nsz Git - cparser/blob - parser.c

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