nsz Git - cparser/blob - parser.c

   1 #include <config.h>
   2
   3 #include <assert.h>
   4 #include <stdarg.h>
   5 #include <stdbool.h>
   6
   7 #include "diagnostic.h"
   8 #include "format_check.h"
   9 #include "parser.h"
  10 #include "lexer.h"
  11 #include "token_t.h"
  12 #include "types.h"
  13 #include "type_t.h"
  14 #include "type_hash.h"
  15 #include "ast_t.h"
  16 #include "lang_features.h"
  17 #include "warning.h"
  18 #include "adt/bitfiddle.h"
  19 #include "adt/error.h"
  20 #include "adt/array.h"
  21
  22 //#define PRINT_TOKENS
  23 #define MAX_LOOKAHEAD 2
  24
  25 typedef struct {
  26         declaration_t *old_declaration;
  27         symbol_t      *symbol;
  28         unsigned short namespc;
  29 } stack_entry_t;
  30
  31 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  32 struct declaration_specifiers_t {
  33         source_position_t  source_position;
  34         unsigned char      storage_class;
  35         bool               is_inline;
  36         decl_modifiers_t   decl_modifiers;
  37         type_t            *type;
  38 };
  39
  40 typedef declaration_t* (*parsed_declaration_func) (declaration_t *declaration);
  41
  42 static token_t             token;
  43 static token_t             lookahead_buffer[MAX_LOOKAHEAD];
  44 static int                 lookahead_bufpos;
  45 static stack_entry_t      *environment_stack = NULL;
  46 static stack_entry_t      *label_stack       = NULL;
  47 static context_t          *global_context    = NULL;
  48 static context_t          *context           = NULL;
  49 static declaration_t      *last_declaration  = NULL;
  50 static declaration_t      *current_function  = NULL;
  51 static switch_statement_t *current_switch    = NULL;
  52 static statement_t        *current_loop      = NULL;
  53 static goto_statement_t   *goto_first        = NULL;
  54 static goto_statement_t   *goto_last         = NULL;
  55 static struct obstack  temp_obst;
  56
  57 /** The current source position. */
  58 #define HERE token.source_position
  59
  60 static type_t *type_valist;
  61
  62 static statement_t *parse_compound_statement(void);
  63 static statement_t *parse_statement(void);
  64
  65 static expression_t *parse_sub_expression(unsigned precedence);
  66 static expression_t *parse_expression(void);
  67 static type_t       *parse_typename(void);
  68
  69 static void parse_compound_type_entries(void);
  70 static declaration_t *parse_declarator(
  71                 const declaration_specifiers_t *specifiers, bool may_be_abstract);
  72 static declaration_t *record_declaration(declaration_t *declaration);
  73
  74 static void semantic_comparison(binary_expression_t *expression);
  75
  76 #define STORAGE_CLASSES     \
  77         case T_typedef:         \
  78         case T_extern:          \
  79         case T_static:          \
  80         case T_auto:            \
  81         case T_register:
  82
  83 #define TYPE_QUALIFIERS     \
  84         case T_const:           \
  85         case T_restrict:        \
  86         case T_volatile:        \
  87         case T_inline:          \
  88         case T_forceinline:
  89
  90 #ifdef PROVIDE_COMPLEX
  91 #define COMPLEX_SPECIFIERS  \
  92         case T__Complex:
  93 #define IMAGINARY_SPECIFIERS \
  94         case T__Imaginary:
  95 #else
  96 #define COMPLEX_SPECIFIERS
  97 #define IMAGINARY_SPECIFIERS
  98 #endif
  99
 100 #define TYPE_SPECIFIERS       \
 101         case T_void:              \
 102         case T_char:              \
 103         case T_short:             \
 104         case T_int:               \
 105         case T_long:              \
 106         case T_float:             \
 107         case T_double:            \
 108         case T_signed:            \
 109         case T_unsigned:          \
 110         case T__Bool:             \
 111         case T_struct:            \
 112         case T_union:             \
 113         case T_enum:              \
 114         case T___typeof__:        \
 115         case T___builtin_va_list: \
 116         COMPLEX_SPECIFIERS        \
 117         IMAGINARY_SPECIFIERS
 118
 119 #define DECLARATION_START   \
 120         STORAGE_CLASSES         \
 121         TYPE_QUALIFIERS         \
 122         TYPE_SPECIFIERS
 123
 124 #define TYPENAME_START      \
 125         TYPE_QUALIFIERS         \
 126         TYPE_SPECIFIERS
 127
 128 /**
 129  * Allocate an AST node with given size and
 130  * initialize all fields with zero.
 131  */
 132 static void *allocate_ast_zero(size_t size)
 133 {
 134         void *res = allocate_ast(size);
 135         memset(res, 0, size);
 136         return res;
 137 }
 138
 139 static declaration_t *allocate_declaration_zero(void)
 140 {
 141         declaration_t *declaration = allocate_ast_zero(sizeof(*allocate_declaration_zero()));
 142         declaration->type = type_error_type;
 143         return declaration;
 144 }
 145
 146 /**
 147  * Returns the size of a statement node.
 148  *
 149  * @param kind  the statement kind
 150  */
 151 static size_t get_statement_struct_size(statement_kind_t kind)
 152 {
 153         static const size_t sizes[] = {
 154                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 155                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 156                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 157                 [STATEMENT_IF]          = sizeof(if_statement_t),
 158                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 159                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 160                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 161                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 162                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 163                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 164                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 165                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 166                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 167                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 168                 [STATEMENT_ASM]         = sizeof(asm_statement_t)
 169         };
 170         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 171         assert(sizes[kind] != 0);
 172         return sizes[kind];
 173 }
 174
 175 /**
 176  * Allocate a statement node of given kind and initialize all
 177  * fields with zero.
 178  */
 179 static statement_t *allocate_statement_zero(statement_kind_t kind)
 180 {
 181         size_t       size = get_statement_struct_size(kind);
 182         statement_t *res  = allocate_ast_zero(size);
 183
 184         res->base.kind = kind;
 185         return res;
 186 }
 187
 188 /**
 189  * Returns the size of an expression node.
 190  *
 191  * @param kind  the expression kind
 192  */
 193 static size_t get_expression_struct_size(expression_kind_t kind)
 194 {
 195         static const size_t sizes[] = {
 196                 [EXPR_INVALID]             = sizeof(expression_base_t),
 197                 [EXPR_REFERENCE]           = sizeof(reference_expression_t),
 198                 [EXPR_CONST]               = sizeof(const_expression_t),
 199                 [EXPR_STRING_LITERAL]      = sizeof(string_literal_expression_t),
 200                 [EXPR_WIDE_STRING_LITERAL] = sizeof(wide_string_literal_expression_t),
 201                 [EXPR_CALL]                = sizeof(call_expression_t),
 202                 [EXPR_UNARY_FIRST]         = sizeof(unary_expression_t),
 203                 [EXPR_BINARY_FIRST]        = sizeof(binary_expression_t),
 204                 [EXPR_CONDITIONAL]         = sizeof(conditional_expression_t),
 205                 [EXPR_SELECT]              = sizeof(select_expression_t),
 206                 [EXPR_ARRAY_ACCESS]        = sizeof(array_access_expression_t),
 207                 [EXPR_SIZEOF]              = sizeof(sizeof_expression_t),
 208                 [EXPR_CLASSIFY_TYPE]       = sizeof(classify_type_expression_t),
 209                 [EXPR_FUNCTION]            = sizeof(string_literal_expression_t),
 210                 [EXPR_PRETTY_FUNCTION]     = sizeof(string_literal_expression_t),
 211                 [EXPR_BUILTIN_SYMBOL]      = sizeof(builtin_symbol_expression_t),
 212                 [EXPR_BUILTIN_CONSTANT_P]  = sizeof(builtin_constant_expression_t),
 213                 [EXPR_BUILTIN_PREFETCH]    = sizeof(builtin_prefetch_expression_t),
 214                 [EXPR_OFFSETOF]            = sizeof(offsetof_expression_t),
 215                 [EXPR_VA_START]            = sizeof(va_start_expression_t),
 216                 [EXPR_VA_ARG]              = sizeof(va_arg_expression_t),
 217                 [EXPR_STATEMENT]           = sizeof(statement_expression_t),
 218         };
 219         if(kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 220                 return sizes[EXPR_UNARY_FIRST];
 221         }
 222         if(kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 223                 return sizes[EXPR_BINARY_FIRST];
 224         }
 225         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 226         assert(sizes[kind] != 0);
 227         return sizes[kind];
 228 }
 229
 230 /**
 231  * Allocate an expression node of given kind and initialize all
 232  * fields with zero.
 233  */
 234 static expression_t *allocate_expression_zero(expression_kind_t kind)
 235 {
 236         size_t        size = get_expression_struct_size(kind);
 237         expression_t *res  = allocate_ast_zero(size);
 238
 239         res->base.kind     = kind;
 240         res->base.datatype = type_error_type;
 241         return res;
 242 }
 243
 244 /**
 245  * Returns the size of a type node.
 246  *
 247  * @param kind  the type kind
 248  */
 249 static size_t get_type_struct_size(type_kind_t kind)
 250 {
 251         static const size_t sizes[] = {
 252                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 253                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 254                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 255                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 256                 [TYPE_ENUM]            = sizeof(enum_type_t),
 257                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 258                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 259                 [TYPE_ARRAY]           = sizeof(array_type_t),
 260                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 261                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 262                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 263         };
 264         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 265         assert(kind <= TYPE_TYPEOF);
 266         assert(sizes[kind] != 0);
 267         return sizes[kind];
 268 }
 269
 270 /**
 271  * Allocate a type node of given kind and initialize all
 272  * fields with zero.
 273  */
 274 static type_t *allocate_type_zero(type_kind_t kind)
 275 {
 276         size_t  size = get_type_struct_size(kind);
 277         type_t *res  = obstack_alloc(type_obst, size);
 278         memset(res, 0, size);
 279
 280         res->base.kind = kind;
 281         return res;
 282 }
 283
 284 /**
 285  * Returns the size of an initializer node.
 286  *
 287  * @param kind  the initializer kind
 288  */
 289 static size_t get_initializer_size(initializer_kind_t kind)
 290 {
 291         static const size_t sizes[] = {
 292                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 293                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 294                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 295                 [INITIALIZER_LIST]        = sizeof(initializer_list_t)
 296         };
 297         assert(kind < sizeof(sizes) / sizeof(*sizes));
 298         assert(sizes[kind] != 0);
 299         return sizes[kind];
 300 }
 301
 302 /**
 303  * Allocate an initializer node of given kind and initialize all
 304  * fields with zero.
 305  */
 306 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 307 {
 308         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 309         result->kind          = kind;
 310
 311         return result;
 312 }
 313
 314 /**
 315  * Free a type from the type obstack.
 316  */
 317 static void free_type(void *type)
 318 {
 319         obstack_free(type_obst, type);
 320 }
 321
 322 /**
 323  * Returns the index of the top element of the environment stack.
 324  */
 325 static size_t environment_top(void)
 326 {
 327         return ARR_LEN(environment_stack);
 328 }
 329
 330 /**
 331  * Returns the index of the top element of the label stack.
 332  */
 333 static size_t label_top(void)
 334 {
 335         return ARR_LEN(label_stack);
 336 }
 337
 338
 339 /**
 340  * Return the next token.
 341  */
 342 static inline void next_token(void)
 343 {
 344         token                              = lookahead_buffer[lookahead_bufpos];
 345         lookahead_buffer[lookahead_bufpos] = lexer_token;
 346         lexer_next_token();
 347
 348         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 349
 350 #ifdef PRINT_TOKENS
 351         print_token(stderr, &token);
 352         fprintf(stderr, "\n");
 353 #endif
 354 }
 355
 356 /**
 357  * Return the next token with a given lookahead.
 358  */
 359 static inline const token_t *look_ahead(int num)
 360 {
 361         assert(num > 0 && num <= MAX_LOOKAHEAD);
 362         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 363         return &lookahead_buffer[pos];
 364 }
 365
 366 #define eat(token_type)  do { assert(token.type == token_type); next_token(); } while(0)
 367
 368 /**
 369  * Report a parse error because an expected token was not found.
 370  */
 371 static void parse_error_expected(const char *message, ...)
 372 {
 373         if(message != NULL) {
 374                 errorf(HERE, "%s", message);
 375         }
 376         va_list ap;
 377         va_start(ap, message);
 378         errorf(HERE, "got '%K', expected %#k", &token, &ap, ", ");
 379         va_end(ap);
 380 }
 381
 382 /**
 383  * Report a type error.
 384  */
 385 static void type_error(const char *msg, const source_position_t source_position,
 386                        type_t *type)
 387 {
 388         errorf(source_position, "%s, but found type '%T'", msg, type);
 389 }
 390
 391 /**
 392  * Report an incompatible type.
 393  */
 394 static void type_error_incompatible(const char *msg,
 395                 const source_position_t source_position, type_t *type1, type_t *type2)
 396 {
 397         errorf(source_position, "%s, incompatible types: '%T' - '%T'", msg, type1, type2);
 398 }
 399
 400 /**
 401  * Eat an complete block, ie. '{ ... }'.
 402  */
 403 static void eat_block(void)
 404 {
 405         if(token.type == '{')
 406                 next_token();
 407
 408         while(token.type != '}') {
 409                 if(token.type == T_EOF)
 410                         return;
 411                 if(token.type == '{') {
 412                         eat_block();
 413                         continue;
 414                 }
 415                 next_token();
 416         }
 417         eat('}');
 418 }
 419
 420 /**
 421  * Eat a statement until an ';' token.
 422  */
 423 static void eat_statement(void)
 424 {
 425         while(token.type != ';') {
 426                 if(token.type == T_EOF)
 427                         return;
 428                 if(token.type == '}')
 429                         return;
 430                 if(token.type == '{') {
 431                         eat_block();
 432                         continue;
 433                 }
 434                 next_token();
 435         }
 436         eat(';');
 437 }
 438
 439 /**
 440  * Eat a parenthesed term, ie. '( ... )'.
 441  */
 442 static void eat_paren(void)
 443 {
 444         if(token.type == '(')
 445                 next_token();
 446
 447         while(token.type != ')') {
 448                 if(token.type == T_EOF)
 449                         return;
 450                 if(token.type == ')' || token.type == ';' || token.type == '}') {
 451                         return;
 452                 }
 453                 if(token.type == '(') {
 454                         eat_paren();
 455                         continue;
 456                 }
 457                 if(token.type == '{') {
 458                         eat_block();
 459                         continue;
 460                 }
 461                 next_token();
 462         }
 463         eat(')');
 464 }
 465
 466 #define expect(expected)                           \
 467     if(UNLIKELY(token.type != (expected))) {       \
 468         parse_error_expected(NULL, (expected), 0); \
 469         eat_statement();                           \
 470         return NULL;                               \
 471     }                                              \
 472     next_token();
 473
 474 #define expect_block(expected)                     \
 475     if(UNLIKELY(token.type != (expected))) {       \
 476         parse_error_expected(NULL, (expected), 0); \
 477         eat_block();                               \
 478         return NULL;                               \
 479     }                                              \
 480     next_token();
 481
 482 #define expect_void(expected)                      \
 483     if(UNLIKELY(token.type != (expected))) {       \
 484         parse_error_expected(NULL, (expected), 0); \
 485         eat_statement();                           \
 486         return;                                    \
 487     }                                              \
 488     next_token();
 489
 490 static void set_context(context_t *new_context)
 491 {
 492         context = new_context;
 493
 494         last_declaration = new_context->declarations;
 495         if(last_declaration != NULL) {
 496                 while(last_declaration->next != NULL) {
 497                         last_declaration = last_declaration->next;
 498                 }
 499         }
 500 }
 501
 502 /**
 503  * Search a symbol in a given namespace and returns its declaration or
 504  * NULL if this symbol was not found.
 505  */
 506 static declaration_t *get_declaration(const symbol_t *const symbol, const namespace_t namespc)
 507 {
 508         declaration_t *declaration = symbol->declaration;
 509         for( ; declaration != NULL; declaration = declaration->symbol_next) {
 510                 if(declaration->namespc == namespc)
 511                         return declaration;
 512         }
 513
 514         return NULL;
 515 }
 516
 517 /**
 518  * pushs an environment_entry on the environment stack and links the
 519  * corresponding symbol to the new entry
 520  */
 521 static void stack_push(stack_entry_t **stack_ptr, declaration_t *declaration)
 522 {
 523         symbol_t    *symbol    = declaration->symbol;
 524         namespace_t  namespc = (namespace_t)declaration->namespc;
 525
 526         /* remember old declaration */
 527         stack_entry_t entry;
 528         entry.symbol          = symbol;
 529         entry.old_declaration = symbol->declaration;
 530         entry.namespc         = (unsigned short) namespc;
 531         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 532
 533         /* replace/add declaration into declaration list of the symbol */
 534         if(symbol->declaration == NULL) {
 535                 symbol->declaration = declaration;
 536         } else {
 537                 declaration_t *iter_last = NULL;
 538                 declaration_t *iter      = symbol->declaration;
 539                 for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 540                         /* replace an entry? */
 541                         if(iter->namespc == namespc) {
 542                                 if(iter_last == NULL) {
 543                                         symbol->declaration = declaration;
 544                                 } else {
 545                                         iter_last->symbol_next = declaration;
 546                                 }
 547                                 declaration->symbol_next = iter->symbol_next;
 548                                 break;
 549                         }
 550                 }
 551                 if(iter == NULL) {
 552                         assert(iter_last->symbol_next == NULL);
 553                         iter_last->symbol_next = declaration;
 554                 }
 555         }
 556 }
 557
 558 static void environment_push(declaration_t *declaration)
 559 {
 560         assert(declaration->source_position.input_name != NULL);
 561         assert(declaration->parent_context != NULL);
 562         stack_push(&environment_stack, declaration);
 563 }
 564
 565 static void label_push(declaration_t *declaration)
 566 {
 567         declaration->parent_context = &current_function->context;
 568         stack_push(&label_stack, declaration);
 569 }
 570
 571 /**
 572  * pops symbols from the environment stack until @p new_top is the top element
 573  */
 574 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 575 {
 576         stack_entry_t *stack = *stack_ptr;
 577         size_t         top   = ARR_LEN(stack);
 578         size_t         i;
 579
 580         assert(new_top <= top);
 581         if(new_top == top)
 582                 return;
 583
 584         for(i = top; i > new_top; --i) {
 585                 stack_entry_t *entry = &stack[i - 1];
 586
 587                 declaration_t *old_declaration = entry->old_declaration;
 588                 symbol_t      *symbol          = entry->symbol;
 589                 namespace_t    namespc         = (namespace_t)entry->namespc;
 590
 591                 /* replace/remove declaration */
 592                 declaration_t *declaration = symbol->declaration;
 593                 assert(declaration != NULL);
 594                 if(declaration->namespc == namespc) {
 595                         if(old_declaration == NULL) {
 596                                 symbol->declaration = declaration->symbol_next;
 597                         } else {
 598                                 symbol->declaration = old_declaration;
 599                         }
 600                 } else {
 601                         declaration_t *iter_last = declaration;
 602                         declaration_t *iter      = declaration->symbol_next;
 603                         for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 604                                 /* replace an entry? */
 605                                 if(iter->namespc == namespc) {
 606                                         assert(iter_last != NULL);
 607                                         iter_last->symbol_next = old_declaration;
 608                                         old_declaration->symbol_next = iter->symbol_next;
 609                                         break;
 610                                 }
 611                         }
 612                         assert(iter != NULL);
 613                 }
 614         }
 615
 616         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 617 }
 618
 619 static void environment_pop_to(size_t new_top)
 620 {
 621         stack_pop_to(&environment_stack, new_top);
 622 }
 623
 624 static void label_pop_to(size_t new_top)
 625 {
 626         stack_pop_to(&label_stack, new_top);
 627 }
 628
 629
 630 static int get_rank(const type_t *type)
 631 {
 632         assert(!is_typeref(type));
 633         /* The C-standard allows promoting to int or unsigned int (see § 7.2.2
 634          * and esp. footnote 108). However we can't fold constants (yet), so we
 635          * can't decide whether unsigned int is possible, while int always works.
 636          * (unsigned int would be preferable when possible... for stuff like
 637          *  struct { enum { ... } bla : 4; } ) */
 638         if(type->kind == TYPE_ENUM)
 639                 return ATOMIC_TYPE_INT;
 640
 641         assert(type->kind == TYPE_ATOMIC);
 642         return type->atomic.akind;
 643 }
 644
 645 static type_t *promote_integer(type_t *type)
 646 {
 647         if(type->kind == TYPE_BITFIELD)
 648                 type = type->bitfield.base;
 649
 650         if(get_rank(type) < ATOMIC_TYPE_INT)
 651                 type = type_int;
 652
 653         return type;
 654 }
 655
 656 /**
 657  * Create a cast expression.
 658  *
 659  * @param expression  the expression to cast
 660  * @param dest_type   the destination type
 661  */
 662 static expression_t *create_cast_expression(expression_t *expression,
 663                                             type_t *dest_type)
 664 {
 665         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
 666
 667         cast->unary.value   = expression;
 668         cast->base.datatype = dest_type;
 669
 670         return cast;
 671 }
 672
 673 /**
 674  * Check if a given expression represents the 0 pointer constant.
 675  */
 676 static bool is_null_pointer_constant(const expression_t *expression)
 677 {
 678         /* skip void* cast */
 679         if(expression->kind == EXPR_UNARY_CAST
 680                         || expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
 681                 expression = expression->unary.value;
 682         }
 683
 684         /* TODO: not correct yet, should be any constant integer expression
 685          * which evaluates to 0 */
 686         if (expression->kind != EXPR_CONST)
 687                 return false;
 688
 689         type_t *const type = skip_typeref(expression->base.datatype);
 690         if (!is_type_integer(type))
 691                 return false;
 692
 693         return expression->conste.v.int_value == 0;
 694 }
 695
 696 /**
 697  * Create an implicit cast expression.
 698  *
 699  * @param expression  the expression to cast
 700  * @param dest_type   the destination type
 701  */
 702 static expression_t *create_implicit_cast(expression_t *expression,
 703                                           type_t *dest_type)
 704 {
 705         type_t *const source_type = expression->base.datatype;
 706
 707         if (source_type == dest_type)
 708                 return expression;
 709
 710         return create_cast_expression(expression, dest_type);
 711 }
 712
 713 /** Implements the rules from § 6.5.16.1 */
 714 static type_t *semantic_assign(type_t *orig_type_left,
 715                             const expression_t *const right,
 716                             const char *context)
 717 {
 718         type_t *const orig_type_right = right->base.datatype;
 719         type_t *const type_left       = skip_typeref(orig_type_left);
 720         type_t *const type_right      = skip_typeref(orig_type_right);
 721
 722         if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
 723             (is_type_pointer(type_left) && is_null_pointer_constant(right)) ||
 724             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
 725                 && is_type_pointer(type_right))) {
 726                 return orig_type_left;
 727         }
 728
 729         if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
 730                 type_t *points_to_left  = skip_typeref(type_left->pointer.points_to);
 731                 type_t *points_to_right = skip_typeref(type_right->pointer.points_to);
 732
 733                 /* the left type has all qualifiers from the right type */
 734                 unsigned missing_qualifiers
 735                         = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
 736                 if(missing_qualifiers != 0) {
 737                         errorf(HERE, "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointed-to type", type_left, context, type_right, missing_qualifiers);
 738                         return orig_type_left;
 739                 }
 740
 741                 points_to_left  = get_unqualified_type(points_to_left);
 742                 points_to_right = get_unqualified_type(points_to_right);
 743
 744                 if(!is_type_atomic(points_to_left, ATOMIC_TYPE_VOID)
 745                                 && !is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)
 746                                 && !types_compatible(points_to_left, points_to_right)) {
 747                         return NULL;
 748                 }
 749
 750                 return orig_type_left;
 751         }
 752
 753         if (is_type_compound(type_left)  && is_type_compound(type_right)) {
 754                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
 755                 type_t *const unqual_type_right = get_unqualified_type(type_right);
 756                 if (types_compatible(unqual_type_left, unqual_type_right)) {
 757                         return orig_type_left;
 758                 }
 759         }
 760
 761         if (!is_type_valid(type_left))
 762                 return type_left;
 763
 764         if (!is_type_valid(type_right))
 765                 return orig_type_right;
 766
 767         return NULL;
 768 }
 769
 770 static expression_t *parse_constant_expression(void)
 771 {
 772         /* start parsing at precedence 7 (conditional expression) */
 773         expression_t *result = parse_sub_expression(7);
 774
 775         if(!is_constant_expression(result)) {
 776                 errorf(result->base.source_position, "expression '%E' is not constant\n", result);
 777         }
 778
 779         return result;
 780 }
 781
 782 static expression_t *parse_assignment_expression(void)
 783 {
 784         /* start parsing at precedence 2 (assignment expression) */
 785         return parse_sub_expression(2);
 786 }
 787
 788 static type_t *make_global_typedef(const char *name, type_t *type)
 789 {
 790         symbol_t *const symbol       = symbol_table_insert(name);
 791
 792         declaration_t *const declaration = allocate_declaration_zero();
 793         declaration->namespc         = NAMESPACE_NORMAL;
 794         declaration->storage_class   = STORAGE_CLASS_TYPEDEF;
 795         declaration->type            = type;
 796         declaration->symbol          = symbol;
 797         declaration->source_position = builtin_source_position;
 798
 799         record_declaration(declaration);
 800
 801         type_t *typedef_type               = allocate_type_zero(TYPE_TYPEDEF);
 802         typedef_type->typedeft.declaration = declaration;
 803
 804         return typedef_type;
 805 }
 806
 807 static string_t parse_string_literals(void)
 808 {
 809         assert(token.type == T_STRING_LITERAL);
 810         string_t result = token.v.string;
 811
 812         next_token();
 813
 814         while (token.type == T_STRING_LITERAL) {
 815                 result = concat_strings(&result, &token.v.string);
 816                 next_token();
 817         }
 818
 819         return result;
 820 }
 821
 822 static void parse_attributes(void)
 823 {
 824         while(true) {
 825                 switch(token.type) {
 826                 case T___attribute__: {
 827                         next_token();
 828
 829                         expect_void('(');
 830                         int depth = 1;
 831                         while(depth > 0) {
 832                                 switch(token.type) {
 833                                 case T_EOF:
 834                                         errorf(HERE, "EOF while parsing attribute");
 835                                         break;
 836                                 case '(':
 837                                         next_token();
 838                                         depth++;
 839                                         break;
 840                                 case ')':
 841                                         next_token();
 842                                         depth--;
 843                                         break;
 844                                 default:
 845                                         next_token();
 846                                 }
 847                         }
 848                         break;
 849                 }
 850                 case T_asm:
 851                         next_token();
 852                         expect_void('(');
 853                         if(token.type != T_STRING_LITERAL) {
 854                                 parse_error_expected("while parsing assembler attribute",
 855                                                      T_STRING_LITERAL);
 856                                 eat_paren();
 857                                 break;
 858                         } else {
 859                                 parse_string_literals();
 860                         }
 861                         expect_void(')');
 862                         break;
 863                 default:
 864                         goto attributes_finished;
 865                 }
 866         }
 867
 868 attributes_finished:
 869         ;
 870 }
 871
 872 #if 0
 873 static designator_t *parse_designation(void)
 874 {
 875         if(token.type != '[' && token.type != '.')
 876                 return NULL;
 877
 878         designator_t *result = NULL;
 879         designator_t *last   = NULL;
 880
 881         while(1) {
 882                 designator_t *designator;
 883                 switch(token.type) {
 884                 case '[':
 885                         designator = allocate_ast_zero(sizeof(designator[0]));
 886                         next_token();
 887                         designator->array_access = parse_constant_expression();
 888                         expect(']');
 889                         break;
 890                 case '.':
 891                         designator = allocate_ast_zero(sizeof(designator[0]));
 892                         next_token();
 893                         if(token.type != T_IDENTIFIER) {
 894                                 parse_error_expected("while parsing designator",
 895                                                      T_IDENTIFIER, 0);
 896                                 return NULL;
 897                         }
 898                         designator->symbol = token.v.symbol;
 899                         next_token();
 900                         break;
 901                 default:
 902                         expect('=');
 903                         return result;
 904                 }
 905
 906                 assert(designator != NULL);
 907                 if(last != NULL) {
 908                         last->next = designator;
 909                 } else {
 910                         result = designator;
 911                 }
 912                 last = designator;
 913         }
 914 }
 915 #endif
 916
 917 static initializer_t *initializer_from_string(array_type_t *type,
 918                                               const string_t *const string)
 919 {
 920         /* TODO: check len vs. size of array type */
 921         (void) type;
 922
 923         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
 924         initializer->string.string = *string;
 925
 926         return initializer;
 927 }
 928
 929 static initializer_t *initializer_from_wide_string(array_type_t *const type,
 930                                                    wide_string_t *const string)
 931 {
 932         /* TODO: check len vs. size of array type */
 933         (void) type;
 934
 935         initializer_t *const initializer =
 936                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
 937         initializer->wide_string.string = *string;
 938
 939         return initializer;
 940 }
 941
 942 static initializer_t *initializer_from_expression(type_t *type,
 943                                                   expression_t *expression)
 944 {
 945         /* TODO check that expression is a constant expression */
 946
 947         /* § 6.7.8.14/15 char array may be initialized by string literals */
 948         type_t *const expr_type = expression->base.datatype;
 949         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
 950                 array_type_t *const array_type   = &type->array;
 951                 type_t       *const element_type = skip_typeref(array_type->element_type);
 952
 953                 if (element_type->kind == TYPE_ATOMIC) {
 954                         switch (expression->kind) {
 955                                 case EXPR_STRING_LITERAL:
 956                                         if (element_type->atomic.akind == ATOMIC_TYPE_CHAR) {
 957                                                 return initializer_from_string(array_type,
 958                                                         &expression->string.value);
 959                                         }
 960
 961                                 case EXPR_WIDE_STRING_LITERAL: {
 962                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
 963                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
 964                                                 return initializer_from_wide_string(array_type,
 965                                                         &expression->wide_string.value);
 966                                         }
 967                                 }
 968
 969                                 default:
 970                                         break;
 971                         }
 972                 }
 973         }
 974
 975         type_t *const res_type = semantic_assign(type, expression, "initializer");
 976         if (res_type == NULL)
 977                 return NULL;
 978
 979         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
 980         result->value.value = create_implicit_cast(expression, res_type);
 981
 982         return result;
 983 }
 984
 985 static initializer_t *parse_sub_initializer(type_t *type,
 986                                             expression_t *expression,
 987                                             type_t *expression_type);
 988
 989 static initializer_t *parse_sub_initializer_elem(type_t *type)
 990 {
 991         if(token.type == '{') {
 992                 return parse_sub_initializer(type, NULL, NULL);
 993         }
 994
 995         expression_t *expression      = parse_assignment_expression();
 996         type_t       *expression_type = skip_typeref(expression->base.datatype);
 997
 998         return parse_sub_initializer(type, expression, expression_type);
 999 }
1000
1001 static bool had_initializer_brace_warning;
1002
1003 static void skip_designator(void)
1004 {
1005         while(1) {
1006                 if(token.type == '.') {
1007                         next_token();
1008                         if(token.type == T_IDENTIFIER)
1009                                 next_token();
1010                 } else if(token.type == '[') {
1011                         next_token();
1012                         parse_constant_expression();
1013                         if(token.type == ']')
1014                                 next_token();
1015                 } else {
1016                         break;
1017                 }
1018         }
1019 }
1020
1021 static initializer_t *parse_sub_initializer(type_t *type,
1022                                             expression_t *expression,
1023                                             type_t *expression_type)
1024 {
1025         if(is_type_scalar(type)) {
1026                 /* there might be extra {} hierarchies */
1027                 if(token.type == '{') {
1028                         next_token();
1029                         if(!had_initializer_brace_warning) {
1030                                 warningf(HERE, "braces around scalar initializer");
1031                                 had_initializer_brace_warning = true;
1032                         }
1033                         initializer_t *result = parse_sub_initializer(type, NULL, NULL);
1034                         if(token.type == ',') {
1035                                 next_token();
1036                                 /* TODO: warn about excessive elements */
1037                         }
1038                         expect_block('}');
1039                         return result;
1040                 }
1041
1042                 if(expression == NULL) {
1043                         expression = parse_assignment_expression();
1044                 }
1045                 return initializer_from_expression(type, expression);
1046         }
1047
1048         /* does the expression match the currently looked at object to initialize */
1049         if(expression != NULL) {
1050                 initializer_t *result = initializer_from_expression(type, expression);
1051                 if(result != NULL)
1052                         return result;
1053         }
1054
1055         bool read_paren = false;
1056         if(token.type == '{') {
1057                 next_token();
1058                 read_paren = true;
1059         }
1060
1061         /* descend into subtype */
1062         initializer_t  *result = NULL;
1063         initializer_t **elems;
1064         if(is_type_array(type)) {
1065                 if(token.type == '.') {
1066                         errorf(HERE,
1067                                "compound designator in initializer for array type '%T'",
1068                                type);
1069                         skip_designator();
1070                 }
1071
1072                 type_t *const element_type = skip_typeref(type->array.element_type);
1073
1074                 initializer_t *sub;
1075                 had_initializer_brace_warning = false;
1076                 if(expression == NULL) {
1077                         sub = parse_sub_initializer_elem(element_type);
1078                 } else {
1079                         sub = parse_sub_initializer(element_type, expression,
1080                                                     expression_type);
1081                 }
1082
1083                 /* didn't match the subtypes -> try the parent type */
1084                 if(sub == NULL) {
1085                         assert(!read_paren);
1086                         return NULL;
1087                 }
1088
1089                 elems = NEW_ARR_F(initializer_t*, 0);
1090                 ARR_APP1(initializer_t*, elems, sub);
1091
1092                 while(true) {
1093                         if(token.type == '}')
1094                                 break;
1095                         expect_block(',');
1096                         if(token.type == '}')
1097                                 break;
1098
1099                         sub = parse_sub_initializer_elem(element_type);
1100                         if(sub == NULL) {
1101                                 /* TODO error, do nicer cleanup */
1102                                 errorf(HERE, "member initializer didn't match");
1103                                 DEL_ARR_F(elems);
1104                                 return NULL;
1105                         }
1106                         ARR_APP1(initializer_t*, elems, sub);
1107                 }
1108         } else {
1109                 assert(is_type_compound(type));
1110                 context_t *const context = &type->compound.declaration->context;
1111
1112                 if(token.type == '[') {
1113                         errorf(HERE,
1114                                "array designator in initializer for compound type '%T'",
1115                                type);
1116                         skip_designator();
1117                 }
1118
1119                 declaration_t *first = context->declarations;
1120                 if(first == NULL)
1121                         return NULL;
1122                 type_t *first_type = first->type;
1123                 first_type         = skip_typeref(first_type);
1124
1125                 initializer_t *sub;
1126                 had_initializer_brace_warning = false;
1127                 if(expression == NULL) {
1128                         sub = parse_sub_initializer_elem(first_type);
1129                 } else {
1130                         sub = parse_sub_initializer(first_type, expression,expression_type);
1131                 }
1132
1133                 /* didn't match the subtypes -> try our parent type */
1134                 if(sub == NULL) {
1135                         assert(!read_paren);
1136                         return NULL;
1137                 }
1138
1139                 elems = NEW_ARR_F(initializer_t*, 0);
1140                 ARR_APP1(initializer_t*, elems, sub);
1141
1142                 declaration_t *iter  = first->next;
1143                 for( ; iter != NULL; iter = iter->next) {
1144                         if(iter->symbol == NULL)
1145                                 continue;
1146                         if(iter->namespc != NAMESPACE_NORMAL)
1147                                 continue;
1148
1149                         if(token.type == '}')
1150                                 break;
1151                         expect_block(',');
1152                         if(token.type == '}')
1153                                 break;
1154
1155                         type_t *iter_type = iter->type;
1156                         iter_type         = skip_typeref(iter_type);
1157
1158                         sub = parse_sub_initializer_elem(iter_type);
1159                         if(sub == NULL) {
1160                                 /* TODO error, do nicer cleanup */
1161                                 errorf(HERE, "member initializer didn't match");
1162                                 DEL_ARR_F(elems);
1163                                 return NULL;
1164                         }
1165                         ARR_APP1(initializer_t*, elems, sub);
1166                 }
1167         }
1168
1169         int    len        = ARR_LEN(elems);
1170         size_t elems_size = sizeof(initializer_t*) * len;
1171
1172         initializer_list_t *init = allocate_ast_zero(sizeof(init[0]) + elems_size);
1173
1174         init->initializer.kind = INITIALIZER_LIST;
1175         init->len              = len;
1176         memcpy(init->initializers, elems, elems_size);
1177         DEL_ARR_F(elems);
1178
1179         result = (initializer_t*) init;
1180
1181         if(read_paren) {
1182                 if(token.type == ',')
1183                         next_token();
1184                 expect('}');
1185         }
1186         return result;
1187 }
1188
1189 static initializer_t *parse_initializer(type_t *const orig_type)
1190 {
1191         initializer_t *result;
1192
1193         type_t *const type = skip_typeref(orig_type);
1194
1195         if(token.type != '{') {
1196                 expression_t  *expression  = parse_assignment_expression();
1197                 initializer_t *initializer = initializer_from_expression(type, expression);
1198                 if(initializer == NULL) {
1199                         errorf(HERE,
1200                                 "initializer expression '%E' of type '%T' is incompatible with type '%T'",
1201                                 expression, expression->base.datatype, orig_type);
1202                 }
1203                 return initializer;
1204         }
1205
1206         if(is_type_scalar(type)) {
1207                 /* § 6.7.8.11 */
1208                 eat('{');
1209
1210                 expression_t *expression = parse_assignment_expression();
1211                 result = initializer_from_expression(type, expression);
1212
1213                 if(token.type == ',')
1214                         next_token();
1215
1216                 expect('}');
1217                 return result;
1218         } else {
1219                 result = parse_sub_initializer(type, NULL, NULL);
1220         }
1221
1222         return result;
1223 }
1224
1225 static declaration_t *append_declaration(declaration_t *declaration);
1226
1227 static declaration_t *parse_compound_type_specifier(bool is_struct)
1228 {
1229         if(is_struct) {
1230                 eat(T_struct);
1231         } else {
1232                 eat(T_union);
1233         }
1234
1235         symbol_t      *symbol      = NULL;
1236         declaration_t *declaration = NULL;
1237
1238         if (token.type == T___attribute__) {
1239                 /* TODO */
1240                 parse_attributes();
1241         }
1242
1243         if(token.type == T_IDENTIFIER) {
1244                 symbol = token.v.symbol;
1245                 next_token();
1246
1247                 if(is_struct) {
1248                         declaration = get_declaration(symbol, NAMESPACE_STRUCT);
1249                 } else {
1250                         declaration = get_declaration(symbol, NAMESPACE_UNION);
1251                 }
1252         } else if(token.type != '{') {
1253                 if(is_struct) {
1254                         parse_error_expected("while parsing struct type specifier",
1255                                              T_IDENTIFIER, '{', 0);
1256                 } else {
1257                         parse_error_expected("while parsing union type specifier",
1258                                              T_IDENTIFIER, '{', 0);
1259                 }
1260
1261                 return NULL;
1262         }
1263
1264         if(declaration == NULL) {
1265                 declaration = allocate_declaration_zero();
1266                 declaration->namespc         =
1267                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
1268                 declaration->source_position = token.source_position;
1269                 declaration->symbol          = symbol;
1270                 declaration->parent_context  = context;
1271                 if (symbol != NULL) {
1272                         environment_push(declaration);
1273                 }
1274                 append_declaration(declaration);
1275         }
1276
1277         if(token.type == '{') {
1278                 if(declaration->init.is_defined) {
1279                         assert(symbol != NULL);
1280                         errorf(HERE, "multiple definition of '%s %Y'",
1281                                is_struct ? "struct" : "union", symbol);
1282                         declaration->context.declarations = NULL;
1283                 }
1284                 declaration->init.is_defined = true;
1285
1286                 int         top          = environment_top();
1287                 context_t  *last_context = context;
1288                 set_context(&declaration->context);
1289
1290                 parse_compound_type_entries();
1291                 parse_attributes();
1292
1293                 assert(context == &declaration->context);
1294                 set_context(last_context);
1295                 environment_pop_to(top);
1296         }
1297
1298         return declaration;
1299 }
1300
1301 static void parse_enum_entries(type_t *const enum_type)
1302 {
1303         eat('{');
1304
1305         if(token.type == '}') {
1306                 next_token();
1307                 errorf(HERE, "empty enum not allowed");
1308                 return;
1309         }
1310
1311         do {
1312                 if(token.type != T_IDENTIFIER) {
1313                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, 0);
1314                         eat_block();
1315                         return;
1316                 }
1317
1318                 declaration_t *const entry = allocate_declaration_zero();
1319                 entry->storage_class   = STORAGE_CLASS_ENUM_ENTRY;
1320                 entry->type            = enum_type;
1321                 entry->symbol          = token.v.symbol;
1322                 entry->source_position = token.source_position;
1323                 next_token();
1324
1325                 if(token.type == '=') {
1326                         next_token();
1327                         entry->init.enum_value = parse_constant_expression();
1328
1329                         /* TODO semantic */
1330                 }
1331
1332                 record_declaration(entry);
1333
1334                 if(token.type != ',')
1335                         break;
1336                 next_token();
1337         } while(token.type != '}');
1338
1339         expect_void('}');
1340 }
1341
1342 static type_t *parse_enum_specifier(void)
1343 {
1344         eat(T_enum);
1345
1346         declaration_t *declaration;
1347         symbol_t      *symbol;
1348
1349         if(token.type == T_IDENTIFIER) {
1350                 symbol = token.v.symbol;
1351                 next_token();
1352
1353                 declaration = get_declaration(symbol, NAMESPACE_ENUM);
1354         } else if(token.type != '{') {
1355                 parse_error_expected("while parsing enum type specifier",
1356                                      T_IDENTIFIER, '{', 0);
1357                 return NULL;
1358         } else {
1359                 declaration = NULL;
1360                 symbol      = NULL;
1361         }
1362
1363         if(declaration == NULL) {
1364                 declaration = allocate_declaration_zero();
1365                 declaration->namespc         = NAMESPACE_ENUM;
1366                 declaration->source_position = token.source_position;
1367                 declaration->symbol          = symbol;
1368                 declaration->parent_context  = context;
1369         }
1370
1371         type_t *const type      = allocate_type_zero(TYPE_ENUM);
1372         type->enumt.declaration = declaration;
1373
1374         if(token.type == '{') {
1375                 if(declaration->init.is_defined) {
1376                         errorf(HERE, "multiple definitions of enum %Y", symbol);
1377                 }
1378                 if (symbol != NULL) {
1379                         environment_push(declaration);
1380                 }
1381                 append_declaration(declaration);
1382                 declaration->init.is_defined = 1;
1383
1384                 parse_enum_entries(type);
1385                 parse_attributes();
1386         }
1387
1388         return type;
1389 }
1390
1391 /**
1392  * if a symbol is a typedef to another type, return true
1393  */
1394 static bool is_typedef_symbol(symbol_t *symbol)
1395 {
1396         const declaration_t *const declaration =
1397                 get_declaration(symbol, NAMESPACE_NORMAL);
1398         return
1399                 declaration != NULL &&
1400                 declaration->storage_class == STORAGE_CLASS_TYPEDEF;
1401 }
1402
1403 static type_t *parse_typeof(void)
1404 {
1405         eat(T___typeof__);
1406
1407         type_t *type;
1408
1409         expect('(');
1410
1411         expression_t *expression  = NULL;
1412
1413 restart:
1414         switch(token.type) {
1415         case T___extension__:
1416                 /* this can be a prefix to a typename or an expression */
1417                 /* we simply eat it now. */
1418                 do {
1419                         next_token();
1420                 } while(token.type == T___extension__);
1421                 goto restart;
1422
1423         case T_IDENTIFIER:
1424                 if(is_typedef_symbol(token.v.symbol)) {
1425                         type = parse_typename();
1426                 } else {
1427                         expression = parse_expression();
1428                         type       = expression->base.datatype;
1429                 }
1430                 break;
1431
1432         TYPENAME_START
1433                 type = parse_typename();
1434                 break;
1435
1436         default:
1437                 expression = parse_expression();
1438                 type       = expression->base.datatype;
1439                 break;
1440         }
1441
1442         expect(')');
1443
1444         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF);
1445         typeof_type->typeoft.expression  = expression;
1446         typeof_type->typeoft.typeof_type = type;
1447
1448         return typeof_type;
1449 }
1450
1451 typedef enum {
1452         SPECIFIER_SIGNED    = 1 << 0,
1453         SPECIFIER_UNSIGNED  = 1 << 1,
1454         SPECIFIER_LONG      = 1 << 2,
1455         SPECIFIER_INT       = 1 << 3,
1456         SPECIFIER_DOUBLE    = 1 << 4,
1457         SPECIFIER_CHAR      = 1 << 5,
1458         SPECIFIER_SHORT     = 1 << 6,
1459         SPECIFIER_LONG_LONG = 1 << 7,
1460         SPECIFIER_FLOAT     = 1 << 8,
1461         SPECIFIER_BOOL      = 1 << 9,
1462         SPECIFIER_VOID      = 1 << 10,
1463 #ifdef PROVIDE_COMPLEX
1464         SPECIFIER_COMPLEX   = 1 << 11,
1465         SPECIFIER_IMAGINARY = 1 << 12,
1466 #endif
1467 } specifiers_t;
1468
1469 static type_t *create_builtin_type(symbol_t *const symbol,
1470                                    type_t *const real_type)
1471 {
1472         type_t *type            = allocate_type_zero(TYPE_BUILTIN);
1473         type->builtin.symbol    = symbol;
1474         type->builtin.real_type = real_type;
1475
1476         type_t *result = typehash_insert(type);
1477         if (type != result) {
1478                 free_type(type);
1479         }
1480
1481         return result;
1482 }
1483
1484 static type_t *get_typedef_type(symbol_t *symbol)
1485 {
1486         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
1487         if(declaration == NULL
1488                         || declaration->storage_class != STORAGE_CLASS_TYPEDEF)
1489                 return NULL;
1490
1491         type_t *type               = allocate_type_zero(TYPE_TYPEDEF);
1492         type->typedeft.declaration = declaration;
1493
1494         return type;
1495 }
1496
1497 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
1498 {
1499         type_t   *type            = NULL;
1500         unsigned  type_qualifiers = 0;
1501         unsigned  type_specifiers = 0;
1502         int       newtype         = 0;
1503
1504         specifiers->source_position = token.source_position;
1505
1506         while(true) {
1507                 switch(token.type) {
1508
1509                 /* storage class */
1510 #define MATCH_STORAGE_CLASS(token, class)                                \
1511                 case token:                                                      \
1512                         if(specifiers->storage_class != STORAGE_CLASS_NONE) {        \
1513                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
1514                         }                                                            \
1515                         specifiers->storage_class = class;                           \
1516                         next_token();                                                \
1517                         break;
1518
1519                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
1520                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
1521                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
1522                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
1523                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
1524
1525                 case T___thread:
1526                         switch (specifiers->storage_class) {
1527                                 case STORAGE_CLASS_NONE:
1528                                         specifiers->storage_class = STORAGE_CLASS_THREAD;
1529                                         break;
1530
1531                                 case STORAGE_CLASS_EXTERN:
1532                                         specifiers->storage_class = STORAGE_CLASS_THREAD_EXTERN;
1533                                         break;
1534
1535                                 case STORAGE_CLASS_STATIC:
1536                                         specifiers->storage_class = STORAGE_CLASS_THREAD_STATIC;
1537                                         break;
1538
1539                                 default:
1540                                         errorf(HERE, "multiple storage classes in declaration specifiers");
1541                                         break;
1542                         }
1543                         next_token();
1544                         break;
1545
1546                 /* type qualifiers */
1547 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
1548                 case token:                                                     \
1549                         type_qualifiers |= qualifier;                               \
1550                         next_token();                                               \
1551                         break;
1552
1553                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
1554                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
1555                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
1556
1557                 case T___extension__:
1558                         /* TODO */
1559                         next_token();
1560                         break;
1561
1562                 /* type specifiers */
1563 #define MATCH_SPECIFIER(token, specifier, name)                         \
1564                 case token:                                                     \
1565                         next_token();                                               \
1566                         if(type_specifiers & specifier) {                           \
1567                                 errorf(HERE, "multiple " name " type specifiers given"); \
1568                         } else {                                                    \
1569                                 type_specifiers |= specifier;                           \
1570                         }                                                           \
1571                         break;
1572
1573                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void")
1574                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char")
1575                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short")
1576                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int")
1577                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float")
1578                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double")
1579                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed")
1580                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned")
1581                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool")
1582 #ifdef PROVIDE_COMPLEX
1583                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex")
1584                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary")
1585 #endif
1586                 case T_forceinline:
1587                         /* only in microsoft mode */
1588                         specifiers->decl_modifiers |= DM_FORCEINLINE;
1589
1590                 case T_inline:
1591                         next_token();
1592                         specifiers->is_inline = true;
1593                         break;
1594
1595                 case T_long:
1596                         next_token();
1597                         if(type_specifiers & SPECIFIER_LONG_LONG) {
1598                                 errorf(HERE, "multiple type specifiers given");
1599                         } else if(type_specifiers & SPECIFIER_LONG) {
1600                                 type_specifiers |= SPECIFIER_LONG_LONG;
1601                         } else {
1602                                 type_specifiers |= SPECIFIER_LONG;
1603                         }
1604                         break;
1605
1606                 /* TODO: if is_type_valid(type) for the following rules should issue
1607                  * an error */
1608                 case T_struct: {
1609                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
1610
1611                         type->compound.declaration = parse_compound_type_specifier(true);
1612                         break;
1613                 }
1614                 case T_union: {
1615                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
1616
1617                         type->compound.declaration = parse_compound_type_specifier(false);
1618                         break;
1619                 }
1620                 case T_enum:
1621                         type = parse_enum_specifier();
1622                         break;
1623                 case T___typeof__:
1624                         type = parse_typeof();
1625                         break;
1626                 case T___builtin_va_list:
1627                         type = duplicate_type(type_valist);
1628                         next_token();
1629                         break;
1630
1631                 case T___attribute__:
1632                         /* TODO */
1633                         parse_attributes();
1634                         break;
1635
1636                 case T_IDENTIFIER: {
1637                         type_t *typedef_type = get_typedef_type(token.v.symbol);
1638
1639                         if(typedef_type == NULL)
1640                                 goto finish_specifiers;
1641
1642                         next_token();
1643                         type = typedef_type;
1644                         break;
1645                 }
1646
1647                 /* function specifier */
1648                 default:
1649                         goto finish_specifiers;
1650                 }
1651         }
1652
1653 finish_specifiers:
1654
1655         if(type == NULL) {
1656                 atomic_type_kind_t atomic_type;
1657
1658                 /* match valid basic types */
1659                 switch(type_specifiers) {
1660                 case SPECIFIER_VOID:
1661                         atomic_type = ATOMIC_TYPE_VOID;
1662                         break;
1663                 case SPECIFIER_CHAR:
1664                         atomic_type = ATOMIC_TYPE_CHAR;
1665                         break;
1666                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
1667                         atomic_type = ATOMIC_TYPE_SCHAR;
1668                         break;
1669                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
1670                         atomic_type = ATOMIC_TYPE_UCHAR;
1671                         break;
1672                 case SPECIFIER_SHORT:
1673                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
1674                 case SPECIFIER_SHORT | SPECIFIER_INT:
1675                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
1676                         atomic_type = ATOMIC_TYPE_SHORT;
1677                         break;
1678                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
1679                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
1680                         atomic_type = ATOMIC_TYPE_USHORT;
1681                         break;
1682                 case SPECIFIER_INT:
1683                 case SPECIFIER_SIGNED:
1684                 case SPECIFIER_SIGNED | SPECIFIER_INT:
1685                         atomic_type = ATOMIC_TYPE_INT;
1686                         break;
1687                 case SPECIFIER_UNSIGNED:
1688                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
1689                         atomic_type = ATOMIC_TYPE_UINT;
1690                         break;
1691                 case SPECIFIER_LONG:
1692                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
1693                 case SPECIFIER_LONG | SPECIFIER_INT:
1694                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
1695                         atomic_type = ATOMIC_TYPE_LONG;
1696                         break;
1697                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
1698                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
1699                         atomic_type = ATOMIC_TYPE_ULONG;
1700                         break;
1701                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
1702                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
1703                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
1704                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
1705                         | SPECIFIER_INT:
1706                         atomic_type = ATOMIC_TYPE_LONGLONG;
1707                         break;
1708                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
1709                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
1710                         | SPECIFIER_INT:
1711                         atomic_type = ATOMIC_TYPE_ULONGLONG;
1712                         break;
1713                 case SPECIFIER_FLOAT:
1714                         atomic_type = ATOMIC_TYPE_FLOAT;
1715                         break;
1716                 case SPECIFIER_DOUBLE:
1717                         atomic_type = ATOMIC_TYPE_DOUBLE;
1718                         break;
1719                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
1720                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
1721                         break;
1722                 case SPECIFIER_BOOL:
1723                         atomic_type = ATOMIC_TYPE_BOOL;
1724                         break;
1725 #ifdef PROVIDE_COMPLEX
1726                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
1727                         atomic_type = ATOMIC_TYPE_FLOAT_COMPLEX;
1728                         break;
1729                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
1730                         atomic_type = ATOMIC_TYPE_DOUBLE_COMPLEX;
1731                         break;
1732                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
1733                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE_COMPLEX;
1734                         break;
1735                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
1736                         atomic_type = ATOMIC_TYPE_FLOAT_IMAGINARY;
1737                         break;
1738                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
1739                         atomic_type = ATOMIC_TYPE_DOUBLE_IMAGINARY;
1740                         break;
1741                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
1742                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE_IMAGINARY;
1743                         break;
1744 #endif
1745                 default:
1746                         /* invalid specifier combination, give an error message */
1747                         if(type_specifiers == 0) {
1748                                 if (! strict_mode) {
1749                                         if (warning.implicit_int) {
1750                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
1751                                         }
1752                                         atomic_type = ATOMIC_TYPE_INT;
1753                                         break;
1754                                 } else {
1755                                         errorf(HERE, "no type specifiers given in declaration");
1756                                 }
1757                         } else if((type_specifiers & SPECIFIER_SIGNED) &&
1758                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
1759                                 errorf(HERE, "signed and unsigned specifiers gives");
1760                         } else if(type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
1761                                 errorf(HERE, "only integer types can be signed or unsigned");
1762                         } else {
1763                                 errorf(HERE, "multiple datatypes in declaration");
1764                         }
1765                         atomic_type = ATOMIC_TYPE_INVALID;
1766                 }
1767
1768                 type               = allocate_type_zero(TYPE_ATOMIC);
1769                 type->atomic.akind = atomic_type;
1770                 newtype            = 1;
1771         } else {
1772                 if(type_specifiers != 0) {
1773                         errorf(HERE, "multiple datatypes in declaration");
1774                 }
1775         }
1776
1777         type->base.qualifiers = type_qualifiers;
1778
1779         type_t *result = typehash_insert(type);
1780         if(newtype && result != type) {
1781                 free_type(type);
1782         }
1783
1784         specifiers->type = result;
1785 }
1786
1787 static type_qualifiers_t parse_type_qualifiers(void)
1788 {
1789         type_qualifiers_t type_qualifiers = TYPE_QUALIFIER_NONE;
1790
1791         while(true) {
1792                 switch(token.type) {
1793                 /* type qualifiers */
1794                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
1795                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
1796                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
1797
1798                 default:
1799                         return type_qualifiers;
1800                 }
1801         }
1802 }
1803
1804 static declaration_t *parse_identifier_list(void)
1805 {
1806         declaration_t *declarations     = NULL;
1807         declaration_t *last_declaration = NULL;
1808         do {
1809                 declaration_t *const declaration = allocate_declaration_zero();
1810                 declaration->source_position = token.source_position;
1811                 declaration->symbol          = token.v.symbol;
1812                 next_token();
1813
1814                 if(last_declaration != NULL) {
1815                         last_declaration->next = declaration;
1816                 } else {
1817                         declarations = declaration;
1818                 }
1819                 last_declaration = declaration;
1820
1821                 if(token.type != ',')
1822                         break;
1823                 next_token();
1824         } while(token.type == T_IDENTIFIER);
1825
1826         return declarations;
1827 }
1828
1829 static void semantic_parameter(declaration_t *declaration)
1830 {
1831         /* TODO: improve error messages */
1832
1833         if(declaration->storage_class == STORAGE_CLASS_TYPEDEF) {
1834                 errorf(HERE, "typedef not allowed in parameter list");
1835         } else if(declaration->storage_class != STORAGE_CLASS_NONE
1836                         && declaration->storage_class != STORAGE_CLASS_REGISTER) {
1837                 errorf(HERE, "parameter may only have none or register storage class");
1838         }
1839
1840         type_t *const orig_type = declaration->type;
1841         type_t *      type      = skip_typeref(orig_type);
1842
1843         /* Array as last part of a parameter type is just syntactic sugar.  Turn it
1844          * into a pointer. § 6.7.5.3 (7) */
1845         if (is_type_array(type)) {
1846                 type_t *const element_type = type->array.element_type;
1847
1848                 type = make_pointer_type(element_type, type->base.qualifiers);
1849
1850                 declaration->type = type;
1851         }
1852
1853         if(is_type_incomplete(type)) {
1854                 errorf(HERE, "incomplete type ('%T') not allowed for parameter '%Y'",
1855                        orig_type, declaration->symbol);
1856         }
1857 }
1858
1859 static declaration_t *parse_parameter(void)
1860 {
1861         declaration_specifiers_t specifiers;
1862         memset(&specifiers, 0, sizeof(specifiers));
1863
1864         parse_declaration_specifiers(&specifiers);
1865
1866         declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/true);
1867
1868         semantic_parameter(declaration);
1869
1870         return declaration;
1871 }
1872
1873 static declaration_t *parse_parameters(function_type_t *type)
1874 {
1875         if(token.type == T_IDENTIFIER) {
1876                 symbol_t *symbol = token.v.symbol;
1877                 if(!is_typedef_symbol(symbol)) {
1878                         type->kr_style_parameters = true;
1879                         return parse_identifier_list();
1880                 }
1881         }
1882
1883         if(token.type == ')') {
1884                 type->unspecified_parameters = 1;
1885                 return NULL;
1886         }
1887         if(token.type == T_void && look_ahead(1)->type == ')') {
1888                 next_token();
1889                 return NULL;
1890         }
1891
1892         declaration_t        *declarations = NULL;
1893         declaration_t        *declaration;
1894         declaration_t        *last_declaration = NULL;
1895         function_parameter_t *parameter;
1896         function_parameter_t *last_parameter = NULL;
1897
1898         while(true) {
1899                 switch(token.type) {
1900                 case T_DOTDOTDOT:
1901                         next_token();
1902                         type->variadic = 1;
1903                         return declarations;
1904
1905                 case T_IDENTIFIER:
1906                 case T___extension__:
1907                 DECLARATION_START
1908                         declaration = parse_parameter();
1909
1910                         parameter       = obstack_alloc(type_obst, sizeof(parameter[0]));
1911                         memset(parameter, 0, sizeof(parameter[0]));
1912                         parameter->type = declaration->type;
1913
1914                         if(last_parameter != NULL) {
1915                                 last_declaration->next = declaration;
1916                                 last_parameter->next   = parameter;
1917                         } else {
1918                                 type->parameters = parameter;
1919                                 declarations     = declaration;
1920                         }
1921                         last_parameter   = parameter;
1922                         last_declaration = declaration;
1923                         break;
1924
1925                 default:
1926                         return declarations;
1927                 }
1928                 if(token.type != ',')
1929                         return declarations;
1930                 next_token();
1931         }
1932 }
1933
1934 typedef enum {
1935         CONSTRUCT_INVALID,
1936         CONSTRUCT_POINTER,
1937         CONSTRUCT_FUNCTION,
1938         CONSTRUCT_ARRAY
1939 } construct_type_type_t;
1940
1941 typedef struct construct_type_t construct_type_t;
1942 struct construct_type_t {
1943         construct_type_type_t  type;
1944         construct_type_t      *next;
1945 };
1946
1947 typedef struct parsed_pointer_t parsed_pointer_t;
1948 struct parsed_pointer_t {
1949         construct_type_t  construct_type;
1950         type_qualifiers_t type_qualifiers;
1951 };
1952
1953 typedef struct construct_function_type_t construct_function_type_t;
1954 struct construct_function_type_t {
1955         construct_type_t  construct_type;
1956         type_t           *function_type;
1957 };
1958
1959 typedef struct parsed_array_t parsed_array_t;
1960 struct parsed_array_t {
1961         construct_type_t  construct_type;
1962         type_qualifiers_t type_qualifiers;
1963         bool              is_static;
1964         bool              is_variable;
1965         expression_t     *size;
1966 };
1967
1968 typedef struct construct_base_type_t construct_base_type_t;
1969 struct construct_base_type_t {
1970         construct_type_t  construct_type;
1971         type_t           *type;
1972 };
1973
1974 static construct_type_t *parse_pointer_declarator(void)
1975 {
1976         eat('*');
1977
1978         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
1979         memset(pointer, 0, sizeof(pointer[0]));
1980         pointer->construct_type.type = CONSTRUCT_POINTER;
1981         pointer->type_qualifiers     = parse_type_qualifiers();
1982
1983         return (construct_type_t*) pointer;
1984 }
1985
1986 static construct_type_t *parse_array_declarator(void)
1987 {
1988         eat('[');
1989
1990         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
1991         memset(array, 0, sizeof(array[0]));
1992         array->construct_type.type = CONSTRUCT_ARRAY;
1993
1994         if(token.type == T_static) {
1995                 array->is_static = true;
1996                 next_token();
1997         }
1998
1999         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
2000         if(type_qualifiers != 0) {
2001                 if(token.type == T_static) {
2002                         array->is_static = true;
2003                         next_token();
2004                 }
2005         }
2006         array->type_qualifiers = type_qualifiers;
2007
2008         if(token.type == '*' && look_ahead(1)->type == ']') {
2009                 array->is_variable = true;
2010                 next_token();
2011         } else if(token.type != ']') {
2012                 array->size = parse_assignment_expression();
2013         }
2014
2015         expect(']');
2016
2017         return (construct_type_t*) array;
2018 }
2019
2020 static construct_type_t *parse_function_declarator(declaration_t *declaration)
2021 {
2022         eat('(');
2023
2024         type_t *type = allocate_type_zero(TYPE_FUNCTION);
2025
2026         declaration_t *parameters = parse_parameters(&type->function);
2027         if(declaration != NULL) {
2028                 declaration->context.declarations = parameters;
2029         }
2030
2031         construct_function_type_t *construct_function_type =
2032                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
2033         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
2034         construct_function_type->construct_type.type = CONSTRUCT_FUNCTION;
2035         construct_function_type->function_type       = type;
2036
2037         expect(')');
2038
2039         return (construct_type_t*) construct_function_type;
2040 }
2041
2042 static construct_type_t *parse_inner_declarator(declaration_t *declaration,
2043                 bool may_be_abstract)
2044 {
2045         /* construct a single linked list of construct_type_t's which describe
2046          * how to construct the final declarator type */
2047         construct_type_t *first = NULL;
2048         construct_type_t *last  = NULL;
2049
2050         /* pointers */
2051         while(token.type == '*') {
2052                 construct_type_t *type = parse_pointer_declarator();
2053
2054                 if(last == NULL) {
2055                         first = type;
2056                         last  = type;
2057                 } else {
2058                         last->next = type;
2059                         last       = type;
2060                 }
2061         }
2062
2063         /* TODO: find out if this is correct */
2064         parse_attributes();
2065
2066         construct_type_t *inner_types = NULL;
2067
2068         switch(token.type) {
2069         case T_IDENTIFIER:
2070                 if(declaration == NULL) {
2071                         errorf(HERE, "no identifier expected in typename");
2072                 } else {
2073                         declaration->symbol          = token.v.symbol;
2074                         declaration->source_position = token.source_position;
2075                 }
2076                 next_token();
2077                 break;
2078         case '(':
2079                 next_token();
2080                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
2081                 expect(')');
2082                 break;
2083         default:
2084                 if(may_be_abstract)
2085                         break;
2086                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', 0);
2087                 /* avoid a loop in the outermost scope, because eat_statement doesn't
2088                  * eat '}' */
2089                 if(token.type == '}' && current_function == NULL) {
2090                         next_token();
2091                 } else {
2092                         eat_statement();
2093                 }
2094                 return NULL;
2095         }
2096
2097         construct_type_t *p = last;
2098
2099         while(true) {
2100                 construct_type_t *type;
2101                 switch(token.type) {
2102                 case '(':
2103                         type = parse_function_declarator(declaration);
2104                         break;
2105                 case '[':
2106                         type = parse_array_declarator();
2107                         break;
2108                 default:
2109                         goto declarator_finished;
2110                 }
2111
2112                 /* insert in the middle of the list (behind p) */
2113                 if(p != NULL) {
2114                         type->next = p->next;
2115                         p->next    = type;
2116                 } else {
2117                         type->next = first;
2118                         first      = type;
2119                 }
2120                 if(last == p) {
2121                         last = type;
2122                 }
2123         }
2124
2125 declarator_finished:
2126         parse_attributes();
2127
2128         /* append inner_types at the end of the list, we don't to set last anymore
2129          * as it's not needed anymore */
2130         if(last == NULL) {
2131                 assert(first == NULL);
2132                 first = inner_types;
2133         } else {
2134                 last->next = inner_types;
2135         }
2136
2137         return first;
2138 }
2139
2140 static type_t *construct_declarator_type(construct_type_t *construct_list,
2141                                          type_t *type)
2142 {
2143         construct_type_t *iter = construct_list;
2144         for( ; iter != NULL; iter = iter->next) {
2145                 switch(iter->type) {
2146                 case CONSTRUCT_INVALID:
2147                         panic("invalid type construction found");
2148                 case CONSTRUCT_FUNCTION: {
2149                         construct_function_type_t *construct_function_type
2150                                 = (construct_function_type_t*) iter;
2151
2152                         type_t *function_type = construct_function_type->function_type;
2153
2154                         function_type->function.return_type = type;
2155
2156                         type_t *skipped_return_type = skip_typeref(type);
2157                         if (is_type_function(skipped_return_type)) {
2158                                 errorf(HERE, "function returning function is not allowed");
2159                                 type = type_error_type;
2160                         } else if (is_type_array(skipped_return_type)) {
2161                                 errorf(HERE, "function returning array is not allowed");
2162                                 type = type_error_type;
2163                         } else {
2164                                 type = function_type;
2165                         }
2166                         break;
2167                 }
2168
2169                 case CONSTRUCT_POINTER: {
2170                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
2171                         type_t           *pointer_type   = allocate_type_zero(TYPE_POINTER);
2172                         pointer_type->pointer.points_to  = type;
2173                         pointer_type->base.qualifiers    = parsed_pointer->type_qualifiers;
2174
2175                         type = pointer_type;
2176                         break;
2177                 }
2178
2179                 case CONSTRUCT_ARRAY: {
2180                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
2181                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY);
2182
2183                         array_type->base.qualifiers    = parsed_array->type_qualifiers;
2184                         array_type->array.element_type = type;
2185                         array_type->array.is_static    = parsed_array->is_static;
2186                         array_type->array.is_variable  = parsed_array->is_variable;
2187                         array_type->array.size         = parsed_array->size;
2188
2189                         type_t *skipped_type = skip_typeref(type);
2190                         if (is_type_atomic(skipped_type, ATOMIC_TYPE_VOID)) {
2191                                 errorf(HERE, "array of void is not allowed");
2192                                 type = type_error_type;
2193                         } else {
2194                                 type = array_type;
2195                         }
2196                         break;
2197                 }
2198                 }
2199
2200                 type_t *hashed_type = typehash_insert(type);
2201                 if(hashed_type != type) {
2202                         /* the function type was constructed earlier freeing it here will
2203                          * destroy other types... */
2204                         if(iter->type != CONSTRUCT_FUNCTION) {
2205                                 free_type(type);
2206                         }
2207                         type = hashed_type;
2208                 }
2209         }
2210
2211         return type;
2212 }
2213
2214 static declaration_t *parse_declarator(
2215                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
2216 {
2217         declaration_t *const declaration = allocate_declaration_zero();
2218         declaration->storage_class  = specifiers->storage_class;
2219         declaration->modifiers      = specifiers->decl_modifiers;
2220         declaration->is_inline      = specifiers->is_inline;
2221
2222         construct_type_t *construct_type
2223                 = parse_inner_declarator(declaration, may_be_abstract);
2224         type_t *const type = specifiers->type;
2225         declaration->type = construct_declarator_type(construct_type, type);
2226
2227         if(construct_type != NULL) {
2228                 obstack_free(&temp_obst, construct_type);
2229         }
2230
2231         return declaration;
2232 }
2233
2234 static type_t *parse_abstract_declarator(type_t *base_type)
2235 {
2236         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
2237
2238         type_t *result = construct_declarator_type(construct_type, base_type);
2239         if(construct_type != NULL) {
2240                 obstack_free(&temp_obst, construct_type);
2241         }
2242
2243         return result;
2244 }
2245
2246 static declaration_t *append_declaration(declaration_t* const declaration)
2247 {
2248         if (last_declaration != NULL) {
2249                 last_declaration->next = declaration;
2250         } else {
2251                 context->declarations = declaration;
2252         }
2253         last_declaration = declaration;
2254         return declaration;
2255 }
2256
2257 static declaration_t *internal_record_declaration(
2258         declaration_t *const declaration,
2259         const bool is_function_definition)
2260 {
2261         const symbol_t *const symbol  = declaration->symbol;
2262         const namespace_t     namespc = (namespace_t)declaration->namespc;
2263
2264         const type_t *const type = skip_typeref(declaration->type);
2265         if (is_type_function(type) &&
2266                         type->function.unspecified_parameters &&
2267                         warning.strict_prototypes) {
2268                 warningf(declaration->source_position,
2269                          "function declaration '%#T' is not a prototype",
2270                          type, declaration->symbol);
2271         }
2272
2273         declaration_t *const previous_declaration = get_declaration(symbol, namespc);
2274         assert(declaration != previous_declaration);
2275         if (previous_declaration != NULL) {
2276                 if (previous_declaration->parent_context == context) {
2277                         /* can happen for K&R style declarations */
2278                         if(previous_declaration->type == NULL) {
2279                                 previous_declaration->type = declaration->type;
2280                         }
2281
2282                         const type_t *const prev_type = skip_typeref(previous_declaration->type);
2283                         if (!types_compatible(type, prev_type)) {
2284                                 errorf(declaration->source_position,
2285                                         "declaration '%#T' is incompatible with previous declaration '%#T'",
2286                                         type, symbol, previous_declaration->type, symbol);
2287                                 errorf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol);
2288                         } else {
2289                                 unsigned old_storage_class = previous_declaration->storage_class;
2290                                 unsigned new_storage_class = declaration->storage_class;
2291
2292                                 /* pretend no storage class means extern for function declarations
2293                                  * (except if the previous declaration is neither none nor extern) */
2294                                 if (is_type_function(type)) {
2295                                         switch (old_storage_class) {
2296                                                 case STORAGE_CLASS_NONE:
2297                                                         old_storage_class = STORAGE_CLASS_EXTERN;
2298
2299                                                 case STORAGE_CLASS_EXTERN:
2300                                                         if (new_storage_class == STORAGE_CLASS_NONE && !is_function_definition) {
2301                                                                 new_storage_class = STORAGE_CLASS_EXTERN;
2302                                                         }
2303                                                         break;
2304
2305                                                 default: break;
2306                                         }
2307                                 }
2308
2309                                 if (old_storage_class == STORAGE_CLASS_EXTERN &&
2310                                                 new_storage_class == STORAGE_CLASS_EXTERN) {
2311         warn_redundant_declaration:
2312                                         if (warning.redundant_decls) {
2313                                                 warningf(declaration->source_position, "redundant declaration for '%Y'", symbol);
2314                                                 warningf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol);
2315                                         }
2316                                 } else if (current_function == NULL) {
2317                                         if (old_storage_class != STORAGE_CLASS_STATIC &&
2318                                                         new_storage_class == STORAGE_CLASS_STATIC) {
2319                                                 errorf(declaration->source_position, "static declaration of '%Y' follows non-static declaration", symbol);
2320                                                 errorf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol);
2321                                         } else {
2322                                                 if (old_storage_class != STORAGE_CLASS_EXTERN && !is_function_definition) {
2323                                                         goto warn_redundant_declaration;
2324                                                 }
2325                                                 if (new_storage_class == STORAGE_CLASS_NONE) {
2326                                                         previous_declaration->storage_class = STORAGE_CLASS_NONE;
2327                                                 }
2328                                         }
2329                                 } else {
2330                                         if (old_storage_class == new_storage_class) {
2331                                                 errorf(declaration->source_position, "redeclaration of '%Y'", symbol);
2332                                         } else {
2333                                                 errorf(declaration->source_position, "redeclaration of '%Y' with different linkage", symbol);
2334                                         }
2335                                         errorf(previous_declaration->source_position, "previous declaration of '%Y' was here", symbol);
2336                                 }
2337                         }
2338                         return previous_declaration;
2339                 }
2340         } else if (is_function_definition &&
2341                         declaration->storage_class != STORAGE_CLASS_STATIC &&
2342                         warning.missing_declarations) {
2343                 warningf(declaration->source_position, "no previous declaration for '%#T'", type, symbol);
2344         }
2345
2346         assert(declaration->parent_context == NULL);
2347         assert(declaration->symbol != NULL);
2348         assert(context != NULL);
2349
2350         declaration->parent_context = context;
2351
2352         environment_push(declaration);
2353         return append_declaration(declaration);
2354 }
2355
2356 static declaration_t *record_declaration(declaration_t *declaration)
2357 {
2358         return internal_record_declaration(declaration, false);
2359 }
2360
2361 static declaration_t *record_function_definition(declaration_t *declaration)
2362 {
2363         return internal_record_declaration(declaration, true);
2364 }
2365
2366 static void parser_error_multiple_definition(declaration_t *declaration,
2367                 const source_position_t source_position)
2368 {
2369         errorf(source_position, "multiple definition of symbol '%Y'",
2370                declaration->symbol);
2371         errorf(declaration->source_position,
2372                "this is the location of the previous definition.");
2373 }
2374
2375 static bool is_declaration_specifier(const token_t *token,
2376                                      bool only_type_specifiers)
2377 {
2378         switch(token->type) {
2379                 TYPE_SPECIFIERS
2380                         return true;
2381                 case T_IDENTIFIER:
2382                         return is_typedef_symbol(token->v.symbol);
2383
2384                 case T___extension__:
2385                 STORAGE_CLASSES
2386                 TYPE_QUALIFIERS
2387                         return !only_type_specifiers;
2388
2389                 default:
2390                         return false;
2391         }
2392 }
2393
2394 static void parse_init_declarator_rest(declaration_t *declaration)
2395 {
2396         eat('=');
2397
2398         type_t *orig_type = declaration->type;
2399         type_t *type      = type = skip_typeref(orig_type);
2400
2401         if(declaration->init.initializer != NULL) {
2402                 parser_error_multiple_definition(declaration, token.source_position);
2403         }
2404
2405         initializer_t *initializer = parse_initializer(type);
2406
2407         /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
2408          * the array type size */
2409         if(is_type_array(type) && initializer != NULL) {
2410                 array_type_t *array_type = &type->array;
2411
2412                 if(array_type->size == NULL) {
2413                         expression_t *cnst = allocate_expression_zero(EXPR_CONST);
2414
2415                         cnst->base.datatype = type_size_t;
2416
2417                         switch (initializer->kind) {
2418                                 case INITIALIZER_LIST: {
2419                                         cnst->conste.v.int_value = initializer->list.len;
2420                                         break;
2421                                 }
2422
2423                                 case INITIALIZER_STRING: {
2424                                         cnst->conste.v.int_value = initializer->string.string.size;
2425                                         break;
2426                                 }
2427
2428                                 case INITIALIZER_WIDE_STRING: {
2429                                         cnst->conste.v.int_value = initializer->wide_string.string.size;
2430                                         break;
2431                                 }
2432
2433                                 default:
2434                                         panic("invalid initializer type");
2435                         }
2436
2437                         array_type->size = cnst;
2438                 }
2439         }
2440
2441         if(is_type_function(type)) {
2442                 errorf(declaration->source_position,
2443                        "initializers not allowed for function types at declator '%Y' (type '%T')",
2444                        declaration->symbol, orig_type);
2445         } else {
2446                 declaration->init.initializer = initializer;
2447         }
2448 }
2449
2450 /* parse rest of a declaration without any declarator */
2451 static void parse_anonymous_declaration_rest(
2452                 const declaration_specifiers_t *specifiers,
2453                 parsed_declaration_func finished_declaration)
2454 {
2455         eat(';');
2456
2457         declaration_t *const declaration = allocate_declaration_zero();
2458         declaration->type            = specifiers->type;
2459         declaration->storage_class   = specifiers->storage_class;
2460         declaration->source_position = specifiers->source_position;
2461
2462         if (declaration->storage_class != STORAGE_CLASS_NONE) {
2463                 warningf(declaration->source_position, "useless storage class in empty declaration");
2464         }
2465
2466         type_t *type = declaration->type;
2467         switch (type->kind) {
2468                 case TYPE_COMPOUND_STRUCT:
2469                 case TYPE_COMPOUND_UNION: {
2470                         if (type->compound.declaration->symbol == NULL) {
2471                                 warningf(declaration->source_position, "unnamed struct/union that defines no instances");
2472                         }
2473                         break;
2474                 }
2475
2476                 case TYPE_ENUM:
2477                         break;
2478
2479                 default:
2480                         warningf(declaration->source_position, "empty declaration");
2481                         break;
2482         }
2483
2484         finished_declaration(declaration);
2485 }
2486
2487 static void parse_declaration_rest(declaration_t *ndeclaration,
2488                 const declaration_specifiers_t *specifiers,
2489                 parsed_declaration_func finished_declaration)
2490 {
2491         while(true) {
2492                 declaration_t *declaration = finished_declaration(ndeclaration);
2493
2494                 type_t *orig_type = declaration->type;
2495                 type_t *type      = skip_typeref(orig_type);
2496
2497                 if (type->kind != TYPE_FUNCTION &&
2498                     declaration->is_inline &&
2499                     is_type_valid(type)) {
2500                         warningf(declaration->source_position,
2501                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
2502                 }
2503
2504                 if(token.type == '=') {
2505                         parse_init_declarator_rest(declaration);
2506                 }
2507
2508                 if(token.type != ',')
2509                         break;
2510                 eat(',');
2511
2512                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
2513         }
2514         expect_void(';');
2515 }
2516
2517 static declaration_t *finished_kr_declaration(declaration_t *declaration)
2518 {
2519         symbol_t *symbol  = declaration->symbol;
2520         if(symbol == NULL) {
2521                 errorf(HERE, "anonymous declaration not valid as function parameter");
2522                 return declaration;
2523         }
2524         namespace_t namespc = (namespace_t) declaration->namespc;
2525         if(namespc != NAMESPACE_NORMAL) {
2526                 return record_declaration(declaration);
2527         }
2528
2529         declaration_t *previous_declaration = get_declaration(symbol, namespc);
2530         if(previous_declaration == NULL ||
2531                         previous_declaration->parent_context != context) {
2532                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
2533                        symbol);
2534                 return declaration;
2535         }
2536
2537         if(previous_declaration->type == NULL) {
2538                 previous_declaration->type           = declaration->type;
2539                 previous_declaration->storage_class  = declaration->storage_class;
2540                 previous_declaration->parent_context = context;
2541                 return previous_declaration;
2542         } else {
2543                 return record_declaration(declaration);
2544         }
2545 }
2546
2547 static void parse_declaration(parsed_declaration_func finished_declaration)
2548 {
2549         declaration_specifiers_t specifiers;
2550         memset(&specifiers, 0, sizeof(specifiers));
2551         parse_declaration_specifiers(&specifiers);
2552
2553         if(token.type == ';') {
2554                 parse_anonymous_declaration_rest(&specifiers, finished_declaration);
2555         } else {
2556                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
2557                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
2558         }
2559 }
2560
2561 static void parse_kr_declaration_list(declaration_t *declaration)
2562 {
2563         type_t *type = skip_typeref(declaration->type);
2564         if(!is_type_function(type))
2565                 return;
2566
2567         if(!type->function.kr_style_parameters)
2568                 return;
2569
2570         /* push function parameters */
2571         int         top          = environment_top();
2572         context_t  *last_context = context;
2573         set_context(&declaration->context);
2574
2575         declaration_t *parameter = declaration->context.declarations;
2576         for( ; parameter != NULL; parameter = parameter->next) {
2577                 assert(parameter->parent_context == NULL);
2578                 parameter->parent_context = context;
2579                 environment_push(parameter);
2580         }
2581
2582         /* parse declaration list */
2583         while(is_declaration_specifier(&token, false)) {
2584                 parse_declaration(finished_kr_declaration);
2585         }
2586
2587         /* pop function parameters */
2588         assert(context == &declaration->context);
2589         set_context(last_context);
2590         environment_pop_to(top);
2591
2592         /* update function type */
2593         type_t *new_type = duplicate_type(type);
2594         new_type->function.kr_style_parameters = false;
2595
2596         function_parameter_t *parameters     = NULL;
2597         function_parameter_t *last_parameter = NULL;
2598
2599         declaration_t *parameter_declaration = declaration->context.declarations;
2600         for( ; parameter_declaration != NULL;
2601                         parameter_declaration = parameter_declaration->next) {
2602                 type_t *parameter_type = parameter_declaration->type;
2603                 if(parameter_type == NULL) {
2604                         if (strict_mode) {
2605                                 errorf(HERE, "no type specified for function parameter '%Y'",
2606                                        parameter_declaration->symbol);
2607                         } else {
2608                                 if (warning.implicit_int) {
2609                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
2610                                                 parameter_declaration->symbol);
2611                                 }
2612                                 parameter_type              = type_int;
2613                                 parameter_declaration->type = parameter_type;
2614                         }
2615                 }
2616
2617                 semantic_parameter(parameter_declaration);
2618                 parameter_type = parameter_declaration->type;
2619
2620                 function_parameter_t *function_parameter
2621                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
2622                 memset(function_parameter, 0, sizeof(function_parameter[0]));
2623
2624                 function_parameter->type = parameter_type;
2625                 if(last_parameter != NULL) {
2626                         last_parameter->next = function_parameter;
2627                 } else {
2628                         parameters = function_parameter;
2629                 }
2630                 last_parameter = function_parameter;
2631         }
2632         new_type->function.parameters = parameters;
2633
2634         type = typehash_insert(new_type);
2635         if(type != new_type) {
2636                 obstack_free(type_obst, new_type);
2637         }
2638
2639         declaration->type = type;
2640 }
2641
2642 /**
2643  * Check if all labels are defined in the current function.
2644  */
2645 static void check_for_missing_labels(void)
2646 {
2647         bool first_err = true;
2648         for (const goto_statement_t *goto_statement = goto_first;
2649              goto_statement != NULL;
2650              goto_statement = goto_statement->next) {
2651                  const declaration_t *label = goto_statement->label;
2652
2653                  if (label->source_position.input_name == NULL) {
2654                          if (first_err) {
2655                                  first_err = false;
2656                                  diagnosticf("%s: In function '%Y':\n",
2657                                          current_function->source_position.input_name,
2658                                          current_function->symbol);
2659                          }
2660                          errorf(goto_statement->statement.source_position,
2661                                  "label '%Y' used but not defined", label->symbol);
2662                  }
2663         }
2664         goto_first = goto_last = NULL;
2665 }
2666
2667 static void parse_external_declaration(void)
2668 {
2669         /* function-definitions and declarations both start with declaration
2670          * specifiers */
2671         declaration_specifiers_t specifiers;
2672         memset(&specifiers, 0, sizeof(specifiers));
2673         parse_declaration_specifiers(&specifiers);
2674
2675         /* must be a declaration */
2676         if(token.type == ';') {
2677                 parse_anonymous_declaration_rest(&specifiers, append_declaration);
2678                 return;
2679         }
2680
2681         /* declarator is common to both function-definitions and declarations */
2682         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
2683
2684         /* must be a declaration */
2685         if(token.type == ',' || token.type == '=' || token.type == ';') {
2686                 parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
2687                 return;
2688         }
2689
2690         /* must be a function definition */
2691         parse_kr_declaration_list(ndeclaration);
2692
2693         if(token.type != '{') {
2694                 parse_error_expected("while parsing function definition", '{', 0);
2695                 eat_statement();
2696                 return;
2697         }
2698
2699         type_t *type = ndeclaration->type;
2700
2701         /* note that we don't skip typerefs: the standard doesn't allow them here
2702          * (so we can't use is_type_function here) */
2703         if(type->kind != TYPE_FUNCTION) {
2704                 if (is_type_valid(type)) {
2705                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
2706                                type, ndeclaration->symbol);
2707                 }
2708                 eat_block();
2709                 return;
2710         }
2711
2712         /* § 6.7.5.3 (14) a function definition with () means no
2713          * parameters (and not unspecified parameters) */
2714         if(type->function.unspecified_parameters) {
2715                 type_t *duplicate = duplicate_type(type);
2716                 duplicate->function.unspecified_parameters = false;
2717
2718                 type = typehash_insert(duplicate);
2719                 if(type != duplicate) {
2720                         obstack_free(type_obst, duplicate);
2721                 }
2722                 ndeclaration->type = type;
2723         }
2724
2725         declaration_t *const declaration = record_function_definition(ndeclaration);
2726         if(ndeclaration != declaration) {
2727                 declaration->context = ndeclaration->context;
2728         }
2729         type = skip_typeref(declaration->type);
2730
2731         /* push function parameters and switch context */
2732         int         top          = environment_top();
2733         context_t  *last_context = context;
2734         set_context(&declaration->context);
2735
2736         declaration_t *parameter = declaration->context.declarations;
2737         for( ; parameter != NULL; parameter = parameter->next) {
2738                 if(parameter->parent_context == &ndeclaration->context) {
2739                         parameter->parent_context = context;
2740                 }
2741                 assert(parameter->parent_context == NULL
2742                                 || parameter->parent_context == context);
2743                 parameter->parent_context = context;
2744                 environment_push(parameter);
2745         }
2746
2747         if(declaration->init.statement != NULL) {
2748                 parser_error_multiple_definition(declaration, token.source_position);
2749                 eat_block();
2750                 goto end_of_parse_external_declaration;
2751         } else {
2752                 /* parse function body */
2753                 int            label_stack_top      = label_top();
2754                 declaration_t *old_current_function = current_function;
2755                 current_function                    = declaration;
2756
2757                 declaration->init.statement = parse_compound_statement();
2758                 check_for_missing_labels();
2759
2760                 assert(current_function == declaration);
2761                 current_function = old_current_function;
2762                 label_pop_to(label_stack_top);
2763         }
2764
2765 end_of_parse_external_declaration:
2766         assert(context == &declaration->context);
2767         set_context(last_context);
2768         environment_pop_to(top);
2769 }
2770
2771 static type_t *make_bitfield_type(type_t *base, expression_t *size)
2772 {
2773         type_t *type        = allocate_type_zero(TYPE_BITFIELD);
2774         type->bitfield.base = base;
2775         type->bitfield.size = size;
2776
2777         return type;
2778 }
2779
2780 static void parse_struct_declarators(const declaration_specifiers_t *specifiers)
2781 {
2782         /* TODO: check constraints for struct declarations (in specifiers) */
2783         while(1) {
2784                 declaration_t *declaration;
2785
2786                 if(token.type == ':') {
2787                         next_token();
2788
2789                         type_t *base_type = specifiers->type;
2790                         expression_t *size = parse_constant_expression();
2791
2792                         type_t *type = make_bitfield_type(base_type, size);
2793
2794                         declaration = allocate_declaration_zero();
2795                         declaration->namespc         = NAMESPACE_NORMAL;
2796                         declaration->storage_class   = STORAGE_CLASS_NONE;
2797                         declaration->source_position = token.source_position;
2798                         declaration->modifiers       = specifiers->decl_modifiers;
2799                         declaration->type            = type;
2800                 } else {
2801                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
2802
2803                         if(token.type == ':') {
2804                                 next_token();
2805                                 expression_t *size = parse_constant_expression();
2806
2807                                 type_t *type = make_bitfield_type(declaration->type, size);
2808                                 declaration->type = type;
2809                         }
2810                 }
2811                 record_declaration(declaration);
2812
2813                 if(token.type != ',')
2814                         break;
2815                 next_token();
2816         }
2817         expect_void(';');
2818 }
2819
2820 static void parse_compound_type_entries(void)
2821 {
2822         eat('{');
2823
2824         while(token.type != '}' && token.type != T_EOF) {
2825                 declaration_specifiers_t specifiers;
2826                 memset(&specifiers, 0, sizeof(specifiers));
2827                 parse_declaration_specifiers(&specifiers);
2828
2829                 parse_struct_declarators(&specifiers);
2830         }
2831         if(token.type == T_EOF) {
2832                 errorf(HERE, "EOF while parsing struct");
2833         }
2834         next_token();
2835 }
2836
2837 static type_t *parse_typename(void)
2838 {
2839         declaration_specifiers_t specifiers;
2840         memset(&specifiers, 0, sizeof(specifiers));
2841         parse_declaration_specifiers(&specifiers);
2842         if(specifiers.storage_class != STORAGE_CLASS_NONE) {
2843                 /* TODO: improve error message, user does probably not know what a
2844                  * storage class is...
2845                  */
2846                 errorf(HERE, "typename may not have a storage class");
2847         }
2848
2849         type_t *result = parse_abstract_declarator(specifiers.type);
2850
2851         return result;
2852 }
2853
2854
2855
2856
2857 typedef expression_t* (*parse_expression_function) (unsigned precedence);
2858 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
2859                                                           expression_t *left);
2860
2861 typedef struct expression_parser_function_t expression_parser_function_t;
2862 struct expression_parser_function_t {
2863         unsigned                         precedence;
2864         parse_expression_function        parser;
2865         unsigned                         infix_precedence;
2866         parse_expression_infix_function  infix_parser;
2867 };
2868
2869 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
2870
2871 /**
2872  * Creates a new invalid expression.
2873  */
2874 static expression_t *create_invalid_expression(void)
2875 {
2876         expression_t *expression         = allocate_expression_zero(EXPR_INVALID);
2877         expression->base.source_position = token.source_position;
2878         return expression;
2879 }
2880
2881 /**
2882  * Prints an error message if an expression was expected but not read
2883  */
2884 static expression_t *expected_expression_error(void)
2885 {
2886         /* skip the error message if the error token was read */
2887         if (token.type != T_ERROR) {
2888                 errorf(HERE, "expected expression, got token '%K'", &token);
2889         }
2890         next_token();
2891
2892         return create_invalid_expression();
2893 }
2894
2895 /**
2896  * Parse a string constant.
2897  */
2898 static expression_t *parse_string_const(void)
2899 {
2900         expression_t *cnst  = allocate_expression_zero(EXPR_STRING_LITERAL);
2901         cnst->base.datatype = type_string;
2902         cnst->string.value  = parse_string_literals();
2903
2904         return cnst;
2905 }
2906
2907 /**
2908  * Parse a wide string constant.
2909  */
2910 static expression_t *parse_wide_string_const(void)
2911 {
2912         expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
2913         cnst->base.datatype      = type_wchar_t_ptr;
2914         cnst->wide_string.value  = token.v.wide_string; /* TODO concatenate */
2915         next_token();
2916         return cnst;
2917 }
2918
2919 /**
2920  * Parse an integer constant.
2921  */
2922 static expression_t *parse_int_const(void)
2923 {
2924         expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2925         cnst->base.datatype      = token.datatype;
2926         cnst->conste.v.int_value = token.v.intvalue;
2927
2928         next_token();
2929
2930         return cnst;
2931 }
2932
2933 /**
2934  * Parse a float constant.
2935  */
2936 static expression_t *parse_float_const(void)
2937 {
2938         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
2939         cnst->base.datatype        = token.datatype;
2940         cnst->conste.v.float_value = token.v.floatvalue;
2941
2942         next_token();
2943
2944         return cnst;
2945 }
2946
2947 static declaration_t *create_implicit_function(symbol_t *symbol,
2948                 const source_position_t source_position)
2949 {
2950         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
2951         ntype->function.return_type            = type_int;
2952         ntype->function.unspecified_parameters = true;
2953
2954         type_t *type = typehash_insert(ntype);
2955         if(type != ntype) {
2956                 free_type(ntype);
2957         }
2958
2959         declaration_t *const declaration = allocate_declaration_zero();
2960         declaration->storage_class   = STORAGE_CLASS_EXTERN;
2961         declaration->type            = type;
2962         declaration->symbol          = symbol;
2963         declaration->source_position = source_position;
2964         declaration->parent_context  = global_context;
2965
2966         context_t *old_context = context;
2967         set_context(global_context);
2968
2969         environment_push(declaration);
2970         /* prepend the declaration to the global declarations list */
2971         declaration->next     = context->declarations;
2972         context->declarations = declaration;
2973
2974         assert(context == global_context);
2975         set_context(old_context);
2976
2977         return declaration;
2978 }
2979
2980 /**
2981  * Creates a return_type (func)(argument_type) function type if not
2982  * already exists.
2983  *
2984  * @param return_type    the return type
2985  * @param argument_type  the argument type
2986  */
2987 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
2988 {
2989         function_parameter_t *parameter
2990                 = obstack_alloc(type_obst, sizeof(parameter[0]));
2991         memset(parameter, 0, sizeof(parameter[0]));
2992         parameter->type = argument_type;
2993
2994         type_t *type               = allocate_type_zero(TYPE_FUNCTION);
2995         type->function.return_type = return_type;
2996         type->function.parameters  = parameter;
2997
2998         type_t *result = typehash_insert(type);
2999         if(result != type) {
3000                 free_type(type);
3001         }
3002
3003         return result;
3004 }
3005
3006 /**
3007  * Creates a function type for some function like builtins.
3008  *
3009  * @param symbol   the symbol describing the builtin
3010  */
3011 static type_t *get_builtin_symbol_type(symbol_t *symbol)
3012 {
3013         switch(symbol->ID) {
3014         case T___builtin_alloca:
3015                 return make_function_1_type(type_void_ptr, type_size_t);
3016         case T___builtin_nan:
3017                 return make_function_1_type(type_double, type_string);
3018         case T___builtin_nanf:
3019                 return make_function_1_type(type_float, type_string);
3020         case T___builtin_nand:
3021                 return make_function_1_type(type_long_double, type_string);
3022         case T___builtin_va_end:
3023                 return make_function_1_type(type_void, type_valist);
3024         default:
3025                 panic("not implemented builtin symbol found");
3026         }
3027 }
3028
3029 /**
3030  * Performs automatic type cast as described in § 6.3.2.1.
3031  *
3032  * @param orig_type  the original type
3033  */
3034 static type_t *automatic_type_conversion(type_t *orig_type)
3035 {
3036         type_t *type = skip_typeref(orig_type);
3037         if(is_type_array(type)) {
3038                 array_type_t *array_type   = &type->array;
3039                 type_t       *element_type = array_type->element_type;
3040                 unsigned      qualifiers   = array_type->type.qualifiers;
3041
3042                 return make_pointer_type(element_type, qualifiers);
3043         }
3044
3045         if(is_type_function(type)) {
3046                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
3047         }
3048
3049         return orig_type;
3050 }
3051
3052 /**
3053  * reverts the automatic casts of array to pointer types and function
3054  * to function-pointer types as defined § 6.3.2.1
3055  */
3056 type_t *revert_automatic_type_conversion(const expression_t *expression)
3057 {
3058         switch (expression->kind) {
3059                 case EXPR_REFERENCE: return expression->reference.declaration->type;
3060                 case EXPR_SELECT:    return expression->select.compound_entry->type;
3061
3062                 case EXPR_UNARY_DEREFERENCE: {
3063                         const expression_t *const value = expression->unary.value;
3064                         type_t             *const type  = skip_typeref(value->base.datatype);
3065                         assert(is_type_pointer(type));
3066                         return type->pointer.points_to;
3067                 }
3068
3069                 case EXPR_BUILTIN_SYMBOL:
3070                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
3071
3072                 case EXPR_ARRAY_ACCESS: {
3073                         const expression_t *const array_ref = expression->array_access.array_ref;
3074                         type_t             *const type_left = skip_typeref(array_ref->base.datatype);
3075                         if (!is_type_valid(type_left))
3076                                 return type_left;
3077                         assert(is_type_pointer(type_left));
3078                         return type_left->pointer.points_to;
3079                 }
3080
3081                 default: break;
3082         }
3083
3084         return expression->base.datatype;
3085 }
3086
3087 static expression_t *parse_reference(void)
3088 {
3089         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
3090
3091         reference_expression_t *ref = &expression->reference;
3092         ref->symbol = token.v.symbol;
3093
3094         declaration_t *declaration = get_declaration(ref->symbol, NAMESPACE_NORMAL);
3095
3096         source_position_t source_position = token.source_position;
3097         next_token();
3098
3099         if(declaration == NULL) {
3100                 if (! strict_mode && token.type == '(') {
3101                         /* an implicitly defined function */
3102                         if (warning.implicit_function_declaration) {
3103                                 warningf(HERE, "implicit declaration of function '%Y'",
3104                                         ref->symbol);
3105                         }
3106
3107                         declaration = create_implicit_function(ref->symbol,
3108                                                                source_position);
3109                 } else {
3110                         errorf(HERE, "unknown symbol '%Y' found.", ref->symbol);
3111                         return expression;
3112                 }
3113         }
3114
3115         type_t *type         = declaration->type;
3116
3117         /* we always do the auto-type conversions; the & and sizeof parser contains
3118          * code to revert this! */
3119         type = automatic_type_conversion(type);
3120
3121         ref->declaration         = declaration;
3122         ref->expression.datatype = type;
3123
3124         return expression;
3125 }
3126
3127 static void check_cast_allowed(expression_t *expression, type_t *dest_type)
3128 {
3129         (void) expression;
3130         (void) dest_type;
3131         /* TODO check if explicit cast is allowed and issue warnings/errors */
3132 }
3133
3134 static expression_t *parse_cast(void)
3135 {
3136         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
3137
3138         cast->base.source_position = token.source_position;
3139
3140         type_t *type  = parse_typename();
3141
3142         expect(')');
3143         expression_t *value = parse_sub_expression(20);
3144
3145         check_cast_allowed(value, type);
3146
3147         cast->base.datatype = type;
3148         cast->unary.value   = value;
3149
3150         return cast;
3151 }
3152
3153 static expression_t *parse_statement_expression(void)
3154 {
3155         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
3156
3157         statement_t *statement           = parse_compound_statement();
3158         expression->statement.statement  = statement;
3159         expression->base.source_position = statement->base.source_position;
3160
3161         /* find last statement and use its type */
3162         type_t *type = type_void;
3163         const statement_t *stmt = statement->compound.statements;
3164         if (stmt != NULL) {
3165                 while (stmt->base.next != NULL)
3166                         stmt = stmt->base.next;
3167
3168                 if (stmt->kind == STATEMENT_EXPRESSION) {
3169                         type = stmt->expression.expression->base.datatype;
3170                 }
3171         } else {
3172                 warningf(expression->base.source_position, "empty statement expression ({})");
3173         }
3174         expression->base.datatype = type;
3175
3176         expect(')');
3177
3178         return expression;
3179 }
3180
3181 static expression_t *parse_brace_expression(void)
3182 {
3183         eat('(');
3184
3185         switch(token.type) {
3186         case '{':
3187                 /* gcc extension: a statement expression */
3188                 return parse_statement_expression();
3189
3190         TYPE_QUALIFIERS
3191         TYPE_SPECIFIERS
3192                 return parse_cast();
3193         case T_IDENTIFIER:
3194                 if(is_typedef_symbol(token.v.symbol)) {
3195                         return parse_cast();
3196                 }
3197         }
3198
3199         expression_t *result = parse_expression();
3200         expect(')');
3201
3202         return result;
3203 }
3204
3205 static expression_t *parse_function_keyword(void)
3206 {
3207         next_token();
3208         /* TODO */
3209
3210         if (current_function == NULL) {
3211                 errorf(HERE, "'__func__' used outside of a function");
3212         }
3213
3214         string_literal_expression_t *expression
3215                 = allocate_ast_zero(sizeof(expression[0]));
3216
3217         expression->expression.kind     = EXPR_FUNCTION;
3218         expression->expression.datatype = type_string;
3219
3220         return (expression_t*) expression;
3221 }
3222
3223 static expression_t *parse_pretty_function_keyword(void)
3224 {
3225         eat(T___PRETTY_FUNCTION__);
3226         /* TODO */
3227
3228         if (current_function == NULL) {
3229                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
3230         }
3231
3232         string_literal_expression_t *expression
3233                 = allocate_ast_zero(sizeof(expression[0]));
3234
3235         expression->expression.kind     = EXPR_PRETTY_FUNCTION;
3236         expression->expression.datatype = type_string;
3237
3238         return (expression_t*) expression;
3239 }
3240
3241 static designator_t *parse_designator(void)
3242 {
3243         designator_t *result = allocate_ast_zero(sizeof(result[0]));
3244
3245         if(token.type != T_IDENTIFIER) {
3246                 parse_error_expected("while parsing member designator",
3247                                      T_IDENTIFIER, 0);
3248                 eat_paren();
3249                 return NULL;
3250         }
3251         result->symbol = token.v.symbol;
3252         next_token();
3253
3254         designator_t *last_designator = result;
3255         while(true) {
3256                 if(token.type == '.') {
3257                         next_token();
3258                         if(token.type != T_IDENTIFIER) {
3259                                 parse_error_expected("while parsing member designator",
3260                                                      T_IDENTIFIER, 0);
3261                                 eat_paren();
3262                                 return NULL;
3263                         }
3264                         designator_t *designator = allocate_ast_zero(sizeof(result[0]));
3265                         designator->symbol       = token.v.symbol;
3266                         next_token();
3267
3268                         last_designator->next = designator;
3269                         last_designator       = designator;
3270                         continue;
3271                 }
3272                 if(token.type == '[') {
3273                         next_token();
3274                         designator_t *designator = allocate_ast_zero(sizeof(result[0]));
3275                         designator->array_access = parse_expression();
3276                         if(designator->array_access == NULL) {
3277                                 eat_paren();
3278                                 return NULL;
3279                         }
3280                         expect(']');
3281
3282                         last_designator->next = designator;
3283                         last_designator       = designator;
3284                         continue;
3285                 }
3286                 break;
3287         }
3288
3289         return result;
3290 }
3291
3292 static expression_t *parse_offsetof(void)
3293 {
3294         eat(T___builtin_offsetof);
3295
3296         expression_t *expression  = allocate_expression_zero(EXPR_OFFSETOF);
3297         expression->base.datatype = type_size_t;
3298
3299         expect('(');
3300         expression->offsetofe.type = parse_typename();
3301         expect(',');
3302         expression->offsetofe.designator = parse_designator();
3303         expect(')');
3304
3305         return expression;
3306 }
3307
3308 static expression_t *parse_va_start(void)
3309 {
3310         eat(T___builtin_va_start);
3311
3312         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
3313
3314         expect('(');
3315         expression->va_starte.ap = parse_assignment_expression();
3316         expect(',');
3317         expression_t *const expr = parse_assignment_expression();
3318         if (expr->kind == EXPR_REFERENCE) {
3319                 declaration_t *const decl = expr->reference.declaration;
3320                 if (decl->parent_context == &current_function->context &&
3321                     decl->next == NULL) {
3322                         expression->va_starte.parameter = decl;
3323                         expect(')');
3324                         return expression;
3325                 }
3326         }
3327         errorf(expr->base.source_position, "second argument of 'va_start' must be last parameter of the current function");
3328
3329         return create_invalid_expression();
3330 }
3331
3332 static expression_t *parse_va_arg(void)
3333 {
3334         eat(T___builtin_va_arg);
3335
3336         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
3337
3338         expect('(');
3339         expression->va_arge.ap = parse_assignment_expression();
3340         expect(',');
3341         expression->base.datatype = parse_typename();
3342         expect(')');
3343
3344         return expression;
3345 }
3346
3347 static expression_t *parse_builtin_symbol(void)
3348 {
3349         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
3350
3351         symbol_t *symbol = token.v.symbol;
3352
3353         expression->builtin_symbol.symbol = symbol;
3354         next_token();
3355
3356         type_t *type = get_builtin_symbol_type(symbol);
3357         type = automatic_type_conversion(type);
3358
3359         expression->base.datatype = type;
3360         return expression;
3361 }
3362
3363 static expression_t *parse_builtin_constant(void)
3364 {
3365         eat(T___builtin_constant_p);
3366
3367         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
3368
3369         expect('(');
3370         expression->builtin_constant.value = parse_assignment_expression();
3371         expect(')');
3372         expression->base.datatype = type_int;
3373
3374         return expression;
3375 }
3376
3377 static expression_t *parse_builtin_prefetch(void)
3378 {
3379         eat(T___builtin_prefetch);
3380
3381         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
3382
3383         expect('(');
3384         expression->builtin_prefetch.adr = parse_assignment_expression();
3385         if (token.type == ',') {
3386                 next_token();
3387                 expression->builtin_prefetch.rw = parse_assignment_expression();
3388         }
3389         if (token.type == ',') {
3390                 next_token();
3391                 expression->builtin_prefetch.locality = parse_assignment_expression();
3392         }
3393         expect(')');
3394         expression->base.datatype = type_void;
3395
3396         return expression;
3397 }
3398
3399 static expression_t *parse_compare_builtin(void)
3400 {
3401         expression_t *expression;
3402
3403         switch(token.type) {
3404         case T___builtin_isgreater:
3405                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
3406                 break;
3407         case T___builtin_isgreaterequal:
3408                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
3409                 break;
3410         case T___builtin_isless:
3411                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
3412                 break;
3413         case T___builtin_islessequal:
3414                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
3415                 break;
3416         case T___builtin_islessgreater:
3417                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
3418                 break;
3419         case T___builtin_isunordered:
3420                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
3421                 break;
3422         default:
3423                 panic("invalid compare builtin found");
3424                 break;
3425         }
3426         next_token();
3427
3428         expect('(');
3429         expression->binary.left = parse_assignment_expression();
3430         expect(',');
3431         expression->binary.right = parse_assignment_expression();
3432         expect(')');
3433
3434         type_t *const orig_type_left  = expression->binary.left->base.datatype;
3435         type_t *const orig_type_right = expression->binary.right->base.datatype;
3436
3437         type_t *const type_left  = skip_typeref(orig_type_left);
3438         type_t *const type_right = skip_typeref(orig_type_right);
3439         if(!is_type_floating(type_left) && !is_type_floating(type_right)) {
3440                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
3441                         type_error_incompatible("invalid operands in comparison",
3442                                 token.source_position, orig_type_left, orig_type_right);
3443                 }
3444         } else {
3445                 semantic_comparison(&expression->binary);
3446         }
3447
3448         return expression;
3449 }
3450
3451 static expression_t *parse_builtin_expect(void)
3452 {
3453         eat(T___builtin_expect);
3454
3455         expression_t *expression
3456                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
3457
3458         expect('(');
3459         expression->binary.left = parse_assignment_expression();
3460         expect(',');
3461         expression->binary.right = parse_constant_expression();
3462         expect(')');
3463
3464         expression->base.datatype = expression->binary.left->base.datatype;
3465
3466         return expression;
3467 }
3468
3469 static expression_t *parse_assume(void) {
3470         eat(T_assume);
3471
3472         expression_t *expression
3473                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
3474
3475         expect('(');
3476         expression->unary.value = parse_assignment_expression();
3477         expect(')');
3478
3479         expression->base.datatype = type_void;
3480         return expression;
3481 }
3482
3483 static expression_t *parse_alignof(void) {
3484         eat(T___alignof__);
3485
3486         expression_t *expression
3487                 = allocate_expression_zero(EXPR_ALIGNOF);
3488
3489         expect('(');
3490         expression->alignofe.type = parse_typename();
3491         expect(')');
3492
3493         expression->base.datatype = type_size_t;
3494         return expression;
3495 }
3496
3497 static expression_t *parse_primary_expression(void)
3498 {
3499         switch(token.type) {
3500         case T_INTEGER:
3501                 return parse_int_const();
3502         case T_FLOATINGPOINT:
3503                 return parse_float_const();
3504         case T_STRING_LITERAL:
3505                 return parse_string_const();
3506         case T_WIDE_STRING_LITERAL:
3507                 return parse_wide_string_const();
3508         case T_IDENTIFIER:
3509                 return parse_reference();
3510         case T___FUNCTION__:
3511         case T___func__:
3512                 return parse_function_keyword();
3513         case T___PRETTY_FUNCTION__:
3514                 return parse_pretty_function_keyword();
3515         case T___builtin_offsetof:
3516                 return parse_offsetof();
3517         case T___builtin_va_start:
3518                 return parse_va_start();
3519         case T___builtin_va_arg:
3520                 return parse_va_arg();
3521         case T___builtin_expect:
3522                 return parse_builtin_expect();
3523         case T___builtin_nanf:
3524         case T___builtin_alloca:
3525         case T___builtin_va_end:
3526                 return parse_builtin_symbol();
3527         case T___builtin_isgreater:
3528         case T___builtin_isgreaterequal:
3529         case T___builtin_isless:
3530         case T___builtin_islessequal:
3531         case T___builtin_islessgreater:
3532         case T___builtin_isunordered:
3533                 return parse_compare_builtin();
3534         case T___builtin_constant_p:
3535                 return parse_builtin_constant();
3536         case T___builtin_prefetch:
3537                 return parse_builtin_prefetch();
3538         case T___alignof__:
3539                 return parse_alignof();
3540         case T_assume:
3541                 return parse_assume();
3542
3543         case '(':
3544                 return parse_brace_expression();
3545         }
3546
3547         errorf(HERE, "unexpected token '%K'", &token);
3548         eat_statement();
3549
3550         return create_invalid_expression();
3551 }
3552
3553 /**
3554  * Check if the expression has the character type and issue a warning then.
3555  */
3556 static void check_for_char_index_type(const expression_t *expression) {
3557         type_t       *const type      = expression->base.datatype;
3558         const type_t *const base_type = skip_typeref(type);
3559
3560         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
3561                         warning.char_subscripts) {
3562                 warningf(expression->base.source_position,
3563                         "array subscript has type '%T'", type);
3564         }
3565 }
3566
3567 static expression_t *parse_array_expression(unsigned precedence,
3568                                             expression_t *left)
3569 {
3570         (void) precedence;
3571
3572         eat('[');
3573
3574         expression_t *inside = parse_expression();
3575
3576         array_access_expression_t *array_access
3577                 = allocate_ast_zero(sizeof(array_access[0]));
3578
3579         array_access->expression.kind = EXPR_ARRAY_ACCESS;
3580
3581         type_t *const orig_type_left   = left->base.datatype;
3582         type_t *const orig_type_inside = inside->base.datatype;
3583
3584         type_t *const type_left   = skip_typeref(orig_type_left);
3585         type_t *const type_inside = skip_typeref(orig_type_inside);
3586
3587         type_t *return_type;
3588         if (is_type_pointer(type_left)) {
3589                 return_type             = type_left->pointer.points_to;
3590                 array_access->array_ref = left;
3591                 array_access->index     = inside;
3592                 check_for_char_index_type(inside);
3593         } else if (is_type_pointer(type_inside)) {
3594                 return_type             = type_inside->pointer.points_to;
3595                 array_access->array_ref = inside;
3596                 array_access->index     = left;
3597                 array_access->flipped   = true;
3598                 check_for_char_index_type(left);
3599         } else {
3600                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
3601                         errorf(HERE,
3602                                 "array access on object with non-pointer types '%T', '%T'",
3603                                 orig_type_left, orig_type_inside);
3604                 }
3605                 return_type             = type_error_type;
3606                 array_access->array_ref = create_invalid_expression();
3607         }
3608
3609         if(token.type != ']') {
3610                 parse_error_expected("Problem while parsing array access", ']', 0);
3611                 return (expression_t*) array_access;
3612         }
3613         next_token();
3614
3615         return_type = automatic_type_conversion(return_type);
3616         array_access->expression.datatype = return_type;
3617
3618         return (expression_t*) array_access;
3619 }
3620
3621 static expression_t *parse_sizeof(unsigned precedence)
3622 {
3623         eat(T_sizeof);
3624
3625         sizeof_expression_t *sizeof_expression
3626                 = allocate_ast_zero(sizeof(sizeof_expression[0]));
3627         sizeof_expression->expression.kind     = EXPR_SIZEOF;
3628         sizeof_expression->expression.datatype = type_size_t;
3629
3630         if(token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
3631                 next_token();
3632                 sizeof_expression->type = parse_typename();
3633                 expect(')');
3634         } else {
3635                 expression_t *expression  = parse_sub_expression(precedence);
3636                 expression->base.datatype = revert_automatic_type_conversion(expression);
3637
3638                 sizeof_expression->type            = expression->base.datatype;
3639                 sizeof_expression->size_expression = expression;
3640         }
3641
3642         return (expression_t*) sizeof_expression;
3643 }
3644
3645 static expression_t *parse_select_expression(unsigned precedence,
3646                                              expression_t *compound)
3647 {
3648         (void) precedence;
3649         assert(token.type == '.' || token.type == T_MINUSGREATER);
3650
3651         bool is_pointer = (token.type == T_MINUSGREATER);
3652         next_token();
3653
3654         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
3655         select->select.compound = compound;
3656
3657         if(token.type != T_IDENTIFIER) {
3658                 parse_error_expected("while parsing select", T_IDENTIFIER, 0);
3659                 return select;
3660         }
3661         symbol_t *symbol      = token.v.symbol;
3662         select->select.symbol = symbol;
3663         next_token();
3664
3665         type_t *const orig_type = compound->base.datatype;
3666         type_t *const type      = skip_typeref(orig_type);
3667
3668         type_t *type_left = type;
3669         if(is_pointer) {
3670                 if (!is_type_pointer(type)) {
3671                         if (is_type_valid(type)) {
3672                                 errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
3673                         }
3674                         return create_invalid_expression();
3675                 }
3676                 type_left = type->pointer.points_to;
3677         }
3678         type_left = skip_typeref(type_left);
3679
3680         if (type_left->kind != TYPE_COMPOUND_STRUCT &&
3681             type_left->kind != TYPE_COMPOUND_UNION) {
3682                 if (is_type_valid(type_left)) {
3683                         errorf(HERE, "request for member '%Y' in something not a struct or "
3684                                "union, but '%T'", symbol, type_left);
3685                 }
3686                 return create_invalid_expression();
3687         }
3688
3689         declaration_t *const declaration = type_left->compound.declaration;
3690
3691         if(!declaration->init.is_defined) {
3692                 errorf(HERE, "request for member '%Y' of incomplete type '%T'",
3693                        symbol, type_left);
3694                 return create_invalid_expression();
3695         }
3696
3697         declaration_t *iter = declaration->context.declarations;
3698         for( ; iter != NULL; iter = iter->next) {
3699                 if(iter->symbol == symbol) {
3700                         break;
3701                 }
3702         }
3703         if(iter == NULL) {
3704                 errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
3705                 return create_invalid_expression();
3706         }
3707
3708         /* we always do the auto-type conversions; the & and sizeof parser contains
3709          * code to revert this! */
3710         type_t *expression_type = automatic_type_conversion(iter->type);
3711
3712         select->select.compound_entry = iter;
3713         select->base.datatype         = expression_type;
3714
3715         if(expression_type->kind == TYPE_BITFIELD) {
3716                 expression_t *extract
3717                         = allocate_expression_zero(EXPR_UNARY_BITFIELD_EXTRACT);
3718                 extract->unary.value   = select;
3719                 extract->base.datatype = expression_type->bitfield.base;
3720
3721                 return extract;
3722         }
3723
3724         return select;
3725 }
3726
3727 /**
3728  * Parse a call expression, ie. expression '( ... )'.
3729  *
3730  * @param expression  the function address
3731  */
3732 static expression_t *parse_call_expression(unsigned precedence,
3733                                            expression_t *expression)
3734 {
3735         (void) precedence;
3736         expression_t *result = allocate_expression_zero(EXPR_CALL);
3737
3738         call_expression_t *call = &result->call;
3739         call->function          = expression;
3740
3741         type_t *const orig_type = expression->base.datatype;
3742         type_t *const type      = skip_typeref(orig_type);
3743
3744         function_type_t *function_type = NULL;
3745         if (is_type_pointer(type)) {
3746                 type_t *const to_type = skip_typeref(type->pointer.points_to);
3747
3748                 if (is_type_function(to_type)) {
3749                         function_type             = &to_type->function;
3750                         call->expression.datatype = function_type->return_type;
3751                 }
3752         }
3753
3754         if (function_type == NULL && is_type_valid(type)) {
3755                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
3756         }
3757
3758         /* parse arguments */
3759         eat('(');
3760
3761         if(token.type != ')') {
3762                 call_argument_t *last_argument = NULL;
3763
3764                 while(true) {
3765                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
3766
3767                         argument->expression = parse_assignment_expression();
3768                         if(last_argument == NULL) {
3769                                 call->arguments = argument;
3770                         } else {
3771                                 last_argument->next = argument;
3772                         }
3773                         last_argument = argument;
3774
3775                         if(token.type != ',')
3776                                 break;
3777                         next_token();
3778                 }
3779         }
3780         expect(')');
3781
3782         if(function_type != NULL) {
3783                 function_parameter_t *parameter = function_type->parameters;
3784                 call_argument_t      *argument  = call->arguments;
3785                 for( ; parameter != NULL && argument != NULL;
3786                                 parameter = parameter->next, argument = argument->next) {
3787                         type_t *expected_type = parameter->type;
3788                         /* TODO report context in error messages */
3789                         expression_t *const arg_expr = argument->expression;
3790                         type_t       *const res_type = semantic_assign(expected_type, arg_expr, "function call");
3791                         if (res_type == NULL) {
3792                                 /* TODO improve error message */
3793                                 errorf(arg_expr->base.source_position,
3794                                         "Cannot call function with argument '%E' of type '%T' where type '%T' is expected",
3795                                         arg_expr, arg_expr->base.datatype, expected_type);
3796                         } else {
3797                                 argument->expression = create_implicit_cast(argument->expression, expected_type);
3798                         }
3799                 }
3800                 /* too few parameters */
3801                 if(parameter != NULL) {
3802                         errorf(HERE, "too few arguments to function '%E'", expression);
3803                 } else if(argument != NULL) {
3804                         /* too many parameters */
3805                         if(!function_type->variadic
3806                                         && !function_type->unspecified_parameters) {
3807                                 errorf(HERE, "too many arguments to function '%E'", expression);
3808                         } else {
3809                                 /* do default promotion */
3810                                 for( ; argument != NULL; argument = argument->next) {
3811                                         type_t *type = argument->expression->base.datatype;
3812
3813                                         type = skip_typeref(type);
3814                                         if(is_type_integer(type)) {
3815                                                 type = promote_integer(type);
3816                                         } else if(type == type_float) {
3817                                                 type = type_double;
3818                                         }
3819
3820                                         argument->expression
3821                                                 = create_implicit_cast(argument->expression, type);
3822                                 }
3823
3824                                 check_format(&result->call);
3825                         }
3826                 } else {
3827                         check_format(&result->call);
3828                 }
3829         }
3830
3831         return result;
3832 }
3833
3834 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
3835
3836 static bool same_compound_type(const type_t *type1, const type_t *type2)
3837 {
3838         return
3839                 is_type_compound(type1) &&
3840                 type1->kind == type2->kind &&
3841                 type1->compound.declaration == type2->compound.declaration;
3842 }
3843
3844 /**
3845  * Parse a conditional expression, ie. 'expression ? ... : ...'.
3846  *
3847  * @param expression  the conditional expression
3848  */
3849 static expression_t *parse_conditional_expression(unsigned precedence,
3850                                                   expression_t *expression)
3851 {
3852         eat('?');
3853
3854         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
3855
3856         conditional_expression_t *conditional = &result->conditional;
3857         conditional->condition = expression;
3858
3859         /* 6.5.15.2 */
3860         type_t *const condition_type_orig = expression->base.datatype;
3861         type_t *const condition_type      = skip_typeref(condition_type_orig);
3862         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
3863                 type_error("expected a scalar type in conditional condition",
3864                            expression->base.source_position, condition_type_orig);
3865         }
3866
3867         expression_t *true_expression = parse_expression();
3868         expect(':');
3869         expression_t *false_expression = parse_sub_expression(precedence);
3870
3871         conditional->true_expression  = true_expression;
3872         conditional->false_expression = false_expression;
3873
3874         type_t *const orig_true_type  = true_expression->base.datatype;
3875         type_t *const orig_false_type = false_expression->base.datatype;
3876         type_t *const true_type       = skip_typeref(orig_true_type);
3877         type_t *const false_type      = skip_typeref(orig_false_type);
3878
3879         /* 6.5.15.3 */
3880         type_t *result_type;
3881         if (is_type_arithmetic(true_type) && is_type_arithmetic(false_type)) {
3882                 result_type = semantic_arithmetic(true_type, false_type);
3883
3884                 true_expression  = create_implicit_cast(true_expression, result_type);
3885                 false_expression = create_implicit_cast(false_expression, result_type);
3886
3887                 conditional->true_expression     = true_expression;
3888                 conditional->false_expression    = false_expression;
3889                 conditional->expression.datatype = result_type;
3890         } else if (same_compound_type(true_type, false_type) || (
3891             is_type_atomic(true_type, ATOMIC_TYPE_VOID) &&
3892             is_type_atomic(false_type, ATOMIC_TYPE_VOID)
3893                 )) {
3894                 /* just take 1 of the 2 types */
3895                 result_type = true_type;
3896         } else if (is_type_pointer(true_type) && is_type_pointer(false_type)
3897                         && pointers_compatible(true_type, false_type)) {
3898                 /* ok */
3899                 result_type = true_type;
3900         } else {
3901                 /* TODO */
3902                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
3903                         type_error_incompatible("while parsing conditional",
3904                                                 expression->base.source_position, true_type,
3905                                                 false_type);
3906                 }
3907                 result_type = type_error_type;
3908         }
3909
3910         conditional->expression.datatype = result_type;
3911         return result;
3912 }
3913
3914 /**
3915  * Parse an extension expression.
3916  */
3917 static expression_t *parse_extension(unsigned precedence)
3918 {
3919         eat(T___extension__);
3920
3921         /* TODO enable extensions */
3922         expression_t *expression = parse_sub_expression(precedence);
3923         /* TODO disable extensions */
3924         return expression;
3925 }
3926
3927 static expression_t *parse_builtin_classify_type(const unsigned precedence)
3928 {
3929         eat(T___builtin_classify_type);
3930
3931         expression_t *result  = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
3932         result->base.datatype = type_int;
3933
3934         expect('(');
3935         expression_t *expression = parse_sub_expression(precedence);
3936         expect(')');
3937         result->classify_type.type_expression = expression;
3938
3939         return result;
3940 }
3941
3942 static void semantic_incdec(unary_expression_t *expression)
3943 {
3944         type_t *const orig_type = expression->value->base.datatype;
3945         type_t *const type      = skip_typeref(orig_type);
3946         if(!is_type_arithmetic(type) && type->kind != TYPE_POINTER) {
3947                 if (is_type_valid(type)) {
3948                         /* TODO: improve error message */
3949                         errorf(HERE, "operation needs an arithmetic or pointer type");
3950                 }
3951                 return;
3952         }
3953
3954         expression->expression.datatype = orig_type;
3955 }
3956
3957 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
3958 {
3959         type_t *const orig_type = expression->value->base.datatype;
3960         type_t *const type      = skip_typeref(orig_type);
3961         if(!is_type_arithmetic(type)) {
3962                 if (is_type_valid(type)) {
3963                         /* TODO: improve error message */
3964                         errorf(HERE, "operation needs an arithmetic type");
3965                 }
3966                 return;
3967         }
3968
3969         expression->expression.datatype = orig_type;
3970 }
3971
3972 static void semantic_unexpr_scalar(unary_expression_t *expression)
3973 {
3974         type_t *const orig_type = expression->value->base.datatype;
3975         type_t *const type      = skip_typeref(orig_type);
3976         if (!is_type_scalar(type)) {
3977                 if (is_type_valid(type)) {
3978                         errorf(HERE, "operand of ! must be of scalar type");
3979                 }
3980                 return;
3981         }
3982
3983         expression->expression.datatype = orig_type;
3984 }
3985
3986 static void semantic_unexpr_integer(unary_expression_t *expression)
3987 {
3988         type_t *const orig_type = expression->value->base.datatype;
3989         type_t *const type      = skip_typeref(orig_type);
3990         if (!is_type_integer(type)) {
3991                 if (is_type_valid(type)) {
3992                         errorf(HERE, "operand of ~ must be of integer type");
3993                 }
3994                 return;
3995         }
3996
3997         expression->expression.datatype = orig_type;
3998 }
3999
4000 static void semantic_dereference(unary_expression_t *expression)
4001 {
4002         type_t *const orig_type = expression->value->base.datatype;
4003         type_t *const type      = skip_typeref(orig_type);
4004         if(!is_type_pointer(type)) {
4005                 if (is_type_valid(type)) {
4006                         errorf(HERE, "Unary '*' needs pointer or arrray type, but type '%T' given", orig_type);
4007                 }
4008                 return;
4009         }
4010
4011         type_t *result_type = type->pointer.points_to;
4012         result_type = automatic_type_conversion(result_type);
4013         expression->expression.datatype = result_type;
4014 }
4015
4016 /**
4017  * Check the semantic of the address taken expression.
4018  */
4019 static void semantic_take_addr(unary_expression_t *expression)
4020 {
4021         expression_t *value  = expression->value;
4022         value->base.datatype = revert_automatic_type_conversion(value);
4023
4024         type_t *orig_type = value->base.datatype;
4025         if(!is_type_valid(orig_type))
4026                 return;
4027
4028         if(value->kind == EXPR_REFERENCE) {
4029                 declaration_t *const declaration = value->reference.declaration;
4030                 if(declaration != NULL) {
4031                         if (declaration->storage_class == STORAGE_CLASS_REGISTER) {
4032                                 errorf(expression->expression.source_position,
4033                                         "address of register variable '%Y' requested",
4034                                         declaration->symbol);
4035                         }
4036                         declaration->address_taken = 1;
4037                 }
4038         }
4039
4040         expression->expression.datatype = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
4041 }
4042
4043 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc)   \
4044 static expression_t *parse_##unexpression_type(unsigned precedence)            \
4045 {                                                                              \
4046         eat(token_type);                                                           \
4047                                                                                    \
4048         expression_t *unary_expression                                             \
4049                 = allocate_expression_zero(unexpression_type);                         \
4050         unary_expression->base.source_position = HERE;                             \
4051         unary_expression->unary.value = parse_sub_expression(precedence);          \
4052                                                                                    \
4053         sfunc(&unary_expression->unary);                                           \
4054                                                                                    \
4055         return unary_expression;                                                   \
4056 }
4057
4058 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
4059                                semantic_unexpr_arithmetic)
4060 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
4061                                semantic_unexpr_arithmetic)
4062 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
4063                                semantic_unexpr_scalar)
4064 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
4065                                semantic_dereference)
4066 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
4067                                semantic_take_addr)
4068 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
4069                                semantic_unexpr_integer)
4070 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
4071                                semantic_incdec)
4072 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
4073                                semantic_incdec)
4074
4075 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
4076                                                sfunc)                         \
4077 static expression_t *parse_##unexpression_type(unsigned precedence,           \
4078                                                expression_t *left)            \
4079 {                                                                             \
4080         (void) precedence;                                                        \
4081         eat(token_type);                                                          \
4082                                                                               \
4083         expression_t *unary_expression                                            \
4084                 = allocate_expression_zero(unexpression_type);                        \
4085         unary_expression->unary.value = left;                                     \
4086                                                                                   \
4087         sfunc(&unary_expression->unary);                                          \
4088                                                                               \
4089         return unary_expression;                                                  \
4090 }
4091
4092 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
4093                                        EXPR_UNARY_POSTFIX_INCREMENT,
4094                                        semantic_incdec)
4095 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
4096                                        EXPR_UNARY_POSTFIX_DECREMENT,
4097                                        semantic_incdec)
4098
4099 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
4100 {
4101         /* TODO: handle complex + imaginary types */
4102
4103         /* § 6.3.1.8 Usual arithmetic conversions */
4104         if(type_left == type_long_double || type_right == type_long_double) {
4105                 return type_long_double;
4106         } else if(type_left == type_double || type_right == type_double) {
4107                 return type_double;
4108         } else if(type_left == type_float || type_right == type_float) {
4109                 return type_float;
4110         }
4111
4112         type_right = promote_integer(type_right);
4113         type_left  = promote_integer(type_left);
4114
4115         if(type_left == type_right)
4116                 return type_left;
4117
4118         bool signed_left  = is_type_signed(type_left);
4119         bool signed_right = is_type_signed(type_right);
4120         int  rank_left    = get_rank(type_left);
4121         int  rank_right   = get_rank(type_right);
4122         if(rank_left < rank_right) {
4123                 if(signed_left == signed_right || !signed_right) {
4124                         return type_right;
4125                 } else {
4126                         return type_left;
4127                 }
4128         } else {
4129                 if(signed_left == signed_right || !signed_left) {
4130                         return type_left;
4131                 } else {
4132                         return type_right;
4133                 }
4134         }
4135 }
4136
4137 /**
4138  * Check the semantic restrictions for a binary expression.
4139  */
4140 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
4141 {
4142         expression_t *const left            = expression->left;
4143         expression_t *const right           = expression->right;
4144         type_t       *const orig_type_left  = left->base.datatype;
4145         type_t       *const orig_type_right = right->base.datatype;
4146         type_t       *const type_left       = skip_typeref(orig_type_left);
4147         type_t       *const type_right      = skip_typeref(orig_type_right);
4148
4149         if(!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
4150                 /* TODO: improve error message */
4151                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
4152                         errorf(HERE, "operation needs arithmetic types");
4153                 }
4154                 return;
4155         }
4156
4157         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
4158         expression->left  = create_implicit_cast(left, arithmetic_type);
4159         expression->right = create_implicit_cast(right, arithmetic_type);
4160         expression->expression.datatype = arithmetic_type;
4161 }
4162
4163 static void semantic_shift_op(binary_expression_t *expression)
4164 {
4165         expression_t *const left            = expression->left;
4166         expression_t *const right           = expression->right;
4167         type_t       *const orig_type_left  = left->base.datatype;
4168         type_t       *const orig_type_right = right->base.datatype;
4169         type_t       *      type_left       = skip_typeref(orig_type_left);
4170         type_t       *      type_right      = skip_typeref(orig_type_right);
4171
4172         if(!is_type_integer(type_left) || !is_type_integer(type_right)) {
4173                 /* TODO: improve error message */
4174                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
4175                         errorf(HERE, "operation needs integer types");
4176                 }
4177                 return;
4178         }
4179
4180         type_left  = promote_integer(type_left);
4181         type_right = promote_integer(type_right);
4182
4183         expression->left  = create_implicit_cast(left, type_left);
4184         expression->right = create_implicit_cast(right, type_right);
4185         expression->expression.datatype = type_left;
4186 }
4187
4188 static void semantic_add(binary_expression_t *expression)
4189 {
4190         expression_t *const left            = expression->left;
4191         expression_t *const right           = expression->right;
4192         type_t       *const orig_type_left  = left->base.datatype;
4193         type_t       *const orig_type_right = right->base.datatype;
4194         type_t       *const type_left       = skip_typeref(orig_type_left);
4195         type_t       *const type_right      = skip_typeref(orig_type_right);
4196
4197         /* § 5.6.5 */
4198         if(is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
4199                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
4200                 expression->left  = create_implicit_cast(left, arithmetic_type);
4201                 expression->right = create_implicit_cast(right, arithmetic_type);
4202                 expression->expression.datatype = arithmetic_type;
4203                 return;
4204         } else if(is_type_pointer(type_left) && is_type_integer(type_right)) {
4205                 expression->expression.datatype = type_left;
4206         } else if(is_type_pointer(type_right) && is_type_integer(type_left)) {
4207                 expression->expression.datatype = type_right;
4208         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
4209                 errorf(HERE, "invalid operands to binary + ('%T', '%T')", orig_type_left, orig_type_right);
4210         }
4211 }
4212
4213 static void semantic_sub(binary_expression_t *expression)
4214 {
4215         expression_t *const left            = expression->left;
4216         expression_t *const right           = expression->right;
4217         type_t       *const orig_type_left  = left->base.datatype;
4218         type_t       *const orig_type_right = right->base.datatype;
4219         type_t       *const type_left       = skip_typeref(orig_type_left);
4220         type_t       *const type_right      = skip_typeref(orig_type_right);
4221
4222         /* § 5.6.5 */
4223         if(is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
4224                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
4225                 expression->left  = create_implicit_cast(left, arithmetic_type);
4226                 expression->right = create_implicit_cast(right, arithmetic_type);
4227                 expression->expression.datatype = arithmetic_type;
4228                 return;
4229         } else if(is_type_pointer(type_left) && is_type_integer(type_right)) {
4230                 expression->expression.datatype = type_left;
4231         } else if(is_type_pointer(type_left) && is_type_pointer(type_right)) {
4232                 if(!pointers_compatible(type_left, type_right)) {
4233                         errorf(HERE, "pointers to incompatible objects to binary '-' ('%T', '%T')", orig_type_left, orig_type_right);
4234                 } else {
4235                         expression->expression.datatype = type_ptrdiff_t;
4236                 }
4237         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
4238                 errorf(HERE, "invalid operands to binary '-' ('%T', '%T')", orig_type_left, orig_type_right);
4239         }
4240 }
4241
4242 static void semantic_comparison(binary_expression_t *expression)
4243 {
4244         expression_t *left            = expression->left;
4245         expression_t *right           = expression->right;
4246         type_t       *orig_type_left  = left->base.datatype;
4247         type_t       *orig_type_right = right->base.datatype;
4248
4249         type_t *type_left  = skip_typeref(orig_type_left);
4250         type_t *type_right = skip_typeref(orig_type_right);
4251
4252         /* TODO non-arithmetic types */
4253         if(is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
4254                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
4255                 expression->left  = create_implicit_cast(left, arithmetic_type);
4256                 expression->right = create_implicit_cast(right, arithmetic_type);
4257                 expression->expression.datatype = arithmetic_type;
4258         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
4259                 /* TODO check compatibility */
4260         } else if (is_type_pointer(type_left)) {
4261                 expression->right = create_implicit_cast(right, type_left);
4262         } else if (is_type_pointer(type_right)) {
4263                 expression->left = create_implicit_cast(left, type_right);
4264         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
4265                 type_error_incompatible("invalid operands in comparison",
4266                                         token.source_position, type_left, type_right);
4267         }
4268         expression->expression.datatype = type_int;
4269 }
4270
4271 static void semantic_arithmetic_assign(binary_expression_t *expression)
4272 {
4273         expression_t *left            = expression->left;
4274         expression_t *right           = expression->right;
4275         type_t       *orig_type_left  = left->base.datatype;
4276         type_t       *orig_type_right = right->base.datatype;
4277
4278         type_t *type_left  = skip_typeref(orig_type_left);
4279         type_t *type_right = skip_typeref(orig_type_right);
4280
4281         if(!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
4282                 /* TODO: improve error message */
4283                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
4284                         errorf(HERE, "operation needs arithmetic types");
4285                 }
4286                 return;
4287         }
4288
4289         /* combined instructions are tricky. We can't create an implicit cast on
4290          * the left side, because we need the uncasted form for the store.
4291          * The ast2firm pass has to know that left_type must be right_type
4292          * for the arithmetic operation and create a cast by itself */
4293         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
4294         expression->right       = create_implicit_cast(right, arithmetic_type);
4295         expression->expression.datatype = type_left;
4296 }
4297
4298 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
4299 {
4300         expression_t *const left            = expression->left;
4301         expression_t *const right           = expression->right;
4302         type_t       *const orig_type_left  = left->base.datatype;
4303         type_t       *const orig_type_right = right->base.datatype;
4304         type_t       *const type_left       = skip_typeref(orig_type_left);
4305         type_t       *const type_right      = skip_typeref(orig_type_right);
4306
4307         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
4308                 /* combined instructions are tricky. We can't create an implicit cast on
4309                  * the left side, because we need the uncasted form for the store.
4310                  * The ast2firm pass has to know that left_type must be right_type
4311                  * for the arithmetic operation and create a cast by itself */
4312                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
4313                 expression->right = create_implicit_cast(right, arithmetic_type);
4314                 expression->expression.datatype = type_left;
4315         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
4316                 expression->expression.datatype = type_left;
4317         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
4318                 errorf(HERE, "incompatible types '%T' and '%T' in assignment", orig_type_left, orig_type_right);
4319         }
4320 }
4321
4322 /**
4323  * Check the semantic restrictions of a logical expression.
4324  */
4325 static void semantic_logical_op(binary_expression_t *expression)
4326 {
4327         expression_t *const left            = expression->left;
4328         expression_t *const right           = expression->right;
4329         type_t       *const orig_type_left  = left->base.datatype;
4330         type_t       *const orig_type_right = right->base.datatype;
4331         type_t       *const type_left       = skip_typeref(orig_type_left);
4332         type_t       *const type_right      = skip_typeref(orig_type_right);
4333
4334         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
4335                 /* TODO: improve error message */
4336                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
4337                         errorf(HERE, "operation needs scalar types");
4338                 }
4339                 return;
4340         }
4341
4342         expression->expression.datatype = type_int;
4343 }
4344
4345 /**
4346  * Checks if a compound type has constant fields.
4347  */
4348 static bool has_const_fields(const compound_type_t *type)
4349 {
4350         const context_t     *context = &type->declaration->context;
4351         const declaration_t *declaration = context->declarations;
4352
4353         for (; declaration != NULL; declaration = declaration->next) {
4354                 if (declaration->namespc != NAMESPACE_NORMAL)
4355                         continue;
4356
4357                 const type_t *decl_type = skip_typeref(declaration->type);
4358                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
4359                         return true;
4360         }
4361         /* TODO */
4362         return false;
4363 }
4364
4365 /**
4366  * Check the semantic restrictions of a binary assign expression.
4367  */
4368 static void semantic_binexpr_assign(binary_expression_t *expression)
4369 {
4370         expression_t *left           = expression->left;
4371         type_t       *orig_type_left = left->base.datatype;
4372
4373         type_t *type_left = revert_automatic_type_conversion(left);
4374         type_left         = skip_typeref(orig_type_left);
4375
4376         /* must be a modifiable lvalue */
4377         if (is_type_array(type_left)) {
4378                 errorf(HERE, "cannot assign to arrays ('%E')", left);
4379                 return;
4380         }
4381         if(type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
4382                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
4383                        orig_type_left);
4384                 return;
4385         }
4386         if(is_type_incomplete(type_left)) {
4387                 errorf(HERE,
4388                        "left-hand side of assignment '%E' has incomplete type '%T'",
4389                        left, orig_type_left);
4390                 return;
4391         }
4392         if(is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
4393                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
4394                        left, orig_type_left);
4395                 return;
4396         }
4397
4398         type_t *const res_type = semantic_assign(orig_type_left, expression->right,
4399                                                  "assignment");
4400         if (res_type == NULL) {
4401                 errorf(expression->expression.source_position,
4402                         "cannot assign to '%T' from '%T'",
4403                         orig_type_left, expression->right->base.datatype);
4404         } else {
4405                 expression->right = create_implicit_cast(expression->right, res_type);
4406         }
4407
4408         expression->expression.datatype = orig_type_left;
4409 }
4410
4411 static void semantic_comma(binary_expression_t *expression)
4412 {
4413         expression->expression.datatype = expression->right->base.datatype;
4414 }
4415
4416 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr)  \
4417 static expression_t *parse_##binexpression_type(unsigned precedence,      \
4418                                                 expression_t *left)       \
4419 {                                                                         \
4420         eat(token_type);                                                      \
4421                                                                           \
4422         expression_t *right = parse_sub_expression(precedence + lr);          \
4423                                                                           \
4424         expression_t *binexpr = allocate_expression_zero(binexpression_type); \
4425         binexpr->binary.left  = left;                                         \
4426         binexpr->binary.right = right;                                        \
4427         sfunc(&binexpr->binary);                                              \
4428                                                                           \
4429         return binexpr;                                                       \
4430 }
4431
4432 CREATE_BINEXPR_PARSER(',', EXPR_BINARY_COMMA,    semantic_comma, 1)
4433 CREATE_BINEXPR_PARSER('*', EXPR_BINARY_MUL,      semantic_binexpr_arithmetic, 1)
4434 CREATE_BINEXPR_PARSER('/', EXPR_BINARY_DIV,      semantic_binexpr_arithmetic, 1)
4435 CREATE_BINEXPR_PARSER('%', EXPR_BINARY_MOD,      semantic_binexpr_arithmetic, 1)
4436 CREATE_BINEXPR_PARSER('+', EXPR_BINARY_ADD,      semantic_add, 1)
4437 CREATE_BINEXPR_PARSER('-', EXPR_BINARY_SUB,      semantic_sub, 1)
4438 CREATE_BINEXPR_PARSER('<', EXPR_BINARY_LESS,     semantic_comparison, 1)
4439 CREATE_BINEXPR_PARSER('>', EXPR_BINARY_GREATER,  semantic_comparison, 1)
4440 CREATE_BINEXPR_PARSER('=', EXPR_BINARY_ASSIGN,   semantic_binexpr_assign, 0)
4441
4442 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,
4443                       semantic_comparison, 1)
4444 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,
4445                       semantic_comparison, 1)
4446 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,
4447                       semantic_comparison, 1)
4448 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,
4449                       semantic_comparison, 1)
4450
4451 CREATE_BINEXPR_PARSER('&', EXPR_BINARY_BITWISE_AND,
4452                       semantic_binexpr_arithmetic, 1)
4453 CREATE_BINEXPR_PARSER('|', EXPR_BINARY_BITWISE_OR,
4454                       semantic_binexpr_arithmetic, 1)
4455 CREATE_BINEXPR_PARSER('^', EXPR_BINARY_BITWISE_XOR,
4456                       semantic_binexpr_arithmetic, 1)
4457 CREATE_BINEXPR_PARSER(T_ANDAND, EXPR_BINARY_LOGICAL_AND,
4458                       semantic_logical_op, 1)
4459 CREATE_BINEXPR_PARSER(T_PIPEPIPE, EXPR_BINARY_LOGICAL_OR,
4460                       semantic_logical_op, 1)
4461 CREATE_BINEXPR_PARSER(T_LESSLESS, EXPR_BINARY_SHIFTLEFT,
4462                       semantic_shift_op, 1)
4463 CREATE_BINEXPR_PARSER(T_GREATERGREATER, EXPR_BINARY_SHIFTRIGHT,
4464                       semantic_shift_op, 1)
4465 CREATE_BINEXPR_PARSER(T_PLUSEQUAL, EXPR_BINARY_ADD_ASSIGN,
4466                       semantic_arithmetic_addsubb_assign, 0)
4467 CREATE_BINEXPR_PARSER(T_MINUSEQUAL, EXPR_BINARY_SUB_ASSIGN,
4468                       semantic_arithmetic_addsubb_assign, 0)
4469 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, EXPR_BINARY_MUL_ASSIGN,
4470                       semantic_arithmetic_assign, 0)
4471 CREATE_BINEXPR_PARSER(T_SLASHEQUAL, EXPR_BINARY_DIV_ASSIGN,
4472                       semantic_arithmetic_assign, 0)
4473 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, EXPR_BINARY_MOD_ASSIGN,
4474                       semantic_arithmetic_assign, 0)
4475 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, EXPR_BINARY_SHIFTLEFT_ASSIGN,
4476                       semantic_arithmetic_assign, 0)
4477 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, EXPR_BINARY_SHIFTRIGHT_ASSIGN,
4478                       semantic_arithmetic_assign, 0)
4479 CREATE_BINEXPR_PARSER(T_ANDEQUAL, EXPR_BINARY_BITWISE_AND_ASSIGN,
4480                       semantic_arithmetic_assign, 0)
4481 CREATE_BINEXPR_PARSER(T_PIPEEQUAL, EXPR_BINARY_BITWISE_OR_ASSIGN,
4482                       semantic_arithmetic_assign, 0)
4483 CREATE_BINEXPR_PARSER(T_CARETEQUAL, EXPR_BINARY_BITWISE_XOR_ASSIGN,
4484                       semantic_arithmetic_assign, 0)
4485
4486 static expression_t *parse_sub_expression(unsigned precedence)
4487 {
4488         if(token.type < 0) {
4489                 return expected_expression_error();
4490         }
4491
4492         expression_parser_function_t *parser
4493                 = &expression_parsers[token.type];
4494         source_position_t             source_position = token.source_position;
4495         expression_t                 *left;
4496
4497         if(parser->parser != NULL) {
4498                 left = parser->parser(parser->precedence);
4499         } else {
4500                 left = parse_primary_expression();
4501         }
4502         assert(left != NULL);
4503         left->base.source_position = source_position;
4504
4505         while(true) {
4506                 if(token.type < 0) {
4507                         return expected_expression_error();
4508                 }
4509
4510                 parser = &expression_parsers[token.type];
4511                 if(parser->infix_parser == NULL)
4512                         break;
4513                 if(parser->infix_precedence < precedence)
4514                         break;
4515
4516                 left = parser->infix_parser(parser->infix_precedence, left);
4517
4518                 assert(left != NULL);
4519                 assert(left->kind != EXPR_UNKNOWN);
4520                 left->base.source_position = source_position;
4521         }
4522
4523         return left;
4524 }
4525
4526 /**
4527  * Parse an expression.
4528  */
4529 static expression_t *parse_expression(void)
4530 {
4531         return parse_sub_expression(1);
4532 }
4533
4534 /**
4535  * Register a parser for a prefix-like operator with given precedence.
4536  *
4537  * @param parser      the parser function
4538  * @param token_type  the token type of the prefix token
4539  * @param precedence  the precedence of the operator
4540  */
4541 static void register_expression_parser(parse_expression_function parser,
4542                                        int token_type, unsigned precedence)
4543 {
4544         expression_parser_function_t *entry = &expression_parsers[token_type];
4545
4546         if(entry->parser != NULL) {
4547                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
4548                 panic("trying to register multiple expression parsers for a token");
4549         }
4550         entry->parser     = parser;
4551         entry->precedence = precedence;
4552 }
4553
4554 /**
4555  * Register a parser for an infix operator with given precedence.
4556  *
4557  * @param parser      the parser function
4558  * @param token_type  the token type of the infix operator
4559  * @param precedence  the precedence of the operator
4560  */
4561 static void register_infix_parser(parse_expression_infix_function parser,
4562                 int token_type, unsigned precedence)
4563 {
4564         expression_parser_function_t *entry = &expression_parsers[token_type];
4565
4566         if(entry->infix_parser != NULL) {
4567                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
4568                 panic("trying to register multiple infix expression parsers for a "
4569                       "token");
4570         }
4571         entry->infix_parser     = parser;
4572         entry->infix_precedence = precedence;
4573 }
4574
4575 /**
4576  * Initialize the expression parsers.
4577  */
4578 static void init_expression_parsers(void)
4579 {
4580         memset(&expression_parsers, 0, sizeof(expression_parsers));
4581
4582         register_infix_parser(parse_array_expression,         '[',              30);
4583         register_infix_parser(parse_call_expression,          '(',              30);
4584         register_infix_parser(parse_select_expression,        '.',              30);
4585         register_infix_parser(parse_select_expression,        T_MINUSGREATER,   30);
4586         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,
4587                                                               T_PLUSPLUS,       30);
4588         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,
4589                                                               T_MINUSMINUS,     30);
4590
4591         register_infix_parser(parse_EXPR_BINARY_MUL,          '*',              16);
4592         register_infix_parser(parse_EXPR_BINARY_DIV,          '/',              16);
4593         register_infix_parser(parse_EXPR_BINARY_MOD,          '%',              16);
4594         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,    T_LESSLESS,       16);
4595         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,   T_GREATERGREATER, 16);
4596         register_infix_parser(parse_EXPR_BINARY_ADD,          '+',              15);
4597         register_infix_parser(parse_EXPR_BINARY_SUB,          '-',              15);
4598         register_infix_parser(parse_EXPR_BINARY_LESS,         '<',              14);
4599         register_infix_parser(parse_EXPR_BINARY_GREATER,      '>',              14);
4600         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,    T_LESSEQUAL,      14);
4601         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL, T_GREATEREQUAL,   14);
4602         register_infix_parser(parse_EXPR_BINARY_EQUAL,        T_EQUALEQUAL,     13);
4603         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,
4604                                                     T_EXCLAMATIONMARKEQUAL, 13);
4605         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,  '&',              12);
4606         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,  '^',              11);
4607         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,   '|',              10);
4608         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,  T_ANDAND,          9);
4609         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,   T_PIPEPIPE,        8);
4610         register_infix_parser(parse_conditional_expression,   '?',               7);
4611         register_infix_parser(parse_EXPR_BINARY_ASSIGN,       '=',               2);
4612         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,   T_PLUSEQUAL,       2);
4613         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,   T_MINUSEQUAL,      2);
4614         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,   T_ASTERISKEQUAL,   2);
4615         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,   T_SLASHEQUAL,      2);
4616         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,   T_PERCENTEQUAL,    2);
4617         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,
4618                                                                 T_LESSLESSEQUAL, 2);
4619         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,
4620                                                           T_GREATERGREATEREQUAL, 2);
4621         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN,
4622                                                                      T_ANDEQUAL, 2);
4623         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,
4624                                                                     T_PIPEEQUAL, 2);
4625         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN,
4626                                                                    T_CARETEQUAL, 2);
4627
4628         register_infix_parser(parse_EXPR_BINARY_COMMA,        ',',               1);
4629
4630         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-',      25);
4631         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+',      25);
4632         register_expression_parser(parse_EXPR_UNARY_NOT,              '!',      25);
4633         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~',      25);
4634         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*',      25);
4635         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&',      25);
4636         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT,
4637                                                                   T_PLUSPLUS,   25);
4638         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT,
4639                                                                   T_MINUSMINUS, 25);
4640         register_expression_parser(parse_sizeof,                  T_sizeof,     25);
4641         register_expression_parser(parse_extension,            T___extension__, 25);
4642         register_expression_parser(parse_builtin_classify_type,
4643                                                      T___builtin_classify_type, 25);
4644 }
4645
4646 /**
4647  * Parse a asm statement constraints specification.
4648  */
4649 static asm_constraint_t *parse_asm_constraints(void)
4650 {
4651         asm_constraint_t *result = NULL;
4652         asm_constraint_t *last   = NULL;
4653
4654         while(token.type == T_STRING_LITERAL || token.type == '[') {
4655                 asm_constraint_t *constraint = allocate_ast_zero(sizeof(constraint[0]));
4656                 memset(constraint, 0, sizeof(constraint[0]));
4657
4658                 if(token.type == '[') {
4659                         eat('[');
4660                         if(token.type != T_IDENTIFIER) {
4661                                 parse_error_expected("while parsing asm constraint",
4662                                                      T_IDENTIFIER, 0);
4663                                 return NULL;
4664                         }
4665                         constraint->symbol = token.v.symbol;
4666
4667                         expect(']');
4668                 }
4669
4670                 constraint->constraints = parse_string_literals();
4671                 expect('(');
4672                 constraint->expression = parse_expression();
4673                 expect(')');
4674
4675                 if(last != NULL) {
4676                         last->next = constraint;
4677                 } else {
4678                         result = constraint;
4679                 }
4680                 last = constraint;
4681
4682                 if(token.type != ',')
4683                         break;
4684                 eat(',');
4685         }
4686
4687         return result;
4688 }
4689
4690 /**
4691  * Parse a asm statement clobber specification.
4692  */
4693 static asm_clobber_t *parse_asm_clobbers(void)
4694 {
4695         asm_clobber_t *result = NULL;
4696         asm_clobber_t *last   = NULL;
4697
4698         while(token.type == T_STRING_LITERAL) {
4699                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
4700                 clobber->clobber       = parse_string_literals();
4701
4702                 if(last != NULL) {
4703                         last->next = clobber;
4704                 } else {
4705                         result = clobber;
4706                 }
4707                 last = clobber;
4708
4709                 if(token.type != ',')
4710                         break;
4711                 eat(',');
4712         }
4713
4714         return result;
4715 }
4716
4717 /**
4718  * Parse an asm statement.
4719  */
4720 static statement_t *parse_asm_statement(void)
4721 {
4722         eat(T_asm);
4723
4724         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
4725         statement->base.source_position = token.source_position;
4726
4727         asm_statement_t *asm_statement = &statement->asms;
4728
4729         if(token.type == T_volatile) {
4730                 next_token();
4731                 asm_statement->is_volatile = true;
4732         }
4733
4734         expect('(');
4735         asm_statement->asm_text = parse_string_literals();
4736
4737         if(token.type != ':')
4738                 goto end_of_asm;
4739         eat(':');
4740
4741         asm_statement->inputs = parse_asm_constraints();
4742         if(token.type != ':')
4743                 goto end_of_asm;
4744         eat(':');
4745
4746         asm_statement->outputs = parse_asm_constraints();
4747         if(token.type != ':')
4748                 goto end_of_asm;
4749         eat(':');
4750
4751         asm_statement->clobbers = parse_asm_clobbers();
4752
4753 end_of_asm:
4754         expect(')');
4755         expect(';');
4756         return statement;
4757 }
4758
4759 /**
4760  * Parse a case statement.
4761  */
4762 static statement_t *parse_case_statement(void)
4763 {
4764         eat(T_case);
4765
4766         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
4767
4768         statement->base.source_position  = token.source_position;
4769         statement->case_label.expression = parse_expression();
4770
4771         expect(':');
4772
4773         if (! is_constant_expression(statement->case_label.expression)) {
4774                 errorf(statement->base.source_position,
4775                         "case label does not reduce to an integer constant");
4776         } else {
4777                 /* TODO: check if the case label is already known */
4778                 if (current_switch != NULL) {
4779                         /* link all cases into the switch statement */
4780                         if (current_switch->last_case == NULL) {
4781                                 current_switch->first_case =
4782                                 current_switch->last_case  = &statement->case_label;
4783                         } else {
4784                                 current_switch->last_case->next = &statement->case_label;
4785                         }
4786                 } else {
4787                         errorf(statement->base.source_position,
4788                                 "case label not within a switch statement");
4789                 }
4790         }
4791         statement->case_label.label_statement = parse_statement();
4792
4793         return statement;
4794 }
4795
4796 /**
4797  * Finds an existing default label of a switch statement.
4798  */
4799 static case_label_statement_t *
4800 find_default_label(const switch_statement_t *statement)
4801 {
4802         for (case_label_statement_t *label = statement->first_case;
4803              label != NULL;
4804                  label = label->next) {
4805                 if (label->expression == NULL)
4806                         return label;
4807         }
4808         return NULL;
4809 }
4810
4811 /**
4812  * Parse a default statement.
4813  */
4814 static statement_t *parse_default_statement(void)
4815 {
4816         eat(T_default);
4817
4818         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
4819
4820         statement->base.source_position = token.source_position;
4821
4822         expect(':');
4823         if (current_switch != NULL) {
4824                 const case_label_statement_t *def_label = find_default_label(current_switch);
4825                 if (def_label != NULL) {
4826                         errorf(HERE, "multiple default labels in one switch");
4827                         errorf(def_label->statement.source_position,
4828                                 "this is the first default label");
4829                 } else {
4830                         /* link all cases into the switch statement */
4831                         if (current_switch->last_case == NULL) {
4832                                 current_switch->first_case =
4833                                         current_switch->last_case  = &statement->case_label;
4834                         } else {
4835                                 current_switch->last_case->next = &statement->case_label;
4836                         }
4837                 }
4838         } else {
4839                 errorf(statement->base.source_position,
4840                         "'default' label not within a switch statement");
4841         }
4842         statement->label.label_statement = parse_statement();
4843
4844         return statement;
4845 }
4846
4847 /**
4848  * Return the declaration for a given label symbol or create a new one.
4849  */
4850 static declaration_t *get_label(symbol_t *symbol)
4851 {
4852         declaration_t *candidate = get_declaration(symbol, NAMESPACE_LABEL);
4853         assert(current_function != NULL);
4854         /* if we found a label in the same function, then we already created the
4855          * declaration */
4856         if(candidate != NULL
4857                         && candidate->parent_context == &current_function->context) {
4858                 return candidate;
4859         }
4860
4861         /* otherwise we need to create a new one */
4862         declaration_t *const declaration = allocate_declaration_zero();
4863         declaration->namespc       = NAMESPACE_LABEL;
4864         declaration->symbol        = symbol;
4865
4866         label_push(declaration);
4867
4868         return declaration;
4869 }
4870
4871 /**
4872  * Parse a label statement.
4873  */
4874 static statement_t *parse_label_statement(void)
4875 {
4876         assert(token.type == T_IDENTIFIER);
4877         symbol_t *symbol = token.v.symbol;
4878         next_token();
4879
4880         declaration_t *label = get_label(symbol);
4881
4882         /* if source position is already set then the label is defined twice,
4883          * otherwise it was just mentioned in a goto so far */
4884         if(label->source_position.input_name != NULL) {
4885                 errorf(HERE, "duplicate label '%Y'", symbol);
4886                 errorf(label->source_position, "previous definition of '%Y' was here",
4887                        symbol);
4888         } else {
4889                 label->source_position = token.source_position;
4890         }
4891
4892         label_statement_t *label_statement = allocate_ast_zero(sizeof(label[0]));
4893
4894         label_statement->statement.kind            = STATEMENT_LABEL;
4895         label_statement->statement.source_position = token.source_position;
4896         label_statement->label                     = label;
4897
4898         eat(':');
4899
4900         if(token.type == '}') {
4901                 /* TODO only warn? */
4902                 errorf(HERE, "label at end of compound statement");
4903                 return (statement_t*) label_statement;
4904         } else {
4905                 label_statement->label_statement = parse_statement();
4906         }
4907
4908         return (statement_t*) label_statement;
4909 }
4910
4911 /**
4912  * Parse an if statement.
4913  */
4914 static statement_t *parse_if(void)
4915 {
4916         eat(T_if);
4917
4918         if_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
4919         statement->statement.kind            = STATEMENT_IF;
4920         statement->statement.source_position = token.source_position;
4921
4922         expect('(');
4923         statement->condition = parse_expression();
4924         expect(')');
4925
4926         statement->true_statement = parse_statement();
4927         if(token.type == T_else) {
4928                 next_token();
4929                 statement->false_statement = parse_statement();
4930         }
4931
4932         return (statement_t*) statement;
4933 }
4934
4935 /**
4936  * Parse a switch statement.
4937  */
4938 static statement_t *parse_switch(void)
4939 {
4940         eat(T_switch);
4941
4942         switch_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
4943         statement->statement.kind            = STATEMENT_SWITCH;
4944         statement->statement.source_position = token.source_position;
4945
4946         expect('(');
4947         expression_t *const expr = parse_expression();
4948         type_t       *      type = skip_typeref(expr->base.datatype);
4949         if (is_type_integer(type)) {
4950                 type = promote_integer(type);
4951         } else if (is_type_valid(type)) {
4952                 errorf(expr->base.source_position, "switch quantity is not an integer, but '%T'", type);
4953                 type = type_error_type;
4954         }
4955         statement->expression = create_implicit_cast(expr, type);
4956         expect(')');
4957
4958         switch_statement_t *rem = current_switch;
4959         current_switch  = statement;
4960         statement->body = parse_statement();
4961         current_switch  = rem;
4962
4963         return (statement_t*) statement;
4964 }
4965
4966 static statement_t *parse_loop_body(statement_t *const loop)
4967 {
4968         statement_t *const rem = current_loop;
4969         current_loop = loop;
4970         statement_t *const body = parse_statement();
4971         current_loop = rem;
4972         return body;
4973 }
4974
4975 /**
4976  * Parse a while statement.
4977  */
4978 static statement_t *parse_while(void)
4979 {
4980         eat(T_while);
4981
4982         while_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
4983         statement->statement.kind            = STATEMENT_WHILE;
4984         statement->statement.source_position = token.source_position;
4985
4986         expect('(');
4987         statement->condition = parse_expression();
4988         expect(')');
4989
4990         statement->body = parse_loop_body((statement_t*)statement);
4991
4992         return (statement_t*) statement;
4993 }
4994
4995 /**
4996  * Parse a do statement.
4997  */
4998 static statement_t *parse_do(void)
4999 {
5000         eat(T_do);
5001
5002         do_while_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
5003         statement->statement.kind            = STATEMENT_DO_WHILE;
5004         statement->statement.source_position = token.source_position;
5005
5006         statement->body = parse_loop_body((statement_t*)statement);
5007         expect(T_while);
5008         expect('(');
5009         statement->condition = parse_expression();
5010         expect(')');
5011         expect(';');
5012
5013         return (statement_t*) statement;
5014 }
5015
5016 /**
5017  * Parse a for statement.
5018  */
5019 static statement_t *parse_for(void)
5020 {
5021         eat(T_for);
5022
5023         for_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
5024         statement->statement.kind            = STATEMENT_FOR;
5025         statement->statement.source_position = token.source_position;
5026
5027         expect('(');
5028
5029         int         top          = environment_top();
5030         context_t  *last_context = context;
5031         set_context(&statement->context);
5032
5033         if(token.type != ';') {
5034                 if(is_declaration_specifier(&token, false)) {
5035                         parse_declaration(record_declaration);
5036                 } else {
5037                         statement->initialisation = parse_expression();
5038                         expect(';');
5039                 }
5040         } else {
5041                 expect(';');
5042         }
5043
5044         if(token.type != ';') {
5045                 statement->condition = parse_expression();
5046         }
5047         expect(';');
5048         if(token.type != ')') {
5049                 statement->step = parse_expression();
5050         }
5051         expect(')');
5052         statement->body = parse_loop_body((statement_t*)statement);
5053
5054         assert(context == &statement->context);
5055         set_context(last_context);
5056         environment_pop_to(top);
5057
5058         return (statement_t*) statement;
5059 }
5060
5061 /**
5062  * Parse a goto statement.
5063  */
5064 static statement_t *parse_goto(void)
5065 {
5066         eat(T_goto);
5067
5068         if(token.type != T_IDENTIFIER) {
5069                 parse_error_expected("while parsing goto", T_IDENTIFIER, 0);
5070                 eat_statement();
5071                 return NULL;
5072         }
5073         symbol_t *symbol = token.v.symbol;
5074         next_token();
5075
5076         declaration_t *label = get_label(symbol);
5077
5078         goto_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
5079
5080         statement->statement.kind            = STATEMENT_GOTO;
5081         statement->statement.source_position = token.source_position;
5082
5083         statement->label = label;
5084
5085         /* remember the goto's in a list for later checking */
5086         if (goto_last == NULL) {
5087                 goto_first = goto_last = statement;
5088         } else {
5089                 goto_last->next = statement;
5090         }
5091
5092         expect(';');
5093
5094         return (statement_t*) statement;
5095 }
5096
5097 /**
5098  * Parse a continue statement.
5099  */
5100 static statement_t *parse_continue(void)
5101 {
5102         statement_t *statement;
5103         if (current_loop == NULL) {
5104                 errorf(HERE, "continue statement not within loop");
5105                 statement = NULL;
5106         } else {
5107                 statement = allocate_statement_zero(STATEMENT_CONTINUE);
5108
5109                 statement->base.source_position = token.source_position;
5110         }
5111
5112         eat(T_continue);
5113         expect(';');
5114
5115         return statement;
5116 }
5117
5118 /**
5119  * Parse a break statement.
5120  */
5121 static statement_t *parse_break(void)
5122 {
5123         statement_t *statement;
5124         if (current_switch == NULL && current_loop == NULL) {
5125                 errorf(HERE, "break statement not within loop or switch");
5126                 statement = NULL;
5127         } else {
5128                 statement = allocate_statement_zero(STATEMENT_BREAK);
5129
5130                 statement->base.source_position = token.source_position;
5131         }
5132
5133         eat(T_break);
5134         expect(';');
5135
5136         return statement;
5137 }
5138
5139 /**
5140  * Check if a given declaration represents a local variable.
5141  */
5142 static bool is_local_var_declaration(const declaration_t *declaration) {
5143         switch ((storage_class_tag_t) declaration->storage_class) {
5144         case STORAGE_CLASS_NONE:
5145         case STORAGE_CLASS_AUTO:
5146         case STORAGE_CLASS_REGISTER: {
5147                 const type_t *type = skip_typeref(declaration->type);
5148                 if(is_type_function(type)) {
5149                         return false;
5150                 } else {
5151                         return true;
5152                 }
5153         }
5154         default:
5155                 return false;
5156         }
5157 }
5158
5159 /**
5160  * Check if a given expression represents a local variable.
5161  */
5162 static bool is_local_variable(const expression_t *expression)
5163 {
5164         if (expression->base.kind != EXPR_REFERENCE) {
5165                 return false;
5166         }
5167         const declaration_t *declaration = expression->reference.declaration;
5168         return is_local_var_declaration(declaration);
5169 }
5170
5171 /**
5172  * Parse a return statement.
5173  */
5174 static statement_t *parse_return(void)
5175 {
5176         eat(T_return);
5177
5178         return_statement_t *statement = allocate_ast_zero(sizeof(statement[0]));
5179
5180         statement->statement.kind            = STATEMENT_RETURN;
5181         statement->statement.source_position = token.source_position;
5182
5183         expression_t *return_value = NULL;
5184         if(token.type != ';') {
5185                 return_value = parse_expression();
5186         }
5187         expect(';');
5188
5189         const type_t *const func_type = current_function->type;
5190         assert(is_type_function(func_type));
5191         type_t *const return_type = skip_typeref(func_type->function.return_type);
5192
5193         if(return_value != NULL) {
5194                 type_t *return_value_type = skip_typeref(return_value->base.datatype);
5195
5196                 if(is_type_atomic(return_type, ATOMIC_TYPE_VOID)
5197                                 && !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
5198                         warningf(statement->statement.source_position,
5199                                 "'return' with a value, in function returning void");
5200                         return_value = NULL;
5201                 } else {
5202                         type_t *const res_type = semantic_assign(return_type,
5203                                 return_value, "'return'");
5204                         if (res_type == NULL) {
5205                                 errorf(statement->statement.source_position,
5206                                         "cannot return something of type '%T' in function returning '%T'",
5207                                         return_value->base.datatype, return_type);
5208                         } else {
5209                                 return_value = create_implicit_cast(return_value, res_type);
5210                         }
5211                 }
5212                 /* check for returning address of a local var */
5213                 if (return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
5214                         const expression_t *expression = return_value->unary.value;
5215                         if (is_local_variable(expression)) {
5216                                 warningf(statement->statement.source_position,
5217                                         "function returns address of local variable");
5218                         }
5219                 }
5220         } else {
5221                 if(!is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
5222                         warningf(statement->statement.source_position,
5223                                 "'return' without value, in function returning non-void");
5224                 }
5225         }
5226         statement->return_value = return_value;
5227
5228         return (statement_t*) statement;
5229 }
5230
5231 /**
5232  * Parse a declaration statement.
5233  */
5234 static statement_t *parse_declaration_statement(void)
5235 {
5236         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
5237
5238         statement->base.source_position = token.source_position;
5239
5240         declaration_t *before = last_declaration;
5241         parse_declaration(record_declaration);
5242
5243         if(before == NULL) {
5244                 statement->declaration.declarations_begin = context->declarations;
5245         } else {
5246                 statement->declaration.declarations_begin = before->next;
5247         }
5248         statement->declaration.declarations_end = last_declaration;
5249
5250         return statement;
5251 }
5252
5253 /**
5254  * Parse an expression statement, ie. expr ';'.
5255  */
5256 static statement_t *parse_expression_statement(void)
5257 {
5258         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
5259
5260         statement->base.source_position  = token.source_position;
5261         statement->expression.expression = parse_expression();
5262
5263         expect(';');
5264
5265         return statement;
5266 }
5267
5268 /**
5269  * Parse a statement.
5270  */
5271 static statement_t *parse_statement(void)
5272 {
5273         statement_t   *statement = NULL;
5274
5275         /* declaration or statement */
5276         switch(token.type) {
5277         case T_asm:
5278                 statement = parse_asm_statement();
5279                 break;
5280
5281         case T_case:
5282                 statement = parse_case_statement();
5283                 break;
5284
5285         case T_default:
5286                 statement = parse_default_statement();
5287                 break;
5288
5289         case '{':
5290                 statement = parse_compound_statement();
5291                 break;
5292
5293         case T_if:
5294                 statement = parse_if();
5295                 break;
5296
5297         case T_switch:
5298                 statement = parse_switch();
5299                 break;
5300
5301         case T_while:
5302                 statement = parse_while();
5303                 break;
5304
5305         case T_do:
5306                 statement = parse_do();
5307                 break;
5308
5309         case T_for:
5310                 statement = parse_for();
5311                 break;
5312
5313         case T_goto:
5314                 statement = parse_goto();
5315                 break;
5316
5317         case T_continue:
5318                 statement = parse_continue();
5319                 break;
5320
5321         case T_break:
5322                 statement = parse_break();
5323                 break;
5324
5325         case T_return:
5326                 statement = parse_return();
5327                 break;
5328
5329         case ';':
5330                 next_token();
5331                 statement = NULL;
5332                 break;
5333
5334         case T_IDENTIFIER:
5335                 if(look_ahead(1)->type == ':') {
5336                         statement = parse_label_statement();
5337                         break;
5338                 }
5339
5340                 if(is_typedef_symbol(token.v.symbol)) {
5341                         statement = parse_declaration_statement();
5342                         break;
5343                 }
5344
5345                 statement = parse_expression_statement();
5346                 break;
5347
5348         case T___extension__:
5349                 /* this can be a prefix to a declaration or an expression statement */
5350                 /* we simply eat it now and parse the rest with tail recursion */
5351                 do {
5352                         next_token();
5353                 } while(token.type == T___extension__);
5354                 statement = parse_statement();
5355                 break;
5356
5357         DECLARATION_START
5358                 statement = parse_declaration_statement();
5359                 break;
5360
5361         default:
5362                 statement = parse_expression_statement();
5363                 break;
5364         }
5365
5366         assert(statement == NULL
5367                         || statement->base.source_position.input_name != NULL);
5368
5369         return statement;
5370 }
5371
5372 /**
5373  * Parse a compound statement.
5374  */
5375 static statement_t *parse_compound_statement(void)
5376 {
5377         compound_statement_t *const compound_statement
5378                 = allocate_ast_zero(sizeof(compound_statement[0]));
5379         compound_statement->statement.kind            = STATEMENT_COMPOUND;
5380         compound_statement->statement.source_position = token.source_position;
5381
5382         eat('{');
5383
5384         int        top          = environment_top();
5385         context_t *last_context = context;
5386         set_context(&compound_statement->context);
5387
5388         statement_t *last_statement = NULL;
5389
5390         while(token.type != '}' && token.type != T_EOF) {
5391                 statement_t *statement = parse_statement();
5392                 if(statement == NULL)
5393                         continue;
5394
5395                 if(last_statement != NULL) {
5396                         last_statement->base.next = statement;
5397                 } else {
5398                         compound_statement->statements = statement;
5399                 }
5400
5401                 while(statement->base.next != NULL)
5402                         statement = statement->base.next;
5403
5404                 last_statement = statement;
5405         }
5406
5407         if(token.type == '}') {
5408                 next_token();
5409         } else {
5410                 errorf(compound_statement->statement.source_position, "end of file while looking for closing '}'");
5411         }
5412
5413         assert(context == &compound_statement->context);
5414         set_context(last_context);
5415         environment_pop_to(top);
5416
5417         return (statement_t*) compound_statement;
5418 }
5419
5420 /**
5421  * Initialize builtin types.
5422  */
5423 static void initialize_builtin_types(void)
5424 {
5425         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
5426         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
5427         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
5428         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
5429         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
5430         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
5431         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    type_int);
5432         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
5433
5434         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
5435         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
5436         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
5437         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
5438 }
5439
5440 /**
5441  * Parse a translation unit.
5442  */
5443 static translation_unit_t *parse_translation_unit(void)
5444 {
5445         translation_unit_t *unit = allocate_ast_zero(sizeof(unit[0]));
5446
5447         assert(global_context == NULL);
5448         global_context = &unit->context;
5449
5450         assert(context == NULL);
5451         set_context(&unit->context);
5452
5453         initialize_builtin_types();
5454
5455         while(token.type != T_EOF) {
5456                 if (token.type == ';') {
5457                         /* TODO error in strict mode */
5458                         warningf(HERE, "stray ';' outside of function");
5459                         next_token();
5460                 } else {
5461                         parse_external_declaration();
5462                 }
5463         }
5464
5465         assert(context == &unit->context);
5466         context          = NULL;
5467         last_declaration = NULL;
5468
5469         assert(global_context == &unit->context);
5470         global_context = NULL;
5471
5472         return unit;
5473 }
5474
5475 /**
5476  * Parse the input.
5477  *
5478  * @return  the translation unit or NULL if errors occurred.
5479  */
5480 translation_unit_t *parse(void)
5481 {
5482         environment_stack = NEW_ARR_F(stack_entry_t, 0);
5483         label_stack       = NEW_ARR_F(stack_entry_t, 0);
5484         diagnostic_count  = 0;
5485         error_count       = 0;
5486         warning_count     = 0;
5487
5488         type_set_output(stderr);
5489         ast_set_output(stderr);
5490
5491         lookahead_bufpos = 0;
5492         for(int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
5493                 next_token();
5494         }
5495         translation_unit_t *unit = parse_translation_unit();
5496
5497         DEL_ARR_F(environment_stack);
5498         DEL_ARR_F(label_stack);
5499
5500         if(error_count > 0)
5501                 return NULL;
5502
5503         return unit;
5504 }
5505
5506 /**
5507  * Initialize the parser.
5508  */
5509 void init_parser(void)
5510 {
5511         init_expression_parsers();
5512         obstack_init(&temp_obst);
5513
5514         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
5515         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
5516 }
5517
5518 /**
5519  * Terminate the parser.
5520  */
5521 void exit_parser(void)
5522 {
5523         obstack_free(&temp_obst, NULL);
5524 }