nsz Git - cparser/blob - parser.c

   1 /*
   2  * This file is part of cparser.
   3  * Copyright (C) 2007-2009 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 "entity_t.h"
  37 #include "attribute_t.h"
  38 #include "lang_features.h"
  39 #include "walk_statements.h"
  40 #include "warning.h"
  41 #include "printer.h"
  42 #include "adt/bitfiddle.h"
  43 #include "adt/error.h"
  44 #include "adt/array.h"
  45
  46 //#define PRINT_TOKENS
  47 #define MAX_LOOKAHEAD 1
  48
  49 typedef struct {
  50         entity_t           *old_entity;
  51         symbol_t           *symbol;
  52         entity_namespace_t  namespc;
  53 } stack_entry_t;
  54
  55 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  56 struct declaration_specifiers_t {
  57         source_position_t  source_position;
  58         storage_class_t    storage_class;
  59         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  60         bool               is_inline    : 1;
  61         bool               thread_local : 1;  /**< GCC __thread */
  62         attribute_t       *attributes;        /**< list of attributes */
  63         type_t            *type;
  64 };
  65
  66 /**
  67  * An environment for parsing initializers (and compound literals).
  68  */
  69 typedef struct parse_initializer_env_t {
  70         type_t     *type;   /**< the type of the initializer. In case of an
  71                                  array type with unspecified size this gets
  72                                  adjusted to the actual size. */
  73         entity_t   *entity; /**< the variable that is initialized if any */
  74         bool        must_be_constant;
  75 } parse_initializer_env_t;
  76
  77 typedef entity_t* (*parsed_declaration_func) (entity_t *declaration, bool is_definition);
  78
  79 /** The current token. */
  80 static token_t              token;
  81 /** The lookahead ring-buffer. */
  82 static token_t              lookahead_buffer[MAX_LOOKAHEAD];
  83 /** Position of the next token in the lookahead buffer. */
  84 static size_t               lookahead_bufpos;
  85 static stack_entry_t       *environment_stack = NULL;
  86 static stack_entry_t       *label_stack       = NULL;
  87 static scope_t             *file_scope        = NULL;
  88 static scope_t             *current_scope     = NULL;
  89 /** Point to the current function declaration if inside a function. */
  90 static function_t          *current_function  = NULL;
  91 static entity_t            *current_entity    = NULL;
  92 static entity_t            *current_init_decl = NULL;
  93 static switch_statement_t  *current_switch    = NULL;
  94 static statement_t         *current_loop      = NULL;
  95 static statement_t         *current_parent    = NULL;
  96 static ms_try_statement_t  *current_try       = NULL;
  97 static linkage_kind_t       current_linkage   = LINKAGE_INVALID;
  98 static goto_statement_t    *goto_first        = NULL;
  99 static goto_statement_t   **goto_anchor       = NULL;
 100 static label_statement_t   *label_first       = NULL;
 101 static label_statement_t  **label_anchor      = NULL;
 102 /** current translation unit. */
 103 static translation_unit_t  *unit              = NULL;
 104 /** true if we are in a type property context (evaluation only for type) */
 105 static bool                 in_type_prop      = false;
 106 /** true if we are in an __extension__ context. */
 107 static bool                 in_gcc_extension  = false;
 108 static struct obstack       temp_obst;
 109 static entity_t            *anonymous_entity;
 110 static declaration_t      **incomplete_arrays;
 111 static elf_visibility_tag_t default_visibility = ELF_VISIBILITY_DEFAULT;
 112
 113
 114 #define PUSH_PARENT(stmt)                          \
 115         statement_t *const prev_parent = current_parent; \
 116         ((void)(current_parent = (stmt)))
 117 #define POP_PARENT ((void)(current_parent = prev_parent))
 118
 119 /** special symbol used for anonymous entities. */
 120 static symbol_t *sym_anonymous = NULL;
 121
 122 /** The token anchor set */
 123 static unsigned char token_anchor_set[T_LAST_TOKEN];
 124
 125 /** The current source position. */
 126 #define HERE (&token.source_position)
 127
 128 /** true if we are in GCC mode. */
 129 #define GNU_MODE ((c_mode & _GNUC) || in_gcc_extension)
 130
 131 static statement_t *parse_compound_statement(bool inside_expression_statement);
 132 static statement_t *parse_statement(void);
 133
 134 static expression_t *parse_subexpression(precedence_t);
 135 static expression_t *parse_expression(void);
 136 static type_t       *parse_typename(void);
 137 static void          parse_externals(void);
 138 static void          parse_external(void);
 139
 140 static void parse_compound_type_entries(compound_t *compound_declaration);
 141
 142 static void check_call_argument(type_t          *expected_type,
 143                                                                 call_argument_t *argument, unsigned pos);
 144
 145 typedef enum declarator_flags_t {
 146         DECL_FLAGS_NONE             = 0,
 147         DECL_MAY_BE_ABSTRACT        = 1U << 0,
 148         DECL_CREATE_COMPOUND_MEMBER = 1U << 1,
 149         DECL_IS_PARAMETER           = 1U << 2
 150 } declarator_flags_t;
 151
 152 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
 153                                   declarator_flags_t flags);
 154
 155 static void semantic_comparison(binary_expression_t *expression);
 156
 157 #define STORAGE_CLASSES       \
 158         STORAGE_CLASSES_NO_EXTERN \
 159         case T_extern:
 160
 161 #define STORAGE_CLASSES_NO_EXTERN \
 162         case T_typedef:         \
 163         case T_static:          \
 164         case T_auto:            \
 165         case T_register:        \
 166         case T___thread:
 167
 168 #define TYPE_QUALIFIERS     \
 169         case T_const:           \
 170         case T_restrict:        \
 171         case T_volatile:        \
 172         case T_inline:          \
 173         case T__forceinline:    \
 174         case T___attribute__:
 175
 176 #define COMPLEX_SPECIFIERS  \
 177         case T__Complex:
 178 #define IMAGINARY_SPECIFIERS \
 179         case T__Imaginary:
 180
 181 #define TYPE_SPECIFIERS       \
 182         case T__Bool:             \
 183         case T___builtin_va_list: \
 184         case T___typeof__:        \
 185         case T__declspec:         \
 186         case T_bool:              \
 187         case T_char:              \
 188         case T_double:            \
 189         case T_enum:              \
 190         case T_float:             \
 191         case T_int:               \
 192         case T_long:              \
 193         case T_short:             \
 194         case T_signed:            \
 195         case T_struct:            \
 196         case T_union:             \
 197         case T_unsigned:          \
 198         case T_void:              \
 199         case T_wchar_t:           \
 200         case T__int8:             \
 201         case T__int16:            \
 202         case T__int32:            \
 203         case T__int64:            \
 204         case T__int128:           \
 205         COMPLEX_SPECIFIERS        \
 206         IMAGINARY_SPECIFIERS
 207
 208 #define DECLARATION_START   \
 209         STORAGE_CLASSES         \
 210         TYPE_QUALIFIERS         \
 211         TYPE_SPECIFIERS
 212
 213 #define DECLARATION_START_NO_EXTERN \
 214         STORAGE_CLASSES_NO_EXTERN       \
 215         TYPE_QUALIFIERS                 \
 216         TYPE_SPECIFIERS
 217
 218 #define EXPRESSION_START              \
 219         case '!':                         \
 220         case '&':                         \
 221         case '(':                         \
 222         case '*':                         \
 223         case '+':                         \
 224         case '-':                         \
 225         case '~':                         \
 226         case T_ANDAND:                    \
 227         case T_CHARACTER_CONSTANT:        \
 228         case T_FLOATINGPOINT:             \
 229         case T_FLOATINGPOINT_HEXADECIMAL: \
 230         case T_INTEGER:                   \
 231         case T_INTEGER_HEXADECIMAL:       \
 232         case T_INTEGER_OCTAL:             \
 233         case T_MINUSMINUS:                \
 234         case T_PLUSPLUS:                  \
 235         case T_STRING_LITERAL:            \
 236         case T_WIDE_CHARACTER_CONSTANT:   \
 237         case T_WIDE_STRING_LITERAL:       \
 238         case T___FUNCDNAME__:             \
 239         case T___FUNCSIG__:               \
 240         case T___FUNCTION__:              \
 241         case T___PRETTY_FUNCTION__:       \
 242         case T___alignof__:               \
 243         case T___builtin_classify_type:   \
 244         case T___builtin_constant_p:      \
 245         case T___builtin_isgreater:       \
 246         case T___builtin_isgreaterequal:  \
 247         case T___builtin_isless:          \
 248         case T___builtin_islessequal:     \
 249         case T___builtin_islessgreater:   \
 250         case T___builtin_isunordered:     \
 251         case T___builtin_offsetof:        \
 252         case T___builtin_va_arg:          \
 253         case T___builtin_va_copy:         \
 254         case T___builtin_va_start:        \
 255         case T___func__:                  \
 256         case T___noop:                    \
 257         case T__assume:                   \
 258         case T_delete:                    \
 259         case T_false:                     \
 260         case T_sizeof:                    \
 261         case T_throw:                     \
 262         case T_true:
 263
 264 /**
 265  * Returns the size of a statement node.
 266  *
 267  * @param kind  the statement kind
 268  */
 269 static size_t get_statement_struct_size(statement_kind_t kind)
 270 {
 271         static const size_t sizes[] = {
 272                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 273                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 274                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 275                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 276                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 277                 [STATEMENT_IF]          = sizeof(if_statement_t),
 278                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 279                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 280                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 281                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 282                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 283                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 284                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 285                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 286                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 287                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 288                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 289                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 290                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 291         };
 292         assert(kind < lengthof(sizes));
 293         assert(sizes[kind] != 0);
 294         return sizes[kind];
 295 }
 296
 297 /**
 298  * Returns the size of an expression node.
 299  *
 300  * @param kind  the expression kind
 301  */
 302 static size_t get_expression_struct_size(expression_kind_t kind)
 303 {
 304         static const size_t sizes[] = {
 305                 [EXPR_INVALID]                    = sizeof(expression_base_t),
 306                 [EXPR_REFERENCE]                  = sizeof(reference_expression_t),
 307                 [EXPR_REFERENCE_ENUM_VALUE]       = sizeof(reference_expression_t),
 308                 [EXPR_LITERAL_BOOLEAN]            = sizeof(literal_expression_t),
 309                 [EXPR_LITERAL_INTEGER]            = sizeof(literal_expression_t),
 310                 [EXPR_LITERAL_INTEGER_OCTAL]      = sizeof(literal_expression_t),
 311                 [EXPR_LITERAL_INTEGER_HEXADECIMAL]= sizeof(literal_expression_t),
 312                 [EXPR_LITERAL_FLOATINGPOINT]      = sizeof(literal_expression_t),
 313                 [EXPR_LITERAL_FLOATINGPOINT_HEXADECIMAL] = sizeof(literal_expression_t),
 314                 [EXPR_LITERAL_CHARACTER]          = sizeof(literal_expression_t),
 315                 [EXPR_LITERAL_WIDE_CHARACTER]     = sizeof(literal_expression_t),
 316                 [EXPR_STRING_LITERAL]             = sizeof(string_literal_expression_t),
 317                 [EXPR_WIDE_STRING_LITERAL]        = sizeof(string_literal_expression_t),
 318                 [EXPR_COMPOUND_LITERAL]           = sizeof(compound_literal_expression_t),
 319                 [EXPR_CALL]                       = sizeof(call_expression_t),
 320                 [EXPR_UNARY_FIRST]                = sizeof(unary_expression_t),
 321                 [EXPR_BINARY_FIRST]               = sizeof(binary_expression_t),
 322                 [EXPR_CONDITIONAL]                = sizeof(conditional_expression_t),
 323                 [EXPR_SELECT]                     = sizeof(select_expression_t),
 324                 [EXPR_ARRAY_ACCESS]               = sizeof(array_access_expression_t),
 325                 [EXPR_SIZEOF]                     = sizeof(typeprop_expression_t),
 326                 [EXPR_ALIGNOF]                    = sizeof(typeprop_expression_t),
 327                 [EXPR_CLASSIFY_TYPE]              = sizeof(classify_type_expression_t),
 328                 [EXPR_FUNCNAME]                   = sizeof(funcname_expression_t),
 329                 [EXPR_BUILTIN_CONSTANT_P]         = sizeof(builtin_constant_expression_t),
 330                 [EXPR_BUILTIN_TYPES_COMPATIBLE_P] = sizeof(builtin_types_compatible_expression_t),
 331                 [EXPR_OFFSETOF]                   = sizeof(offsetof_expression_t),
 332                 [EXPR_VA_START]                   = sizeof(va_start_expression_t),
 333                 [EXPR_VA_ARG]                     = sizeof(va_arg_expression_t),
 334                 [EXPR_VA_COPY]                    = sizeof(va_copy_expression_t),
 335                 [EXPR_STATEMENT]                  = sizeof(statement_expression_t),
 336                 [EXPR_LABEL_ADDRESS]              = sizeof(label_address_expression_t),
 337         };
 338         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 339                 return sizes[EXPR_UNARY_FIRST];
 340         }
 341         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 342                 return sizes[EXPR_BINARY_FIRST];
 343         }
 344         assert(kind < lengthof(sizes));
 345         assert(sizes[kind] != 0);
 346         return sizes[kind];
 347 }
 348
 349 /**
 350  * Allocate a statement node of given kind and initialize all
 351  * fields with zero. Sets its source position to the position
 352  * of the current token.
 353  */
 354 static statement_t *allocate_statement_zero(statement_kind_t kind)
 355 {
 356         size_t       size = get_statement_struct_size(kind);
 357         statement_t *res  = allocate_ast_zero(size);
 358
 359         res->base.kind            = kind;
 360         res->base.parent          = current_parent;
 361         res->base.source_position = token.source_position;
 362         return res;
 363 }
 364
 365 /**
 366  * Allocate an expression node of given kind and initialize all
 367  * fields with zero.
 368  *
 369  * @param kind  the kind of the expression to allocate
 370  */
 371 static expression_t *allocate_expression_zero(expression_kind_t kind)
 372 {
 373         size_t        size = get_expression_struct_size(kind);
 374         expression_t *res  = allocate_ast_zero(size);
 375
 376         res->base.kind            = kind;
 377         res->base.type            = type_error_type;
 378         res->base.source_position = token.source_position;
 379         return res;
 380 }
 381
 382 /**
 383  * Creates a new invalid expression at the source position
 384  * of the current token.
 385  */
 386 static expression_t *create_invalid_expression(void)
 387 {
 388         return allocate_expression_zero(EXPR_INVALID);
 389 }
 390
 391 /**
 392  * Creates a new invalid statement.
 393  */
 394 static statement_t *create_invalid_statement(void)
 395 {
 396         return allocate_statement_zero(STATEMENT_INVALID);
 397 }
 398
 399 /**
 400  * Allocate a new empty statement.
 401  */
 402 static statement_t *create_empty_statement(void)
 403 {
 404         return allocate_statement_zero(STATEMENT_EMPTY);
 405 }
 406
 407 static function_parameter_t *allocate_parameter(type_t *const type)
 408 {
 409         function_parameter_t *const param
 410                 = obstack_alloc(type_obst, sizeof(*param));
 411         memset(param, 0, sizeof(*param));
 412         param->type = type;
 413         return param;
 414 }
 415
 416 /**
 417  * Returns the size of an initializer node.
 418  *
 419  * @param kind  the initializer kind
 420  */
 421 static size_t get_initializer_size(initializer_kind_t kind)
 422 {
 423         static const size_t sizes[] = {
 424                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 425                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 426                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 427                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 428                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 429         };
 430         assert(kind < lengthof(sizes));
 431         assert(sizes[kind] != 0);
 432         return sizes[kind];
 433 }
 434
 435 /**
 436  * Allocate an initializer node of given kind and initialize all
 437  * fields with zero.
 438  */
 439 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 440 {
 441         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 442         result->kind          = kind;
 443
 444         return result;
 445 }
 446
 447 /**
 448  * Returns the index of the top element of the environment stack.
 449  */
 450 static size_t environment_top(void)
 451 {
 452         return ARR_LEN(environment_stack);
 453 }
 454
 455 /**
 456  * Returns the index of the top element of the global label stack.
 457  */
 458 static size_t label_top(void)
 459 {
 460         return ARR_LEN(label_stack);
 461 }
 462
 463 /**
 464  * Return the next token.
 465  */
 466 static inline void next_token(void)
 467 {
 468         token                              = lookahead_buffer[lookahead_bufpos];
 469         lookahead_buffer[lookahead_bufpos] = lexer_token;
 470         lexer_next_token();
 471
 472         lookahead_bufpos = (lookahead_bufpos + 1) % MAX_LOOKAHEAD;
 473
 474 #ifdef PRINT_TOKENS
 475         print_token(stderr, &token);
 476         fprintf(stderr, "\n");
 477 #endif
 478 }
 479
 480 static inline bool next_if(int const type)
 481 {
 482         if (token.type == type) {
 483                 next_token();
 484                 return true;
 485         } else {
 486                 return false;
 487         }
 488 }
 489
 490 /**
 491  * Return the next token with a given lookahead.
 492  */
 493 static inline const token_t *look_ahead(size_t num)
 494 {
 495         assert(0 < num && num <= MAX_LOOKAHEAD);
 496         size_t pos = (lookahead_bufpos + num - 1) % MAX_LOOKAHEAD;
 497         return &lookahead_buffer[pos];
 498 }
 499
 500 /**
 501  * Adds a token type to the token type anchor set (a multi-set).
 502  */
 503 static void add_anchor_token(int token_type)
 504 {
 505         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 506         ++token_anchor_set[token_type];
 507 }
 508
 509 /**
 510  * Set the number of tokens types of the given type
 511  * to zero and return the old count.
 512  */
 513 static int save_and_reset_anchor_state(int token_type)
 514 {
 515         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 516         int count = token_anchor_set[token_type];
 517         token_anchor_set[token_type] = 0;
 518         return count;
 519 }
 520
 521 /**
 522  * Restore the number of token types to the given count.
 523  */
 524 static void restore_anchor_state(int token_type, int count)
 525 {
 526         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 527         token_anchor_set[token_type] = count;
 528 }
 529
 530 /**
 531  * Remove a token type from the token type anchor set (a multi-set).
 532  */
 533 static void rem_anchor_token(int token_type)
 534 {
 535         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 536         assert(token_anchor_set[token_type] != 0);
 537         --token_anchor_set[token_type];
 538 }
 539
 540 /**
 541  * Return true if the token type of the current token is
 542  * in the anchor set.
 543  */
 544 static bool at_anchor(void)
 545 {
 546         if (token.type < 0)
 547                 return false;
 548         return token_anchor_set[token.type];
 549 }
 550
 551 /**
 552  * Eat tokens until a matching token type is found.
 553  */
 554 static void eat_until_matching_token(int type)
 555 {
 556         int end_token;
 557         switch (type) {
 558                 case '(': end_token = ')';  break;
 559                 case '{': end_token = '}';  break;
 560                 case '[': end_token = ']';  break;
 561                 default:  end_token = type; break;
 562         }
 563
 564         unsigned parenthesis_count = 0;
 565         unsigned brace_count       = 0;
 566         unsigned bracket_count     = 0;
 567         while (token.type        != end_token ||
 568                parenthesis_count != 0         ||
 569                brace_count       != 0         ||
 570                bracket_count     != 0) {
 571                 switch (token.type) {
 572                 case T_EOF: return;
 573                 case '(': ++parenthesis_count; break;
 574                 case '{': ++brace_count;       break;
 575                 case '[': ++bracket_count;     break;
 576
 577                 case ')':
 578                         if (parenthesis_count > 0)
 579                                 --parenthesis_count;
 580                         goto check_stop;
 581
 582                 case '}':
 583                         if (brace_count > 0)
 584                                 --brace_count;
 585                         goto check_stop;
 586
 587                 case ']':
 588                         if (bracket_count > 0)
 589                                 --bracket_count;
 590 check_stop:
 591                         if (token.type        == end_token &&
 592                             parenthesis_count == 0         &&
 593                             brace_count       == 0         &&
 594                             bracket_count     == 0)
 595                                 return;
 596                         break;
 597
 598                 default:
 599                         break;
 600                 }
 601                 next_token();
 602         }
 603 }
 604
 605 /**
 606  * Eat input tokens until an anchor is found.
 607  */
 608 static void eat_until_anchor(void)
 609 {
 610         while (token_anchor_set[token.type] == 0) {
 611                 if (token.type == '(' || token.type == '{' || token.type == '[')
 612                         eat_until_matching_token(token.type);
 613                 next_token();
 614         }
 615 }
 616
 617 /**
 618  * Eat a whole block from input tokens.
 619  */
 620 static void eat_block(void)
 621 {
 622         eat_until_matching_token('{');
 623         next_if('}');
 624 }
 625
 626 #define eat(token_type) (assert(token.type == (token_type)), next_token())
 627
 628 /**
 629  * Report a parse error because an expected token was not found.
 630  */
 631 static
 632 #if defined __GNUC__ && __GNUC__ >= 4
 633 __attribute__((sentinel))
 634 #endif
 635 void parse_error_expected(const char *message, ...)
 636 {
 637         if (message != NULL) {
 638                 errorf(HERE, "%s", message);
 639         }
 640         va_list ap;
 641         va_start(ap, message);
 642         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 643         va_end(ap);
 644 }
 645
 646 /**
 647  * Report an incompatible type.
 648  */
 649 static void type_error_incompatible(const char *msg,
 650                 const source_position_t *source_position, type_t *type1, type_t *type2)
 651 {
 652         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 653                msg, type1, type2);
 654 }
 655
 656 /**
 657  * Expect the current token is the expected token.
 658  * If not, generate an error, eat the current statement,
 659  * and goto the error_label label.
 660  */
 661 #define expect(expected, error_label)                     \
 662         do {                                                  \
 663                 if (UNLIKELY(token.type != (expected))) {         \
 664                         parse_error_expected(NULL, (expected), NULL); \
 665                         add_anchor_token(expected);                   \
 666                         eat_until_anchor();                           \
 667                         next_if((expected));                          \
 668                         rem_anchor_token(expected);                   \
 669                         goto error_label;                             \
 670                 }                                                 \
 671                 next_token();                                     \
 672         } while (0)
 673
 674 /**
 675  * Push a given scope on the scope stack and make it the
 676  * current scope
 677  */
 678 static scope_t *scope_push(scope_t *new_scope)
 679 {
 680         if (current_scope != NULL) {
 681                 new_scope->depth = current_scope->depth + 1;
 682         }
 683
 684         scope_t *old_scope = current_scope;
 685         current_scope      = new_scope;
 686         return old_scope;
 687 }
 688
 689 /**
 690  * Pop the current scope from the scope stack.
 691  */
 692 static void scope_pop(scope_t *old_scope)
 693 {
 694         current_scope = old_scope;
 695 }
 696
 697 /**
 698  * Search an entity by its symbol in a given namespace.
 699  */
 700 static entity_t *get_entity(const symbol_t *const symbol,
 701                             namespace_tag_t namespc)
 702 {
 703         assert(namespc != NAMESPACE_INVALID);
 704         entity_t *entity = symbol->entity;
 705         for (; entity != NULL; entity = entity->base.symbol_next) {
 706                 if (entity->base.namespc == namespc)
 707                         return entity;
 708         }
 709
 710         return NULL;
 711 }
 712
 713 /* §6.2.3:1 24)  There is only one name space for tags even though three are
 714  * possible. */
 715 static entity_t *get_tag(symbol_t const *const symbol,
 716                          entity_kind_tag_t const kind)
 717 {
 718         entity_t *entity = get_entity(symbol, NAMESPACE_TAG);
 719         if (entity != NULL && entity->kind != kind) {
 720                 errorf(HERE,
 721                                 "'%Y' defined as wrong kind of tag (previous definition %P)",
 722                                 symbol, &entity->base.source_position);
 723                 entity = NULL;
 724         }
 725         return entity;
 726 }
 727
 728 /**
 729  * pushs an entity on the environment stack and links the corresponding symbol
 730  * it.
 731  */
 732 static void stack_push(stack_entry_t **stack_ptr, entity_t *entity)
 733 {
 734         symbol_t           *symbol  = entity->base.symbol;
 735         entity_namespace_t  namespc = entity->base.namespc;
 736         assert(namespc != NAMESPACE_INVALID);
 737
 738         /* replace/add entity into entity list of the symbol */
 739         entity_t **anchor;
 740         entity_t  *iter;
 741         for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 742                 iter = *anchor;
 743                 if (iter == NULL)
 744                         break;
 745
 746                 /* replace an entry? */
 747                 if (iter->base.namespc == namespc) {
 748                         entity->base.symbol_next = iter->base.symbol_next;
 749                         break;
 750                 }
 751         }
 752         *anchor = entity;
 753
 754         /* remember old declaration */
 755         stack_entry_t entry;
 756         entry.symbol     = symbol;
 757         entry.old_entity = iter;
 758         entry.namespc    = namespc;
 759         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 760 }
 761
 762 /**
 763  * Push an entity on the environment stack.
 764  */
 765 static void environment_push(entity_t *entity)
 766 {
 767         assert(entity->base.source_position.input_name != NULL);
 768         assert(entity->base.parent_scope != NULL);
 769         stack_push(&environment_stack, entity);
 770 }
 771
 772 /**
 773  * Push a declaration on the global label stack.
 774  *
 775  * @param declaration  the declaration
 776  */
 777 static void label_push(entity_t *label)
 778 {
 779         /* we abuse the parameters scope as parent for the labels */
 780         label->base.parent_scope = &current_function->parameters;
 781         stack_push(&label_stack, label);
 782 }
 783
 784 /**
 785  * pops symbols from the environment stack until @p new_top is the top element
 786  */
 787 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 788 {
 789         stack_entry_t *stack = *stack_ptr;
 790         size_t         top   = ARR_LEN(stack);
 791         size_t         i;
 792
 793         assert(new_top <= top);
 794         if (new_top == top)
 795                 return;
 796
 797         for (i = top; i > new_top; --i) {
 798                 stack_entry_t *entry = &stack[i - 1];
 799
 800                 entity_t           *old_entity = entry->old_entity;
 801                 symbol_t           *symbol     = entry->symbol;
 802                 entity_namespace_t  namespc    = entry->namespc;
 803
 804                 /* replace with old_entity/remove */
 805                 entity_t **anchor;
 806                 entity_t  *iter;
 807                 for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 808                         iter = *anchor;
 809                         assert(iter != NULL);
 810                         /* replace an entry? */
 811                         if (iter->base.namespc == namespc)
 812                                 break;
 813                 }
 814
 815                 /* restore definition from outer scopes (if there was one) */
 816                 if (old_entity != NULL) {
 817                         old_entity->base.symbol_next = iter->base.symbol_next;
 818                         *anchor                      = old_entity;
 819                 } else {
 820                         /* remove entry from list */
 821                         *anchor = iter->base.symbol_next;
 822                 }
 823         }
 824
 825         ARR_SHRINKLEN(*stack_ptr, new_top);
 826 }
 827
 828 /**
 829  * Pop all entries from the environment stack until the new_top
 830  * is reached.
 831  *
 832  * @param new_top  the new stack top
 833  */
 834 static void environment_pop_to(size_t new_top)
 835 {
 836         stack_pop_to(&environment_stack, new_top);
 837 }
 838
 839 /**
 840  * Pop all entries from the global label stack until the new_top
 841  * is reached.
 842  *
 843  * @param new_top  the new stack top
 844  */
 845 static void label_pop_to(size_t new_top)
 846 {
 847         stack_pop_to(&label_stack, new_top);
 848 }
 849
 850 static int get_akind_rank(atomic_type_kind_t akind)
 851 {
 852         return (int) akind;
 853 }
 854
 855 /**
 856  * Return the type rank for an atomic type.
 857  */
 858 static int get_rank(const type_t *type)
 859 {
 860         assert(!is_typeref(type));
 861         if (type->kind == TYPE_ENUM)
 862                 return get_akind_rank(type->enumt.akind);
 863
 864         assert(type->kind == TYPE_ATOMIC);
 865         return get_akind_rank(type->atomic.akind);
 866 }
 867
 868 /**
 869  * §6.3.1.1:2  Do integer promotion for a given type.
 870  *
 871  * @param type  the type to promote
 872  * @return the promoted type
 873  */
 874 static type_t *promote_integer(type_t *type)
 875 {
 876         if (type->kind == TYPE_BITFIELD)
 877                 type = type->bitfield.base_type;
 878
 879         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
 880                 type = type_int;
 881
 882         return type;
 883 }
 884
 885 /**
 886  * Create a cast expression.
 887  *
 888  * @param expression  the expression to cast
 889  * @param dest_type   the destination type
 890  */
 891 static expression_t *create_cast_expression(expression_t *expression,
 892                                             type_t *dest_type)
 893 {
 894         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
 895
 896         cast->unary.value = expression;
 897         cast->base.type   = dest_type;
 898
 899         return cast;
 900 }
 901
 902 /**
 903  * Check if a given expression represents a null pointer constant.
 904  *
 905  * @param expression  the expression to check
 906  */
 907 static bool is_null_pointer_constant(const expression_t *expression)
 908 {
 909         /* skip void* cast */
 910         if (expression->kind == EXPR_UNARY_CAST ||
 911                         expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
 912                 type_t *const type = skip_typeref(expression->base.type);
 913                 if (types_compatible(type, type_void_ptr))
 914                         expression = expression->unary.value;
 915         }
 916
 917         type_t *const type = skip_typeref(expression->base.type);
 918         if (!is_type_integer(type))
 919                 return false;
 920         switch (is_constant_expression(expression)) {
 921                 case EXPR_CLASS_ERROR:    return true;
 922                 case EXPR_CLASS_CONSTANT: return !fold_constant_to_bool(expression);
 923                 default:                  return false;
 924         }
 925 }
 926
 927 /**
 928  * Create an implicit cast expression.
 929  *
 930  * @param expression  the expression to cast
 931  * @param dest_type   the destination type
 932  */
 933 static expression_t *create_implicit_cast(expression_t *expression,
 934                                           type_t *dest_type)
 935 {
 936         type_t *const source_type = expression->base.type;
 937
 938         if (source_type == dest_type)
 939                 return expression;
 940
 941         return create_cast_expression(expression, dest_type);
 942 }
 943
 944 typedef enum assign_error_t {
 945         ASSIGN_SUCCESS,
 946         ASSIGN_ERROR_INCOMPATIBLE,
 947         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
 948         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
 949         ASSIGN_WARNING_POINTER_FROM_INT,
 950         ASSIGN_WARNING_INT_FROM_POINTER
 951 } assign_error_t;
 952
 953 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
 954                                 const expression_t *const right,
 955                                 const char *context,
 956                                 const source_position_t *source_position)
 957 {
 958         type_t *const orig_type_right = right->base.type;
 959         type_t *const type_left       = skip_typeref(orig_type_left);
 960         type_t *const type_right      = skip_typeref(orig_type_right);
 961
 962         switch (error) {
 963         case ASSIGN_SUCCESS:
 964                 return;
 965         case ASSIGN_ERROR_INCOMPATIBLE:
 966                 errorf(source_position,
 967                        "destination type '%T' in %s is incompatible with type '%T'",
 968                        orig_type_left, context, orig_type_right);
 969                 return;
 970
 971         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
 972                 if (warning.other) {
 973                         type_t *points_to_left  = skip_typeref(type_left->pointer.points_to);
 974                         type_t *points_to_right = skip_typeref(type_right->pointer.points_to);
 975
 976                         /* the left type has all qualifiers from the right type */
 977                         unsigned missing_qualifiers
 978                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
 979                         warningf(source_position,
 980                                         "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
 981                                         orig_type_left, context, orig_type_right, missing_qualifiers);
 982                 }
 983                 return;
 984         }
 985
 986         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
 987                 if (warning.other) {
 988                         warningf(source_position,
 989                                         "destination type '%T' in %s is incompatible with '%E' of type '%T'",
 990                                         orig_type_left, context, right, orig_type_right);
 991                 }
 992                 return;
 993
 994         case ASSIGN_WARNING_POINTER_FROM_INT:
 995                 if (warning.other) {
 996                         warningf(source_position,
 997                                         "%s makes pointer '%T' from integer '%T' without a cast",
 998                                         context, orig_type_left, orig_type_right);
 999                 }
1000                 return;
1001
1002         case ASSIGN_WARNING_INT_FROM_POINTER:
1003                 if (warning.other) {
1004                         warningf(source_position,
1005                                         "%s makes integer '%T' from pointer '%T' without a cast",
1006                                         context, orig_type_left, orig_type_right);
1007                 }
1008                 return;
1009
1010         default:
1011                 panic("invalid error value");
1012         }
1013 }
1014
1015 /** Implements the rules from §6.5.16.1 */
1016 static assign_error_t semantic_assign(type_t *orig_type_left,
1017                                       const expression_t *const right)
1018 {
1019         type_t *const orig_type_right = right->base.type;
1020         type_t *const type_left       = skip_typeref(orig_type_left);
1021         type_t *const type_right      = skip_typeref(orig_type_right);
1022
1023         if (is_type_pointer(type_left)) {
1024                 if (is_null_pointer_constant(right)) {
1025                         return ASSIGN_SUCCESS;
1026                 } else if (is_type_pointer(type_right)) {
1027                         type_t *points_to_left
1028                                 = skip_typeref(type_left->pointer.points_to);
1029                         type_t *points_to_right
1030                                 = skip_typeref(type_right->pointer.points_to);
1031                         assign_error_t res = ASSIGN_SUCCESS;
1032
1033                         /* the left type has all qualifiers from the right type */
1034                         unsigned missing_qualifiers
1035                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1036                         if (missing_qualifiers != 0) {
1037                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1038                         }
1039
1040                         points_to_left  = get_unqualified_type(points_to_left);
1041                         points_to_right = get_unqualified_type(points_to_right);
1042
1043                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID))
1044                                 return res;
1045
1046                         if (is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1047                                 /* ISO/IEC 14882:1998(E) §C.1.2:6 */
1048                                 return c_mode & _CXX ? ASSIGN_ERROR_INCOMPATIBLE : res;
1049                         }
1050
1051                         if (!types_compatible(points_to_left, points_to_right)) {
1052                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1053                         }
1054
1055                         return res;
1056                 } else if (is_type_integer(type_right)) {
1057                         return ASSIGN_WARNING_POINTER_FROM_INT;
1058                 }
1059         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1060                         (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1061                                 && is_type_pointer(type_right))) {
1062                 return ASSIGN_SUCCESS;
1063         } else if (is_type_compound(type_left) && is_type_compound(type_right)) {
1064                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1065                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1066                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1067                         return ASSIGN_SUCCESS;
1068                 }
1069         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1070                 return ASSIGN_WARNING_INT_FROM_POINTER;
1071         }
1072
1073         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1074                 return ASSIGN_SUCCESS;
1075
1076         return ASSIGN_ERROR_INCOMPATIBLE;
1077 }
1078
1079 static expression_t *parse_constant_expression(void)
1080 {
1081         expression_t *result = parse_subexpression(PREC_CONDITIONAL);
1082
1083         if (is_constant_expression(result) == EXPR_CLASS_VARIABLE) {
1084                 errorf(&result->base.source_position,
1085                        "expression '%E' is not constant", result);
1086         }
1087
1088         return result;
1089 }
1090
1091 static expression_t *parse_assignment_expression(void)
1092 {
1093         return parse_subexpression(PREC_ASSIGNMENT);
1094 }
1095
1096 static void warn_string_concat(const source_position_t *pos)
1097 {
1098         if (warning.traditional) {
1099                 warningf(pos, "traditional C rejects string constant concatenation");
1100         }
1101 }
1102
1103 static string_t parse_string_literals(void)
1104 {
1105         assert(token.type == T_STRING_LITERAL);
1106         string_t result = token.literal;
1107
1108         next_token();
1109
1110         while (token.type == T_STRING_LITERAL) {
1111                 warn_string_concat(&token.source_position);
1112                 result = concat_strings(&result, &token.literal);
1113                 next_token();
1114         }
1115
1116         return result;
1117 }
1118
1119 /**
1120  * compare two string, ignoring double underscores on the second.
1121  */
1122 static int strcmp_underscore(const char *s1, const char *s2)
1123 {
1124         if (s2[0] == '_' && s2[1] == '_') {
1125                 size_t len2 = strlen(s2);
1126                 size_t len1 = strlen(s1);
1127                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1128                         return strncmp(s1, s2+2, len2-4);
1129                 }
1130         }
1131
1132         return strcmp(s1, s2);
1133 }
1134
1135 static attribute_t *allocate_attribute_zero(attribute_kind_t kind)
1136 {
1137         attribute_t *attribute = allocate_ast_zero(sizeof(*attribute));
1138         attribute->kind        = kind;
1139         return attribute;
1140 }
1141
1142 /**
1143  * Parse (gcc) attribute argument. From gcc comments in gcc source:
1144  *
1145  *  attribute:
1146  *    __attribute__ ( ( attribute-list ) )
1147  *
1148  *  attribute-list:
1149  *    attrib
1150  *    attribute_list , attrib
1151  *
1152  *  attrib:
1153  *    empty
1154  *    any-word
1155  *    any-word ( identifier )
1156  *    any-word ( identifier , nonempty-expr-list )
1157  *    any-word ( expr-list )
1158  *
1159  *  where the "identifier" must not be declared as a type, and
1160  *  "any-word" may be any identifier (including one declared as a
1161  *  type), a reserved word storage class specifier, type specifier or
1162  *  type qualifier.  ??? This still leaves out most reserved keywords
1163  *  (following the old parser), shouldn't we include them, and why not
1164  *  allow identifiers declared as types to start the arguments?
1165  *
1166  *  Matze: this all looks confusing and little systematic, so we're even less
1167  *  strict and parse any list of things which are identifiers or
1168  *  (assignment-)expressions.
1169  */
1170 static attribute_argument_t *parse_attribute_arguments(void)
1171 {
1172         attribute_argument_t  *first  = NULL;
1173         attribute_argument_t **anchor = &first;
1174         if (token.type != ')') do {
1175                 attribute_argument_t *argument = allocate_ast_zero(sizeof(*argument));
1176
1177                 /* is it an identifier */
1178                 if (token.type == T_IDENTIFIER
1179                                 && (look_ahead(1)->type == ',' || look_ahead(1)->type == ')')) {
1180                         symbol_t *symbol   = token.symbol;
1181                         argument->kind     = ATTRIBUTE_ARGUMENT_SYMBOL;
1182                         argument->v.symbol = symbol;
1183                         next_token();
1184                 } else {
1185                         /* must be an expression */
1186                         expression_t *expression = parse_assignment_expression();
1187
1188                         argument->kind         = ATTRIBUTE_ARGUMENT_EXPRESSION;
1189                         argument->v.expression = expression;
1190                 }
1191
1192                 /* append argument */
1193                 *anchor = argument;
1194                 anchor  = &argument->next;
1195         } while (next_if(','));
1196         expect(')', end_error);
1197
1198         return first;
1199
1200 end_error:
1201         /* TODO... */
1202         return first;
1203 }
1204
1205 static attribute_t *parse_attribute_asm(void)
1206 {
1207         eat(T_asm);
1208
1209         attribute_t *attribute = allocate_attribute_zero(ATTRIBUTE_GNU_ASM);
1210
1211         expect('(', end_error);
1212         attribute->a.arguments = parse_attribute_arguments();
1213         return attribute;
1214
1215 end_error:
1216         return NULL;
1217 }
1218
1219 static symbol_t *get_symbol_from_token(void)
1220 {
1221         switch(token.type) {
1222         case T_IDENTIFIER:
1223                 return token.symbol;
1224         case T_auto:
1225         case T_char:
1226         case T_double:
1227         case T_enum:
1228         case T_extern:
1229         case T_float:
1230         case T_int:
1231         case T_long:
1232         case T_register:
1233         case T_short:
1234         case T_static:
1235         case T_struct:
1236         case T_union:
1237         case T_unsigned:
1238         case T_void:
1239         case T_bool:
1240         case T__Bool:
1241         case T_class:
1242         case T_explicit:
1243         case T_export:
1244         case T_wchar_t:
1245         case T_const:
1246         case T_signed:
1247         case T___real__:
1248         case T___imag__:
1249         case T_restrict:
1250         case T_volatile:
1251         case T_inline:
1252                 /* maybe we need more tokens ... add them on demand */
1253                 return get_token_symbol(&token);
1254         default:
1255                 return NULL;
1256         }
1257 }
1258
1259 static attribute_t *parse_attribute_gnu_single(void)
1260 {
1261         /* parse "any-word" */
1262         symbol_t *symbol = get_symbol_from_token();
1263         if (symbol == NULL) {
1264                 parse_error_expected("while parsing attribute((", T_IDENTIFIER, NULL);
1265                 return NULL;
1266         }
1267
1268         attribute_kind_t  kind;
1269         char const *const name = symbol->string;
1270         for (kind = ATTRIBUTE_GNU_FIRST;; ++kind) {
1271                 if (kind > ATTRIBUTE_GNU_LAST) {
1272                         if (warning.attribute) {
1273                                 warningf(HERE, "unknown attribute '%s' ignored", name);
1274                         }
1275                         /* TODO: we should still save the attribute in the list... */
1276                         kind = ATTRIBUTE_UNKNOWN;
1277                         break;
1278                 }
1279
1280                 const char *attribute_name = get_attribute_name(kind);
1281                 if (attribute_name != NULL
1282                                 && strcmp_underscore(attribute_name, name) == 0)
1283                         break;
1284         }
1285
1286         next_token();
1287
1288         attribute_t *attribute = allocate_attribute_zero(kind);
1289
1290         /* parse arguments */
1291         if (next_if('('))
1292                 attribute->a.arguments = parse_attribute_arguments();
1293
1294         return attribute;
1295 }
1296
1297 static attribute_t *parse_attribute_gnu(void)
1298 {
1299         attribute_t  *first  = NULL;
1300         attribute_t **anchor = &first;
1301
1302         eat(T___attribute__);
1303         expect('(', end_error);
1304         expect('(', end_error);
1305
1306         if (token.type != ')') do {
1307                 attribute_t *attribute = parse_attribute_gnu_single();
1308                 if (attribute == NULL)
1309                         goto end_error;
1310
1311                 *anchor = attribute;
1312                 anchor  = &attribute->next;
1313         } while (next_if(','));
1314         expect(')', end_error);
1315         expect(')', end_error);
1316
1317 end_error:
1318         return first;
1319 }
1320
1321 /** Parse attributes. */
1322 static attribute_t *parse_attributes(attribute_t *first)
1323 {
1324         attribute_t **anchor = &first;
1325         for (;;) {
1326                 while (*anchor != NULL)
1327                         anchor = &(*anchor)->next;
1328
1329                 attribute_t *attribute;
1330                 switch (token.type) {
1331                 case T___attribute__:
1332                         attribute = parse_attribute_gnu();
1333                         if (attribute == NULL)
1334                                 continue;
1335                         break;
1336
1337                 case T_asm:
1338                         attribute = parse_attribute_asm();
1339                         break;
1340
1341                 case T_cdecl:
1342                         next_token();
1343                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_CDECL);
1344                         break;
1345
1346                 case T__fastcall:
1347                         next_token();
1348                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_FASTCALL);
1349                         break;
1350
1351                 case T__forceinline:
1352                         next_token();
1353                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_FORCEINLINE);
1354                         break;
1355
1356                 case T__stdcall:
1357                         next_token();
1358                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_STDCALL);
1359                         break;
1360
1361                 case T___thiscall:
1362                         /* TODO record modifier */
1363                         if (warning.other)
1364                                 warningf(HERE, "Ignoring declaration modifier %K", &token);
1365                         eat(T___thiscall);
1366                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_THISCALL);
1367                         break;
1368
1369                 default:
1370                         return first;
1371                 }
1372
1373                 *anchor = attribute;
1374                 anchor  = &attribute->next;
1375         }
1376 }
1377
1378 static void mark_vars_read(expression_t *expr, entity_t *lhs_ent);
1379
1380 static entity_t *determine_lhs_ent(expression_t *const expr,
1381                                    entity_t *lhs_ent)
1382 {
1383         switch (expr->kind) {
1384                 case EXPR_REFERENCE: {
1385                         entity_t *const entity = expr->reference.entity;
1386                         /* we should only find variables as lvalues... */
1387                         if (entity->base.kind != ENTITY_VARIABLE
1388                                         && entity->base.kind != ENTITY_PARAMETER)
1389                                 return NULL;
1390
1391                         return entity;
1392                 }
1393
1394                 case EXPR_ARRAY_ACCESS: {
1395                         expression_t *const ref = expr->array_access.array_ref;
1396                         entity_t     *      ent = NULL;
1397                         if (is_type_array(skip_typeref(revert_automatic_type_conversion(ref)))) {
1398                                 ent     = determine_lhs_ent(ref, lhs_ent);
1399                                 lhs_ent = ent;
1400                         } else {
1401                                 mark_vars_read(expr->select.compound, lhs_ent);
1402                         }
1403                         mark_vars_read(expr->array_access.index, lhs_ent);
1404                         return ent;
1405                 }
1406
1407                 case EXPR_SELECT: {
1408                         if (is_type_compound(skip_typeref(expr->base.type))) {
1409                                 return determine_lhs_ent(expr->select.compound, lhs_ent);
1410                         } else {
1411                                 mark_vars_read(expr->select.compound, lhs_ent);
1412                                 return NULL;
1413                         }
1414                 }
1415
1416                 case EXPR_UNARY_DEREFERENCE: {
1417                         expression_t *const val = expr->unary.value;
1418                         if (val->kind == EXPR_UNARY_TAKE_ADDRESS) {
1419                                 /* *&x is a NOP */
1420                                 return determine_lhs_ent(val->unary.value, lhs_ent);
1421                         } else {
1422                                 mark_vars_read(val, NULL);
1423                                 return NULL;
1424                         }
1425                 }
1426
1427                 default:
1428                         mark_vars_read(expr, NULL);
1429                         return NULL;
1430         }
1431 }
1432
1433 #define ENT_ANY ((entity_t*)-1)
1434
1435 /**
1436  * Mark declarations, which are read.  This is used to detect variables, which
1437  * are never read.
1438  * Example:
1439  * x = x + 1;
1440  *   x is not marked as "read", because it is only read to calculate its own new
1441  *   value.
1442  *
1443  * x += y; y += x;
1444  *   x and y are not detected as "not read", because multiple variables are
1445  *   involved.
1446  */
1447 static void mark_vars_read(expression_t *const expr, entity_t *lhs_ent)
1448 {
1449         switch (expr->kind) {
1450                 case EXPR_REFERENCE: {
1451                         entity_t *const entity = expr->reference.entity;
1452                         if (entity->kind != ENTITY_VARIABLE
1453                                         && entity->kind != ENTITY_PARAMETER)
1454                                 return;
1455
1456                         if (lhs_ent != entity && lhs_ent != ENT_ANY) {
1457                                 if (entity->kind == ENTITY_VARIABLE) {
1458                                         entity->variable.read = true;
1459                                 } else {
1460                                         entity->parameter.read = true;
1461                                 }
1462                         }
1463                         return;
1464                 }
1465
1466                 case EXPR_CALL:
1467                         // TODO respect pure/const
1468                         mark_vars_read(expr->call.function, NULL);
1469                         for (call_argument_t *arg = expr->call.arguments; arg != NULL; arg = arg->next) {
1470                                 mark_vars_read(arg->expression, NULL);
1471                         }
1472                         return;
1473
1474                 case EXPR_CONDITIONAL:
1475                         // TODO lhs_decl should depend on whether true/false have an effect
1476                         mark_vars_read(expr->conditional.condition, NULL);
1477                         if (expr->conditional.true_expression != NULL)
1478                                 mark_vars_read(expr->conditional.true_expression, lhs_ent);
1479                         mark_vars_read(expr->conditional.false_expression, lhs_ent);
1480                         return;
1481
1482                 case EXPR_SELECT:
1483                         if (lhs_ent == ENT_ANY
1484                                         && !is_type_compound(skip_typeref(expr->base.type)))
1485                                 lhs_ent = NULL;
1486                         mark_vars_read(expr->select.compound, lhs_ent);
1487                         return;
1488
1489                 case EXPR_ARRAY_ACCESS: {
1490                         expression_t *const ref = expr->array_access.array_ref;
1491                         mark_vars_read(ref, lhs_ent);
1492                         lhs_ent = determine_lhs_ent(ref, lhs_ent);
1493                         mark_vars_read(expr->array_access.index, lhs_ent);
1494                         return;
1495                 }
1496
1497                 case EXPR_VA_ARG:
1498                         mark_vars_read(expr->va_arge.ap, lhs_ent);
1499                         return;
1500
1501                 case EXPR_VA_COPY:
1502                         mark_vars_read(expr->va_copye.src, lhs_ent);
1503                         return;
1504
1505                 case EXPR_UNARY_CAST:
1506                         /* Special case: Use void cast to mark a variable as "read" */
1507                         if (is_type_atomic(skip_typeref(expr->base.type), ATOMIC_TYPE_VOID))
1508                                 lhs_ent = NULL;
1509                         goto unary;
1510
1511
1512                 case EXPR_UNARY_THROW:
1513                         if (expr->unary.value == NULL)
1514                                 return;
1515                         /* FALLTHROUGH */
1516                 case EXPR_UNARY_DEREFERENCE:
1517                 case EXPR_UNARY_DELETE:
1518                 case EXPR_UNARY_DELETE_ARRAY:
1519                         if (lhs_ent == ENT_ANY)
1520                                 lhs_ent = NULL;
1521                         goto unary;
1522
1523                 case EXPR_UNARY_NEGATE:
1524                 case EXPR_UNARY_PLUS:
1525                 case EXPR_UNARY_BITWISE_NEGATE:
1526                 case EXPR_UNARY_NOT:
1527                 case EXPR_UNARY_TAKE_ADDRESS:
1528                 case EXPR_UNARY_POSTFIX_INCREMENT:
1529                 case EXPR_UNARY_POSTFIX_DECREMENT:
1530                 case EXPR_UNARY_PREFIX_INCREMENT:
1531                 case EXPR_UNARY_PREFIX_DECREMENT:
1532                 case EXPR_UNARY_CAST_IMPLICIT:
1533                 case EXPR_UNARY_ASSUME:
1534 unary:
1535                         mark_vars_read(expr->unary.value, lhs_ent);
1536                         return;
1537
1538                 case EXPR_BINARY_ADD:
1539                 case EXPR_BINARY_SUB:
1540                 case EXPR_BINARY_MUL:
1541                 case EXPR_BINARY_DIV:
1542                 case EXPR_BINARY_MOD:
1543                 case EXPR_BINARY_EQUAL:
1544                 case EXPR_BINARY_NOTEQUAL:
1545                 case EXPR_BINARY_LESS:
1546                 case EXPR_BINARY_LESSEQUAL:
1547                 case EXPR_BINARY_GREATER:
1548                 case EXPR_BINARY_GREATEREQUAL:
1549                 case EXPR_BINARY_BITWISE_AND:
1550                 case EXPR_BINARY_BITWISE_OR:
1551                 case EXPR_BINARY_BITWISE_XOR:
1552                 case EXPR_BINARY_LOGICAL_AND:
1553                 case EXPR_BINARY_LOGICAL_OR:
1554                 case EXPR_BINARY_SHIFTLEFT:
1555                 case EXPR_BINARY_SHIFTRIGHT:
1556                 case EXPR_BINARY_COMMA:
1557                 case EXPR_BINARY_ISGREATER:
1558                 case EXPR_BINARY_ISGREATEREQUAL:
1559                 case EXPR_BINARY_ISLESS:
1560                 case EXPR_BINARY_ISLESSEQUAL:
1561                 case EXPR_BINARY_ISLESSGREATER:
1562                 case EXPR_BINARY_ISUNORDERED:
1563                         mark_vars_read(expr->binary.left,  lhs_ent);
1564                         mark_vars_read(expr->binary.right, lhs_ent);
1565                         return;
1566
1567                 case EXPR_BINARY_ASSIGN:
1568                 case EXPR_BINARY_MUL_ASSIGN:
1569                 case EXPR_BINARY_DIV_ASSIGN:
1570                 case EXPR_BINARY_MOD_ASSIGN:
1571                 case EXPR_BINARY_ADD_ASSIGN:
1572                 case EXPR_BINARY_SUB_ASSIGN:
1573                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:
1574                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
1575                 case EXPR_BINARY_BITWISE_AND_ASSIGN:
1576                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:
1577                 case EXPR_BINARY_BITWISE_OR_ASSIGN: {
1578                         if (lhs_ent == ENT_ANY)
1579                                 lhs_ent = NULL;
1580                         lhs_ent = determine_lhs_ent(expr->binary.left, lhs_ent);
1581                         mark_vars_read(expr->binary.right, lhs_ent);
1582                         return;
1583                 }
1584
1585                 case EXPR_VA_START:
1586                         determine_lhs_ent(expr->va_starte.ap, lhs_ent);
1587                         return;
1588
1589                 EXPR_LITERAL_CASES
1590                 case EXPR_UNKNOWN:
1591                 case EXPR_INVALID:
1592                 case EXPR_STRING_LITERAL:
1593                 case EXPR_WIDE_STRING_LITERAL:
1594                 case EXPR_COMPOUND_LITERAL: // TODO init?
1595                 case EXPR_SIZEOF:
1596                 case EXPR_CLASSIFY_TYPE:
1597                 case EXPR_ALIGNOF:
1598                 case EXPR_FUNCNAME:
1599                 case EXPR_BUILTIN_CONSTANT_P:
1600                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P:
1601                 case EXPR_OFFSETOF:
1602                 case EXPR_STATEMENT: // TODO
1603                 case EXPR_LABEL_ADDRESS:
1604                 case EXPR_REFERENCE_ENUM_VALUE:
1605                         return;
1606         }
1607
1608         panic("unhandled expression");
1609 }
1610
1611 static designator_t *parse_designation(void)
1612 {
1613         designator_t  *result = NULL;
1614         designator_t **anchor = &result;
1615
1616         for (;;) {
1617                 designator_t *designator;
1618                 switch (token.type) {
1619                 case '[':
1620                         designator = allocate_ast_zero(sizeof(designator[0]));
1621                         designator->source_position = token.source_position;
1622                         next_token();
1623                         add_anchor_token(']');
1624                         designator->array_index = parse_constant_expression();
1625                         rem_anchor_token(']');
1626                         expect(']', end_error);
1627                         break;
1628                 case '.':
1629                         designator = allocate_ast_zero(sizeof(designator[0]));
1630                         designator->source_position = token.source_position;
1631                         next_token();
1632                         if (token.type != T_IDENTIFIER) {
1633                                 parse_error_expected("while parsing designator",
1634                                                      T_IDENTIFIER, NULL);
1635                                 return NULL;
1636                         }
1637                         designator->symbol = token.symbol;
1638                         next_token();
1639                         break;
1640                 default:
1641                         expect('=', end_error);
1642                         return result;
1643                 }
1644
1645                 assert(designator != NULL);
1646                 *anchor = designator;
1647                 anchor  = &designator->next;
1648         }
1649 end_error:
1650         return NULL;
1651 }
1652
1653 static initializer_t *initializer_from_string(array_type_t *const type,
1654                                               const string_t *const string)
1655 {
1656         /* TODO: check len vs. size of array type */
1657         (void) type;
1658
1659         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
1660         initializer->string.string = *string;
1661
1662         return initializer;
1663 }
1664
1665 static initializer_t *initializer_from_wide_string(array_type_t *const type,
1666                                                    const string_t *const string)
1667 {
1668         /* TODO: check len vs. size of array type */
1669         (void) type;
1670
1671         initializer_t *const initializer =
1672                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
1673         initializer->wide_string.string = *string;
1674
1675         return initializer;
1676 }
1677
1678 /**
1679  * Build an initializer from a given expression.
1680  */
1681 static initializer_t *initializer_from_expression(type_t *orig_type,
1682                                                   expression_t *expression)
1683 {
1684         /* TODO check that expression is a constant expression */
1685
1686         /* §6.7.8.14/15 char array may be initialized by string literals */
1687         type_t *type           = skip_typeref(orig_type);
1688         type_t *expr_type_orig = expression->base.type;
1689         type_t *expr_type      = skip_typeref(expr_type_orig);
1690
1691         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
1692                 array_type_t *const array_type   = &type->array;
1693                 type_t       *const element_type = skip_typeref(array_type->element_type);
1694
1695                 if (element_type->kind == TYPE_ATOMIC) {
1696                         atomic_type_kind_t akind = element_type->atomic.akind;
1697                         switch (expression->kind) {
1698                         case EXPR_STRING_LITERAL:
1699                                 if (akind == ATOMIC_TYPE_CHAR
1700                                                 || akind == ATOMIC_TYPE_SCHAR
1701                                                 || akind == ATOMIC_TYPE_UCHAR) {
1702                                         return initializer_from_string(array_type,
1703                                                         &expression->string_literal.value);
1704                                 }
1705                                 break;
1706
1707                         case EXPR_WIDE_STRING_LITERAL: {
1708                                 type_t *bare_wchar_type = skip_typeref(type_wchar_t);
1709                                 if (get_unqualified_type(element_type) == bare_wchar_type) {
1710                                         return initializer_from_wide_string(array_type,
1711                                                         &expression->string_literal.value);
1712                                 }
1713                                 break;
1714                         }
1715
1716                         default:
1717                                 break;
1718                         }
1719                 }
1720         }
1721
1722         assign_error_t error = semantic_assign(type, expression);
1723         if (error == ASSIGN_ERROR_INCOMPATIBLE)
1724                 return NULL;
1725         report_assign_error(error, type, expression, "initializer",
1726                             &expression->base.source_position);
1727
1728         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
1729         result->value.value = create_implicit_cast(expression, type);
1730
1731         return result;
1732 }
1733
1734 /**
1735  * Checks if a given expression can be used as an constant initializer.
1736  */
1737 static bool is_initializer_constant(const expression_t *expression)
1738 {
1739         return
1740                 is_constant_expression(expression) != EXPR_CLASS_VARIABLE ||
1741                 is_address_constant(expression)    != EXPR_CLASS_VARIABLE;
1742 }
1743
1744 /**
1745  * Parses an scalar initializer.
1746  *
1747  * §6.7.8.11; eat {} without warning
1748  */
1749 static initializer_t *parse_scalar_initializer(type_t *type,
1750                                                bool must_be_constant)
1751 {
1752         /* there might be extra {} hierarchies */
1753         int braces = 0;
1754         if (token.type == '{') {
1755                 if (warning.other)
1756                         warningf(HERE, "extra curly braces around scalar initializer");
1757                 do {
1758                         eat('{');
1759                         ++braces;
1760                 } while (token.type == '{');
1761         }
1762
1763         expression_t *expression = parse_assignment_expression();
1764         mark_vars_read(expression, NULL);
1765         if (must_be_constant && !is_initializer_constant(expression)) {
1766                 errorf(&expression->base.source_position,
1767                        "initialisation expression '%E' is not constant",
1768                        expression);
1769         }
1770
1771         initializer_t *initializer = initializer_from_expression(type, expression);
1772
1773         if (initializer == NULL) {
1774                 errorf(&expression->base.source_position,
1775                        "expression '%E' (type '%T') doesn't match expected type '%T'",
1776                        expression, expression->base.type, type);
1777                 /* TODO */
1778                 return NULL;
1779         }
1780
1781         bool additional_warning_displayed = false;
1782         while (braces > 0) {
1783                 next_if(',');
1784                 if (token.type != '}') {
1785                         if (!additional_warning_displayed && warning.other) {
1786                                 warningf(HERE, "additional elements in scalar initializer");
1787                                 additional_warning_displayed = true;
1788                         }
1789                 }
1790                 eat_block();
1791                 braces--;
1792         }
1793
1794         return initializer;
1795 }
1796
1797 /**
1798  * An entry in the type path.
1799  */
1800 typedef struct type_path_entry_t type_path_entry_t;
1801 struct type_path_entry_t {
1802         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
1803         union {
1804                 size_t         index;          /**< For array types: the current index. */
1805                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
1806         } v;
1807 };
1808
1809 /**
1810  * A type path expression a position inside compound or array types.
1811  */
1812 typedef struct type_path_t type_path_t;
1813 struct type_path_t {
1814         type_path_entry_t *path;         /**< An flexible array containing the current path. */
1815         type_t            *top_type;     /**< type of the element the path points */
1816         size_t             max_index;    /**< largest index in outermost array */
1817 };
1818
1819 /**
1820  * Prints a type path for debugging.
1821  */
1822 static __attribute__((unused)) void debug_print_type_path(
1823                 const type_path_t *path)
1824 {
1825         size_t len = ARR_LEN(path->path);
1826
1827         for (size_t i = 0; i < len; ++i) {
1828                 const type_path_entry_t *entry = & path->path[i];
1829
1830                 type_t *type = skip_typeref(entry->type);
1831                 if (is_type_compound(type)) {
1832                         /* in gcc mode structs can have no members */
1833                         if (entry->v.compound_entry == NULL) {
1834                                 assert(i == len-1);
1835                                 continue;
1836                         }
1837                         fprintf(stderr, ".%s",
1838                                 entry->v.compound_entry->base.symbol->string);
1839                 } else if (is_type_array(type)) {
1840                         fprintf(stderr, "[%u]", (unsigned) entry->v.index);
1841                 } else {
1842                         fprintf(stderr, "-INVALID-");
1843                 }
1844         }
1845         if (path->top_type != NULL) {
1846                 fprintf(stderr, "  (");
1847                 print_type(path->top_type);
1848                 fprintf(stderr, ")");
1849         }
1850 }
1851
1852 /**
1853  * Return the top type path entry, ie. in a path
1854  * (type).a.b returns the b.
1855  */
1856 static type_path_entry_t *get_type_path_top(const type_path_t *path)
1857 {
1858         size_t len = ARR_LEN(path->path);
1859         assert(len > 0);
1860         return &path->path[len-1];
1861 }
1862
1863 /**
1864  * Enlarge the type path by an (empty) element.
1865  */
1866 static type_path_entry_t *append_to_type_path(type_path_t *path)
1867 {
1868         size_t len = ARR_LEN(path->path);
1869         ARR_RESIZE(type_path_entry_t, path->path, len+1);
1870
1871         type_path_entry_t *result = & path->path[len];
1872         memset(result, 0, sizeof(result[0]));
1873         return result;
1874 }
1875
1876 /**
1877  * Descending into a sub-type. Enter the scope of the current top_type.
1878  */
1879 static void descend_into_subtype(type_path_t *path)
1880 {
1881         type_t *orig_top_type = path->top_type;
1882         type_t *top_type      = skip_typeref(orig_top_type);
1883
1884         type_path_entry_t *top = append_to_type_path(path);
1885         top->type              = top_type;
1886
1887         if (is_type_compound(top_type)) {
1888                 compound_t *compound  = top_type->compound.compound;
1889                 entity_t   *entry     = compound->members.entities;
1890
1891                 if (entry != NULL) {
1892                         assert(entry->kind == ENTITY_COMPOUND_MEMBER);
1893                         top->v.compound_entry = &entry->declaration;
1894                         path->top_type = entry->declaration.type;
1895                 } else {
1896                         path->top_type = NULL;
1897                 }
1898         } else if (is_type_array(top_type)) {
1899                 top->v.index   = 0;
1900                 path->top_type = top_type->array.element_type;
1901         } else {
1902                 assert(!is_type_valid(top_type));
1903         }
1904 }
1905
1906 /**
1907  * Pop an entry from the given type path, ie. returning from
1908  * (type).a.b to (type).a
1909  */
1910 static void ascend_from_subtype(type_path_t *path)
1911 {
1912         type_path_entry_t *top = get_type_path_top(path);
1913
1914         path->top_type = top->type;
1915
1916         size_t len = ARR_LEN(path->path);
1917         ARR_RESIZE(type_path_entry_t, path->path, len-1);
1918 }
1919
1920 /**
1921  * Pop entries from the given type path until the given
1922  * path level is reached.
1923  */
1924 static void ascend_to(type_path_t *path, size_t top_path_level)
1925 {
1926         size_t len = ARR_LEN(path->path);
1927
1928         while (len > top_path_level) {
1929                 ascend_from_subtype(path);
1930                 len = ARR_LEN(path->path);
1931         }
1932 }
1933
1934 static bool walk_designator(type_path_t *path, const designator_t *designator,
1935                             bool used_in_offsetof)
1936 {
1937         for (; designator != NULL; designator = designator->next) {
1938                 type_path_entry_t *top       = get_type_path_top(path);
1939                 type_t            *orig_type = top->type;
1940
1941                 type_t *type = skip_typeref(orig_type);
1942
1943                 if (designator->symbol != NULL) {
1944                         symbol_t *symbol = designator->symbol;
1945                         if (!is_type_compound(type)) {
1946                                 if (is_type_valid(type)) {
1947                                         errorf(&designator->source_position,
1948                                                "'.%Y' designator used for non-compound type '%T'",
1949                                                symbol, orig_type);
1950                                 }
1951
1952                                 top->type             = type_error_type;
1953                                 top->v.compound_entry = NULL;
1954                                 orig_type             = type_error_type;
1955                         } else {
1956                                 compound_t *compound = type->compound.compound;
1957                                 entity_t   *iter     = compound->members.entities;
1958                                 for (; iter != NULL; iter = iter->base.next) {
1959                                         if (iter->base.symbol == symbol) {
1960                                                 break;
1961                                         }
1962                                 }
1963                                 if (iter == NULL) {
1964                                         errorf(&designator->source_position,
1965                                                "'%T' has no member named '%Y'", orig_type, symbol);
1966                                         return false;
1967                                 }
1968                                 assert(iter->kind == ENTITY_COMPOUND_MEMBER);
1969                                 if (used_in_offsetof) {
1970                                         type_t *real_type = skip_typeref(iter->declaration.type);
1971                                         if (real_type->kind == TYPE_BITFIELD) {
1972                                                 errorf(&designator->source_position,
1973                                                        "offsetof designator '%Y' must not specify bitfield",
1974                                                        symbol);
1975                                                 return false;
1976                                         }
1977                                 }
1978
1979                                 top->type             = orig_type;
1980                                 top->v.compound_entry = &iter->declaration;
1981                                 orig_type             = iter->declaration.type;
1982                         }
1983                 } else {
1984                         expression_t *array_index = designator->array_index;
1985                         assert(designator->array_index != NULL);
1986
1987                         if (!is_type_array(type)) {
1988                                 if (is_type_valid(type)) {
1989                                         errorf(&designator->source_position,
1990                                                "[%E] designator used for non-array type '%T'",
1991                                                array_index, orig_type);
1992                                 }
1993                                 return false;
1994                         }
1995
1996                         long index = fold_constant_to_int(array_index);
1997                         if (!used_in_offsetof) {
1998                                 if (index < 0) {
1999                                         errorf(&designator->source_position,
2000                                                "array index [%E] must be positive", array_index);
2001                                 } else if (type->array.size_constant) {
2002                                         long array_size = type->array.size;
2003                                         if (index >= array_size) {
2004                                                 errorf(&designator->source_position,
2005                                                        "designator [%E] (%d) exceeds array size %d",
2006                                                        array_index, index, array_size);
2007                                         }
2008                                 }
2009                         }
2010
2011                         top->type    = orig_type;
2012                         top->v.index = (size_t) index;
2013                         orig_type    = type->array.element_type;
2014                 }
2015                 path->top_type = orig_type;
2016
2017                 if (designator->next != NULL) {
2018                         descend_into_subtype(path);
2019                 }
2020         }
2021         return true;
2022 }
2023
2024 static void advance_current_object(type_path_t *path, size_t top_path_level)
2025 {
2026         type_path_entry_t *top = get_type_path_top(path);
2027
2028         type_t *type = skip_typeref(top->type);
2029         if (is_type_union(type)) {
2030                 /* in unions only the first element is initialized */
2031                 top->v.compound_entry = NULL;
2032         } else if (is_type_struct(type)) {
2033                 declaration_t *entry = top->v.compound_entry;
2034
2035                 entity_t *next_entity = entry->base.next;
2036                 if (next_entity != NULL) {
2037                         assert(is_declaration(next_entity));
2038                         entry = &next_entity->declaration;
2039                 } else {
2040                         entry = NULL;
2041                 }
2042
2043                 top->v.compound_entry = entry;
2044                 if (entry != NULL) {
2045                         path->top_type = entry->type;
2046                         return;
2047                 }
2048         } else if (is_type_array(type)) {
2049                 assert(is_type_array(type));
2050
2051                 top->v.index++;
2052
2053                 if (!type->array.size_constant || top->v.index < type->array.size) {
2054                         return;
2055                 }
2056         } else {
2057                 assert(!is_type_valid(type));
2058                 return;
2059         }
2060
2061         /* we're past the last member of the current sub-aggregate, try if we
2062          * can ascend in the type hierarchy and continue with another subobject */
2063         size_t len = ARR_LEN(path->path);
2064
2065         if (len > top_path_level) {
2066                 ascend_from_subtype(path);
2067                 advance_current_object(path, top_path_level);
2068         } else {
2069                 path->top_type = NULL;
2070         }
2071 }
2072
2073 /**
2074  * skip any {...} blocks until a closing bracket is reached.
2075  */
2076 static void skip_initializers(void)
2077 {
2078         next_if('{');
2079
2080         while (token.type != '}') {
2081                 if (token.type == T_EOF)
2082                         return;
2083                 if (token.type == '{') {
2084                         eat_block();
2085                         continue;
2086                 }
2087                 next_token();
2088         }
2089 }
2090
2091 static initializer_t *create_empty_initializer(void)
2092 {
2093         static initializer_t empty_initializer
2094                 = { .list = { { INITIALIZER_LIST }, 0 } };
2095         return &empty_initializer;
2096 }
2097
2098 /**
2099  * Parse a part of an initialiser for a struct or union,
2100  */
2101 static initializer_t *parse_sub_initializer(type_path_t *path,
2102                 type_t *outer_type, size_t top_path_level,
2103                 parse_initializer_env_t *env)
2104 {
2105         if (token.type == '}') {
2106                 /* empty initializer */
2107                 return create_empty_initializer();
2108         }
2109
2110         type_t *orig_type = path->top_type;
2111         type_t *type      = NULL;
2112
2113         if (orig_type == NULL) {
2114                 /* We are initializing an empty compound. */
2115         } else {
2116                 type = skip_typeref(orig_type);
2117         }
2118
2119         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2120
2121         while (true) {
2122                 designator_t *designator = NULL;
2123                 if (token.type == '.' || token.type == '[') {
2124                         designator = parse_designation();
2125                         goto finish_designator;
2126                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2127                         /* GNU-style designator ("identifier: value") */
2128                         designator = allocate_ast_zero(sizeof(designator[0]));
2129                         designator->source_position = token.source_position;
2130                         designator->symbol          = token.symbol;
2131                         eat(T_IDENTIFIER);
2132                         eat(':');
2133
2134 finish_designator:
2135                         /* reset path to toplevel, evaluate designator from there */
2136                         ascend_to(path, top_path_level);
2137                         if (!walk_designator(path, designator, false)) {
2138                                 /* can't continue after designation error */
2139                                 goto end_error;
2140                         }
2141
2142                         initializer_t *designator_initializer
2143                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2144                         designator_initializer->designator.designator = designator;
2145                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2146
2147                         orig_type = path->top_type;
2148                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2149                 }
2150
2151                 initializer_t *sub;
2152
2153                 if (token.type == '{') {
2154                         if (type != NULL && is_type_scalar(type)) {
2155                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2156                         } else {
2157                                 if (type == NULL) {
2158                                         if (env->entity != NULL) {
2159                                                 errorf(HERE,
2160                                                      "extra brace group at end of initializer for '%Y'",
2161                                                      env->entity->base.symbol);
2162                                         } else {
2163                                                 errorf(HERE, "extra brace group at end of initializer");
2164                                         }
2165                                         eat('{');
2166                                 } else {
2167                                         eat('{');
2168                                         descend_into_subtype(path);
2169                                 }
2170
2171                                 add_anchor_token('}');
2172                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2173                                                             env);
2174                                 rem_anchor_token('}');
2175
2176                                 if (type != NULL) {
2177                                         ascend_from_subtype(path);
2178                                         expect('}', end_error);
2179                                 } else {
2180                                         expect('}', end_error);
2181                                         goto error_parse_next;
2182                                 }
2183                         }
2184                 } else {
2185                         /* must be an expression */
2186                         expression_t *expression = parse_assignment_expression();
2187                         mark_vars_read(expression, NULL);
2188
2189                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2190                                 errorf(&expression->base.source_position,
2191                                        "Initialisation expression '%E' is not constant",
2192                                        expression);
2193                         }
2194
2195                         if (type == NULL) {
2196                                 /* we are already outside, ... */
2197                                 if (outer_type == NULL)
2198                                         goto error_parse_next;
2199                                 type_t *const outer_type_skip = skip_typeref(outer_type);
2200                                 if (is_type_compound(outer_type_skip) &&
2201                                                 !outer_type_skip->compound.compound->complete) {
2202                                         goto error_parse_next;
2203                                 }
2204
2205                                 if (warning.other) {
2206                                         source_position_t const* const pos = &expression->base.source_position;
2207                                         if (env->entity != NULL) {
2208                                                 warningf(pos, "excess elements in initializer for '%Y'", env->entity->base.symbol);
2209                                         } else {
2210                                                 warningf(pos, "excess elements in initializer");
2211                                         }
2212                                 }
2213                                 goto error_parse_next;
2214                         }
2215
2216                         /* handle { "string" } special case */
2217                         if ((expression->kind == EXPR_STRING_LITERAL
2218                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2219                                         && outer_type != NULL) {
2220                                 sub = initializer_from_expression(outer_type, expression);
2221                                 if (sub != NULL) {
2222                                         next_if(',');
2223                                         if (token.type != '}' && warning.other) {
2224                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2225                                                                  orig_type);
2226                                         }
2227                                         /* TODO: eat , ... */
2228                                         return sub;
2229                                 }
2230                         }
2231
2232                         /* descend into subtypes until expression matches type */
2233                         while (true) {
2234                                 orig_type = path->top_type;
2235                                 type      = skip_typeref(orig_type);
2236
2237                                 sub = initializer_from_expression(orig_type, expression);
2238                                 if (sub != NULL) {
2239                                         break;
2240                                 }
2241                                 if (!is_type_valid(type)) {
2242                                         goto end_error;
2243                                 }
2244                                 if (is_type_scalar(type)) {
2245                                         errorf(&expression->base.source_position,
2246                                                         "expression '%E' doesn't match expected type '%T'",
2247                                                         expression, orig_type);
2248                                         goto end_error;
2249                                 }
2250
2251                                 descend_into_subtype(path);
2252                         }
2253                 }
2254
2255                 /* update largest index of top array */
2256                 const type_path_entry_t *first      = &path->path[0];
2257                 type_t                  *first_type = first->type;
2258                 first_type                          = skip_typeref(first_type);
2259                 if (is_type_array(first_type)) {
2260                         size_t index = first->v.index;
2261                         if (index > path->max_index)
2262                                 path->max_index = index;
2263                 }
2264
2265                 /* append to initializers list */
2266                 ARR_APP1(initializer_t*, initializers, sub);
2267
2268 error_parse_next:
2269                 if (token.type == '}') {
2270                         break;
2271                 }
2272                 expect(',', end_error);
2273                 if (token.type == '}') {
2274                         break;
2275                 }
2276
2277                 if (type != NULL) {
2278                         /* advance to the next declaration if we are not at the end */
2279                         advance_current_object(path, top_path_level);
2280                         orig_type = path->top_type;
2281                         if (orig_type != NULL)
2282                                 type = skip_typeref(orig_type);
2283                         else
2284                                 type = NULL;
2285                 }
2286         }
2287
2288         size_t len  = ARR_LEN(initializers);
2289         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2290         initializer_t *result = allocate_ast_zero(size);
2291         result->kind          = INITIALIZER_LIST;
2292         result->list.len      = len;
2293         memcpy(&result->list.initializers, initializers,
2294                len * sizeof(initializers[0]));
2295
2296         DEL_ARR_F(initializers);
2297         ascend_to(path, top_path_level+1);
2298
2299         return result;
2300
2301 end_error:
2302         skip_initializers();
2303         DEL_ARR_F(initializers);
2304         ascend_to(path, top_path_level+1);
2305         return NULL;
2306 }
2307
2308 static expression_t *make_size_literal(size_t value)
2309 {
2310         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_INTEGER);
2311         literal->base.type    = type_size_t;
2312
2313         char buf[128];
2314         snprintf(buf, sizeof(buf), "%u", (unsigned) value);
2315         literal->literal.value = make_string(buf);
2316
2317         return literal;
2318 }
2319
2320 /**
2321  * Parses an initializer. Parsers either a compound literal
2322  * (env->declaration == NULL) or an initializer of a declaration.
2323  */
2324 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2325 {
2326         type_t        *type      = skip_typeref(env->type);
2327         size_t         max_index = 0;
2328         initializer_t *result;
2329
2330         if (is_type_scalar(type)) {
2331                 result = parse_scalar_initializer(type, env->must_be_constant);
2332         } else if (token.type == '{') {
2333                 eat('{');
2334
2335                 type_path_t path;
2336                 memset(&path, 0, sizeof(path));
2337                 path.top_type = env->type;
2338                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2339
2340                 descend_into_subtype(&path);
2341
2342                 add_anchor_token('}');
2343                 result = parse_sub_initializer(&path, env->type, 1, env);
2344                 rem_anchor_token('}');
2345
2346                 max_index = path.max_index;
2347                 DEL_ARR_F(path.path);
2348
2349                 expect('}', end_error);
2350 end_error:;
2351         } else {
2352                 /* parse_scalar_initializer() also works in this case: we simply
2353                  * have an expression without {} around it */
2354                 result = parse_scalar_initializer(type, env->must_be_constant);
2355         }
2356
2357         /* §6.7.8:22 array initializers for arrays with unknown size determine
2358          * the array type size */
2359         if (is_type_array(type) && type->array.size_expression == NULL
2360                         && result != NULL) {
2361                 size_t size;
2362                 switch (result->kind) {
2363                 case INITIALIZER_LIST:
2364                         assert(max_index != 0xdeadbeaf);
2365                         size = max_index + 1;
2366                         break;
2367
2368                 case INITIALIZER_STRING:
2369                         size = result->string.string.size;
2370                         break;
2371
2372                 case INITIALIZER_WIDE_STRING:
2373                         size = result->wide_string.string.size;
2374                         break;
2375
2376                 case INITIALIZER_DESIGNATOR:
2377                 case INITIALIZER_VALUE:
2378                         /* can happen for parse errors */
2379                         size = 0;
2380                         break;
2381
2382                 default:
2383                         internal_errorf(HERE, "invalid initializer type");
2384                 }
2385
2386                 type_t *new_type = duplicate_type(type);
2387
2388                 new_type->array.size_expression   = make_size_literal(size);
2389                 new_type->array.size_constant     = true;
2390                 new_type->array.has_implicit_size = true;
2391                 new_type->array.size              = size;
2392                 env->type = new_type;
2393         }
2394
2395         return result;
2396 }
2397
2398 static void append_entity(scope_t *scope, entity_t *entity)
2399 {
2400         if (scope->last_entity != NULL) {
2401                 scope->last_entity->base.next = entity;
2402         } else {
2403                 scope->entities = entity;
2404         }
2405         entity->base.parent_entity = current_entity;
2406         scope->last_entity         = entity;
2407 }
2408
2409
2410 static compound_t *parse_compound_type_specifier(bool is_struct)
2411 {
2412         source_position_t const pos = *HERE;
2413         eat(is_struct ? T_struct : T_union);
2414
2415         symbol_t    *symbol     = NULL;
2416         entity_t    *entity     = NULL;
2417         attribute_t *attributes = NULL;
2418
2419         if (token.type == T___attribute__) {
2420                 attributes = parse_attributes(NULL);
2421         }
2422
2423         entity_kind_tag_t const kind = is_struct ? ENTITY_STRUCT : ENTITY_UNION;
2424         if (token.type == T_IDENTIFIER) {
2425                 /* the compound has a name, check if we have seen it already */
2426                 symbol = token.symbol;
2427                 entity = get_tag(symbol, kind);
2428                 next_token();
2429
2430                 if (entity != NULL) {
2431                         if (entity->base.parent_scope != current_scope &&
2432                             (token.type == '{' || token.type == ';')) {
2433                                 /* we're in an inner scope and have a definition. Shadow
2434                                  * existing definition in outer scope */
2435                                 entity = NULL;
2436                         } else if (entity->compound.complete && token.type == '{') {
2437                                 errorf(&pos, "multiple definitions of '%s %Y' (previous definition %P)",
2438                                        is_struct ? "struct" : "union", symbol,
2439                                        &entity->base.source_position);
2440                                 /* clear members in the hope to avoid further errors */
2441                                 entity->compound.members.entities = NULL;
2442                         }
2443                 }
2444         } else if (token.type != '{') {
2445                 char const *const msg =
2446                         is_struct ? "while parsing struct type specifier" :
2447                                     "while parsing union type specifier";
2448                 parse_error_expected(msg, T_IDENTIFIER, '{', NULL);
2449
2450                 return NULL;
2451         }
2452
2453         if (entity == NULL) {
2454                 entity = allocate_entity_zero(kind, NAMESPACE_TAG, symbol);
2455                 entity->compound.alignment   = 1;
2456                 entity->base.source_position = pos;
2457                 entity->base.parent_scope    = current_scope;
2458                 if (symbol != NULL) {
2459                         environment_push(entity);
2460                 }
2461                 append_entity(current_scope, entity);
2462         }
2463
2464         if (token.type == '{') {
2465                 parse_compound_type_entries(&entity->compound);
2466
2467                 /* ISO/IEC 14882:1998(E) §7.1.3:5 */
2468                 if (symbol == NULL) {
2469                         assert(anonymous_entity == NULL);
2470                         anonymous_entity = entity;
2471                 }
2472         }
2473
2474         if (attributes != NULL) {
2475                 handle_entity_attributes(attributes, entity);
2476         }
2477
2478         return &entity->compound;
2479 }
2480
2481 static void parse_enum_entries(type_t *const enum_type)
2482 {
2483         eat('{');
2484
2485         if (token.type == '}') {
2486                 errorf(HERE, "empty enum not allowed");
2487                 next_token();
2488                 return;
2489         }
2490
2491         add_anchor_token('}');
2492         do {
2493                 if (token.type != T_IDENTIFIER) {
2494                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
2495                         eat_block();
2496                         rem_anchor_token('}');
2497                         return;
2498                 }
2499
2500                 entity_t *const entity = allocate_entity_zero(ENTITY_ENUM_VALUE, NAMESPACE_NORMAL, token.symbol);
2501                 entity->enum_value.enum_type = enum_type;
2502                 entity->base.source_position = token.source_position;
2503                 next_token();
2504
2505                 if (next_if('=')) {
2506                         expression_t *value = parse_constant_expression();
2507
2508                         value = create_implicit_cast(value, enum_type);
2509                         entity->enum_value.value = value;
2510
2511                         /* TODO semantic */
2512                 }
2513
2514                 record_entity(entity, false);
2515         } while (next_if(',') && token.type != '}');
2516         rem_anchor_token('}');
2517
2518         expect('}', end_error);
2519
2520 end_error:
2521         ;
2522 }
2523
2524 static type_t *parse_enum_specifier(void)
2525 {
2526         source_position_t const pos = *HERE;
2527         entity_t               *entity;
2528         symbol_t               *symbol;
2529
2530         eat(T_enum);
2531         switch (token.type) {
2532                 case T_IDENTIFIER:
2533                         symbol = token.symbol;
2534                         entity = get_tag(symbol, ENTITY_ENUM);
2535                         next_token();
2536
2537                         if (entity != NULL) {
2538                                 if (entity->base.parent_scope != current_scope &&
2539                                                 (token.type == '{' || token.type == ';')) {
2540                                         /* we're in an inner scope and have a definition. Shadow
2541                                          * existing definition in outer scope */
2542                                         entity = NULL;
2543                                 } else if (entity->enume.complete && token.type == '{') {
2544                                         errorf(&pos, "multiple definitions of 'enum %Y' (previous definition %P)",
2545                                                         symbol, &entity->base.source_position);
2546                                 }
2547                         }
2548                         break;
2549
2550                 case '{':
2551                         entity = NULL;
2552                         symbol = NULL;
2553                         break;
2554
2555                 default:
2556                         parse_error_expected("while parsing enum type specifier",
2557                                         T_IDENTIFIER, '{', NULL);
2558                         return NULL;
2559         }
2560
2561         if (entity == NULL) {
2562                 entity = allocate_entity_zero(ENTITY_ENUM, NAMESPACE_TAG, symbol);
2563                 entity->base.source_position = pos;
2564                 entity->base.parent_scope    = current_scope;
2565         }
2566
2567         type_t *const type = allocate_type_zero(TYPE_ENUM);
2568         type->enumt.enume  = &entity->enume;
2569         type->enumt.akind  = ATOMIC_TYPE_INT;
2570
2571         if (token.type == '{') {
2572                 if (symbol != NULL) {
2573                         environment_push(entity);
2574                 }
2575                 append_entity(current_scope, entity);
2576                 entity->enume.complete = true;
2577
2578                 parse_enum_entries(type);
2579                 parse_attributes(NULL);
2580
2581                 /* ISO/IEC 14882:1998(E) §7.1.3:5 */
2582                 if (symbol == NULL) {
2583                         assert(anonymous_entity == NULL);
2584                         anonymous_entity = entity;
2585                 }
2586         } else if (!entity->enume.complete && !(c_mode & _GNUC)) {
2587                 errorf(HERE, "'%T' used before definition (incomplete enums are a GNU extension)", type);
2588         }
2589
2590         return type;
2591 }
2592
2593 /**
2594  * if a symbol is a typedef to another type, return true
2595  */
2596 static bool is_typedef_symbol(symbol_t *symbol)
2597 {
2598         const entity_t *const entity = get_entity(symbol, NAMESPACE_NORMAL);
2599         return entity != NULL && entity->kind == ENTITY_TYPEDEF;
2600 }
2601
2602 static type_t *parse_typeof(void)
2603 {
2604         eat(T___typeof__);
2605
2606         type_t *type;
2607
2608         expect('(', end_error);
2609         add_anchor_token(')');
2610
2611         expression_t *expression  = NULL;
2612
2613         bool old_type_prop     = in_type_prop;
2614         bool old_gcc_extension = in_gcc_extension;
2615         in_type_prop           = true;
2616
2617         while (next_if(T___extension__)) {
2618                 /* This can be a prefix to a typename or an expression. */
2619                 in_gcc_extension = true;
2620         }
2621         switch (token.type) {
2622         case T_IDENTIFIER:
2623                 if (is_typedef_symbol(token.symbol)) {
2624         DECLARATION_START
2625                         type = parse_typename();
2626                 } else {
2627         default:
2628                         expression = parse_expression();
2629                         type       = revert_automatic_type_conversion(expression);
2630                 }
2631                 break;
2632         }
2633         in_type_prop     = old_type_prop;
2634         in_gcc_extension = old_gcc_extension;
2635
2636         rem_anchor_token(')');
2637         expect(')', end_error);
2638
2639         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF);
2640         typeof_type->typeoft.expression  = expression;
2641         typeof_type->typeoft.typeof_type = type;
2642
2643         return typeof_type;
2644 end_error:
2645         return NULL;
2646 }
2647
2648 typedef enum specifiers_t {
2649         SPECIFIER_SIGNED    = 1 << 0,
2650         SPECIFIER_UNSIGNED  = 1 << 1,
2651         SPECIFIER_LONG      = 1 << 2,
2652         SPECIFIER_INT       = 1 << 3,
2653         SPECIFIER_DOUBLE    = 1 << 4,
2654         SPECIFIER_CHAR      = 1 << 5,
2655         SPECIFIER_WCHAR_T   = 1 << 6,
2656         SPECIFIER_SHORT     = 1 << 7,
2657         SPECIFIER_LONG_LONG = 1 << 8,
2658         SPECIFIER_FLOAT     = 1 << 9,
2659         SPECIFIER_BOOL      = 1 << 10,
2660         SPECIFIER_VOID      = 1 << 11,
2661         SPECIFIER_INT8      = 1 << 12,
2662         SPECIFIER_INT16     = 1 << 13,
2663         SPECIFIER_INT32     = 1 << 14,
2664         SPECIFIER_INT64     = 1 << 15,
2665         SPECIFIER_INT128    = 1 << 16,
2666         SPECIFIER_COMPLEX   = 1 << 17,
2667         SPECIFIER_IMAGINARY = 1 << 18,
2668 } specifiers_t;
2669
2670 static type_t *get_typedef_type(symbol_t *symbol)
2671 {
2672         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
2673         if (entity == NULL || entity->kind != ENTITY_TYPEDEF)
2674                 return NULL;
2675
2676         type_t *type            = allocate_type_zero(TYPE_TYPEDEF);
2677         type->typedeft.typedefe = &entity->typedefe;
2678
2679         return type;
2680 }
2681
2682 static attribute_t *parse_attribute_ms_property(attribute_t *attribute)
2683 {
2684         expect('(', end_error);
2685
2686         attribute_property_argument_t *property
2687                 = allocate_ast_zero(sizeof(*property));
2688
2689         do {
2690                 if (token.type != T_IDENTIFIER) {
2691                         parse_error_expected("while parsing property declspec",
2692                                              T_IDENTIFIER, NULL);
2693                         goto end_error;
2694                 }
2695
2696                 symbol_t **prop;
2697                 symbol_t  *symbol = token.symbol;
2698                 if (strcmp(symbol->string, "put") == 0) {
2699                         prop = &property->put_symbol;
2700                 } else if (strcmp(symbol->string, "get") == 0) {
2701                         prop = &property->get_symbol;
2702                 } else {
2703                         errorf(HERE, "expected put or get in property declspec");
2704                         prop = NULL;
2705                 }
2706                 eat(T_IDENTIFIER);
2707                 expect('=', end_error);
2708                 if (token.type != T_IDENTIFIER) {
2709                         parse_error_expected("while parsing property declspec",
2710                                              T_IDENTIFIER, NULL);
2711                         goto end_error;
2712                 }
2713                 if (prop != NULL)
2714                         *prop = token.symbol;
2715                 next_token();
2716         } while (next_if(','));
2717
2718         attribute->a.property = property;
2719
2720         expect(')', end_error);
2721
2722 end_error:
2723         return attribute;
2724 }
2725
2726 static attribute_t *parse_microsoft_extended_decl_modifier_single(void)
2727 {
2728         attribute_kind_t kind = ATTRIBUTE_UNKNOWN;
2729         if (next_if(T_restrict)) {
2730                 kind = ATTRIBUTE_MS_RESTRICT;
2731         } else if (token.type == T_IDENTIFIER) {
2732                 const char *name = token.symbol->string;
2733                 for (attribute_kind_t k = ATTRIBUTE_MS_FIRST; k <= ATTRIBUTE_MS_LAST;
2734                      ++k) {
2735                         const char *attribute_name = get_attribute_name(k);
2736                         if (attribute_name != NULL && strcmp(attribute_name, name) == 0) {
2737                                 kind = k;
2738                                 break;
2739                         }
2740                 }
2741
2742                 if (kind == ATTRIBUTE_UNKNOWN && warning.attribute) {
2743                         warningf(HERE, "unknown __declspec '%s' ignored", name);
2744                 }
2745                 eat(T_IDENTIFIER);
2746         } else {
2747                 parse_error_expected("while parsing __declspec", T_IDENTIFIER, NULL);
2748                 return NULL;
2749         }
2750
2751         attribute_t *attribute = allocate_attribute_zero(kind);
2752
2753         if (kind == ATTRIBUTE_MS_PROPERTY) {
2754                 return parse_attribute_ms_property(attribute);
2755         }
2756
2757         /* parse arguments */
2758         if (next_if('('))
2759                 attribute->a.arguments = parse_attribute_arguments();
2760
2761         return attribute;
2762 }
2763
2764 static attribute_t *parse_microsoft_extended_decl_modifier(attribute_t *first)
2765 {
2766         eat(T__declspec);
2767
2768         expect('(', end_error);
2769
2770         if (next_if(')'))
2771                 return NULL;
2772
2773         add_anchor_token(')');
2774
2775         attribute_t **anchor = &first;
2776         do {
2777                 while (*anchor != NULL)
2778                         anchor = &(*anchor)->next;
2779
2780                 attribute_t *attribute
2781                         = parse_microsoft_extended_decl_modifier_single();
2782                 if (attribute == NULL)
2783                         goto end_error;
2784
2785                 *anchor = attribute;
2786                 anchor  = &attribute->next;
2787         } while (next_if(','));
2788
2789         rem_anchor_token(')');
2790         expect(')', end_error);
2791         return first;
2792
2793 end_error:
2794         rem_anchor_token(')');
2795         return first;
2796 }
2797
2798 static entity_t *create_error_entity(symbol_t *symbol, entity_kind_tag_t kind)
2799 {
2800         entity_t *const entity = allocate_entity_zero(kind, NAMESPACE_NORMAL, symbol);
2801         entity->base.source_position = *HERE;
2802         if (is_declaration(entity)) {
2803                 entity->declaration.type     = type_error_type;
2804                 entity->declaration.implicit = true;
2805         } else if (kind == ENTITY_TYPEDEF) {
2806                 entity->typedefe.type    = type_error_type;
2807                 entity->typedefe.builtin = true;
2808         }
2809         if (kind != ENTITY_COMPOUND_MEMBER)
2810                 record_entity(entity, false);
2811         return entity;
2812 }
2813
2814 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
2815 {
2816         type_t            *type              = NULL;
2817         type_qualifiers_t  qualifiers        = TYPE_QUALIFIER_NONE;
2818         unsigned           type_specifiers   = 0;
2819         bool               newtype           = false;
2820         bool               saw_error         = false;
2821         bool               old_gcc_extension = in_gcc_extension;
2822
2823         memset(specifiers, 0, sizeof(*specifiers));
2824         specifiers->source_position = token.source_position;
2825
2826         while (true) {
2827                 specifiers->attributes = parse_attributes(specifiers->attributes);
2828
2829                 switch (token.type) {
2830                 /* storage class */
2831 #define MATCH_STORAGE_CLASS(token, class)                                  \
2832                 case token:                                                        \
2833                         if (specifiers->storage_class != STORAGE_CLASS_NONE) {         \
2834                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
2835                         }                                                              \
2836                         specifiers->storage_class = class;                             \
2837                         if (specifiers->thread_local)                                  \
2838                                 goto check_thread_storage_class;                           \
2839                         next_token();                                                  \
2840                         break;
2841
2842                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
2843                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
2844                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
2845                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
2846                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
2847
2848                 case T__declspec:
2849                         specifiers->attributes
2850                                 = parse_microsoft_extended_decl_modifier(specifiers->attributes);
2851                         break;
2852
2853                 case T___thread:
2854                         if (specifiers->thread_local) {
2855                                 errorf(HERE, "duplicate '__thread'");
2856                         } else {
2857                                 specifiers->thread_local = true;
2858 check_thread_storage_class:
2859                                 switch (specifiers->storage_class) {
2860                                         case STORAGE_CLASS_EXTERN:
2861                                         case STORAGE_CLASS_NONE:
2862                                         case STORAGE_CLASS_STATIC:
2863                                                 break;
2864
2865                                                 char const* wrong;
2866                                         case STORAGE_CLASS_AUTO:     wrong = "auto";     goto wrong_thread_storage_class;
2867                                         case STORAGE_CLASS_REGISTER: wrong = "register"; goto wrong_thread_storage_class;
2868                                         case STORAGE_CLASS_TYPEDEF:  wrong = "typedef";  goto wrong_thread_storage_class;
2869 wrong_thread_storage_class:
2870                                                 errorf(HERE, "'__thread' used with '%s'", wrong);
2871                                                 break;
2872                                 }
2873                         }
2874                         next_token();
2875                         break;
2876
2877                 /* type qualifiers */
2878 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
2879                 case token:                                                     \
2880                         qualifiers |= qualifier;                                    \
2881                         next_token();                                               \
2882                         break
2883
2884                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
2885                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
2886                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
2887                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
2888                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
2889                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
2890                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
2891                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
2892
2893                 case T___extension__:
2894                         next_token();
2895                         in_gcc_extension = true;
2896                         break;
2897
2898                 /* type specifiers */
2899 #define MATCH_SPECIFIER(token, specifier, name)                         \
2900                 case token:                                                     \
2901                         if (type_specifiers & specifier) {                           \
2902                                 errorf(HERE, "multiple " name " type specifiers given"); \
2903                         } else {                                                    \
2904                                 type_specifiers |= specifier;                           \
2905                         }                                                           \
2906                         next_token();                                               \
2907                         break
2908
2909                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
2910                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
2911                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
2912                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
2913                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
2914                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
2915                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
2916                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
2917                 MATCH_SPECIFIER(T_bool,       SPECIFIER_BOOL,      "bool");
2918                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
2919                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
2920                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
2921                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
2922                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
2923                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
2924                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
2925                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
2926                 MATCH_SPECIFIER(T_wchar_t,    SPECIFIER_WCHAR_T,   "wchar_t");
2927
2928                 case T_inline:
2929                         next_token();
2930                         specifiers->is_inline = true;
2931                         break;
2932
2933 #if 0
2934                 case T__forceinline:
2935                         next_token();
2936                         specifiers->modifiers |= DM_FORCEINLINE;
2937                         break;
2938 #endif
2939
2940                 case T_long:
2941                         if (type_specifiers & SPECIFIER_LONG_LONG) {
2942                                 errorf(HERE, "too many long type specifiers given");
2943                         } else if (type_specifiers & SPECIFIER_LONG) {
2944                                 type_specifiers |= SPECIFIER_LONG_LONG;
2945                         } else {
2946                                 type_specifiers |= SPECIFIER_LONG;
2947                         }
2948                         next_token();
2949                         break;
2950
2951 #define CHECK_DOUBLE_TYPE()        \
2952                         if ( type != NULL)     \
2953                                 errorf(HERE, "multiple data types in declaration specifiers");
2954
2955                 case T_struct:
2956                         CHECK_DOUBLE_TYPE();
2957                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
2958
2959                         type->compound.compound = parse_compound_type_specifier(true);
2960                         break;
2961                 case T_union:
2962                         CHECK_DOUBLE_TYPE();
2963                         type = allocate_type_zero(TYPE_COMPOUND_UNION);
2964                         type->compound.compound = parse_compound_type_specifier(false);
2965                         break;
2966                 case T_enum:
2967                         CHECK_DOUBLE_TYPE();
2968                         type = parse_enum_specifier();
2969                         break;
2970                 case T___typeof__:
2971                         CHECK_DOUBLE_TYPE();
2972                         type = parse_typeof();
2973                         break;
2974                 case T___builtin_va_list:
2975                         CHECK_DOUBLE_TYPE();
2976                         type = duplicate_type(type_valist);
2977                         next_token();
2978                         break;
2979
2980                 case T_IDENTIFIER: {
2981                         /* only parse identifier if we haven't found a type yet */
2982                         if (type != NULL || type_specifiers != 0) {
2983                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
2984                                  * declaration, so it doesn't generate errors about expecting '(' or
2985                                  * '{' later on. */
2986                                 switch (look_ahead(1)->type) {
2987                                         STORAGE_CLASSES
2988                                         TYPE_SPECIFIERS
2989                                         case T_const:
2990                                         case T_restrict:
2991                                         case T_volatile:
2992                                         case T_inline:
2993                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
2994                                         case T_IDENTIFIER:
2995                                         case '&':
2996                                         case '*':
2997                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
2998                                                 next_token();
2999                                                 continue;
3000
3001                                         default:
3002                                                 goto finish_specifiers;
3003                                 }
3004                         }
3005
3006                         type_t *const typedef_type = get_typedef_type(token.symbol);
3007                         if (typedef_type == NULL) {
3008                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3009                                  * declaration, so it doesn't generate 'implicit int' followed by more
3010                                  * errors later on. */
3011                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3012                                 switch (la1_type) {
3013                                         DECLARATION_START
3014                                         case T_IDENTIFIER:
3015                                         case '&':
3016                                         case '*': {
3017                                                 errorf(HERE, "%K does not name a type", &token);
3018
3019                                                 entity_t *entity =
3020                                                         create_error_entity(token.symbol, ENTITY_TYPEDEF);
3021
3022                                                 type = allocate_type_zero(TYPE_TYPEDEF);
3023                                                 type->typedeft.typedefe = &entity->typedefe;
3024
3025                                                 next_token();
3026                                                 saw_error = true;
3027                                                 continue;
3028                                         }
3029
3030                                         default:
3031                                                 goto finish_specifiers;
3032                                 }
3033                         }
3034
3035                         next_token();
3036                         type = typedef_type;
3037                         break;
3038                 }
3039
3040                 /* function specifier */
3041                 default:
3042                         goto finish_specifiers;
3043                 }
3044         }
3045
3046 finish_specifiers:
3047         specifiers->attributes = parse_attributes(specifiers->attributes);
3048
3049         in_gcc_extension = old_gcc_extension;
3050
3051         if (type == NULL || (saw_error && type_specifiers != 0)) {
3052                 atomic_type_kind_t atomic_type;
3053
3054                 /* match valid basic types */
3055                 switch (type_specifiers) {
3056                 case SPECIFIER_VOID:
3057                         atomic_type = ATOMIC_TYPE_VOID;
3058                         break;
3059                 case SPECIFIER_WCHAR_T:
3060                         atomic_type = ATOMIC_TYPE_WCHAR_T;
3061                         break;
3062                 case SPECIFIER_CHAR:
3063                         atomic_type = ATOMIC_TYPE_CHAR;
3064                         break;
3065                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3066                         atomic_type = ATOMIC_TYPE_SCHAR;
3067                         break;
3068                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3069                         atomic_type = ATOMIC_TYPE_UCHAR;
3070                         break;
3071                 case SPECIFIER_SHORT:
3072                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3073                 case SPECIFIER_SHORT | SPECIFIER_INT:
3074                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3075                         atomic_type = ATOMIC_TYPE_SHORT;
3076                         break;
3077                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3078                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3079                         atomic_type = ATOMIC_TYPE_USHORT;
3080                         break;
3081                 case SPECIFIER_INT:
3082                 case SPECIFIER_SIGNED:
3083                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3084                         atomic_type = ATOMIC_TYPE_INT;
3085                         break;
3086                 case SPECIFIER_UNSIGNED:
3087                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3088                         atomic_type = ATOMIC_TYPE_UINT;
3089                         break;
3090                 case SPECIFIER_LONG:
3091                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3092                 case SPECIFIER_LONG | SPECIFIER_INT:
3093                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3094                         atomic_type = ATOMIC_TYPE_LONG;
3095                         break;
3096                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3097                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3098                         atomic_type = ATOMIC_TYPE_ULONG;
3099                         break;
3100
3101                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3102                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3103                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3104                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3105                         | SPECIFIER_INT:
3106                         atomic_type = ATOMIC_TYPE_LONGLONG;
3107                         goto warn_about_long_long;
3108
3109                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3110                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3111                         | SPECIFIER_INT:
3112                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3113 warn_about_long_long:
3114                         if (warning.long_long) {
3115                                 warningf(&specifiers->source_position,
3116                                          "ISO C90 does not support 'long long'");
3117                         }
3118                         break;
3119
3120                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3121                         atomic_type = unsigned_int8_type_kind;
3122                         break;
3123
3124                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3125                         atomic_type = unsigned_int16_type_kind;
3126                         break;
3127
3128                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3129                         atomic_type = unsigned_int32_type_kind;
3130                         break;
3131
3132                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3133                         atomic_type = unsigned_int64_type_kind;
3134                         break;
3135
3136                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3137                         atomic_type = unsigned_int128_type_kind;
3138                         break;
3139
3140                 case SPECIFIER_INT8:
3141                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3142                         atomic_type = int8_type_kind;
3143                         break;
3144
3145                 case SPECIFIER_INT16:
3146                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3147                         atomic_type = int16_type_kind;
3148                         break;
3149
3150                 case SPECIFIER_INT32:
3151                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3152                         atomic_type = int32_type_kind;
3153                         break;
3154
3155                 case SPECIFIER_INT64:
3156                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3157                         atomic_type = int64_type_kind;
3158                         break;
3159
3160                 case SPECIFIER_INT128:
3161                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3162                         atomic_type = int128_type_kind;
3163                         break;
3164
3165                 case SPECIFIER_FLOAT:
3166                         atomic_type = ATOMIC_TYPE_FLOAT;
3167                         break;
3168                 case SPECIFIER_DOUBLE:
3169                         atomic_type = ATOMIC_TYPE_DOUBLE;
3170                         break;
3171                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3172                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3173                         break;
3174                 case SPECIFIER_BOOL:
3175                         atomic_type = ATOMIC_TYPE_BOOL;
3176                         break;
3177                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3178                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3179                         atomic_type = ATOMIC_TYPE_FLOAT;
3180                         break;
3181                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3182                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3183                         atomic_type = ATOMIC_TYPE_DOUBLE;
3184                         break;
3185                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3186                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3187                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3188                         break;
3189                 default: {
3190                         /* invalid specifier combination, give an error message */
3191                         source_position_t const* const pos = &specifiers->source_position;
3192                         if (type_specifiers == 0) {
3193                                 if (!saw_error) {
3194                                         /* ISO/IEC 14882:1998(E) §C.1.5:4 */
3195                                         if (!(c_mode & _CXX) && !strict_mode) {
3196                                                 if (warning.implicit_int) {
3197                                                         warningf(pos, "no type specifiers in declaration, using 'int'");
3198                                                 }
3199                                                 atomic_type = ATOMIC_TYPE_INT;
3200                                                 break;
3201                                         } else {
3202                                                 errorf(pos, "no type specifiers given in declaration");
3203                                         }
3204                                 }
3205                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3206                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3207                                 errorf(pos, "signed and unsigned specifiers given");
3208                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3209                                 errorf(pos, "only integer types can be signed or unsigned");
3210                         } else {
3211                                 errorf(pos, "multiple datatypes in declaration");
3212                         }
3213                         goto end_error;
3214                 }
3215                 }
3216
3217                 if (type_specifiers & SPECIFIER_COMPLEX) {
3218                         type                = allocate_type_zero(TYPE_COMPLEX);
3219                         type->complex.akind = atomic_type;
3220                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
3221                         type                  = allocate_type_zero(TYPE_IMAGINARY);
3222                         type->imaginary.akind = atomic_type;
3223                 } else {
3224                         type                 = allocate_type_zero(TYPE_ATOMIC);
3225                         type->atomic.akind   = atomic_type;
3226                 }
3227                 newtype = true;
3228         } else if (type_specifiers != 0) {
3229                 errorf(&specifiers->source_position, "multiple datatypes in declaration");
3230         }
3231
3232         /* FIXME: check type qualifiers here */
3233         type->base.qualifiers = qualifiers;
3234
3235         if (newtype) {
3236                 type = identify_new_type(type);
3237         } else {
3238                 type = typehash_insert(type);
3239         }
3240
3241         if (specifiers->attributes != NULL)
3242                 type = handle_type_attributes(specifiers->attributes, type);
3243         specifiers->type = type;
3244         return;
3245
3246 end_error:
3247         specifiers->type = type_error_type;
3248 }
3249
3250 static type_qualifiers_t parse_type_qualifiers(void)
3251 {
3252         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3253
3254         while (true) {
3255                 switch (token.type) {
3256                 /* type qualifiers */
3257                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3258                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3259                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3260                 /* microsoft extended type modifiers */
3261                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3262                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3263                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3264                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3265                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3266
3267                 default:
3268                         return qualifiers;
3269                 }
3270         }
3271 }
3272
3273 /**
3274  * Parses an K&R identifier list
3275  */
3276 static void parse_identifier_list(scope_t *scope)
3277 {
3278         do {
3279                 entity_t *const entity = allocate_entity_zero(ENTITY_PARAMETER, NAMESPACE_NORMAL, token.symbol);
3280                 entity->base.source_position = token.source_position;
3281                 /* a K&R parameter has no type, yet */
3282                 next_token();
3283
3284                 if (scope != NULL)
3285                         append_entity(scope, entity);
3286         } while (next_if(',') && token.type == T_IDENTIFIER);
3287 }
3288
3289 static entity_t *parse_parameter(void)
3290 {
3291         declaration_specifiers_t specifiers;
3292         parse_declaration_specifiers(&specifiers);
3293
3294         entity_t *entity = parse_declarator(&specifiers,
3295                         DECL_MAY_BE_ABSTRACT | DECL_IS_PARAMETER);
3296         anonymous_entity = NULL;
3297         return entity;
3298 }
3299
3300 static void semantic_parameter_incomplete(const entity_t *entity)
3301 {
3302         assert(entity->kind == ENTITY_PARAMETER);
3303
3304         /* §6.7.5.3:4  After adjustment, the parameters in a parameter type
3305          *             list in a function declarator that is part of a
3306          *             definition of that function shall not have
3307          *             incomplete type. */
3308         type_t *type = skip_typeref(entity->declaration.type);
3309         if (is_type_incomplete(type)) {
3310                 errorf(&entity->base.source_position,
3311                                 "parameter '%#T' has incomplete type",
3312                                 entity->declaration.type, entity->base.symbol);
3313         }
3314 }
3315
3316 static bool has_parameters(void)
3317 {
3318         /* func(void) is not a parameter */
3319         if (token.type == T_IDENTIFIER) {
3320                 entity_t const *const entity = get_entity(token.symbol, NAMESPACE_NORMAL);
3321                 if (entity == NULL)
3322                         return true;
3323                 if (entity->kind != ENTITY_TYPEDEF)
3324                         return true;
3325                 if (skip_typeref(entity->typedefe.type) != type_void)
3326                         return true;
3327         } else if (token.type != T_void) {
3328                 return true;
3329         }
3330         if (look_ahead(1)->type != ')')
3331                 return true;
3332         next_token();
3333         return false;
3334 }
3335
3336 /**
3337  * Parses function type parameters (and optionally creates variable_t entities
3338  * for them in a scope)
3339  */
3340 static void parse_parameters(function_type_t *type, scope_t *scope)
3341 {
3342         eat('(');
3343         add_anchor_token(')');
3344         int saved_comma_state = save_and_reset_anchor_state(',');
3345
3346         if (token.type == T_IDENTIFIER &&
3347             !is_typedef_symbol(token.symbol)) {
3348                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
3349                 if (la1_type == ',' || la1_type == ')') {
3350                         type->kr_style_parameters = true;
3351                         parse_identifier_list(scope);
3352                         goto parameters_finished;
3353                 }
3354         }
3355
3356         if (token.type == ')') {
3357                 /* ISO/IEC 14882:1998(E) §C.1.6:1 */
3358                 if (!(c_mode & _CXX))
3359                         type->unspecified_parameters = true;
3360         } else if (has_parameters()) {
3361                 function_parameter_t **anchor = &type->parameters;
3362                 do {
3363                         switch (token.type) {
3364                         case T_DOTDOTDOT:
3365                                 next_token();
3366                                 type->variadic = true;
3367                                 goto parameters_finished;
3368
3369                         case T_IDENTIFIER:
3370                         case T___extension__:
3371                         DECLARATION_START
3372                         {
3373                                 entity_t *entity = parse_parameter();
3374                                 if (entity->kind == ENTITY_TYPEDEF) {
3375                                         errorf(&entity->base.source_position,
3376                                                         "typedef not allowed as function parameter");
3377                                         break;
3378                                 }
3379                                 assert(is_declaration(entity));
3380
3381                                 semantic_parameter_incomplete(entity);
3382
3383                                 function_parameter_t *const parameter =
3384                                         allocate_parameter(entity->declaration.type);
3385
3386                                 if (scope != NULL) {
3387                                         append_entity(scope, entity);
3388                                 }
3389
3390                                 *anchor = parameter;
3391                                 anchor  = &parameter->next;
3392                                 break;
3393                         }
3394
3395                         default:
3396                                 goto parameters_finished;
3397                         }
3398                 } while (next_if(','));
3399         }
3400
3401 parameters_finished:
3402         rem_anchor_token(')');
3403         expect(')', end_error);
3404
3405 end_error:
3406         restore_anchor_state(',', saved_comma_state);
3407 }
3408
3409 typedef enum construct_type_kind_t {
3410         CONSTRUCT_INVALID,
3411         CONSTRUCT_POINTER,
3412         CONSTRUCT_REFERENCE,
3413         CONSTRUCT_FUNCTION,
3414         CONSTRUCT_ARRAY
3415 } construct_type_kind_t;
3416
3417 typedef union construct_type_t construct_type_t;
3418
3419 typedef struct construct_type_base_t {
3420         construct_type_kind_t  kind;
3421         source_position_t      pos;
3422         construct_type_t      *next;
3423 } construct_type_base_t;
3424
3425 typedef struct parsed_pointer_t {
3426         construct_type_base_t  base;
3427         type_qualifiers_t      type_qualifiers;
3428         variable_t            *base_variable;  /**< MS __based extension. */
3429 } parsed_pointer_t;
3430
3431 typedef struct parsed_reference_t {
3432         construct_type_base_t base;
3433 } parsed_reference_t;
3434
3435 typedef struct construct_function_type_t {
3436         construct_type_base_t  base;
3437         type_t                *function_type;
3438 } construct_function_type_t;
3439
3440 typedef struct parsed_array_t {
3441         construct_type_base_t  base;
3442         type_qualifiers_t      type_qualifiers;
3443         bool                   is_static;
3444         bool                   is_variable;
3445         expression_t          *size;
3446 } parsed_array_t;
3447
3448 union construct_type_t {
3449         construct_type_kind_t     kind;
3450         construct_type_base_t     base;
3451         parsed_pointer_t          pointer;
3452         parsed_reference_t        reference;
3453         construct_function_type_t function;
3454         parsed_array_t            array;
3455 };
3456
3457 static construct_type_t *allocate_declarator_zero(construct_type_kind_t const kind, size_t const size)
3458 {
3459         construct_type_t *const cons = obstack_alloc(&temp_obst, size);
3460         memset(cons, 0, size);
3461         cons->kind     = kind;
3462         cons->base.pos = *HERE;
3463         return cons;
3464 }
3465
3466 /* §6.7.5.1 */
3467 static construct_type_t *parse_pointer_declarator(void)
3468 {
3469         construct_type_t *const cons = allocate_declarator_zero(CONSTRUCT_POINTER, sizeof(parsed_pointer_t));
3470         eat('*');
3471         cons->pointer.type_qualifiers = parse_type_qualifiers();
3472         //cons->pointer.base_variable   = base_variable;
3473
3474         return cons;
3475 }
3476
3477 /* ISO/IEC 14882:1998(E) §8.3.2 */
3478 static construct_type_t *parse_reference_declarator(void)
3479 {
3480         if (!(c_mode & _CXX))
3481                 errorf(HERE, "references are only available for C++");
3482
3483         construct_type_t *const cons = allocate_declarator_zero(CONSTRUCT_REFERENCE, sizeof(parsed_reference_t));
3484         eat('&');
3485
3486         return cons;
3487 }
3488
3489 /* §6.7.5.2 */
3490 static construct_type_t *parse_array_declarator(void)
3491 {
3492         construct_type_t *const cons  = allocate_declarator_zero(CONSTRUCT_ARRAY, sizeof(parsed_array_t));
3493         parsed_array_t   *const array = &cons->array;
3494
3495         eat('[');
3496         add_anchor_token(']');
3497
3498         bool is_static = next_if(T_static);
3499
3500         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
3501
3502         if (!is_static)
3503                 is_static = next_if(T_static);
3504
3505         array->type_qualifiers = type_qualifiers;
3506         array->is_static       = is_static;
3507
3508         expression_t *size = NULL;
3509         if (token.type == '*' && look_ahead(1)->type == ']') {
3510                 array->is_variable = true;
3511                 next_token();
3512         } else if (token.type != ']') {
3513                 size = parse_assignment_expression();
3514
3515                 /* §6.7.5.2:1  Array size must have integer type */
3516                 type_t *const orig_type = size->base.type;
3517                 type_t *const type      = skip_typeref(orig_type);
3518                 if (!is_type_integer(type) && is_type_valid(type)) {
3519                         errorf(&size->base.source_position,
3520                                "array size '%E' must have integer type but has type '%T'",
3521                                size, orig_type);
3522                 }
3523
3524                 array->size = size;
3525                 mark_vars_read(size, NULL);
3526         }
3527
3528         if (is_static && size == NULL)
3529                 errorf(&array->base.pos, "static array parameters require a size");
3530
3531         rem_anchor_token(']');
3532         expect(']', end_error);
3533
3534 end_error:
3535         return cons;
3536 }
3537
3538 /* §6.7.5.3 */
3539 static construct_type_t *parse_function_declarator(scope_t *scope)
3540 {
3541         construct_type_t *const cons = allocate_declarator_zero(CONSTRUCT_FUNCTION, sizeof(construct_function_type_t));
3542
3543         type_t          *type  = allocate_type_zero(TYPE_FUNCTION);
3544         function_type_t *ftype = &type->function;
3545
3546         ftype->linkage            = current_linkage;
3547         ftype->calling_convention = CC_DEFAULT;
3548
3549         parse_parameters(ftype, scope);
3550
3551         cons->function.function_type = type;
3552
3553         return cons;
3554 }
3555
3556 typedef struct parse_declarator_env_t {
3557         bool               may_be_abstract : 1;
3558         bool               must_be_abstract : 1;
3559         decl_modifiers_t   modifiers;
3560         symbol_t          *symbol;
3561         source_position_t  source_position;
3562         scope_t            parameters;
3563         attribute_t       *attributes;
3564 } parse_declarator_env_t;
3565
3566 /* §6.7.5 */
3567 static construct_type_t *parse_inner_declarator(parse_declarator_env_t *env)
3568 {
3569         /* construct a single linked list of construct_type_t's which describe
3570          * how to construct the final declarator type */
3571         construct_type_t  *first      = NULL;
3572         construct_type_t **anchor     = &first;
3573
3574         env->attributes = parse_attributes(env->attributes);
3575
3576         for (;;) {
3577                 construct_type_t *type;
3578                 //variable_t       *based = NULL; /* MS __based extension */
3579                 switch (token.type) {
3580                         case '&':
3581                                 type = parse_reference_declarator();
3582                                 break;
3583
3584                         case T__based: {
3585                                 panic("based not supported anymore");
3586                                 /* FALLTHROUGH */
3587                         }
3588
3589                         case '*':
3590                                 type = parse_pointer_declarator();
3591                                 break;
3592
3593                         default:
3594                                 goto ptr_operator_end;
3595                 }
3596
3597                 *anchor = type;
3598                 anchor  = &type->base.next;
3599
3600                 /* TODO: find out if this is correct */
3601                 env->attributes = parse_attributes(env->attributes);
3602         }
3603
3604 ptr_operator_end: ;
3605         construct_type_t *inner_types = NULL;
3606
3607         switch (token.type) {
3608         case T_IDENTIFIER:
3609                 if (env->must_be_abstract) {
3610                         errorf(HERE, "no identifier expected in typename");
3611                 } else {
3612                         env->symbol          = token.symbol;
3613                         env->source_position = token.source_position;
3614                 }
3615                 next_token();
3616                 break;
3617
3618         case '(': {
3619                 /* Parenthesized declarator or function declarator? */
3620                 token_t const *const la1 = look_ahead(1);
3621                 switch (la1->type) {
3622                         case T_IDENTIFIER:
3623                                 if (is_typedef_symbol(la1->symbol)) {
3624                         case ')':
3625                                         /* §6.7.6:2 footnote 126:  Empty parentheses in a type name are
3626                                          * interpreted as ``function with no parameter specification'', rather
3627                                          * than redundant parentheses around the omitted identifier. */
3628                         default:
3629                                         /* Function declarator. */
3630                                         if (!env->may_be_abstract) {
3631                                                 errorf(HERE, "function declarator must have a name");
3632                                         }
3633                                 } else {
3634                         case '&':
3635                         case '(':
3636                         case '*':
3637                         case '[':
3638                         case T___attribute__: /* FIXME __attribute__ might also introduce a parameter of a function declarator. */
3639                                         /* Paranthesized declarator. */
3640                                         next_token();
3641                                         add_anchor_token(')');
3642                                         inner_types = parse_inner_declarator(env);
3643                                         if (inner_types != NULL) {
3644                                                 /* All later declarators only modify the return type */
3645                                                 env->must_be_abstract = true;
3646                                         }
3647                                         rem_anchor_token(')');
3648                                         expect(')', end_error);
3649                                 }
3650                                 break;
3651                 }
3652                 break;
3653         }
3654
3655         default:
3656                 if (env->may_be_abstract)
3657                         break;
3658                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
3659                 eat_until_anchor();
3660                 return NULL;
3661         }
3662
3663         construct_type_t **const p = anchor;
3664
3665         for (;;) {
3666                 construct_type_t *type;
3667                 switch (token.type) {
3668                 case '(': {
3669                         scope_t *scope = NULL;
3670                         if (!env->must_be_abstract) {
3671                                 scope = &env->parameters;
3672                         }
3673
3674                         type = parse_function_declarator(scope);
3675                         break;
3676                 }
3677                 case '[':
3678                         type = parse_array_declarator();
3679                         break;
3680                 default:
3681                         goto declarator_finished;
3682                 }
3683
3684                 /* insert in the middle of the list (at p) */
3685                 type->base.next = *p;
3686                 *p              = type;
3687                 if (anchor == p)
3688                         anchor = &type->base.next;
3689         }
3690
3691 declarator_finished:
3692         /* append inner_types at the end of the list, we don't to set anchor anymore
3693          * as it's not needed anymore */
3694         *anchor = inner_types;
3695
3696         return first;
3697 end_error:
3698         return NULL;
3699 }
3700
3701 static type_t *construct_declarator_type(construct_type_t *construct_list,
3702                                          type_t *type)
3703 {
3704         construct_type_t *iter = construct_list;
3705         for (; iter != NULL; iter = iter->base.next) {
3706                 source_position_t const* const pos = &iter->base.pos;
3707                 switch (iter->kind) {
3708                 case CONSTRUCT_INVALID:
3709                         break;
3710                 case CONSTRUCT_FUNCTION: {
3711                         construct_function_type_t *function      = &iter->function;
3712                         type_t                    *function_type = function->function_type;
3713
3714                         function_type->function.return_type = type;
3715
3716                         type_t *skipped_return_type = skip_typeref(type);
3717                         /* §6.7.5.3:1 */
3718                         if (is_type_function(skipped_return_type)) {
3719                                 errorf(pos, "function returning function is not allowed");
3720                         } else if (is_type_array(skipped_return_type)) {
3721                                 errorf(pos, "function returning array is not allowed");
3722                         } else {
3723                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
3724                                         warningf(pos, "type qualifiers in return type of function type are meaningless");
3725                                 }
3726                         }
3727
3728                         /* The function type was constructed earlier.  Freeing it here will
3729                          * destroy other types. */
3730                         type = typehash_insert(function_type);
3731                         continue;
3732                 }
3733
3734                 case CONSTRUCT_POINTER: {
3735                         if (is_type_reference(skip_typeref(type)))
3736                                 errorf(pos, "cannot declare a pointer to reference");
3737
3738                         parsed_pointer_t *pointer = &iter->pointer;
3739                         type = make_based_pointer_type(type, pointer->type_qualifiers, pointer->base_variable);
3740                         continue;
3741                 }
3742
3743                 case CONSTRUCT_REFERENCE:
3744                         if (is_type_reference(skip_typeref(type)))
3745                                 errorf(pos, "cannot declare a reference to reference");
3746
3747                         type = make_reference_type(type);
3748                         continue;
3749
3750                 case CONSTRUCT_ARRAY: {
3751                         if (is_type_reference(skip_typeref(type)))
3752                                 errorf(pos, "cannot declare an array of references");
3753
3754                         parsed_array_t *array      = &iter->array;
3755                         type_t         *array_type = allocate_type_zero(TYPE_ARRAY);
3756
3757                         expression_t *size_expression = array->size;
3758                         if (size_expression != NULL) {
3759                                 size_expression
3760                                         = create_implicit_cast(size_expression, type_size_t);
3761                         }
3762
3763                         array_type->base.qualifiers       = array->type_qualifiers;
3764                         array_type->array.element_type    = type;
3765                         array_type->array.is_static       = array->is_static;
3766                         array_type->array.is_variable     = array->is_variable;
3767                         array_type->array.size_expression = size_expression;
3768
3769                         if (size_expression != NULL) {
3770                                 switch (is_constant_expression(size_expression)) {
3771                                         case EXPR_CLASS_CONSTANT: {
3772                                                 long const size = fold_constant_to_int(size_expression);
3773                                                 array_type->array.size          = size;
3774                                                 array_type->array.size_constant = true;
3775                                                 /* §6.7.5.2:1  If the expression is a constant expression, it shall
3776                                                  * have a value greater than zero. */
3777                                                 if (size <= 0) {
3778                                                         if (size < 0 || !GNU_MODE) {
3779                                                                 errorf(&size_expression->base.source_position,
3780                                                                                 "size of array must be greater than zero");
3781                                                         } else if (warning.other) {
3782                                                                 warningf(&size_expression->base.source_position,
3783                                                                                 "zero length arrays are a GCC extension");
3784                                                         }
3785                                                 }
3786                                                 break;
3787                                         }
3788
3789                                         case EXPR_CLASS_VARIABLE:
3790                                                 array_type->array.is_vla = true;
3791                                                 break;
3792
3793                                         case EXPR_CLASS_ERROR:
3794                                                 break;
3795                                 }
3796                         }
3797
3798                         type_t *skipped_type = skip_typeref(type);
3799                         /* §6.7.5.2:1 */
3800                         if (is_type_incomplete(skipped_type)) {
3801                                 errorf(pos, "array of incomplete type '%T' is not allowed", type);
3802                         } else if (is_type_function(skipped_type)) {
3803                                 errorf(pos, "array of functions is not allowed");
3804                         }
3805                         type = identify_new_type(array_type);
3806                         continue;
3807                 }
3808                 }
3809                 internal_errorf(pos, "invalid type construction found");
3810         }
3811
3812         return type;
3813 }
3814
3815 static type_t *automatic_type_conversion(type_t *orig_type);
3816
3817 static type_t *semantic_parameter(const source_position_t *pos,
3818                                   type_t *type,
3819                                   const declaration_specifiers_t *specifiers,
3820                                   symbol_t *symbol)
3821 {
3822         /* §6.7.5.3:7  A declaration of a parameter as ``array of type''
3823          *             shall be adjusted to ``qualified pointer to type'',
3824          *             [...]
3825          * §6.7.5.3:8  A declaration of a parameter as ``function returning
3826          *             type'' shall be adjusted to ``pointer to function
3827          *             returning type'', as in 6.3.2.1. */
3828         type = automatic_type_conversion(type);
3829
3830         if (specifiers->is_inline && is_type_valid(type)) {
3831                 errorf(pos, "parameter '%#T' declared 'inline'", type, symbol);
3832         }
3833
3834         /* §6.9.1:6  The declarations in the declaration list shall contain
3835          *           no storage-class specifier other than register and no
3836          *           initializations. */
3837         if (specifiers->thread_local || (
3838                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
3839                         specifiers->storage_class != STORAGE_CLASS_REGISTER)
3840            ) {
3841                 errorf(pos, "invalid storage class for parameter '%#T'", type, symbol);
3842         }
3843
3844         /* delay test for incomplete type, because we might have (void)
3845          * which is legal but incomplete... */
3846
3847         return type;
3848 }
3849
3850 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
3851                                   declarator_flags_t flags)
3852 {
3853         parse_declarator_env_t env;
3854         memset(&env, 0, sizeof(env));
3855         env.may_be_abstract = (flags & DECL_MAY_BE_ABSTRACT) != 0;
3856
3857         construct_type_t *construct_type = parse_inner_declarator(&env);
3858         type_t           *orig_type      =
3859                 construct_declarator_type(construct_type, specifiers->type);
3860         type_t           *type           = skip_typeref(orig_type);
3861
3862         if (construct_type != NULL) {
3863                 obstack_free(&temp_obst, construct_type);
3864         }
3865
3866         attribute_t *attributes = parse_attributes(env.attributes);
3867         /* append (shared) specifier attribute behind attributes of this
3868          * declarator */
3869         attribute_t **anchor = &attributes;
3870         while (*anchor != NULL)
3871                 anchor = &(*anchor)->next;
3872         *anchor = specifiers->attributes;
3873
3874         entity_t *entity;
3875         if (specifiers->storage_class == STORAGE_CLASS_TYPEDEF) {
3876                 entity = allocate_entity_zero(ENTITY_TYPEDEF, NAMESPACE_NORMAL, env.symbol);
3877                 entity->base.source_position = env.source_position;
3878                 entity->typedefe.type        = orig_type;
3879
3880                 if (anonymous_entity != NULL) {
3881                         if (is_type_compound(type)) {
3882                                 assert(anonymous_entity->compound.alias == NULL);
3883                                 assert(anonymous_entity->kind == ENTITY_STRUCT ||
3884                                        anonymous_entity->kind == ENTITY_UNION);
3885                                 anonymous_entity->compound.alias = entity;
3886                                 anonymous_entity = NULL;
3887                         } else if (is_type_enum(type)) {
3888                                 assert(anonymous_entity->enume.alias == NULL);
3889                                 assert(anonymous_entity->kind == ENTITY_ENUM);
3890                                 anonymous_entity->enume.alias = entity;
3891                                 anonymous_entity = NULL;
3892                         }
3893                 }
3894         } else {
3895                 /* create a declaration type entity */
3896                 if (flags & DECL_CREATE_COMPOUND_MEMBER) {
3897                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER, NAMESPACE_NORMAL, env.symbol);
3898
3899                         if (env.symbol != NULL) {
3900                                 if (specifiers->is_inline && is_type_valid(type)) {
3901                                         errorf(&env.source_position,
3902                                                         "compound member '%Y' declared 'inline'", env.symbol);
3903                                 }
3904
3905                                 if (specifiers->thread_local ||
3906                                                 specifiers->storage_class != STORAGE_CLASS_NONE) {
3907                                         errorf(&env.source_position,
3908                                                         "compound member '%Y' must have no storage class",
3909                                                         env.symbol);
3910                                 }
3911                         }
3912                 } else if (flags & DECL_IS_PARAMETER) {
3913                         orig_type = semantic_parameter(&env.source_position, orig_type,
3914                                                        specifiers, env.symbol);
3915
3916                         entity = allocate_entity_zero(ENTITY_PARAMETER, NAMESPACE_NORMAL, env.symbol);
3917                 } else if (is_type_function(type)) {
3918                         entity = allocate_entity_zero(ENTITY_FUNCTION, NAMESPACE_NORMAL, env.symbol);
3919                         entity->function.is_inline      = specifiers->is_inline;
3920                         entity->function.elf_visibility = default_visibility;
3921                         entity->function.parameters     = env.parameters;
3922
3923                         if (env.symbol != NULL) {
3924                                 /* this needs fixes for C++ */
3925                                 bool in_function_scope = current_function != NULL;
3926
3927                                 if (specifiers->thread_local || (
3928                                                         specifiers->storage_class != STORAGE_CLASS_EXTERN &&
3929                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
3930                                                         (in_function_scope || specifiers->storage_class != STORAGE_CLASS_STATIC)
3931                                                 )) {
3932                                         errorf(&env.source_position,
3933                                                         "invalid storage class for function '%Y'", env.symbol);
3934                                 }
3935                         }
3936                 } else {
3937                         entity = allocate_entity_zero(ENTITY_VARIABLE, NAMESPACE_NORMAL, env.symbol);
3938                         entity->variable.elf_visibility = default_visibility;
3939                         entity->variable.thread_local   = specifiers->thread_local;
3940
3941                         if (env.symbol != NULL) {
3942                                 if (specifiers->is_inline && is_type_valid(type)) {
3943                                         errorf(&env.source_position,
3944                                                         "variable '%Y' declared 'inline'", env.symbol);
3945                                 }
3946
3947                                 bool invalid_storage_class = false;
3948                                 if (current_scope == file_scope) {
3949                                         if (specifiers->storage_class != STORAGE_CLASS_EXTERN &&
3950                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
3951                                                         specifiers->storage_class != STORAGE_CLASS_STATIC) {
3952                                                 invalid_storage_class = true;
3953                                         }
3954                                 } else {
3955                                         if (specifiers->thread_local &&
3956                                                         specifiers->storage_class == STORAGE_CLASS_NONE) {
3957                                                 invalid_storage_class = true;
3958                                         }
3959                                 }
3960                                 if (invalid_storage_class) {
3961                                         errorf(&env.source_position,
3962                                                         "invalid storage class for variable '%Y'", env.symbol);
3963                                 }
3964                         }
3965                 }
3966
3967                 entity->base.source_position   = env.symbol != NULL ? env.source_position : specifiers->source_position;
3968                 entity->declaration.type       = orig_type;
3969                 entity->declaration.alignment  = get_type_alignment(orig_type);
3970                 entity->declaration.modifiers  = env.modifiers;
3971                 entity->declaration.attributes = attributes;
3972
3973                 storage_class_t storage_class = specifiers->storage_class;
3974                 entity->declaration.declared_storage_class = storage_class;
3975
3976                 if (storage_class == STORAGE_CLASS_NONE && current_function != NULL)
3977                         storage_class = STORAGE_CLASS_AUTO;
3978                 entity->declaration.storage_class = storage_class;
3979         }
3980
3981         if (attributes != NULL) {
3982                 handle_entity_attributes(attributes, entity);
3983         }
3984
3985         return entity;
3986 }
3987
3988 static type_t *parse_abstract_declarator(type_t *base_type)
3989 {
3990         parse_declarator_env_t env;
3991         memset(&env, 0, sizeof(env));
3992         env.may_be_abstract = true;
3993         env.must_be_abstract = true;
3994
3995         construct_type_t *construct_type = parse_inner_declarator(&env);
3996
3997         type_t *result = construct_declarator_type(construct_type, base_type);
3998         if (construct_type != NULL) {
3999                 obstack_free(&temp_obst, construct_type);
4000         }
4001         result = handle_type_attributes(env.attributes, result);
4002
4003         return result;
4004 }
4005
4006 /**
4007  * Check if the declaration of main is suspicious.  main should be a
4008  * function with external linkage, returning int, taking either zero
4009  * arguments, two, or three arguments of appropriate types, ie.
4010  *
4011  * int main([ int argc, char **argv [, char **env ] ]).
4012  *
4013  * @param decl    the declaration to check
4014  * @param type    the function type of the declaration
4015  */
4016 static void check_main(const entity_t *entity)
4017 {
4018         const source_position_t *pos = &entity->base.source_position;
4019         if (entity->kind != ENTITY_FUNCTION) {
4020                 warningf(pos, "'main' is not a function");
4021                 return;
4022         }
4023
4024         if (entity->declaration.storage_class == STORAGE_CLASS_STATIC) {
4025                 warningf(pos, "'main' is normally a non-static function");
4026         }
4027
4028         type_t *type = skip_typeref(entity->declaration.type);
4029         assert(is_type_function(type));
4030
4031         function_type_t *func_type = &type->function;
4032         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4033                 warningf(pos, "return type of 'main' should be 'int', but is '%T'",
4034                          func_type->return_type);
4035         }
4036         const function_parameter_t *parm = func_type->parameters;
4037         if (parm != NULL) {
4038                 type_t *const first_type        = skip_typeref(parm->type);
4039                 type_t *const first_type_unqual = get_unqualified_type(first_type);
4040                 if (!types_compatible(first_type_unqual, type_int)) {
4041                         warningf(pos,
4042                                  "first argument of 'main' should be 'int', but is '%T'",
4043                                  parm->type);
4044                 }
4045                 parm = parm->next;
4046                 if (parm != NULL) {
4047                         type_t *const second_type = skip_typeref(parm->type);
4048                         type_t *const second_type_unqual
4049                                 = get_unqualified_type(second_type);
4050                         if (!types_compatible(second_type_unqual, type_char_ptr_ptr)) {
4051                                 warningf(pos, "second argument of 'main' should be 'char**', but is '%T'",
4052                                          parm->type);
4053                         }
4054                         parm = parm->next;
4055                         if (parm != NULL) {
4056                                 type_t *const third_type = skip_typeref(parm->type);
4057                                 type_t *const third_type_unqual
4058                                         = get_unqualified_type(third_type);
4059                                 if (!types_compatible(third_type_unqual, type_char_ptr_ptr)) {
4060                                         warningf(pos, "third argument of 'main' should be 'char**', but is '%T'",
4061                                                  parm->type);
4062                                 }
4063                                 parm = parm->next;
4064                                 if (parm != NULL)
4065                                         goto warn_arg_count;
4066                         }
4067                 } else {
4068 warn_arg_count:
4069                         warningf(pos, "'main' takes only zero, two or three arguments");
4070                 }
4071         }
4072 }
4073
4074 /**
4075  * Check if a symbol is the equal to "main".
4076  */
4077 static bool is_sym_main(const symbol_t *const sym)
4078 {
4079         return strcmp(sym->string, "main") == 0;
4080 }
4081
4082 static void error_redefined_as_different_kind(const source_position_t *pos,
4083                 const entity_t *old, entity_kind_t new_kind)
4084 {
4085         errorf(pos, "redeclaration of %s '%Y' as %s (declared %P)",
4086                get_entity_kind_name(old->kind), old->base.symbol,
4087                get_entity_kind_name(new_kind), &old->base.source_position);
4088 }
4089
4090 static bool is_entity_valid(entity_t *const ent)
4091 {
4092         if (is_declaration(ent)) {
4093                 return is_type_valid(skip_typeref(ent->declaration.type));
4094         } else if (ent->kind == ENTITY_TYPEDEF) {
4095                 return is_type_valid(skip_typeref(ent->typedefe.type));
4096         }
4097         return true;
4098 }
4099
4100 static bool contains_attribute(const attribute_t *list, const attribute_t *attr)
4101 {
4102         for (const attribute_t *tattr = list; tattr != NULL; tattr = tattr->next) {
4103                 if (attributes_equal(tattr, attr))
4104                         return true;
4105         }
4106         return false;
4107 }
4108
4109 /**
4110  * test wether new_list contains any attributes not included in old_list
4111  */
4112 static bool has_new_attributes(const attribute_t *old_list,
4113                                const attribute_t *new_list)
4114 {
4115         for (const attribute_t *attr = new_list; attr != NULL; attr = attr->next) {
4116                 if (!contains_attribute(old_list, attr))
4117                         return true;
4118         }
4119         return false;
4120 }
4121
4122 /**
4123  * Merge in attributes from an attribute list (probably from a previous
4124  * declaration with the same name). Warning: destroys the old structure
4125  * of the attribute list - don't reuse attributes after this call.
4126  */
4127 static void merge_in_attributes(declaration_t *decl, attribute_t *attributes)
4128 {
4129         attribute_t *next;
4130         for (attribute_t *attr = attributes; attr != NULL; attr = next) {
4131                 next = attr->next;
4132                 if (contains_attribute(decl->attributes, attr))
4133                         continue;
4134
4135                 /* move attribute to new declarations attributes list */
4136                 attr->next       = decl->attributes;
4137                 decl->attributes = attr;
4138         }
4139 }
4140
4141 /**
4142  * record entities for the NAMESPACE_NORMAL, and produce error messages/warnings
4143  * for various problems that occur for multiple definitions
4144  */
4145 entity_t *record_entity(entity_t *entity, const bool is_definition)
4146 {
4147         const symbol_t *const    symbol  = entity->base.symbol;
4148         const namespace_tag_t    namespc = (namespace_tag_t)entity->base.namespc;
4149         const source_position_t *pos     = &entity->base.source_position;
4150
4151         /* can happen in error cases */
4152         if (symbol == NULL)
4153                 return entity;
4154
4155         entity_t *const previous_entity = get_entity(symbol, namespc);
4156         /* pushing the same entity twice will break the stack structure */
4157         assert(previous_entity != entity);
4158
4159         if (entity->kind == ENTITY_FUNCTION) {
4160                 type_t *const orig_type = entity->declaration.type;
4161                 type_t *const type      = skip_typeref(orig_type);
4162
4163                 assert(is_type_function(type));
4164                 if (type->function.unspecified_parameters &&
4165                                 warning.strict_prototypes &&
4166                                 previous_entity == NULL) {
4167                         warningf(pos, "function declaration '%#T' is not a prototype",
4168                                          orig_type, symbol);
4169                 }
4170
4171                 if (warning.main && current_scope == file_scope
4172                                 && is_sym_main(symbol)) {
4173                         check_main(entity);
4174                 }
4175         }
4176
4177         if (is_declaration(entity) &&
4178                         warning.nested_externs &&
4179                         entity->declaration.storage_class == STORAGE_CLASS_EXTERN &&
4180                         current_scope != file_scope) {
4181                 warningf(pos, "nested extern declaration of '%#T'",
4182                          entity->declaration.type, symbol);
4183         }
4184
4185         if (previous_entity != NULL) {
4186                 if (previous_entity->base.parent_scope == &current_function->parameters &&
4187                                 previous_entity->base.parent_scope->depth + 1 == current_scope->depth) {
4188                         assert(previous_entity->kind == ENTITY_PARAMETER);
4189                         errorf(pos,
4190                                         "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
4191                                         entity->declaration.type, symbol,
4192                                         previous_entity->declaration.type, symbol,
4193                                         &previous_entity->base.source_position);
4194                         goto finish;
4195                 }
4196
4197                 if (previous_entity->base.parent_scope == current_scope) {
4198                         if (previous_entity->kind != entity->kind) {
4199                                 if (is_entity_valid(previous_entity) && is_entity_valid(entity)) {
4200                                         error_redefined_as_different_kind(pos, previous_entity,
4201                                                         entity->kind);
4202                                 }
4203                                 goto finish;
4204                         }
4205                         if (previous_entity->kind == ENTITY_ENUM_VALUE) {
4206                                 errorf(pos, "redeclaration of enum entry '%Y' (declared %P)",
4207                                                 symbol, &previous_entity->base.source_position);
4208                                 goto finish;
4209                         }
4210                         if (previous_entity->kind == ENTITY_TYPEDEF) {
4211                                 /* TODO: C++ allows this for exactly the same type */
4212                                 errorf(pos, "redefinition of typedef '%Y' (declared %P)",
4213                                                 symbol, &previous_entity->base.source_position);
4214                                 goto finish;
4215                         }
4216
4217                         /* at this point we should have only VARIABLES or FUNCTIONS */
4218                         assert(is_declaration(previous_entity) && is_declaration(entity));
4219
4220                         declaration_t *const prev_decl = &previous_entity->declaration;
4221                         declaration_t *const decl      = &entity->declaration;
4222
4223                         /* can happen for K&R style declarations */
4224                         if (prev_decl->type       == NULL             &&
4225                                         previous_entity->kind == ENTITY_PARAMETER &&
4226                                         entity->kind          == ENTITY_PARAMETER) {
4227                                 prev_decl->type                   = decl->type;
4228                                 prev_decl->storage_class          = decl->storage_class;
4229                                 prev_decl->declared_storage_class = decl->declared_storage_class;
4230                                 prev_decl->modifiers              = decl->modifiers;
4231                                 return previous_entity;
4232                         }
4233
4234                         type_t *const orig_type = decl->type;
4235                         assert(orig_type != NULL);
4236                         type_t *const type      = skip_typeref(orig_type);
4237                         type_t *const prev_type = skip_typeref(prev_decl->type);
4238
4239                         if (!types_compatible(type, prev_type)) {
4240                                 errorf(pos,
4241                                                 "declaration '%#T' is incompatible with '%#T' (declared %P)",
4242                                                 orig_type, symbol, prev_decl->type, symbol,
4243                                                 &previous_entity->base.source_position);
4244                         } else {
4245                                 unsigned old_storage_class = prev_decl->storage_class;
4246
4247                                 if (warning.redundant_decls               &&
4248                                                 is_definition                     &&
4249                                                 !prev_decl->used                  &&
4250                                                 !(prev_decl->modifiers & DM_USED) &&
4251                                                 prev_decl->storage_class == STORAGE_CLASS_STATIC) {
4252                                         warningf(&previous_entity->base.source_position,
4253                                                         "unnecessary static forward declaration for '%#T'",
4254                                                         prev_decl->type, symbol);
4255                                 }
4256
4257                                 storage_class_t new_storage_class = decl->storage_class;
4258
4259                                 /* pretend no storage class means extern for function
4260                                  * declarations (except if the previous declaration is neither
4261                                  * none nor extern) */
4262                                 if (entity->kind == ENTITY_FUNCTION) {
4263                                         /* the previous declaration could have unspecified parameters or
4264                                          * be a typedef, so use the new type */
4265                                         if (prev_type->function.unspecified_parameters || is_definition)
4266                                                 prev_decl->type = type;
4267
4268                                         switch (old_storage_class) {
4269                                                 case STORAGE_CLASS_NONE:
4270                                                         old_storage_class = STORAGE_CLASS_EXTERN;
4271                                                         /* FALLTHROUGH */
4272
4273                                                 case STORAGE_CLASS_EXTERN:
4274                                                         if (is_definition) {
4275                                                                 if (warning.missing_prototypes &&
4276                                                                                 prev_type->function.unspecified_parameters &&
4277                                                                                 !is_sym_main(symbol)) {
4278                                                                         warningf(pos, "no previous prototype for '%#T'",
4279                                                                                         orig_type, symbol);
4280                                                                 }
4281                                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4282                                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4283                                                         }
4284                                                         break;
4285
4286                                                 default:
4287                                                         break;
4288                                         }
4289                                 } else if (is_type_incomplete(prev_type)) {
4290                                         prev_decl->type = type;
4291                                 }
4292
4293                                 if (old_storage_class == STORAGE_CLASS_EXTERN &&
4294                                                 new_storage_class == STORAGE_CLASS_EXTERN) {
4295
4296 warn_redundant_declaration: ;
4297                                         bool has_new_attrs
4298                                                 = has_new_attributes(prev_decl->attributes,
4299                                                                      decl->attributes);
4300                                         if (has_new_attrs) {
4301                                                 merge_in_attributes(decl, prev_decl->attributes);
4302                                         } else if (!is_definition        &&
4303                                                         warning.redundant_decls  &&
4304                                                         is_type_valid(prev_type) &&
4305                                                         strcmp(previous_entity->base.source_position.input_name,
4306                                                                 "<builtin>") != 0) {
4307                                                 warningf(pos,
4308                                                          "redundant declaration for '%Y' (declared %P)",
4309                                                          symbol, &previous_entity->base.source_position);
4310                                         }
4311                                 } else if (current_function == NULL) {
4312                                         if (old_storage_class != STORAGE_CLASS_STATIC &&
4313                                                         new_storage_class == STORAGE_CLASS_STATIC) {
4314                                                 errorf(pos,
4315                                                        "static declaration of '%Y' follows non-static declaration (declared %P)",
4316                                                        symbol, &previous_entity->base.source_position);
4317                                         } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4318                                                 prev_decl->storage_class          = STORAGE_CLASS_NONE;
4319                                                 prev_decl->declared_storage_class = STORAGE_CLASS_NONE;
4320                                         } else {
4321                                                 /* ISO/IEC 14882:1998(E) §C.1.2:1 */
4322                                                 if (c_mode & _CXX)
4323                                                         goto error_redeclaration;
4324                                                 goto warn_redundant_declaration;
4325                                         }
4326                                 } else if (is_type_valid(prev_type)) {
4327                                         if (old_storage_class == new_storage_class) {
4328 error_redeclaration:
4329                                                 errorf(pos, "redeclaration of '%Y' (declared %P)",
4330                                                                 symbol, &previous_entity->base.source_position);
4331                                         } else {
4332                                                 errorf(pos,
4333                                                                 "redeclaration of '%Y' with different linkage (declared %P)",
4334                                                                 symbol, &previous_entity->base.source_position);
4335                                         }
4336                                 }
4337                         }
4338
4339                         prev_decl->modifiers |= decl->modifiers;
4340                         if (entity->kind == ENTITY_FUNCTION) {
4341                                 previous_entity->function.is_inline |= entity->function.is_inline;
4342                         }
4343                         return previous_entity;
4344                 }
4345
4346                 if (warning.shadow ||
4347                                 (warning.shadow_local && previous_entity->base.parent_scope != file_scope)) {
4348                         warningf(pos, "%s '%Y' shadows %s (declared %P)",
4349                                         get_entity_kind_name(entity->kind), symbol,
4350                                         get_entity_kind_name(previous_entity->kind),
4351                                         &previous_entity->base.source_position);
4352                 }
4353         }
4354
4355         if (entity->kind == ENTITY_FUNCTION) {
4356                 if (is_definition &&
4357                                 entity->declaration.storage_class != STORAGE_CLASS_STATIC) {
4358                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4359                                 warningf(pos, "no previous prototype for '%#T'",
4360                                          entity->declaration.type, symbol);
4361                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4362                                 warningf(pos, "no previous declaration for '%#T'",
4363                                          entity->declaration.type, symbol);
4364                         }
4365                 }
4366         } else if (warning.missing_declarations &&
4367                         entity->kind == ENTITY_VARIABLE &&
4368                         current_scope == file_scope) {
4369                 declaration_t *declaration = &entity->declaration;
4370                 if (declaration->storage_class == STORAGE_CLASS_NONE) {
4371                         warningf(pos, "no previous declaration for '%#T'",
4372                                  declaration->type, symbol);
4373                 }
4374         }
4375
4376 finish:
4377         assert(entity->base.parent_scope == NULL);
4378         assert(current_scope != NULL);
4379
4380         entity->base.parent_scope = current_scope;
4381         environment_push(entity);
4382         append_entity(current_scope, entity);
4383
4384         return entity;
4385 }
4386
4387 static void parser_error_multiple_definition(entity_t *entity,
4388                 const source_position_t *source_position)
4389 {
4390         errorf(source_position, "multiple definition of '%Y' (declared %P)",
4391                entity->base.symbol, &entity->base.source_position);
4392 }
4393
4394 static bool is_declaration_specifier(const token_t *token)
4395 {
4396         switch (token->type) {
4397                 DECLARATION_START
4398                         return true;
4399                 case T_IDENTIFIER:
4400                         return is_typedef_symbol(token->symbol);
4401
4402                 default:
4403                         return false;
4404         }
4405 }
4406
4407 static void parse_init_declarator_rest(entity_t *entity)
4408 {
4409         type_t *orig_type = type_error_type;
4410
4411         if (entity->base.kind == ENTITY_TYPEDEF) {
4412                 errorf(&entity->base.source_position,
4413                        "typedef '%Y' is initialized (use __typeof__ instead)",
4414                        entity->base.symbol);
4415         } else {
4416                 assert(is_declaration(entity));
4417                 orig_type = entity->declaration.type;
4418         }
4419
4420         type_t *type = skip_typeref(orig_type);
4421
4422         if (entity->kind == ENTITY_VARIABLE
4423                         && entity->variable.initializer != NULL) {
4424                 parser_error_multiple_definition(entity, HERE);
4425         }
4426         eat('=');
4427
4428         declaration_t *const declaration = &entity->declaration;
4429         bool must_be_constant = false;
4430         if (declaration->storage_class == STORAGE_CLASS_STATIC ||
4431             entity->base.parent_scope  == file_scope) {
4432                 must_be_constant = true;
4433         }
4434
4435         if (is_type_function(type)) {
4436                 errorf(&entity->base.source_position,
4437                        "function '%#T' is initialized like a variable",
4438                        orig_type, entity->base.symbol);
4439                 orig_type = type_error_type;
4440         }
4441
4442         parse_initializer_env_t env;
4443         env.type             = orig_type;
4444         env.must_be_constant = must_be_constant;
4445         env.entity           = entity;
4446         current_init_decl    = entity;
4447
4448         initializer_t *initializer = parse_initializer(&env);
4449         current_init_decl = NULL;
4450
4451         if (entity->kind == ENTITY_VARIABLE) {
4452                 /* §6.7.5:22  array initializers for arrays with unknown size
4453                  * determine the array type size */
4454                 declaration->type            = env.type;
4455                 entity->variable.initializer = initializer;
4456         }
4457 }
4458
4459 /* parse rest of a declaration without any declarator */
4460 static void parse_anonymous_declaration_rest(
4461                 const declaration_specifiers_t *specifiers)
4462 {
4463         eat(';');
4464         anonymous_entity = NULL;
4465
4466         if (warning.other) {
4467                 if (specifiers->storage_class != STORAGE_CLASS_NONE ||
4468                                 specifiers->thread_local) {
4469                         warningf(&specifiers->source_position,
4470                                  "useless storage class in empty declaration");
4471                 }
4472
4473                 type_t *type = specifiers->type;
4474                 switch (type->kind) {
4475                         case TYPE_COMPOUND_STRUCT:
4476                         case TYPE_COMPOUND_UNION: {
4477                                 if (type->compound.compound->base.symbol == NULL) {
4478                                         warningf(&specifiers->source_position,
4479                                                  "unnamed struct/union that defines no instances");
4480                                 }
4481                                 break;
4482                         }
4483
4484                         case TYPE_ENUM:
4485                                 break;
4486
4487                         default:
4488                                 warningf(&specifiers->source_position, "empty declaration");
4489                                 break;
4490                 }
4491         }
4492 }
4493
4494 static void check_variable_type_complete(entity_t *ent)
4495 {
4496         if (ent->kind != ENTITY_VARIABLE)
4497                 return;
4498
4499         /* §6.7:7  If an identifier for an object is declared with no linkage, the
4500          *         type for the object shall be complete [...] */
4501         declaration_t *decl = &ent->declaration;
4502         if (decl->storage_class == STORAGE_CLASS_EXTERN ||
4503                         decl->storage_class == STORAGE_CLASS_STATIC)
4504                 return;
4505
4506         type_t *const orig_type = decl->type;
4507         type_t *const type      = skip_typeref(orig_type);
4508         if (!is_type_incomplete(type))
4509                 return;
4510
4511         /* §6.9.2:2 and §6.9.2:5: At the end of the translation incomplete arrays
4512          * are given length one. */
4513         if (is_type_array(type) && ent->base.parent_scope == file_scope) {
4514                 ARR_APP1(declaration_t*, incomplete_arrays, decl);
4515                 return;
4516         }
4517
4518         errorf(&ent->base.source_position, "variable '%#T' has incomplete type",
4519                         orig_type, ent->base.symbol);
4520 }
4521
4522
4523 static void parse_declaration_rest(entity_t *ndeclaration,
4524                 const declaration_specifiers_t *specifiers,
4525                 parsed_declaration_func         finished_declaration,
4526                 declarator_flags_t              flags)
4527 {
4528         add_anchor_token(';');
4529         add_anchor_token(',');
4530         while (true) {
4531                 entity_t *entity = finished_declaration(ndeclaration, token.type == '=');
4532
4533                 if (token.type == '=') {
4534                         parse_init_declarator_rest(entity);
4535                 } else if (entity->kind == ENTITY_VARIABLE) {
4536                         /* ISO/IEC 14882:1998(E) §8.5.3:3  The initializer can be omitted
4537                          * [...] where the extern specifier is explicitly used. */
4538                         declaration_t *decl = &entity->declaration;
4539                         if (decl->storage_class != STORAGE_CLASS_EXTERN) {
4540                                 type_t *type = decl->type;
4541                                 if (is_type_reference(skip_typeref(type))) {
4542                                         errorf(&entity->base.source_position,
4543                                                         "reference '%#T' must be initialized",
4544                                                         type, entity->base.symbol);
4545                                 }
4546                         }
4547                 }
4548
4549                 check_variable_type_complete(entity);
4550
4551                 if (!next_if(','))
4552                         break;
4553
4554                 add_anchor_token('=');
4555                 ndeclaration = parse_declarator(specifiers, flags);
4556                 rem_anchor_token('=');
4557         }
4558         expect(';', end_error);
4559
4560 end_error:
4561         anonymous_entity = NULL;
4562         rem_anchor_token(';');
4563         rem_anchor_token(',');
4564 }
4565
4566 static entity_t *finished_kr_declaration(entity_t *entity, bool is_definition)
4567 {
4568         symbol_t *symbol = entity->base.symbol;
4569         if (symbol == NULL)
4570                 return entity;
4571
4572         assert(entity->base.namespc == NAMESPACE_NORMAL);
4573         entity_t *previous_entity = get_entity(symbol, NAMESPACE_NORMAL);
4574         if (previous_entity == NULL
4575                         || previous_entity->base.parent_scope != current_scope) {
4576                 errorf(&entity->base.source_position, "expected declaration of a function parameter, found '%Y'",
4577                        symbol);
4578                 return entity;
4579         }
4580
4581         if (is_definition) {
4582                 errorf(HERE, "parameter '%Y' is initialised", entity->base.symbol);
4583         }
4584
4585         return record_entity(entity, false);
4586 }
4587
4588 static void parse_declaration(parsed_declaration_func finished_declaration,
4589                               declarator_flags_t      flags)
4590 {
4591         add_anchor_token(';');
4592         declaration_specifiers_t specifiers;
4593         parse_declaration_specifiers(&specifiers);
4594         rem_anchor_token(';');
4595
4596         if (token.type == ';') {
4597                 parse_anonymous_declaration_rest(&specifiers);
4598         } else {
4599                 entity_t *entity = parse_declarator(&specifiers, flags);
4600                 parse_declaration_rest(entity, &specifiers, finished_declaration, flags);
4601         }
4602 }
4603
4604 /* §6.5.2.2:6 */
4605 static type_t *get_default_promoted_type(type_t *orig_type)
4606 {
4607         type_t *result = orig_type;
4608
4609         type_t *type = skip_typeref(orig_type);
4610         if (is_type_integer(type)) {
4611                 result = promote_integer(type);
4612         } else if (is_type_atomic(type, ATOMIC_TYPE_FLOAT)) {
4613                 result = type_double;
4614         }
4615
4616         return result;
4617 }
4618
4619 static void parse_kr_declaration_list(entity_t *entity)
4620 {
4621         if (entity->kind != ENTITY_FUNCTION)
4622                 return;
4623
4624         type_t *type = skip_typeref(entity->declaration.type);
4625         assert(is_type_function(type));
4626         if (!type->function.kr_style_parameters)
4627                 return;
4628
4629         add_anchor_token('{');
4630
4631         /* push function parameters */
4632         size_t const  top       = environment_top();
4633         scope_t      *old_scope = scope_push(&entity->function.parameters);
4634
4635         entity_t *parameter = entity->function.parameters.entities;
4636         for ( ; parameter != NULL; parameter = parameter->base.next) {
4637                 assert(parameter->base.parent_scope == NULL);
4638                 parameter->base.parent_scope = current_scope;
4639                 environment_push(parameter);
4640         }
4641
4642         /* parse declaration list */
4643         for (;;) {
4644                 switch (token.type) {
4645                         DECLARATION_START
4646                         case T___extension__:
4647                         /* This covers symbols, which are no type, too, and results in
4648                          * better error messages.  The typical cases are misspelled type
4649                          * names and missing includes. */
4650                         case T_IDENTIFIER:
4651                                 parse_declaration(finished_kr_declaration, DECL_IS_PARAMETER);
4652                                 break;
4653                         default:
4654                                 goto decl_list_end;
4655                 }
4656         }
4657 decl_list_end:
4658
4659         /* pop function parameters */
4660         assert(current_scope == &entity->function.parameters);
4661         scope_pop(old_scope);
4662         environment_pop_to(top);
4663
4664         /* update function type */
4665         type_t *new_type = duplicate_type(type);
4666
4667         function_parameter_t  *parameters = NULL;
4668         function_parameter_t **anchor     = &parameters;
4669
4670         /* did we have an earlier prototype? */
4671         entity_t *proto_type = get_entity(entity->base.symbol, NAMESPACE_NORMAL);
4672         if (proto_type != NULL && proto_type->kind != ENTITY_FUNCTION)
4673                 proto_type = NULL;
4674
4675         function_parameter_t *proto_parameter = NULL;
4676         if (proto_type != NULL) {
4677                 type_t *proto_type_type = proto_type->declaration.type;
4678                 proto_parameter         = proto_type_type->function.parameters;
4679                 /* If a K&R function definition has a variadic prototype earlier, then
4680                  * make the function definition variadic, too. This should conform to
4681                  * §6.7.5.3:15 and §6.9.1:8. */
4682                 new_type->function.variadic = proto_type_type->function.variadic;
4683         } else {
4684                 /* §6.9.1.7: A K&R style parameter list does NOT act as a function
4685                  * prototype */
4686                 new_type->function.unspecified_parameters = true;
4687         }
4688
4689         bool need_incompatible_warning = false;
4690         parameter = entity->function.parameters.entities;
4691         for (; parameter != NULL; parameter = parameter->base.next,
4692                         proto_parameter =
4693                                 proto_parameter == NULL ? NULL : proto_parameter->next) {
4694                 if (parameter->kind != ENTITY_PARAMETER)
4695                         continue;
4696
4697                 type_t *parameter_type = parameter->declaration.type;
4698                 if (parameter_type == NULL) {
4699                         source_position_t const* const pos = &parameter->base.source_position;
4700                         if (strict_mode) {
4701                                 errorf(pos, "no type specified for function parameter '%Y'", parameter->base.symbol);
4702                                 parameter_type = type_error_type;
4703                         } else {
4704                                 if (warning.implicit_int) {
4705                                         warningf(pos, "no type specified for function parameter '%Y', using 'int'", parameter->base.symbol);
4706                                 }
4707                                 parameter_type = type_int;
4708                         }
4709                         parameter->declaration.type = parameter_type;
4710                 }
4711
4712                 semantic_parameter_incomplete(parameter);
4713
4714                 /* we need the default promoted types for the function type */
4715                 type_t *not_promoted = parameter_type;
4716                 parameter_type       = get_default_promoted_type(parameter_type);
4717
4718                 /* gcc special: if the type of the prototype matches the unpromoted
4719                  * type don't promote */
4720                 if (!strict_mode && proto_parameter != NULL) {
4721                         type_t *proto_p_type = skip_typeref(proto_parameter->type);
4722                         type_t *promo_skip   = skip_typeref(parameter_type);
4723                         type_t *param_skip   = skip_typeref(not_promoted);
4724                         if (!types_compatible(proto_p_type, promo_skip)
4725                                 && types_compatible(proto_p_type, param_skip)) {
4726                                 /* don't promote */
4727                                 need_incompatible_warning = true;
4728                                 parameter_type = not_promoted;
4729                         }
4730                 }
4731                 function_parameter_t *const parameter
4732                         = allocate_parameter(parameter_type);
4733
4734                 *anchor = parameter;
4735                 anchor  = &parameter->next;
4736         }
4737
4738         new_type->function.parameters = parameters;
4739         new_type = identify_new_type(new_type);
4740
4741         if (warning.other && need_incompatible_warning) {
4742                 type_t *proto_type_type = proto_type->declaration.type;
4743                 warningf(&entity->base.source_position,
4744                          "declaration '%#T' is incompatible with '%#T' (declared %P)",
4745                          proto_type_type, proto_type->base.symbol,
4746                          new_type, entity->base.symbol,
4747                          &proto_type->base.source_position);
4748         }
4749
4750         entity->declaration.type = new_type;
4751
4752         rem_anchor_token('{');
4753 }
4754
4755 static bool first_err = true;
4756
4757 /**
4758  * When called with first_err set, prints the name of the current function,
4759  * else does noting.
4760  */
4761 static void print_in_function(void)
4762 {
4763         if (first_err) {
4764                 first_err = false;
4765                 diagnosticf("%s: In function '%Y':\n",
4766                             current_function->base.base.source_position.input_name,
4767                             current_function->base.base.symbol);
4768         }
4769 }
4770
4771 /**
4772  * Check if all labels are defined in the current function.
4773  * Check if all labels are used in the current function.
4774  */
4775 static void check_labels(void)
4776 {
4777         for (const goto_statement_t *goto_statement = goto_first;
4778             goto_statement != NULL;
4779             goto_statement = goto_statement->next) {
4780                 /* skip computed gotos */
4781                 if (goto_statement->expression != NULL)
4782                         continue;
4783
4784                 label_t *label = goto_statement->label;
4785                 if (label->base.source_position.input_name == NULL) {
4786                         print_in_function();
4787                         errorf(&goto_statement->base.source_position,
4788                                "label '%Y' used but not defined", label->base.symbol);
4789                  }
4790         }
4791
4792         if (warning.unused_label) {
4793                 for (const label_statement_t *label_statement = label_first;
4794                          label_statement != NULL;
4795                          label_statement = label_statement->next) {
4796                         label_t *label = label_statement->label;
4797
4798                         if (! label->used) {
4799                                 print_in_function();
4800                                 warningf(&label_statement->base.source_position,
4801                                          "label '%Y' defined but not used", label->base.symbol);
4802                         }
4803                 }
4804         }
4805 }
4806
4807 static void warn_unused_entity(entity_t *entity, entity_t *last)
4808 {
4809         entity_t const *const end = last != NULL ? last->base.next : NULL;
4810         for (; entity != end; entity = entity->base.next) {
4811                 if (!is_declaration(entity))
4812                         continue;
4813
4814                 declaration_t *declaration = &entity->declaration;
4815                 if (declaration->implicit)
4816                         continue;
4817
4818                 if (!declaration->used) {
4819                         print_in_function();
4820                         const char *what = get_entity_kind_name(entity->kind);
4821                         warningf(&entity->base.source_position, "%s '%Y' is unused",
4822                                  what, entity->base.symbol);
4823                 } else if (entity->kind == ENTITY_VARIABLE && !entity->variable.read) {
4824                         print_in_function();
4825                         const char *what = get_entity_kind_name(entity->kind);
4826                         warningf(&entity->base.source_position, "%s '%Y' is never read",
4827                                  what, entity->base.symbol);
4828                 }
4829         }
4830 }
4831
4832 static void check_unused_variables(statement_t *const stmt, void *const env)
4833 {
4834         (void)env;
4835
4836         switch (stmt->kind) {
4837                 case STATEMENT_DECLARATION: {
4838                         declaration_statement_t const *const decls = &stmt->declaration;
4839                         warn_unused_entity(decls->declarations_begin,
4840                                            decls->declarations_end);
4841                         return;
4842                 }
4843
4844                 case STATEMENT_FOR:
4845                         warn_unused_entity(stmt->fors.scope.entities, NULL);
4846                         return;
4847
4848                 default:
4849                         return;
4850         }
4851 }
4852
4853 /**
4854  * Check declarations of current_function for unused entities.
4855  */
4856 static void check_declarations(void)
4857 {
4858         if (warning.unused_parameter) {
4859                 const scope_t *scope = &current_function->parameters;
4860
4861                 /* do not issue unused warnings for main */
4862                 if (!is_sym_main(current_function->base.base.symbol)) {
4863                         warn_unused_entity(scope->entities, NULL);
4864                 }
4865         }
4866         if (warning.unused_variable) {
4867                 walk_statements(current_function->statement, check_unused_variables,
4868                                 NULL);
4869         }
4870 }
4871
4872 static int determine_truth(expression_t const* const cond)
4873 {
4874         return
4875                 is_constant_expression(cond) != EXPR_CLASS_CONSTANT ? 0 :
4876                 fold_constant_to_bool(cond)                         ? 1 :
4877                 -1;
4878 }
4879
4880 static void check_reachable(statement_t *);
4881 static bool reaches_end;
4882
4883 static bool expression_returns(expression_t const *const expr)
4884 {
4885         switch (expr->kind) {
4886                 case EXPR_CALL: {
4887                         expression_t const *const func = expr->call.function;
4888                         if (func->kind == EXPR_REFERENCE) {
4889                                 entity_t *entity = func->reference.entity;
4890                                 if (entity->kind == ENTITY_FUNCTION
4891                                                 && entity->declaration.modifiers & DM_NORETURN)
4892                                         return false;
4893                         }
4894
4895                         if (!expression_returns(func))
4896                                 return false;
4897
4898                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
4899                                 if (!expression_returns(arg->expression))
4900                                         return false;
4901                         }
4902
4903                         return true;
4904                 }
4905
4906                 case EXPR_REFERENCE:
4907                 case EXPR_REFERENCE_ENUM_VALUE:
4908                 EXPR_LITERAL_CASES
4909                 case EXPR_STRING_LITERAL:
4910                 case EXPR_WIDE_STRING_LITERAL:
4911                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
4912                 case EXPR_LABEL_ADDRESS:
4913                 case EXPR_CLASSIFY_TYPE:
4914                 case EXPR_SIZEOF: // TODO handle obscure VLA case
4915                 case EXPR_ALIGNOF:
4916                 case EXPR_FUNCNAME:
4917                 case EXPR_BUILTIN_CONSTANT_P:
4918                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P:
4919                 case EXPR_OFFSETOF:
4920                 case EXPR_INVALID:
4921                         return true;
4922
4923                 case EXPR_STATEMENT: {
4924                         bool old_reaches_end = reaches_end;
4925                         reaches_end = false;
4926                         check_reachable(expr->statement.statement);
4927                         bool returns = reaches_end;
4928                         reaches_end = old_reaches_end;
4929                         return returns;
4930                 }
4931
4932                 case EXPR_CONDITIONAL:
4933                         // TODO handle constant expression
4934
4935                         if (!expression_returns(expr->conditional.condition))
4936                                 return false;
4937
4938                         if (expr->conditional.true_expression != NULL
4939                                         && expression_returns(expr->conditional.true_expression))
4940                                 return true;
4941
4942                         return expression_returns(expr->conditional.false_expression);
4943
4944                 case EXPR_SELECT:
4945                         return expression_returns(expr->select.compound);
4946
4947                 case EXPR_ARRAY_ACCESS:
4948                         return
4949                                 expression_returns(expr->array_access.array_ref) &&
4950                                 expression_returns(expr->array_access.index);
4951
4952                 case EXPR_VA_START:
4953                         return expression_returns(expr->va_starte.ap);
4954
4955                 case EXPR_VA_ARG:
4956                         return expression_returns(expr->va_arge.ap);
4957
4958                 case EXPR_VA_COPY:
4959                         return expression_returns(expr->va_copye.src);
4960
4961                 EXPR_UNARY_CASES_MANDATORY
4962                         return expression_returns(expr->unary.value);
4963
4964                 case EXPR_UNARY_THROW:
4965                         return false;
4966
4967                 EXPR_BINARY_CASES
4968                         // TODO handle constant lhs of && and ||
4969                         return
4970                                 expression_returns(expr->binary.left) &&
4971                                 expression_returns(expr->binary.right);
4972
4973                 case EXPR_UNKNOWN:
4974                         break;
4975         }
4976
4977         panic("unhandled expression");
4978 }
4979
4980 static bool initializer_returns(initializer_t const *const init)
4981 {
4982         switch (init->kind) {
4983                 case INITIALIZER_VALUE:
4984                         return expression_returns(init->value.value);
4985
4986                 case INITIALIZER_LIST: {
4987                         initializer_t * const*       i       = init->list.initializers;
4988                         initializer_t * const* const end     = i + init->list.len;
4989                         bool                         returns = true;
4990                         for (; i != end; ++i) {
4991                                 if (!initializer_returns(*i))
4992                                         returns = false;
4993                         }
4994                         return returns;
4995                 }
4996
4997                 case INITIALIZER_STRING:
4998                 case INITIALIZER_WIDE_STRING:
4999                 case INITIALIZER_DESIGNATOR: // designators have no payload
5000                         return true;
5001         }
5002         panic("unhandled initializer");
5003 }
5004
5005 static bool noreturn_candidate;
5006
5007 static void check_reachable(statement_t *const stmt)
5008 {
5009         if (stmt->base.reachable)
5010                 return;
5011         if (stmt->kind != STATEMENT_DO_WHILE)
5012                 stmt->base.reachable = true;
5013
5014         statement_t *last = stmt;
5015         statement_t *next;
5016         switch (stmt->kind) {
5017                 case STATEMENT_INVALID:
5018                 case STATEMENT_EMPTY:
5019                 case STATEMENT_ASM:
5020                         next = stmt->base.next;
5021                         break;
5022
5023                 case STATEMENT_DECLARATION: {
5024                         declaration_statement_t const *const decl = &stmt->declaration;
5025                         entity_t                const *      ent  = decl->declarations_begin;
5026                         entity_t                const *const last = decl->declarations_end;
5027                         if (ent != NULL) {
5028                                 for (;; ent = ent->base.next) {
5029                                         if (ent->kind                 == ENTITY_VARIABLE &&
5030                                                         ent->variable.initializer != NULL            &&
5031                                                         !initializer_returns(ent->variable.initializer)) {
5032                                                 return;
5033                                         }
5034                                         if (ent == last)
5035                                                 break;
5036                                 }
5037                         }
5038                         next = stmt->base.next;
5039                         break;
5040                 }
5041
5042                 case STATEMENT_COMPOUND:
5043                         next = stmt->compound.statements;
5044                         if (next == NULL)
5045                                 next = stmt->base.next;
5046                         break;
5047
5048                 case STATEMENT_RETURN: {
5049                         expression_t const *const val = stmt->returns.value;
5050                         if (val == NULL || expression_returns(val))
5051                                 noreturn_candidate = false;
5052                         return;
5053                 }
5054
5055                 case STATEMENT_IF: {
5056                         if_statement_t const *const ifs  = &stmt->ifs;
5057                         expression_t   const *const cond = ifs->condition;
5058
5059                         if (!expression_returns(cond))
5060                                 return;
5061
5062                         int const val = determine_truth(cond);
5063
5064                         if (val >= 0)
5065                                 check_reachable(ifs->true_statement);
5066
5067                         if (val > 0)
5068                                 return;
5069
5070                         if (ifs->false_statement != NULL) {
5071                                 check_reachable(ifs->false_statement);
5072                                 return;
5073                         }
5074
5075                         next = stmt->base.next;
5076                         break;
5077                 }
5078
5079                 case STATEMENT_SWITCH: {
5080                         switch_statement_t const *const switchs = &stmt->switchs;
5081                         expression_t       const *const expr    = switchs->expression;
5082
5083                         if (!expression_returns(expr))
5084                                 return;
5085
5086                         if (is_constant_expression(expr) == EXPR_CLASS_CONSTANT) {
5087                                 long                    const val      = fold_constant_to_int(expr);
5088                                 case_label_statement_t *      defaults = NULL;
5089                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5090                                         if (i->expression == NULL) {
5091                                                 defaults = i;
5092                                                 continue;
5093                                         }
5094
5095                                         if (i->first_case <= val && val <= i->last_case) {
5096                                                 check_reachable((statement_t*)i);
5097                                                 return;
5098                                         }
5099                                 }
5100
5101                                 if (defaults != NULL) {
5102                                         check_reachable((statement_t*)defaults);
5103                                         return;
5104                                 }
5105                         } else {
5106                                 bool has_default = false;
5107                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5108                                         if (i->expression == NULL)
5109                                                 has_default = true;
5110
5111                                         check_reachable((statement_t*)i);
5112                                 }
5113
5114                                 if (has_default)
5115                                         return;
5116                         }
5117
5118                         next = stmt->base.next;
5119                         break;
5120                 }
5121
5122                 case STATEMENT_EXPRESSION: {
5123                         /* Check for noreturn function call */
5124                         expression_t const *const expr = stmt->expression.expression;
5125                         if (!expression_returns(expr))
5126                                 return;
5127
5128                         next = stmt->base.next;
5129                         break;
5130                 }
5131
5132                 case STATEMENT_CONTINUE:
5133                         for (statement_t *parent = stmt;;) {
5134                                 parent = parent->base.parent;
5135                                 if (parent == NULL) /* continue not within loop */
5136                                         return;
5137
5138                                 next = parent;
5139                                 switch (parent->kind) {
5140                                         case STATEMENT_WHILE:    goto continue_while;
5141                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5142                                         case STATEMENT_FOR:      goto continue_for;
5143
5144                                         default: break;
5145                                 }
5146                         }
5147
5148                 case STATEMENT_BREAK:
5149                         for (statement_t *parent = stmt;;) {
5150                                 parent = parent->base.parent;
5151                                 if (parent == NULL) /* break not within loop/switch */
5152                                         return;
5153
5154                                 switch (parent->kind) {
5155                                         case STATEMENT_SWITCH:
5156                                         case STATEMENT_WHILE:
5157                                         case STATEMENT_DO_WHILE:
5158                                         case STATEMENT_FOR:
5159                                                 last = parent;
5160                                                 next = parent->base.next;
5161                                                 goto found_break_parent;
5162
5163                                         default: break;
5164                                 }
5165                         }
5166 found_break_parent:
5167                         break;
5168
5169                 case STATEMENT_GOTO:
5170                         if (stmt->gotos.expression) {
5171                                 if (!expression_returns(stmt->gotos.expression))
5172                                         return;
5173
5174                                 statement_t *parent = stmt->base.parent;
5175                                 if (parent == NULL) /* top level goto */
5176                                         return;
5177                                 next = parent;
5178                         } else {
5179                                 next = stmt->gotos.label->statement;
5180                                 if (next == NULL) /* missing label */
5181                                         return;
5182                         }
5183                         break;
5184
5185                 case STATEMENT_LABEL:
5186                         next = stmt->label.statement;
5187                         break;
5188
5189                 case STATEMENT_CASE_LABEL:
5190                         next = stmt->case_label.statement;
5191                         break;
5192
5193                 case STATEMENT_WHILE: {
5194                         while_statement_t const *const whiles = &stmt->whiles;
5195                         expression_t      const *const cond   = whiles->condition;
5196
5197                         if (!expression_returns(cond))
5198                                 return;
5199
5200                         int const val = determine_truth(cond);
5201
5202                         if (val >= 0)
5203                                 check_reachable(whiles->body);
5204
5205                         if (val > 0)
5206                                 return;
5207
5208                         next = stmt->base.next;
5209                         break;
5210                 }
5211
5212                 case STATEMENT_DO_WHILE:
5213                         next = stmt->do_while.body;
5214                         break;
5215
5216                 case STATEMENT_FOR: {
5217                         for_statement_t *const fors = &stmt->fors;
5218
5219                         if (fors->condition_reachable)
5220                                 return;
5221                         fors->condition_reachable = true;
5222
5223                         expression_t const *const cond = fors->condition;
5224
5225                         int val;
5226                         if (cond == NULL) {
5227                                 val = 1;
5228                         } else if (expression_returns(cond)) {
5229                                 val = determine_truth(cond);
5230                         } else {
5231                                 return;
5232                         }
5233
5234                         if (val >= 0)
5235                                 check_reachable(fors->body);
5236
5237                         if (val > 0)
5238                                 return;
5239
5240                         next = stmt->base.next;
5241                         break;
5242                 }
5243
5244                 case STATEMENT_MS_TRY: {
5245                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5246                         check_reachable(ms_try->try_statement);
5247                         next = ms_try->final_statement;
5248                         break;
5249                 }
5250
5251                 case STATEMENT_LEAVE: {
5252                         statement_t *parent = stmt;
5253                         for (;;) {
5254                                 parent = parent->base.parent;
5255                                 if (parent == NULL) /* __leave not within __try */
5256                                         return;
5257
5258                                 if (parent->kind == STATEMENT_MS_TRY) {
5259                                         last = parent;
5260                                         next = parent->ms_try.final_statement;
5261                                         break;
5262                                 }
5263                         }
5264                         break;
5265                 }
5266
5267                 default:
5268                         panic("invalid statement kind");
5269         }
5270
5271         while (next == NULL) {
5272                 next = last->base.parent;
5273                 if (next == NULL) {
5274                         noreturn_candidate = false;
5275
5276                         type_t *const type = skip_typeref(current_function->base.type);
5277                         assert(is_type_function(type));
5278                         type_t *const ret  = skip_typeref(type->function.return_type);
5279                         if (warning.return_type                    &&
5280                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
5281                             is_type_valid(ret)                     &&
5282                             !is_sym_main(current_function->base.base.symbol)) {
5283                                 warningf(&stmt->base.source_position,
5284                                          "control reaches end of non-void function");
5285                         }
5286                         return;
5287                 }
5288
5289                 switch (next->kind) {
5290                         case STATEMENT_INVALID:
5291                         case STATEMENT_EMPTY:
5292                         case STATEMENT_DECLARATION:
5293                         case STATEMENT_EXPRESSION:
5294                         case STATEMENT_ASM:
5295                         case STATEMENT_RETURN:
5296                         case STATEMENT_CONTINUE:
5297                         case STATEMENT_BREAK:
5298                         case STATEMENT_GOTO:
5299                         case STATEMENT_LEAVE:
5300                                 panic("invalid control flow in function");
5301
5302                         case STATEMENT_COMPOUND:
5303                                 if (next->compound.stmt_expr) {
5304                                         reaches_end = true;
5305                                         return;
5306                                 }
5307                                 /* FALLTHROUGH */
5308                         case STATEMENT_IF:
5309                         case STATEMENT_SWITCH:
5310                         case STATEMENT_LABEL:
5311                         case STATEMENT_CASE_LABEL:
5312                                 last = next;
5313                                 next = next->base.next;
5314                                 break;
5315
5316                         case STATEMENT_WHILE: {
5317 continue_while:
5318                                 if (next->base.reachable)
5319                                         return;
5320                                 next->base.reachable = true;
5321
5322                                 while_statement_t const *const whiles = &next->whiles;
5323                                 expression_t      const *const cond   = whiles->condition;
5324
5325                                 if (!expression_returns(cond))
5326                                         return;
5327
5328                                 int const val = determine_truth(cond);
5329
5330                                 if (val >= 0)
5331                                         check_reachable(whiles->body);
5332
5333                                 if (val > 0)
5334                                         return;
5335
5336                                 last = next;
5337                                 next = next->base.next;
5338                                 break;
5339                         }
5340
5341                         case STATEMENT_DO_WHILE: {
5342 continue_do_while:
5343                                 if (next->base.reachable)
5344                                         return;
5345                                 next->base.reachable = true;
5346
5347                                 do_while_statement_t const *const dw   = &next->do_while;
5348                                 expression_t         const *const cond = dw->condition;
5349
5350                                 if (!expression_returns(cond))
5351                                         return;
5352
5353                                 int const val = determine_truth(cond);
5354
5355                                 if (val >= 0)
5356                                         check_reachable(dw->body);
5357
5358                                 if (val > 0)
5359                                         return;
5360
5361                                 last = next;
5362                                 next = next->base.next;
5363                                 break;
5364                         }
5365
5366                         case STATEMENT_FOR: {
5367 continue_for:;
5368                                 for_statement_t *const fors = &next->fors;
5369
5370                                 fors->step_reachable = true;
5371
5372                                 if (fors->condition_reachable)
5373                                         return;
5374                                 fors->condition_reachable = true;
5375
5376                                 expression_t const *const cond = fors->condition;
5377
5378                                 int val;
5379                                 if (cond == NULL) {
5380                                         val = 1;
5381                                 } else if (expression_returns(cond)) {
5382                                         val = determine_truth(cond);
5383                                 } else {
5384                                         return;
5385                                 }
5386
5387                                 if (val >= 0)
5388                                         check_reachable(fors->body);
5389
5390                                 if (val > 0)
5391                                         return;
5392
5393                                 last = next;
5394                                 next = next->base.next;
5395                                 break;
5396                         }
5397
5398                         case STATEMENT_MS_TRY:
5399                                 last = next;
5400                                 next = next->ms_try.final_statement;
5401                                 break;
5402                 }
5403         }
5404
5405         check_reachable(next);
5406 }
5407
5408 static void check_unreachable(statement_t* const stmt, void *const env)
5409 {
5410         (void)env;
5411
5412         switch (stmt->kind) {
5413                 case STATEMENT_DO_WHILE:
5414                         if (!stmt->base.reachable) {
5415                                 expression_t const *const cond = stmt->do_while.condition;
5416                                 if (determine_truth(cond) >= 0) {
5417                                         warningf(&cond->base.source_position,
5418                                                  "condition of do-while-loop is unreachable");
5419                                 }
5420                         }
5421                         return;
5422
5423                 case STATEMENT_FOR: {
5424                         for_statement_t const* const fors = &stmt->fors;
5425
5426                         // if init and step are unreachable, cond is unreachable, too
5427                         if (!stmt->base.reachable && !fors->step_reachable) {
5428                                 warningf(&stmt->base.source_position, "statement is unreachable");
5429                         } else {
5430                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5431                                         warningf(&fors->initialisation->base.source_position,
5432                                                  "initialisation of for-statement is unreachable");
5433                                 }
5434
5435                                 if (!fors->condition_reachable && fors->condition != NULL) {
5436                                         warningf(&fors->condition->base.source_position,
5437                                                  "condition of for-statement is unreachable");
5438                                 }
5439
5440                                 if (!fors->step_reachable && fors->step != NULL) {
5441                                         warningf(&fors->step->base.source_position,
5442                                                  "step of for-statement is unreachable");
5443                                 }
5444                         }
5445                         return;
5446                 }
5447
5448                 case STATEMENT_COMPOUND:
5449                         if (stmt->compound.statements != NULL)
5450                                 return;
5451                         goto warn_unreachable;
5452
5453                 case STATEMENT_DECLARATION: {
5454                         /* Only warn if there is at least one declarator with an initializer.
5455                          * This typically occurs in switch statements. */
5456                         declaration_statement_t const *const decl = &stmt->declaration;
5457                         entity_t                const *      ent  = decl->declarations_begin;
5458                         entity_t                const *const last = decl->declarations_end;
5459                         if (ent != NULL) {
5460                                 for (;; ent = ent->base.next) {
5461                                         if (ent->kind                 == ENTITY_VARIABLE &&
5462                                                         ent->variable.initializer != NULL) {
5463                                                 goto warn_unreachable;
5464                                         }
5465                                         if (ent == last)
5466                                                 return;
5467                                 }
5468                         }
5469                 }
5470
5471                 default:
5472 warn_unreachable:
5473                         if (!stmt->base.reachable)
5474                                 warningf(&stmt->base.source_position, "statement is unreachable");
5475                         return;
5476         }
5477 }
5478
5479 static void parse_external_declaration(void)
5480 {
5481         /* function-definitions and declarations both start with declaration
5482          * specifiers */
5483         add_anchor_token(';');
5484         declaration_specifiers_t specifiers;
5485         parse_declaration_specifiers(&specifiers);
5486         rem_anchor_token(';');
5487
5488         /* must be a declaration */
5489         if (token.type == ';') {
5490                 parse_anonymous_declaration_rest(&specifiers);
5491                 return;
5492         }
5493
5494         add_anchor_token(',');
5495         add_anchor_token('=');
5496         add_anchor_token(';');
5497         add_anchor_token('{');
5498
5499         /* declarator is common to both function-definitions and declarations */
5500         entity_t *ndeclaration = parse_declarator(&specifiers, DECL_FLAGS_NONE);
5501
5502         rem_anchor_token('{');
5503         rem_anchor_token(';');
5504         rem_anchor_token('=');
5505         rem_anchor_token(',');
5506
5507         /* must be a declaration */
5508         switch (token.type) {
5509                 case ',':
5510                 case ';':
5511                 case '=':
5512                         parse_declaration_rest(ndeclaration, &specifiers, record_entity,
5513                                         DECL_FLAGS_NONE);
5514                         return;
5515         }
5516
5517         /* must be a function definition */
5518         parse_kr_declaration_list(ndeclaration);
5519
5520         if (token.type != '{') {
5521                 parse_error_expected("while parsing function definition", '{', NULL);
5522                 eat_until_matching_token(';');
5523                 return;
5524         }
5525
5526         assert(is_declaration(ndeclaration));
5527         type_t *const orig_type = ndeclaration->declaration.type;
5528         type_t *      type      = skip_typeref(orig_type);
5529
5530         if (!is_type_function(type)) {
5531                 if (is_type_valid(type)) {
5532                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5533                                type, ndeclaration->base.symbol);
5534                 }
5535                 eat_block();
5536                 return;
5537         } else if (is_typeref(orig_type)) {
5538                 /* §6.9.1:2 */
5539                 errorf(&ndeclaration->base.source_position,
5540                                 "type of function definition '%#T' is a typedef",
5541                                 orig_type, ndeclaration->base.symbol);
5542         }
5543
5544         if (warning.aggregate_return &&
5545             is_type_compound(skip_typeref(type->function.return_type))) {
5546                 warningf(&ndeclaration->base.source_position, "function '%Y' returns an aggregate",
5547                          ndeclaration->base.symbol);
5548         }
5549         if (warning.traditional && !type->function.unspecified_parameters) {
5550                 warningf(&ndeclaration->base.source_position, "traditional C rejects ISO C style function definition of function '%Y'",
5551                         ndeclaration->base.symbol);
5552         }
5553         if (warning.old_style_definition && type->function.unspecified_parameters) {
5554                 warningf(&ndeclaration->base.source_position, "old-style function definition '%Y'",
5555                         ndeclaration->base.symbol);
5556         }
5557
5558         /* §6.7.5.3:14 a function definition with () means no
5559          * parameters (and not unspecified parameters) */
5560         if (type->function.unspecified_parameters &&
5561                         type->function.parameters == NULL) {
5562                 type_t *copy                          = duplicate_type(type);
5563                 copy->function.unspecified_parameters = false;
5564                 type                                  = identify_new_type(copy);
5565
5566                 ndeclaration->declaration.type = type;
5567         }
5568
5569         entity_t *const entity = record_entity(ndeclaration, true);
5570         assert(entity->kind == ENTITY_FUNCTION);
5571         assert(ndeclaration->kind == ENTITY_FUNCTION);
5572
5573         function_t *const function = &entity->function;
5574         if (ndeclaration != entity) {
5575                 function->parameters = ndeclaration->function.parameters;
5576         }
5577         assert(is_declaration(entity));
5578         type = skip_typeref(entity->declaration.type);
5579
5580         /* push function parameters and switch scope */
5581         size_t const  top       = environment_top();
5582         scope_t      *old_scope = scope_push(&function->parameters);
5583
5584         entity_t *parameter = function->parameters.entities;
5585         for (; parameter != NULL; parameter = parameter->base.next) {
5586                 if (parameter->base.parent_scope == &ndeclaration->function.parameters) {
5587                         parameter->base.parent_scope = current_scope;
5588                 }
5589                 assert(parameter->base.parent_scope == NULL
5590                                 || parameter->base.parent_scope == current_scope);
5591                 parameter->base.parent_scope = current_scope;
5592                 if (parameter->base.symbol == NULL) {
5593                         errorf(&parameter->base.source_position, "parameter name omitted");
5594                         continue;
5595                 }
5596                 environment_push(parameter);
5597         }
5598
5599         if (function->statement != NULL) {
5600                 parser_error_multiple_definition(entity, HERE);
5601                 eat_block();
5602         } else {
5603                 /* parse function body */
5604                 int         label_stack_top      = label_top();
5605                 function_t *old_current_function = current_function;
5606                 entity_t   *old_current_entity   = current_entity;
5607                 current_function                 = function;
5608                 current_entity                   = entity;
5609                 current_parent                   = NULL;
5610
5611                 goto_first   = NULL;
5612                 goto_anchor  = &goto_first;
5613                 label_first  = NULL;
5614                 label_anchor = &label_first;
5615
5616                 statement_t *const body = parse_compound_statement(false);
5617                 function->statement = body;
5618                 first_err = true;
5619                 check_labels();
5620                 check_declarations();
5621                 if (warning.return_type      ||
5622                     warning.unreachable_code ||
5623                     (warning.missing_noreturn
5624                      && !(function->base.modifiers & DM_NORETURN))) {
5625                         noreturn_candidate = true;
5626                         check_reachable(body);
5627                         if (warning.unreachable_code)
5628                                 walk_statements(body, check_unreachable, NULL);
5629                         if (warning.missing_noreturn &&
5630                             noreturn_candidate       &&
5631                             !(function->base.modifiers & DM_NORETURN)) {
5632                                 warningf(&body->base.source_position,
5633                                          "function '%#T' is candidate for attribute 'noreturn'",
5634                                          type, entity->base.symbol);
5635                         }
5636                 }
5637
5638                 assert(current_parent   == NULL);
5639                 assert(current_function == function);
5640                 assert(current_entity   == entity);
5641                 current_entity   = old_current_entity;
5642                 current_function = old_current_function;
5643                 label_pop_to(label_stack_top);
5644         }
5645
5646         assert(current_scope == &function->parameters);
5647         scope_pop(old_scope);
5648         environment_pop_to(top);
5649 }
5650
5651 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5652                                   source_position_t *source_position,
5653                                   const symbol_t *symbol)
5654 {
5655         type_t *type = allocate_type_zero(TYPE_BITFIELD);
5656
5657         type->bitfield.base_type       = base_type;
5658         type->bitfield.size_expression = size;
5659
5660         il_size_t bit_size;
5661         type_t *skipped_type = skip_typeref(base_type);
5662         if (!is_type_integer(skipped_type)) {
5663                 errorf(source_position, "bitfield base type '%T' is not an integer type", base_type);
5664                 bit_size = 0;
5665         } else {
5666                 bit_size = get_type_size(base_type) * 8;
5667         }
5668
5669         if (is_constant_expression(size) == EXPR_CLASS_CONSTANT) {
5670                 long v = fold_constant_to_int(size);
5671                 const symbol_t *user_symbol = symbol == NULL ? sym_anonymous : symbol;
5672
5673                 if (v < 0) {
5674                         errorf(source_position, "negative width in bit-field '%Y'",
5675                                user_symbol);
5676                 } else if (v == 0 && symbol != NULL) {
5677                         errorf(source_position, "zero width for bit-field '%Y'",
5678                                user_symbol);
5679                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
5680                         errorf(source_position, "width of '%Y' exceeds its type",
5681                                user_symbol);
5682                 } else {
5683                         type->bitfield.bit_size = v;
5684                 }
5685         }
5686
5687         return type;
5688 }
5689
5690 static entity_t *find_compound_entry(compound_t *compound, symbol_t *symbol)
5691 {
5692         entity_t *iter = compound->members.entities;
5693         for (; iter != NULL; iter = iter->base.next) {
5694                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
5695                         continue;
5696
5697                 if (iter->base.symbol == symbol) {
5698                         return iter;
5699                 } else if (iter->base.symbol == NULL) {
5700                         /* search in anonymous structs and unions */
5701                         type_t *type = skip_typeref(iter->declaration.type);
5702                         if (is_type_compound(type)) {
5703                                 if (find_compound_entry(type->compound.compound, symbol)
5704                                                 != NULL)
5705                                         return iter;
5706                         }
5707                         continue;
5708                 }
5709         }
5710
5711         return NULL;
5712 }
5713
5714 static void check_deprecated(const source_position_t *source_position,
5715                              const entity_t *entity)
5716 {
5717         if (!warning.deprecated_declarations)
5718                 return;
5719         if (!is_declaration(entity))
5720                 return;
5721         if ((entity->declaration.modifiers & DM_DEPRECATED) == 0)
5722                 return;
5723
5724         char const *const prefix = get_entity_kind_name(entity->kind);
5725         const char *deprecated_string
5726                         = get_deprecated_string(entity->declaration.attributes);
5727         if (deprecated_string != NULL) {
5728                 warningf(source_position, "%s '%Y' is deprecated (declared %P): \"%s\"",
5729                                  prefix, entity->base.symbol, &entity->base.source_position,
5730                                  deprecated_string);
5731         } else {
5732                 warningf(source_position, "%s '%Y' is deprecated (declared %P)", prefix,
5733                                  entity->base.symbol, &entity->base.source_position);
5734         }
5735 }
5736
5737
5738 static expression_t *create_select(const source_position_t *pos,
5739                                    expression_t *addr,
5740                                    type_qualifiers_t qualifiers,
5741                                                                    entity_t *entry)
5742 {
5743         assert(entry->kind == ENTITY_COMPOUND_MEMBER);
5744
5745         check_deprecated(pos, entry);
5746
5747         expression_t *select          = allocate_expression_zero(EXPR_SELECT);
5748         select->select.compound       = addr;
5749         select->select.compound_entry = entry;
5750
5751         type_t *entry_type = entry->declaration.type;
5752         type_t *res_type   = get_qualified_type(entry_type, qualifiers);
5753
5754         /* we always do the auto-type conversions; the & and sizeof parser contains
5755          * code to revert this! */
5756         select->base.type = automatic_type_conversion(res_type);
5757         if (res_type->kind == TYPE_BITFIELD) {
5758                 select->base.type = res_type->bitfield.base_type;
5759         }
5760
5761         return select;
5762 }
5763
5764 /**
5765  * Find entry with symbol in compound. Search anonymous structs and unions and
5766  * creates implicit select expressions for them.
5767  * Returns the adress for the innermost compound.
5768  */
5769 static expression_t *find_create_select(const source_position_t *pos,
5770                                         expression_t *addr,
5771                                         type_qualifiers_t qualifiers,
5772                                         compound_t *compound, symbol_t *symbol)
5773 {
5774         entity_t *iter = compound->members.entities;
5775         for (; iter != NULL; iter = iter->base.next) {
5776                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
5777                         continue;
5778
5779                 symbol_t *iter_symbol = iter->base.symbol;
5780                 if (iter_symbol == NULL) {
5781                         type_t *type = iter->declaration.type;
5782                         if (type->kind != TYPE_COMPOUND_STRUCT
5783                                         && type->kind != TYPE_COMPOUND_UNION)
5784                                 continue;
5785
5786                         compound_t *sub_compound = type->compound.compound;
5787
5788                         if (find_compound_entry(sub_compound, symbol) == NULL)
5789                                 continue;
5790
5791                         expression_t *sub_addr = create_select(pos, addr, qualifiers, iter);
5792                         sub_addr->base.source_position = *pos;
5793                         sub_addr->select.implicit      = true;
5794                         return find_create_select(pos, sub_addr, qualifiers, sub_compound,
5795                                                   symbol);
5796                 }
5797
5798                 if (iter_symbol == symbol) {
5799                         return create_select(pos, addr, qualifiers, iter);
5800                 }
5801         }
5802
5803         return NULL;
5804 }
5805
5806 static void parse_compound_declarators(compound_t *compound,
5807                 const declaration_specifiers_t *specifiers)
5808 {
5809         do {
5810                 entity_t *entity;
5811
5812                 if (token.type == ':') {
5813                         source_position_t source_position = *HERE;
5814                         next_token();
5815
5816                         type_t *base_type = specifiers->type;
5817                         expression_t *size = parse_constant_expression();
5818
5819                         type_t *type = make_bitfield_type(base_type, size,
5820                                         &source_position, NULL);
5821
5822                         attribute_t  *attributes = parse_attributes(NULL);
5823                         attribute_t **anchor     = &attributes;
5824                         while (*anchor != NULL)
5825                                 anchor = &(*anchor)->next;
5826                         *anchor = specifiers->attributes;
5827
5828                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER, NAMESPACE_NORMAL, NULL);
5829                         entity->base.source_position               = source_position;
5830                         entity->declaration.declared_storage_class = STORAGE_CLASS_NONE;
5831                         entity->declaration.storage_class          = STORAGE_CLASS_NONE;
5832                         entity->declaration.type                   = type;
5833                         entity->declaration.attributes             = attributes;
5834
5835                         if (attributes != NULL) {
5836                                 handle_entity_attributes(attributes, entity);
5837                         }
5838                         append_entity(&compound->members, entity);
5839                 } else {
5840                         entity = parse_declarator(specifiers,
5841                                         DECL_MAY_BE_ABSTRACT | DECL_CREATE_COMPOUND_MEMBER);
5842                         if (entity->kind == ENTITY_TYPEDEF) {
5843                                 errorf(&entity->base.source_position,
5844                                                 "typedef not allowed as compound member");
5845                         } else {
5846                                 assert(entity->kind == ENTITY_COMPOUND_MEMBER);
5847
5848                                 /* make sure we don't define a symbol multiple times */
5849                                 symbol_t *symbol = entity->base.symbol;
5850                                 if (symbol != NULL) {
5851                                         entity_t *prev = find_compound_entry(compound, symbol);
5852                                         if (prev != NULL) {
5853                                                 errorf(&entity->base.source_position,
5854                                                                 "multiple declarations of symbol '%Y' (declared %P)",
5855                                                                 symbol, &prev->base.source_position);
5856                                         }
5857                                 }
5858
5859                                 if (token.type == ':') {
5860                                         source_position_t source_position = *HERE;
5861                                         next_token();
5862                                         expression_t *size = parse_constant_expression();
5863
5864                                         type_t *type          = entity->declaration.type;
5865                                         type_t *bitfield_type = make_bitfield_type(type, size,
5866                                                         &source_position, entity->base.symbol);
5867
5868                                         attribute_t *attributes = parse_attributes(NULL);
5869                                         entity->declaration.type = bitfield_type;
5870                                         handle_entity_attributes(attributes, entity);
5871                                 } else {
5872                                         type_t *orig_type = entity->declaration.type;
5873                                         type_t *type      = skip_typeref(orig_type);
5874                                         if (is_type_function(type)) {
5875                                                 errorf(&entity->base.source_position,
5876                                                        "compound member '%Y' must not have function type '%T'",
5877                                                                 entity->base.symbol, orig_type);
5878                                         } else if (is_type_incomplete(type)) {
5879                                                 /* §6.7.2.1:16 flexible array member */
5880                                                 if (!is_type_array(type)       ||
5881                                                                 token.type          != ';' ||
5882                                                                 look_ahead(1)->type != '}') {
5883                                                         errorf(&entity->base.source_position,
5884                                                                "compound member '%Y' has incomplete type '%T'",
5885                                                                         entity->base.symbol, orig_type);
5886                                                 }
5887                                         }
5888                                 }
5889
5890                                 append_entity(&compound->members, entity);
5891                         }
5892                 }
5893         } while (next_if(','));
5894         expect(';', end_error);
5895
5896 end_error:
5897         anonymous_entity = NULL;
5898 }
5899
5900 static void parse_compound_type_entries(compound_t *compound)
5901 {
5902         eat('{');
5903         add_anchor_token('}');
5904
5905         while (token.type != '}') {
5906                 if (token.type == T_EOF) {
5907                         errorf(HERE, "EOF while parsing struct");
5908                         break;
5909                 }
5910                 declaration_specifiers_t specifiers;
5911                 parse_declaration_specifiers(&specifiers);
5912                 parse_compound_declarators(compound, &specifiers);
5913         }
5914         rem_anchor_token('}');
5915         next_token();
5916
5917         /* §6.7.2.1:7 */
5918         compound->complete = true;
5919 }
5920
5921 static type_t *parse_typename(void)
5922 {
5923         declaration_specifiers_t specifiers;
5924         parse_declaration_specifiers(&specifiers);
5925         if (specifiers.storage_class != STORAGE_CLASS_NONE
5926                         || specifiers.thread_local) {
5927                 /* TODO: improve error message, user does probably not know what a
5928                  * storage class is...
5929                  */
5930                 errorf(&specifiers.source_position, "typename must not have a storage class");
5931         }
5932
5933         type_t *result = parse_abstract_declarator(specifiers.type);
5934
5935         return result;
5936 }
5937
5938
5939
5940
5941 typedef expression_t* (*parse_expression_function)(void);
5942 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
5943
5944 typedef struct expression_parser_function_t expression_parser_function_t;
5945 struct expression_parser_function_t {
5946         parse_expression_function        parser;
5947         precedence_t                     infix_precedence;
5948         parse_expression_infix_function  infix_parser;
5949 };
5950
5951 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5952
5953 /**
5954  * Prints an error message if an expression was expected but not read
5955  */
5956 static expression_t *expected_expression_error(void)
5957 {
5958         /* skip the error message if the error token was read */
5959         if (token.type != T_ERROR) {
5960                 errorf(HERE, "expected expression, got token %K", &token);
5961         }
5962         next_token();
5963
5964         return create_invalid_expression();
5965 }
5966
5967 static type_t *get_string_type(void)
5968 {
5969         return warning.write_strings ? type_const_char_ptr : type_char_ptr;
5970 }
5971
5972 static type_t *get_wide_string_type(void)
5973 {
5974         return warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
5975 }
5976
5977 /**
5978  * Parse a string constant.
5979  */
5980 static expression_t *parse_string_literal(void)
5981 {
5982         source_position_t begin   = token.source_position;
5983         string_t          res     = token.literal;
5984         bool              is_wide = (token.type == T_WIDE_STRING_LITERAL);
5985
5986         next_token();
5987         while (token.type == T_STRING_LITERAL
5988                         || token.type == T_WIDE_STRING_LITERAL) {
5989                 warn_string_concat(&token.source_position);
5990                 res = concat_strings(&res, &token.literal);
5991                 next_token();
5992                 is_wide |= token.type == T_WIDE_STRING_LITERAL;
5993         }
5994
5995         expression_t *literal;
5996         if (is_wide) {
5997                 literal = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
5998                 literal->base.type = get_wide_string_type();
5999         } else {
6000                 literal = allocate_expression_zero(EXPR_STRING_LITERAL);
6001                 literal->base.type = get_string_type();
6002         }
6003         literal->base.source_position = begin;
6004         literal->literal.value        = res;
6005
6006         return literal;
6007 }
6008
6009 /**
6010  * Parse a boolean constant.
6011  */
6012 static expression_t *parse_boolean_literal(bool value)
6013 {
6014         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_BOOLEAN);
6015         literal->base.source_position = token.source_position;
6016         literal->base.type            = type_bool;
6017         literal->literal.value.begin  = value ? "true" : "false";
6018         literal->literal.value.size   = value ? 4 : 5;
6019
6020         next_token();
6021         return literal;
6022 }
6023
6024 static void warn_traditional_suffix(void)
6025 {
6026         if (!warning.traditional)
6027                 return;
6028         warningf(&token.source_position, "traditional C rejects the '%Y' suffix",
6029                  token.symbol);
6030 }
6031
6032 static void check_integer_suffix(void)
6033 {
6034         symbol_t *suffix = token.symbol;
6035         if (suffix == NULL)
6036                 return;
6037
6038         bool not_traditional = false;
6039         const char *c = suffix->string;
6040         if (*c == 'l' || *c == 'L') {
6041                 ++c;
6042                 if (*c == *(c-1)) {
6043                         not_traditional = true;
6044                         ++c;
6045                         if (*c == 'u' || *c == 'U') {
6046                                 ++c;
6047                         }
6048                 } else if (*c == 'u' || *c == 'U') {
6049                         not_traditional = true;
6050                         ++c;
6051                 }
6052         } else if (*c == 'u' || *c == 'U') {
6053                 not_traditional = true;
6054                 ++c;
6055                 if (*c == 'l' || *c == 'L') {
6056                         ++c;
6057                         if (*c == *(c-1)) {
6058                                 ++c;
6059                         }
6060                 }
6061         }
6062         if (*c != '\0') {
6063                 errorf(&token.source_position,
6064                        "invalid suffix '%s' on integer constant", suffix->string);
6065         } else if (not_traditional) {
6066                 warn_traditional_suffix();
6067         }
6068 }
6069
6070 static type_t *check_floatingpoint_suffix(void)
6071 {
6072         symbol_t *suffix = token.symbol;
6073         type_t   *type   = type_double;
6074         if (suffix == NULL)
6075                 return type;
6076
6077         bool not_traditional = false;
6078         const char *c = suffix->string;
6079         if (*c == 'f' || *c == 'F') {
6080                 ++c;
6081                 type = type_float;
6082         } else if (*c == 'l' || *c == 'L') {
6083                 ++c;
6084                 type = type_long_double;
6085         }
6086         if (*c != '\0') {
6087                 errorf(&token.source_position,
6088                        "invalid suffix '%s' on floatingpoint constant", suffix->string);
6089         } else if (not_traditional) {
6090                 warn_traditional_suffix();
6091         }
6092
6093         return type;
6094 }
6095
6096 /**
6097  * Parse an integer constant.
6098  */
6099 static expression_t *parse_number_literal(void)
6100 {
6101         expression_kind_t  kind;
6102         type_t            *type;
6103
6104         switch (token.type) {
6105         case T_INTEGER:
6106                 kind = EXPR_LITERAL_INTEGER;
6107                 check_integer_suffix();
6108                 type = type_int;
6109                 break;
6110         case T_INTEGER_OCTAL:
6111                 kind = EXPR_LITERAL_INTEGER_OCTAL;
6112                 check_integer_suffix();
6113                 type = type_int;
6114                 break;
6115         case T_INTEGER_HEXADECIMAL:
6116                 kind = EXPR_LITERAL_INTEGER_HEXADECIMAL;
6117                 check_integer_suffix();
6118                 type = type_int;
6119                 break;
6120         case T_FLOATINGPOINT:
6121                 kind = EXPR_LITERAL_FLOATINGPOINT;
6122                 type = check_floatingpoint_suffix();
6123                 break;
6124         case T_FLOATINGPOINT_HEXADECIMAL:
6125                 kind = EXPR_LITERAL_FLOATINGPOINT_HEXADECIMAL;
6126                 type = check_floatingpoint_suffix();
6127                 break;
6128         default:
6129                 panic("unexpected token type in parse_number_literal");
6130         }
6131
6132         expression_t *literal = allocate_expression_zero(kind);
6133         literal->base.source_position = token.source_position;
6134         literal->base.type            = type;
6135         literal->literal.value        = token.literal;
6136         literal->literal.suffix       = token.symbol;
6137         next_token();
6138
6139         /* integer type depends on the size of the number and the size
6140          * representable by the types. The backend/codegeneration has to determine
6141          * that
6142          */
6143         determine_literal_type(&literal->literal);
6144         return literal;
6145 }
6146
6147 /**
6148  * Parse a character constant.
6149  */
6150 static expression_t *parse_character_constant(void)
6151 {
6152         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_CHARACTER);
6153         literal->base.source_position = token.source_position;
6154         literal->base.type            = c_mode & _CXX ? type_char : type_int;
6155         literal->literal.value        = token.literal;
6156
6157         size_t len = literal->literal.value.size;
6158         if (len > 1) {
6159                 if (!GNU_MODE && !(c_mode & _C99)) {
6160                         errorf(HERE, "more than 1 character in character constant");
6161                 } else if (warning.multichar) {
6162                         literal->base.type = type_int;
6163                         warningf(HERE, "multi-character character constant");
6164                 }
6165         }
6166
6167         next_token();
6168         return literal;
6169 }
6170
6171 /**
6172  * Parse a wide character constant.
6173  */
6174 static expression_t *parse_wide_character_constant(void)
6175 {
6176         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_WIDE_CHARACTER);
6177         literal->base.source_position = token.source_position;
6178         literal->base.type            = type_int;
6179         literal->literal.value        = token.literal;
6180
6181         size_t len = wstrlen(&literal->literal.value);
6182         if (len > 1) {
6183                 warningf(HERE, "multi-character character constant");
6184         }
6185
6186         next_token();
6187         return literal;
6188 }
6189
6190 static entity_t *create_implicit_function(symbol_t *symbol,
6191                 const source_position_t *source_position)
6192 {
6193         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6194         ntype->function.return_type            = type_int;
6195         ntype->function.unspecified_parameters = true;
6196         ntype->function.linkage                = LINKAGE_C;
6197         type_t *type                           = identify_new_type(ntype);
6198
6199         entity_t *const entity = allocate_entity_zero(ENTITY_FUNCTION, NAMESPACE_NORMAL, symbol);
6200         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
6201         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
6202         entity->declaration.type                   = type;
6203         entity->declaration.implicit               = true;
6204         entity->base.source_position               = *source_position;
6205
6206         if (current_scope != NULL) {
6207                 bool strict_prototypes_old = warning.strict_prototypes;
6208                 warning.strict_prototypes  = false;
6209                 record_entity(entity, false);
6210                 warning.strict_prototypes = strict_prototypes_old;
6211         }
6212
6213         return entity;
6214 }
6215
6216 /**
6217  * Performs automatic type cast as described in §6.3.2.1.
6218  *
6219  * @param orig_type  the original type
6220  */
6221 static type_t *automatic_type_conversion(type_t *orig_type)
6222 {
6223         type_t *type = skip_typeref(orig_type);
6224         if (is_type_array(type)) {
6225                 array_type_t *array_type   = &type->array;
6226                 type_t       *element_type = array_type->element_type;
6227                 unsigned      qualifiers   = array_type->base.qualifiers;
6228
6229                 return make_pointer_type(element_type, qualifiers);
6230         }
6231
6232         if (is_type_function(type)) {
6233                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6234         }
6235
6236         return orig_type;
6237 }
6238
6239 /**
6240  * reverts the automatic casts of array to pointer types and function
6241  * to function-pointer types as defined §6.3.2.1
6242  */
6243 type_t *revert_automatic_type_conversion(const expression_t *expression)
6244 {
6245         switch (expression->kind) {
6246         case EXPR_REFERENCE: {
6247                 entity_t *entity = expression->reference.entity;
6248                 if (is_declaration(entity)) {
6249                         return entity->declaration.type;
6250                 } else if (entity->kind == ENTITY_ENUM_VALUE) {
6251                         return entity->enum_value.enum_type;
6252                 } else {
6253                         panic("no declaration or enum in reference");
6254                 }
6255         }
6256
6257         case EXPR_SELECT: {
6258                 entity_t *entity = expression->select.compound_entry;
6259                 assert(is_declaration(entity));
6260                 type_t   *type   = entity->declaration.type;
6261                 return get_qualified_type(type,
6262                                 expression->base.type->base.qualifiers);
6263         }
6264
6265         case EXPR_UNARY_DEREFERENCE: {
6266                 const expression_t *const value = expression->unary.value;
6267                 type_t             *const type  = skip_typeref(value->base.type);
6268                 if (!is_type_pointer(type))
6269                         return type_error_type;
6270                 return type->pointer.points_to;
6271         }
6272
6273         case EXPR_ARRAY_ACCESS: {
6274                 const expression_t *array_ref = expression->array_access.array_ref;
6275                 type_t             *type_left = skip_typeref(array_ref->base.type);
6276                 if (!is_type_pointer(type_left))
6277                         return type_error_type;
6278                 return type_left->pointer.points_to;
6279         }
6280
6281         case EXPR_STRING_LITERAL: {
6282                 size_t size = expression->string_literal.value.size;
6283                 return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6284         }
6285
6286         case EXPR_WIDE_STRING_LITERAL: {
6287                 size_t size = wstrlen(&expression->string_literal.value);
6288                 return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6289         }
6290
6291         case EXPR_COMPOUND_LITERAL:
6292                 return expression->compound_literal.type;
6293
6294         default:
6295                 break;
6296         }
6297         return expression->base.type;
6298 }
6299
6300 /**
6301  * Find an entity matching a symbol in a scope.
6302  * Uses current scope if scope is NULL
6303  */
6304 static entity_t *lookup_entity(const scope_t *scope, symbol_t *symbol,
6305                                namespace_tag_t namespc)
6306 {
6307         if (scope == NULL) {
6308                 return get_entity(symbol, namespc);
6309         }
6310
6311         /* we should optimize here, if scope grows above a certain size we should
6312            construct a hashmap here... */
6313         entity_t *entity = scope->entities;
6314         for ( ; entity != NULL; entity = entity->base.next) {
6315                 if (entity->base.symbol == symbol && entity->base.namespc == namespc)
6316                         break;
6317         }
6318
6319         return entity;
6320 }
6321
6322 static entity_t *parse_qualified_identifier(void)
6323 {
6324         /* namespace containing the symbol */
6325         symbol_t          *symbol;
6326         source_position_t  pos;
6327         const scope_t     *lookup_scope = NULL;
6328
6329         if (next_if(T_COLONCOLON))
6330                 lookup_scope = &unit->scope;
6331
6332         entity_t *entity;
6333         while (true) {
6334                 if (token.type != T_IDENTIFIER) {
6335                         parse_error_expected("while parsing identifier", T_IDENTIFIER, NULL);
6336                         return create_error_entity(sym_anonymous, ENTITY_VARIABLE);
6337                 }
6338                 symbol = token.symbol;
6339                 pos    = *HERE;
6340                 next_token();
6341
6342                 /* lookup entity */
6343                 entity = lookup_entity(lookup_scope, symbol, NAMESPACE_NORMAL);
6344
6345                 if (!next_if(T_COLONCOLON))
6346                         break;
6347
6348                 switch (entity->kind) {
6349                 case ENTITY_NAMESPACE:
6350                         lookup_scope = &entity->namespacee.members;
6351                         break;
6352                 case ENTITY_STRUCT:
6353                 case ENTITY_UNION:
6354                 case ENTITY_CLASS:
6355                         lookup_scope = &entity->compound.members;
6356                         break;
6357                 default:
6358                         errorf(&pos, "'%Y' must be a namespace, class, struct or union (but is a %s)",
6359                                symbol, get_entity_kind_name(entity->kind));
6360                         goto end_error;
6361                 }
6362         }
6363
6364         if (entity == NULL) {
6365                 if (!strict_mode && token.type == '(') {
6366                         /* an implicitly declared function */
6367                         if (warning.error_implicit_function_declaration) {
6368                                 errorf(&pos, "implicit declaration of function '%Y'", symbol);
6369                         } else if (warning.implicit_function_declaration) {
6370                                 warningf(&pos, "implicit declaration of function '%Y'", symbol);
6371                         }
6372
6373                         entity = create_implicit_function(symbol, &pos);
6374                 } else {
6375                         errorf(&pos, "unknown identifier '%Y' found.", symbol);
6376                         entity = create_error_entity(symbol, ENTITY_VARIABLE);
6377                 }
6378         }
6379
6380         return entity;
6381
6382 end_error:
6383         /* skip further qualifications */
6384         while (next_if(T_IDENTIFIER) && next_if(T_COLONCOLON)) {}
6385
6386         return create_error_entity(sym_anonymous, ENTITY_VARIABLE);
6387 }
6388
6389 static expression_t *parse_reference(void)
6390 {
6391         source_position_t const pos    = token.source_position;
6392         entity_t         *const entity = parse_qualified_identifier();
6393
6394         type_t *orig_type;
6395         if (is_declaration(entity)) {
6396                 orig_type = entity->declaration.type;
6397         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6398                 orig_type = entity->enum_value.enum_type;
6399         } else {
6400                 panic("expected declaration or enum value in reference");
6401         }
6402
6403         /* we always do the auto-type conversions; the & and sizeof parser contains
6404          * code to revert this! */
6405         type_t *type = automatic_type_conversion(orig_type);
6406
6407         expression_kind_t kind = EXPR_REFERENCE;
6408         if (entity->kind == ENTITY_ENUM_VALUE)
6409                 kind = EXPR_REFERENCE_ENUM_VALUE;
6410
6411         expression_t *expression         = allocate_expression_zero(kind);
6412         expression->base.source_position = pos;
6413         expression->base.type            = type;
6414         expression->reference.entity     = entity;
6415
6416         /* this declaration is used */
6417         if (is_declaration(entity)) {
6418                 entity->declaration.used = true;
6419         }
6420
6421         if (entity->base.parent_scope != file_scope
6422                 && (current_function != NULL
6423                         && entity->base.parent_scope->depth < current_function->parameters.depth)
6424                 && (entity->kind == ENTITY_VARIABLE || entity->kind == ENTITY_PARAMETER)) {
6425                 if (entity->kind == ENTITY_VARIABLE) {
6426                         /* access of a variable from an outer function */
6427                         entity->variable.address_taken = true;
6428                 } else if (entity->kind == ENTITY_PARAMETER) {
6429                         entity->parameter.address_taken = true;
6430                 }
6431                 current_function->need_closure = true;
6432         }
6433
6434         check_deprecated(&pos, entity);
6435
6436         if (warning.init_self && entity == current_init_decl && !in_type_prop
6437             && entity->kind == ENTITY_VARIABLE) {
6438                 current_init_decl = NULL;
6439                 warningf(&pos, "variable '%#T' is initialized by itself",
6440                          entity->declaration.type, entity->base.symbol);
6441         }
6442
6443         return expression;
6444 }
6445
6446 static bool semantic_cast(expression_t *cast)
6447 {
6448         expression_t            *expression      = cast->unary.value;
6449         type_t                  *orig_dest_type  = cast->base.type;
6450         type_t                  *orig_type_right = expression->base.type;
6451         type_t            const *dst_type        = skip_typeref(orig_dest_type);
6452         type_t            const *src_type        = skip_typeref(orig_type_right);
6453         source_position_t const *pos             = &cast->base.source_position;
6454
6455         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
6456         if (dst_type == type_void)
6457                 return true;
6458
6459         /* only integer and pointer can be casted to pointer */
6460         if (is_type_pointer(dst_type)  &&
6461             !is_type_pointer(src_type) &&
6462             !is_type_integer(src_type) &&
6463             is_type_valid(src_type)) {
6464                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
6465                 return false;
6466         }
6467
6468         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
6469                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
6470                 return false;
6471         }
6472
6473         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
6474                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
6475                 return false;
6476         }
6477
6478         if (warning.cast_qual &&
6479             is_type_pointer(src_type) &&
6480             is_type_pointer(dst_type)) {
6481                 type_t *src = skip_typeref(src_type->pointer.points_to);
6482                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
6483                 unsigned missing_qualifiers =
6484                         src->base.qualifiers & ~dst->base.qualifiers;
6485                 if (missing_qualifiers != 0) {
6486                         warningf(pos,
6487                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
6488                                  missing_qualifiers, orig_type_right);
6489                 }
6490         }
6491         return true;
6492 }
6493
6494 static expression_t *parse_compound_literal(type_t *type)
6495 {
6496         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
6497
6498         parse_initializer_env_t env;
6499         env.type             = type;
6500         env.entity           = NULL;
6501         env.must_be_constant = false;
6502         initializer_t *initializer = parse_initializer(&env);
6503         type = env.type;
6504
6505         expression->compound_literal.initializer = initializer;
6506         expression->compound_literal.type        = type;
6507         expression->base.type                    = automatic_type_conversion(type);
6508
6509         return expression;
6510 }
6511
6512 /**
6513  * Parse a cast expression.
6514  */
6515 static expression_t *parse_cast(void)
6516 {
6517         source_position_t source_position = token.source_position;
6518
6519         eat('(');
6520         add_anchor_token(')');
6521
6522         type_t *type = parse_typename();
6523
6524         rem_anchor_token(')');
6525         expect(')', end_error);
6526
6527         if (token.type == '{') {
6528                 return parse_compound_literal(type);
6529         }
6530
6531         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
6532         cast->base.source_position = source_position;
6533
6534         expression_t *value = parse_subexpression(PREC_CAST);
6535         cast->base.type   = type;
6536         cast->unary.value = value;
6537
6538         if (! semantic_cast(cast)) {
6539                 /* TODO: record the error in the AST. else it is impossible to detect it */
6540         }
6541
6542         return cast;
6543 end_error:
6544         return create_invalid_expression();
6545 }
6546
6547 /**
6548  * Parse a statement expression.
6549  */
6550 static expression_t *parse_statement_expression(void)
6551 {
6552         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
6553
6554         eat('(');
6555         add_anchor_token(')');
6556
6557         statement_t *statement          = parse_compound_statement(true);
6558         statement->compound.stmt_expr   = true;
6559         expression->statement.statement = statement;
6560
6561         /* find last statement and use its type */
6562         type_t *type = type_void;
6563         const statement_t *stmt = statement->compound.statements;
6564         if (stmt != NULL) {
6565                 while (stmt->base.next != NULL)
6566                         stmt = stmt->base.next;
6567
6568                 if (stmt->kind == STATEMENT_EXPRESSION) {
6569                         type = stmt->expression.expression->base.type;
6570                 }
6571         } else if (warning.other) {
6572                 warningf(&expression->base.source_position, "empty statement expression ({})");
6573         }
6574         expression->base.type = type;
6575
6576         rem_anchor_token(')');
6577         expect(')', end_error);
6578
6579 end_error:
6580         return expression;
6581 }
6582
6583 /**
6584  * Parse a parenthesized expression.
6585  */
6586 static expression_t *parse_parenthesized_expression(void)
6587 {
6588         token_t const* const la1 = look_ahead(1);
6589         switch (la1->type) {
6590         case '{':
6591                 /* gcc extension: a statement expression */
6592                 return parse_statement_expression();
6593
6594         case T_IDENTIFIER:
6595                 if (is_typedef_symbol(la1->symbol)) {
6596         DECLARATION_START
6597                         return parse_cast();
6598                 }
6599         }
6600
6601         eat('(');
6602         add_anchor_token(')');
6603         expression_t *result = parse_expression();
6604         result->base.parenthesized = true;
6605         rem_anchor_token(')');
6606         expect(')', end_error);
6607
6608 end_error:
6609         return result;
6610 }
6611
6612 static expression_t *parse_function_keyword(void)
6613 {
6614         /* TODO */
6615
6616         if (current_function == NULL) {
6617                 errorf(HERE, "'__func__' used outside of a function");
6618         }
6619
6620         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6621         expression->base.type     = type_char_ptr;
6622         expression->funcname.kind = FUNCNAME_FUNCTION;
6623
6624         next_token();
6625
6626         return expression;
6627 }
6628
6629 static expression_t *parse_pretty_function_keyword(void)
6630 {
6631         if (current_function == NULL) {
6632                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
6633         }
6634
6635         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6636         expression->base.type     = type_char_ptr;
6637         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
6638
6639         eat(T___PRETTY_FUNCTION__);
6640
6641         return expression;
6642 }
6643
6644 static expression_t *parse_funcsig_keyword(void)
6645 {
6646         if (current_function == NULL) {
6647                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
6648         }
6649
6650         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6651         expression->base.type     = type_char_ptr;
6652         expression->funcname.kind = FUNCNAME_FUNCSIG;
6653
6654         eat(T___FUNCSIG__);
6655
6656         return expression;
6657 }
6658
6659 static expression_t *parse_funcdname_keyword(void)
6660 {
6661         if (current_function == NULL) {
6662                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6663         }
6664
6665         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6666         expression->base.type     = type_char_ptr;
6667         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6668
6669         eat(T___FUNCDNAME__);
6670
6671         return expression;
6672 }
6673
6674 static designator_t *parse_designator(void)
6675 {
6676         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6677         result->source_position = *HERE;
6678
6679         if (token.type != T_IDENTIFIER) {
6680                 parse_error_expected("while parsing member designator",
6681                                      T_IDENTIFIER, NULL);
6682                 return NULL;
6683         }
6684         result->symbol = token.symbol;
6685         next_token();
6686
6687         designator_t *last_designator = result;
6688         while (true) {
6689                 if (next_if('.')) {
6690                         if (token.type != T_IDENTIFIER) {
6691                                 parse_error_expected("while parsing member designator",
6692                                                      T_IDENTIFIER, NULL);
6693                                 return NULL;
6694                         }
6695                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6696                         designator->source_position = *HERE;
6697                         designator->symbol          = token.symbol;
6698                         next_token();
6699
6700                         last_designator->next = designator;
6701                         last_designator       = designator;
6702                         continue;
6703                 }
6704                 if (next_if('[')) {
6705                         add_anchor_token(']');
6706                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6707                         designator->source_position = *HERE;
6708                         designator->array_index     = parse_expression();
6709                         rem_anchor_token(']');
6710                         expect(']', end_error);
6711                         if (designator->array_index == NULL) {
6712                                 return NULL;
6713                         }
6714
6715                         last_designator->next = designator;
6716                         last_designator       = designator;
6717                         continue;
6718                 }
6719                 break;
6720         }
6721
6722         return result;
6723 end_error:
6724         return NULL;
6725 }
6726
6727 /**
6728  * Parse the __builtin_offsetof() expression.
6729  */
6730 static expression_t *parse_offsetof(void)
6731 {
6732         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6733         expression->base.type    = type_size_t;
6734
6735         eat(T___builtin_offsetof);
6736
6737         expect('(', end_error);
6738         add_anchor_token(',');
6739         type_t *type = parse_typename();
6740         rem_anchor_token(',');
6741         expect(',', end_error);
6742         add_anchor_token(')');
6743         designator_t *designator = parse_designator();
6744         rem_anchor_token(')');
6745         expect(')', end_error);
6746
6747         expression->offsetofe.type       = type;
6748         expression->offsetofe.designator = designator;
6749
6750         type_path_t path;
6751         memset(&path, 0, sizeof(path));
6752         path.top_type = type;
6753         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6754
6755         descend_into_subtype(&path);
6756
6757         if (!walk_designator(&path, designator, true)) {
6758                 return create_invalid_expression();
6759         }
6760
6761         DEL_ARR_F(path.path);
6762
6763         return expression;
6764 end_error:
6765         return create_invalid_expression();
6766 }
6767
6768 /**
6769  * Parses a _builtin_va_start() expression.
6770  */
6771 static expression_t *parse_va_start(void)
6772 {
6773         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6774
6775         eat(T___builtin_va_start);
6776
6777         expect('(', end_error);
6778         add_anchor_token(',');
6779         expression->va_starte.ap = parse_assignment_expression();
6780         rem_anchor_token(',');
6781         expect(',', end_error);
6782         expression_t *const expr = parse_assignment_expression();
6783         if (expr->kind == EXPR_REFERENCE) {
6784                 entity_t *const entity = expr->reference.entity;
6785                 if (!current_function->base.type->function.variadic) {
6786                         errorf(&expr->base.source_position,
6787                                         "'va_start' used in non-variadic function");
6788                 } else if (entity->base.parent_scope != &current_function->parameters ||
6789                                 entity->base.next != NULL ||
6790                                 entity->kind != ENTITY_PARAMETER) {
6791                         errorf(&expr->base.source_position,
6792                                "second argument of 'va_start' must be last parameter of the current function");
6793                 } else {
6794                         expression->va_starte.parameter = &entity->variable;
6795                 }
6796                 expect(')', end_error);
6797                 return expression;
6798         }
6799         expect(')', end_error);
6800 end_error:
6801         return create_invalid_expression();
6802 }
6803
6804 /**
6805  * Parses a __builtin_va_arg() expression.
6806  */
6807 static expression_t *parse_va_arg(void)
6808 {
6809         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6810
6811         eat(T___builtin_va_arg);
6812
6813         expect('(', end_error);
6814         call_argument_t ap;
6815         ap.expression = parse_assignment_expression();
6816         expression->va_arge.ap = ap.expression;
6817         check_call_argument(type_valist, &ap, 1);
6818
6819         expect(',', end_error);
6820         expression->base.type = parse_typename();
6821         expect(')', end_error);
6822
6823         return expression;
6824 end_error:
6825         return create_invalid_expression();
6826 }
6827
6828 /**
6829  * Parses a __builtin_va_copy() expression.
6830  */
6831 static expression_t *parse_va_copy(void)
6832 {
6833         expression_t *expression = allocate_expression_zero(EXPR_VA_COPY);
6834
6835         eat(T___builtin_va_copy);
6836
6837         expect('(', end_error);
6838         expression_t *dst = parse_assignment_expression();
6839         assign_error_t error = semantic_assign(type_valist, dst);
6840         report_assign_error(error, type_valist, dst, "call argument 1",
6841                             &dst->base.source_position);
6842         expression->va_copye.dst = dst;
6843
6844         expect(',', end_error);
6845
6846         call_argument_t src;
6847         src.expression = parse_assignment_expression();
6848         check_call_argument(type_valist, &src, 2);
6849         expression->va_copye.src = src.expression;
6850         expect(')', end_error);
6851
6852         return expression;
6853 end_error:
6854         return create_invalid_expression();
6855 }
6856
6857 /**
6858  * Parses a __builtin_constant_p() expression.
6859  */
6860 static expression_t *parse_builtin_constant(void)
6861 {
6862         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6863
6864         eat(T___builtin_constant_p);
6865
6866         expect('(', end_error);
6867         add_anchor_token(')');
6868         expression->builtin_constant.value = parse_assignment_expression();
6869         rem_anchor_token(')');
6870         expect(')', end_error);
6871         expression->base.type = type_int;
6872
6873         return expression;
6874 end_error:
6875         return create_invalid_expression();
6876 }
6877
6878 /**
6879  * Parses a __builtin_types_compatible_p() expression.
6880  */
6881 static expression_t *parse_builtin_types_compatible(void)
6882 {
6883         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_TYPES_COMPATIBLE_P);
6884
6885         eat(T___builtin_types_compatible_p);
6886
6887         expect('(', end_error);
6888         add_anchor_token(')');
6889         add_anchor_token(',');
6890         expression->builtin_types_compatible.left = parse_typename();
6891         rem_anchor_token(',');
6892         expect(',', end_error);
6893         expression->builtin_types_compatible.right = parse_typename();
6894         rem_anchor_token(')');
6895         expect(')', end_error);
6896         expression->base.type = type_int;
6897
6898         return expression;
6899 end_error:
6900         return create_invalid_expression();
6901 }
6902
6903 /**
6904  * Parses a __builtin_is_*() compare expression.
6905  */
6906 static expression_t *parse_compare_builtin(void)
6907 {
6908         expression_t *expression;
6909
6910         switch (token.type) {
6911         case T___builtin_isgreater:
6912                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6913                 break;
6914         case T___builtin_isgreaterequal:
6915                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6916                 break;
6917         case T___builtin_isless:
6918                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6919                 break;
6920         case T___builtin_islessequal:
6921                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6922                 break;
6923         case T___builtin_islessgreater:
6924                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6925                 break;
6926         case T___builtin_isunordered:
6927                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6928                 break;
6929         default:
6930                 internal_errorf(HERE, "invalid compare builtin found");
6931         }
6932         expression->base.source_position = *HERE;
6933         next_token();
6934
6935         expect('(', end_error);
6936         expression->binary.left = parse_assignment_expression();
6937         expect(',', end_error);
6938         expression->binary.right = parse_assignment_expression();
6939         expect(')', end_error);
6940
6941         type_t *const orig_type_left  = expression->binary.left->base.type;
6942         type_t *const orig_type_right = expression->binary.right->base.type;
6943
6944         type_t *const type_left  = skip_typeref(orig_type_left);
6945         type_t *const type_right = skip_typeref(orig_type_right);
6946         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6947                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6948                         type_error_incompatible("invalid operands in comparison",
6949                                 &expression->base.source_position, orig_type_left, orig_type_right);
6950                 }
6951         } else {
6952                 semantic_comparison(&expression->binary);
6953         }
6954
6955         return expression;
6956 end_error:
6957         return create_invalid_expression();
6958 }
6959
6960 /**
6961  * Parses a MS assume() expression.
6962  */
6963 static expression_t *parse_assume(void)
6964 {
6965         expression_t *expression = allocate_expression_zero(EXPR_UNARY_ASSUME);
6966
6967         eat(T__assume);
6968
6969         expect('(', end_error);
6970         add_anchor_token(')');
6971         expression->unary.value = parse_assignment_expression();
6972         rem_anchor_token(')');
6973         expect(')', end_error);
6974
6975         expression->base.type = type_void;
6976         return expression;
6977 end_error:
6978         return create_invalid_expression();
6979 }
6980
6981 /**
6982  * Return the label for the current symbol or create a new one.
6983  */
6984 static label_t *get_label(void)
6985 {
6986         assert(token.type == T_IDENTIFIER);
6987         assert(current_function != NULL);
6988
6989         entity_t *label = get_entity(token.symbol, NAMESPACE_LABEL);
6990         /* If we find a local label, we already created the declaration. */
6991         if (label != NULL && label->kind == ENTITY_LOCAL_LABEL) {
6992                 if (label->base.parent_scope != current_scope) {
6993                         assert(label->base.parent_scope->depth < current_scope->depth);
6994                         current_function->goto_to_outer = true;
6995                 }
6996         } else if (label == NULL || label->base.parent_scope != &current_function->parameters) {
6997                 /* There is no matching label in the same function, so create a new one. */
6998                 label = allocate_entity_zero(ENTITY_LABEL, NAMESPACE_LABEL, token.symbol);
6999                 label_push(label);
7000         }
7001
7002         eat(T_IDENTIFIER);
7003         return &label->label;
7004 }
7005
7006 /**
7007  * Parses a GNU && label address expression.
7008  */
7009 static expression_t *parse_label_address(void)
7010 {
7011         source_position_t source_position = token.source_position;
7012         eat(T_ANDAND);
7013         if (token.type != T_IDENTIFIER) {
7014                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7015                 return create_invalid_expression();
7016         }
7017
7018         label_t *const label = get_label();
7019         label->used          = true;
7020         label->address_taken = true;
7021
7022         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7023         expression->base.source_position = source_position;
7024
7025         /* label address is treated as a void pointer */
7026         expression->base.type           = type_void_ptr;
7027         expression->label_address.label = label;
7028         return expression;
7029 }
7030
7031 /**
7032  * Parse a microsoft __noop expression.
7033  */
7034 static expression_t *parse_noop_expression(void)
7035 {
7036         /* the result is a (int)0 */
7037         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_MS_NOOP);
7038         literal->base.type            = type_int;
7039         literal->base.source_position = token.source_position;
7040         literal->literal.value.begin  = "__noop";
7041         literal->literal.value.size   = 6;
7042
7043         eat(T___noop);
7044
7045         if (token.type == '(') {
7046                 /* parse arguments */
7047                 eat('(');
7048                 add_anchor_token(')');
7049                 add_anchor_token(',');
7050
7051                 if (token.type != ')') do {
7052                         (void)parse_assignment_expression();
7053                 } while (next_if(','));
7054         }
7055         rem_anchor_token(',');
7056         rem_anchor_token(')');
7057         expect(')', end_error);
7058
7059 end_error:
7060         return literal;
7061 }
7062
7063 /**
7064  * Parses a primary expression.
7065  */
7066 static expression_t *parse_primary_expression(void)
7067 {
7068         switch (token.type) {
7069         case T_false:                        return parse_boolean_literal(false);
7070         case T_true:                         return parse_boolean_literal(true);
7071         case T_INTEGER:
7072         case T_INTEGER_OCTAL:
7073         case T_INTEGER_HEXADECIMAL:
7074         case T_FLOATINGPOINT:
7075         case T_FLOATINGPOINT_HEXADECIMAL:    return parse_number_literal();
7076         case T_CHARACTER_CONSTANT:           return parse_character_constant();
7077         case T_WIDE_CHARACTER_CONSTANT:      return parse_wide_character_constant();
7078         case T_STRING_LITERAL:
7079         case T_WIDE_STRING_LITERAL:          return parse_string_literal();
7080         case T___FUNCTION__:
7081         case T___func__:                     return parse_function_keyword();
7082         case T___PRETTY_FUNCTION__:          return parse_pretty_function_keyword();
7083         case T___FUNCSIG__:                  return parse_funcsig_keyword();
7084         case T___FUNCDNAME__:                return parse_funcdname_keyword();
7085         case T___builtin_offsetof:           return parse_offsetof();
7086         case T___builtin_va_start:           return parse_va_start();
7087         case T___builtin_va_arg:             return parse_va_arg();
7088         case T___builtin_va_copy:            return parse_va_copy();
7089         case T___builtin_isgreater:
7090         case T___builtin_isgreaterequal:
7091         case T___builtin_isless:
7092         case T___builtin_islessequal:
7093         case T___builtin_islessgreater:
7094         case T___builtin_isunordered:        return parse_compare_builtin();
7095         case T___builtin_constant_p:         return parse_builtin_constant();
7096         case T___builtin_types_compatible_p: return parse_builtin_types_compatible();
7097         case T__assume:                      return parse_assume();
7098         case T_ANDAND:
7099                 if (GNU_MODE)
7100                         return parse_label_address();
7101                 break;
7102
7103         case '(':                            return parse_parenthesized_expression();
7104         case T___noop:                       return parse_noop_expression();
7105
7106         /* Gracefully handle type names while parsing expressions. */
7107         case T_COLONCOLON:
7108                 return parse_reference();
7109         case T_IDENTIFIER:
7110                 if (!is_typedef_symbol(token.symbol)) {
7111                         return parse_reference();
7112                 }
7113                 /* FALLTHROUGH */
7114         DECLARATION_START {
7115                 source_position_t const  pos = *HERE;
7116                 declaration_specifiers_t specifiers;
7117                 parse_declaration_specifiers(&specifiers);
7118                 type_t const *const type = parse_abstract_declarator(specifiers.type);
7119                 errorf(&pos, "encountered type '%T' while parsing expression", type);
7120                 return create_invalid_expression();
7121         }
7122         }
7123
7124         errorf(HERE, "unexpected token %K, expected an expression", &token);
7125         eat_until_anchor();
7126         return create_invalid_expression();
7127 }
7128
7129 static expression_t *parse_array_expression(expression_t *left)
7130 {
7131         expression_t              *const expr = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7132         array_access_expression_t *const arr  = &expr->array_access;
7133
7134         eat('[');
7135         add_anchor_token(']');
7136
7137         expression_t *const inside = parse_expression();
7138
7139         type_t *const orig_type_left   = left->base.type;
7140         type_t *const orig_type_inside = inside->base.type;
7141
7142         type_t *const type_left   = skip_typeref(orig_type_left);
7143         type_t *const type_inside = skip_typeref(orig_type_inside);
7144
7145         expression_t *ref;
7146         expression_t *idx;
7147         type_t       *idx_type;
7148         type_t       *res_type;
7149         if (is_type_pointer(type_left)) {
7150                 ref      = left;
7151                 idx      = inside;
7152                 idx_type = type_inside;
7153                 res_type = type_left->pointer.points_to;
7154                 goto check_idx;
7155         } else if (is_type_pointer(type_inside)) {
7156                 arr->flipped = true;
7157                 ref      = inside;
7158                 idx      = left;
7159                 idx_type = type_left;
7160                 res_type = type_inside->pointer.points_to;
7161 check_idx:
7162                 res_type = automatic_type_conversion(res_type);
7163                 if (!is_type_integer(idx_type)) {
7164                         errorf(&idx->base.source_position, "array subscript must have integer type");
7165                 } else if (is_type_atomic(idx_type, ATOMIC_TYPE_CHAR) && warning.char_subscripts) {
7166                         warningf(&idx->base.source_position, "array subscript has char type");
7167                 }
7168         } else {
7169                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7170                         errorf(&expr->base.source_position, "invalid types '%T[%T]' for array access", orig_type_left, orig_type_inside);
7171                 }
7172                 res_type = type_error_type;
7173                 ref      = left;
7174                 idx      = inside;
7175         }
7176
7177         arr->array_ref = ref;
7178         arr->index     = idx;
7179         arr->base.type = res_type;
7180
7181         rem_anchor_token(']');
7182         expect(']', end_error);
7183 end_error:
7184         return expr;
7185 }
7186
7187 static expression_t *parse_typeprop(expression_kind_t const kind)
7188 {
7189         expression_t  *tp_expression = allocate_expression_zero(kind);
7190         tp_expression->base.type     = type_size_t;
7191
7192         eat(kind == EXPR_SIZEOF ? T_sizeof : T___alignof__);
7193
7194         /* we only refer to a type property, mark this case */
7195         bool old     = in_type_prop;
7196         in_type_prop = true;
7197
7198         type_t       *orig_type;
7199         expression_t *expression;
7200         if (token.type == '(' && is_declaration_specifier(look_ahead(1))) {
7201                 next_token();
7202                 add_anchor_token(')');
7203                 orig_type = parse_typename();
7204                 rem_anchor_token(')');
7205                 expect(')', end_error);
7206
7207                 if (token.type == '{') {
7208                         /* It was not sizeof(type) after all.  It is sizeof of an expression
7209                          * starting with a compound literal */
7210                         expression = parse_compound_literal(orig_type);
7211                         goto typeprop_expression;
7212                 }
7213         } else {
7214                 expression = parse_subexpression(PREC_UNARY);
7215
7216 typeprop_expression:
7217                 tp_expression->typeprop.tp_expression = expression;
7218
7219                 orig_type = revert_automatic_type_conversion(expression);
7220                 expression->base.type = orig_type;
7221         }
7222
7223         tp_expression->typeprop.type   = orig_type;
7224         type_t const* const type       = skip_typeref(orig_type);
7225         char   const*       wrong_type = NULL;
7226         if (is_type_incomplete(type)) {
7227                 if (!is_type_atomic(type, ATOMIC_TYPE_VOID) || !GNU_MODE)
7228                         wrong_type = "incomplete";
7229         } else if (type->kind == TYPE_FUNCTION) {
7230                 if (GNU_MODE) {
7231                         /* function types are allowed (and return 1) */
7232                         if (warning.other) {
7233                                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7234                                 warningf(&tp_expression->base.source_position,
7235                                          "%s expression with function argument returns invalid result", what);
7236                         }
7237                 } else {
7238                         wrong_type = "function";
7239                 }
7240         } else {
7241                 if (is_type_incomplete(type))
7242                         wrong_type = "incomplete";
7243         }
7244         if (type->kind == TYPE_BITFIELD)
7245                 wrong_type = "bitfield";
7246
7247         if (wrong_type != NULL) {
7248                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7249                 errorf(&tp_expression->base.source_position,
7250                                 "operand of %s expression must not be of %s type '%T'",
7251                                 what, wrong_type, orig_type);
7252         }
7253
7254 end_error:
7255         in_type_prop = old;
7256         return tp_expression;
7257 }
7258
7259 static expression_t *parse_sizeof(void)
7260 {
7261         return parse_typeprop(EXPR_SIZEOF);
7262 }
7263
7264 static expression_t *parse_alignof(void)
7265 {
7266         return parse_typeprop(EXPR_ALIGNOF);
7267 }
7268
7269 static expression_t *parse_select_expression(expression_t *addr)
7270 {
7271         assert(token.type == '.' || token.type == T_MINUSGREATER);
7272         bool select_left_arrow = (token.type == T_MINUSGREATER);
7273         source_position_t const pos = *HERE;
7274         next_token();
7275
7276         if (token.type != T_IDENTIFIER) {
7277                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7278                 return create_invalid_expression();
7279         }
7280         symbol_t *symbol = token.symbol;
7281         next_token();
7282
7283         type_t *const orig_type = addr->base.type;
7284         type_t *const type      = skip_typeref(orig_type);
7285
7286         type_t *type_left;
7287         bool    saw_error = false;
7288         if (is_type_pointer(type)) {
7289                 if (!select_left_arrow) {
7290                         errorf(&pos,
7291                                "request for member '%Y' in something not a struct or union, but '%T'",
7292                                symbol, orig_type);
7293                         saw_error = true;
7294                 }
7295                 type_left = skip_typeref(type->pointer.points_to);
7296         } else {
7297                 if (select_left_arrow && is_type_valid(type)) {
7298                         errorf(&pos, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7299                         saw_error = true;
7300                 }
7301                 type_left = type;
7302         }
7303
7304         if (type_left->kind != TYPE_COMPOUND_STRUCT &&
7305             type_left->kind != TYPE_COMPOUND_UNION) {
7306
7307                 if (is_type_valid(type_left) && !saw_error) {
7308                         errorf(&pos,
7309                                "request for member '%Y' in something not a struct or union, but '%T'",
7310                                symbol, type_left);
7311                 }
7312                 return create_invalid_expression();
7313         }
7314
7315         compound_t *compound = type_left->compound.compound;
7316         if (!compound->complete) {
7317                 errorf(&pos, "request for member '%Y' in incomplete type '%T'",
7318                        symbol, type_left);
7319                 return create_invalid_expression();
7320         }
7321
7322         type_qualifiers_t  qualifiers = type_left->base.qualifiers;
7323         expression_t      *result     =
7324                 find_create_select(&pos, addr, qualifiers, compound, symbol);
7325
7326         if (result == NULL) {
7327                 errorf(&pos, "'%T' has no member named '%Y'", orig_type, symbol);
7328                 return create_invalid_expression();
7329         }
7330
7331         return result;
7332 }
7333
7334 static void check_call_argument(type_t          *expected_type,
7335                                 call_argument_t *argument, unsigned pos)
7336 {
7337         type_t         *expected_type_skip = skip_typeref(expected_type);
7338         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7339         expression_t   *arg_expr           = argument->expression;
7340         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7341
7342         /* handle transparent union gnu extension */
7343         if (is_type_union(expected_type_skip)
7344                         && (get_type_modifiers(expected_type) & DM_TRANSPARENT_UNION)) {
7345                 compound_t *union_decl  = expected_type_skip->compound.compound;
7346                 type_t     *best_type   = NULL;
7347                 entity_t   *entry       = union_decl->members.entities;
7348                 for ( ; entry != NULL; entry = entry->base.next) {
7349                         assert(is_declaration(entry));
7350                         type_t *decl_type = entry->declaration.type;
7351                         error = semantic_assign(decl_type, arg_expr);
7352                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7353                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
7354                                 continue;
7355
7356                         if (error == ASSIGN_SUCCESS) {
7357                                 best_type = decl_type;
7358                         } else if (best_type == NULL) {
7359                                 best_type = decl_type;
7360                         }
7361                 }
7362
7363                 if (best_type != NULL) {
7364                         expected_type = best_type;
7365                 }
7366         }
7367
7368         error                = semantic_assign(expected_type, arg_expr);
7369         argument->expression = create_implicit_cast(arg_expr, expected_type);
7370
7371         if (error != ASSIGN_SUCCESS) {
7372                 /* report exact scope in error messages (like "in argument 3") */
7373                 char buf[64];
7374                 snprintf(buf, sizeof(buf), "call argument %u", pos);
7375                 report_assign_error(error, expected_type, arg_expr, buf,
7376                                     &arg_expr->base.source_position);
7377         } else if (warning.traditional || warning.conversion) {
7378                 type_t *const promoted_type = get_default_promoted_type(arg_type);
7379                 if (!types_compatible(expected_type_skip, promoted_type) &&
7380                     !types_compatible(expected_type_skip, type_void_ptr) &&
7381                     !types_compatible(type_void_ptr,      promoted_type)) {
7382                         /* Deliberately show the skipped types in this warning */
7383                         warningf(&arg_expr->base.source_position,
7384                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
7385                                 pos, expected_type_skip, promoted_type);
7386                 }
7387         }
7388 }
7389
7390 /**
7391  * Handle the semantic restrictions of builtin calls
7392  */
7393 static void handle_builtin_argument_restrictions(call_expression_t *call) {
7394         switch (call->function->reference.entity->function.btk) {
7395                 case bk_gnu_builtin_return_address:
7396                 case bk_gnu_builtin_frame_address: {
7397                         /* argument must be constant */
7398                         call_argument_t *argument = call->arguments;
7399
7400                         if (is_constant_expression(argument->expression) == EXPR_CLASS_VARIABLE) {
7401                                 errorf(&call->base.source_position,
7402                                        "argument of '%Y' must be a constant expression",
7403                                        call->function->reference.entity->base.symbol);
7404                         }
7405                         break;
7406                 }
7407                 case bk_gnu_builtin_object_size:
7408                         if (call->arguments == NULL)
7409                                 break;
7410
7411                         call_argument_t *arg = call->arguments->next;
7412                         if (arg != NULL && is_constant_expression(arg->expression) == EXPR_CLASS_VARIABLE) {
7413                                 errorf(&call->base.source_position,
7414                                            "second argument of '%Y' must be a constant expression",
7415                                            call->function->reference.entity->base.symbol);
7416                         }
7417                         break;
7418                 case bk_gnu_builtin_prefetch:
7419                         /* second and third argument must be constant if existent */
7420                         if (call->arguments == NULL)
7421                                 break;
7422                         call_argument_t *rw = call->arguments->next;
7423                         call_argument_t *locality = NULL;
7424
7425                         if (rw != NULL) {
7426                                 if (is_constant_expression(rw->expression) == EXPR_CLASS_VARIABLE) {
7427                                         errorf(&call->base.source_position,
7428                                                "second argument of '%Y' must be a constant expression",
7429                                                call->function->reference.entity->base.symbol);
7430                                 }
7431                                 locality = rw->next;
7432                         }
7433                         if (locality != NULL) {
7434                                 if (is_constant_expression(locality->expression) == EXPR_CLASS_VARIABLE) {
7435                                         errorf(&call->base.source_position,
7436                                                "third argument of '%Y' must be a constant expression",
7437                                                call->function->reference.entity->base.symbol);
7438                                 }
7439                                 locality = rw->next;
7440                         }
7441                         break;
7442                 default:
7443                         break;
7444         }
7445 }
7446
7447 /**
7448  * Parse a call expression, ie. expression '( ... )'.
7449  *
7450  * @param expression  the function address
7451  */
7452 static expression_t *parse_call_expression(expression_t *expression)
7453 {
7454         expression_t      *result = allocate_expression_zero(EXPR_CALL);
7455         call_expression_t *call   = &result->call;
7456         call->function            = expression;
7457
7458         type_t *const orig_type = expression->base.type;
7459         type_t *const type      = skip_typeref(orig_type);
7460
7461         function_type_t *function_type = NULL;
7462         if (is_type_pointer(type)) {
7463                 type_t *const to_type = skip_typeref(type->pointer.points_to);
7464
7465                 if (is_type_function(to_type)) {
7466                         function_type   = &to_type->function;
7467                         call->base.type = function_type->return_type;
7468                 }
7469         }
7470
7471         if (function_type == NULL && is_type_valid(type)) {
7472                 errorf(HERE,
7473                        "called object '%E' (type '%T') is not a pointer to a function",
7474                        expression, orig_type);
7475         }
7476
7477         /* parse arguments */
7478         eat('(');
7479         add_anchor_token(')');
7480         add_anchor_token(',');
7481
7482         if (token.type != ')') {
7483                 call_argument_t **anchor = &call->arguments;
7484                 do {
7485                         call_argument_t *argument = allocate_ast_zero(sizeof(*argument));
7486                         argument->expression = parse_assignment_expression();
7487
7488                         *anchor = argument;
7489                         anchor  = &argument->next;
7490                 } while (next_if(','));
7491         }
7492         rem_anchor_token(',');
7493         rem_anchor_token(')');
7494         expect(')', end_error);
7495
7496         if (function_type == NULL)
7497                 return result;
7498
7499         /* check type and count of call arguments */
7500         function_parameter_t *parameter = function_type->parameters;
7501         call_argument_t      *argument  = call->arguments;
7502         if (!function_type->unspecified_parameters) {
7503                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
7504                                 parameter = parameter->next, argument = argument->next) {
7505                         check_call_argument(parameter->type, argument, ++pos);
7506                 }
7507
7508                 if (parameter != NULL) {
7509                         errorf(&expression->base.source_position, "too few arguments to function '%E'", expression);
7510                 } else if (argument != NULL && !function_type->variadic) {
7511                         errorf(&argument->expression->base.source_position, "too many arguments to function '%E'", expression);
7512                 }
7513         }
7514
7515         /* do default promotion for other arguments */
7516         for (; argument != NULL; argument = argument->next) {
7517                 type_t *type = argument->expression->base.type;
7518                 if (!is_type_object(skip_typeref(type))) {
7519                         errorf(&argument->expression->base.source_position,
7520                                "call argument '%E' must not be void", argument->expression);
7521                 }
7522
7523                 type = get_default_promoted_type(type);
7524
7525                 argument->expression
7526                         = create_implicit_cast(argument->expression, type);
7527         }
7528
7529         check_format(call);
7530
7531         if (warning.aggregate_return &&
7532             is_type_compound(skip_typeref(function_type->return_type))) {
7533                 warningf(&expression->base.source_position,
7534                          "function call has aggregate value");
7535         }
7536
7537         if (expression->kind == EXPR_REFERENCE) {
7538                 reference_expression_t *reference = &expression->reference;
7539                 if (reference->entity->kind == ENTITY_FUNCTION &&
7540                     reference->entity->function.btk != bk_none)
7541                         handle_builtin_argument_restrictions(call);
7542         }
7543
7544 end_error:
7545         return result;
7546 }
7547
7548 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
7549
7550 static bool same_compound_type(const type_t *type1, const type_t *type2)
7551 {
7552         return
7553                 is_type_compound(type1) &&
7554                 type1->kind == type2->kind &&
7555                 type1->compound.compound == type2->compound.compound;
7556 }
7557
7558 static expression_t const *get_reference_address(expression_t const *expr)
7559 {
7560         bool regular_take_address = true;
7561         for (;;) {
7562                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
7563                         expr = expr->unary.value;
7564                 } else {
7565                         regular_take_address = false;
7566                 }
7567
7568                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
7569                         break;
7570
7571                 expr = expr->unary.value;
7572         }
7573
7574         if (expr->kind != EXPR_REFERENCE)
7575                 return NULL;
7576
7577         /* special case for functions which are automatically converted to a
7578          * pointer to function without an extra TAKE_ADDRESS operation */
7579         if (!regular_take_address &&
7580                         expr->reference.entity->kind != ENTITY_FUNCTION) {
7581                 return NULL;
7582         }
7583
7584         return expr;
7585 }
7586
7587 static void warn_reference_address_as_bool(expression_t const* expr)
7588 {
7589         if (!warning.address)
7590                 return;
7591
7592         expr = get_reference_address(expr);
7593         if (expr != NULL) {
7594                 warningf(&expr->base.source_position,
7595                          "the address of '%Y' will always evaluate as 'true'",
7596                          expr->reference.entity->base.symbol);
7597         }
7598 }
7599
7600 static void warn_assignment_in_condition(const expression_t *const expr)
7601 {
7602         if (!warning.parentheses)
7603                 return;
7604         if (expr->base.kind != EXPR_BINARY_ASSIGN)
7605                 return;
7606         if (expr->base.parenthesized)
7607                 return;
7608         warningf(&expr->base.source_position,
7609                         "suggest parentheses around assignment used as truth value");
7610 }
7611
7612 static void semantic_condition(expression_t const *const expr,
7613                                char const *const context)
7614 {
7615         type_t *const type = skip_typeref(expr->base.type);
7616         if (is_type_scalar(type)) {
7617                 warn_reference_address_as_bool(expr);
7618                 warn_assignment_in_condition(expr);
7619         } else if (is_type_valid(type)) {
7620                 errorf(&expr->base.source_position,
7621                                 "%s must have scalar type", context);
7622         }
7623 }
7624
7625 /**
7626  * Parse a conditional expression, ie. 'expression ? ... : ...'.
7627  *
7628  * @param expression  the conditional expression
7629  */
7630 static expression_t *parse_conditional_expression(expression_t *expression)
7631 {
7632         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
7633
7634         conditional_expression_t *conditional = &result->conditional;
7635         conditional->condition                = expression;
7636
7637         eat('?');
7638         add_anchor_token(':');
7639
7640         /* §6.5.15:2  The first operand shall have scalar type. */
7641         semantic_condition(expression, "condition of conditional operator");
7642
7643         expression_t *true_expression = expression;
7644         bool          gnu_cond = false;
7645         if (GNU_MODE && token.type == ':') {
7646                 gnu_cond = true;
7647         } else {
7648                 true_expression = parse_expression();
7649         }
7650         rem_anchor_token(':');
7651         expect(':', end_error);
7652 end_error:;
7653         expression_t *false_expression =
7654                 parse_subexpression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
7655
7656         type_t *const orig_true_type  = true_expression->base.type;
7657         type_t *const orig_false_type = false_expression->base.type;
7658         type_t *const true_type       = skip_typeref(orig_true_type);
7659         type_t *const false_type      = skip_typeref(orig_false_type);
7660
7661         /* 6.5.15.3 */
7662         type_t *result_type;
7663         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
7664                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7665                 /* ISO/IEC 14882:1998(E) §5.16:2 */
7666                 if (true_expression->kind == EXPR_UNARY_THROW) {
7667                         result_type = false_type;
7668                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
7669                         result_type = true_type;
7670                 } else {
7671                         if (warning.other && (
7672                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
7673                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
7674                                         )) {
7675                                 warningf(&conditional->base.source_position,
7676                                                 "ISO C forbids conditional expression with only one void side");
7677                         }
7678                         result_type = type_void;
7679                 }
7680         } else if (is_type_arithmetic(true_type)
7681                    && is_type_arithmetic(false_type)) {
7682                 result_type = semantic_arithmetic(true_type, false_type);
7683         } else if (same_compound_type(true_type, false_type)) {
7684                 /* just take 1 of the 2 types */
7685                 result_type = true_type;
7686         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
7687                 type_t *pointer_type;
7688                 type_t *other_type;
7689                 expression_t *other_expression;
7690                 if (is_type_pointer(true_type) &&
7691                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
7692                         pointer_type     = true_type;
7693                         other_type       = false_type;
7694                         other_expression = false_expression;
7695                 } else {
7696                         pointer_type     = false_type;
7697                         other_type       = true_type;
7698                         other_expression = true_expression;
7699                 }
7700
7701                 if (is_null_pointer_constant(other_expression)) {
7702                         result_type = pointer_type;
7703                 } else if (is_type_pointer(other_type)) {
7704                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
7705                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
7706
7707                         type_t *to;
7708                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
7709                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
7710                                 to = type_void;
7711                         } else if (types_compatible(get_unqualified_type(to1),
7712                                                     get_unqualified_type(to2))) {
7713                                 to = to1;
7714                         } else {
7715                                 if (warning.other) {
7716                                         warningf(&conditional->base.source_position,
7717                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
7718                                                         true_type, false_type);
7719                                 }
7720                                 to = type_void;
7721                         }
7722
7723                         type_t *const type =
7724                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
7725                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
7726                 } else if (is_type_integer(other_type)) {
7727                         if (warning.other) {
7728                                 warningf(&conditional->base.source_position,
7729                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
7730                         }
7731                         result_type = pointer_type;
7732                 } else {
7733                         if (is_type_valid(other_type)) {
7734                                 type_error_incompatible("while parsing conditional",
7735                                                 &expression->base.source_position, true_type, false_type);
7736                         }
7737                         result_type = type_error_type;
7738                 }
7739         } else {
7740                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
7741                         type_error_incompatible("while parsing conditional",
7742                                                 &conditional->base.source_position, true_type,
7743                                                 false_type);
7744                 }
7745                 result_type = type_error_type;
7746         }
7747
7748         conditional->true_expression
7749                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
7750         conditional->false_expression
7751                 = create_implicit_cast(false_expression, result_type);
7752         conditional->base.type = result_type;
7753         return result;
7754 }
7755
7756 /**
7757  * Parse an extension expression.
7758  */
7759 static expression_t *parse_extension(void)
7760 {
7761         eat(T___extension__);
7762
7763         bool old_gcc_extension   = in_gcc_extension;
7764         in_gcc_extension         = true;
7765         expression_t *expression = parse_subexpression(PREC_UNARY);
7766         in_gcc_extension         = old_gcc_extension;
7767         return expression;
7768 }
7769
7770 /**
7771  * Parse a __builtin_classify_type() expression.
7772  */
7773 static expression_t *parse_builtin_classify_type(void)
7774 {
7775         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
7776         result->base.type    = type_int;
7777
7778         eat(T___builtin_classify_type);
7779
7780         expect('(', end_error);
7781         add_anchor_token(')');
7782         expression_t *expression = parse_expression();
7783         rem_anchor_token(')');
7784         expect(')', end_error);
7785         result->classify_type.type_expression = expression;
7786
7787         return result;
7788 end_error:
7789         return create_invalid_expression();
7790 }
7791
7792 /**
7793  * Parse a delete expression
7794  * ISO/IEC 14882:1998(E) §5.3.5
7795  */
7796 static expression_t *parse_delete(void)
7797 {
7798         expression_t *const result = allocate_expression_zero(EXPR_UNARY_DELETE);
7799         result->base.type          = type_void;
7800
7801         eat(T_delete);
7802
7803         if (next_if('[')) {
7804                 result->kind = EXPR_UNARY_DELETE_ARRAY;
7805                 expect(']', end_error);
7806 end_error:;
7807         }
7808
7809         expression_t *const value = parse_subexpression(PREC_CAST);
7810         result->unary.value = value;
7811
7812         type_t *const type = skip_typeref(value->base.type);
7813         if (!is_type_pointer(type)) {
7814                 if (is_type_valid(type)) {
7815                         errorf(&value->base.source_position,
7816                                         "operand of delete must have pointer type");
7817                 }
7818         } else if (warning.other &&
7819                         is_type_atomic(skip_typeref(type->pointer.points_to), ATOMIC_TYPE_VOID)) {
7820                 warningf(&value->base.source_position,
7821                                 "deleting 'void*' is undefined");
7822         }
7823
7824         return result;
7825 }
7826
7827 /**
7828  * Parse a throw expression
7829  * ISO/IEC 14882:1998(E) §15:1
7830  */
7831 static expression_t *parse_throw(void)
7832 {
7833         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
7834         result->base.type          = type_void;
7835
7836         eat(T_throw);
7837
7838         expression_t *value = NULL;
7839         switch (token.type) {
7840                 EXPRESSION_START {
7841                         value = parse_assignment_expression();
7842                         /* ISO/IEC 14882:1998(E) §15.1:3 */
7843                         type_t *const orig_type = value->base.type;
7844                         type_t *const type      = skip_typeref(orig_type);
7845                         if (is_type_incomplete(type)) {
7846                                 errorf(&value->base.source_position,
7847                                                 "cannot throw object of incomplete type '%T'", orig_type);
7848                         } else if (is_type_pointer(type)) {
7849                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
7850                                 if (is_type_incomplete(points_to) &&
7851                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7852                                         errorf(&value->base.source_position,
7853                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
7854                                 }
7855                         }
7856                 }
7857
7858                 default:
7859                         break;
7860         }
7861         result->unary.value = value;
7862
7863         return result;
7864 }
7865
7866 static bool check_pointer_arithmetic(const source_position_t *source_position,
7867                                      type_t *pointer_type,
7868                                      type_t *orig_pointer_type)
7869 {
7870         type_t *points_to = pointer_type->pointer.points_to;
7871         points_to = skip_typeref(points_to);
7872
7873         if (is_type_incomplete(points_to)) {
7874                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7875                         errorf(source_position,
7876                                "arithmetic with pointer to incomplete type '%T' not allowed",
7877                                orig_pointer_type);
7878                         return false;
7879                 } else if (warning.pointer_arith) {
7880                         warningf(source_position,
7881                                  "pointer of type '%T' used in arithmetic",
7882                                  orig_pointer_type);
7883                 }
7884         } else if (is_type_function(points_to)) {
7885                 if (!GNU_MODE) {
7886                         errorf(source_position,
7887                                "arithmetic with pointer to function type '%T' not allowed",
7888                                orig_pointer_type);
7889                         return false;
7890                 } else if (warning.pointer_arith) {
7891                         warningf(source_position,
7892                                  "pointer to a function '%T' used in arithmetic",
7893                                  orig_pointer_type);
7894                 }
7895         }
7896         return true;
7897 }
7898
7899 static bool is_lvalue(const expression_t *expression)
7900 {
7901         /* TODO: doesn't seem to be consistent with §6.3.2.1:1 */
7902         switch (expression->kind) {
7903         case EXPR_ARRAY_ACCESS:
7904         case EXPR_COMPOUND_LITERAL:
7905         case EXPR_REFERENCE:
7906         case EXPR_SELECT:
7907         case EXPR_UNARY_DEREFERENCE:
7908                 return true;
7909
7910         default: {
7911                 type_t *type = skip_typeref(expression->base.type);
7912                 return
7913                         /* ISO/IEC 14882:1998(E) §3.10:3 */
7914                         is_type_reference(type) ||
7915                         /* Claim it is an lvalue, if the type is invalid.  There was a parse
7916                          * error before, which maybe prevented properly recognizing it as
7917                          * lvalue. */
7918                         !is_type_valid(type);
7919         }
7920         }
7921 }
7922
7923 static void semantic_incdec(unary_expression_t *expression)
7924 {
7925         type_t *const orig_type = expression->value->base.type;
7926         type_t *const type      = skip_typeref(orig_type);
7927         if (is_type_pointer(type)) {
7928                 if (!check_pointer_arithmetic(&expression->base.source_position,
7929                                               type, orig_type)) {
7930                         return;
7931                 }
7932         } else if (!is_type_real(type) && is_type_valid(type)) {
7933                 /* TODO: improve error message */
7934                 errorf(&expression->base.source_position,
7935                        "operation needs an arithmetic or pointer type");
7936                 return;
7937         }
7938         if (!is_lvalue(expression->value)) {
7939                 /* TODO: improve error message */
7940                 errorf(&expression->base.source_position, "lvalue required as operand");
7941         }
7942         expression->base.type = orig_type;
7943 }
7944
7945 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
7946 {
7947         type_t *const orig_type = expression->value->base.type;
7948         type_t *const type      = skip_typeref(orig_type);
7949         if (!is_type_arithmetic(type)) {
7950                 if (is_type_valid(type)) {
7951                         /* TODO: improve error message */
7952                         errorf(&expression->base.source_position,
7953                                 "operation needs an arithmetic type");
7954                 }
7955                 return;
7956         }
7957
7958         expression->base.type = orig_type;
7959 }
7960
7961 static void semantic_unexpr_plus(unary_expression_t *expression)
7962 {
7963         semantic_unexpr_arithmetic(expression);
7964         if (warning.traditional)
7965                 warningf(&expression->base.source_position,
7966                         "traditional C rejects the unary plus operator");
7967 }
7968
7969 static void semantic_not(unary_expression_t *expression)
7970 {
7971         /* §6.5.3.3:1  The operand [...] of the ! operator, scalar type. */
7972         semantic_condition(expression->value, "operand of !");
7973         expression->base.type = c_mode & _CXX ? type_bool : type_int;
7974 }
7975
7976 static void semantic_unexpr_integer(unary_expression_t *expression)
7977 {
7978         type_t *const orig_type = expression->value->base.type;
7979         type_t *const type      = skip_typeref(orig_type);
7980         if (!is_type_integer(type)) {
7981                 if (is_type_valid(type)) {
7982                         errorf(&expression->base.source_position,
7983                                "operand of ~ must be of integer type");
7984                 }
7985                 return;
7986         }
7987
7988         expression->base.type = orig_type;
7989 }
7990
7991 static void semantic_dereference(unary_expression_t *expression)
7992 {
7993         type_t *const orig_type = expression->value->base.type;
7994         type_t *const type      = skip_typeref(orig_type);
7995         if (!is_type_pointer(type)) {
7996                 if (is_type_valid(type)) {
7997                         errorf(&expression->base.source_position,
7998                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
7999                 }
8000                 return;
8001         }
8002
8003         type_t *result_type   = type->pointer.points_to;
8004         result_type           = automatic_type_conversion(result_type);
8005         expression->base.type = result_type;
8006 }
8007
8008 /**
8009  * Record that an address is taken (expression represents an lvalue).
8010  *
8011  * @param expression       the expression
8012  * @param may_be_register  if true, the expression might be an register
8013  */
8014 static void set_address_taken(expression_t *expression, bool may_be_register)
8015 {
8016         if (expression->kind != EXPR_REFERENCE)
8017                 return;
8018
8019         entity_t *const entity = expression->reference.entity;
8020
8021         if (entity->kind != ENTITY_VARIABLE && entity->kind != ENTITY_PARAMETER)
8022                 return;
8023
8024         if (entity->declaration.storage_class == STORAGE_CLASS_REGISTER
8025                         && !may_be_register) {
8026                 errorf(&expression->base.source_position,
8027                        "address of register %s '%Y' requested",
8028                        get_entity_kind_name(entity->kind), entity->base.symbol);
8029         }
8030
8031         if (entity->kind == ENTITY_VARIABLE) {
8032                 entity->variable.address_taken = true;
8033         } else {
8034                 assert(entity->kind == ENTITY_PARAMETER);
8035                 entity->parameter.address_taken = true;
8036         }
8037 }
8038
8039 /**
8040  * Check the semantic of the address taken expression.
8041  */
8042 static void semantic_take_addr(unary_expression_t *expression)
8043 {
8044         expression_t *value = expression->value;
8045         value->base.type    = revert_automatic_type_conversion(value);
8046
8047         type_t *orig_type = value->base.type;
8048         type_t *type      = skip_typeref(orig_type);
8049         if (!is_type_valid(type))
8050                 return;
8051
8052         /* §6.5.3.2 */
8053         if (!is_lvalue(value)) {
8054                 errorf(&expression->base.source_position, "'&' requires an lvalue");
8055         }
8056         if (type->kind == TYPE_BITFIELD) {
8057                 errorf(&expression->base.source_position,
8058                        "'&' not allowed on object with bitfield type '%T'",
8059                        type);
8060         }
8061
8062         set_address_taken(value, false);
8063
8064         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8065 }
8066
8067 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8068 static expression_t *parse_##unexpression_type(void)                         \
8069 {                                                                            \
8070         expression_t *unary_expression                                           \
8071                 = allocate_expression_zero(unexpression_type);                       \
8072         eat(token_type);                                                         \
8073         unary_expression->unary.value = parse_subexpression(PREC_UNARY);         \
8074                                                                                  \
8075         sfunc(&unary_expression->unary);                                         \
8076                                                                                  \
8077         return unary_expression;                                                 \
8078 }
8079
8080 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8081                                semantic_unexpr_arithmetic)
8082 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8083                                semantic_unexpr_plus)
8084 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8085                                semantic_not)
8086 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8087                                semantic_dereference)
8088 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8089                                semantic_take_addr)
8090 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8091                                semantic_unexpr_integer)
8092 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8093                                semantic_incdec)
8094 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8095                                semantic_incdec)
8096
8097 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8098                                                sfunc)                         \
8099 static expression_t *parse_##unexpression_type(expression_t *left)            \
8100 {                                                                             \
8101         expression_t *unary_expression                                            \
8102                 = allocate_expression_zero(unexpression_type);                        \
8103         eat(token_type);                                                          \
8104         unary_expression->unary.value = left;                                     \
8105                                                                                   \
8106         sfunc(&unary_expression->unary);                                          \
8107                                                                               \
8108         return unary_expression;                                                  \
8109 }
8110
8111 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8112                                        EXPR_UNARY_POSTFIX_INCREMENT,
8113                                        semantic_incdec)
8114 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8115                                        EXPR_UNARY_POSTFIX_DECREMENT,
8116                                        semantic_incdec)
8117
8118 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8119 {
8120         /* TODO: handle complex + imaginary types */
8121
8122         type_left  = get_unqualified_type(type_left);
8123         type_right = get_unqualified_type(type_right);
8124
8125         /* §6.3.1.8 Usual arithmetic conversions */
8126         if (type_left == type_long_double || type_right == type_long_double) {
8127                 return type_long_double;
8128         } else if (type_left == type_double || type_right == type_double) {
8129                 return type_double;
8130         } else if (type_left == type_float || type_right == type_float) {
8131                 return type_float;
8132         }
8133
8134         type_left  = promote_integer(type_left);
8135         type_right = promote_integer(type_right);
8136
8137         if (type_left == type_right)
8138                 return type_left;
8139
8140         bool const signed_left  = is_type_signed(type_left);
8141         bool const signed_right = is_type_signed(type_right);
8142         int const  rank_left    = get_rank(type_left);
8143         int const  rank_right   = get_rank(type_right);
8144
8145         if (signed_left == signed_right)
8146                 return rank_left >= rank_right ? type_left : type_right;
8147
8148         int     s_rank;
8149         int     u_rank;
8150         type_t *s_type;
8151         type_t *u_type;
8152         if (signed_left) {
8153                 s_rank = rank_left;
8154                 s_type = type_left;
8155                 u_rank = rank_right;
8156                 u_type = type_right;
8157         } else {
8158                 s_rank = rank_right;
8159                 s_type = type_right;
8160                 u_rank = rank_left;
8161                 u_type = type_left;
8162         }
8163
8164         if (u_rank >= s_rank)
8165                 return u_type;
8166
8167         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8168          * easier here... */
8169         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8170                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8171                 return s_type;
8172
8173         switch (s_rank) {
8174                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8175                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8176                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8177
8178                 default: panic("invalid atomic type");
8179         }
8180 }
8181
8182 /**
8183  * Check the semantic restrictions for a binary expression.
8184  */
8185 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8186 {
8187         expression_t *const left            = expression->left;
8188         expression_t *const right           = expression->right;
8189         type_t       *const orig_type_left  = left->base.type;
8190         type_t       *const orig_type_right = right->base.type;
8191         type_t       *const type_left       = skip_typeref(orig_type_left);
8192         type_t       *const type_right      = skip_typeref(orig_type_right);
8193
8194         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8195                 /* TODO: improve error message */
8196                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8197                         errorf(&expression->base.source_position,
8198                                "operation needs arithmetic types");
8199                 }
8200                 return;
8201         }
8202
8203         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8204         expression->left      = create_implicit_cast(left, arithmetic_type);
8205         expression->right     = create_implicit_cast(right, arithmetic_type);
8206         expression->base.type = arithmetic_type;
8207 }
8208
8209 static void semantic_binexpr_integer(binary_expression_t *const expression)
8210 {
8211         expression_t *const left            = expression->left;
8212         expression_t *const right           = expression->right;
8213         type_t       *const orig_type_left  = left->base.type;
8214         type_t       *const orig_type_right = right->base.type;
8215         type_t       *const type_left       = skip_typeref(orig_type_left);
8216         type_t       *const type_right      = skip_typeref(orig_type_right);
8217
8218         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8219                 /* TODO: improve error message */
8220                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8221                         errorf(&expression->base.source_position,
8222                                "operation needs integer types");
8223                 }
8224                 return;
8225         }
8226
8227         type_t *const result_type = semantic_arithmetic(type_left, type_right);
8228         expression->left      = create_implicit_cast(left, result_type);
8229         expression->right     = create_implicit_cast(right, result_type);
8230         expression->base.type = result_type;
8231 }
8232
8233 static void warn_div_by_zero(binary_expression_t const *const expression)
8234 {
8235         if (!warning.div_by_zero ||
8236             !is_type_integer(expression->base.type))
8237                 return;
8238
8239         expression_t const *const right = expression->right;
8240         /* The type of the right operand can be different for /= */
8241         if (is_type_integer(right->base.type)                    &&
8242             is_constant_expression(right) == EXPR_CLASS_CONSTANT &&
8243             !fold_constant_to_bool(right)) {
8244                 warningf(&expression->base.source_position, "division by zero");
8245         }
8246 }
8247
8248 /**
8249  * Check the semantic restrictions for a div/mod expression.
8250  */
8251 static void semantic_divmod_arithmetic(binary_expression_t *expression)
8252 {
8253         semantic_binexpr_arithmetic(expression);
8254         warn_div_by_zero(expression);
8255 }
8256
8257 static void warn_addsub_in_shift(const expression_t *const expr)
8258 {
8259         if (expr->base.parenthesized)
8260                 return;
8261
8262         char op;
8263         switch (expr->kind) {
8264                 case EXPR_BINARY_ADD: op = '+'; break;
8265                 case EXPR_BINARY_SUB: op = '-'; break;
8266                 default:              return;
8267         }
8268
8269         warningf(&expr->base.source_position,
8270                         "suggest parentheses around '%c' inside shift", op);
8271 }
8272
8273 static bool semantic_shift(binary_expression_t *expression)
8274 {
8275         expression_t *const left            = expression->left;
8276         expression_t *const right           = expression->right;
8277         type_t       *const orig_type_left  = left->base.type;
8278         type_t       *const orig_type_right = right->base.type;
8279         type_t       *      type_left       = skip_typeref(orig_type_left);
8280         type_t       *      type_right      = skip_typeref(orig_type_right);
8281
8282         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8283                 /* TODO: improve error message */
8284                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8285                         errorf(&expression->base.source_position,
8286                                "operands of shift operation must have integer types");
8287                 }
8288                 return false;
8289         }
8290
8291         type_left = promote_integer(type_left);
8292
8293         if (is_constant_expression(right) == EXPR_CLASS_CONSTANT) {
8294                 long count = fold_constant_to_int(right);
8295                 if (count < 0) {
8296                         warningf(&right->base.source_position,
8297                                         "shift count must be non-negative");
8298                 } else if ((unsigned long)count >=
8299                                 get_atomic_type_size(type_left->atomic.akind) * 8) {
8300                         warningf(&right->base.source_position,
8301                                         "shift count must be less than type width");
8302                 }
8303         }
8304
8305         type_right        = promote_integer(type_right);
8306         expression->right = create_implicit_cast(right, type_right);
8307
8308         return true;
8309 }
8310
8311 static void semantic_shift_op(binary_expression_t *expression)
8312 {
8313         expression_t *const left  = expression->left;
8314         expression_t *const right = expression->right;
8315
8316         if (!semantic_shift(expression))
8317                 return;
8318
8319         if (warning.parentheses) {
8320                 warn_addsub_in_shift(left);
8321                 warn_addsub_in_shift(right);
8322         }
8323
8324         type_t *const orig_type_left = left->base.type;
8325         type_t *      type_left      = skip_typeref(orig_type_left);
8326
8327         type_left             = promote_integer(type_left);
8328         expression->left      = create_implicit_cast(left, type_left);
8329         expression->base.type = type_left;
8330 }
8331
8332 static void semantic_add(binary_expression_t *expression)
8333 {
8334         expression_t *const left            = expression->left;
8335         expression_t *const right           = expression->right;
8336         type_t       *const orig_type_left  = left->base.type;
8337         type_t       *const orig_type_right = right->base.type;
8338         type_t       *const type_left       = skip_typeref(orig_type_left);
8339         type_t       *const type_right      = skip_typeref(orig_type_right);
8340
8341         /* §6.5.6 */
8342         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8343                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8344                 expression->left  = create_implicit_cast(left, arithmetic_type);
8345                 expression->right = create_implicit_cast(right, arithmetic_type);
8346                 expression->base.type = arithmetic_type;
8347         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8348                 check_pointer_arithmetic(&expression->base.source_position,
8349                                          type_left, orig_type_left);
8350                 expression->base.type = type_left;
8351         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8352                 check_pointer_arithmetic(&expression->base.source_position,
8353                                          type_right, orig_type_right);
8354                 expression->base.type = type_right;
8355         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8356                 errorf(&expression->base.source_position,
8357                        "invalid operands to binary + ('%T', '%T')",
8358                        orig_type_left, orig_type_right);
8359         }
8360 }
8361
8362 static void semantic_sub(binary_expression_t *expression)
8363 {
8364         expression_t            *const left            = expression->left;
8365         expression_t            *const right           = expression->right;
8366         type_t                  *const orig_type_left  = left->base.type;
8367         type_t                  *const orig_type_right = right->base.type;
8368         type_t                  *const type_left       = skip_typeref(orig_type_left);
8369         type_t                  *const type_right      = skip_typeref(orig_type_right);
8370         source_position_t const *const pos             = &expression->base.source_position;
8371
8372         /* §5.6.5 */
8373         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8374                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8375                 expression->left        = create_implicit_cast(left, arithmetic_type);
8376                 expression->right       = create_implicit_cast(right, arithmetic_type);
8377                 expression->base.type =  arithmetic_type;
8378         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8379                 check_pointer_arithmetic(&expression->base.source_position,
8380                                          type_left, orig_type_left);
8381                 expression->base.type = type_left;
8382         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8383                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8384                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8385                 if (!types_compatible(unqual_left, unqual_right)) {
8386                         errorf(pos,
8387                                "subtracting pointers to incompatible types '%T' and '%T'",
8388                                orig_type_left, orig_type_right);
8389                 } else if (!is_type_object(unqual_left)) {
8390                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8391                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8392                                        orig_type_left);
8393                         } else if (warning.other) {
8394                                 warningf(pos, "subtracting pointers to void");
8395                         }
8396                 }
8397                 expression->base.type = type_ptrdiff_t;
8398         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8399                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
8400                        orig_type_left, orig_type_right);
8401         }
8402 }
8403
8404 static void warn_string_literal_address(expression_t const* expr)
8405 {
8406         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8407                 expr = expr->unary.value;
8408                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8409                         return;
8410                 expr = expr->unary.value;
8411         }
8412
8413         if (expr->kind == EXPR_STRING_LITERAL
8414                         || expr->kind == EXPR_WIDE_STRING_LITERAL) {
8415                 warningf(&expr->base.source_position,
8416                         "comparison with string literal results in unspecified behaviour");
8417         }
8418 }
8419
8420 static void warn_comparison_in_comparison(const expression_t *const expr)
8421 {
8422         if (expr->base.parenthesized)
8423                 return;
8424         switch (expr->base.kind) {
8425                 case EXPR_BINARY_LESS:
8426                 case EXPR_BINARY_GREATER:
8427                 case EXPR_BINARY_LESSEQUAL:
8428                 case EXPR_BINARY_GREATEREQUAL:
8429                 case EXPR_BINARY_NOTEQUAL:
8430                 case EXPR_BINARY_EQUAL:
8431                         warningf(&expr->base.source_position,
8432                                         "comparisons like 'x <= y < z' do not have their mathematical meaning");
8433                         break;
8434                 default:
8435                         break;
8436         }
8437 }
8438
8439 static bool maybe_negative(expression_t const *const expr)
8440 {
8441         switch (is_constant_expression(expr)) {
8442                 case EXPR_CLASS_ERROR:    return false;
8443                 case EXPR_CLASS_CONSTANT: return fold_constant_to_int(expr) < 0;
8444                 default:                  return true;
8445         }
8446 }
8447
8448 /**
8449  * Check the semantics of comparison expressions.
8450  *
8451  * @param expression   The expression to check.
8452  */
8453 static void semantic_comparison(binary_expression_t *expression)
8454 {
8455         expression_t *left  = expression->left;
8456         expression_t *right = expression->right;
8457
8458         if (warning.address) {
8459                 warn_string_literal_address(left);
8460                 warn_string_literal_address(right);
8461
8462                 expression_t const* const func_left = get_reference_address(left);
8463                 if (func_left != NULL && is_null_pointer_constant(right)) {
8464                         warningf(&expression->base.source_position,
8465                                  "the address of '%Y' will never be NULL",
8466                                  func_left->reference.entity->base.symbol);
8467                 }
8468
8469                 expression_t const* const func_right = get_reference_address(right);
8470                 if (func_right != NULL && is_null_pointer_constant(right)) {
8471                         warningf(&expression->base.source_position,
8472                                  "the address of '%Y' will never be NULL",
8473                                  func_right->reference.entity->base.symbol);
8474                 }
8475         }
8476
8477         if (warning.parentheses) {
8478                 warn_comparison_in_comparison(left);
8479                 warn_comparison_in_comparison(right);
8480         }
8481
8482         type_t *orig_type_left  = left->base.type;
8483         type_t *orig_type_right = right->base.type;
8484         type_t *type_left       = skip_typeref(orig_type_left);
8485         type_t *type_right      = skip_typeref(orig_type_right);
8486
8487         /* TODO non-arithmetic types */
8488         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8489                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8490
8491                 /* test for signed vs unsigned compares */
8492                 if (warning.sign_compare && is_type_integer(arithmetic_type)) {
8493                         bool const signed_left  = is_type_signed(type_left);
8494                         bool const signed_right = is_type_signed(type_right);
8495                         if (signed_left != signed_right) {
8496                                 /* FIXME long long needs better const folding magic */
8497                                 /* TODO check whether constant value can be represented by other type */
8498                                 if ((signed_left  && maybe_negative(left)) ||
8499                                                 (signed_right && maybe_negative(right))) {
8500                                         warningf(&expression->base.source_position,
8501                                                         "comparison between signed and unsigned");
8502                                 }
8503                         }
8504                 }
8505
8506                 expression->left        = create_implicit_cast(left, arithmetic_type);
8507                 expression->right       = create_implicit_cast(right, arithmetic_type);
8508                 expression->base.type   = arithmetic_type;
8509                 if (warning.float_equal &&
8510                     (expression->base.kind == EXPR_BINARY_EQUAL ||
8511                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
8512                     is_type_float(arithmetic_type)) {
8513                         warningf(&expression->base.source_position,
8514                                  "comparing floating point with == or != is unsafe");
8515                 }
8516         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8517                 /* TODO check compatibility */
8518         } else if (is_type_pointer(type_left)) {
8519                 expression->right = create_implicit_cast(right, type_left);
8520         } else if (is_type_pointer(type_right)) {
8521                 expression->left = create_implicit_cast(left, type_right);
8522         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8523                 type_error_incompatible("invalid operands in comparison",
8524                                         &expression->base.source_position,
8525                                         type_left, type_right);
8526         }
8527         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8528 }
8529
8530 /**
8531  * Checks if a compound type has constant fields.
8532  */
8533 static bool has_const_fields(const compound_type_t *type)
8534 {
8535         compound_t *compound = type->compound;
8536         entity_t   *entry    = compound->members.entities;
8537
8538         for (; entry != NULL; entry = entry->base.next) {
8539                 if (!is_declaration(entry))
8540                         continue;
8541
8542                 const type_t *decl_type = skip_typeref(entry->declaration.type);
8543                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
8544                         return true;
8545         }
8546
8547         return false;
8548 }
8549
8550 static bool is_valid_assignment_lhs(expression_t const* const left)
8551 {
8552         type_t *const orig_type_left = revert_automatic_type_conversion(left);
8553         type_t *const type_left      = skip_typeref(orig_type_left);
8554
8555         if (!is_lvalue(left)) {
8556                 errorf(&left->base.source_position, "left hand side '%E' of assignment is not an lvalue",
8557                        left);
8558                 return false;
8559         }
8560
8561         if (left->kind == EXPR_REFERENCE
8562                         && left->reference.entity->kind == ENTITY_FUNCTION) {
8563                 errorf(&left->base.source_position, "cannot assign to function '%E'", left);
8564                 return false;
8565         }
8566
8567         if (is_type_array(type_left)) {
8568                 errorf(&left->base.source_position, "cannot assign to array '%E'", left);
8569                 return false;
8570         }
8571         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
8572                 errorf(&left->base.source_position, "assignment to read-only location '%E' (type '%T')", left,
8573                        orig_type_left);
8574                 return false;
8575         }
8576         if (is_type_incomplete(type_left)) {
8577                 errorf(&left->base.source_position, "left-hand side '%E' of assignment has incomplete type '%T'",
8578                        left, orig_type_left);
8579                 return false;
8580         }
8581         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
8582                 errorf(&left->base.source_position, "cannot assign to '%E' because compound type '%T' has read-only fields",
8583                        left, orig_type_left);
8584                 return false;
8585         }
8586
8587         return true;
8588 }
8589
8590 static void semantic_arithmetic_assign(binary_expression_t *expression)
8591 {
8592         expression_t *left            = expression->left;
8593         expression_t *right           = expression->right;
8594         type_t       *orig_type_left  = left->base.type;
8595         type_t       *orig_type_right = right->base.type;
8596
8597         if (!is_valid_assignment_lhs(left))
8598                 return;
8599
8600         type_t *type_left  = skip_typeref(orig_type_left);
8601         type_t *type_right = skip_typeref(orig_type_right);
8602
8603         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8604                 /* TODO: improve error message */
8605                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8606                         errorf(&expression->base.source_position,
8607                                "operation needs arithmetic types");
8608                 }
8609                 return;
8610         }
8611
8612         /* combined instructions are tricky. We can't create an implicit cast on
8613          * the left side, because we need the uncasted form for the store.
8614          * The ast2firm pass has to know that left_type must be right_type
8615          * for the arithmetic operation and create a cast by itself */
8616         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8617         expression->right       = create_implicit_cast(right, arithmetic_type);
8618         expression->base.type   = type_left;
8619 }
8620
8621 static void semantic_divmod_assign(binary_expression_t *expression)
8622 {
8623         semantic_arithmetic_assign(expression);
8624         warn_div_by_zero(expression);
8625 }
8626
8627 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
8628 {
8629         expression_t *const left            = expression->left;
8630         expression_t *const right           = expression->right;
8631         type_t       *const orig_type_left  = left->base.type;
8632         type_t       *const orig_type_right = right->base.type;
8633         type_t       *const type_left       = skip_typeref(orig_type_left);
8634         type_t       *const type_right      = skip_typeref(orig_type_right);
8635
8636         if (!is_valid_assignment_lhs(left))
8637                 return;
8638
8639         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8640                 /* combined instructions are tricky. We can't create an implicit cast on
8641                  * the left side, because we need the uncasted form for the store.
8642                  * The ast2firm pass has to know that left_type must be right_type
8643                  * for the arithmetic operation and create a cast by itself */
8644                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
8645                 expression->right     = create_implicit_cast(right, arithmetic_type);
8646                 expression->base.type = type_left;
8647         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8648                 check_pointer_arithmetic(&expression->base.source_position,
8649                                          type_left, orig_type_left);
8650                 expression->base.type = type_left;
8651         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8652                 errorf(&expression->base.source_position,
8653                        "incompatible types '%T' and '%T' in assignment",
8654                        orig_type_left, orig_type_right);
8655         }
8656 }
8657
8658 static void semantic_integer_assign(binary_expression_t *expression)
8659 {
8660         expression_t *left            = expression->left;
8661         expression_t *right           = expression->right;
8662         type_t       *orig_type_left  = left->base.type;
8663         type_t       *orig_type_right = right->base.type;
8664
8665         if (!is_valid_assignment_lhs(left))
8666                 return;
8667
8668         type_t *type_left  = skip_typeref(orig_type_left);
8669         type_t *type_right = skip_typeref(orig_type_right);
8670
8671         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8672                 /* TODO: improve error message */
8673                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8674                         errorf(&expression->base.source_position,
8675                                "operation needs integer types");
8676                 }
8677                 return;
8678         }
8679
8680         /* combined instructions are tricky. We can't create an implicit cast on
8681          * the left side, because we need the uncasted form for the store.
8682          * The ast2firm pass has to know that left_type must be right_type
8683          * for the arithmetic operation and create a cast by itself */
8684         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8685         expression->right       = create_implicit_cast(right, arithmetic_type);
8686         expression->base.type   = type_left;
8687 }
8688
8689 static void semantic_shift_assign(binary_expression_t *expression)
8690 {
8691         expression_t *left           = expression->left;
8692
8693         if (!is_valid_assignment_lhs(left))
8694                 return;
8695
8696         if (!semantic_shift(expression))
8697                 return;
8698
8699         expression->base.type = skip_typeref(left->base.type);
8700 }
8701
8702 static void warn_logical_and_within_or(const expression_t *const expr)
8703 {
8704         if (expr->base.kind != EXPR_BINARY_LOGICAL_AND)
8705                 return;
8706         if (expr->base.parenthesized)
8707                 return;
8708         warningf(&expr->base.source_position,
8709                         "suggest parentheses around && within ||");
8710 }
8711
8712 /**
8713  * Check the semantic restrictions of a logical expression.
8714  */
8715 static void semantic_logical_op(binary_expression_t *expression)
8716 {
8717         /* §6.5.13:2  Each of the operands shall have scalar type.
8718          * §6.5.14:2  Each of the operands shall have scalar type. */
8719         semantic_condition(expression->left,   "left operand of logical operator");
8720         semantic_condition(expression->right, "right operand of logical operator");
8721         if (expression->base.kind == EXPR_BINARY_LOGICAL_OR &&
8722                         warning.parentheses) {
8723                 warn_logical_and_within_or(expression->left);
8724                 warn_logical_and_within_or(expression->right);
8725         }
8726         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8727 }
8728
8729 /**
8730  * Check the semantic restrictions of a binary assign expression.
8731  */
8732 static void semantic_binexpr_assign(binary_expression_t *expression)
8733 {
8734         expression_t *left           = expression->left;
8735         type_t       *orig_type_left = left->base.type;
8736
8737         if (!is_valid_assignment_lhs(left))
8738                 return;
8739
8740         assign_error_t error = semantic_assign(orig_type_left, expression->right);
8741         report_assign_error(error, orig_type_left, expression->right,
8742                         "assignment", &left->base.source_position);
8743         expression->right = create_implicit_cast(expression->right, orig_type_left);
8744         expression->base.type = orig_type_left;
8745 }
8746
8747 /**
8748  * Determine if the outermost operation (or parts thereof) of the given
8749  * expression has no effect in order to generate a warning about this fact.
8750  * Therefore in some cases this only examines some of the operands of the
8751  * expression (see comments in the function and examples below).
8752  * Examples:
8753  *   f() + 23;    // warning, because + has no effect
8754  *   x || f();    // no warning, because x controls execution of f()
8755  *   x ? y : f(); // warning, because y has no effect
8756  *   (void)x;     // no warning to be able to suppress the warning
8757  * This function can NOT be used for an "expression has definitely no effect"-
8758  * analysis. */
8759 static bool expression_has_effect(const expression_t *const expr)
8760 {
8761         switch (expr->kind) {
8762                 case EXPR_UNKNOWN:                    break;
8763                 case EXPR_INVALID:                    return true; /* do NOT warn */
8764                 case EXPR_REFERENCE:                  return false;
8765                 case EXPR_REFERENCE_ENUM_VALUE:       return false;
8766                 case EXPR_LABEL_ADDRESS:              return false;
8767
8768                 /* suppress the warning for microsoft __noop operations */
8769                 case EXPR_LITERAL_MS_NOOP:            return true;
8770                 case EXPR_LITERAL_BOOLEAN:
8771                 case EXPR_LITERAL_CHARACTER:
8772                 case EXPR_LITERAL_WIDE_CHARACTER:
8773                 case EXPR_LITERAL_INTEGER:
8774                 case EXPR_LITERAL_INTEGER_OCTAL:
8775                 case EXPR_LITERAL_INTEGER_HEXADECIMAL:
8776                 case EXPR_LITERAL_FLOATINGPOINT:
8777                 case EXPR_LITERAL_FLOATINGPOINT_HEXADECIMAL: return false;
8778                 case EXPR_STRING_LITERAL:             return false;
8779                 case EXPR_WIDE_STRING_LITERAL:        return false;
8780
8781                 case EXPR_CALL: {
8782                         const call_expression_t *const call = &expr->call;
8783                         if (call->function->kind != EXPR_REFERENCE)
8784                                 return true;
8785
8786                         switch (call->function->reference.entity->function.btk) {
8787                                 /* FIXME: which builtins have no effect? */
8788                                 default:                      return true;
8789                         }
8790                 }
8791
8792                 /* Generate the warning if either the left or right hand side of a
8793                  * conditional expression has no effect */
8794                 case EXPR_CONDITIONAL: {
8795                         conditional_expression_t const *const cond = &expr->conditional;
8796                         expression_t             const *const t    = cond->true_expression;
8797                         return
8798                                 (t == NULL || expression_has_effect(t)) &&
8799                                 expression_has_effect(cond->false_expression);
8800                 }
8801
8802                 case EXPR_SELECT:                     return false;
8803                 case EXPR_ARRAY_ACCESS:               return false;
8804                 case EXPR_SIZEOF:                     return false;
8805                 case EXPR_CLASSIFY_TYPE:              return false;
8806                 case EXPR_ALIGNOF:                    return false;
8807
8808                 case EXPR_FUNCNAME:                   return false;
8809                 case EXPR_BUILTIN_CONSTANT_P:         return false;
8810                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P: return false;
8811                 case EXPR_OFFSETOF:                   return false;
8812                 case EXPR_VA_START:                   return true;
8813                 case EXPR_VA_ARG:                     return true;
8814                 case EXPR_VA_COPY:                    return true;
8815                 case EXPR_STATEMENT:                  return true; // TODO
8816                 case EXPR_COMPOUND_LITERAL:           return false;
8817
8818                 case EXPR_UNARY_NEGATE:               return false;
8819                 case EXPR_UNARY_PLUS:                 return false;
8820                 case EXPR_UNARY_BITWISE_NEGATE:       return false;
8821                 case EXPR_UNARY_NOT:                  return false;
8822                 case EXPR_UNARY_DEREFERENCE:          return false;
8823                 case EXPR_UNARY_TAKE_ADDRESS:         return false;
8824                 case EXPR_UNARY_POSTFIX_INCREMENT:    return true;
8825                 case EXPR_UNARY_POSTFIX_DECREMENT:    return true;
8826                 case EXPR_UNARY_PREFIX_INCREMENT:     return true;
8827                 case EXPR_UNARY_PREFIX_DECREMENT:     return true;
8828
8829                 /* Treat void casts as if they have an effect in order to being able to
8830                  * suppress the warning */
8831                 case EXPR_UNARY_CAST: {
8832                         type_t *const type = skip_typeref(expr->base.type);
8833                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
8834                 }
8835
8836                 case EXPR_UNARY_CAST_IMPLICIT:        return true;
8837                 case EXPR_UNARY_ASSUME:               return true;
8838                 case EXPR_UNARY_DELETE:               return true;
8839                 case EXPR_UNARY_DELETE_ARRAY:         return true;
8840                 case EXPR_UNARY_THROW:                return true;
8841
8842                 case EXPR_BINARY_ADD:                 return false;
8843                 case EXPR_BINARY_SUB:                 return false;
8844                 case EXPR_BINARY_MUL:                 return false;
8845                 case EXPR_BINARY_DIV:                 return false;
8846                 case EXPR_BINARY_MOD:                 return false;
8847                 case EXPR_BINARY_EQUAL:               return false;
8848                 case EXPR_BINARY_NOTEQUAL:            return false;
8849                 case EXPR_BINARY_LESS:                return false;
8850                 case EXPR_BINARY_LESSEQUAL:           return false;
8851                 case EXPR_BINARY_GREATER:             return false;
8852                 case EXPR_BINARY_GREATEREQUAL:        return false;
8853                 case EXPR_BINARY_BITWISE_AND:         return false;
8854                 case EXPR_BINARY_BITWISE_OR:          return false;
8855                 case EXPR_BINARY_BITWISE_XOR:         return false;
8856                 case EXPR_BINARY_SHIFTLEFT:           return false;
8857                 case EXPR_BINARY_SHIFTRIGHT:          return false;
8858                 case EXPR_BINARY_ASSIGN:              return true;
8859                 case EXPR_BINARY_MUL_ASSIGN:          return true;
8860                 case EXPR_BINARY_DIV_ASSIGN:          return true;
8861                 case EXPR_BINARY_MOD_ASSIGN:          return true;
8862                 case EXPR_BINARY_ADD_ASSIGN:          return true;
8863                 case EXPR_BINARY_SUB_ASSIGN:          return true;
8864                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:    return true;
8865                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:   return true;
8866                 case EXPR_BINARY_BITWISE_AND_ASSIGN:  return true;
8867                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:  return true;
8868                 case EXPR_BINARY_BITWISE_OR_ASSIGN:   return true;
8869
8870                 /* Only examine the right hand side of && and ||, because the left hand
8871                  * side already has the effect of controlling the execution of the right
8872                  * hand side */
8873                 case EXPR_BINARY_LOGICAL_AND:
8874                 case EXPR_BINARY_LOGICAL_OR:
8875                 /* Only examine the right hand side of a comma expression, because the left
8876                  * hand side has a separate warning */
8877                 case EXPR_BINARY_COMMA:
8878                         return expression_has_effect(expr->binary.right);
8879
8880                 case EXPR_BINARY_ISGREATER:           return false;
8881                 case EXPR_BINARY_ISGREATEREQUAL:      return false;
8882                 case EXPR_BINARY_ISLESS:              return false;
8883                 case EXPR_BINARY_ISLESSEQUAL:         return false;
8884                 case EXPR_BINARY_ISLESSGREATER:       return false;
8885                 case EXPR_BINARY_ISUNORDERED:         return false;
8886         }
8887
8888         internal_errorf(HERE, "unexpected expression");
8889 }
8890
8891 static void semantic_comma(binary_expression_t *expression)
8892 {
8893         if (warning.unused_value) {
8894                 const expression_t *const left = expression->left;
8895                 if (!expression_has_effect(left)) {
8896                         warningf(&left->base.source_position,
8897                                  "left-hand operand of comma expression has no effect");
8898                 }
8899         }
8900         expression->base.type = expression->right->base.type;
8901 }
8902
8903 /**
8904  * @param prec_r precedence of the right operand
8905  */
8906 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
8907 static expression_t *parse_##binexpression_type(expression_t *left)          \
8908 {                                                                            \
8909         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
8910         binexpr->binary.left  = left;                                            \
8911         eat(token_type);                                                         \
8912                                                                              \
8913         expression_t *right = parse_subexpression(prec_r);                       \
8914                                                                              \
8915         binexpr->binary.right = right;                                           \
8916         sfunc(&binexpr->binary);                                                 \
8917                                                                              \
8918         return binexpr;                                                          \
8919 }
8920
8921 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
8922 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
8923 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
8924 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
8925 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
8926 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
8927 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
8928 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
8929 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
8930 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
8931 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
8932 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
8933 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
8934 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_integer)
8935 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_integer)
8936 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_integer)
8937 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
8938 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
8939 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
8940 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
8941 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
8942 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
8943 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
8944 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
8945 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_shift_assign)
8946 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_shift_assign)
8947 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_integer_assign)
8948 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_integer_assign)
8949 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_integer_assign)
8950 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
8951
8952
8953 static expression_t *parse_subexpression(precedence_t precedence)
8954 {
8955         if (token.type < 0) {
8956                 return expected_expression_error();
8957         }
8958
8959         expression_parser_function_t *parser
8960                 = &expression_parsers[token.type];
8961         source_position_t             source_position = token.source_position;
8962         expression_t                 *left;
8963
8964         if (parser->parser != NULL) {
8965                 left = parser->parser();
8966         } else {
8967                 left = parse_primary_expression();
8968         }
8969         assert(left != NULL);
8970         left->base.source_position = source_position;
8971
8972         while (true) {
8973                 if (token.type < 0) {
8974                         return expected_expression_error();
8975                 }
8976
8977                 parser = &expression_parsers[token.type];
8978                 if (parser->infix_parser == NULL)
8979                         break;
8980                 if (parser->infix_precedence < precedence)
8981                         break;
8982
8983                 left = parser->infix_parser(left);
8984
8985                 assert(left != NULL);
8986                 assert(left->kind != EXPR_UNKNOWN);
8987                 left->base.source_position = source_position;
8988         }
8989
8990         return left;
8991 }
8992
8993 /**
8994  * Parse an expression.
8995  */
8996 static expression_t *parse_expression(void)
8997 {
8998         return parse_subexpression(PREC_EXPRESSION);
8999 }
9000
9001 /**
9002  * Register a parser for a prefix-like operator.
9003  *
9004  * @param parser      the parser function
9005  * @param token_type  the token type of the prefix token
9006  */
9007 static void register_expression_parser(parse_expression_function parser,
9008                                        int token_type)
9009 {
9010         expression_parser_function_t *entry = &expression_parsers[token_type];
9011
9012         if (entry->parser != NULL) {
9013                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9014                 panic("trying to register multiple expression parsers for a token");
9015         }
9016         entry->parser = parser;
9017 }
9018
9019 /**
9020  * Register a parser for an infix operator with given precedence.
9021  *
9022  * @param parser      the parser function
9023  * @param token_type  the token type of the infix operator
9024  * @param precedence  the precedence of the operator
9025  */
9026 static void register_infix_parser(parse_expression_infix_function parser,
9027                                   int token_type, precedence_t precedence)
9028 {
9029         expression_parser_function_t *entry = &expression_parsers[token_type];
9030
9031         if (entry->infix_parser != NULL) {
9032                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9033                 panic("trying to register multiple infix expression parsers for a "
9034                       "token");
9035         }
9036         entry->infix_parser     = parser;
9037         entry->infix_precedence = precedence;
9038 }
9039
9040 /**
9041  * Initialize the expression parsers.
9042  */
9043 static void init_expression_parsers(void)
9044 {
9045         memset(&expression_parsers, 0, sizeof(expression_parsers));
9046
9047         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
9048         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
9049         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
9050         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
9051         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
9052         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
9053         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
9054         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
9055         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
9056         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
9057         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
9058         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
9059         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
9060         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
9061         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
9062         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
9063         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
9064         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
9065         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
9066         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
9067         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
9068         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
9069         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
9070         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
9071         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
9072         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
9073         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
9074         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
9075         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
9076         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
9077         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
9078         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
9079         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
9080         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
9081         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
9082         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
9083         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
9084
9085         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
9086         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
9087         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
9088         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
9089         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
9090         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
9091         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
9092         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
9093         register_expression_parser(parse_sizeof,                      T_sizeof);
9094         register_expression_parser(parse_alignof,                     T___alignof__);
9095         register_expression_parser(parse_extension,                   T___extension__);
9096         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
9097         register_expression_parser(parse_delete,                      T_delete);
9098         register_expression_parser(parse_throw,                       T_throw);
9099 }
9100
9101 /**
9102  * Parse a asm statement arguments specification.
9103  */
9104 static asm_argument_t *parse_asm_arguments(bool is_out)
9105 {
9106         asm_argument_t  *result = NULL;
9107         asm_argument_t **anchor = &result;
9108
9109         while (token.type == T_STRING_LITERAL || token.type == '[') {
9110                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
9111                 memset(argument, 0, sizeof(argument[0]));
9112
9113                 if (next_if('[')) {
9114                         if (token.type != T_IDENTIFIER) {
9115                                 parse_error_expected("while parsing asm argument",
9116                                                      T_IDENTIFIER, NULL);
9117                                 return NULL;
9118                         }
9119                         argument->symbol = token.symbol;
9120
9121                         expect(']', end_error);
9122                 }
9123
9124                 argument->constraints = parse_string_literals();
9125                 expect('(', end_error);
9126                 add_anchor_token(')');
9127                 expression_t *expression = parse_expression();
9128                 rem_anchor_token(')');
9129                 if (is_out) {
9130                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
9131                          * change size or type representation (e.g. int -> long is ok, but
9132                          * int -> float is not) */
9133                         if (expression->kind == EXPR_UNARY_CAST) {
9134                                 type_t      *const type = expression->base.type;
9135                                 type_kind_t  const kind = type->kind;
9136                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
9137                                         unsigned flags;
9138                                         unsigned size;
9139                                         if (kind == TYPE_ATOMIC) {
9140                                                 atomic_type_kind_t const akind = type->atomic.akind;
9141                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9142                                                 size  = get_atomic_type_size(akind);
9143                                         } else {
9144                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9145                                                 size  = get_atomic_type_size(get_intptr_kind());
9146                                         }
9147
9148                                         do {
9149                                                 expression_t *const value      = expression->unary.value;
9150                                                 type_t       *const value_type = value->base.type;
9151                                                 type_kind_t   const value_kind = value_type->kind;
9152
9153                                                 unsigned value_flags;
9154                                                 unsigned value_size;
9155                                                 if (value_kind == TYPE_ATOMIC) {
9156                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
9157                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9158                                                         value_size  = get_atomic_type_size(value_akind);
9159                                                 } else if (value_kind == TYPE_POINTER) {
9160                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9161                                                         value_size  = get_atomic_type_size(get_intptr_kind());
9162                                                 } else {
9163                                                         break;
9164                                                 }
9165
9166                                                 if (value_flags != flags || value_size != size)
9167                                                         break;
9168
9169                                                 expression = value;
9170                                         } while (expression->kind == EXPR_UNARY_CAST);
9171                                 }
9172                         }
9173
9174                         if (!is_lvalue(expression)) {
9175                                 errorf(&expression->base.source_position,
9176                                        "asm output argument is not an lvalue");
9177                         }
9178
9179                         if (argument->constraints.begin[0] == '=')
9180                                 determine_lhs_ent(expression, NULL);
9181                         else
9182                                 mark_vars_read(expression, NULL);
9183                 } else {
9184                         mark_vars_read(expression, NULL);
9185                 }
9186                 argument->expression = expression;
9187                 expect(')', end_error);
9188
9189                 set_address_taken(expression, true);
9190
9191                 *anchor = argument;
9192                 anchor  = &argument->next;
9193
9194                 if (!next_if(','))
9195                         break;
9196         }
9197
9198         return result;
9199 end_error:
9200         return NULL;
9201 }
9202
9203 /**
9204  * Parse a asm statement clobber specification.
9205  */
9206 static asm_clobber_t *parse_asm_clobbers(void)
9207 {
9208         asm_clobber_t *result  = NULL;
9209         asm_clobber_t **anchor = &result;
9210
9211         while (token.type == T_STRING_LITERAL) {
9212                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9213                 clobber->clobber       = parse_string_literals();
9214
9215                 *anchor = clobber;
9216                 anchor  = &clobber->next;
9217
9218                 if (!next_if(','))
9219                         break;
9220         }
9221
9222         return result;
9223 }
9224
9225 /**
9226  * Parse an asm statement.
9227  */
9228 static statement_t *parse_asm_statement(void)
9229 {
9230         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9231         asm_statement_t *asm_statement = &statement->asms;
9232
9233         eat(T_asm);
9234
9235         if (next_if(T_volatile))
9236                 asm_statement->is_volatile = true;
9237
9238         expect('(', end_error);
9239         add_anchor_token(')');
9240         if (token.type != T_STRING_LITERAL) {
9241                 parse_error_expected("after asm(", T_STRING_LITERAL, NULL);
9242                 goto end_of_asm;
9243         }
9244         asm_statement->asm_text = parse_string_literals();
9245
9246         add_anchor_token(':');
9247         if (!next_if(':')) {
9248                 rem_anchor_token(':');
9249                 goto end_of_asm;
9250         }
9251
9252         asm_statement->outputs = parse_asm_arguments(true);
9253         if (!next_if(':')) {
9254                 rem_anchor_token(':');
9255                 goto end_of_asm;
9256         }
9257
9258         asm_statement->inputs = parse_asm_arguments(false);
9259         if (!next_if(':')) {
9260                 rem_anchor_token(':');
9261                 goto end_of_asm;
9262         }
9263         rem_anchor_token(':');
9264
9265         asm_statement->clobbers = parse_asm_clobbers();
9266
9267 end_of_asm:
9268         rem_anchor_token(')');
9269         expect(')', end_error);
9270         expect(';', end_error);
9271
9272         if (asm_statement->outputs == NULL) {
9273                 /* GCC: An 'asm' instruction without any output operands will be treated
9274                  * identically to a volatile 'asm' instruction. */
9275                 asm_statement->is_volatile = true;
9276         }
9277
9278         return statement;
9279 end_error:
9280         return create_invalid_statement();
9281 }
9282
9283 static statement_t *parse_label_inner_statement(statement_t const *const label, char const *const label_kind)
9284 {
9285         statement_t *inner_stmt;
9286         switch (token.type) {
9287                 case '}':
9288                         errorf(&label->base.source_position, "%s at end of compound statement", label_kind);
9289                         inner_stmt = create_invalid_statement();
9290                         break;
9291
9292                 case ';':
9293                         if (label->kind == STATEMENT_LABEL) {
9294                                 /* Eat an empty statement here, to avoid the warning about an empty
9295                                  * statement after a label.  label:; is commonly used to have a label
9296                                  * before a closing brace. */
9297                                 inner_stmt = create_empty_statement();
9298                                 next_token();
9299                                 break;
9300                         }
9301                         /* FALLTHROUGH */
9302
9303                 default:
9304                         inner_stmt = parse_statement();
9305                         /* ISO/IEC 14882:1998(E) §6:1/§6.7  Declarations are statements */
9306                         if (inner_stmt->kind == STATEMENT_DECLARATION && !(c_mode & _CXX)) {
9307                                 errorf(&inner_stmt->base.source_position, "declaration after %s", label_kind);
9308                         }
9309                         break;
9310         }
9311         return inner_stmt;
9312 }
9313
9314 /**
9315  * Parse a case statement.
9316  */
9317 static statement_t *parse_case_statement(void)
9318 {
9319         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9320         source_position_t *const pos       = &statement->base.source_position;
9321
9322         eat(T_case);
9323
9324         expression_t *const expression   = parse_expression();
9325         statement->case_label.expression = expression;
9326         expression_classification_t const expr_class = is_constant_expression(expression);
9327         if (expr_class != EXPR_CLASS_CONSTANT) {
9328                 if (expr_class != EXPR_CLASS_ERROR) {
9329                         errorf(pos, "case label does not reduce to an integer constant");
9330                 }
9331                 statement->case_label.is_bad = true;
9332         } else {
9333                 long const val = fold_constant_to_int(expression);
9334                 statement->case_label.first_case = val;
9335                 statement->case_label.last_case  = val;
9336         }
9337
9338         if (GNU_MODE) {
9339                 if (next_if(T_DOTDOTDOT)) {
9340                         expression_t *const end_range   = parse_expression();
9341                         statement->case_label.end_range = end_range;
9342                         expression_classification_t const end_class = is_constant_expression(end_range);
9343                         if (end_class != EXPR_CLASS_CONSTANT) {
9344                                 if (end_class != EXPR_CLASS_ERROR) {
9345                                         errorf(pos, "case range does not reduce to an integer constant");
9346                                 }
9347                                 statement->case_label.is_bad = true;
9348                         } else {
9349                                 long const val = fold_constant_to_int(end_range);
9350                                 statement->case_label.last_case = val;
9351
9352                                 if (warning.other && val < statement->case_label.first_case) {
9353                                         statement->case_label.is_empty_range = true;
9354                                         warningf(pos, "empty range specified");
9355                                 }
9356                         }
9357                 }
9358         }
9359
9360         PUSH_PARENT(statement);
9361
9362         expect(':', end_error);
9363 end_error:
9364
9365         if (current_switch != NULL) {
9366                 if (! statement->case_label.is_bad) {
9367                         /* Check for duplicate case values */
9368                         case_label_statement_t *c = &statement->case_label;
9369                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9370                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9371                                         continue;
9372
9373                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9374                                         continue;
9375
9376                                 errorf(pos, "duplicate case value (previously used %P)",
9377                                        &l->base.source_position);
9378                                 break;
9379                         }
9380                 }
9381                 /* link all cases into the switch statement */
9382                 if (current_switch->last_case == NULL) {
9383                         current_switch->first_case      = &statement->case_label;
9384                 } else {
9385                         current_switch->last_case->next = &statement->case_label;
9386                 }
9387                 current_switch->last_case = &statement->case_label;
9388         } else {
9389                 errorf(pos, "case label not within a switch statement");
9390         }
9391
9392         statement->case_label.statement = parse_label_inner_statement(statement, "case label");
9393
9394         POP_PARENT;
9395         return statement;
9396 }
9397
9398 /**
9399  * Parse a default statement.
9400  */
9401 static statement_t *parse_default_statement(void)
9402 {
9403         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9404
9405         eat(T_default);
9406
9407         PUSH_PARENT(statement);
9408
9409         expect(':', end_error);
9410 end_error:
9411
9412         if (current_switch != NULL) {
9413                 const case_label_statement_t *def_label = current_switch->default_label;
9414                 if (def_label != NULL) {
9415                         errorf(&statement->base.source_position, "multiple default labels in one switch (previous declared %P)", &def_label->base.source_position);
9416                 } else {
9417                         current_switch->default_label = &statement->case_label;
9418
9419                         /* link all cases into the switch statement */
9420                         if (current_switch->last_case == NULL) {
9421                                 current_switch->first_case      = &statement->case_label;
9422                         } else {
9423                                 current_switch->last_case->next = &statement->case_label;
9424                         }
9425                         current_switch->last_case = &statement->case_label;
9426                 }
9427         } else {
9428                 errorf(&statement->base.source_position,
9429                         "'default' label not within a switch statement");
9430         }
9431
9432         statement->case_label.statement = parse_label_inner_statement(statement, "default label");
9433
9434         POP_PARENT;
9435         return statement;
9436 }
9437
9438 /**
9439  * Parse a label statement.
9440  */
9441 static statement_t *parse_label_statement(void)
9442 {
9443         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9444         label_t     *const label     = get_label();
9445         statement->label.label = label;
9446
9447         PUSH_PARENT(statement);
9448
9449         /* if statement is already set then the label is defined twice,
9450          * otherwise it was just mentioned in a goto/local label declaration so far
9451          */
9452         source_position_t const* const pos = &statement->base.source_position;
9453         if (label->statement != NULL) {
9454                 errorf(pos, "duplicate label '%Y' (declared %P)", label->base.symbol, &label->base.source_position);
9455         } else {
9456                 label->base.source_position = *pos;
9457                 label->statement            = statement;
9458         }
9459
9460         eat(':');
9461
9462         statement->label.statement = parse_label_inner_statement(statement, "label");
9463
9464         /* remember the labels in a list for later checking */
9465         *label_anchor = &statement->label;
9466         label_anchor  = &statement->label.next;
9467
9468         POP_PARENT;
9469         return statement;
9470 }
9471
9472 /**
9473  * Parse an if statement.
9474  */
9475 static statement_t *parse_if(void)
9476 {
9477         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
9478
9479         eat(T_if);
9480
9481         PUSH_PARENT(statement);
9482
9483         add_anchor_token('{');
9484
9485         expect('(', end_error);
9486         add_anchor_token(')');
9487         expression_t *const expr = parse_expression();
9488         statement->ifs.condition = expr;
9489         /* §6.8.4.1:1  The controlling expression of an if statement shall have
9490          *             scalar type. */
9491         semantic_condition(expr, "condition of 'if'-statment");
9492         mark_vars_read(expr, NULL);
9493         rem_anchor_token(')');
9494         expect(')', end_error);
9495
9496 end_error:
9497         rem_anchor_token('{');
9498
9499         add_anchor_token(T_else);
9500         statement_t *const true_stmt = parse_statement();
9501         statement->ifs.true_statement = true_stmt;
9502         rem_anchor_token(T_else);
9503
9504         if (next_if(T_else)) {
9505                 statement->ifs.false_statement = parse_statement();
9506         } else if (warning.parentheses &&
9507                         true_stmt->kind == STATEMENT_IF &&
9508                         true_stmt->ifs.false_statement != NULL) {
9509                 warningf(&true_stmt->base.source_position,
9510                                 "suggest explicit braces to avoid ambiguous 'else'");
9511         }
9512
9513         POP_PARENT;
9514         return statement;
9515 }
9516
9517 /**
9518  * Check that all enums are handled in a switch.
9519  *
9520  * @param statement  the switch statement to check
9521  */
9522 static void check_enum_cases(const switch_statement_t *statement)
9523 {
9524         const type_t *type = skip_typeref(statement->expression->base.type);
9525         if (! is_type_enum(type))
9526                 return;
9527         const enum_type_t *enumt = &type->enumt;
9528
9529         /* if we have a default, no warnings */
9530         if (statement->default_label != NULL)
9531                 return;
9532
9533         /* FIXME: calculation of value should be done while parsing */
9534         /* TODO: quadratic algorithm here. Change to an n log n one */
9535         long            last_value = -1;
9536         const entity_t *entry      = enumt->enume->base.next;
9537         for (; entry != NULL && entry->kind == ENTITY_ENUM_VALUE;
9538              entry = entry->base.next) {
9539                 const expression_t *expression = entry->enum_value.value;
9540                 long                value      = expression != NULL ? fold_constant_to_int(expression) : last_value + 1;
9541                 bool                found      = false;
9542                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
9543                         if (l->expression == NULL)
9544                                 continue;
9545                         if (l->first_case <= value && value <= l->last_case) {
9546                                 found = true;
9547                                 break;
9548                         }
9549                 }
9550                 if (! found) {
9551                         warningf(&statement->base.source_position,
9552                                  "enumeration value '%Y' not handled in switch",
9553                                  entry->base.symbol);
9554                 }
9555                 last_value = value;
9556         }
9557 }
9558
9559 /**
9560  * Parse a switch statement.
9561  */
9562 static statement_t *parse_switch(void)
9563 {
9564         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
9565
9566         eat(T_switch);
9567
9568         PUSH_PARENT(statement);
9569
9570         expect('(', end_error);
9571         add_anchor_token(')');
9572         expression_t *const expr = parse_expression();
9573         mark_vars_read(expr, NULL);
9574         type_t       *      type = skip_typeref(expr->base.type);
9575         if (is_type_integer(type)) {
9576                 type = promote_integer(type);
9577                 if (warning.traditional) {
9578                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
9579                                 warningf(&expr->base.source_position,
9580                                         "'%T' switch expression not converted to '%T' in ISO C",
9581                                         type, type_int);
9582                         }
9583                 }
9584         } else if (is_type_valid(type)) {
9585                 errorf(&expr->base.source_position,
9586                        "switch quantity is not an integer, but '%T'", type);
9587                 type = type_error_type;
9588         }
9589         statement->switchs.expression = create_implicit_cast(expr, type);
9590         expect(')', end_error);
9591         rem_anchor_token(')');
9592
9593         switch_statement_t *rem = current_switch;
9594         current_switch          = &statement->switchs;
9595         statement->switchs.body = parse_statement();
9596         current_switch          = rem;
9597
9598         if (warning.switch_default &&
9599             statement->switchs.default_label == NULL) {
9600                 warningf(&statement->base.source_position, "switch has no default case");
9601         }
9602         if (warning.switch_enum)
9603                 check_enum_cases(&statement->switchs);
9604
9605         POP_PARENT;
9606         return statement;
9607 end_error:
9608         POP_PARENT;
9609         return create_invalid_statement();
9610 }
9611
9612 static statement_t *parse_loop_body(statement_t *const loop)
9613 {
9614         statement_t *const rem = current_loop;
9615         current_loop = loop;
9616
9617         statement_t *const body = parse_statement();
9618
9619         current_loop = rem;
9620         return body;
9621 }
9622
9623 /**
9624  * Parse a while statement.
9625  */
9626 static statement_t *parse_while(void)
9627 {
9628         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
9629
9630         eat(T_while);
9631
9632         PUSH_PARENT(statement);
9633
9634         expect('(', end_error);
9635         add_anchor_token(')');
9636         expression_t *const cond = parse_expression();
9637         statement->whiles.condition = cond;
9638         /* §6.8.5:2    The controlling expression of an iteration statement shall
9639          *             have scalar type. */
9640         semantic_condition(cond, "condition of 'while'-statement");
9641         mark_vars_read(cond, NULL);
9642         rem_anchor_token(')');
9643         expect(')', end_error);
9644
9645         statement->whiles.body = parse_loop_body(statement);
9646
9647         POP_PARENT;
9648         return statement;
9649 end_error:
9650         POP_PARENT;
9651         return create_invalid_statement();
9652 }
9653
9654 /**
9655  * Parse a do statement.
9656  */
9657 static statement_t *parse_do(void)
9658 {
9659         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
9660
9661         eat(T_do);
9662
9663         PUSH_PARENT(statement);
9664
9665         add_anchor_token(T_while);
9666         statement->do_while.body = parse_loop_body(statement);
9667         rem_anchor_token(T_while);
9668
9669         expect(T_while, end_error);
9670         expect('(', end_error);
9671         add_anchor_token(')');
9672         expression_t *const cond = parse_expression();
9673         statement->do_while.condition = cond;
9674         /* §6.8.5:2    The controlling expression of an iteration statement shall
9675          *             have scalar type. */
9676         semantic_condition(cond, "condition of 'do-while'-statement");
9677         mark_vars_read(cond, NULL);
9678         rem_anchor_token(')');
9679         expect(')', end_error);
9680         expect(';', end_error);
9681
9682         POP_PARENT;
9683         return statement;
9684 end_error:
9685         POP_PARENT;
9686         return create_invalid_statement();
9687 }
9688
9689 /**
9690  * Parse a for statement.
9691  */
9692 static statement_t *parse_for(void)
9693 {
9694         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
9695
9696         eat(T_for);
9697
9698         expect('(', end_error1);
9699         add_anchor_token(')');
9700
9701         PUSH_PARENT(statement);
9702
9703         size_t const  top       = environment_top();
9704         scope_t      *old_scope = scope_push(&statement->fors.scope);
9705
9706         bool old_gcc_extension = in_gcc_extension;
9707         while (next_if(T___extension__)) {
9708                 in_gcc_extension = true;
9709         }
9710
9711         if (next_if(';')) {
9712         } else if (is_declaration_specifier(&token)) {
9713                 parse_declaration(record_entity, DECL_FLAGS_NONE);
9714         } else {
9715                 add_anchor_token(';');
9716                 expression_t *const init = parse_expression();
9717                 statement->fors.initialisation = init;
9718                 mark_vars_read(init, ENT_ANY);
9719                 if (warning.unused_value && !expression_has_effect(init)) {
9720                         warningf(&init->base.source_position,
9721                                         "initialisation of 'for'-statement has no effect");
9722                 }
9723                 rem_anchor_token(';');
9724                 expect(';', end_error2);
9725         }
9726         in_gcc_extension = old_gcc_extension;
9727
9728         if (token.type != ';') {
9729                 add_anchor_token(';');
9730                 expression_t *const cond = parse_expression();
9731                 statement->fors.condition = cond;
9732                 /* §6.8.5:2    The controlling expression of an iteration statement
9733                  *             shall have scalar type. */
9734                 semantic_condition(cond, "condition of 'for'-statement");
9735                 mark_vars_read(cond, NULL);
9736                 rem_anchor_token(';');
9737         }
9738         expect(';', end_error2);
9739         if (token.type != ')') {
9740                 expression_t *const step = parse_expression();
9741                 statement->fors.step = step;
9742                 mark_vars_read(step, ENT_ANY);
9743                 if (warning.unused_value && !expression_has_effect(step)) {
9744                         warningf(&step->base.source_position,
9745                                  "step of 'for'-statement has no effect");
9746                 }
9747         }
9748         expect(')', end_error2);
9749         rem_anchor_token(')');
9750         statement->fors.body = parse_loop_body(statement);
9751
9752         assert(current_scope == &statement->fors.scope);
9753         scope_pop(old_scope);
9754         environment_pop_to(top);
9755
9756         POP_PARENT;
9757         return statement;
9758
9759 end_error2:
9760         POP_PARENT;
9761         rem_anchor_token(')');
9762         assert(current_scope == &statement->fors.scope);
9763         scope_pop(old_scope);
9764         environment_pop_to(top);
9765         /* fallthrough */
9766
9767 end_error1:
9768         return create_invalid_statement();
9769 }
9770
9771 /**
9772  * Parse a goto statement.
9773  */
9774 static statement_t *parse_goto(void)
9775 {
9776         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
9777         eat(T_goto);
9778
9779         if (GNU_MODE && next_if('*')) {
9780                 expression_t *expression = parse_expression();
9781                 mark_vars_read(expression, NULL);
9782
9783                 /* Argh: although documentation says the expression must be of type void*,
9784                  * gcc accepts anything that can be casted into void* without error */
9785                 type_t *type = expression->base.type;
9786
9787                 if (type != type_error_type) {
9788                         if (!is_type_pointer(type) && !is_type_integer(type)) {
9789                                 errorf(&expression->base.source_position,
9790                                         "cannot convert to a pointer type");
9791                         } else if (warning.other && type != type_void_ptr) {
9792                                 warningf(&expression->base.source_position,
9793                                         "type of computed goto expression should be 'void*' not '%T'", type);
9794                         }
9795                         expression = create_implicit_cast(expression, type_void_ptr);
9796                 }
9797
9798                 statement->gotos.expression = expression;
9799         } else if (token.type == T_IDENTIFIER) {
9800                 label_t *const label = get_label();
9801                 label->used            = true;
9802                 statement->gotos.label = label;
9803         } else {
9804                 if (GNU_MODE)
9805                         parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
9806                 else
9807                         parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
9808                 eat_until_anchor();
9809                 return create_invalid_statement();
9810         }
9811
9812         /* remember the goto's in a list for later checking */
9813         *goto_anchor = &statement->gotos;
9814         goto_anchor  = &statement->gotos.next;
9815
9816         expect(';', end_error);
9817
9818 end_error:
9819         return statement;
9820 }
9821
9822 /**
9823  * Parse a continue statement.
9824  */
9825 static statement_t *parse_continue(void)
9826 {
9827         if (current_loop == NULL) {
9828                 errorf(HERE, "continue statement not within loop");
9829         }
9830
9831         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
9832
9833         eat(T_continue);
9834         expect(';', end_error);
9835
9836 end_error:
9837         return statement;
9838 }
9839
9840 /**
9841  * Parse a break statement.
9842  */
9843 static statement_t *parse_break(void)
9844 {
9845         if (current_switch == NULL && current_loop == NULL) {
9846                 errorf(HERE, "break statement not within loop or switch");
9847         }
9848
9849         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
9850
9851         eat(T_break);
9852         expect(';', end_error);
9853
9854 end_error:
9855         return statement;
9856 }
9857
9858 /**
9859  * Parse a __leave statement.
9860  */
9861 static statement_t *parse_leave_statement(void)
9862 {
9863         if (current_try == NULL) {
9864                 errorf(HERE, "__leave statement not within __try");
9865         }
9866
9867         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
9868
9869         eat(T___leave);
9870         expect(';', end_error);
9871
9872 end_error:
9873         return statement;
9874 }
9875
9876 /**
9877  * Check if a given entity represents a local variable.
9878  */
9879 static bool is_local_variable(const entity_t *entity)
9880 {
9881         if (entity->kind != ENTITY_VARIABLE)
9882                 return false;
9883
9884         switch ((storage_class_tag_t) entity->declaration.storage_class) {
9885         case STORAGE_CLASS_AUTO:
9886         case STORAGE_CLASS_REGISTER: {
9887                 const type_t *type = skip_typeref(entity->declaration.type);
9888                 if (is_type_function(type)) {
9889                         return false;
9890                 } else {
9891                         return true;
9892                 }
9893         }
9894         default:
9895                 return false;
9896         }
9897 }
9898
9899 /**
9900  * Check if a given expression represents a local variable.
9901  */
9902 static bool expression_is_local_variable(const expression_t *expression)
9903 {
9904         if (expression->base.kind != EXPR_REFERENCE) {
9905                 return false;
9906         }
9907         const entity_t *entity = expression->reference.entity;
9908         return is_local_variable(entity);
9909 }
9910
9911 /**
9912  * Check if a given expression represents a local variable and
9913  * return its declaration then, else return NULL.
9914  */
9915 entity_t *expression_is_variable(const expression_t *expression)
9916 {
9917         if (expression->base.kind != EXPR_REFERENCE) {
9918                 return NULL;
9919         }
9920         entity_t *entity = expression->reference.entity;
9921         if (entity->kind != ENTITY_VARIABLE)
9922                 return NULL;
9923
9924         return entity;
9925 }
9926
9927 /**
9928  * Parse a return statement.
9929  */
9930 static statement_t *parse_return(void)
9931 {
9932         eat(T_return);
9933
9934         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
9935
9936         expression_t *return_value = NULL;
9937         if (token.type != ';') {
9938                 return_value = parse_expression();
9939                 mark_vars_read(return_value, NULL);
9940         }
9941
9942         const type_t *const func_type = skip_typeref(current_function->base.type);
9943         assert(is_type_function(func_type));
9944         type_t *const return_type = skip_typeref(func_type->function.return_type);
9945
9946         source_position_t const *const pos = &statement->base.source_position;
9947         if (return_value != NULL) {
9948                 type_t *return_value_type = skip_typeref(return_value->base.type);
9949
9950                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
9951                         if (is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
9952                                 /* ISO/IEC 14882:1998(E) §6.6.3:2 */
9953                                 /* Only warn in C mode, because GCC does the same */
9954                                 if (c_mode & _CXX || strict_mode) {
9955                                         errorf(pos,
9956                                                         "'return' with a value, in function returning 'void'");
9957                                 } else if (warning.other) {
9958                                         warningf(pos,
9959                                                         "'return' with a value, in function returning 'void'");
9960                                 }
9961                         } else if (!(c_mode & _CXX)) { /* ISO/IEC 14882:1998(E) §6.6.3:3 */
9962                                 /* Only warn in C mode, because GCC does the same */
9963                                 if (strict_mode) {
9964                                         errorf(pos,
9965                                                         "'return' with expression in function returning 'void'");
9966                                 } else if (warning.other) {
9967                                         warningf(pos,
9968                                                         "'return' with expression in function returning 'void'");
9969                                 }
9970                         }
9971                 } else {
9972                         assign_error_t error = semantic_assign(return_type, return_value);
9973                         report_assign_error(error, return_type, return_value, "'return'",
9974                                             pos);
9975                 }
9976                 return_value = create_implicit_cast(return_value, return_type);
9977                 /* check for returning address of a local var */
9978                 if (warning.other && return_value != NULL
9979                     && return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
9980                         const expression_t *expression = return_value->unary.value;
9981                         if (expression_is_local_variable(expression)) {
9982                                 warningf(pos, "function returns address of local variable");
9983                         }
9984                 }
9985         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
9986                 /* ISO/IEC 14882:1998(E) §6.6.3:3 */
9987                 if (c_mode & _CXX || strict_mode) {
9988                         errorf(pos,
9989                                "'return' without value, in function returning non-void");
9990                 } else {
9991                         warningf(pos,
9992                                  "'return' without value, in function returning non-void");
9993                 }
9994         }
9995         statement->returns.value = return_value;
9996
9997         expect(';', end_error);
9998
9999 end_error:
10000         return statement;
10001 }
10002
10003 /**
10004  * Parse a declaration statement.
10005  */
10006 static statement_t *parse_declaration_statement(void)
10007 {
10008         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10009
10010         entity_t *before = current_scope->last_entity;
10011         if (GNU_MODE) {
10012                 parse_external_declaration();
10013         } else {
10014                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10015         }
10016
10017         declaration_statement_t *const decl  = &statement->declaration;
10018         entity_t                *const begin =
10019                 before != NULL ? before->base.next : current_scope->entities;
10020         decl->declarations_begin = begin;
10021         decl->declarations_end   = begin != NULL ? current_scope->last_entity : NULL;
10022
10023         return statement;
10024 }
10025
10026 /**
10027  * Parse an expression statement, ie. expr ';'.
10028  */
10029 static statement_t *parse_expression_statement(void)
10030 {
10031         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10032
10033         expression_t *const expr         = parse_expression();
10034         statement->expression.expression = expr;
10035         mark_vars_read(expr, ENT_ANY);
10036
10037         expect(';', end_error);
10038
10039 end_error:
10040         return statement;
10041 }
10042
10043 /**
10044  * Parse a microsoft __try { } __finally { } or
10045  * __try{ } __except() { }
10046  */
10047 static statement_t *parse_ms_try_statment(void)
10048 {
10049         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
10050         eat(T___try);
10051
10052         PUSH_PARENT(statement);
10053
10054         ms_try_statement_t *rem = current_try;
10055         current_try = &statement->ms_try;
10056         statement->ms_try.try_statement = parse_compound_statement(false);
10057         current_try = rem;
10058
10059         POP_PARENT;
10060
10061         if (next_if(T___except)) {
10062                 expect('(', end_error);
10063                 add_anchor_token(')');
10064                 expression_t *const expr = parse_expression();
10065                 mark_vars_read(expr, NULL);
10066                 type_t       *      type = skip_typeref(expr->base.type);
10067                 if (is_type_integer(type)) {
10068                         type = promote_integer(type);
10069                 } else if (is_type_valid(type)) {
10070                         errorf(&expr->base.source_position,
10071                                "__expect expression is not an integer, but '%T'", type);
10072                         type = type_error_type;
10073                 }
10074                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
10075                 rem_anchor_token(')');
10076                 expect(')', end_error);
10077                 statement->ms_try.final_statement = parse_compound_statement(false);
10078         } else if (next_if(T__finally)) {
10079                 statement->ms_try.final_statement = parse_compound_statement(false);
10080         } else {
10081                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
10082                 return create_invalid_statement();
10083         }
10084         return statement;
10085 end_error:
10086         return create_invalid_statement();
10087 }
10088
10089 static statement_t *parse_empty_statement(void)
10090 {
10091         if (warning.empty_statement) {
10092                 warningf(HERE, "statement is empty");
10093         }
10094         statement_t *const statement = create_empty_statement();
10095         eat(';');
10096         return statement;
10097 }
10098
10099 static statement_t *parse_local_label_declaration(void)
10100 {
10101         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10102
10103         eat(T___label__);
10104
10105         entity_t *begin   = NULL;
10106         entity_t *end     = NULL;
10107         entity_t **anchor = &begin;
10108         do {
10109                 if (token.type != T_IDENTIFIER) {
10110                         parse_error_expected("while parsing local label declaration",
10111                                 T_IDENTIFIER, NULL);
10112                         goto end_error;
10113                 }
10114                 symbol_t *symbol = token.symbol;
10115                 entity_t *entity = get_entity(symbol, NAMESPACE_LABEL);
10116                 if (entity != NULL && entity->base.parent_scope == current_scope) {
10117                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition %P)",
10118                                symbol, &entity->base.source_position);
10119                 } else {
10120                         entity = allocate_entity_zero(ENTITY_LOCAL_LABEL, NAMESPACE_LABEL, symbol);
10121                         entity->base.parent_scope    = current_scope;
10122                         entity->base.source_position = token.source_position;
10123
10124                         *anchor = entity;
10125                         anchor  = &entity->base.next;
10126                         end     = entity;
10127
10128                         environment_push(entity);
10129                 }
10130                 next_token();
10131         } while (next_if(','));
10132         expect(';', end_error);
10133 end_error:
10134         statement->declaration.declarations_begin = begin;
10135         statement->declaration.declarations_end   = end;
10136         return statement;
10137 }
10138
10139 static void parse_namespace_definition(void)
10140 {
10141         eat(T_namespace);
10142
10143         entity_t *entity = NULL;
10144         symbol_t *symbol = NULL;
10145
10146         if (token.type == T_IDENTIFIER) {
10147                 symbol = token.symbol;
10148                 next_token();
10149
10150                 entity = get_entity(symbol, NAMESPACE_NORMAL);
10151                 if (entity != NULL
10152                                 && entity->kind != ENTITY_NAMESPACE
10153                                 && entity->base.parent_scope == current_scope) {
10154                         if (is_entity_valid(entity)) {
10155                                 error_redefined_as_different_kind(&token.source_position,
10156                                                 entity, ENTITY_NAMESPACE);
10157                         }
10158                         entity = NULL;
10159                 }
10160         }
10161
10162         if (entity == NULL) {
10163                 entity = allocate_entity_zero(ENTITY_NAMESPACE, NAMESPACE_NORMAL, symbol);
10164                 entity->base.source_position = token.source_position;
10165                 entity->base.parent_scope    = current_scope;
10166         }
10167
10168         if (token.type == '=') {
10169                 /* TODO: parse namespace alias */
10170                 panic("namespace alias definition not supported yet");
10171         }
10172
10173         environment_push(entity);
10174         append_entity(current_scope, entity);
10175
10176         size_t const  top       = environment_top();
10177         scope_t      *old_scope = scope_push(&entity->namespacee.members);
10178
10179         entity_t     *old_current_entity = current_entity;
10180         current_entity = entity;
10181
10182         expect('{', end_error);
10183         parse_externals();
10184         expect('}', end_error);
10185
10186 end_error:
10187         assert(current_scope == &entity->namespacee.members);
10188         assert(current_entity == entity);
10189         current_entity = old_current_entity;
10190         scope_pop(old_scope);
10191         environment_pop_to(top);
10192 }
10193
10194 /**
10195  * Parse a statement.
10196  * There's also parse_statement() which additionally checks for
10197  * "statement has no effect" warnings
10198  */
10199 static statement_t *intern_parse_statement(void)
10200 {
10201         statement_t *statement = NULL;
10202
10203         /* declaration or statement */
10204         add_anchor_token(';');
10205         switch (token.type) {
10206         case T_IDENTIFIER: {
10207                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
10208                 if (la1_type == ':') {
10209                         statement = parse_label_statement();
10210                 } else if (is_typedef_symbol(token.symbol)) {
10211                         statement = parse_declaration_statement();
10212                 } else {
10213                         /* it's an identifier, the grammar says this must be an
10214                          * expression statement. However it is common that users mistype
10215                          * declaration types, so we guess a bit here to improve robustness
10216                          * for incorrect programs */
10217                         switch (la1_type) {
10218                         case '&':
10219                         case '*':
10220                                 if (get_entity(token.symbol, NAMESPACE_NORMAL) != NULL) {
10221                         default:
10222                                         statement = parse_expression_statement();
10223                                 } else {
10224                         DECLARATION_START
10225                         case T_IDENTIFIER:
10226                                         statement = parse_declaration_statement();
10227                                 }
10228                                 break;
10229                         }
10230                 }
10231                 break;
10232         }
10233
10234         case T___extension__:
10235                 /* This can be a prefix to a declaration or an expression statement.
10236                  * We simply eat it now and parse the rest with tail recursion. */
10237                 while (next_if(T___extension__)) {}
10238                 bool old_gcc_extension = in_gcc_extension;
10239                 in_gcc_extension       = true;
10240                 statement = intern_parse_statement();
10241                 in_gcc_extension = old_gcc_extension;
10242                 break;
10243
10244         DECLARATION_START
10245                 statement = parse_declaration_statement();
10246                 break;
10247
10248         case T___label__:
10249                 statement = parse_local_label_declaration();
10250                 break;
10251
10252         case ';':         statement = parse_empty_statement();         break;
10253         case '{':         statement = parse_compound_statement(false); break;
10254         case T___leave:   statement = parse_leave_statement();         break;
10255         case T___try:     statement = parse_ms_try_statment();         break;
10256         case T_asm:       statement = parse_asm_statement();           break;
10257         case T_break:     statement = parse_break();                   break;
10258         case T_case:      statement = parse_case_statement();          break;
10259         case T_continue:  statement = parse_continue();                break;
10260         case T_default:   statement = parse_default_statement();       break;
10261         case T_do:        statement = parse_do();                      break;
10262         case T_for:       statement = parse_for();                     break;
10263         case T_goto:      statement = parse_goto();                    break;
10264         case T_if:        statement = parse_if();                      break;
10265         case T_return:    statement = parse_return();                  break;
10266         case T_switch:    statement = parse_switch();                  break;
10267         case T_while:     statement = parse_while();                   break;
10268
10269         EXPRESSION_START
10270                 statement = parse_expression_statement();
10271                 break;
10272
10273         default:
10274                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10275                 statement = create_invalid_statement();
10276                 if (!at_anchor())
10277                         next_token();
10278                 break;
10279         }
10280         rem_anchor_token(';');
10281
10282         assert(statement != NULL
10283                         && statement->base.source_position.input_name != NULL);
10284
10285         return statement;
10286 }
10287
10288 /**
10289  * parse a statement and emits "statement has no effect" warning if needed
10290  * (This is really a wrapper around intern_parse_statement with check for 1
10291  *  single warning. It is needed, because for statement expressions we have
10292  *  to avoid the warning on the last statement)
10293  */
10294 static statement_t *parse_statement(void)
10295 {
10296         statement_t *statement = intern_parse_statement();
10297
10298         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10299                 expression_t *expression = statement->expression.expression;
10300                 if (!expression_has_effect(expression)) {
10301                         warningf(&expression->base.source_position,
10302                                         "statement has no effect");
10303                 }
10304         }
10305
10306         return statement;
10307 }
10308
10309 /**
10310  * Parse a compound statement.
10311  */
10312 static statement_t *parse_compound_statement(bool inside_expression_statement)
10313 {
10314         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10315
10316         PUSH_PARENT(statement);
10317
10318         eat('{');
10319         add_anchor_token('}');
10320         /* tokens, which can start a statement */
10321         /* TODO MS, __builtin_FOO */
10322         add_anchor_token('!');
10323         add_anchor_token('&');
10324         add_anchor_token('(');
10325         add_anchor_token('*');
10326         add_anchor_token('+');
10327         add_anchor_token('-');
10328         add_anchor_token('{');
10329         add_anchor_token('~');
10330         add_anchor_token(T_CHARACTER_CONSTANT);
10331         add_anchor_token(T_COLONCOLON);
10332         add_anchor_token(T_FLOATINGPOINT);
10333         add_anchor_token(T_IDENTIFIER);
10334         add_anchor_token(T_INTEGER);
10335         add_anchor_token(T_MINUSMINUS);
10336         add_anchor_token(T_PLUSPLUS);
10337         add_anchor_token(T_STRING_LITERAL);
10338         add_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10339         add_anchor_token(T_WIDE_STRING_LITERAL);
10340         add_anchor_token(T__Bool);
10341         add_anchor_token(T__Complex);
10342         add_anchor_token(T__Imaginary);
10343         add_anchor_token(T___FUNCTION__);
10344         add_anchor_token(T___PRETTY_FUNCTION__);
10345         add_anchor_token(T___alignof__);
10346         add_anchor_token(T___attribute__);
10347         add_anchor_token(T___builtin_va_start);
10348         add_anchor_token(T___extension__);
10349         add_anchor_token(T___func__);
10350         add_anchor_token(T___imag__);
10351         add_anchor_token(T___label__);
10352         add_anchor_token(T___real__);
10353         add_anchor_token(T___thread);
10354         add_anchor_token(T_asm);
10355         add_anchor_token(T_auto);
10356         add_anchor_token(T_bool);
10357         add_anchor_token(T_break);
10358         add_anchor_token(T_case);
10359         add_anchor_token(T_char);
10360         add_anchor_token(T_class);
10361         add_anchor_token(T_const);
10362         add_anchor_token(T_const_cast);
10363         add_anchor_token(T_continue);
10364         add_anchor_token(T_default);
10365         add_anchor_token(T_delete);
10366         add_anchor_token(T_double);
10367         add_anchor_token(T_do);
10368         add_anchor_token(T_dynamic_cast);
10369         add_anchor_token(T_enum);
10370         add_anchor_token(T_extern);
10371         add_anchor_token(T_false);
10372         add_anchor_token(T_float);
10373         add_anchor_token(T_for);
10374         add_anchor_token(T_goto);
10375         add_anchor_token(T_if);
10376         add_anchor_token(T_inline);
10377         add_anchor_token(T_int);
10378         add_anchor_token(T_long);
10379         add_anchor_token(T_new);
10380         add_anchor_token(T_operator);
10381         add_anchor_token(T_register);
10382         add_anchor_token(T_reinterpret_cast);
10383         add_anchor_token(T_restrict);
10384         add_anchor_token(T_return);
10385         add_anchor_token(T_short);
10386         add_anchor_token(T_signed);
10387         add_anchor_token(T_sizeof);
10388         add_anchor_token(T_static);
10389         add_anchor_token(T_static_cast);
10390         add_anchor_token(T_struct);
10391         add_anchor_token(T_switch);
10392         add_anchor_token(T_template);
10393         add_anchor_token(T_this);
10394         add_anchor_token(T_throw);
10395         add_anchor_token(T_true);
10396         add_anchor_token(T_try);
10397         add_anchor_token(T_typedef);
10398         add_anchor_token(T_typeid);
10399         add_anchor_token(T_typename);
10400         add_anchor_token(T_typeof);
10401         add_anchor_token(T_union);
10402         add_anchor_token(T_unsigned);
10403         add_anchor_token(T_using);
10404         add_anchor_token(T_void);
10405         add_anchor_token(T_volatile);
10406         add_anchor_token(T_wchar_t);
10407         add_anchor_token(T_while);
10408
10409         size_t const  top       = environment_top();
10410         scope_t      *old_scope = scope_push(&statement->compound.scope);
10411
10412         statement_t **anchor            = &statement->compound.statements;
10413         bool          only_decls_so_far = true;
10414         while (token.type != '}') {
10415                 if (token.type == T_EOF) {
10416                         errorf(&statement->base.source_position,
10417                                "EOF while parsing compound statement");
10418                         break;
10419                 }
10420                 statement_t *sub_statement = intern_parse_statement();
10421                 if (is_invalid_statement(sub_statement)) {
10422                         /* an error occurred. if we are at an anchor, return */
10423                         if (at_anchor())
10424                                 goto end_error;
10425                         continue;
10426                 }
10427
10428                 if (warning.declaration_after_statement) {
10429                         if (sub_statement->kind != STATEMENT_DECLARATION) {
10430                                 only_decls_so_far = false;
10431                         } else if (!only_decls_so_far) {
10432                                 warningf(&sub_statement->base.source_position,
10433                                          "ISO C90 forbids mixed declarations and code");
10434                         }
10435                 }
10436
10437                 *anchor = sub_statement;
10438
10439                 while (sub_statement->base.next != NULL)
10440                         sub_statement = sub_statement->base.next;
10441
10442                 anchor = &sub_statement->base.next;
10443         }
10444         next_token();
10445
10446         /* look over all statements again to produce no effect warnings */
10447         if (warning.unused_value) {
10448                 statement_t *sub_statement = statement->compound.statements;
10449                 for (; sub_statement != NULL; sub_statement = sub_statement->base.next) {
10450                         if (sub_statement->kind != STATEMENT_EXPRESSION)
10451                                 continue;
10452                         /* don't emit a warning for the last expression in an expression
10453                          * statement as it has always an effect */
10454                         if (inside_expression_statement && sub_statement->base.next == NULL)
10455                                 continue;
10456
10457                         expression_t *expression = sub_statement->expression.expression;
10458                         if (!expression_has_effect(expression)) {
10459                                 warningf(&expression->base.source_position,
10460                                          "statement has no effect");
10461                         }
10462                 }
10463         }
10464
10465 end_error:
10466         rem_anchor_token(T_while);
10467         rem_anchor_token(T_wchar_t);
10468         rem_anchor_token(T_volatile);
10469         rem_anchor_token(T_void);
10470         rem_anchor_token(T_using);
10471         rem_anchor_token(T_unsigned);
10472         rem_anchor_token(T_union);
10473         rem_anchor_token(T_typeof);
10474         rem_anchor_token(T_typename);
10475         rem_anchor_token(T_typeid);
10476         rem_anchor_token(T_typedef);
10477         rem_anchor_token(T_try);
10478         rem_anchor_token(T_true);
10479         rem_anchor_token(T_throw);
10480         rem_anchor_token(T_this);
10481         rem_anchor_token(T_template);
10482         rem_anchor_token(T_switch);
10483         rem_anchor_token(T_struct);
10484         rem_anchor_token(T_static_cast);
10485         rem_anchor_token(T_static);
10486         rem_anchor_token(T_sizeof);
10487         rem_anchor_token(T_signed);
10488         rem_anchor_token(T_short);
10489         rem_anchor_token(T_return);
10490         rem_anchor_token(T_restrict);
10491         rem_anchor_token(T_reinterpret_cast);
10492         rem_anchor_token(T_register);
10493         rem_anchor_token(T_operator);
10494         rem_anchor_token(T_new);
10495         rem_anchor_token(T_long);
10496         rem_anchor_token(T_int);
10497         rem_anchor_token(T_inline);
10498         rem_anchor_token(T_if);
10499         rem_anchor_token(T_goto);
10500         rem_anchor_token(T_for);
10501         rem_anchor_token(T_float);
10502         rem_anchor_token(T_false);
10503         rem_anchor_token(T_extern);
10504         rem_anchor_token(T_enum);
10505         rem_anchor_token(T_dynamic_cast);
10506         rem_anchor_token(T_do);
10507         rem_anchor_token(T_double);
10508         rem_anchor_token(T_delete);
10509         rem_anchor_token(T_default);
10510         rem_anchor_token(T_continue);
10511         rem_anchor_token(T_const_cast);
10512         rem_anchor_token(T_const);
10513         rem_anchor_token(T_class);
10514         rem_anchor_token(T_char);
10515         rem_anchor_token(T_case);
10516         rem_anchor_token(T_break);
10517         rem_anchor_token(T_bool);
10518         rem_anchor_token(T_auto);
10519         rem_anchor_token(T_asm);
10520         rem_anchor_token(T___thread);
10521         rem_anchor_token(T___real__);
10522         rem_anchor_token(T___label__);
10523         rem_anchor_token(T___imag__);
10524         rem_anchor_token(T___func__);
10525         rem_anchor_token(T___extension__);
10526         rem_anchor_token(T___builtin_va_start);
10527         rem_anchor_token(T___attribute__);
10528         rem_anchor_token(T___alignof__);
10529         rem_anchor_token(T___PRETTY_FUNCTION__);
10530         rem_anchor_token(T___FUNCTION__);
10531         rem_anchor_token(T__Imaginary);
10532         rem_anchor_token(T__Complex);
10533         rem_anchor_token(T__Bool);
10534         rem_anchor_token(T_WIDE_STRING_LITERAL);
10535         rem_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10536         rem_anchor_token(T_STRING_LITERAL);
10537         rem_anchor_token(T_PLUSPLUS);
10538         rem_anchor_token(T_MINUSMINUS);
10539         rem_anchor_token(T_INTEGER);
10540         rem_anchor_token(T_IDENTIFIER);
10541         rem_anchor_token(T_FLOATINGPOINT);
10542         rem_anchor_token(T_COLONCOLON);
10543         rem_anchor_token(T_CHARACTER_CONSTANT);
10544         rem_anchor_token('~');
10545         rem_anchor_token('{');
10546         rem_anchor_token('-');
10547         rem_anchor_token('+');
10548         rem_anchor_token('*');
10549         rem_anchor_token('(');
10550         rem_anchor_token('&');
10551         rem_anchor_token('!');
10552         rem_anchor_token('}');
10553         assert(current_scope == &statement->compound.scope);
10554         scope_pop(old_scope);
10555         environment_pop_to(top);
10556
10557         POP_PARENT;
10558         return statement;
10559 }
10560
10561 /**
10562  * Check for unused global static functions and variables
10563  */
10564 static void check_unused_globals(void)
10565 {
10566         if (!warning.unused_function && !warning.unused_variable)
10567                 return;
10568
10569         for (const entity_t *entity = file_scope->entities; entity != NULL;
10570              entity = entity->base.next) {
10571                 if (!is_declaration(entity))
10572                         continue;
10573
10574                 const declaration_t *declaration = &entity->declaration;
10575                 if (declaration->used                  ||
10576                     declaration->modifiers & DM_UNUSED ||
10577                     declaration->modifiers & DM_USED   ||
10578                     declaration->storage_class != STORAGE_CLASS_STATIC)
10579                         continue;
10580
10581                 type_t *const type = declaration->type;
10582                 const char *s;
10583                 if (entity->kind == ENTITY_FUNCTION) {
10584                         /* inhibit warning for static inline functions */
10585                         if (entity->function.is_inline)
10586                                 continue;
10587
10588                         s = entity->function.statement != NULL ? "defined" : "declared";
10589                 } else {
10590                         s = "defined";
10591                 }
10592
10593                 warningf(&declaration->base.source_position, "'%#T' %s but not used",
10594                         type, declaration->base.symbol, s);
10595         }
10596 }
10597
10598 static void parse_global_asm(void)
10599 {
10600         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
10601
10602         eat(T_asm);
10603         expect('(', end_error);
10604
10605         statement->asms.asm_text = parse_string_literals();
10606         statement->base.next     = unit->global_asm;
10607         unit->global_asm         = statement;
10608
10609         expect(')', end_error);
10610         expect(';', end_error);
10611
10612 end_error:;
10613 }
10614
10615 static void parse_linkage_specification(void)
10616 {
10617         eat(T_extern);
10618
10619         source_position_t const pos     = *HERE;
10620         char const       *const linkage = parse_string_literals().begin;
10621
10622         linkage_kind_t old_linkage = current_linkage;
10623         linkage_kind_t new_linkage;
10624         if (strcmp(linkage, "C") == 0) {
10625                 new_linkage = LINKAGE_C;
10626         } else if (strcmp(linkage, "C++") == 0) {
10627                 new_linkage = LINKAGE_CXX;
10628         } else {
10629                 errorf(&pos, "linkage string \"%s\" not recognized", linkage);
10630                 new_linkage = LINKAGE_INVALID;
10631         }
10632         current_linkage = new_linkage;
10633
10634         if (next_if('{')) {
10635                 parse_externals();
10636                 expect('}', end_error);
10637         } else {
10638                 parse_external();
10639         }
10640
10641 end_error:
10642         assert(current_linkage == new_linkage);
10643         current_linkage = old_linkage;
10644 }
10645
10646 static void parse_external(void)
10647 {
10648         switch (token.type) {
10649                 DECLARATION_START_NO_EXTERN
10650                 case T_IDENTIFIER:
10651                 case T___extension__:
10652                 /* tokens below are for implicit int */
10653                 case '&': /* & x; -> int& x; (and error later, because C++ has no
10654                              implicit int) */
10655                 case '*': /* * x; -> int* x; */
10656                 case '(': /* (x); -> int (x); */
10657                         parse_external_declaration();
10658                         return;
10659
10660                 case T_extern:
10661                         if (look_ahead(1)->type == T_STRING_LITERAL) {
10662                                 parse_linkage_specification();
10663                         } else {
10664                                 parse_external_declaration();
10665                         }
10666                         return;
10667
10668                 case T_asm:
10669                         parse_global_asm();
10670                         return;
10671
10672                 case T_namespace:
10673                         parse_namespace_definition();
10674                         return;
10675
10676                 case ';':
10677                         if (!strict_mode) {
10678                                 if (warning.other)
10679                                         warningf(HERE, "stray ';' outside of function");
10680                                 next_token();
10681                                 return;
10682                         }
10683                         /* FALLTHROUGH */
10684
10685                 default:
10686                         errorf(HERE, "stray %K outside of function", &token);
10687                         if (token.type == '(' || token.type == '{' || token.type == '[')
10688                                 eat_until_matching_token(token.type);
10689                         next_token();
10690                         return;
10691         }
10692 }
10693
10694 static void parse_externals(void)
10695 {
10696         add_anchor_token('}');
10697         add_anchor_token(T_EOF);
10698
10699 #ifndef NDEBUG
10700         /* make a copy of the anchor set, so we can check if it is restored after parsing */
10701         unsigned char token_anchor_copy[T_LAST_TOKEN];
10702         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
10703 #endif
10704
10705         while (token.type != T_EOF && token.type != '}') {
10706 #ifndef NDEBUG
10707                 bool anchor_leak = false;
10708                 for (int i = 0; i < T_LAST_TOKEN; ++i) {
10709                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
10710                         if (count != 0) {
10711                                 /* the anchor set and its copy differs */
10712                                 internal_errorf(HERE, "Leaked anchor token %k %d times", i, count);
10713                                 anchor_leak = true;
10714                         }
10715                 }
10716                 if (in_gcc_extension) {
10717                         /* an gcc extension scope was not closed */
10718                         internal_errorf(HERE, "Leaked __extension__");
10719                         anchor_leak = true;
10720                 }
10721
10722                 if (anchor_leak)
10723                         abort();
10724 #endif
10725
10726                 parse_external();
10727         }
10728
10729         rem_anchor_token(T_EOF);
10730         rem_anchor_token('}');
10731 }
10732
10733 /**
10734  * Parse a translation unit.
10735  */
10736 static void parse_translation_unit(void)
10737 {
10738         add_anchor_token(T_EOF);
10739
10740         while (true) {
10741                 parse_externals();
10742
10743                 if (token.type == T_EOF)
10744                         break;
10745
10746                 errorf(HERE, "stray %K outside of function", &token);
10747                 if (token.type == '(' || token.type == '{' || token.type == '[')
10748                         eat_until_matching_token(token.type);
10749                 next_token();
10750         }
10751 }
10752
10753 void set_default_visibility(elf_visibility_tag_t visibility)
10754 {
10755         default_visibility = visibility;
10756 }
10757
10758 /**
10759  * Parse the input.
10760  *
10761  * @return  the translation unit or NULL if errors occurred.
10762  */
10763 void start_parsing(void)
10764 {
10765         environment_stack = NEW_ARR_F(stack_entry_t, 0);
10766         label_stack       = NEW_ARR_F(stack_entry_t, 0);
10767         diagnostic_count  = 0;
10768         error_count       = 0;
10769         warning_count     = 0;
10770
10771         print_to_file(stderr);
10772
10773         assert(unit == NULL);
10774         unit = allocate_ast_zero(sizeof(unit[0]));
10775
10776         assert(file_scope == NULL);
10777         file_scope = &unit->scope;
10778
10779         assert(current_scope == NULL);
10780         scope_push(&unit->scope);
10781
10782         create_gnu_builtins();
10783         if (c_mode & _MS)
10784                 create_microsoft_intrinsics();
10785 }
10786
10787 translation_unit_t *finish_parsing(void)
10788 {
10789         assert(current_scope == &unit->scope);
10790         scope_pop(NULL);
10791
10792         assert(file_scope == &unit->scope);
10793         check_unused_globals();
10794         file_scope = NULL;
10795
10796         DEL_ARR_F(environment_stack);
10797         DEL_ARR_F(label_stack);
10798
10799         translation_unit_t *result = unit;
10800         unit = NULL;
10801         return result;
10802 }
10803
10804 /* §6.9.2:2 and §6.9.2:5: At the end of the translation incomplete arrays
10805  * are given length one. */
10806 static void complete_incomplete_arrays(void)
10807 {
10808         size_t n = ARR_LEN(incomplete_arrays);
10809         for (size_t i = 0; i != n; ++i) {
10810                 declaration_t *const decl      = incomplete_arrays[i];
10811                 type_t        *const orig_type = decl->type;
10812                 type_t        *const type      = skip_typeref(orig_type);
10813
10814                 if (!is_type_incomplete(type))
10815                         continue;
10816
10817                 if (warning.other) {
10818                         warningf(&decl->base.source_position,
10819                                         "array '%#T' assumed to have one element",
10820                                         orig_type, decl->base.symbol);
10821                 }
10822
10823                 type_t *const new_type = duplicate_type(type);
10824                 new_type->array.size_constant     = true;
10825                 new_type->array.has_implicit_size = true;
10826                 new_type->array.size              = 1;
10827
10828                 type_t *const result = identify_new_type(new_type);
10829
10830                 decl->type = result;
10831         }
10832 }
10833
10834 void prepare_main_collect2(entity_t *entity)
10835 {
10836         // create call to __main
10837         symbol_t *symbol         = symbol_table_insert("__main");
10838         entity_t *subsubmain_ent
10839                 = create_implicit_function(symbol, &builtin_source_position);
10840
10841         expression_t *ref         = allocate_expression_zero(EXPR_REFERENCE);
10842         type_t       *ftype       = subsubmain_ent->declaration.type;
10843         ref->base.source_position = builtin_source_position;
10844         ref->base.type            = make_pointer_type(ftype, TYPE_QUALIFIER_NONE);
10845         ref->reference.entity     = subsubmain_ent;
10846
10847         expression_t *call = allocate_expression_zero(EXPR_CALL);
10848         call->base.source_position = builtin_source_position;
10849         call->base.type            = type_void;
10850         call->call.function        = ref;
10851
10852         statement_t *expr_statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10853         expr_statement->base.source_position  = builtin_source_position;
10854         expr_statement->expression.expression = call;
10855
10856         statement_t *statement = entity->function.statement;
10857         assert(statement->kind == STATEMENT_COMPOUND);
10858         compound_statement_t *compounds = &statement->compound;
10859
10860         expr_statement->base.next = compounds->statements;
10861         compounds->statements     = expr_statement;
10862 }
10863
10864 void parse(void)
10865 {
10866         lookahead_bufpos = 0;
10867         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
10868                 next_token();
10869         }
10870         current_linkage   = c_mode & _CXX ? LINKAGE_CXX : LINKAGE_C;
10871         incomplete_arrays = NEW_ARR_F(declaration_t*, 0);
10872         parse_translation_unit();
10873         complete_incomplete_arrays();
10874         DEL_ARR_F(incomplete_arrays);
10875         incomplete_arrays = NULL;
10876 }
10877
10878 /**
10879  * Initialize the parser.
10880  */
10881 void init_parser(void)
10882 {
10883         sym_anonymous = symbol_table_insert("<anonymous>");
10884
10885         memset(token_anchor_set, 0, sizeof(token_anchor_set));
10886
10887         init_expression_parsers();
10888         obstack_init(&temp_obst);
10889 }
10890
10891 /**
10892  * Terminate the parser.
10893  */
10894 void exit_parser(void)
10895 {
10896         obstack_free(&temp_obst, NULL);
10897 }