_argument_t *parse_asm_arguments(bool is_out)
8791 {
8792         asm_argument_t *result = NULL;
8793         asm_argument_t *last   = NULL;
8794
8795         while (token.type == T_STRING_LITERAL || token.type == '[') {
8796                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8797                 memset(argument, 0, sizeof(argument[0]));
8798
8799                 if (token.type == '[') {
8800                         eat('[');
8801                         if (token.type != T_IDENTIFIER) {
8802                                 parse_error_expected("while parsing asm argument",
8803                                                      T_IDENTIFIER, NULL);
8804                                 return NULL;
8805                         }
8806                         argument->symbol = token.v.symbol;
8807
8808                         expect(']');
8809                 }
8810
8811                 argument->constraints = parse_string_literals();
8812                 expect('(');
8813                 add_anchor_token(')');
8814                 expression_t *expression = parse_expression();
8815                 rem_anchor_token(')');
8816                 if (is_out) {
8817                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
8818                          * change size or type representation (e.g. int -> long is ok, but
8819                          * int -> float is not) */
8820                         if (expression->kind == EXPR_UNARY_CAST) {
8821                                 type_t      *const type = expression->base.type;
8822                                 type_kind_t  const kind = type->kind;
8823                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
8824                                         unsigned flags;
8825                                         unsigned size;
8826                                         if (kind == TYPE_ATOMIC) {
8827                                                 atomic_type_kind_t const akind = type->atomic.akind;
8828                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8829                                                 size  = get_atomic_type_size(akind);
8830                                         } else {
8831                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8832                                                 size  = get_atomic_type_size(get_intptr_kind());
8833                                         }
8834
8835                                         do {
8836                                                 expression_t *const value      = expression->unary.value;
8837                                                 type_t       *const value_type = value->base.type;
8838                                                 type_kind_t   const value_kind = value_type->kind;
8839
8840                                                 unsigned value_flags;
8841                                                 unsigned value_size;
8842                                                 if (value_kind == TYPE_ATOMIC) {
8843                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
8844                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8845                                                         value_size  = get_atomic_type_size(value_akind);
8846                                                 } else if (value_kind == TYPE_POINTER) {
8847                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8848                                                         value_size  = get_atomic_type_size(get_intptr_kind());
8849                                                 } else {
8850                                                         break;
8851                                                 }
8852
8853                                                 if (value_flags != flags || value_size != size)
8854                                                         break;
8855
8856                                                 expression = value;
8857                                         } while (expression->kind == EXPR_UNARY_CAST);
8858                                 }
8859                         }
8860
8861                         if (!is_lvalue(expression)) {
8862                                 errorf(&expression->base.source_position,
8863                                        "asm output argument is not an lvalue");
8864                         }
8865
8866                         if (argument->constraints.begin[0] == '+')
8867                                 mark_decls_read(expression, NULL);
8868                 } else {
8869                         mark_decls_read(expression, NULL);
8870                 }
8871                 argument->expression = expression;
8872                 expect(')');
8873
8874                 set_address_taken(expression, true);
8875
8876                 if (last != NULL) {
8877                         last->next = argument;
8878                 } else {
8879                         result = argument;
8880                 }
8881                 last = argument;
8882
8883                 if (token.type != ',')
8884                         break;
8885                 eat(',');
8886         }
8887
8888         return result;
8889 end_error:
8890         return NULL;
8891 }
8892
8893 /**
8894  * Parse a asm statement clobber specification.
8895  */
8896 static asm_clobber_t *parse_asm_clobbers(void)
8897 {
8898         asm_clobber_t *result = NULL;
8899         asm_clobber_t *last   = NULL;
8900
8901         while(token.type == T_STRING_LITERAL) {
8902                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
8903                 clobber->clobber       = parse_string_literals();
8904
8905                 if (last != NULL) {
8906                         last->next = clobber;
8907                 } else {
8908                         result = clobber;
8909                 }
8910                 last = clobber;
8911
8912                 if (token.type != ',')
8913                         break;
8914                 eat(',');
8915         }
8916
8917         return result;
8918 }
8919
8920 /**
8921  * Parse an asm statement.
8922  */
8923 static statement_t *parse_asm_statement(void)
8924 {
8925         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
8926         asm_statement_t *asm_statement = &statement->asms;
8927
8928         eat(T_asm);
8929
8930         if (token.type == T_volatile) {
8931                 next_token();
8932                 asm_statement->is_volatile = true;
8933         }
8934
8935         expect('(');
8936         add_anchor_token(')');
8937         add_anchor_token(':');
8938         asm_statement->asm_text = parse_string_literals();
8939
8940         if (token.type != ':') {
8941                 rem_anchor_token(':');
8942                 goto end_of_asm;
8943         }
8944         eat(':');
8945
8946         asm_statement->outputs = parse_asm_arguments(true);
8947         if (token.type != ':') {
8948                 rem_anchor_token(':');
8949                 goto end_of_asm;
8950         }
8951         eat(':');
8952
8953         asm_statement->inputs = parse_asm_arguments(false);
8954         if (token.type != ':') {
8955                 rem_anchor_token(':');
8956                 goto end_of_asm;
8957         }
8958         rem_anchor_token(':');
8959         eat(':');
8960
8961         asm_statement->clobbers = parse_asm_clobbers();
8962
8963 end_of_asm:
8964         rem_anchor_token(')');
8965         expect(')');
8966         expect(';');
8967
8968         if (asm_statement->outputs == NULL) {
8969                 /* GCC: An 'asm' instruction without any output operands will be treated
8970                  * identically to a volatile 'asm' instruction. */
8971                 asm_statement->is_volatile = true;
8972         }
8973
8974         return statement;
8975 end_error:
8976         return create_invalid_statement();
8977 }
8978
8979 /**
8980  * Parse a case statement.
8981  */
8982 static statement_t *parse_case_statement(void)
8983 {
8984         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8985         source_position_t *const pos       = &statement->base.source_position;
8986
8987         eat(T_case);
8988
8989         expression_t *const expression   = parse_expression();
8990         statement->case_label.expression = expression;
8991         if (!is_constant_expression(expression)) {
8992                 /* This check does not prevent the error message in all cases of an
8993                  * prior error while parsing the expression.  At least it catches the
8994                  * common case of a mistyped enum entry. */
8995                 if (is_type_valid(skip_typeref(expression->base.type))) {
8996                         errorf(pos, "case label does not reduce to an integer constant");
8997                 }
8998                 statement->case_label.is_bad = true;
8999         } else {
9000                 long const val = fold_constant(expression);
9001                 statement->case_label.first_case = val;
9002                 statement->case_label.last_case  = val;
9003         }
9004
9005         if (GNU_MODE) {
9006                 if (token.type == T_DOTDOTDOT) {
9007                         next_token();
9008                         expression_t *const end_range   = parse_expression();
9009                         statement->case_label.end_range = end_range;
9010                         if (!is_constant_expression(end_range)) {
9011                                 /* This check does not prevent the error message in all cases of an
9012                                  * prior error while parsing the expression.  At least it catches the
9013                                  * common case of a mistyped enum entry. */
9014                                 if (is_type_valid(skip_typeref(end_range->base.type))) {
9015                                         errorf(pos, "case range does not reduce to an integer constant");
9016                                 }
9017                                 statement->case_label.is_bad = true;
9018                         } else {
9019                                 long const val = fold_constant(end_range);
9020                                 statement->case_label.last_case = val;
9021
9022                                 if (val < statement->case_label.first_case) {
9023                                         statement->case_label.is_empty_range = true;
9024                                         warningf(pos, "empty range specified");
9025                                 }
9026                         }
9027                 }
9028         }
9029
9030         PUSH_PARENT(statement);
9031
9032         expect(':');
9033
9034         if (current_switch != NULL) {
9035                 if (! statement->case_label.is_bad) {
9036                         /* Check for duplicate case values */
9037                         case_label_statement_t *c = &statement->case_label;
9038                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9039                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9040                                         continue;
9041
9042                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9043                                         continue;
9044
9045                                 errorf(pos, "duplicate case value (previously used %P)",
9046                                        &l->base.source_position);
9047                                 break;
9048                         }
9049                 }
9050                 /* link all cases into the switch statement */
9051                 if (current_switch->last_case == NULL) {
9052                         current_switch->first_case      = &statement->case_label;
9053                 } else {
9054                         current_switch->last_case->next = &statement->case_label;
9055                 }
9056                 current_switch->last_case = &statement->case_label;
9057         } else {
9058                 errorf(pos, "case label not within a switch statement");
9059         }
9060
9061         statement_t *const inner_stmt = parse_statement();
9062         statement->case_label.statement = inner_stmt;
9063         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9064                 errorf(&inner_stmt->base.source_position, "declaration after case label");
9065         }
9066
9067         POP_PARENT;
9068         return statement;
9069 end_error:
9070         POP_PARENT;
9071         return create_invalid_statement();
9072 }
9073
9074 /**
9075  * Parse a default statement.
9076  */
9077 static statement_t *parse_default_statement(void)
9078 {
9079         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9080
9081         eat(T_default);
9082
9083         PUSH_PARENT(statement);
9084
9085         expect(':');
9086         if (current_switch != NULL) {
9087                 const case_label_statement_t *def_label = current_switch->default_label;
9088                 if (def_label != NULL) {
9089                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9090                                &def_label->base.source_position);
9091                 } else {
9092                         current_switch->default_label = &statement->case_label;
9093
9094                         /* link all cases into the switch statement */
9095                         if (current_switch->last_case == NULL) {
9096                                 current_switch->first_case      = &statement->case_label;
9097                         } else {
9098                                 current_switch->last_case->next = &statement->case_label;
9099                         }
9100                         current_switch->last_case = &statement->case_label;
9101                 }
9102         } else {
9103                 errorf(&statement->base.source_position,
9104                         "'default' label not within a switch statement");
9105         }
9106
9107         statement_t *const inner_stmt = parse_statement();
9108         statement->case_label.statement = inner_stmt;
9109         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9110                 errorf(&inner_stmt->base.source_position, "declaration after default label");
9111         }
9112
9113         POP_PARENT;
9114         return statement;
9115 end_error:
9116         POP_PARENT;
9117         return create_invalid_statement();
9118 }
9119
9120 /**
9121  * Parse a label statement.
9122  */
9123 static statement_t *parse_label_statement(void)
9124 {
9125         assert(token.type == T_IDENTIFIER);
9126         symbol_t      *symbol = token.v.symbol;
9127         declaration_t *label  = get_label(symbol);
9128
9129         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9130         statement->label.label       = label;
9131
9132         next_token();
9133
9134         PUSH_PARENT(statement);
9135
9136         /* if statement is already set then the label is defined twice,
9137          * otherwise it was just mentioned in a goto/local label declaration so far */
9138         if (label->init.statement != NULL) {
9139                 errorf(HERE, "duplicate label '%Y' (declared %P)",
9140                        symbol, &label->source_position);
9141         } else {
9142                 label->source_position = token.source_position;
9143                 label->init.statement  = statement;
9144         }
9145
9146         eat(':');
9147
9148         if (token.type == '}') {
9149                 /* TODO only warn? */
9150                 if (false) {
9151                         warningf(HERE, "label at end of compound statement");
9152                         statement->label.statement = create_empty_statement();
9153                 } else {
9154                         errorf(HERE, "label at end of compound statement");
9155                         statement->label.statement = create_invalid_statement();
9156                 }
9157         } else if (token.type == ';') {
9158                 /* Eat an empty statement here, to avoid the warning about an empty
9159                  * statement after a label.  label:; is commonly used to have a label
9160                  * before a closing brace. */
9161                 statement->label.statement = create_empty_statement();
9162                 next_token();
9163         } else {
9164                 statement_t *const inner_stmt = parse_statement();
9165                 statement->label.statement = inner_stmt;
9166                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
9167                         errorf(&inner_stmt->base.source_position, "declaration after label");
9168                 }
9169         }
9170
9171         /* remember the labels in a list for later checking */
9172         if (label_last == NULL) {
9173                 label_first = &statement->label;
9174         } else {
9175                 label_last->next = &statement->label;
9176         }
9177         label_last = &statement->label;
9178
9179         POP_PARENT;
9180         return statement;
9181 }
9182
9183 /**
9184  * Parse an if statement.
9185  */
9186 static statement_t *parse_if(void)
9187 {
9188         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
9189
9190         eat(T_if);
9191
9192         PUSH_PARENT(statement);
9193
9194         add_anchor_token('{');
9195
9196         expect('(');
9197         add_anchor_token(')');
9198         expression_t *const expr = parse_expression();
9199         statement->ifs.condition = expr;
9200         mark_decls_read(expr, NULL);
9201         rem_anchor_token(')');
9202         expect(')');
9203
9204 end_error:
9205         rem_anchor_token('{');
9206
9207         add_anchor_token(T_else);
9208         statement->ifs.true_statement = parse_statement();
9209         rem_anchor_token(T_else);
9210
9211         if (token.type == T_else) {
9212                 next_token();
9213                 statement->ifs.false_statement = parse_statement();
9214         }
9215
9216         POP_PARENT;
9217         return statement;
9218 }
9219
9220 /**
9221  * Check that all enums are handled in a switch.
9222  *
9223  * @param statement  the switch statement to check
9224  */
9225 static void check_enum_cases(const switch_statement_t *statement) {
9226         const type_t *type = skip_typeref(statement->expression->base.type);
9227         if (! is_type_enum(type))
9228                 return;
9229         const enum_type_t *enumt = &type->enumt;
9230
9231         /* if we have a default, no warnings */
9232         if (statement->default_label != NULL)
9233                 return;
9234
9235         /* FIXME: calculation of value should be done while parsing */
9236         const declaration_t *declaration;
9237         long last_value = -1;
9238         for (declaration = enumt->declaration->next;
9239              declaration != NULL && declaration->storage_class == STORAGE_CLASS_ENUM_ENTRY;
9240                  declaration = declaration->next) {
9241                 const expression_t *expression = declaration->init.enum_value;
9242                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
9243                 bool                found      = false;
9244                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
9245                         if (l->expression == NULL)
9246                                 continue;
9247                         if (l->first_case <= value && value <= l->last_case) {
9248                                 found = true;
9249                                 break;
9250                         }
9251                 }
9252                 if (! found) {
9253                         warningf(&statement->base.source_position,
9254                                 "enumeration value '%Y' not handled in switch", declaration->symbol);
9255                 }
9256                 last_value = value;
9257         }
9258 }
9259
9260 /**
9261  * Parse a switch statement.
9262  */
9263 static statement_t *parse_switch(void)
9264 {
9265         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
9266
9267         eat(T_switch);
9268
9269         PUSH_PARENT(statement);
9270
9271         expect('(');
9272         add_anchor_token(')');
9273         expression_t *const expr = parse_expression();
9274         mark_decls_read(expr, NULL);
9275         type_t       *      type = skip_typeref(expr->base.type);
9276         if (is_type_integer(type)) {
9277                 type = promote_integer(type);
9278                 if (warning.traditional) {
9279                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
9280                                 warningf(&expr->base.source_position,
9281                                         "'%T' switch expression not converted to '%T' in ISO C",
9282                                         type, type_int);
9283                         }
9284                 }
9285         } else if (is_type_valid(type)) {
9286                 errorf(&expr->base.source_position,
9287                        "switch quantity is not an integer, but '%T'", type);
9288                 type = type_error_type;
9289         }
9290         statement->switchs.expression = create_implicit_cast(expr, type);
9291         expect(')');
9292         rem_anchor_token(')');
9293
9294         switch_statement_t *rem = current_switch;
9295         current_switch          = &statement->switchs;
9296         statement->switchs.body = parse_statement();
9297         current_switch          = rem;
9298
9299         if (warning.switch_default &&
9300             statement->switchs.default_label == NULL) {
9301                 warningf(&statement->base.source_position, "switch has no default case");
9302         }
9303         if (warning.switch_enum)
9304                 check_enum_cases(&statement->switchs);
9305
9306         POP_PARENT;
9307         return statement;
9308 end_error:
9309         POP_PARENT;
9310         return create_invalid_statement();
9311 }
9312
9313 static statement_t *parse_loop_body(statement_t *const loop)
9314 {
9315         statement_t *const rem = current_loop;
9316         current_loop = loop;
9317
9318         statement_t *const body = parse_statement();
9319
9320         current_loop = rem;
9321         return body;
9322 }
9323
9324 /**
9325  * Parse a while statement.
9326  */
9327 static statement_t *parse_while(void)
9328 {
9329         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
9330
9331         eat(T_while);
9332
9333         PUSH_PARENT(statement);
9334
9335         expect('(');
9336         add_anchor_token(')');
9337         expression_t *const cond = parse_expression();
9338         statement->whiles.condition = cond;
9339         mark_decls_read(cond, NULL);
9340         rem_anchor_token(')');
9341         expect(')');
9342
9343         statement->whiles.body = parse_loop_body(statement);
9344
9345         POP_PARENT;
9346         return statement;
9347 end_error:
9348         POP_PARENT;
9349         return create_invalid_statement();
9350 }
9351
9352 /**
9353  * Parse a do statement.
9354  */
9355 static statement_t *parse_do(void)
9356 {
9357         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
9358
9359         eat(T_do);
9360
9361         PUSH_PARENT(statement);
9362
9363         add_anchor_token(T_while);
9364         statement->do_while.body = parse_loop_body(statement);
9365         rem_anchor_token(T_while);
9366
9367         expect(T_while);
9368         expect('(');
9369         add_anchor_token(')');
9370         expression_t *const cond = parse_expression();
9371         statement->do_while.condition = cond;
9372         mark_decls_read(cond, NULL);
9373         rem_anchor_token(')');
9374         expect(')');
9375         expect(';');
9376
9377         POP_PARENT;
9378         return statement;
9379 end_error:
9380         POP_PARENT;
9381         return create_invalid_statement();
9382 }
9383
9384 /**
9385  * Parse a for statement.
9386  */
9387 static statement_t *parse_for(void)
9388 {
9389         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
9390
9391         eat(T_for);
9392
9393         PUSH_PARENT(statement);
9394
9395         size_t const top = environment_top();
9396         scope_push(&statement->fors.scope);
9397
9398         expect('(');
9399         add_anchor_token(')');
9400
9401         if (token.type != ';') {
9402                 if (is_declaration_specifier(&token, false)) {
9403                         parse_declaration(record_declaration);
9404                 } else {
9405                         add_anchor_token(';');
9406                         expression_t *const init = parse_expression();
9407                         statement->fors.initialisation = init;
9408                         mark_decls_read(init, DECL_ANY);
9409                         if (warning.unused_value && !expression_has_effect(init)) {
9410                                 warningf(&init->base.source_position,
9411                                          "initialisation of 'for'-statement has no effect");
9412                         }
9413                         rem_anchor_token(';');
9414                         expect(';');
9415                 }
9416         } else {
9417                 expect(';');
9418         }
9419
9420         if (token.type != ';') {
9421                 add_anchor_token(';');
9422                 expression_t *const cond = parse_expression();
9423                 statement->fors.condition = cond;
9424                 mark_decls_read(cond, NULL);
9425                 rem_anchor_token(';');
9426         }
9427         expect(';');
9428         if (token.type != ')') {
9429                 expression_t *const step = parse_expression();
9430                 statement->fors.step = step;
9431                 mark_decls_read(step, DECL_ANY);
9432                 if (warning.unused_value && !expression_has_effect(step)) {
9433                         warningf(&step->base.source_position,
9434                                  "step of 'for'-statement has no effect");
9435                 }
9436         }
9437         rem_anchor_token(')');
9438         expect(')');
9439         statement->fors.body = parse_loop_body(statement);
9440
9441         assert(scope == &statement->fors.scope);
9442         scope_pop();
9443         environment_pop_to(top);
9444
9445         POP_PARENT;
9446         return statement;
9447
9448 end_error:
9449         POP_PARENT;
9450         rem_anchor_token(')');
9451         assert(scope == &statement->fors.scope);
9452         scope_pop();
9453         environment_pop_to(top);
9454
9455         return create_invalid_statement();
9456 }
9457
9458 /**
9459  * Parse a goto statement.
9460  */
9461 static statement_t *parse_goto(void)
9462 {
9463         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
9464         eat(T_goto);
9465
9466         if (GNU_MODE && token.type == '*') {
9467                 next_token();
9468                 expression_t *expression = parse_expression();
9469                 mark_decls_read(expression, NULL);
9470
9471                 /* Argh: although documentation say the expression must be of type void *,
9472                  * gcc excepts anything that can be casted into void * without error */
9473                 type_t *type = expression->base.type;
9474
9475                 if (type != type_error_type) {
9476                         if (!is_type_pointer(type) && !is_type_integer(type)) {
9477                                 errorf(&expression->base.source_position,
9478                                         "cannot convert to a pointer type");
9479                         } else if (type != type_void_ptr) {
9480                                 warningf(&expression->base.source_position,
9481                                         "type of computed goto expression should be 'void*' not '%T'", type);
9482                         }
9483                         expression = create_implicit_cast(expression, type_void_ptr);
9484                 }
9485
9486                 statement->gotos.expression = expression;
9487         } else {
9488                 if (token.type != T_IDENTIFIER) {
9489                         if (GNU_MODE)
9490                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
9491                         else
9492                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
9493                         eat_until_anchor();
9494                         goto end_error;
9495                 }
9496                 symbol_t *symbol = token.v.symbol;
9497                 next_token();
9498
9499                 statement->gotos.label = get_label(symbol);
9500
9501                 if (statement->gotos.label->parent_scope->depth < current_function->scope.depth) {
9502                         statement->gotos.outer_fkt_jmp = true;
9503                 }
9504         }
9505
9506         /* remember the goto's in a list for later checking */
9507         if (goto_last == NULL) {
9508                 goto_first = &statement->gotos;
9509         } else {
9510                 goto_last->next = &statement->gotos;
9511         }
9512         goto_last = &statement->gotos;
9513
9514         expect(';');
9515
9516         return statement;
9517 end_error:
9518         return create_invalid_statement();
9519 }
9520
9521 /**
9522  * Parse a continue statement.
9523  */
9524 static statement_t *parse_continue(void)
9525 {
9526         if (current_loop == NULL) {
9527                 errorf(HERE, "continue statement not within loop");
9528         }
9529
9530         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
9531
9532         eat(T_continue);
9533         expect(';');
9534
9535 end_error:
9536         return statement;
9537 }
9538
9539 /**
9540  * Parse a break statement.
9541  */
9542 static statement_t *parse_break(void)
9543 {
9544         if (current_switch == NULL && current_loop == NULL) {
9545                 errorf(HERE, "break statement not within loop or switch");
9546         }
9547
9548         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
9549
9550         eat(T_break);
9551         expect(';');
9552
9553 end_error:
9554         return statement;
9555 }
9556
9557 /**
9558  * Parse a __leave statement.
9559  */
9560 static statement_t *parse_leave_statement(void)
9561 {
9562         if (current_try == NULL) {
9563                 errorf(HERE, "__leave statement not within __try");
9564         }
9565
9566         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
9567
9568         eat(T___leave);
9569         expect(';');
9570
9571 end_error:
9572         return statement;
9573 }
9574
9575 /**
9576  * Check if a given declaration represents a local variable.
9577  */
9578 static bool is_local_var_declaration(const declaration_t *declaration)
9579 {
9580         switch ((storage_class_tag_t) declaration->storage_class) {
9581         case STORAGE_CLASS_AUTO:
9582         case STORAGE_CLASS_REGISTER: {
9583                 const type_t *type = skip_typeref(declaration->type);
9584                 if (is_type_function(type)) {
9585                         return false;
9586                 } else {
9587                         return true;
9588                 }
9589         }
9590         default:
9591                 return false;
9592         }
9593 }
9594
9595 /**
9596  * Check if a given declaration represents a variable.
9597  */
9598 static bool is_var_declaration(const declaration_t *declaration)
9599 {
9600         if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
9601                 return false;
9602
9603         const type_t *type = skip_typeref(declaration->type);
9604         return !is_type_function(type);
9605 }
9606
9607 /**
9608  * Check if a given expression represents a local variable.
9609  */
9610 static bool is_local_variable(const expression_t *expression)
9611 {
9612         if (expression->base.kind != EXPR_REFERENCE) {
9613                 return false;
9614         }
9615         const declaration_t *declaration = expression->reference.declaration;
9616         return is_local_var_declaration(declaration);
9617 }
9618
9619 /**
9620  * Check if a given expression represents a local variable and
9621  * return its declaration then, else return NULL.
9622  */
9623 declaration_t *expr_is_variable(const expression_t *expression)
9624 {
9625         if (expression->base.kind != EXPR_REFERENCE) {
9626                 return NULL;
9627         }
9628         declaration_t *declaration = expression->reference.declaration;
9629         if (is_var_declaration(declaration))
9630                 return declaration;
9631         return NULL;
9632 }
9633
9634 /**
9635  * Parse a return statement.
9636  */
9637 static statement_t *parse_return(void)
9638 {
9639         eat(T_return);
9640
9641         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
9642
9643         expression_t *return_value = NULL;
9644         if (token.type != ';') {
9645                 return_value = parse_expression();
9646                 mark_decls_read(return_value, NULL);
9647         }
9648
9649         const type_t *const func_type = current_function->type;
9650         assert(is_type_function(func_type));
9651         type_t *const return_type = skip_typeref(func_type->function.return_type);
9652
9653         if (return_value != NULL) {
9654                 type_t *return_value_type = skip_typeref(return_value->base.type);
9655
9656                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)
9657                                 && !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
9658                         warningf(&statement->base.source_position,
9659                                  "'return' with a value, in function returning void");
9660                         return_value = NULL;
9661                 } else {
9662                         assign_error_t error = semantic_assign(return_type, return_value);
9663                         report_assign_error(error, return_type, return_value, "'return'",
9664                                             &statement->base.source_position);
9665                         return_value = create_implicit_cast(return_value, return_type);
9666                 }
9667                 /* check for returning address of a local var */
9668                 if (return_value != NULL &&
9669                                 return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
9670                         const expression_t *expression = return_value->unary.value;
9671                         if (is_local_variable(expression)) {
9672                                 warningf(&statement->base.source_position,
9673                                          "function returns address of local variable");
9674                         }
9675                 }
9676         } else {
9677                 if (!is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
9678                         warningf(&statement->base.source_position,
9679                                  "'return' without value, in function returning non-void");
9680                 }
9681         }
9682         statement->returns.value = return_value;
9683
9684         expect(';');
9685
9686 end_error:
9687         return statement;
9688 }
9689
9690 /**
9691  * Parse a declaration statement.
9692  */
9693 static statement_t *parse_declaration_statement(void)
9694 {
9695         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9696
9697         declaration_t *before = last_declaration;
9698         if (GNU_MODE)
9699                 parse_external_declaration();
9700         else
9701                 parse_declaration(record_declaration);
9702
9703         if (before == NULL) {
9704                 statement->declaration.declarations_begin = scope->declarations;
9705         } else {
9706                 statement->declaration.declarations_begin = before->next;
9707         }
9708         statement->declaration.declarations_end = last_declaration;
9709
9710         return statement;
9711 }
9712
9713 /**
9714  * Parse an expression statement, ie. expr ';'.
9715  */
9716 static statement_t *parse_expression_statement(void)
9717 {
9718         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
9719
9720         expression_t *const expr         = parse_expression();
9721         statement->expression.expression = expr;
9722         mark_decls_read(expr, DECL_ANY);
9723
9724         expect(';');
9725
9726 end_error:
9727         return statement;
9728 }
9729
9730 /**
9731  * Parse a microsoft __try { } __finally { } or
9732  * __try{ } __except() { }
9733  */
9734 static statement_t *parse_ms_try_statment(void)
9735 {
9736         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
9737         eat(T___try);
9738
9739         PUSH_PARENT(statement);
9740
9741         ms_try_statement_t *rem = current_try;
9742         current_try = &statement->ms_try;
9743         statement->ms_try.try_statement = parse_compound_statement(false);
9744         current_try = rem;
9745
9746         POP_PARENT;
9747
9748         if (token.type == T___except) {
9749                 eat(T___except);
9750                 expect('(');
9751                 add_anchor_token(')');
9752                 expression_t *const expr = parse_expression();
9753                 mark_decls_read(expr, NULL);
9754                 type_t       *      type = skip_typeref(expr->base.type);
9755                 if (is_type_integer(type)) {
9756                         type = promote_integer(type);
9757                 } else if (is_type_valid(type)) {
9758                         errorf(&expr->base.source_position,
9759                                "__expect expression is not an integer, but '%T'", type);
9760                         type = type_error_type;
9761                 }
9762                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
9763                 rem_anchor_token(')');
9764                 expect(')');
9765                 statement->ms_try.final_statement = parse_compound_statement(false);
9766         } else if (token.type == T__finally) {
9767                 eat(T___finally);
9768                 statement->ms_try.final_statement = parse_compound_statement(false);
9769         } else {
9770                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
9771                 return create_invalid_statement();
9772         }
9773         return statement;
9774 end_error:
9775         return create_invalid_statement();
9776 }
9777
9778 static statement_t *parse_empty_statement(void)
9779 {
9780         if (warning.empty_statement) {
9781                 warningf(HERE, "statement is empty");
9782         }
9783         statement_t *const statement = create_empty_statement();
9784         eat(';');
9785         return statement;
9786 }
9787
9788 static statement_t *parse_local_label_declaration(void) {
9789         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9790
9791         eat(T___label__);
9792
9793         declaration_t *begin = NULL, *end = NULL;
9794
9795         while (true) {
9796                 if (token.type != T_IDENTIFIER) {
9797                         parse_error_expected("while parsing local label declaration",
9798                                 T_IDENTIFIER, NULL);
9799                         goto end_error;
9800                 }
9801                 symbol_t      *symbol      = token.v.symbol;
9802                 declaration_t *declaration = get_declaration(symbol, NAMESPACE_LOCAL_LABEL);
9803                 if (declaration != NULL) {
9804                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition at %P)",
9805                                 symbol, &declaration->source_position);
9806                 } else {
9807                         declaration = allocate_declaration_zero();
9808                         declaration->namespc         = NAMESPACE_LOCAL_LABEL;
9809                         declaration->source_position = token.source_position;
9810                         declaration->symbol          = symbol;
9811                         declaration->parent_scope    = scope;
9812                         declaration->init.statement  = NULL;
9813
9814                         if (end != NULL)
9815                                 end->next = declaration;
9816                         end = declaration;
9817                         if (begin == NULL)
9818                                 begin = declaration;
9819
9820                         local_label_push(declaration);
9821                 }
9822                 next_token();
9823
9824                 if (token.type != ',')
9825                         break;
9826                 next_token();
9827         }
9828         eat(';');
9829 end_error:
9830         statement->declaration.declarations_begin = begin;
9831         statement->declaration.declarations_end   = end;
9832         return statement;
9833 }
9834
9835 /**
9836  * Parse a statement.
9837  * There's also parse_statement() which additionally checks for
9838  * "statement has no effect" warnings
9839  */
9840 static statement_t *intern_parse_statement(void)
9841 {
9842         statement_t *statement = NULL;
9843
9844         /* declaration or statement */
9845         add_anchor_token(';');
9846         switch (token.type) {
9847         case T_IDENTIFIER: {
9848                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
9849                 if (la1_type == ':') {
9850                         statement = parse_label_statement();
9851                 } else if (is_typedef_symbol(token.v.symbol)) {
9852                         statement = parse_declaration_statement();
9853                 } else switch (la1_type) {
9854                         case '*':
9855                                 if (get_declaration(token.v.symbol, NAMESPACE_NORMAL) != NULL)
9856                                         goto expression_statment;
9857                                 /* FALLTHROUGH */
9858
9859                         DECLARATION_START
9860                         case T_IDENTIFIER:
9861                                 statement = parse_declaration_statement();
9862                                 break;
9863
9864                         default:
9865 expression_statment:
9866                                 statement = parse_expression_statement();
9867                                 break;
9868                 }
9869                 break;
9870         }
9871
9872         case T___extension__:
9873                 /* This can be a prefix to a declaration or an expression statement.
9874                  * We simply eat it now and parse the rest with tail recursion. */
9875                 do {
9876                         next_token();
9877                 } while (token.type == T___extension__);
9878                 bool old_gcc_extension = in_gcc_extension;
9879                 in_gcc_extension       = true;
9880                 statement = parse_statement();
9881                 in_gcc_extension = old_gcc_extension;
9882                 break;
9883
9884         DECLARATION_START
9885                 statement = parse_declaration_statement();
9886                 break;
9887
9888         case T___label__:
9889                 statement = parse_local_label_declaration();
9890                 break;
9891
9892         case ';':        statement = parse_empty_statement();         break;
9893         case '{':        statement = parse_compound_statement(false); break;
9894         case T___leave:  statement = parse_leave_statement();         break;
9895         case T___try:    statement = parse_ms_try_statment();         break;
9896         case T_asm:      statement = parse_asm_statement();           break;
9897         case T_break:    statement = parse_break();                   break;
9898         case T_case:     statement = parse_case_statement();          break;
9899         case T_continue: statement = parse_continue();                break;
9900         case T_default:  statement = parse_default_statement();       break;
9901         case T_do:       statement = parse_do();                      break;
9902         case T_for:      statement = parse_for();                     break;
9903         case T_goto:     statement = parse_goto();                    break;
9904         case T_if:       statement = parse_if();                      break;
9905         case T_return:   statement = parse_return();                  break;
9906         case T_switch:   statement = parse_switch();                  break;
9907         case T_while:    statement = parse_while();                   break;
9908
9909         case '!':
9910         case '&':
9911         case '(':
9912         case '*':
9913         case '+':
9914         case '-':
9915         case '~':
9916         case T_ANDAND:
9917         case T_CHARACTER_CONSTANT:
9918         case T_FLOATINGPOINT:
9919         case T_INTEGER:
9920         case T_MINUSMINUS:
9921         case T_PLUSPLUS:
9922         case T_STRING_LITERAL:
9923         case T_WIDE_CHARACTER_CONSTANT:
9924         case T_WIDE_STRING_LITERAL:
9925         case T___FUNCDNAME__:
9926         case T___FUNCSIG__:
9927         case T___FUNCTION__:
9928         case T___PRETTY_FUNCTION__:
9929         case T___builtin_alloca:
9930         case T___builtin_classify_type:
9931         case T___builtin_constant_p:
9932         case T___builtin_expect:
9933         case T___builtin_huge_val:
9934         case T___builtin_isgreater:
9935         case T___builtin_isgreaterequal:
9936         case T___builtin_isless:
9937         case T___builtin_islessequal:
9938         case T___builtin_islessgreater:
9939         case T___builtin_isunordered:
9940         case T___builtin_inf:
9941         case T___builtin_inff:
9942         case T___builtin_infl:
9943         case T___builtin_nan:
9944         case T___builtin_nanf:
9945         case T___builtin_nanl:
9946         case T___builtin_offsetof:
9947         case T___builtin_prefetch:
9948         case T___builtin_va_arg:
9949         case T___builtin_va_end:
9950         case T___builtin_va_start:
9951         case T___func__:
9952         case T___noop:
9953         case T__assume:
9954                 statement = parse_expression_statement();
9955                 break;
9956
9957         default:
9958                 errorf(HERE, "unexpected token %K while parsing statement", &token);
9959                 statement = create_invalid_statement();
9960                 if (!at_anchor())
9961                         next_token();
9962                 break;
9963         }
9964         rem_anchor_token(';');
9965
9966         assert(statement != NULL
9967                         && statement->base.source_position.input_name != NULL);
9968
9969         return statement;
9970 }
9971
9972 /**
9973  * parse a statement and emits "statement has no effect" warning if needed
9974  * (This is really a wrapper around intern_parse_statement with check for 1
9975  *  single warning. It is needed, because for statement expressions we have
9976  *  to avoid the warning on the last statement)
9977  */
9978 static statement_t *parse_statement(void)
9979 {
9980         statement_t *statement = intern_parse_statement();
9981
9982         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
9983                 expression_t *expression = statement->expression.expression;
9984                 if (!expression_has_effect(expression)) {
9985                         warningf(&expression->base.source_position,
9986                                         "statement has no effect");
9987                 }
9988         }
9989
9990         return statement;
9991 }
9992
9993 /**
9994  * Parse a compound statement.
9995  */
9996 static statement_t *parse_compound_statement(bool inside_expression_statement)
9997 {
9998         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
9999
10000         PUSH_PARENT(statement);
10001
10002         eat('{');
10003         add_anchor_token('}');
10004
10005         size_t const top       = environment_top();
10006         size_t const top_local = local_label_top();
10007         scope_push(&statement->compound.scope);
10008
10009         statement_t **anchor            = &statement->compound.statements;
10010         bool          only_decls_so_far = true;
10011         while (token.type != '}') {
10012                 if (token.type == T_EOF) {
10013                         errorf(&statement->base.source_position,
10014                                "EOF while parsing compound statement");
10015                         break;
10016                 }
10017                 statement_t *sub_statement = intern_parse_statement();
10018                 if (is_invalid_statement(sub_statement)) {
10019                         /* an error occurred. if we are at an anchor, return */
10020                         if (at_anchor())
10021                                 goto end_error;
10022                         continue;
10023                 }
10024
10025                 if (warning.declaration_after_statement) {
10026                         if (sub_statement->kind != STATEMENT_DECLARATION) {
10027                                 only_decls_so_far = false;
10028                         } else if (!only_decls_so_far) {
10029                                 warningf(&sub_statement->base.source_position,
10030                                          "ISO C90 forbids mixed declarations and code");
10031                         }
10032                 }
10033
10034                 *anchor = sub_statement;
10035
10036                 while (sub_statement->base.next != NULL)
10037                         sub_statement = sub_statement->base.next;
10038
10039                 anchor = &sub_statement->base.next;
10040         }
10041         next_token();
10042
10043         /* look over all statements again to produce no effect warnings */
10044         if (warning.unused_value) {
10045                 statement_t *sub_statement = statement->compound.statements;
10046                 for( ; sub_statement != NULL; sub_statement = sub_statement->base.next) {
10047                         if (sub_statement->kind != STATEMENT_EXPRESSION)
10048                                 continue;
10049                         /* don't emit a warning for the last expression in an expression
10050                          * statement as it has always an effect */
10051                         if (inside_expression_statement && sub_statement->base.next == NULL)
10052                                 continue;
10053
10054                         expression_t *expression = sub_statement->expression.expression;
10055                         if (!expression_has_effect(expression)) {
10056                                 warningf(&expression->base.source_position,
10057                                          "statement has no effect");
10058                         }
10059                 }
10060         }
10061
10062 end_error:
10063         rem_anchor_token('}');
10064         assert(scope == &statement->compound.scope);
10065         scope_pop();
10066         environment_pop_to(top);
10067         local_label_pop_to(top_local);
10068
10069         POP_PARENT;
10070         return statement;
10071 }
10072
10073 /**
10074  * Initialize builtin types.
10075  */
10076 static void initialize_builtin_types(void)
10077 {
10078         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
10079         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
10080         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
10081         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
10082         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
10083         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
10084         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    opt_short_wchar_t ? type_unsigned_short : type_int);
10085         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
10086
10087         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
10088         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
10089         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
10090         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
10091
10092         /* const version of wchar_t */
10093         type_const_wchar_t = allocate_type_zero(TYPE_TYPEDEF, &builtin_source_position);
10094         type_const_wchar_t->typedeft.declaration  = type_wchar_t->typedeft.declaration;
10095         type_const_wchar_t->base.qualifiers      |= TYPE_QUALIFIER_CONST;
10096
10097         type_const_wchar_t_ptr = make_pointer_type(type_const_wchar_t, TYPE_QUALIFIER_NONE);
10098 }
10099
10100 /**
10101  * Check for unused global static functions and variables
10102  */
10103 static void check_unused_globals(void)
10104 {
10105         if (!warning.unused_function && !warning.unused_variable)
10106                 return;
10107
10108         for (const declaration_t *decl = file_scope->declarations; decl != NULL; decl = decl->next) {
10109                 if (decl->used                  ||
10110                     decl->modifiers & DM_UNUSED ||
10111                     decl->modifiers & DM_USED   ||
10112                     decl->storage_class != STORAGE_CLASS_STATIC)
10113                         continue;
10114
10115                 type_t *const type = decl->type;
10116                 const char *s;
10117                 if (is_type_function(skip_typeref(type))) {
10118                         if (!warning.unused_function || decl->is_inline)
10119                                 continue;
10120
10121                         s = (decl->init.statement != NULL ? "defined" : "declared");
10122                 } else {
10123                         if (!warning.unused_variable)
10124                                 continue;
10125
10126                         s = "defined";
10127                 }
10128
10129                 warningf(&decl->source_position, "'%#T' %s but not used",
10130                         type, decl->symbol, s);
10131         }
10132 }
10133
10134 static void parse_global_asm(void)
10135 {
10136         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
10137
10138         eat(T_asm);
10139         expect('(');
10140
10141         statement->asms.asm_text = parse_string_literals();
10142         statement->base.next     = unit->global_asm;
10143         unit->global_asm         = statement;
10144
10145         expect(')');
10146         expect(';');
10147
10148 end_error:;
10149 }
10150
10151 /**
10152  * Parse a translation unit.
10153  */
10154 static void parse_translation_unit(void)
10155 {
10156         add_anchor_token(T_EOF);
10157
10158 #ifndef NDEBUG
10159         unsigned char token_anchor_copy[T_LAST_TOKEN];
10160         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
10161 #endif
10162         for (;;) {
10163 #ifndef NDEBUG
10164                 bool anchor_leak = false;
10165                 for (int i = 0; i != T_LAST_TOKEN; ++i) {
10166                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
10167                         if (count != 0) {
10168                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
10169                                 anchor_leak = true;
10170                         }
10171                 }
10172                 if (in_gcc_extension) {
10173                         errorf(HERE, "Leaked __extension__");
10174                         anchor_leak = true;
10175                 }
10176
10177                 if (anchor_leak)
10178                         abort();
10179 #endif
10180
10181                 switch (token.type) {
10182                         DECLARATION_START
10183                         case T_IDENTIFIER:
10184                         case T___extension__:
10185                                 parse_external_declaration();
10186                                 break;
10187
10188                         case T_asm:
10189                                 parse_global_asm();
10190                                 break;
10191
10192                         case T_EOF:
10193                                 rem_anchor_token(T_EOF);
10194                                 return;
10195
10196                         case ';':
10197                                 if (!strict_mode) {
10198                                         warningf(HERE, "stray ';' outside of function");
10199                                         next_token();
10200                                         break;
10201                                 }
10202                                 /* FALLTHROUGH */
10203
10204                         default:
10205                                 errorf(HERE, "stray %K outside of function", &token);
10206                                 if (token.type == '(' || token.type == '{' || token.type == '[')
10207                                         eat_until_matching_token(token.type);
10208                                 next_token();
10209                                 break;
10210                 }
10211         }
10212 }
10213
10214 /**
10215  * Parse the input.
10216  *
10217  * @return  the translation unit or NULL if errors occurred.
10218  */
10219 void start_parsing(void)
10220 {
10221         environment_stack = NEW_ARR_F(stack_entry_t, 0);
10222         label_stack       = NEW_ARR_F(stack_entry_t, 0);
10223         local_label_stack = NEW_ARR_F(stack_entry_t, 0);
10224         diagnostic_count  = 0;
10225         error_count       = 0;
10226         warning_count     = 0;
10227
10228         type_set_output(stderr);
10229         ast_set_output(stderr);
10230
10231         assert(unit == NULL);
10232         unit = allocate_ast_zero(sizeof(unit[0]));
10233
10234         assert(file_scope == NULL);
10235         file_scope = &unit->scope;
10236
10237         assert(scope == NULL);
10238         scope_push(&unit->scope);
10239
10240         initialize_builtin_types();
10241 }
10242
10243 translation_unit_t *finish_parsing(void)
10244 {
10245         /* do NOT use scope_pop() here, this will crash, will it by hand */
10246         assert(scope == &unit->scope);
10247         scope            = NULL;
10248         last_declaration = NULL;
10249
10250         assert(file_scope == &unit->scope);
10251         check_unused_globals();
10252         file_scope = NULL;
10253
10254         DEL_ARR_F(environment_stack);
10255         DEL_ARR_F(label_stack);
10256         DEL_ARR_F(local_label_stack);
10257
10258         translation_unit_t *result = unit;
10259         unit = NULL;
10260         return result;
10261 }
10262
10263 void parse(void)
10264 {
10265         lookahead_bufpos = 0;
10266         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
10267                 next_token();
10268         }
10269         parse_translation_unit();
10270 }
10271
10272 /**
10273  * Initialize the parser.
10274  */
10275 void init_parser(void)
10276 {
10277         sym_anonymous = symbol_table_insert("<anonymous>");
10278
10279         if (c_mode & _MS) {
10280                 /* add predefined symbols for extended-decl-modifier */
10281                 sym_align      = symbol_table_insert("align");
10282                 sym_allocate   = symbol_table_insert("allocate");
10283                 sym_dllimport  = symbol_table_insert("dllimport");
10284                 sym_dllexport  = symbol_table_insert("dllexport");
10285                 sym_naked      = symbol_table_insert("naked");
10286                 sym_noinline   = symbol_table_insert("noinline");
10287                 sym_noreturn   = symbol_table_insert("noreturn");
10288                 sym_nothrow    = symbol_table_insert("nothrow");
10289                 sym_novtable   = symbol_table_insert("novtable");
10290                 sym_property   = symbol_table_insert("property");
10291                 sym_get        = symbol_table_insert("get");
10292                 sym_put        = symbol_table_insert("put");
10293                 sym_selectany  = symbol_table_insert("selectany");
10294                 sym_thread     = symbol_table_insert("thread");
10295                 sym_uuid       = symbol_table_insert("uuid");
10296                 sym_deprecated = symbol_table_insert("deprecated");
10297                 sym_restrict   = symbol_table_insert("restrict");
10298                 sym_noalias    = symbol_table_insert("noalias");
10299         }
10300         memset(token_anchor_set, 0, sizeof(token_anchor_set));
10301
10302         init_expression_parsers();
10303         obstack_init(&temp_obst);
10304
10305         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
10306         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
10307 }
10308
10309 /**
10310  * Terminate the parser.
10311  */
10312 void exit_parser(void)
10313 {
10314         obstack_free(&temp_obst, NULL);
10315 }