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 int 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
3058         specifiers->source_position = token.source_position;
3059
3060         while (true) {
3061                 specifiers->modifiers
3062                         |= parse_attributes(&specifiers->gnu_attributes);
3063                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3064                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3065
3066                 switch(token.type) {
3067
3068                 /* storage class */
3069 #define MATCH_STORAGE_CLASS(token, class)                                  \
3070                 case token:                                                        \
3071                         if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) { \
3072                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3073                         }                                                              \
3074                         specifiers->declared_storage_class = class;                    \
3075                         next_token();                                                  \
3076                         break;
3077
3078                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3079                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3080                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3081                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3082                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3083
3084                 case T__declspec:
3085                         next_token();
3086                         expect('(');
3087                         add_anchor_token(')');
3088                         parse_microsoft_extended_decl_modifier(specifiers);
3089                         rem_anchor_token(')');
3090                         expect(')');
3091                         break;
3092
3093                 case T___thread:
3094                         switch (specifiers->declared_storage_class) {
3095                         case STORAGE_CLASS_NONE:
3096                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD;
3097                                 break;
3098
3099                         case STORAGE_CLASS_EXTERN:
3100                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_EXTERN;
3101                                 break;
3102
3103                         case STORAGE_CLASS_STATIC:
3104                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_STATIC;
3105                                 break;
3106
3107                         default:
3108                                 errorf(HERE, "multiple storage classes in declaration specifiers");
3109                                 break;
3110                         }
3111                         next_token();
3112                         break;
3113
3114                 /* type qualifiers */
3115 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3116                 case token:                                                     \
3117                         qualifiers |= qualifier;                                    \
3118                         next_token();                                               \
3119                         break
3120
3121                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3122                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3123                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3124                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3125                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3126                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3127                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3128                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3129
3130                 case T___extension__:
3131                         /* TODO */
3132                         next_token();
3133                         break;
3134
3135                 /* type specifiers */
3136 #define MATCH_SPECIFIER(token, specifier, name)                         \
3137                 case token:                                                     \
3138                         next_token();                                               \
3139                         if (type_specifiers & specifier) {                           \
3140                                 errorf(HERE, "multiple " name " type specifiers given"); \
3141                         } else {                                                    \
3142                                 type_specifiers |= specifier;                           \
3143                         }                                                           \
3144                         break
3145
3146                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3147                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3148                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3149                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3150                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3151                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3152                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3153                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3154                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3155                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3156                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3157                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3158                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3159                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3160                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3161                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3162
3163                 case T__forceinline:
3164                         /* only in microsoft mode */
3165                         specifiers->modifiers |= DM_FORCEINLINE;
3166                         /* FALLTHROUGH */
3167
3168                 case T_inline:
3169                         next_token();
3170                         specifiers->is_inline = true;
3171                         break;
3172
3173                 case T_long:
3174                         next_token();
3175                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3176                                 errorf(HERE, "multiple type specifiers given");
3177                         } else if (type_specifiers & SPECIFIER_LONG) {
3178                                 type_specifiers |= SPECIFIER_LONG_LONG;
3179                         } else {
3180                                 type_specifiers |= SPECIFIER_LONG;
3181                         }
3182                         break;
3183
3184                 case T_struct: {
3185                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT, HERE);
3186
3187                         type->compound.declaration = parse_compound_type_specifier(true);
3188                         break;
3189                 }
3190                 case T_union: {
3191                         type = allocate_type_zero(TYPE_COMPOUND_UNION, HERE);
3192                         type->compound.declaration = parse_compound_type_specifier(false);
3193                         if (type->compound.declaration->modifiers & DM_TRANSPARENT_UNION)
3194                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3195                         break;
3196                 }
3197                 case T_enum:
3198                         type = parse_enum_specifier();
3199                         break;
3200                 case T___typeof__:
3201                         type = parse_typeof();
3202                         break;
3203                 case T___builtin_va_list:
3204                         type = duplicate_type(type_valist);
3205                         next_token();
3206                         break;
3207
3208                 case T_IDENTIFIER: {
3209                         /* only parse identifier if we haven't found a type yet */
3210                         if (type != NULL || type_specifiers != 0)
3211                                 goto finish_specifiers;
3212
3213                         type_t *typedef_type = get_typedef_type(token.v.symbol);
3214
3215                         if (typedef_type == NULL)
3216                                 goto finish_specifiers;
3217
3218                         next_token();
3219                         type = typedef_type;
3220                         break;
3221                 }
3222
3223                 /* function specifier */
3224                 default:
3225                         goto finish_specifiers;
3226                 }
3227         }
3228
3229 finish_specifiers:
3230
3231         if (type == NULL) {
3232                 atomic_type_kind_t atomic_type;
3233
3234                 /* match valid basic types */
3235                 switch(type_specifiers) {
3236                 case SPECIFIER_VOID:
3237                         atomic_type = ATOMIC_TYPE_VOID;
3238                         break;
3239                 case SPECIFIER_CHAR:
3240                         atomic_type = ATOMIC_TYPE_CHAR;
3241                         break;
3242                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3243                         atomic_type = ATOMIC_TYPE_SCHAR;
3244                         break;
3245                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3246                         atomic_type = ATOMIC_TYPE_UCHAR;
3247                         break;
3248                 case SPECIFIER_SHORT:
3249                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3250                 case SPECIFIER_SHORT | SPECIFIER_INT:
3251                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3252                         atomic_type = ATOMIC_TYPE_SHORT;
3253                         break;
3254                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3255                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3256                         atomic_type = ATOMIC_TYPE_USHORT;
3257                         break;
3258                 case SPECIFIER_INT:
3259                 case SPECIFIER_SIGNED:
3260                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3261                         atomic_type = ATOMIC_TYPE_INT;
3262                         break;
3263                 case SPECIFIER_UNSIGNED:
3264                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3265                         atomic_type = ATOMIC_TYPE_UINT;
3266                         break;
3267                 case SPECIFIER_LONG:
3268                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3269                 case SPECIFIER_LONG | SPECIFIER_INT:
3270                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3271                         atomic_type = ATOMIC_TYPE_LONG;
3272                         break;
3273                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3274                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3275                         atomic_type = ATOMIC_TYPE_ULONG;
3276                         break;
3277
3278                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3279                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3280                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3281                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3282                         | SPECIFIER_INT:
3283                         atomic_type = ATOMIC_TYPE_LONGLONG;
3284                         goto warn_about_long_long;
3285
3286                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3287                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3288                         | SPECIFIER_INT:
3289                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3290 warn_about_long_long:
3291                         if (warning.long_long) {
3292                                 warningf(&specifiers->source_position,
3293                                          "ISO C90 does not support 'long long'");
3294                         }
3295                         break;
3296
3297                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3298                         atomic_type = unsigned_int8_type_kind;
3299                         break;
3300
3301                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3302                         atomic_type = unsigned_int16_type_kind;
3303                         break;
3304
3305                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3306                         atomic_type = unsigned_int32_type_kind;
3307                         break;
3308
3309                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3310                         atomic_type = unsigned_int64_type_kind;
3311                         break;
3312
3313                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3314                         atomic_type = unsigned_int128_type_kind;
3315                         break;
3316
3317                 case SPECIFIER_INT8:
3318                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3319                         atomic_type = int8_type_kind;
3320                         break;
3321
3322                 case SPECIFIER_INT16:
3323                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3324                         atomic_type = int16_type_kind;
3325                         break;
3326
3327                 case SPECIFIER_INT32:
3328                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3329                         atomic_type = int32_type_kind;
3330                         break;
3331
3332                 case SPECIFIER_INT64:
3333                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3334                         atomic_type = int64_type_kind;
3335                         break;
3336
3337                 case SPECIFIER_INT128:
3338                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3339                         atomic_type = int128_type_kind;
3340                         break;
3341
3342                 case SPECIFIER_FLOAT:
3343                         atomic_type = ATOMIC_TYPE_FLOAT;
3344                         break;
3345                 case SPECIFIER_DOUBLE:
3346                         atomic_type = ATOMIC_TYPE_DOUBLE;
3347                         break;
3348                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3349                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3350                         break;
3351                 case SPECIFIER_BOOL:
3352                         atomic_type = ATOMIC_TYPE_BOOL;
3353                         break;
3354                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3355                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3356                         atomic_type = ATOMIC_TYPE_FLOAT;
3357                         break;
3358                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3359                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3360                         atomic_type = ATOMIC_TYPE_DOUBLE;
3361                         break;
3362                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3363                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3364                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3365                         break;
3366                 default:
3367                         /* invalid specifier combination, give an error message */
3368                         if (type_specifiers == 0) {
3369                                 if (! strict_mode) {
3370                                         if (warning.implicit_int) {
3371                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3372                                         }
3373                                         atomic_type = ATOMIC_TYPE_INT;
3374                                         break;
3375                                 } else {
3376                                         errorf(HERE, "no type specifiers given in declaration");
3377                                 }
3378                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3379                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3380                                 errorf(HERE, "signed and unsigned specifiers given");
3381                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3382                                 errorf(HERE, "only integer types can be signed or unsigned");
3383                         } else {
3384                                 errorf(HERE, "multiple datatypes in declaration");
3385                         }
3386                         atomic_type = ATOMIC_TYPE_INVALID;
3387                 }
3388
3389                 if (type_specifiers & SPECIFIER_COMPLEX &&
3390                    atomic_type != ATOMIC_TYPE_INVALID) {
3391                         type                = allocate_type_zero(TYPE_COMPLEX, &builtin_source_position);
3392                         type->complex.akind = atomic_type;
3393                 } else if (type_specifiers & SPECIFIER_IMAGINARY &&
3394                           atomic_type != ATOMIC_TYPE_INVALID) {
3395                         type                  = allocate_type_zero(TYPE_IMAGINARY, &builtin_source_position);
3396                         type->imaginary.akind = atomic_type;
3397                 } else {
3398                         type               = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
3399                         type->atomic.akind = atomic_type;
3400                 }
3401                 newtype = true;
3402         } else if (type_specifiers != 0) {
3403                 errorf(HERE, "multiple datatypes in declaration");
3404         }
3405
3406         /* FIXME: check type qualifiers here */
3407
3408         type->base.qualifiers = qualifiers;
3409         type->base.modifiers  = modifiers;
3410
3411         type_t *result = typehash_insert(type);
3412         if (newtype && result != type) {
3413                 free_type(type);
3414         }
3415
3416         specifiers->type = result;
3417 end_error:
3418         return;
3419 }
3420
3421 static type_qualifiers_t parse_type_qualifiers(void)
3422 {
3423         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3424
3425         while (true) {
3426                 switch(token.type) {
3427                 /* type qualifiers */
3428                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3429                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3430                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3431                 /* microsoft extended type modifiers */
3432                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3433                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3434                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3435                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3436                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3437
3438                 default:
3439                         return qualifiers;
3440                 }
3441         }
3442 }
3443
3444 static declaration_t *parse_identifier_list(void)
3445 {
3446         declaration_t *declarations     = NULL;
3447         declaration_t *last_declaration = NULL;
3448         do {
3449                 declaration_t *const declaration = allocate_declaration_zero();
3450                 declaration->type            = NULL; /* a K&R parameter list has no types, yet */
3451                 declaration->source_position = token.source_position;
3452                 declaration->symbol          = token.v.symbol;
3453                 next_token();
3454
3455                 if (last_declaration != NULL) {
3456                         last_declaration->next = declaration;
3457                 } else {
3458                         declarations = declaration;
3459                 }
3460                 last_declaration = declaration;
3461
3462                 if (token.type != ',') {
3463                         break;
3464                 }
3465                 next_token();
3466         } while (token.type == T_IDENTIFIER);
3467
3468         return declarations;
3469 }
3470
3471 static type_t *automatic_type_conversion(type_t *orig_type);
3472
3473 static void semantic_parameter(declaration_t *declaration)
3474 {
3475         /* TODO: improve error messages */
3476         source_position_t const* const pos = &declaration->source_position;
3477
3478         switch (declaration->declared_storage_class) {
3479                 case STORAGE_CLASS_TYPEDEF:
3480                         errorf(pos, "typedef not allowed in parameter list");
3481                         break;
3482
3483                 /* Allowed storage classes */
3484                 case STORAGE_CLASS_NONE:
3485                 case STORAGE_CLASS_REGISTER:
3486                         break;
3487
3488                 default:
3489                         errorf(pos, "parameter may only have none or register storage class");
3490                         break;
3491         }
3492
3493         type_t *const orig_type = declaration->type;
3494         /* §6.7.5.3(7): Array as last part of a parameter type is just syntactic
3495          * sugar.  Turn it into a pointer.
3496          * §6.7.5.3(8): A declaration of a parameter as ``function returning type''
3497          * shall be adjusted to ``pointer to function returning type'', as in 6.3.2.1.
3498          */
3499         type_t *const type = automatic_type_conversion(orig_type);
3500         declaration->type = type;
3501
3502         if (is_type_incomplete(skip_typeref(type))) {
3503                 errorf(pos, "incomplete type '%T' not allowed for parameter '%Y'",
3504                        orig_type, declaration->symbol);
3505         }
3506 }
3507
3508 static declaration_t *parse_parameter(void)
3509 {
3510         declaration_specifiers_t specifiers;
3511         memset(&specifiers, 0, sizeof(specifiers));
3512
3513         parse_declaration_specifiers(&specifiers);
3514
3515         declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/true);
3516
3517         return declaration;
3518 }
3519
3520 static declaration_t *parse_parameters(function_type_t *type)
3521 {
3522         declaration_t *declarations = NULL;
3523
3524         eat('(');
3525         add_anchor_token(')');
3526         int saved_comma_state = save_and_reset_anchor_state(',');
3527
3528         if (token.type == T_IDENTIFIER) {
3529                 symbol_t *symbol = token.v.symbol;
3530                 if (!is_typedef_symbol(symbol)) {
3531                         type->kr_style_parameters = true;
3532                         declarations = parse_identifier_list();
3533                         goto parameters_finished;
3534                 }
3535         }
3536
3537         if (token.type == ')') {
3538                 type->unspecified_parameters = 1;
3539                 goto parameters_finished;
3540         }
3541
3542         declaration_t        *declaration;
3543         declaration_t        *last_declaration = NULL;
3544         function_parameter_t *parameter;
3545         function_parameter_t *last_parameter = NULL;
3546
3547         while (true) {
3548                 switch(token.type) {
3549                 case T_DOTDOTDOT:
3550                         next_token();
3551                         type->variadic = 1;
3552                         goto parameters_finished;
3553
3554                 case T_IDENTIFIER:
3555                 case T___extension__:
3556                 DECLARATION_START
3557                         declaration = parse_parameter();
3558
3559                         /* func(void) is not a parameter */
3560                         if (last_parameter == NULL
3561                                         && token.type == ')'
3562                                         && declaration->symbol == NULL
3563                                         && skip_typeref(declaration->type) == type_void) {
3564                                 goto parameters_finished;
3565                         }
3566                         semantic_parameter(declaration);
3567
3568                         parameter       = obstack_alloc(type_obst, sizeof(parameter[0]));
3569                         memset(parameter, 0, sizeof(parameter[0]));
3570                         parameter->type = declaration->type;
3571
3572                         if (last_parameter != NULL) {
3573                                 last_declaration->next = declaration;
3574                                 last_parameter->next   = parameter;
3575                         } else {
3576                                 type->parameters = parameter;
3577                                 declarations     = declaration;
3578                         }
3579                         last_parameter   = parameter;
3580                         last_declaration = declaration;
3581                         break;
3582
3583                 default:
3584                         goto parameters_finished;
3585                 }
3586                 if (token.type != ',') {
3587                         goto parameters_finished;
3588                 }
3589                 next_token();
3590         }
3591
3592
3593 parameters_finished:
3594         rem_anchor_token(')');
3595         expect(')');
3596
3597         restore_anchor_state(',', saved_comma_state);
3598         return declarations;
3599
3600 end_error:
3601         restore_anchor_state(',', saved_comma_state);
3602         return NULL;
3603 }
3604
3605 typedef enum construct_type_kind_t {
3606         CONSTRUCT_INVALID,
3607         CONSTRUCT_POINTER,
3608         CONSTRUCT_FUNCTION,
3609         CONSTRUCT_ARRAY
3610 } construct_type_kind_t;
3611
3612 typedef struct construct_type_t construct_type_t;
3613 struct construct_type_t {
3614         construct_type_kind_t  kind;
3615         construct_type_t      *next;
3616 };
3617
3618 typedef struct parsed_pointer_t parsed_pointer_t;
3619 struct parsed_pointer_t {
3620         construct_type_t  construct_type;
3621         type_qualifiers_t type_qualifiers;
3622 };
3623
3624 typedef struct construct_function_type_t construct_function_type_t;
3625 struct construct_function_type_t {
3626         construct_type_t  construct_type;
3627         type_t           *function_type;
3628 };
3629
3630 typedef struct parsed_array_t parsed_array_t;
3631 struct parsed_array_t {
3632         construct_type_t  construct_type;
3633         type_qualifiers_t type_qualifiers;
3634         bool              is_static;
3635         bool              is_variable;
3636         expression_t     *size;
3637 };
3638
3639 typedef struct construct_base_type_t construct_base_type_t;
3640 struct construct_base_type_t {
3641         construct_type_t  construct_type;
3642         type_t           *type;
3643 };
3644
3645 static construct_type_t *parse_pointer_declarator(void)
3646 {
3647         eat('*');
3648
3649         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
3650         memset(pointer, 0, sizeof(pointer[0]));
3651         pointer->construct_type.kind = CONSTRUCT_POINTER;
3652         pointer->type_qualifiers     = parse_type_qualifiers();
3653
3654         return (construct_type_t*) pointer;
3655 }
3656
3657 static construct_type_t *parse_array_declarator(void)
3658 {
3659         eat('[');
3660         add_anchor_token(']');
3661
3662         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
3663         memset(array, 0, sizeof(array[0]));
3664         array->construct_type.kind = CONSTRUCT_ARRAY;
3665
3666         if (token.type == T_static) {
3667                 array->is_static = true;
3668                 next_token();
3669         }
3670
3671         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
3672         if (type_qualifiers != 0) {
3673                 if (token.type == T_static) {
3674                         array->is_static = true;
3675                         next_token();
3676                 }
3677         }
3678         array->type_qualifiers = type_qualifiers;
3679
3680         if (token.type == '*' && look_ahead(1)->type == ']') {
3681                 array->is_variable = true;
3682                 next_token();
3683         } else if (token.type != ']') {
3684                 array->size = parse_assignment_expression();
3685         }
3686
3687         rem_anchor_token(']');
3688         expect(']');
3689
3690         return (construct_type_t*) array;
3691 end_error:
3692         return NULL;
3693 }
3694
3695 static construct_type_t *parse_function_declarator(declaration_t *declaration)
3696 {
3697         type_t *type;
3698         if (declaration != NULL) {
3699                 type = allocate_type_zero(TYPE_FUNCTION, &declaration->source_position);
3700
3701                 unsigned mask = declaration->modifiers & (DM_CDECL|DM_STDCALL|DM_FASTCALL|DM_THISCALL);
3702
3703                 if (mask & (mask-1)) {
3704                         const char *first = NULL, *second = NULL;
3705
3706                         /* more than one calling convention set */
3707                         if (declaration->modifiers & DM_CDECL) {
3708                                 if (first == NULL)       first = "cdecl";
3709                                 else if (second == NULL) second = "cdecl";
3710                         }
3711                         if (declaration->modifiers & DM_STDCALL) {
3712                                 if (first == NULL)       first = "stdcall";
3713                                 else if (second == NULL) second = "stdcall";
3714                         }
3715                         if (declaration->modifiers & DM_FASTCALL) {
3716                                 if (first == NULL)       first = "fastcall";
3717                                 else if (second == NULL) second = "fastcall";
3718                         }
3719                         if (declaration->modifiers & DM_THISCALL) {
3720                                 if (first == NULL)       first = "thiscall";
3721                                 else if (second == NULL) second = "thiscall";
3722                         }
3723                         errorf(&declaration->source_position, "%s and %s attributes are not compatible", first, second);
3724                 }
3725
3726                 if (declaration->modifiers & DM_CDECL)
3727                         type->function.calling_convention = CC_CDECL;
3728                 else if (declaration->modifiers & DM_STDCALL)
3729                         type->function.calling_convention = CC_STDCALL;
3730                 else if (declaration->modifiers & DM_FASTCALL)
3731                         type->function.calling_convention = CC_FASTCALL;
3732                 else if (declaration->modifiers & DM_THISCALL)
3733                         type->function.calling_convention = CC_THISCALL;
3734         } else {
3735                 type = allocate_type_zero(TYPE_FUNCTION, HERE);
3736         }
3737
3738         declaration_t *parameters = parse_parameters(&type->function);
3739         if (declaration != NULL) {
3740                 declaration->scope.declarations = parameters;
3741         }
3742
3743         construct_function_type_t *construct_function_type =
3744                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
3745         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
3746         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
3747         construct_function_type->function_type       = type;
3748
3749         return &construct_function_type->construct_type;
3750 }
3751
3752 static void fix_declaration_type(declaration_t *declaration)
3753 {
3754         decl_modifiers_t declaration_modifiers = declaration->modifiers;
3755         type_modifiers_t type_modifiers        = declaration->type->base.modifiers;
3756
3757         if (declaration_modifiers & DM_TRANSPARENT_UNION)
3758                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3759
3760         if (declaration->type->base.modifiers == type_modifiers)
3761                 return;
3762
3763         type_t *copy = duplicate_type(declaration->type);
3764         copy->base.modifiers = type_modifiers;
3765
3766         type_t *result = typehash_insert(copy);
3767         if (result != copy) {
3768                 obstack_free(type_obst, copy);
3769         }
3770
3771         declaration->type = result;
3772 }
3773
3774 static construct_type_t *parse_inner_declarator(declaration_t *declaration,
3775                 bool may_be_abstract)
3776 {
3777         /* construct a single linked list of construct_type_t's which describe
3778          * how to construct the final declarator type */
3779         construct_type_t *first = NULL;
3780         construct_type_t *last  = NULL;
3781         gnu_attribute_t  *attributes = NULL;
3782
3783         decl_modifiers_t modifiers = parse_attributes(&attributes);
3784
3785         /* pointers */
3786         while (token.type == '*') {
3787                 construct_type_t *type = parse_pointer_declarator();
3788
3789                 if (last == NULL) {
3790                         first = type;
3791                         last  = type;
3792                 } else {
3793                         last->next = type;
3794                         last       = type;
3795                 }
3796
3797                 /* TODO: find out if this is correct */
3798                 modifiers |= parse_attributes(&attributes);
3799         }
3800
3801         if (declaration != NULL)
3802                 declaration->modifiers |= modifiers;
3803
3804         construct_type_t *inner_types = NULL;
3805
3806         switch(token.type) {
3807         case T_IDENTIFIER:
3808                 if (declaration == NULL) {
3809                         errorf(HERE, "no identifier expected in typename");
3810                 } else {
3811                         declaration->symbol          = token.v.symbol;
3812                         declaration->source_position = token.source_position;
3813                 }
3814                 next_token();
3815                 break;
3816         case '(':
3817                 next_token();
3818                 add_anchor_token(')');
3819                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
3820                 /* All later declarators only modify the return type, not declaration */
3821                 declaration = NULL;
3822                 rem_anchor_token(')');
3823                 expect(')');
3824                 break;
3825         default:
3826                 if (may_be_abstract)
3827                         break;
3828                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
3829                 /* avoid a loop in the outermost scope, because eat_statement doesn't
3830                  * eat '}' */
3831                 if (token.type == '}' && current_function == NULL) {
3832                         next_token();
3833                 } else {
3834                         eat_statement();
3835                 }
3836                 return NULL;
3837         }
3838
3839         construct_type_t *p = last;
3840
3841         while(true) {
3842                 construct_type_t *type;
3843                 switch(token.type) {
3844                 case '(':
3845                         type = parse_function_declarator(declaration);
3846                         break;
3847                 case '[':
3848                         type = parse_array_declarator();
3849                         break;
3850                 default:
3851                         goto declarator_finished;
3852                 }
3853
3854                 /* insert in the middle of the list (behind p) */
3855                 if (p != NULL) {
3856                         type->next = p->next;
3857                         p->next    = type;
3858                 } else {
3859                         type->next = first;
3860                         first      = type;
3861                 }
3862                 if (last == p) {
3863                         last = type;
3864                 }
3865         }
3866
3867 declarator_finished:
3868         /* append inner_types at the end of the list, we don't to set last anymore
3869          * as it's not needed anymore */
3870         if (last == NULL) {
3871                 assert(first == NULL);
3872                 first = inner_types;
3873         } else {
3874                 last->next = inner_types;
3875         }
3876
3877         return first;
3878 end_error:
3879         return NULL;
3880 }
3881
3882 static void parse_declaration_attributes(declaration_t *declaration)
3883 {
3884         gnu_attribute_t  *attributes = NULL;
3885         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
3886
3887         if (declaration == NULL)
3888                 return;
3889
3890         declaration->modifiers |= modifiers;
3891         /* check if we have these stupid mode attributes... */
3892         type_t *old_type = declaration->type;
3893         if (old_type == NULL)
3894                 return;
3895
3896         gnu_attribute_t *attribute = attributes;
3897         for ( ; attribute != NULL; attribute = attribute->next) {
3898                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
3899                         continue;
3900
3901                 atomic_type_kind_t  akind = attribute->u.akind;
3902                 if (!is_type_signed(old_type)) {
3903                         switch(akind) {
3904                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
3905                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
3906                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
3907                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
3908                         default:
3909                                 panic("invalid akind in mode attribute");
3910                         }
3911                 }
3912                 declaration->type
3913                         = make_atomic_type(akind, old_type->base.qualifiers);
3914         }
3915 }
3916
3917 static type_t *construct_declarator_type(construct_type_t *construct_list,
3918                                          type_t *type)
3919 {
3920         construct_type_t *iter = construct_list;
3921         for( ; iter != NULL; iter = iter->next) {
3922                 switch(iter->kind) {
3923                 case CONSTRUCT_INVALID:
3924                         internal_errorf(HERE, "invalid type construction found");
3925                 case CONSTRUCT_FUNCTION: {
3926                         construct_function_type_t *construct_function_type
3927                                 = (construct_function_type_t*) iter;
3928
3929                         type_t *function_type = construct_function_type->function_type;
3930
3931                         function_type->function.return_type = type;
3932
3933                         type_t *skipped_return_type = skip_typeref(type);
3934                         if (is_type_function(skipped_return_type)) {
3935                                 errorf(HERE, "function returning function is not allowed");
3936                                 type = type_error_type;
3937                         } else if (is_type_array(skipped_return_type)) {
3938                                 errorf(HERE, "function returning array is not allowed");
3939                                 type = type_error_type;
3940                         } else {
3941                                 type = function_type;
3942                         }
3943                         break;
3944                 }
3945
3946                 case CONSTRUCT_POINTER: {
3947                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
3948                         type_t           *pointer_type   = allocate_type_zero(TYPE_POINTER, &null_position);
3949                         pointer_type->pointer.points_to  = type;
3950                         pointer_type->base.qualifiers    = parsed_pointer->type_qualifiers;
3951
3952                         type = pointer_type;
3953                         break;
3954                 }
3955
3956                 case CONSTRUCT_ARRAY: {
3957                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
3958                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY, &null_position);
3959
3960                         expression_t *size_expression = parsed_array->size;
3961                         if (size_expression != NULL) {
3962                                 size_expression
3963                                         = create_implicit_cast(size_expression, type_size_t);
3964                         }
3965
3966                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
3967                         array_type->array.element_type    = type;
3968                         array_type->array.is_static       = parsed_array->is_static;
3969                         array_type->array.is_variable     = parsed_array->is_variable;
3970                         array_type->array.size_expression = size_expression;
3971
3972                         if (size_expression != NULL) {
3973                                 if (is_constant_expression(size_expression)) {
3974                                         array_type->array.size_constant = true;
3975                                         array_type->array.size
3976                                                 = fold_constant(size_expression);
3977                                 } else {
3978                                         array_type->array.is_vla = true;
3979                                 }
3980                         }
3981
3982                         type_t *skipped_type = skip_typeref(type);
3983                         if (is_type_atomic(skipped_type, ATOMIC_TYPE_VOID)) {
3984                                 errorf(HERE, "array of void is not allowed");
3985                                 type = type_error_type;
3986                         } else {
3987                                 type = array_type;
3988                         }
3989                         break;
3990                 }
3991                 }
3992
3993                 type_t *hashed_type = typehash_insert(type);
3994                 if (hashed_type != type) {
3995                         /* the function type was constructed earlier freeing it here will
3996                          * destroy other types... */
3997                         if (iter->kind != CONSTRUCT_FUNCTION) {
3998                                 free_type(type);
3999                         }
4000                         type = hashed_type;
4001                 }
4002         }
4003
4004         return type;
4005 }
4006
4007 static declaration_t *parse_declarator(
4008                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
4009 {
4010         declaration_t *const declaration    = allocate_declaration_zero();
4011         declaration->source_position        = specifiers->source_position;
4012         declaration->declared_storage_class = specifiers->declared_storage_class;
4013         declaration->modifiers              = specifiers->modifiers;
4014         declaration->deprecated_string      = specifiers->deprecated_string;
4015         declaration->get_property_sym       = specifiers->get_property_sym;
4016         declaration->put_property_sym       = specifiers->put_property_sym;
4017         declaration->is_inline              = specifiers->is_inline;
4018
4019         declaration->storage_class          = specifiers->declared_storage_class;
4020         if (declaration->storage_class == STORAGE_CLASS_NONE
4021                         && scope != global_scope) {
4022                 declaration->storage_class = STORAGE_CLASS_AUTO;
4023         }
4024
4025         if (specifiers->alignment != 0) {
4026                 /* TODO: add checks here */
4027                 declaration->alignment = specifiers->alignment;
4028         }
4029
4030         construct_type_t *construct_type
4031                 = parse_inner_declarator(declaration, may_be_abstract);
4032         type_t *const type = specifiers->type;
4033         declaration->type = construct_declarator_type(construct_type, type);
4034
4035         parse_declaration_attributes(declaration);
4036
4037         fix_declaration_type(declaration);
4038
4039         if (construct_type != NULL) {
4040                 obstack_free(&temp_obst, construct_type);
4041         }
4042
4043         return declaration;
4044 }
4045
4046 static type_t *parse_abstract_declarator(type_t *base_type)
4047 {
4048         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4049
4050         type_t *result = construct_declarator_type(construct_type, base_type);
4051         if (construct_type != NULL) {
4052                 obstack_free(&temp_obst, construct_type);
4053         }
4054
4055         return result;
4056 }
4057
4058 static declaration_t *append_declaration(declaration_t* const declaration)
4059 {
4060         if (last_declaration != NULL) {
4061                 last_declaration->next = declaration;
4062         } else {
4063                 scope->declarations = declaration;
4064         }
4065         last_declaration = declaration;
4066         return declaration;
4067 }
4068
4069 /**
4070  * Check if the declaration of main is suspicious.  main should be a
4071  * function with external linkage, returning int, taking either zero
4072  * arguments, two, or three arguments of appropriate types, ie.
4073  *
4074  * int main([ int argc, char **argv [, char **env ] ]).
4075  *
4076  * @param decl    the declaration to check
4077  * @param type    the function type of the declaration
4078  */
4079 static void check_type_of_main(const declaration_t *const decl, const function_type_t *const func_type)
4080 {
4081         if (decl->storage_class == STORAGE_CLASS_STATIC) {
4082                 warningf(&decl->source_position,
4083                          "'main' is normally a non-static function");
4084         }
4085         if (skip_typeref(func_type->return_type) != type_int) {
4086                 warningf(&decl->source_position,
4087                          "return type of 'main' should be 'int', but is '%T'",
4088                          func_type->return_type);
4089         }
4090         const function_parameter_t *parm = func_type->parameters;
4091         if (parm != NULL) {
4092                 type_t *const first_type = parm->type;
4093                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4094                         warningf(&decl->source_position,
4095                                  "first argument of 'main' should be 'int', but is '%T'", first_type);
4096                 }
4097                 parm = parm->next;
4098                 if (parm != NULL) {
4099                         type_t *const second_type = parm->type;
4100                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4101                                 warningf(&decl->source_position,
4102                                          "second argument of 'main' should be 'char**', but is '%T'", second_type);
4103                         }
4104                         parm = parm->next;
4105                         if (parm != NULL) {
4106                                 type_t *const third_type = parm->type;
4107                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4108                                         warningf(&decl->source_position,
4109                                                  "third argument of 'main' should be 'char**', but is '%T'", third_type);
4110                                 }
4111                                 parm = parm->next;
4112                                 if (parm != NULL)
4113                                         goto warn_arg_count;
4114                         }
4115                 } else {
4116 warn_arg_count:
4117                         warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
4118                 }
4119         }
4120 }
4121
4122 /**
4123  * Check if a symbol is the equal to "main".
4124  */
4125 static bool is_sym_main(const symbol_t *const sym)
4126 {
4127         return strcmp(sym->string, "main") == 0;
4128 }
4129
4130 static declaration_t *internal_record_declaration(
4131         declaration_t *const declaration,
4132         const bool is_definition)
4133 {
4134         const symbol_t *const symbol  = declaration->symbol;
4135         const namespace_t     namespc = (namespace_t)declaration->namespc;
4136
4137         assert(symbol != NULL);
4138         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4139
4140         type_t *const orig_type = declaration->type;
4141         type_t *const type      = skip_typeref(orig_type);
4142         if (is_type_function(type) &&
4143                         type->function.unspecified_parameters &&
4144                         warning.strict_prototypes &&
4145                         previous_declaration == NULL) {
4146                 warningf(&declaration->source_position,
4147                          "function declaration '%#T' is not a prototype",
4148                          orig_type, declaration->symbol);
4149         }
4150
4151         if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
4152                 check_type_of_main(declaration, &type->function);
4153         }
4154
4155         if (warning.nested_externs                             &&
4156             declaration->storage_class == STORAGE_CLASS_EXTERN &&
4157             scope                      != global_scope) {
4158                 warningf(&declaration->source_position,
4159                          "nested extern declaration of '%#T'", declaration->type, symbol);
4160         }
4161
4162         assert(declaration != previous_declaration);
4163         if (previous_declaration != NULL
4164                         && previous_declaration->parent_scope == scope) {
4165                 /* can happen for K&R style declarations */
4166                 if (previous_declaration->type == NULL) {
4167                         previous_declaration->type = declaration->type;
4168                 }
4169
4170                 const type_t *prev_type = skip_typeref(previous_declaration->type);
4171                 if (!types_compatible(type, prev_type)) {
4172                         errorf(&declaration->source_position,
4173                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
4174                                    orig_type, symbol, previous_declaration->type, symbol,
4175                                    &previous_declaration->source_position);
4176                 } else {
4177                         unsigned old_storage_class = previous_declaration->storage_class;
4178                         if (old_storage_class == STORAGE_CLASS_ENUM_ENTRY) {
4179                                 errorf(&declaration->source_position,
4180                                            "redeclaration of enum entry '%Y' (declared %P)",
4181                                            symbol, &previous_declaration->source_position);
4182                                 return previous_declaration;
4183                         }
4184
4185                         if (warning.redundant_decls                                     &&
4186                             is_definition                                               &&
4187                             previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
4188                             !(previous_declaration->modifiers & DM_USED)                &&
4189                             !previous_declaration->used) {
4190                                 warningf(&previous_declaration->source_position,
4191                                          "unnecessary static forward declaration for '%#T'",
4192                                          previous_declaration->type, symbol);
4193                         }
4194
4195                         unsigned new_storage_class = declaration->storage_class;
4196
4197                         if (is_type_incomplete(prev_type)) {
4198                                 previous_declaration->type = type;
4199                                 prev_type                  = type;
4200                         }
4201
4202                         /* pretend no storage class means extern for function
4203                          * declarations (except if the previous declaration is neither
4204                          * none nor extern) */
4205                         if (is_type_function(type)) {
4206                                 if (prev_type->function.unspecified_parameters) {
4207                                         previous_declaration->type = type;
4208                                         prev_type                  = type;
4209                                 }
4210
4211                                 switch (old_storage_class) {
4212                                 case STORAGE_CLASS_NONE:
4213                                         old_storage_class = STORAGE_CLASS_EXTERN;
4214                                         /* FALLTHROUGH */
4215
4216                                 case STORAGE_CLASS_EXTERN:
4217                                         if (is_definition) {
4218                                                 if (warning.missing_prototypes &&
4219                                                     prev_type->function.unspecified_parameters &&
4220                                                     !is_sym_main(symbol)) {
4221                                                         warningf(&declaration->source_position,
4222                                                                          "no previous prototype for '%#T'",
4223                                                                          orig_type, symbol);
4224                                                 }
4225                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4226                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4227                                         }
4228                                         break;
4229
4230                                 default:
4231                                         break;
4232                                 }
4233                         }
4234
4235                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
4236                                         new_storage_class == STORAGE_CLASS_EXTERN) {
4237 warn_redundant_declaration:
4238                                 if (!is_definition          &&
4239                                     warning.redundant_decls &&
4240                                     strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
4241                                         warningf(&declaration->source_position,
4242                                                  "redundant declaration for '%Y' (declared %P)",
4243                                                  symbol, &previous_declaration->source_position);
4244                                 }
4245                         } else if (current_function == NULL) {
4246                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
4247                                     new_storage_class == STORAGE_CLASS_STATIC) {
4248                                         errorf(&declaration->source_position,
4249                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
4250                                                symbol, &previous_declaration->source_position);
4251                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4252                                         previous_declaration->storage_class          = STORAGE_CLASS_NONE;
4253                                         previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
4254                                 } else {
4255                                         goto warn_redundant_declaration;
4256                                 }
4257                         } else if (old_storage_class == new_storage_class) {
4258                                 errorf(&declaration->source_position,
4259                                        "redeclaration of '%Y' (declared %P)",
4260                                        symbol, &previous_declaration->source_position);
4261                         } else {
4262                                 errorf(&declaration->source_position,
4263                                        "redeclaration of '%Y' with different linkage (declared %P)",
4264                                        symbol, &previous_declaration->source_position);
4265                         }
4266                 }
4267
4268                 previous_declaration->modifiers |= declaration->modifiers;
4269                 previous_declaration->is_inline |= declaration->is_inline;
4270                 return previous_declaration;
4271         } else if (is_type_function(type)) {
4272                 if (is_definition &&
4273                     declaration->storage_class != STORAGE_CLASS_STATIC) {
4274                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4275                                 warningf(&declaration->source_position,
4276                                          "no previous prototype for '%#T'", orig_type, symbol);
4277                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4278                                 warningf(&declaration->source_position,
4279                                          "no previous declaration for '%#T'", orig_type,
4280                                          symbol);
4281                         }
4282                 }
4283         } else {
4284                 if (warning.missing_declarations &&
4285                     scope == global_scope && (
4286                       declaration->storage_class == STORAGE_CLASS_NONE ||
4287                       declaration->storage_class == STORAGE_CLASS_THREAD
4288                     )) {
4289                         warningf(&declaration->source_position,
4290                                  "no previous declaration for '%#T'", orig_type, symbol);
4291                 }
4292         }
4293
4294         assert(declaration->parent_scope == NULL);
4295         assert(scope != NULL);
4296
4297         declaration->parent_scope = scope;
4298
4299         environment_push(declaration);
4300         return append_declaration(declaration);
4301 }
4302
4303 static declaration_t *record_declaration(declaration_t *declaration)
4304 {
4305         return internal_record_declaration(declaration, false);
4306 }
4307
4308 static declaration_t *record_definition(declaration_t *declaration)
4309 {
4310         return internal_record_declaration(declaration, true);
4311 }
4312
4313 static void parser_error_multiple_definition(declaration_t *declaration,
4314                 const source_position_t *source_position)
4315 {
4316         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
4317                declaration->symbol, &declaration->source_position);
4318 }
4319
4320 static bool is_declaration_specifier(const token_t *token,
4321                                      bool only_specifiers_qualifiers)
4322 {
4323         switch(token->type) {
4324                 TYPE_SPECIFIERS
4325                 TYPE_QUALIFIERS
4326                         return true;
4327                 case T_IDENTIFIER:
4328                         return is_typedef_symbol(token->v.symbol);
4329
4330                 case T___extension__:
4331                 STORAGE_CLASSES
4332                         return !only_specifiers_qualifiers;
4333
4334                 default:
4335                         return false;
4336         }
4337 }
4338
4339 static void parse_init_declarator_rest(declaration_t *declaration)
4340 {
4341         eat('=');
4342
4343         type_t *orig_type = declaration->type;
4344         type_t *type      = skip_typeref(orig_type);
4345
4346         if (declaration->init.initializer != NULL) {
4347                 parser_error_multiple_definition(declaration, HERE);
4348         }
4349
4350         bool must_be_constant = false;
4351         if (declaration->storage_class == STORAGE_CLASS_STATIC
4352                         || declaration->storage_class == STORAGE_CLASS_THREAD_STATIC
4353                         || declaration->parent_scope == global_scope) {
4354                 must_be_constant = true;
4355         }
4356
4357         parse_initializer_env_t env;
4358         env.type             = orig_type;
4359         env.must_be_constant = must_be_constant;
4360         env.declaration      = declaration;
4361
4362         initializer_t *initializer = parse_initializer(&env);
4363
4364         if (env.type != orig_type) {
4365                 orig_type         = env.type;
4366                 type              = skip_typeref(orig_type);
4367                 declaration->type = env.type;
4368         }
4369
4370         if (is_type_function(type)) {
4371                 errorf(&declaration->source_position,
4372                        "initializers not allowed for function types at declator '%Y' (type '%T')",
4373                        declaration->symbol, orig_type);
4374         } else {
4375                 declaration->init.initializer = initializer;
4376         }
4377 }
4378
4379 /* parse rest of a declaration without any declarator */
4380 static void parse_anonymous_declaration_rest(
4381                 const declaration_specifiers_t *specifiers,
4382                 parsed_declaration_func finished_declaration)
4383 {
4384         eat(';');
4385
4386         declaration_t *const declaration    = allocate_declaration_zero();
4387         declaration->type                   = specifiers->type;
4388         declaration->declared_storage_class = specifiers->declared_storage_class;
4389         declaration->source_position        = specifiers->source_position;
4390         declaration->modifiers              = specifiers->modifiers;
4391
4392         if (declaration->declared_storage_class != STORAGE_CLASS_NONE) {
4393                 warningf(&declaration->source_position,
4394                          "useless storage class in empty declaration");
4395         }
4396         declaration->storage_class = STORAGE_CLASS_NONE;
4397
4398         type_t *type = declaration->type;
4399         switch (type->kind) {
4400                 case TYPE_COMPOUND_STRUCT:
4401                 case TYPE_COMPOUND_UNION: {
4402                         if (type->compound.declaration->symbol == NULL) {
4403                                 warningf(&declaration->source_position,
4404                                          "unnamed struct/union that defines no instances");
4405                         }
4406                         break;
4407                 }
4408
4409                 case TYPE_ENUM:
4410                         break;
4411
4412                 default:
4413                         warningf(&declaration->source_position, "empty declaration");
4414                         break;
4415         }
4416
4417         finished_declaration(declaration);
4418 }
4419
4420 static void parse_declaration_rest(declaration_t *ndeclaration,
4421                 const declaration_specifiers_t *specifiers,
4422                 parsed_declaration_func finished_declaration)
4423 {
4424         add_anchor_token(';');
4425         add_anchor_token('=');
4426         add_anchor_token(',');
4427         while(true) {
4428                 declaration_t *declaration = finished_declaration(ndeclaration);
4429
4430                 type_t *orig_type = declaration->type;
4431                 type_t *type      = skip_typeref(orig_type);
4432
4433                 if (type->kind != TYPE_FUNCTION &&
4434                     declaration->is_inline &&
4435                     is_type_valid(type)) {
4436                         warningf(&declaration->source_position,
4437                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
4438                 }
4439
4440                 if (token.type == '=') {
4441                         parse_init_declarator_rest(declaration);
4442                 }
4443
4444                 if (token.type != ',')
4445                         break;
4446                 eat(',');
4447
4448                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
4449         }
4450         expect(';');
4451
4452 end_error:
4453         rem_anchor_token(';');
4454         rem_anchor_token('=');
4455         rem_anchor_token(',');
4456 }
4457
4458 static declaration_t *finished_kr_declaration(declaration_t *declaration)
4459 {
4460         symbol_t *symbol  = declaration->symbol;
4461         if (symbol == NULL) {
4462                 errorf(HERE, "anonymous declaration not valid as function parameter");
4463                 return declaration;
4464         }
4465         namespace_t namespc = (namespace_t) declaration->namespc;
4466         if (namespc != NAMESPACE_NORMAL) {
4467                 return record_declaration(declaration);
4468         }
4469
4470         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4471         if (previous_declaration == NULL ||
4472                         previous_declaration->parent_scope != scope) {
4473                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4474                        symbol);
4475                 return declaration;
4476         }
4477
4478         if (previous_declaration->type == NULL) {
4479                 previous_declaration->type          = declaration->type;
4480                 previous_declaration->declared_storage_class = declaration->declared_storage_class;
4481                 previous_declaration->storage_class = declaration->storage_class;
4482                 previous_declaration->parent_scope  = scope;
4483                 return previous_declaration;
4484         } else {
4485                 return record_declaration(declaration);
4486         }
4487 }
4488
4489 static void parse_declaration(parsed_declaration_func finished_declaration)
4490 {
4491         declaration_specifiers_t specifiers;
4492         memset(&specifiers, 0, sizeof(specifiers));
4493         parse_declaration_specifiers(&specifiers);
4494
4495         if (token.type == ';') {
4496                 parse_anonymous_declaration_rest(&specifiers, append_declaration);
4497         } else {
4498                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
4499                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
4500         }
4501 }
4502
4503 static type_t *get_default_promoted_type(type_t *orig_type)
4504 {
4505         type_t *result = orig_type;
4506
4507         type_t *type = skip_typeref(orig_type);
4508         if (is_type_integer(type)) {
4509                 result = promote_integer(type);
4510         } else if (type == type_float) {
4511                 result = type_double;
4512         }
4513
4514         return result;
4515 }
4516
4517 static void parse_kr_declaration_list(declaration_t *declaration)
4518 {
4519         type_t *type = skip_typeref(declaration->type);
4520         if (!is_type_function(type))
4521                 return;
4522
4523         if (!type->function.kr_style_parameters)
4524                 return;
4525
4526         /* push function parameters */
4527         int       top        = environment_top();
4528         scope_t  *last_scope = scope;
4529         set_scope(&declaration->scope);
4530
4531         declaration_t *parameter = declaration->scope.declarations;
4532         for ( ; parameter != NULL; parameter = parameter->next) {
4533                 assert(parameter->parent_scope == NULL);
4534                 parameter->parent_scope = scope;
4535                 environment_push(parameter);
4536         }
4537
4538         /* parse declaration list */
4539         while (is_declaration_specifier(&token, false)) {
4540                 parse_declaration(finished_kr_declaration);
4541         }
4542
4543         /* pop function parameters */
4544         assert(scope == &declaration->scope);
4545         set_scope(last_scope);
4546         environment_pop_to(top);
4547
4548         /* update function type */
4549         type_t *new_type = duplicate_type(type);
4550
4551         function_parameter_t *parameters     = NULL;
4552         function_parameter_t *last_parameter = NULL;
4553
4554         declaration_t *parameter_declaration = declaration->scope.declarations;
4555         for( ; parameter_declaration != NULL;
4556                         parameter_declaration = parameter_declaration->next) {
4557                 type_t *parameter_type = parameter_declaration->type;
4558                 if (parameter_type == NULL) {
4559                         if (strict_mode) {
4560                                 errorf(HERE, "no type specified for function parameter '%Y'",
4561                                        parameter_declaration->symbol);
4562                         } else {
4563                                 if (warning.implicit_int) {
4564                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
4565                                                 parameter_declaration->symbol);
4566                                 }
4567                                 parameter_type              = type_int;
4568                                 parameter_declaration->type = parameter_type;
4569                         }
4570                 }
4571
4572                 semantic_parameter(parameter_declaration);
4573                 parameter_type = parameter_declaration->type;
4574
4575                 /*
4576                  * we need the default promoted types for the function type
4577                  */
4578                 parameter_type = get_default_promoted_type(parameter_type);
4579
4580                 function_parameter_t *function_parameter
4581                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
4582                 memset(function_parameter, 0, sizeof(function_parameter[0]));
4583
4584                 function_parameter->type = parameter_type;
4585                 if (last_parameter != NULL) {
4586                         last_parameter->next = function_parameter;
4587                 } else {
4588                         parameters = function_parameter;
4589                 }
4590                 last_parameter = function_parameter;
4591         }
4592
4593         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
4594          * prototype */
4595         new_type->function.parameters             = parameters;
4596         new_type->function.unspecified_parameters = true;
4597
4598         type = typehash_insert(new_type);
4599         if (type != new_type) {
4600                 obstack_free(type_obst, new_type);
4601         }
4602
4603         declaration->type = type;
4604 }
4605
4606 static bool first_err = true;
4607
4608 /**
4609  * When called with first_err set, prints the name of the current function,
4610  * else does noting.
4611  */
4612 static void print_in_function(void)
4613 {
4614         if (first_err) {
4615                 first_err = false;
4616                 diagnosticf("%s: In function '%Y':\n",
4617                         current_function->source_position.input_name,
4618                         current_function->symbol);
4619         }
4620 }
4621
4622 /**
4623  * Check if all labels are defined in the current function.
4624  * Check if all labels are used in the current function.
4625  */
4626 static void check_labels(void)
4627 {
4628         for (const goto_statement_t *goto_statement = goto_first;
4629             goto_statement != NULL;
4630             goto_statement = goto_statement->next) {
4631                 declaration_t *label = goto_statement->label;
4632
4633                 label->used = true;
4634                 if (label->source_position.input_name == NULL) {
4635                         print_in_function();
4636                         errorf(&goto_statement->base.source_position,
4637                                "label '%Y' used but not defined", label->symbol);
4638                  }
4639         }
4640         goto_first = goto_last = NULL;
4641
4642         if (warning.unused_label) {
4643                 for (const label_statement_t *label_statement = label_first;
4644                          label_statement != NULL;
4645                          label_statement = label_statement->next) {
4646                         const declaration_t *label = label_statement->label;
4647
4648                         if (! label->used) {
4649                                 print_in_function();
4650                                 warningf(&label_statement->base.source_position,
4651                                         "label '%Y' defined but not used", label->symbol);
4652                         }
4653                 }
4654         }
4655         label_first = label_last = NULL;
4656 }
4657
4658 /**
4659  * Check declarations of current_function for unused entities.
4660  */
4661 static void check_declarations(void)
4662 {
4663         if (warning.unused_parameter) {
4664                 const scope_t *scope = &current_function->scope;
4665
4666                 const declaration_t *parameter = scope->declarations;
4667                 for (; parameter != NULL; parameter = parameter->next) {
4668                         if (! parameter->used) {
4669                                 print_in_function();
4670                                 warningf(&parameter->source_position,
4671                                          "unused parameter '%Y'", parameter->symbol);
4672                         }
4673                 }
4674         }
4675         if (warning.unused_variable) {
4676         }
4677 }
4678
4679 static int determine_truth(expression_t const* const cond)
4680 {
4681         return
4682                 !is_constant_expression(cond) ? 0 :
4683                 fold_constant(cond) != 0      ? 1 :
4684                 -1;
4685 }
4686
4687 static bool noreturn_candidate;
4688
4689 static void check_reachable(statement_t *const stmt)
4690 {
4691         if (stmt->base.reachable)
4692                 return;
4693         if (stmt->kind != STATEMENT_DO_WHILE)
4694                 stmt->base.reachable = true;
4695
4696         statement_t *last = stmt;
4697         statement_t *next;
4698         switch (stmt->kind) {
4699                 case STATEMENT_INVALID:
4700                 case STATEMENT_EMPTY:
4701                 case STATEMENT_DECLARATION:
4702                 case STATEMENT_ASM:
4703                         next = stmt->base.next;
4704                         break;
4705
4706                 case STATEMENT_COMPOUND:
4707                         next = stmt->compound.statements;
4708                         break;
4709
4710                 case STATEMENT_RETURN:
4711                         noreturn_candidate = false;
4712                         return;
4713
4714                 case STATEMENT_IF: {
4715                         if_statement_t const* const ifs = &stmt->ifs;
4716                         int            const        val = determine_truth(ifs->condition);
4717
4718                         if (val >= 0)
4719                                 check_reachable(ifs->true_statement);
4720
4721                         if (val > 0)
4722                                 return;
4723
4724                         if (ifs->false_statement != NULL) {
4725                                 check_reachable(ifs->false_statement);
4726                                 return;
4727                         }
4728
4729                         next = stmt->base.next;
4730                         break;
4731                 }
4732
4733                 case STATEMENT_SWITCH: {
4734                         switch_statement_t const *const switchs = &stmt->switchs;
4735                         expression_t       const *const expr    = switchs->expression;
4736
4737                         if (is_constant_expression(expr)) {
4738                                 long                    const val      = fold_constant(expr);
4739                                 case_label_statement_t *      defaults = NULL;
4740                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4741                                         if (i->expression == NULL) {
4742                                                 defaults = i;
4743                                                 continue;
4744                                         }
4745
4746                                         expression_t *const case_expr = i->expression;
4747                                         if (is_constant_expression(case_expr) &&
4748                                             fold_constant(case_expr) == val) {
4749                                                 check_reachable((statement_t*)i);
4750                                                 return;
4751                                         }
4752                                 }
4753
4754                                 if (defaults != NULL) {
4755                                         check_reachable((statement_t*)defaults);
4756                                         return;
4757                                 }
4758                         } else {
4759                                 bool has_default = false;
4760                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4761                                         if (i->expression == NULL)
4762                                                 has_default = true;
4763
4764                                         check_reachable((statement_t*)i);
4765                                 }
4766
4767                                 if (has_default)
4768                                         return;
4769                         }
4770
4771                         next = stmt->base.next;
4772                         break;
4773                 }
4774
4775                 case STATEMENT_EXPRESSION: {
4776                         /* Check for noreturn function call */
4777                         expression_t const *const expr = stmt->expression.expression;
4778                         if (expr->kind == EXPR_CALL) {
4779                                 expression_t const *const func = expr->call.function;
4780                                 if (func->kind == EXPR_REFERENCE) {
4781                                         declaration_t const *const decl = func->reference.declaration;
4782                                         if (decl != NULL && decl->modifiers & DM_NORETURN) {
4783                                                 return;
4784                                         }
4785                                 }
4786                         }
4787
4788                         next = stmt->base.next;
4789                         break;
4790                 }
4791
4792                 case STATEMENT_CONTINUE: {
4793                         statement_t *parent = stmt;
4794                         for (;;) {
4795                                 parent = parent->base.parent;
4796                                 if (parent == NULL) /* continue not within loop */
4797                                         return;
4798
4799                                 next = parent;
4800                                 switch (parent->kind) {
4801                                         case STATEMENT_WHILE:    goto continue_while;
4802                                         case STATEMENT_DO_WHILE: goto continue_do_while;
4803                                         case STATEMENT_FOR:      goto continue_for;
4804
4805                                         default: break;
4806                                 }
4807                         }
4808                 }
4809
4810                 case STATEMENT_BREAK: {
4811                         statement_t *parent = stmt;
4812                         for (;;) {
4813                                 parent = parent->base.parent;
4814                                 if (parent == NULL) /* break not within loop/switch */
4815                                         return;
4816
4817                                 switch (parent->kind) {
4818                                         case STATEMENT_SWITCH:
4819                                         case STATEMENT_WHILE:
4820                                         case STATEMENT_DO_WHILE:
4821                                         case STATEMENT_FOR:
4822                                                 last = parent;
4823                                                 next = parent->base.next;
4824                                                 goto found_break_parent;
4825
4826                                         default: break;
4827                                 }
4828                         }
4829 found_break_parent:
4830                         break;
4831                 }
4832
4833                 case STATEMENT_GOTO:
4834                         next = stmt->gotos.label->init.statement;
4835                         if (next == NULL) /* missing label */
4836                                 return;
4837                         break;
4838
4839                 case STATEMENT_LABEL:
4840                         next = stmt->label.statement;
4841                         break;
4842
4843                 case STATEMENT_CASE_LABEL:
4844                         next = stmt->case_label.statement;
4845                         break;
4846
4847                 case STATEMENT_WHILE: {
4848                         while_statement_t const *const whiles = &stmt->whiles;
4849                         int                      const val    = determine_truth(whiles->condition);
4850
4851                         if (val >= 0)
4852                                 check_reachable(whiles->body);
4853
4854                         if (val > 0)
4855                                 return;
4856
4857                         next = stmt->base.next;
4858                         break;
4859                 }
4860
4861                 case STATEMENT_DO_WHILE:
4862                         next = stmt->do_while.body;
4863                         break;
4864
4865                 case STATEMENT_FOR: {
4866                         for_statement_t *const fors = &stmt->fors;
4867
4868                         if (fors->condition_reachable)
4869                                 return;
4870                         fors->condition_reachable = true;
4871
4872                         expression_t const *const cond = fors->condition;
4873                         int          const        val  =
4874                                 cond == NULL ? 1 : determine_truth(cond);
4875
4876                         if (val >= 0)
4877                                 check_reachable(fors->body);
4878
4879                         if (val > 0)
4880                                 return;
4881
4882                         next = stmt->base.next;
4883                         break;
4884                 }
4885
4886                 case STATEMENT_MS_TRY:
4887                 case STATEMENT_LEAVE:
4888                         panic("unimplemented");
4889         }
4890
4891         while (next == NULL) {
4892                 next = last->base.parent;
4893                 if (next == NULL) {
4894                         noreturn_candidate = false;
4895
4896                         type_t *const type = current_function->type;
4897                         assert(is_type_function(type));
4898                         type_t *const ret  = skip_typeref(type->function.return_type);
4899                         if (warning.return_type                    &&
4900                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
4901                             is_type_valid(ret)                     &&
4902                             !is_sym_main(current_function->symbol)) {
4903                                 warningf(&stmt->base.source_position,
4904                                          "control reaches end of non-void function");
4905                         }
4906                         return;
4907                 }
4908
4909                 switch (next->kind) {
4910                         case STATEMENT_INVALID:
4911                         case STATEMENT_EMPTY:
4912                         case STATEMENT_DECLARATION:
4913                         case STATEMENT_EXPRESSION:
4914                         case STATEMENT_ASM:
4915                         case STATEMENT_RETURN:
4916                         case STATEMENT_CONTINUE:
4917                         case STATEMENT_BREAK:
4918                         case STATEMENT_GOTO:
4919                         case STATEMENT_LEAVE:
4920                                 panic("invalid control flow in function");
4921
4922                         case STATEMENT_COMPOUND:
4923                         case STATEMENT_IF:
4924                         case STATEMENT_SWITCH:
4925                         case STATEMENT_LABEL:
4926                         case STATEMENT_CASE_LABEL:
4927                                 last = next;
4928                                 next = next->base.next;
4929                                 break;
4930
4931                         case STATEMENT_WHILE: {
4932 continue_while:
4933                                 if (next->base.reachable)
4934                                         return;
4935                                 next->base.reachable = true;
4936
4937                                 while_statement_t const *const whiles = &next->whiles;
4938                                 int                      const val    = determine_truth(whiles->condition);
4939
4940                                 if (val >= 0)
4941                                         check_reachable(whiles->body);
4942
4943                                 if (val > 0)
4944                                         return;
4945
4946                                 last = next;
4947                                 next = next->base.next;
4948                                 break;
4949                         }
4950
4951                         case STATEMENT_DO_WHILE: {
4952 continue_do_while:
4953                                 if (next->base.reachable)
4954                                         return;
4955                                 next->base.reachable = true;
4956
4957                                 do_while_statement_t const *const dw  = &next->do_while;
4958                                 int                  const        val = determine_truth(dw->condition);
4959
4960                                 if (val >= 0)
4961                                         check_reachable(dw->body);
4962
4963                                 if (val > 0)
4964                                         return;
4965
4966                                 last = next;
4967                                 next = next->base.next;
4968                                 break;
4969                         }
4970
4971                         case STATEMENT_FOR: {
4972 continue_for:;
4973                                 for_statement_t *const fors = &next->fors;
4974
4975                                 fors->step_reachable = true;
4976
4977                                 if (fors->condition_reachable)
4978                                         return;
4979                                 fors->condition_reachable = true;
4980
4981                                 expression_t const *const cond = fors->condition;
4982                                 int          const        val  =
4983                                         cond == NULL ? 1 : determine_truth(cond);
4984
4985                                 if (val >= 0)
4986                                         check_reachable(fors->body);
4987
4988                                 if (val > 0)
4989                                         return;
4990
4991                                 last = next;
4992                                 next = next->base.next;
4993                                 break;
4994                         }
4995
4996                         case STATEMENT_MS_TRY:
4997                                 panic("unimplemented");
4998                 }
4999         }
5000
5001         if (next == NULL) {
5002                 next = stmt->base.parent;
5003                 if (next == NULL) {
5004                         warningf(&stmt->base.source_position,
5005                                  "control reaches end of non-void function");
5006                 }
5007         }
5008
5009         check_reachable(next);
5010 }
5011
5012 static void check_unreachable(statement_t const* const stmt)
5013 {
5014         if (!stmt->base.reachable            &&
5015             stmt->kind != STATEMENT_COMPOUND &&
5016             stmt->kind != STATEMENT_DO_WHILE &&
5017             stmt->kind != STATEMENT_FOR) {
5018                 warningf(&stmt->base.source_position, "statement is unreachable");
5019         }
5020
5021         switch (stmt->kind) {
5022                 case STATEMENT_INVALID:
5023                 case STATEMENT_EMPTY:
5024                 case STATEMENT_RETURN:
5025                 case STATEMENT_DECLARATION:
5026                 case STATEMENT_EXPRESSION:
5027                 case STATEMENT_CONTINUE:
5028                 case STATEMENT_BREAK:
5029                 case STATEMENT_GOTO:
5030                 case STATEMENT_ASM:
5031                 case STATEMENT_LEAVE:
5032                         break;
5033
5034                 case STATEMENT_COMPOUND:
5035                         if (stmt->compound.statements)
5036                                 check_unreachable(stmt->compound.statements);
5037                         break;
5038
5039                 case STATEMENT_IF:
5040                         check_unreachable(stmt->ifs.true_statement);
5041                         if (stmt->ifs.false_statement != NULL)
5042                                 check_unreachable(stmt->ifs.false_statement);
5043                         break;
5044
5045                 case STATEMENT_SWITCH:
5046                         check_unreachable(stmt->switchs.body);
5047                         break;
5048
5049                 case STATEMENT_LABEL:
5050                         check_unreachable(stmt->label.statement);
5051                         break;
5052
5053                 case STATEMENT_CASE_LABEL:
5054                         check_unreachable(stmt->case_label.statement);
5055                         break;
5056
5057                 case STATEMENT_WHILE:
5058                         check_unreachable(stmt->whiles.body);
5059                         break;
5060
5061                 case STATEMENT_DO_WHILE:
5062                         check_unreachable(stmt->do_while.body);
5063                         if (!stmt->base.reachable) {
5064                                 expression_t const *const cond = stmt->do_while.condition;
5065                                 if (determine_truth(cond) >= 0) {
5066                                         warningf(&cond->base.source_position,
5067                                                  "condition of do-while-loop is unreachable");
5068                                 }
5069                         }
5070                         break;
5071
5072                 case STATEMENT_FOR: {
5073                         for_statement_t const* const fors = &stmt->fors;
5074
5075                         // if init and step are unreachable, cond is unreachable, too
5076                         if (!stmt->base.reachable && !fors->step_reachable) {
5077                                 warningf(&stmt->base.source_position, "statement is unreachable");
5078                         } else {
5079                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5080                                         warningf(&fors->initialisation->base.source_position,
5081                                                  "initialisation of for-statement is unreachable");
5082                                 }
5083
5084                                 if (!fors->condition_reachable && fors->condition != NULL) {
5085                                         warningf(&fors->condition->base.source_position,
5086                                                  "condition of for-statement is unreachable");
5087                                 }
5088
5089                                 if (!fors->step_reachable && fors->step != NULL) {
5090                                         warningf(&fors->step->base.source_position,
5091                                                  "step of for-statement is unreachable");
5092                                 }
5093                         }
5094
5095                         check_unreachable(stmt->fors.body);
5096                         break;
5097                 }
5098
5099                 case STATEMENT_MS_TRY:
5100                         panic("unimplemented");
5101         }
5102
5103         if (stmt->base.next)
5104                 check_unreachable(stmt->base.next);
5105 }
5106
5107 static void parse_external_declaration(void)
5108 {
5109         /* function-definitions and declarations both start with declaration
5110          * specifiers */
5111         declaration_specifiers_t specifiers;
5112         memset(&specifiers, 0, sizeof(specifiers));
5113
5114         add_anchor_token(';');
5115         parse_declaration_specifiers(&specifiers);
5116         rem_anchor_token(';');
5117
5118         /* must be a declaration */
5119         if (token.type == ';') {
5120                 parse_anonymous_declaration_rest(&specifiers, append_declaration);
5121                 return;
5122         }
5123
5124         add_anchor_token(',');
5125         add_anchor_token('=');
5126         rem_anchor_token(';');
5127
5128         /* declarator is common to both function-definitions and declarations */
5129         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5130
5131         rem_anchor_token(',');
5132         rem_anchor_token('=');
5133         rem_anchor_token(';');
5134
5135         /* must be a declaration */
5136         switch (token.type) {
5137                 case ',':
5138                 case ';':
5139                         parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
5140                         return;
5141
5142                 case '=':
5143                         parse_declaration_rest(ndeclaration, &specifiers, record_definition);
5144                         return;
5145         }
5146
5147         /* must be a function definition */
5148         parse_kr_declaration_list(ndeclaration);
5149
5150         if (token.type != '{') {
5151                 parse_error_expected("while parsing function definition", '{', NULL);
5152                 eat_until_matching_token(';');
5153                 return;
5154         }
5155
5156         type_t *type = ndeclaration->type;
5157
5158         /* note that we don't skip typerefs: the standard doesn't allow them here
5159          * (so we can't use is_type_function here) */
5160         if (type->kind != TYPE_FUNCTION) {
5161                 if (is_type_valid(type)) {
5162                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5163                                type, ndeclaration->symbol);
5164                 }
5165                 eat_block();
5166                 return;
5167         }
5168
5169         /* § 6.7.5.3 (14) a function definition with () means no
5170          * parameters (and not unspecified parameters) */
5171         if (type->function.unspecified_parameters
5172                         && type->function.parameters == NULL
5173                         && !type->function.kr_style_parameters) {
5174                 type_t *duplicate = duplicate_type(type);
5175                 duplicate->function.unspecified_parameters = false;
5176
5177                 type = typehash_insert(duplicate);
5178                 if (type != duplicate) {
5179                         obstack_free(type_obst, duplicate);
5180                 }
5181                 ndeclaration->type = type;
5182         }
5183
5184         declaration_t *const declaration = record_definition(ndeclaration);
5185         if (ndeclaration != declaration) {
5186                 declaration->scope = ndeclaration->scope;
5187         }
5188         type = skip_typeref(declaration->type);
5189
5190         /* push function parameters and switch scope */
5191         int       top        = environment_top();
5192         scope_t  *last_scope = scope;
5193         set_scope(&declaration->scope);
5194
5195         declaration_t *parameter = declaration->scope.declarations;
5196         for( ; parameter != NULL; parameter = parameter->next) {
5197                 if (parameter->parent_scope == &ndeclaration->scope) {
5198                         parameter->parent_scope = scope;
5199                 }
5200                 assert(parameter->parent_scope == NULL
5201                                 || parameter->parent_scope == scope);
5202                 parameter->parent_scope = scope;
5203                 if (parameter->symbol == NULL) {
5204                         errorf(&parameter->source_position, "parameter name omitted");
5205                         continue;
5206                 }
5207                 environment_push(parameter);
5208         }
5209
5210         if (declaration->init.statement != NULL) {
5211                 parser_error_multiple_definition(declaration, HERE);
5212                 eat_block();
5213         } else {
5214                 /* parse function body */
5215                 int            label_stack_top      = label_top();
5216                 declaration_t *old_current_function = current_function;
5217                 current_function                    = declaration;
5218                 current_parent                      = NULL;
5219
5220                 statement_t *const body = parse_compound_statement(false);
5221                 declaration->init.statement = body;
5222                 first_err = true;
5223                 check_labels();
5224                 check_declarations();
5225                 if (warning.return_type      ||
5226                     warning.unreachable_code ||
5227                     (warning.missing_noreturn && !(declaration->modifiers & DM_NORETURN))) {
5228                         noreturn_candidate = true;
5229                         check_reachable(body);
5230                         if (warning.unreachable_code)
5231                                 check_unreachable(body);
5232                         if (warning.missing_noreturn &&
5233                             noreturn_candidate       &&
5234                             !(declaration->modifiers & DM_NORETURN)) {
5235                                 warningf(&body->base.source_position,
5236                                          "function '%#T' is candidate for attribute 'noreturn'",
5237                                          type, declaration->symbol);
5238                         }
5239                 }
5240
5241                 assert(current_parent   == NULL);
5242                 assert(current_function == declaration);
5243                 current_function = old_current_function;
5244                 label_pop_to(label_stack_top);
5245         }
5246
5247         assert(scope == &declaration->scope);
5248         set_scope(last_scope);
5249         environment_pop_to(top);
5250 }
5251
5252 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5253                                   source_position_t *source_position)
5254 {
5255         type_t *type = allocate_type_zero(TYPE_BITFIELD, source_position);
5256
5257         type->bitfield.base_type = base_type;
5258         type->bitfield.size      = size;
5259
5260         return type;
5261 }
5262
5263 static declaration_t *find_compound_entry(declaration_t *compound_declaration,
5264                                           symbol_t *symbol)
5265 {
5266         declaration_t *iter = compound_declaration->scope.declarations;
5267         for( ; iter != NULL; iter = iter->next) {
5268                 if (iter->namespc != NAMESPACE_NORMAL)
5269                         continue;
5270
5271                 if (iter->symbol == NULL) {
5272                         type_t *type = skip_typeref(iter->type);
5273                         if (is_type_compound(type)) {
5274                                 declaration_t *result
5275                                         = find_compound_entry(type->compound.declaration, symbol);
5276                                 if (result != NULL)
5277                                         return result;
5278                         }
5279                         continue;
5280                 }
5281
5282                 if (iter->symbol == symbol) {
5283                         return iter;
5284                 }
5285         }
5286
5287         return NULL;
5288 }
5289
5290 static void parse_compound_declarators(declaration_t *struct_declaration,
5291                 const declaration_specifiers_t *specifiers)
5292 {
5293         declaration_t *last_declaration = struct_declaration->scope.declarations;
5294         if (last_declaration != NULL) {
5295                 while(last_declaration->next != NULL) {
5296                         last_declaration = last_declaration->next;
5297                 }
5298         }
5299
5300         while(1) {
5301                 declaration_t *declaration;
5302
5303                 if (token.type == ':') {
5304                         source_position_t source_position = *HERE;
5305                         next_token();
5306
5307                         type_t *base_type = specifiers->type;
5308                         expression_t *size = parse_constant_expression();
5309
5310                         if (!is_type_integer(skip_typeref(base_type))) {
5311                                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5312                                        base_type);
5313                         }
5314
5315                         type_t *type = make_bitfield_type(base_type, size, &source_position);
5316
5317                         declaration                         = allocate_declaration_zero();
5318                         declaration->namespc                = NAMESPACE_NORMAL;
5319                         declaration->declared_storage_class = STORAGE_CLASS_NONE;
5320                         declaration->storage_class          = STORAGE_CLASS_NONE;
5321                         declaration->source_position        = source_position;
5322                         declaration->modifiers              = specifiers->modifiers;
5323                         declaration->type                   = type;
5324                 } else {
5325                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
5326
5327                         type_t *orig_type = declaration->type;
5328                         type_t *type      = skip_typeref(orig_type);
5329
5330                         if (token.type == ':') {
5331                                 source_position_t source_position = *HERE;
5332                                 next_token();
5333                                 expression_t *size = parse_constant_expression();
5334
5335                                 if (!is_type_integer(type)) {
5336                                         errorf(HERE, "bitfield base type '%T' is not an "
5337                                                "integer type", orig_type);
5338                                 }
5339
5340                                 type_t *bitfield_type = make_bitfield_type(orig_type, size, &source_position);
5341                                 declaration->type = bitfield_type;
5342                         } else {
5343                                 /* TODO we ignore arrays for now... what is missing is a check
5344                                  * that they're at the end of the struct */
5345                                 if (is_type_incomplete(type) && !is_type_array(type)) {
5346                                         errorf(HERE,
5347                                                "compound member '%Y' has incomplete type '%T'",
5348                                                declaration->symbol, orig_type);
5349                                 } else if (is_type_function(type)) {
5350                                         errorf(HERE, "compound member '%Y' must not have function "
5351                                                "type '%T'", declaration->symbol, orig_type);
5352                                 }
5353                         }
5354                 }
5355
5356                 /* make sure we don't define a symbol multiple times */
5357                 symbol_t *symbol = declaration->symbol;
5358                 if (symbol != NULL) {
5359                         declaration_t *prev_decl
5360                                 = find_compound_entry(struct_declaration, symbol);
5361
5362                         if (prev_decl != NULL) {
5363                                 assert(prev_decl->symbol == symbol);
5364                                 errorf(&declaration->source_position,
5365                                        "multiple declarations of symbol '%Y' (declared %P)",
5366                                        symbol, &prev_decl->source_position);
5367                         }
5368                 }
5369
5370                 /* append declaration */
5371                 if (last_declaration != NULL) {
5372                         last_declaration->next = declaration;
5373                 } else {
5374                         struct_declaration->scope.declarations = declaration;
5375                 }
5376                 last_declaration = declaration;
5377
5378                 if (token.type != ',')
5379                         break;
5380                 next_token();
5381         }
5382         expect(';');
5383
5384 end_error:
5385         ;
5386 }
5387
5388 static void parse_compound_type_entries(declaration_t *compound_declaration)
5389 {
5390         eat('{');
5391         add_anchor_token('}');
5392
5393         while(token.type != '}' && token.type != T_EOF) {
5394                 declaration_specifiers_t specifiers;
5395                 memset(&specifiers, 0, sizeof(specifiers));
5396                 parse_declaration_specifiers(&specifiers);
5397
5398                 parse_compound_declarators(compound_declaration, &specifiers);
5399         }
5400         rem_anchor_token('}');
5401
5402         if (token.type == T_EOF) {
5403                 errorf(HERE, "EOF while parsing struct");
5404         }
5405         next_token();
5406 }
5407
5408 static type_t *parse_typename(void)
5409 {
5410         declaration_specifiers_t specifiers;
5411         memset(&specifiers, 0, sizeof(specifiers));
5412         parse_declaration_specifiers(&specifiers);
5413         if (specifiers.declared_storage_class != STORAGE_CLASS_NONE) {
5414                 /* TODO: improve error message, user does probably not know what a
5415                  * storage class is...
5416                  */
5417                 errorf(HERE, "typename may not have a storage class");
5418         }
5419
5420         type_t *result = parse_abstract_declarator(specifiers.type);
5421
5422         return result;
5423 }
5424
5425
5426
5427
5428 typedef expression_t* (*parse_expression_function) (unsigned precedence);
5429 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
5430                                                           expression_t *left);
5431
5432 typedef struct expression_parser_function_t expression_parser_function_t;
5433 struct expression_parser_function_t {
5434         unsigned                         precedence;
5435         parse_expression_function        parser;
5436         unsigned                         infix_precedence;
5437         parse_expression_infix_function  infix_parser;
5438 };
5439
5440 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5441
5442 /**
5443  * Prints an error message if an expression was expected but not read
5444  */
5445 static expression_t *expected_expression_error(void)
5446 {
5447         /* skip the error message if the error token was read */
5448         if (token.type != T_ERROR) {
5449                 errorf(HERE, "expected expression, got token '%K'", &token);
5450         }
5451         next_token();
5452
5453         return create_invalid_expression();
5454 }
5455
5456 /**
5457  * Parse a string constant.
5458  */
5459 static expression_t *parse_string_const(void)
5460 {
5461         wide_string_t wres;
5462         if (token.type == T_STRING_LITERAL) {
5463                 string_t res = token.v.string;
5464                 next_token();
5465                 while (token.type == T_STRING_LITERAL) {
5466                         res = concat_strings(&res, &token.v.string);
5467                         next_token();
5468                 }
5469                 if (token.type != T_WIDE_STRING_LITERAL) {
5470                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
5471                         /* note: that we use type_char_ptr here, which is already the
5472                          * automatic converted type. revert_automatic_type_conversion
5473                          * will construct the array type */
5474                         cnst->base.type    = type_char_ptr;
5475                         cnst->string.value = res;
5476                         return cnst;
5477                 }
5478
5479                 wres = concat_string_wide_string(&res, &token.v.wide_string);
5480         } else {
5481                 wres = token.v.wide_string;
5482         }
5483         next_token();
5484
5485         for (;;) {
5486                 switch (token.type) {
5487                         case T_WIDE_STRING_LITERAL:
5488                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
5489                                 break;
5490
5491                         case T_STRING_LITERAL:
5492                                 wres = concat_wide_string_string(&wres, &token.v.string);
5493                                 break;
5494
5495                         default: {
5496                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
5497                                 cnst->base.type         = type_wchar_t_ptr;
5498                                 cnst->wide_string.value = wres;
5499                                 return cnst;
5500                         }
5501                 }
5502                 next_token();
5503         }
5504 }
5505
5506 /**
5507  * Parse an integer constant.
5508  */
5509 static expression_t *parse_int_const(void)
5510 {
5511         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5512         cnst->base.source_position = *HERE;
5513         cnst->base.type            = token.datatype;
5514         cnst->conste.v.int_value   = token.v.intvalue;
5515
5516         next_token();
5517
5518         return cnst;
5519 }
5520
5521 /**
5522  * Parse a character constant.
5523  */
5524 static expression_t *parse_character_constant(void)
5525 {
5526         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
5527
5528         cnst->base.source_position = *HERE;
5529         cnst->base.type            = token.datatype;
5530         cnst->conste.v.character   = token.v.string;
5531
5532         if (cnst->conste.v.character.size != 1) {
5533                 if (warning.multichar && (c_mode & _GNUC)) {
5534                         /* TODO */
5535                         warningf(HERE, "multi-character character constant");
5536                 } else {
5537                         errorf(HERE, "more than 1 characters in character constant");
5538                 }
5539         }
5540         next_token();
5541
5542         return cnst;
5543 }
5544
5545 /**
5546  * Parse a wide character constant.
5547  */
5548 static expression_t *parse_wide_character_constant(void)
5549 {
5550         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
5551
5552         cnst->base.source_position    = *HERE;
5553         cnst->base.type               = token.datatype;
5554         cnst->conste.v.wide_character = token.v.wide_string;
5555
5556         if (cnst->conste.v.wide_character.size != 1) {
5557                 if (warning.multichar && (c_mode & _GNUC)) {
5558                         /* TODO */
5559                         warningf(HERE, "multi-character character constant");
5560                 } else {
5561                         errorf(HERE, "more than 1 characters in character constant");
5562                 }
5563         }
5564         next_token();
5565
5566         return cnst;
5567 }
5568
5569 /**
5570  * Parse a float constant.
5571  */
5572 static expression_t *parse_float_const(void)
5573 {
5574         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5575         cnst->base.type            = token.datatype;
5576         cnst->conste.v.float_value = token.v.floatvalue;
5577
5578         next_token();
5579
5580         return cnst;
5581 }
5582
5583 static declaration_t *create_implicit_function(symbol_t *symbol,
5584                 const source_position_t *source_position)
5585 {
5586         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION, source_position);
5587         ntype->function.return_type            = type_int;
5588         ntype->function.unspecified_parameters = true;
5589
5590         type_t *type = typehash_insert(ntype);
5591         if (type != ntype) {
5592                 free_type(ntype);
5593         }
5594
5595         declaration_t *const declaration    = allocate_declaration_zero();
5596         declaration->storage_class          = STORAGE_CLASS_EXTERN;
5597         declaration->declared_storage_class = STORAGE_CLASS_EXTERN;
5598         declaration->type                   = type;
5599         declaration->symbol                 = symbol;
5600         declaration->source_position        = *source_position;
5601
5602         bool strict_prototypes_old = warning.strict_prototypes;
5603         warning.strict_prototypes  = false;
5604         record_declaration(declaration);
5605         warning.strict_prototypes = strict_prototypes_old;
5606
5607         return declaration;
5608 }
5609
5610 /**
5611  * Creates a return_type (func)(argument_type) function type if not
5612  * already exists.
5613  */
5614 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
5615                                     type_t *argument_type2)
5616 {
5617         function_parameter_t *parameter2
5618                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
5619         memset(parameter2, 0, sizeof(parameter2[0]));
5620         parameter2->type = argument_type2;
5621
5622         function_parameter_t *parameter1
5623                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
5624         memset(parameter1, 0, sizeof(parameter1[0]));
5625         parameter1->type = argument_type1;
5626         parameter1->next = parameter2;
5627
5628         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5629         type->function.return_type = return_type;
5630         type->function.parameters  = parameter1;
5631
5632         type_t *result = typehash_insert(type);
5633         if (result != type) {
5634                 free_type(type);
5635         }
5636
5637         return result;
5638 }
5639
5640 /**
5641  * Creates a return_type (func)(argument_type) function type if not
5642  * already exists.
5643  *
5644  * @param return_type    the return type
5645  * @param argument_type  the argument type
5646  */
5647 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
5648 {
5649         function_parameter_t *parameter
5650                 = obstack_alloc(type_obst, sizeof(parameter[0]));
5651         memset(parameter, 0, sizeof(parameter[0]));
5652         parameter->type = argument_type;
5653
5654         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5655         type->function.return_type = return_type;
5656         type->function.parameters  = parameter;
5657
5658         type_t *result = typehash_insert(type);
5659         if (result != type) {
5660                 free_type(type);
5661         }
5662
5663         return result;
5664 }
5665
5666 static type_t *make_function_0_type(type_t *return_type)
5667 {
5668         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5669         type->function.return_type = return_type;
5670         type->function.parameters  = NULL;
5671
5672         type_t *result = typehash_insert(type);
5673         if (result != type) {
5674                 free_type(type);
5675         }
5676
5677         return result;
5678 }
5679
5680 /**
5681  * Creates a function type for some function like builtins.
5682  *
5683  * @param symbol   the symbol describing the builtin
5684  */
5685 static type_t *get_builtin_symbol_type(symbol_t *symbol)
5686 {
5687         switch(symbol->ID) {
5688         case T___builtin_alloca:
5689                 return make_function_1_type(type_void_ptr, type_size_t);
5690         case T___builtin_huge_val:
5691                 return make_function_0_type(type_double);
5692         case T___builtin_nan:
5693                 return make_function_1_type(type_double, type_char_ptr);
5694         case T___builtin_nanf:
5695                 return make_function_1_type(type_float, type_char_ptr);
5696         case T___builtin_nand:
5697                 return make_function_1_type(type_long_double, type_char_ptr);
5698         case T___builtin_va_end:
5699                 return make_function_1_type(type_void, type_valist);
5700         case T___builtin_expect:
5701                 return make_function_2_type(type_long, type_long, type_long);
5702         default:
5703                 internal_errorf(HERE, "not implemented builtin symbol found");
5704         }
5705 }
5706
5707 /**
5708  * Performs automatic type cast as described in § 6.3.2.1.
5709  *
5710  * @param orig_type  the original type
5711  */
5712 static type_t *automatic_type_conversion(type_t *orig_type)
5713 {
5714         type_t *type = skip_typeref(orig_type);
5715         if (is_type_array(type)) {
5716                 array_type_t *array_type   = &type->array;
5717                 type_t       *element_type = array_type->element_type;
5718                 unsigned      qualifiers   = array_type->base.qualifiers;
5719
5720                 return make_pointer_type(element_type, qualifiers);
5721         }
5722
5723         if (is_type_function(type)) {
5724                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
5725         }
5726
5727         return orig_type;
5728 }
5729
5730 /**
5731  * reverts the automatic casts of array to pointer types and function
5732  * to function-pointer types as defined § 6.3.2.1
5733  */
5734 type_t *revert_automatic_type_conversion(const expression_t *expression)
5735 {
5736         switch (expression->kind) {
5737                 case EXPR_REFERENCE: return expression->reference.declaration->type;
5738                 case EXPR_SELECT:    return expression->select.compound_entry->type;
5739
5740                 case EXPR_UNARY_DEREFERENCE: {
5741                         const expression_t *const value = expression->unary.value;
5742                         type_t             *const type  = skip_typeref(value->base.type);
5743                         assert(is_type_pointer(type));
5744                         return type->pointer.points_to;
5745                 }
5746
5747                 case EXPR_BUILTIN_SYMBOL:
5748                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
5749
5750                 case EXPR_ARRAY_ACCESS: {
5751                         const expression_t *array_ref = expression->array_access.array_ref;
5752                         type_t             *type_left = skip_typeref(array_ref->base.type);
5753                         if (!is_type_valid(type_left))
5754                                 return type_left;
5755                         assert(is_type_pointer(type_left));
5756                         return type_left->pointer.points_to;
5757                 }
5758
5759                 case EXPR_STRING_LITERAL: {
5760                         size_t size = expression->string.value.size;
5761                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
5762                 }
5763
5764                 case EXPR_WIDE_STRING_LITERAL: {
5765                         size_t size = expression->wide_string.value.size;
5766                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
5767                 }
5768
5769                 case EXPR_COMPOUND_LITERAL:
5770                         return expression->compound_literal.type;
5771
5772                 default: break;
5773         }
5774
5775         return expression->base.type;
5776 }
5777
5778 static expression_t *parse_reference(void)
5779 {
5780         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
5781
5782         reference_expression_t *ref = &expression->reference;
5783         symbol_t *const symbol = token.v.symbol;
5784
5785         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
5786
5787         source_position_t source_position = token.source_position;
5788         next_token();
5789
5790         if (declaration == NULL) {
5791                 if (! strict_mode && token.type == '(') {
5792                         /* an implicitly defined function */
5793                         if (warning.implicit_function_declaration) {
5794                                 warningf(HERE, "implicit declaration of function '%Y'",
5795                                         symbol);
5796                         }
5797
5798                         declaration = create_implicit_function(symbol,
5799                                                                &source_position);
5800                 } else {
5801                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
5802                         return create_invalid_expression();
5803                 }
5804         }
5805
5806         type_t *type         = declaration->type;
5807
5808         /* we always do the auto-type conversions; the & and sizeof parser contains
5809          * code to revert this! */
5810         type = automatic_type_conversion(type);
5811
5812         ref->declaration = declaration;
5813         ref->base.type   = type;
5814
5815         /* this declaration is used */
5816         declaration->used = true;
5817
5818         /* check for deprecated functions */
5819         if (warning.deprecated_declarations &&
5820             declaration->modifiers & DM_DEPRECATED) {
5821                 char const *const prefix = is_type_function(declaration->type) ?
5822                         "function" : "variable";
5823
5824                 if (declaration->deprecated_string != NULL) {
5825                         warningf(&source_position,
5826                                 "%s '%Y' is deprecated (declared %P): \"%s\"", prefix,
5827                                 declaration->symbol, &declaration->source_position,
5828                                 declaration->deprecated_string);
5829                 } else {
5830                         warningf(&source_position,
5831                                 "%s '%Y' is deprecated (declared %P)", prefix,
5832                                 declaration->symbol, &declaration->source_position);
5833                 }
5834         }
5835
5836         return expression;
5837 }
5838
5839 static void check_cast_allowed(expression_t *expression, type_t *dest_type)
5840 {
5841         (void) expression;
5842         (void) dest_type;
5843         /* TODO check if explicit cast is allowed and issue warnings/errors */
5844 }
5845
5846 static expression_t *parse_compound_literal(type_t *type)
5847 {
5848         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
5849
5850         parse_initializer_env_t env;
5851         env.type             = type;
5852         env.declaration      = NULL;
5853         env.must_be_constant = false;
5854         initializer_t *initializer = parse_initializer(&env);
5855         type = env.type;
5856
5857         expression->compound_literal.initializer = initializer;
5858         expression->compound_literal.type        = type;
5859         expression->base.type                    = automatic_type_conversion(type);
5860
5861         return expression;
5862 }
5863
5864 /**
5865  * Parse a cast expression.
5866  */
5867 static expression_t *parse_cast(void)
5868 {
5869         source_position_t source_position = token.source_position;
5870
5871         type_t *type  = parse_typename();
5872
5873         /* matching add_anchor_token() is at call site */
5874         rem_anchor_token(')');
5875         expect(')');
5876
5877         if (token.type == '{') {
5878                 return parse_compound_literal(type);
5879         }
5880
5881         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
5882         cast->base.source_position = source_position;
5883
5884         expression_t *value = parse_sub_expression(20);
5885
5886         check_cast_allowed(value, type);
5887
5888         cast->base.type   = type;
5889         cast->unary.value = value;
5890
5891         return cast;
5892 end_error:
5893         return create_invalid_expression();
5894 }
5895
5896 /**
5897  * Parse a statement expression.
5898  */
5899 static expression_t *parse_statement_expression(void)
5900 {
5901         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
5902
5903         statement_t *statement           = parse_compound_statement(true);
5904         expression->statement.statement  = statement;
5905         expression->base.source_position = statement->base.source_position;
5906
5907         /* find last statement and use its type */
5908         type_t *type = type_void;
5909         const statement_t *stmt = statement->compound.statements;
5910         if (stmt != NULL) {
5911                 while (stmt->base.next != NULL)
5912                         stmt = stmt->base.next;
5913
5914                 if (stmt->kind == STATEMENT_EXPRESSION) {
5915                         type = stmt->expression.expression->base.type;
5916                 }
5917         } else {
5918                 warningf(&expression->base.source_position, "empty statement expression ({})");
5919         }
5920         expression->base.type = type;
5921
5922         expect(')');
5923
5924         return expression;
5925 end_error:
5926         return create_invalid_expression();
5927 }
5928
5929 /**
5930  * Parse a braced expression.
5931  */
5932 static expression_t *parse_brace_expression(void)
5933 {
5934         eat('(');
5935         add_anchor_token(')');
5936
5937         switch(token.type) {
5938         case '{':
5939                 /* gcc extension: a statement expression */
5940                 return parse_statement_expression();
5941
5942         TYPE_QUALIFIERS
5943         TYPE_SPECIFIERS
5944                 return parse_cast();
5945         case T_IDENTIFIER:
5946                 if (is_typedef_symbol(token.v.symbol)) {
5947                         return parse_cast();
5948                 }
5949         }
5950
5951         expression_t *result = parse_expression();
5952         rem_anchor_token(')');
5953         expect(')');
5954
5955         return result;
5956 end_error:
5957         return create_invalid_expression();
5958 }
5959
5960 static expression_t *parse_function_keyword(void)
5961 {
5962         next_token();
5963         /* TODO */
5964
5965         if (current_function == NULL) {
5966                 errorf(HERE, "'__func__' used outside of a function");
5967         }
5968
5969         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5970         expression->base.type     = type_char_ptr;
5971         expression->funcname.kind = FUNCNAME_FUNCTION;
5972
5973         return expression;
5974 }
5975
5976 static expression_t *parse_pretty_function_keyword(void)
5977 {
5978         eat(T___PRETTY_FUNCTION__);
5979
5980         if (current_function == NULL) {
5981                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
5982         }
5983
5984         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5985         expression->base.type     = type_char_ptr;
5986         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
5987
5988         return expression;
5989 }
5990
5991 static expression_t *parse_funcsig_keyword(void)
5992 {
5993         eat(T___FUNCSIG__);
5994
5995         if (current_function == NULL) {
5996                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
5997         }
5998
5999         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6000         expression->base.type     = type_char_ptr;
6001         expression->funcname.kind = FUNCNAME_FUNCSIG;
6002
6003         return expression;
6004 }
6005
6006 static expression_t *parse_funcdname_keyword(void)
6007 {
6008         eat(T___FUNCDNAME__);
6009
6010         if (current_function == NULL) {
6011                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6012         }
6013
6014         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6015         expression->base.type     = type_char_ptr;
6016         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6017
6018         return expression;
6019 }
6020
6021 static designator_t *parse_designator(void)
6022 {
6023         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6024         result->source_position = *HERE;
6025
6026         if (token.type != T_IDENTIFIER) {
6027                 parse_error_expected("while parsing member designator",
6028                                      T_IDENTIFIER, NULL);
6029                 return NULL;
6030         }
6031         result->symbol = token.v.symbol;
6032         next_token();
6033
6034         designator_t *last_designator = result;
6035         while(true) {
6036                 if (token.type == '.') {
6037                         next_token();
6038                         if (token.type != T_IDENTIFIER) {
6039                                 parse_error_expected("while parsing member designator",
6040                                                      T_IDENTIFIER, NULL);
6041                                 return NULL;
6042                         }
6043                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6044                         designator->source_position = *HERE;
6045                         designator->symbol          = token.v.symbol;
6046                         next_token();
6047
6048                         last_designator->next = designator;
6049                         last_designator       = designator;
6050                         continue;
6051                 }
6052                 if (token.type == '[') {
6053                         next_token();
6054                         add_anchor_token(']');
6055                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6056                         designator->source_position = *HERE;
6057                         designator->array_index     = parse_expression();
6058                         rem_anchor_token(']');
6059                         expect(']');
6060                         if (designator->array_index == NULL) {
6061                                 return NULL;
6062                         }
6063
6064                         last_designator->next = designator;
6065                         last_designator       = designator;
6066                         continue;
6067                 }
6068                 break;
6069         }
6070
6071         return result;
6072 end_error:
6073         return NULL;
6074 }
6075
6076 /**
6077  * Parse the __builtin_offsetof() expression.
6078  */
6079 static expression_t *parse_offsetof(void)
6080 {
6081         eat(T___builtin_offsetof);
6082
6083         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6084         expression->base.type    = type_size_t;
6085
6086         expect('(');
6087         add_anchor_token(',');
6088         type_t *type = parse_typename();
6089         rem_anchor_token(',');
6090         expect(',');
6091         add_anchor_token(')');
6092         designator_t *designator = parse_designator();
6093         rem_anchor_token(')');
6094         expect(')');
6095
6096         expression->offsetofe.type       = type;
6097         expression->offsetofe.designator = designator;
6098
6099         type_path_t path;
6100         memset(&path, 0, sizeof(path));
6101         path.top_type = type;
6102         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6103
6104         descend_into_subtype(&path);
6105
6106         if (!walk_designator(&path, designator, true)) {
6107                 return create_invalid_expression();
6108         }
6109
6110         DEL_ARR_F(path.path);
6111
6112         return expression;
6113 end_error:
6114         return create_invalid_expression();
6115 }
6116
6117 /**
6118  * Parses a _builtin_va_start() expression.
6119  */
6120 static expression_t *parse_va_start(void)
6121 {
6122         eat(T___builtin_va_start);
6123
6124         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6125
6126         expect('(');
6127         add_anchor_token(',');
6128         expression->va_starte.ap = parse_assignment_expression();
6129         rem_anchor_token(',');
6130         expect(',');
6131         expression_t *const expr = parse_assignment_expression();
6132         if (expr->kind == EXPR_REFERENCE) {
6133                 declaration_t *const decl = expr->reference.declaration;
6134                 if (decl == NULL)
6135                         return create_invalid_expression();
6136                 if (decl->parent_scope == &current_function->scope &&
6137                     decl->next == NULL) {
6138                         expression->va_starte.parameter = decl;
6139                         expect(')');
6140                         return expression;
6141                 }
6142         }
6143         errorf(&expr->base.source_position,
6144                "second argument of 'va_start' must be last parameter of the current function");
6145 end_error:
6146         return create_invalid_expression();
6147 }
6148
6149 /**
6150  * Parses a _builtin_va_arg() expression.
6151  */
6152 static expression_t *parse_va_arg(void)
6153 {
6154         eat(T___builtin_va_arg);
6155
6156         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6157
6158         expect('(');
6159         expression->va_arge.ap = parse_assignment_expression();
6160         expect(',');
6161         expression->base.type = parse_typename();
6162         expect(')');
6163
6164         return expression;
6165 end_error:
6166         return create_invalid_expression();
6167 }
6168
6169 static expression_t *parse_builtin_symbol(void)
6170 {
6171         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
6172
6173         symbol_t *symbol = token.v.symbol;
6174
6175         expression->builtin_symbol.symbol = symbol;
6176         next_token();
6177
6178         type_t *type = get_builtin_symbol_type(symbol);
6179         type = automatic_type_conversion(type);
6180
6181         expression->base.type = type;
6182         return expression;
6183 }
6184
6185 /**
6186  * Parses a __builtin_constant() expression.
6187  */
6188 static expression_t *parse_builtin_constant(void)
6189 {
6190         eat(T___builtin_constant_p);
6191
6192         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6193
6194         expect('(');
6195         add_anchor_token(')');
6196         expression->builtin_constant.value = parse_assignment_expression();
6197         rem_anchor_token(')');
6198         expect(')');
6199         expression->base.type = type_int;
6200
6201         return expression;
6202 end_error:
6203         return create_invalid_expression();
6204 }
6205
6206 /**
6207  * Parses a __builtin_prefetch() expression.
6208  */
6209 static expression_t *parse_builtin_prefetch(void)
6210 {
6211         eat(T___builtin_prefetch);
6212
6213         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
6214
6215         expect('(');
6216         add_anchor_token(')');
6217         expression->builtin_prefetch.adr = parse_assignment_expression();
6218         if (token.type == ',') {
6219                 next_token();
6220                 expression->builtin_prefetch.rw = parse_assignment_expression();
6221         }
6222         if (token.type == ',') {
6223                 next_token();
6224                 expression->builtin_prefetch.locality = parse_assignment_expression();
6225         }
6226         rem_anchor_token(')');
6227         expect(')');
6228         expression->base.type = type_void;
6229
6230         return expression;
6231 end_error:
6232         return create_invalid_expression();
6233 }
6234
6235 /**
6236  * Parses a __builtin_is_*() compare expression.
6237  */
6238 static expression_t *parse_compare_builtin(void)
6239 {
6240         expression_t *expression;
6241
6242         switch(token.type) {
6243         case T___builtin_isgreater:
6244                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6245                 break;
6246         case T___builtin_isgreaterequal:
6247                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6248                 break;
6249         case T___builtin_isless:
6250                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6251                 break;
6252         case T___builtin_islessequal:
6253                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6254                 break;
6255         case T___builtin_islessgreater:
6256                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6257                 break;
6258         case T___builtin_isunordered:
6259                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6260                 break;
6261         default:
6262                 internal_errorf(HERE, "invalid compare builtin found");
6263                 break;
6264         }
6265         expression->base.source_position = *HERE;
6266         next_token();
6267
6268         expect('(');
6269         expression->binary.left = parse_assignment_expression();
6270         expect(',');
6271         expression->binary.right = parse_assignment_expression();
6272         expect(')');
6273
6274         type_t *const orig_type_left  = expression->binary.left->base.type;
6275         type_t *const orig_type_right = expression->binary.right->base.type;
6276
6277         type_t *const type_left  = skip_typeref(orig_type_left);
6278         type_t *const type_right = skip_typeref(orig_type_right);
6279         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6280                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6281                         type_error_incompatible("invalid operands in comparison",
6282                                 &expression->base.source_position, orig_type_left, orig_type_right);
6283                 }
6284         } else {
6285                 semantic_comparison(&expression->binary);
6286         }
6287
6288         return expression;
6289 end_error:
6290         return create_invalid_expression();
6291 }
6292
6293 #if 0
6294 /**
6295  * Parses a __builtin_expect() expression.
6296  */
6297 static expression_t *parse_builtin_expect(void)
6298 {
6299         eat(T___builtin_expect);
6300
6301         expression_t *expression
6302                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
6303
6304         expect('(');
6305         expression->binary.left = parse_assignment_expression();
6306         expect(',');
6307         expression->binary.right = parse_constant_expression();
6308         expect(')');
6309
6310         expression->base.type = expression->binary.left->base.type;
6311
6312         return expression;
6313 end_error:
6314         return create_invalid_expression();
6315 }
6316 #endif
6317
6318 /**
6319  * Parses a MS assume() expression.
6320  */
6321 static expression_t *parse_assume(void)
6322 {
6323         eat(T__assume);
6324
6325         expression_t *expression
6326                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
6327
6328         expect('(');
6329         add_anchor_token(')');
6330         expression->unary.value = parse_assignment_expression();
6331         rem_anchor_token(')');
6332         expect(')');
6333
6334         expression->base.type = type_void;
6335         return expression;
6336 end_error:
6337         return create_invalid_expression();
6338 }
6339
6340 /**
6341  * Parse a microsoft __noop expression.
6342  */
6343 static expression_t *parse_noop_expression(void)
6344 {
6345         source_position_t source_position = *HERE;
6346         eat(T___noop);
6347
6348         if (token.type == '(') {
6349                 /* parse arguments */
6350                 eat('(');
6351                 add_anchor_token(')');
6352                 add_anchor_token(',');
6353
6354                 if (token.type != ')') {
6355                         while(true) {
6356                                 (void)parse_assignment_expression();
6357                                 if (token.type != ',')
6358                                         break;
6359                                 next_token();
6360                         }
6361                 }
6362         }
6363         rem_anchor_token(',');
6364         rem_anchor_token(')');
6365         expect(')');
6366
6367         /* the result is a (int)0 */
6368         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6369         cnst->base.source_position = source_position;
6370         cnst->base.type            = type_int;
6371         cnst->conste.v.int_value   = 0;
6372         cnst->conste.is_ms_noop    = true;
6373
6374         return cnst;
6375
6376 end_error:
6377         return create_invalid_expression();
6378 }
6379
6380 /**
6381  * Parses a primary expression.
6382  */
6383 static expression_t *parse_primary_expression(void)
6384 {
6385         switch (token.type) {
6386                 case T_INTEGER:                  return parse_int_const();
6387                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
6388                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
6389                 case T_FLOATINGPOINT:            return parse_float_const();
6390                 case T_STRING_LITERAL:
6391                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
6392                 case T_IDENTIFIER:               return parse_reference();
6393                 case T___FUNCTION__:
6394                 case T___func__:                 return parse_function_keyword();
6395                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
6396                 case T___FUNCSIG__:              return parse_funcsig_keyword();
6397                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
6398                 case T___builtin_offsetof:       return parse_offsetof();
6399                 case T___builtin_va_start:       return parse_va_start();
6400                 case T___builtin_va_arg:         return parse_va_arg();
6401                 case T___builtin_expect:
6402                 case T___builtin_alloca:
6403                 case T___builtin_nan:
6404                 case T___builtin_nand:
6405                 case T___builtin_nanf:
6406                 case T___builtin_huge_val:
6407                 case T___builtin_va_end:         return parse_builtin_symbol();
6408                 case T___builtin_isgreater:
6409                 case T___builtin_isgreaterequal:
6410                 case T___builtin_isless:
6411                 case T___builtin_islessequal:
6412                 case T___builtin_islessgreater:
6413                 case T___builtin_isunordered:    return parse_compare_builtin();
6414                 case T___builtin_constant_p:     return parse_builtin_constant();
6415                 case T___builtin_prefetch:       return parse_builtin_prefetch();
6416                 case T__assume:                  return parse_assume();
6417
6418                 case '(':                        return parse_brace_expression();
6419                 case T___noop:                   return parse_noop_expression();
6420         }
6421
6422         errorf(HERE, "unexpected token %K, expected an expression", &token);
6423         return create_invalid_expression();
6424 }
6425
6426 /**
6427  * Check if the expression has the character type and issue a warning then.
6428  */
6429 static void check_for_char_index_type(const expression_t *expression)
6430 {
6431         type_t       *const type      = expression->base.type;
6432         const type_t *const base_type = skip_typeref(type);
6433
6434         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
6435                         warning.char_subscripts) {
6436                 warningf(&expression->base.source_position,
6437                          "array subscript has type '%T'", type);
6438         }
6439 }
6440
6441 static expression_t *parse_array_expression(unsigned precedence,
6442                                             expression_t *left)
6443 {
6444         (void) precedence;
6445
6446         eat('[');
6447         add_anchor_token(']');
6448
6449         expression_t *inside = parse_expression();
6450
6451         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
6452
6453         array_access_expression_t *array_access = &expression->array_access;
6454
6455         type_t *const orig_type_left   = left->base.type;
6456         type_t *const orig_type_inside = inside->base.type;
6457
6458         type_t *const type_left   = skip_typeref(orig_type_left);
6459         type_t *const type_inside = skip_typeref(orig_type_inside);
6460
6461         type_t *return_type;
6462         if (is_type_pointer(type_left)) {
6463                 return_type             = type_left->pointer.points_to;
6464                 array_access->array_ref = left;
6465                 array_access->index     = inside;
6466                 check_for_char_index_type(inside);
6467         } else if (is_type_pointer(type_inside)) {
6468                 return_type             = type_inside->pointer.points_to;
6469                 array_access->array_ref = inside;
6470                 array_access->index     = left;
6471                 array_access->flipped   = true;
6472                 check_for_char_index_type(left);
6473         } else {
6474                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
6475                         errorf(HERE,
6476                                 "array access on object with non-pointer types '%T', '%T'",
6477                                 orig_type_left, orig_type_inside);
6478                 }
6479                 return_type             = type_error_type;
6480                 array_access->array_ref = create_invalid_expression();
6481         }
6482
6483         rem_anchor_token(']');
6484         if (token.type != ']') {
6485                 parse_error_expected("Problem while parsing array access", ']', NULL);
6486                 return expression;
6487         }
6488         next_token();
6489
6490         return_type           = automatic_type_conversion(return_type);
6491         expression->base.type = return_type;
6492
6493         return expression;
6494 }
6495
6496 static expression_t *parse_typeprop(expression_kind_t const kind,
6497                                     source_position_t const pos,
6498                                     unsigned const precedence)
6499 {
6500         expression_t *tp_expression = allocate_expression_zero(kind);
6501         tp_expression->base.type            = type_size_t;
6502         tp_expression->base.source_position = pos;
6503
6504         char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
6505
6506         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
6507                 next_token();
6508                 add_anchor_token(')');
6509                 type_t* const orig_type = parse_typename();
6510                 tp_expression->typeprop.type = orig_type;
6511
6512                 type_t const* const type = skip_typeref(orig_type);
6513                 char const* const wrong_type =
6514                         is_type_incomplete(type)    ? "incomplete"          :
6515                         type->kind == TYPE_FUNCTION ? "function designator" :
6516                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6517                         NULL;
6518                 if (wrong_type != NULL) {
6519                         errorf(&pos, "operand of %s expression must not be %s type '%T'",
6520                                what, wrong_type, type);
6521                 }
6522
6523                 rem_anchor_token(')');
6524                 expect(')');
6525         } else {
6526                 expression_t *expression = parse_sub_expression(precedence);
6527
6528                 type_t* const orig_type = revert_automatic_type_conversion(expression);
6529                 expression->base.type = orig_type;
6530
6531                 type_t const* const type = skip_typeref(orig_type);
6532                 char const* const wrong_type =
6533                         is_type_incomplete(type)    ? "incomplete"          :
6534                         type->kind == TYPE_FUNCTION ? "function designator" :
6535                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6536                         NULL;
6537                 if (wrong_type != NULL) {
6538                         errorf(&pos, "operand of %s expression must not be expression of %s type '%T'", what, wrong_type, type);
6539                 }
6540
6541                 tp_expression->typeprop.type          = expression->base.type;
6542                 tp_expression->typeprop.tp_expression = expression;
6543         }
6544
6545         return tp_expression;
6546 end_error:
6547         return create_invalid_expression();
6548 }
6549
6550 static expression_t *parse_sizeof(unsigned precedence)
6551 {
6552         source_position_t pos = *HERE;
6553         eat(T_sizeof);
6554         return parse_typeprop(EXPR_SIZEOF, pos, precedence);
6555 }
6556
6557 static expression_t *parse_alignof(unsigned precedence)
6558 {
6559         source_position_t pos = *HERE;
6560         eat(T___alignof__);
6561         return parse_typeprop(EXPR_ALIGNOF, pos, precedence);
6562 }
6563
6564 static expression_t *parse_select_expression(unsigned precedence,
6565                                              expression_t *compound)
6566 {
6567         (void) precedence;
6568         assert(token.type == '.' || token.type == T_MINUSGREATER);
6569
6570         bool is_pointer = (token.type == T_MINUSGREATER);
6571         next_token();
6572
6573         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
6574         select->select.compound = compound;
6575
6576         if (token.type != T_IDENTIFIER) {
6577                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
6578                 return select;
6579         }
6580         symbol_t *symbol      = token.v.symbol;
6581         select->select.symbol = symbol;
6582         next_token();
6583
6584         type_t *const orig_type = compound->base.type;
6585         type_t *const type      = skip_typeref(orig_type);
6586
6587         type_t *type_left = type;
6588         if (is_pointer) {
6589                 if (!is_type_pointer(type)) {
6590                         if (is_type_valid(type)) {
6591                                 errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
6592                         }
6593                         return create_invalid_expression();
6594                 }
6595                 type_left = type->pointer.points_to;
6596         }
6597         type_left = skip_typeref(type_left);
6598
6599         if (type_left->kind != TYPE_COMPOUND_STRUCT &&
6600             type_left->kind != TYPE_COMPOUND_UNION) {
6601                 if (is_type_valid(type_left)) {
6602                         errorf(HERE, "request for member '%Y' in something not a struct or "
6603                                "union, but '%T'", symbol, type_left);
6604                 }
6605                 return create_invalid_expression();
6606         }
6607
6608         declaration_t *const declaration = type_left->compound.declaration;
6609
6610         if (!declaration->init.complete) {
6611                 errorf(HERE, "request for member '%Y' of incomplete type '%T'",
6612                        symbol, type_left);
6613                 return create_invalid_expression();
6614         }
6615
6616         declaration_t *iter = find_compound_entry(declaration, symbol);
6617         if (iter == NULL) {
6618                 errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
6619                 return create_invalid_expression();
6620         }
6621
6622         /* we always do the auto-type conversions; the & and sizeof parser contains
6623          * code to revert this! */
6624         type_t *expression_type = automatic_type_conversion(iter->type);
6625
6626         select->select.compound_entry = iter;
6627         select->base.type             = expression_type;
6628
6629         type_t *skipped = skip_typeref(iter->type);
6630         if (skipped->kind == TYPE_BITFIELD) {
6631                 select->base.type = skipped->bitfield.base_type;
6632         }
6633
6634         return select;
6635 }
6636
6637 static void check_call_argument(const function_parameter_t *parameter,
6638                                 call_argument_t *argument)
6639 {
6640         type_t         *expected_type      = parameter->type;
6641         type_t         *expected_type_skip = skip_typeref(expected_type);
6642         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
6643         expression_t   *arg_expr           = argument->expression;
6644
6645         /* handle transparent union gnu extension */
6646         if (is_type_union(expected_type_skip)
6647                         && (expected_type_skip->base.modifiers
6648                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
6649                 declaration_t  *union_decl = expected_type_skip->compound.declaration;
6650
6651                 declaration_t *declaration = union_decl->scope.declarations;
6652                 type_t        *best_type   = NULL;
6653                 for ( ; declaration != NULL; declaration = declaration->next) {
6654                         type_t *decl_type = declaration->type;
6655                         error = semantic_assign(decl_type, arg_expr);
6656                         if (error == ASSIGN_ERROR_INCOMPATIBLE
6657                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
6658                                 continue;
6659
6660                         if (error == ASSIGN_SUCCESS) {
6661                                 best_type = decl_type;
6662                         } else if (best_type == NULL) {
6663                                 best_type = decl_type;
6664                         }
6665                 }
6666
6667                 if (best_type != NULL) {
6668                         expected_type = best_type;
6669                 }
6670         }
6671
6672         error                = semantic_assign(expected_type, arg_expr);
6673         argument->expression = create_implicit_cast(argument->expression,
6674                                                     expected_type);
6675
6676         /* TODO report exact scope in error messages (like "in 3rd parameter") */
6677         report_assign_error(error, expected_type, arg_expr,     "function call",
6678                             &arg_expr->base.source_position);
6679 }
6680
6681 /**
6682  * Parse a call expression, ie. expression '( ... )'.
6683  *
6684  * @param expression  the function address
6685  */
6686 static expression_t *parse_call_expression(unsigned precedence,
6687                                            expression_t *expression)
6688 {
6689         (void) precedence;
6690         expression_t *result = allocate_expression_zero(EXPR_CALL);
6691         result->base.source_position = expression->base.source_position;
6692
6693         call_expression_t *call = &result->call;
6694         call->function          = expression;
6695
6696         type_t *const orig_type = expression->base.type;
6697         type_t *const type      = skip_typeref(orig_type);
6698
6699         function_type_t *function_type = NULL;
6700         if (is_type_pointer(type)) {
6701                 type_t *const to_type = skip_typeref(type->pointer.points_to);
6702
6703                 if (is_type_function(to_type)) {
6704                         function_type   = &to_type->function;
6705                         call->base.type = function_type->return_type;
6706                 }
6707         }
6708
6709         if (function_type == NULL && is_type_valid(type)) {
6710                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
6711         }
6712
6713         /* parse arguments */
6714         eat('(');
6715         add_anchor_token(')');
6716         add_anchor_token(',');
6717
6718         if (token.type != ')') {
6719                 call_argument_t *last_argument = NULL;
6720
6721                 while(true) {
6722                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
6723
6724                         argument->expression = parse_assignment_expression();
6725                         if (last_argument == NULL) {
6726                                 call->arguments = argument;
6727                         } else {
6728                                 last_argument->next = argument;
6729                         }
6730                         last_argument = argument;
6731
6732                         if (token.type != ',')
6733                                 break;
6734                         next_token();
6735                 }
6736         }
6737         rem_anchor_token(',');
6738         rem_anchor_token(')');
6739         expect(')');
6740
6741         if (function_type == NULL)
6742                 return result;
6743
6744         function_parameter_t *parameter = function_type->parameters;
6745         call_argument_t      *argument  = call->arguments;
6746         if (!function_type->unspecified_parameters) {
6747                 for( ; parameter != NULL && argument != NULL;
6748                                 parameter = parameter->next, argument = argument->next) {
6749                         check_call_argument(parameter, argument);
6750                 }
6751
6752                 if (parameter != NULL) {
6753                         errorf(HERE, "too few arguments to function '%E'", expression);
6754                 } else if (argument != NULL && !function_type->variadic) {
6755                         errorf(HERE, "too many arguments to function '%E'", expression);
6756                 }
6757         }
6758
6759         /* do default promotion */
6760         for( ; argument != NULL; argument = argument->next) {
6761                 type_t *type = argument->expression->base.type;
6762
6763                 type = get_default_promoted_type(type);
6764
6765                 argument->expression
6766                         = create_implicit_cast(argument->expression, type);
6767         }
6768
6769         check_format(&result->call);
6770
6771         return result;
6772 end_error:
6773         return create_invalid_expression();
6774 }
6775
6776 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
6777
6778 static bool same_compound_type(const type_t *type1, const type_t *type2)
6779 {
6780         return
6781                 is_type_compound(type1) &&
6782                 type1->kind == type2->kind &&
6783                 type1->compound.declaration == type2->compound.declaration;
6784 }
6785
6786 /**
6787  * Parse a conditional expression, ie. 'expression ? ... : ...'.
6788  *
6789  * @param expression  the conditional expression
6790  */
6791 static expression_t *parse_conditional_expression(unsigned precedence,
6792                                                   expression_t *expression)
6793 {
6794         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
6795
6796         conditional_expression_t *conditional = &result->conditional;
6797         conditional->base.source_position = *HERE;
6798         conditional->condition            = expression;
6799
6800         eat('?');
6801         add_anchor_token(':');
6802
6803         /* 6.5.15.2 */
6804         type_t *const condition_type_orig = expression->base.type;
6805         type_t *const condition_type      = skip_typeref(condition_type_orig);
6806         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
6807                 type_error("expected a scalar type in conditional condition",
6808                            &expression->base.source_position, condition_type_orig);
6809         }
6810
6811         expression_t *true_expression = parse_expression();
6812         rem_anchor_token(':');
6813         expect(':');
6814         expression_t *false_expression = parse_sub_expression(precedence);
6815
6816         type_t *const orig_true_type  = true_expression->base.type;
6817         type_t *const orig_false_type = false_expression->base.type;
6818         type_t *const true_type       = skip_typeref(orig_true_type);
6819         type_t *const false_type      = skip_typeref(orig_false_type);
6820
6821         /* 6.5.15.3 */
6822         type_t *result_type;
6823         if (is_type_atomic(true_type, ATOMIC_TYPE_VOID) ||
6824                 is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
6825                 if (!is_type_atomic(true_type, ATOMIC_TYPE_VOID)
6826                     || !is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
6827                         warningf(&conditional->base.source_position,
6828                                         "ISO C forbids conditional expression with only one void side");
6829                 }
6830                 result_type = type_void;
6831         } else if (is_type_arithmetic(true_type)
6832                    && is_type_arithmetic(false_type)) {
6833                 result_type = semantic_arithmetic(true_type, false_type);
6834
6835                 true_expression  = create_implicit_cast(true_expression, result_type);
6836                 false_expression = create_implicit_cast(false_expression, result_type);
6837
6838                 conditional->true_expression  = true_expression;
6839                 conditional->false_expression = false_expression;
6840                 conditional->base.type        = result_type;
6841         } else if (same_compound_type(true_type, false_type)) {
6842                 /* just take 1 of the 2 types */
6843                 result_type = true_type;
6844         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
6845                 type_t *pointer_type;
6846                 type_t *other_type;
6847                 expression_t *other_expression;
6848                 if (is_type_pointer(true_type) &&
6849                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
6850                         pointer_type     = true_type;
6851                         other_type       = false_type;
6852                         other_expression = false_expression;
6853                 } else {
6854                         pointer_type     = false_type;
6855                         other_type       = true_type;
6856                         other_expression = true_expression;
6857                 }
6858
6859                 if (is_null_pointer_constant(other_expression)) {
6860                         result_type = pointer_type;
6861                 } else if (is_type_pointer(other_type)) {
6862                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
6863                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
6864
6865                         type_t *to;
6866                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
6867                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
6868                                 to = type_void;
6869                         } else if (types_compatible(get_unqualified_type(to1),
6870                                                     get_unqualified_type(to2))) {
6871                                 to = to1;
6872                         } else {
6873                                 warningf(&conditional->base.source_position,
6874                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
6875                                         true_type, false_type);
6876                                 to = type_void;
6877                         }
6878
6879                         type_t *const copy = duplicate_type(to);
6880                         copy->base.qualifiers = to1->base.qualifiers | to2->base.qualifiers;
6881
6882                         type_t *const type = typehash_insert(copy);
6883                         if (type != copy)
6884                                 free_type(copy);
6885
6886                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
6887                 } else if (is_type_integer(other_type)) {
6888                         warningf(&conditional->base.source_position,
6889                                         "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
6890                         result_type = pointer_type;
6891                 } else {
6892                         type_error_incompatible("while parsing conditional",
6893                                         &expression->base.source_position, true_type, false_type);
6894                         result_type = type_error_type;
6895                 }
6896         } else {
6897                 /* TODO: one pointer to void*, other some pointer */
6898
6899                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
6900                         type_error_incompatible("while parsing conditional",
6901                                                 &conditional->base.source_position, true_type,
6902                                                 false_type);
6903                 }
6904                 result_type = type_error_type;
6905         }
6906
6907         conditional->true_expression
6908                 = create_implicit_cast(true_expression, result_type);
6909         conditional->false_expression
6910                 = create_implicit_cast(false_expression, result_type);
6911         conditional->base.type = result_type;
6912         return result;
6913 end_error:
6914         return create_invalid_expression();
6915 }
6916
6917 /**
6918  * Parse an extension expression.
6919  */
6920 static expression_t *parse_extension(unsigned precedence)
6921 {
6922         eat(T___extension__);
6923
6924         /* TODO enable extensions */
6925         expression_t *expression = parse_sub_expression(precedence);
6926         /* TODO disable extensions */
6927         return expression;
6928 }
6929
6930 /**
6931  * Parse a __builtin_classify_type() expression.
6932  */
6933 static expression_t *parse_builtin_classify_type(const unsigned precedence)
6934 {
6935         eat(T___builtin_classify_type);
6936
6937         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
6938         result->base.type    = type_int;
6939
6940         expect('(');
6941         add_anchor_token(')');
6942         expression_t *expression = parse_sub_expression(precedence);
6943         rem_anchor_token(')');
6944         expect(')');
6945         result->classify_type.type_expression = expression;
6946
6947         return result;
6948 end_error:
6949         return create_invalid_expression();
6950 }
6951
6952 static bool check_pointer_arithmetic(const source_position_t *source_position,
6953                                      type_t *pointer_type,
6954                                      type_t *orig_pointer_type)
6955 {
6956         type_t *points_to = pointer_type->pointer.points_to;
6957         points_to = skip_typeref(points_to);
6958
6959         if (is_type_incomplete(points_to) &&
6960                         (! (c_mode & _GNUC)
6961                          || !is_type_atomic(points_to, ATOMIC_TYPE_VOID))) {
6962                 errorf(source_position,
6963                            "arithmetic with pointer to incomplete type '%T' not allowed",
6964                            orig_pointer_type);
6965                 return false;
6966         } else if (is_type_function(points_to)) {
6967                 errorf(source_position,
6968                            "arithmetic with pointer to function type '%T' not allowed",
6969                            orig_pointer_type);
6970                 return false;
6971         }
6972         return true;
6973 }
6974
6975 static void semantic_incdec(unary_expression_t *expression)
6976 {
6977         type_t *const orig_type = expression->value->base.type;
6978         type_t *const type      = skip_typeref(orig_type);
6979         if (is_type_pointer(type)) {
6980                 if (!check_pointer_arithmetic(&expression->base.source_position,
6981                                               type, orig_type)) {
6982                         return;
6983                 }
6984         } else if (!is_type_real(type) && is_type_valid(type)) {
6985                 /* TODO: improve error message */
6986                 errorf(&expression->base.source_position,
6987                        "operation needs an arithmetic or pointer type");
6988                 return;
6989         }
6990         expression->base.type = orig_type;
6991 }
6992
6993 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
6994 {
6995         type_t *const orig_type = expression->value->base.type;
6996         type_t *const type      = skip_typeref(orig_type);
6997         if (!is_type_arithmetic(type)) {
6998                 if (is_type_valid(type)) {
6999                         /* TODO: improve error message */
7000                         errorf(&expression->base.source_position,
7001                                "operation needs an arithmetic type");
7002                 }
7003                 return;
7004         }
7005
7006         expression->base.type = orig_type;
7007 }
7008
7009 static void semantic_not(unary_expression_t *expression)
7010 {
7011         type_t *const orig_type = expression->value->base.type;
7012         type_t *const type      = skip_typeref(orig_type);
7013         if (!is_type_scalar(type) && is_type_valid(type)) {
7014                 errorf(&expression->base.source_position,
7015                        "operand of ! must be of scalar type");
7016         }
7017
7018         expression->base.type = type_int;
7019 }
7020
7021 static void semantic_unexpr_integer(unary_expression_t *expression)
7022 {
7023         type_t *const orig_type = expression->value->base.type;
7024         type_t *const type      = skip_typeref(orig_type);
7025         if (!is_type_integer(type)) {
7026                 if (is_type_valid(type)) {
7027                         errorf(&expression->base.source_position,
7028                                "operand of ~ must be of integer type");
7029                 }
7030                 return;
7031         }
7032
7033         expression->base.type = orig_type;
7034 }
7035
7036 static void semantic_dereference(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_pointer(type)) {
7041                 if (is_type_valid(type)) {
7042                         errorf(&expression->base.source_position,
7043                                "Unary '*' needs pointer or arrray type, but type '%T' given", orig_type);
7044                 }
7045                 return;
7046         }
7047
7048         type_t *result_type   = type->pointer.points_to;
7049         result_type           = automatic_type_conversion(result_type);
7050         expression->base.type = result_type;
7051 }
7052
7053 static void set_address_taken(expression_t *expression, bool may_be_register)
7054 {
7055         if (expression->kind != EXPR_REFERENCE)
7056                 return;
7057
7058         declaration_t *const declaration = expression->reference.declaration;
7059         /* happens for parse errors */
7060         if (declaration == NULL)
7061                 return;
7062
7063         if (declaration->storage_class == STORAGE_CLASS_REGISTER && !may_be_register) {
7064                 errorf(&expression->base.source_position,
7065                                 "address of register variable '%Y' requested",
7066                                 declaration->symbol);
7067         } else {
7068                 declaration->address_taken = 1;
7069         }
7070 }
7071
7072 /**
7073  * Check the semantic of the address taken expression.
7074  */
7075 static void semantic_take_addr(unary_expression_t *expression)
7076 {
7077         expression_t *value = expression->value;
7078         value->base.type    = revert_automatic_type_conversion(value);
7079
7080         type_t *orig_type = value->base.type;
7081         if (!is_type_valid(orig_type))
7082                 return;
7083
7084         set_address_taken(value, false);
7085
7086         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
7087 }
7088
7089 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc)   \
7090 static expression_t *parse_##unexpression_type(unsigned precedence)            \
7091 {                                                                              \
7092         expression_t *unary_expression                                             \
7093                 = allocate_expression_zero(unexpression_type);                         \
7094         unary_expression->base.source_position = *HERE;                            \
7095         eat(token_type);                                                           \
7096         unary_expression->unary.value = parse_sub_expression(precedence);          \
7097                                                                                    \
7098         sfunc(&unary_expression->unary);                                           \
7099                                                                                    \
7100         return unary_expression;                                                   \
7101 }
7102
7103 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
7104                                semantic_unexpr_arithmetic)
7105 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
7106                                semantic_unexpr_arithmetic)
7107 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
7108                                semantic_not)
7109 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
7110                                semantic_dereference)
7111 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
7112                                semantic_take_addr)
7113 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
7114                                semantic_unexpr_integer)
7115 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
7116                                semantic_incdec)
7117 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
7118                                semantic_incdec)
7119
7120 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
7121                                                sfunc)                         \
7122 static expression_t *parse_##unexpression_type(unsigned precedence,           \
7123                                                expression_t *left)            \
7124 {                                                                             \
7125         (void) precedence;                                                        \
7126                                                                               \
7127         expression_t *unary_expression                                            \
7128                 = allocate_expression_zero(unexpression_type);                        \
7129         unary_expression->base.source_position = *HERE;                           \
7130         eat(token_type);                                                          \
7131         unary_expression->unary.value          = left;                            \
7132                                                                                   \
7133         sfunc(&unary_expression->unary);                                          \
7134                                                                               \
7135         return unary_expression;                                                  \
7136 }
7137
7138 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
7139                                        EXPR_UNARY_POSTFIX_INCREMENT,
7140                                        semantic_incdec)
7141 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
7142                                        EXPR_UNARY_POSTFIX_DECREMENT,
7143                                        semantic_incdec)
7144
7145 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
7146 {
7147         /* TODO: handle complex + imaginary types */
7148
7149         /* § 6.3.1.8 Usual arithmetic conversions */
7150         if (type_left == type_long_double || type_right == type_long_double) {
7151                 return type_long_double;
7152         } else if (type_left == type_double || type_right == type_double) {
7153                 return type_double;
7154         } else if (type_left == type_float || type_right == type_float) {
7155                 return type_float;
7156         }
7157
7158         type_left  = promote_integer(type_left);
7159         type_right = promote_integer(type_right);
7160
7161         if (type_left == type_right)
7162                 return type_left;
7163
7164         bool const signed_left  = is_type_signed(type_left);
7165         bool const signed_right = is_type_signed(type_right);
7166         int  const rank_left    = get_rank(type_left);
7167         int  const rank_right   = get_rank(type_right);
7168
7169         if (signed_left == signed_right)
7170                 return rank_left >= rank_right ? type_left : type_right;
7171
7172         int     s_rank;
7173         int     u_rank;
7174         type_t *s_type;
7175         type_t *u_type;
7176         if (signed_left) {
7177                 s_rank = rank_left;
7178                 s_type = type_left;
7179                 u_rank = rank_right;
7180                 u_type = type_right;
7181         } else {
7182                 s_rank = rank_right;
7183                 s_type = type_right;
7184                 u_rank = rank_left;
7185                 u_type = type_left;
7186         }
7187
7188         if (u_rank >= s_rank)
7189                 return u_type;
7190
7191         if (get_atomic_type_size(s_rank) > get_atomic_type_size(u_rank))
7192                 return s_type;
7193
7194         switch (s_rank) {
7195                 case ATOMIC_TYPE_INT:      return type_int;
7196                 case ATOMIC_TYPE_LONG:     return type_long;
7197                 case ATOMIC_TYPE_LONGLONG: return type_long_long;
7198
7199                 default: panic("invalid atomic type");
7200         }
7201 }
7202
7203 /**
7204  * Check the semantic restrictions for a binary expression.
7205  */
7206 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
7207 {
7208         expression_t *const left            = expression->left;
7209         expression_t *const right           = expression->right;
7210         type_t       *const orig_type_left  = left->base.type;
7211         type_t       *const orig_type_right = right->base.type;
7212         type_t       *const type_left       = skip_typeref(orig_type_left);
7213         type_t       *const type_right      = skip_typeref(orig_type_right);
7214
7215         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7216                 /* TODO: improve error message */
7217                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7218                         errorf(&expression->base.source_position,
7219                                "operation needs arithmetic types");
7220                 }
7221                 return;
7222         }
7223
7224         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7225         expression->left      = create_implicit_cast(left, arithmetic_type);
7226         expression->right     = create_implicit_cast(right, arithmetic_type);
7227         expression->base.type = arithmetic_type;
7228 }
7229
7230 static void semantic_shift_op(binary_expression_t *expression)
7231 {
7232         expression_t *const left            = expression->left;
7233         expression_t *const right           = expression->right;
7234         type_t       *const orig_type_left  = left->base.type;
7235         type_t       *const orig_type_right = right->base.type;
7236         type_t       *      type_left       = skip_typeref(orig_type_left);
7237         type_t       *      type_right      = skip_typeref(orig_type_right);
7238
7239         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
7240                 /* TODO: improve error message */
7241                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7242                         errorf(&expression->base.source_position,
7243                                "operands of shift operation must have integer types");
7244                 }
7245                 return;
7246         }
7247
7248         type_left  = promote_integer(type_left);
7249         type_right = promote_integer(type_right);
7250
7251         expression->left      = create_implicit_cast(left, type_left);
7252         expression->right     = create_implicit_cast(right, type_right);
7253         expression->base.type = type_left;
7254 }
7255
7256 static void semantic_add(binary_expression_t *expression)
7257 {
7258         expression_t *const left            = expression->left;
7259         expression_t *const right           = expression->right;
7260         type_t       *const orig_type_left  = left->base.type;
7261         type_t       *const orig_type_right = right->base.type;
7262         type_t       *const type_left       = skip_typeref(orig_type_left);
7263         type_t       *const type_right      = skip_typeref(orig_type_right);
7264
7265         /* § 6.5.6 */
7266         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
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                 return;
7272         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7273                 check_pointer_arithmetic(&expression->base.source_position,
7274                                          type_left, orig_type_left);
7275                 expression->base.type = type_left;
7276         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
7277                 check_pointer_arithmetic(&expression->base.source_position,
7278                                          type_right, orig_type_right);
7279                 expression->base.type = type_right;
7280         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7281                 errorf(&expression->base.source_position,
7282                        "invalid operands to binary + ('%T', '%T')",
7283                        orig_type_left, orig_type_right);
7284         }
7285 }
7286
7287 static void semantic_sub(binary_expression_t *expression)
7288 {
7289         expression_t            *const left            = expression->left;
7290         expression_t            *const right           = expression->right;
7291         type_t                  *const orig_type_left  = left->base.type;
7292         type_t                  *const orig_type_right = right->base.type;
7293         type_t                  *const type_left       = skip_typeref(orig_type_left);
7294         type_t                  *const type_right      = skip_typeref(orig_type_right);
7295         source_position_t const *const pos             = &expression->base.source_position;
7296
7297         /* § 5.6.5 */
7298         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7299                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7300                 expression->left        = create_implicit_cast(left, arithmetic_type);
7301                 expression->right       = create_implicit_cast(right, arithmetic_type);
7302                 expression->base.type =  arithmetic_type;
7303                 return;
7304         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7305                 check_pointer_arithmetic(&expression->base.source_position,
7306                                          type_left, orig_type_left);
7307                 expression->base.type = type_left;
7308         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7309                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
7310                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
7311                 if (!types_compatible(unqual_left, unqual_right)) {
7312                         errorf(pos,
7313                                "subtracting pointers to incompatible types '%T' and '%T'",
7314                                orig_type_left, orig_type_right);
7315                 } else if (!is_type_object(unqual_left)) {
7316                         if (is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
7317                                 warningf(pos, "subtracting pointers to void");
7318                         } else {
7319                                 errorf(pos, "subtracting pointers to non-object types '%T'",
7320                                        orig_type_left);
7321                         }
7322                 }
7323                 expression->base.type = type_ptrdiff_t;
7324         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7325                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
7326                        orig_type_left, orig_type_right);
7327         }
7328 }
7329
7330 /**
7331  * Check the semantics of comparison expressions.
7332  *
7333  * @param expression   The expression to check.
7334  */
7335 static void semantic_comparison(binary_expression_t *expression)
7336 {
7337         expression_t *left            = expression->left;
7338         expression_t *right           = expression->right;
7339         type_t       *orig_type_left  = left->base.type;
7340         type_t       *orig_type_right = right->base.type;
7341
7342         type_t *type_left  = skip_typeref(orig_type_left);
7343         type_t *type_right = skip_typeref(orig_type_right);
7344
7345         /* TODO non-arithmetic types */
7346         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7347                 /* test for signed vs unsigned compares */
7348                 if (warning.sign_compare &&
7349                     (expression->base.kind != EXPR_BINARY_EQUAL &&
7350                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
7351                     (is_type_signed(type_left) != is_type_signed(type_right))) {
7352
7353                         /* check if 1 of the operands is a constant, in this case we just
7354                          * check wether we can safely represent the resulting constant in
7355                          * the type of the other operand. */
7356                         expression_t *const_expr = NULL;
7357                         expression_t *other_expr = NULL;
7358
7359                         if (is_constant_expression(left)) {
7360                                 const_expr = left;
7361                                 other_expr = right;
7362                         } else if (is_constant_expression(right)) {
7363                                 const_expr = right;
7364                                 other_expr = left;
7365                         }
7366
7367                         if (const_expr != NULL) {
7368                                 type_t *other_type = skip_typeref(other_expr->base.type);
7369                                 long    val        = fold_constant(const_expr);
7370                                 /* TODO: check if val can be represented by other_type */
7371                                 (void) other_type;
7372                                 (void) val;
7373                         }
7374                         warningf(&expression->base.source_position,
7375                                  "comparison between signed and unsigned");
7376                 }
7377                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7378                 expression->left        = create_implicit_cast(left, arithmetic_type);
7379                 expression->right       = create_implicit_cast(right, arithmetic_type);
7380                 expression->base.type   = arithmetic_type;
7381                 if (warning.float_equal &&
7382                     (expression->base.kind == EXPR_BINARY_EQUAL ||
7383                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
7384                     is_type_float(arithmetic_type)) {
7385                         warningf(&expression->base.source_position,
7386                                  "comparing floating point with == or != is unsafe");
7387                 }
7388         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7389                 /* TODO check compatibility */
7390         } else if (is_type_pointer(type_left)) {
7391                 expression->right = create_implicit_cast(right, type_left);
7392         } else if (is_type_pointer(type_right)) {
7393                 expression->left = create_implicit_cast(left, type_right);
7394         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7395                 type_error_incompatible("invalid operands in comparison",
7396                                         &expression->base.source_position,
7397                                         type_left, type_right);
7398         }
7399         expression->base.type = type_int;
7400 }
7401
7402 /**
7403  * Checks if a compound type has constant fields.
7404  */
7405 static bool has_const_fields(const compound_type_t *type)
7406 {
7407         const scope_t       *scope       = &type->declaration->scope;
7408         const declaration_t *declaration = scope->declarations;
7409
7410         for (; declaration != NULL; declaration = declaration->next) {
7411                 if (declaration->namespc != NAMESPACE_NORMAL)
7412                         continue;
7413
7414                 const type_t *decl_type = skip_typeref(declaration->type);
7415                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
7416                         return true;
7417         }
7418         /* TODO */
7419         return false;
7420 }
7421
7422 static bool is_lvalue(const expression_t *expression)
7423 {
7424         switch (expression->kind) {
7425         case EXPR_REFERENCE:
7426         case EXPR_ARRAY_ACCESS:
7427         case EXPR_SELECT:
7428         case EXPR_UNARY_DEREFERENCE:
7429                 return true;
7430
7431         default:
7432                 return false;
7433         }
7434 }
7435
7436 static bool is_valid_assignment_lhs(expression_t const* const left)
7437 {
7438         type_t *const orig_type_left = revert_automatic_type_conversion(left);
7439         type_t *const type_left      = skip_typeref(orig_type_left);
7440
7441         if (!is_lvalue(left)) {
7442                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
7443                        left);
7444                 return false;
7445         }
7446
7447         if (is_type_array(type_left)) {
7448                 errorf(HERE, "cannot assign to arrays ('%E')", left);
7449                 return false;
7450         }
7451         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
7452                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
7453                        orig_type_left);
7454                 return false;
7455         }
7456         if (is_type_incomplete(type_left)) {
7457                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
7458                        left, orig_type_left);
7459                 return false;
7460         }
7461         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
7462                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
7463                        left, orig_type_left);
7464                 return false;
7465         }
7466
7467         return true;
7468 }
7469
7470 static void semantic_arithmetic_assign(binary_expression_t *expression)
7471 {
7472         expression_t *left            = expression->left;
7473         expression_t *right           = expression->right;
7474         type_t       *orig_type_left  = left->base.type;
7475         type_t       *orig_type_right = right->base.type;
7476
7477         if (!is_valid_assignment_lhs(left))
7478                 return;
7479
7480         type_t *type_left  = skip_typeref(orig_type_left);
7481         type_t *type_right = skip_typeref(orig_type_right);
7482
7483         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7484                 /* TODO: improve error message */
7485                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7486                         errorf(&expression->base.source_position,
7487                                "operation needs arithmetic types");
7488                 }
7489                 return;
7490         }
7491
7492         /* combined instructions are tricky. We can't create an implicit cast on
7493          * the left side, because we need the uncasted form for the store.
7494          * The ast2firm pass has to know that left_type must be right_type
7495          * for the arithmetic operation and create a cast by itself */
7496         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7497         expression->right       = create_implicit_cast(right, arithmetic_type);
7498         expression->base.type   = type_left;
7499 }
7500
7501 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
7502 {
7503         expression_t *const left            = expression->left;
7504         expression_t *const right           = expression->right;
7505         type_t       *const orig_type_left  = left->base.type;
7506         type_t       *const orig_type_right = right->base.type;
7507         type_t       *const type_left       = skip_typeref(orig_type_left);
7508         type_t       *const type_right      = skip_typeref(orig_type_right);
7509
7510         if (!is_valid_assignment_lhs(left))
7511                 return;
7512
7513         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7514                 /* combined instructions are tricky. We can't create an implicit cast on
7515                  * the left side, because we need the uncasted form for the store.
7516                  * The ast2firm pass has to know that left_type must be right_type
7517                  * for the arithmetic operation and create a cast by itself */
7518                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
7519                 expression->right     = create_implicit_cast(right, arithmetic_type);
7520                 expression->base.type = type_left;
7521         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7522                 check_pointer_arithmetic(&expression->base.source_position,
7523                                          type_left, orig_type_left);
7524                 expression->base.type = type_left;
7525         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7526                 errorf(&expression->base.source_position,
7527                        "incompatible types '%T' and '%T' in assignment",
7528                        orig_type_left, orig_type_right);
7529         }
7530 }
7531
7532 /**
7533  * Check the semantic restrictions of a logical expression.
7534  */
7535 static void semantic_logical_op(binary_expression_t *expression)
7536 {
7537         expression_t *const left            = expression->left;
7538         expression_t *const right           = expression->right;
7539         type_t       *const orig_type_left  = left->base.type;
7540         type_t       *const orig_type_right = right->base.type;
7541         type_t       *const type_left       = skip_typeref(orig_type_left);
7542         type_t       *const type_right      = skip_typeref(orig_type_right);
7543
7544         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
7545                 /* TODO: improve error message */
7546                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7547                         errorf(&expression->base.source_position,
7548                                "operation needs scalar types");
7549                 }
7550                 return;
7551         }
7552
7553         expression->base.type = type_int;
7554 }
7555
7556 /**
7557  * Check the semantic restrictions of a binary assign expression.
7558  */
7559 static void semantic_binexpr_assign(binary_expression_t *expression)
7560 {
7561         expression_t *left           = expression->left;
7562         type_t       *orig_type_left = left->base.type;
7563
7564         type_t *type_left = revert_automatic_type_conversion(left);
7565         type_left         = skip_typeref(orig_type_left);
7566
7567         if (!is_valid_assignment_lhs(left))
7568                 return;
7569
7570         assign_error_t error = semantic_assign(orig_type_left, expression->right);
7571         report_assign_error(error, orig_type_left, expression->right,
7572                         "assignment", &left->base.source_position);
7573         expression->right = create_implicit_cast(expression->right, orig_type_left);
7574         expression->base.type = orig_type_left;
7575 }
7576
7577 /**
7578  * Determine if the outermost operation (or parts thereof) of the given
7579  * expression has no effect in order to generate a warning about this fact.
7580  * Therefore in some cases this only examines some of the operands of the
7581  * expression (see comments in the function and examples below).
7582  * Examples:
7583  *   f() + 23;    // warning, because + has no effect
7584  *   x || f();    // no warning, because x controls execution of f()
7585  *   x ? y : f(); // warning, because y has no effect
7586  *   (void)x;     // no warning to be able to suppress the warning
7587  * This function can NOT be used for an "expression has definitely no effect"-
7588  * analysis. */
7589 static bool expression_has_effect(const expression_t *const expr)
7590 {
7591         switch (expr->kind) {
7592                 case EXPR_UNKNOWN:                   break;
7593                 case EXPR_INVALID:                   return true; /* do NOT warn */
7594                 case EXPR_REFERENCE:                 return false;
7595                 /* suppress the warning for microsoft __noop operations */
7596                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
7597                 case EXPR_CHARACTER_CONSTANT:        return false;
7598                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
7599                 case EXPR_STRING_LITERAL:            return false;
7600                 case EXPR_WIDE_STRING_LITERAL:       return false;
7601
7602                 case EXPR_CALL: {
7603                         const call_expression_t *const call = &expr->call;
7604                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
7605                                 return true;
7606
7607                         switch (call->function->builtin_symbol.symbol->ID) {
7608                                 case T___builtin_va_end: return true;
7609                                 default:                 return false;
7610                         }
7611                 }
7612
7613                 /* Generate the warning if either the left or right hand side of a
7614                  * conditional expression has no effect */
7615                 case EXPR_CONDITIONAL: {
7616                         const conditional_expression_t *const cond = &expr->conditional;
7617                         return
7618                                 expression_has_effect(cond->true_expression) &&
7619                                 expression_has_effect(cond->false_expression);
7620                 }
7621
7622                 case EXPR_SELECT:                    return false;
7623                 case EXPR_ARRAY_ACCESS:              return false;
7624                 case EXPR_SIZEOF:                    return false;
7625                 case EXPR_CLASSIFY_TYPE:             return false;
7626                 case EXPR_ALIGNOF:                   return false;
7627
7628                 case EXPR_FUNCNAME:                  return false;
7629                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
7630                 case EXPR_BUILTIN_CONSTANT_P:        return false;
7631                 case EXPR_BUILTIN_PREFETCH:          return true;
7632                 case EXPR_OFFSETOF:                  return false;
7633                 case EXPR_VA_START:                  return true;
7634                 case EXPR_VA_ARG:                    return true;
7635                 case EXPR_STATEMENT:                 return true; // TODO
7636                 case EXPR_COMPOUND_LITERAL:          return false;
7637
7638                 case EXPR_UNARY_NEGATE:              return false;
7639                 case EXPR_UNARY_PLUS:                return false;
7640                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
7641                 case EXPR_UNARY_NOT:                 return false;
7642                 case EXPR_UNARY_DEREFERENCE:         return false;
7643                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
7644                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
7645                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
7646                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
7647                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
7648
7649                 /* Treat void casts as if they have an effect in order to being able to
7650                  * suppress the warning */
7651                 case EXPR_UNARY_CAST: {
7652                         type_t *const type = skip_typeref(expr->base.type);
7653                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
7654                 }
7655
7656                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
7657                 case EXPR_UNARY_ASSUME:              return true;
7658
7659                 case EXPR_BINARY_ADD:                return false;
7660                 case EXPR_BINARY_SUB:                return false;
7661                 case EXPR_BINARY_MUL:                return false;
7662                 case EXPR_BINARY_DIV:                return false;
7663                 case EXPR_BINARY_MOD:                return false;
7664                 case EXPR_BINARY_EQUAL:              return false;
7665                 case EXPR_BINARY_NOTEQUAL:           return false;
7666                 case EXPR_BINARY_LESS:               return false;
7667                 case EXPR_BINARY_LESSEQUAL:          return false;
7668                 case EXPR_BINARY_GREATER:            return false;
7669                 case EXPR_BINARY_GREATEREQUAL:       return false;
7670                 case EXPR_BINARY_BITWISE_AND:        return false;
7671                 case EXPR_BINARY_BITWISE_OR:         return false;
7672                 case EXPR_BINARY_BITWISE_XOR:        return false;
7673                 case EXPR_BINARY_SHIFTLEFT:          return false;
7674                 case EXPR_BINARY_SHIFTRIGHT:         return false;
7675                 case EXPR_BINARY_ASSIGN:             return true;
7676                 case EXPR_BINARY_MUL_ASSIGN:         return true;
7677                 case EXPR_BINARY_DIV_ASSIGN:         return true;
7678                 case EXPR_BINARY_MOD_ASSIGN:         return true;
7679                 case EXPR_BINARY_ADD_ASSIGN:         return true;
7680                 case EXPR_BINARY_SUB_ASSIGN:         return true;
7681                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
7682                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
7683                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
7684                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
7685                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
7686
7687                 /* Only examine the right hand side of && and ||, because the left hand
7688                  * side already has the effect of controlling the execution of the right
7689                  * hand side */
7690                 case EXPR_BINARY_LOGICAL_AND:
7691                 case EXPR_BINARY_LOGICAL_OR:
7692                 /* Only examine the right hand side of a comma expression, because the left
7693                  * hand side has a separate warning */
7694                 case EXPR_BINARY_COMMA:
7695                         return expression_has_effect(expr->binary.right);
7696
7697                 case EXPR_BINARY_BUILTIN_EXPECT:     return true;
7698                 case EXPR_BINARY_ISGREATER:          return false;
7699                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
7700                 case EXPR_BINARY_ISLESS:             return false;
7701                 case EXPR_BINARY_ISLESSEQUAL:        return false;
7702                 case EXPR_BINARY_ISLESSGREATER:      return false;
7703                 case EXPR_BINARY_ISUNORDERED:        return false;
7704         }
7705
7706         internal_errorf(HERE, "unexpected expression");
7707 }
7708
7709 static void semantic_comma(binary_expression_t *expression)
7710 {
7711         if (warning.unused_value) {
7712                 const expression_t *const left = expression->left;
7713                 if (!expression_has_effect(left)) {
7714                         warningf(&left->base.source_position,
7715                                  "left-hand operand of comma expression has no effect");
7716                 }
7717         }
7718         expression->base.type = expression->right->base.type;
7719 }
7720
7721 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr)  \
7722 static expression_t *parse_##binexpression_type(unsigned precedence,      \
7723                                                 expression_t *left)       \
7724 {                                                                         \
7725         expression_t *binexpr = allocate_expression_zero(binexpression_type); \
7726         binexpr->base.source_position = *HERE;                                \
7727         binexpr->binary.left          = left;                                 \
7728         eat(token_type);                                                      \
7729                                                                           \
7730         expression_t *right = parse_sub_expression(precedence + lr);          \
7731                                                                           \
7732         binexpr->binary.right = right;                                        \
7733         sfunc(&binexpr->binary);                                              \
7734                                                                           \
7735         return binexpr;                                                       \
7736 }
7737
7738 CREATE_BINEXPR_PARSER(',', EXPR_BINARY_COMMA,    semantic_comma, 1)
7739 CREATE_BINEXPR_PARSER('*', EXPR_BINARY_MUL,      semantic_binexpr_arithmetic, 1)
7740 CREATE_BINEXPR_PARSER('/', EXPR_BINARY_DIV,      semantic_binexpr_arithmetic, 1)
7741 CREATE_BINEXPR_PARSER('%', EXPR_BINARY_MOD,      semantic_binexpr_arithmetic, 1)
7742 CREATE_BINEXPR_PARSER('+', EXPR_BINARY_ADD,      semantic_add, 1)
7743 CREATE_BINEXPR_PARSER('-', EXPR_BINARY_SUB,      semantic_sub, 1)
7744 CREATE_BINEXPR_PARSER('<', EXPR_BINARY_LESS,     semantic_comparison, 1)
7745 CREATE_BINEXPR_PARSER('>', EXPR_BINARY_GREATER,  semantic_comparison, 1)
7746 CREATE_BINEXPR_PARSER('=', EXPR_BINARY_ASSIGN,   semantic_binexpr_assign, 0)
7747
7748 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,
7749                       semantic_comparison, 1)
7750 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,
7751                       semantic_comparison, 1)
7752 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,
7753                       semantic_comparison, 1)
7754 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,
7755                       semantic_comparison, 1)
7756
7757 CREATE_BINEXPR_PARSER('&', EXPR_BINARY_BITWISE_AND,
7758                       semantic_binexpr_arithmetic, 1)
7759 CREATE_BINEXPR_PARSER('|', EXPR_BINARY_BITWISE_OR,
7760                       semantic_binexpr_arithmetic, 1)
7761 CREATE_BINEXPR_PARSER('^', EXPR_BINARY_BITWISE_XOR,
7762                       semantic_binexpr_arithmetic, 1)
7763 CREATE_BINEXPR_PARSER(T_ANDAND, EXPR_BINARY_LOGICAL_AND,
7764                       semantic_logical_op, 1)
7765 CREATE_BINEXPR_PARSER(T_PIPEPIPE, EXPR_BINARY_LOGICAL_OR,
7766                       semantic_logical_op, 1)
7767 CREATE_BINEXPR_PARSER(T_LESSLESS, EXPR_BINARY_SHIFTLEFT,
7768                       semantic_shift_op, 1)
7769 CREATE_BINEXPR_PARSER(T_GREATERGREATER, EXPR_BINARY_SHIFTRIGHT,
7770                       semantic_shift_op, 1)
7771 CREATE_BINEXPR_PARSER(T_PLUSEQUAL, EXPR_BINARY_ADD_ASSIGN,
7772                       semantic_arithmetic_addsubb_assign, 0)
7773 CREATE_BINEXPR_PARSER(T_MINUSEQUAL, EXPR_BINARY_SUB_ASSIGN,
7774                       semantic_arithmetic_addsubb_assign, 0)
7775 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, EXPR_BINARY_MUL_ASSIGN,
7776                       semantic_arithmetic_assign, 0)
7777 CREATE_BINEXPR_PARSER(T_SLASHEQUAL, EXPR_BINARY_DIV_ASSIGN,
7778                       semantic_arithmetic_assign, 0)
7779 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, EXPR_BINARY_MOD_ASSIGN,
7780                       semantic_arithmetic_assign, 0)
7781 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, EXPR_BINARY_SHIFTLEFT_ASSIGN,
7782                       semantic_arithmetic_assign, 0)
7783 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, EXPR_BINARY_SHIFTRIGHT_ASSIGN,
7784                       semantic_arithmetic_assign, 0)
7785 CREATE_BINEXPR_PARSER(T_ANDEQUAL, EXPR_BINARY_BITWISE_AND_ASSIGN,
7786                       semantic_arithmetic_assign, 0)
7787 CREATE_BINEXPR_PARSER(T_PIPEEQUAL, EXPR_BINARY_BITWISE_OR_ASSIGN,
7788                       semantic_arithmetic_assign, 0)
7789 CREATE_BINEXPR_PARSER(T_CARETEQUAL, EXPR_BINARY_BITWISE_XOR_ASSIGN,
7790                       semantic_arithmetic_assign, 0)
7791
7792 static expression_t *parse_sub_expression(unsigned precedence)
7793 {
7794         if (token.type < 0) {
7795                 return expected_expression_error();
7796         }
7797
7798         expression_parser_function_t *parser
7799                 = &expression_parsers[token.type];
7800         source_position_t             source_position = token.source_position;
7801         expression_t                 *left;
7802
7803         if (parser->parser != NULL) {
7804                 left = parser->parser(parser->precedence);
7805         } else {
7806                 left = parse_primary_expression();
7807         }
7808         assert(left != NULL);
7809         left->base.source_position = source_position;
7810
7811         while(true) {
7812                 if (token.type < 0) {
7813                         return expected_expression_error();
7814                 }
7815
7816                 parser = &expression_parsers[token.type];
7817                 if (parser->infix_parser == NULL)
7818                         break;
7819                 if (parser->infix_precedence < precedence)
7820                         break;
7821
7822                 left = parser->infix_parser(parser->infix_precedence, left);
7823
7824                 assert(left != NULL);
7825                 assert(left->kind != EXPR_UNKNOWN);
7826                 left->base.source_position = source_position;
7827         }
7828
7829         return left;
7830 }
7831
7832 /**
7833  * Parse an expression.
7834  */
7835 static expression_t *parse_expression(void)
7836 {
7837         return parse_sub_expression(1);
7838 }
7839
7840 /**
7841  * Register a parser for a prefix-like operator with given precedence.
7842  *
7843  * @param parser      the parser function
7844  * @param token_type  the token type of the prefix token
7845  * @param precedence  the precedence of the operator
7846  */
7847 static void register_expression_parser(parse_expression_function parser,
7848                                        int token_type, unsigned precedence)
7849 {
7850         expression_parser_function_t *entry = &expression_parsers[token_type];
7851
7852         if (entry->parser != NULL) {
7853                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
7854                 panic("trying to register multiple expression parsers for a token");
7855         }
7856         entry->parser     = parser;
7857         entry->precedence = precedence;
7858 }
7859
7860 /**
7861  * Register a parser for an infix operator with given precedence.
7862  *
7863  * @param parser      the parser function
7864  * @param token_type  the token type of the infix operator
7865  * @param precedence  the precedence of the operator
7866  */
7867 static void register_infix_parser(parse_expression_infix_function parser,
7868                 int token_type, unsigned precedence)
7869 {
7870         expression_parser_function_t *entry = &expression_parsers[token_type];
7871
7872         if (entry->infix_parser != NULL) {
7873                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
7874                 panic("trying to register multiple infix expression parsers for a "
7875                       "token");
7876         }
7877         entry->infix_parser     = parser;
7878         entry->infix_precedence = precedence;
7879 }
7880
7881 /**
7882  * Initialize the expression parsers.
7883  */
7884 static void init_expression_parsers(void)
7885 {
7886         memset(&expression_parsers, 0, sizeof(expression_parsers));
7887
7888         register_infix_parser(parse_array_expression,         '[',              30);
7889         register_infix_parser(parse_call_expression,          '(',              30);
7890         register_infix_parser(parse_select_expression,        '.',              30);
7891         register_infix_parser(parse_select_expression,        T_MINUSGREATER,   30);
7892         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,
7893                                                               T_PLUSPLUS,       30);
7894         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,
7895                                                               T_MINUSMINUS,     30);
7896
7897         register_infix_parser(parse_EXPR_BINARY_MUL,          '*',              17);
7898         register_infix_parser(parse_EXPR_BINARY_DIV,          '/',              17);
7899         register_infix_parser(parse_EXPR_BINARY_MOD,          '%',              17);
7900         register_infix_parser(parse_EXPR_BINARY_ADD,          '+',              16);
7901         register_infix_parser(parse_EXPR_BINARY_SUB,          '-',              16);
7902         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,    T_LESSLESS,       15);
7903         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,   T_GREATERGREATER, 15);
7904         register_infix_parser(parse_EXPR_BINARY_LESS,         '<',              14);
7905         register_infix_parser(parse_EXPR_BINARY_GREATER,      '>',              14);
7906         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,    T_LESSEQUAL,      14);
7907         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL, T_GREATEREQUAL,   14);
7908         register_infix_parser(parse_EXPR_BINARY_EQUAL,        T_EQUALEQUAL,     13);
7909         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,
7910                                                     T_EXCLAMATIONMARKEQUAL, 13);
7911         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,  '&',              12);
7912         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,  '^',              11);
7913         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,   '|',              10);
7914         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,  T_ANDAND,          9);
7915         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,   T_PIPEPIPE,        8);
7916         register_infix_parser(parse_conditional_expression,   '?',               7);
7917         register_infix_parser(parse_EXPR_BINARY_ASSIGN,       '=',               2);
7918         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,   T_PLUSEQUAL,       2);
7919         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,   T_MINUSEQUAL,      2);
7920         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,   T_ASTERISKEQUAL,   2);
7921         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,   T_SLASHEQUAL,      2);
7922         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,   T_PERCENTEQUAL,    2);
7923         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,
7924                                                                 T_LESSLESSEQUAL, 2);
7925         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,
7926                                                           T_GREATERGREATEREQUAL, 2);
7927         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN,
7928                                                                      T_ANDEQUAL, 2);
7929         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,
7930                                                                     T_PIPEEQUAL, 2);
7931         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN,
7932                                                                    T_CARETEQUAL, 2);
7933
7934         register_infix_parser(parse_EXPR_BINARY_COMMA,        ',',               1);
7935
7936         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-',      25);
7937         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+',      25);
7938         register_expression_parser(parse_EXPR_UNARY_NOT,              '!',      25);
7939         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~',      25);
7940         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*',      25);
7941         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&',      25);
7942         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT,
7943                                                                   T_PLUSPLUS,   25);
7944         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT,
7945                                                                   T_MINUSMINUS, 25);
7946         register_expression_parser(parse_sizeof,                      T_sizeof, 25);
7947         register_expression_parser(parse_alignof,                T___alignof__, 25);
7948         register_expression_parser(parse_extension,            T___extension__, 25);
7949         register_expression_parser(parse_builtin_classify_type,
7950                                                      T___builtin_classify_type, 25);
7951 }
7952
7953 /**
7954  * Parse a asm statement arguments specification.
7955  */
7956 static asm_argument_t *parse_asm_arguments(bool is_out)
7957 {
7958         asm_argument_t *result = NULL;
7959         asm_argument_t *last   = NULL;
7960
7961         while (token.type == T_STRING_LITERAL || token.type == '[') {
7962                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
7963                 memset(argument, 0, sizeof(argument[0]));
7964
7965                 if (token.type == '[') {
7966                         eat('[');
7967                         if (token.type != T_IDENTIFIER) {
7968                                 parse_error_expected("while parsing asm argument",
7969                                                      T_IDENTIFIER, NULL);
7970                                 return NULL;
7971                         }
7972                         argument->symbol = token.v.symbol;
7973
7974                         expect(']');
7975                 }
7976
7977                 argument->constraints = parse_string_literals();
7978                 expect('(');
7979                 add_anchor_token(')');
7980                 expression_t *expression = parse_expression();
7981                 rem_anchor_token(')');
7982                 if (is_out) {
7983                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
7984                          * change size or type representation (e.g. int -> long is ok, but
7985                          * int -> float is not) */
7986                         if (expression->kind == EXPR_UNARY_CAST) {
7987                                 type_t      *const type = expression->base.type;
7988                                 type_kind_t  const kind = type->kind;
7989                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
7990                                         unsigned flags;
7991                                         unsigned size;
7992                                         if (kind == TYPE_ATOMIC) {
7993                                                 atomic_type_kind_t const akind = type->atomic.akind;
7994                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
7995                                                 size  = get_atomic_type_size(akind);
7996                                         } else {
7997                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
7998                                                 size  = get_atomic_type_size(get_intptr_kind());
7999                                         }
8000
8001                                         do {
8002                                                 expression_t *const value      = expression->unary.value;
8003                                                 type_t       *const value_type = value->base.type;
8004                                                 type_kind_t   const value_kind = value_type->kind;
8005
8006                                                 unsigned value_flags;
8007                                                 unsigned value_size;
8008                                                 if (value_kind == TYPE_ATOMIC) {
8009                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
8010                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8011                                                         value_size  = get_atomic_type_size(value_akind);
8012                                                 } else if (value_kind == TYPE_POINTER) {
8013                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8014                                                         value_size  = get_atomic_type_size(get_intptr_kind());
8015                                                 } else {
8016                                                         break;
8017                                                 }
8018
8019                                                 if (value_flags != flags || value_size != size)
8020                                                         break;
8021
8022                                                 expression = value;
8023                                         } while (expression->kind == EXPR_UNARY_CAST);
8024                                 }
8025                         }
8026
8027                         if (!is_lvalue(expression)) {
8028                                 errorf(&expression->base.source_position,
8029                                        "asm output argument is not an lvalue");
8030                         }
8031                 }
8032                 argument->expression = expression;
8033                 expect(')');
8034
8035                 set_address_taken(expression, true);
8036
8037                 if (last != NULL) {
8038                         last->next = argument;
8039                 } else {
8040                         result = argument;
8041                 }
8042                 last = argument;
8043
8044                 if (token.type != ',')
8045                         break;
8046                 eat(',');
8047         }
8048
8049         return result;
8050 end_error:
8051         return NULL;
8052 }
8053
8054 /**
8055  * Parse a asm statement clobber specification.
8056  */
8057 static asm_clobber_t *parse_asm_clobbers(void)
8058 {
8059         asm_clobber_t *result = NULL;
8060         asm_clobber_t *last   = NULL;
8061
8062         while(token.type == T_STRING_LITERAL) {
8063                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
8064                 clobber->clobber       = parse_string_literals();
8065
8066                 if (last != NULL) {
8067                         last->next = clobber;
8068                 } else {
8069                         result = clobber;
8070                 }
8071                 last = clobber;
8072
8073                 if (token.type != ',')
8074                         break;
8075                 eat(',');
8076         }
8077
8078         return result;
8079 }
8080
8081 /**
8082  * Parse an asm statement.
8083  */
8084 static statement_t *parse_asm_statement(void)
8085 {
8086         eat(T_asm);
8087
8088         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
8089         statement->base.source_position = token.source_position;
8090
8091         asm_statement_t *asm_statement = &statement->asms;
8092
8093         if (token.type == T_volatile) {
8094                 next_token();
8095                 asm_statement->is_volatile = true;
8096         }
8097
8098         expect('(');
8099         add_anchor_token(')');
8100         add_anchor_token(':');
8101         asm_statement->asm_text = parse_string_literals();
8102
8103         if (token.type != ':') {
8104                 rem_anchor_token(':');
8105                 goto end_of_asm;
8106         }
8107         eat(':');
8108
8109         asm_statement->outputs = parse_asm_arguments(true);
8110         if (token.type != ':') {
8111                 rem_anchor_token(':');
8112                 goto end_of_asm;
8113         }
8114         eat(':');
8115
8116         asm_statement->inputs = parse_asm_arguments(false);
8117         if (token.type != ':') {
8118                 rem_anchor_token(':');
8119                 goto end_of_asm;
8120         }
8121         rem_anchor_token(':');
8122         eat(':');
8123
8124         asm_statement->clobbers = parse_asm_clobbers();
8125
8126 end_of_asm:
8127         rem_anchor_token(')');
8128         expect(')');
8129         expect(';');
8130
8131         if (asm_statement->outputs == NULL) {
8132                 /* GCC: An 'asm' instruction without any output operands will be treated
8133                  * identically to a volatile 'asm' instruction. */
8134                 asm_statement->is_volatile = true;
8135         }
8136
8137         return statement;
8138 end_error:
8139         return create_invalid_statement();
8140 }
8141
8142 /**
8143  * Parse a case statement.
8144  */
8145 static statement_t *parse_case_statement(void)
8146 {
8147         eat(T_case);
8148
8149         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8150         source_position_t *const pos       = &statement->base.source_position;
8151
8152         *pos                             = token.source_position;
8153         statement->case_label.expression = parse_expression();
8154
8155         PUSH_PARENT(statement);
8156
8157         if (c_mode & _GNUC) {
8158                 if (token.type == T_DOTDOTDOT) {
8159                         next_token();
8160                         statement->case_label.end_range = parse_expression();
8161                 }
8162         }
8163
8164         expect(':');
8165
8166         if (! is_constant_expression(statement->case_label.expression)) {
8167                 errorf(pos, "case label does not reduce to an integer constant");
8168         } else if (current_switch != NULL) {
8169                 /* Check for duplicate case values */
8170                 /* FIXME slow */
8171                 long const val = fold_constant(statement->case_label.expression);
8172                 for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
8173                         expression_t const* const e = l->expression;
8174                         if (e == NULL || !is_constant_expression(e) || fold_constant(e) != val)
8175                                 continue;
8176
8177                         errorf(pos, "duplicate case value (previously used %P)",
8178                                &l->base.source_position);
8179                         break;
8180                 }
8181
8182                 /* link all cases into the switch statement */
8183                 if (current_switch->last_case == NULL) {
8184                         current_switch->first_case      = &statement->case_label;
8185                 } else {
8186                         current_switch->last_case->next = &statement->case_label;
8187                 }
8188                 current_switch->last_case = &statement->case_label;
8189         } else {
8190                 errorf(pos, "case label not within a switch statement");
8191         }
8192
8193         statement_t *const inner_stmt = parse_statement();
8194         statement->case_label.statement = inner_stmt;
8195         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8196                 errorf(&inner_stmt->base.source_position, "declaration after case label");
8197         }
8198
8199         POP_PARENT;
8200         return statement;
8201 end_error:
8202         POP_PARENT;
8203         return create_invalid_statement();
8204 }
8205
8206 /**
8207  * Finds an existing default label of a switch statement.
8208  */
8209 static case_label_statement_t *
8210 find_default_label(const switch_statement_t *statement)
8211 {
8212         case_label_statement_t *label = statement->first_case;
8213         for ( ; label != NULL; label = label->next) {
8214                 if (label->expression == NULL)
8215                         return label;
8216         }
8217         return NULL;
8218 }
8219
8220 /**
8221  * Parse a default statement.
8222  */
8223 static statement_t *parse_default_statement(void)
8224 {
8225         eat(T_default);
8226
8227         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8228         statement->base.source_position = token.source_position;
8229
8230         PUSH_PARENT(statement);
8231
8232         expect(':');
8233         if (current_switch != NULL) {
8234                 const case_label_statement_t *def_label = find_default_label(current_switch);
8235                 if (def_label != NULL) {
8236                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
8237                                &def_label->base.source_position);
8238                 } else {
8239                         /* link all cases into the switch statement */
8240                         if (current_switch->last_case == NULL) {
8241                                 current_switch->first_case      = &statement->case_label;
8242                         } else {
8243                                 current_switch->last_case->next = &statement->case_label;
8244                         }
8245                         current_switch->last_case = &statement->case_label;
8246                 }
8247         } else {
8248                 errorf(&statement->base.source_position,
8249                         "'default' label not within a switch statement");
8250         }
8251
8252         statement_t *const inner_stmt = parse_statement();
8253         statement->case_label.statement = inner_stmt;
8254         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8255                 errorf(&inner_stmt->base.source_position, "declaration after default label");
8256         }
8257
8258         POP_PARENT;
8259         return statement;
8260 end_error:
8261         POP_PARENT;
8262         return create_invalid_statement();
8263 }
8264
8265 /**
8266  * Return the declaration for a given label symbol or create a new one.
8267  *
8268  * @param symbol  the symbol of the label
8269  */
8270 static declaration_t *get_label(symbol_t *symbol)
8271 {
8272         declaration_t *candidate = get_declaration(symbol, NAMESPACE_LABEL);
8273         assert(current_function != NULL);
8274         /* if we found a label in the same function, then we already created the
8275          * declaration */
8276         if (candidate != NULL
8277                         && candidate->parent_scope == &current_function->scope) {
8278                 return candidate;
8279         }
8280
8281         /* otherwise we need to create a new one */
8282         declaration_t *const declaration = allocate_declaration_zero();
8283         declaration->namespc       = NAMESPACE_LABEL;
8284         declaration->symbol        = symbol;
8285
8286         label_push(declaration);
8287
8288         return declaration;
8289 }
8290
8291 /**
8292  * Parse a label statement.
8293  */
8294 static statement_t *parse_label_statement(void)
8295 {
8296         assert(token.type == T_IDENTIFIER);
8297         symbol_t *symbol = token.v.symbol;
8298         next_token();
8299
8300         declaration_t *label = get_label(symbol);
8301
8302         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
8303         statement->base.source_position = token.source_position;
8304         statement->label.label          = label;
8305
8306         PUSH_PARENT(statement);
8307
8308         /* if source position is already set then the label is defined twice,
8309          * otherwise it was just mentioned in a goto so far */
8310         if (label->source_position.input_name != NULL) {
8311                 errorf(HERE, "duplicate label '%Y' (declared %P)",
8312                        symbol, &label->source_position);
8313         } else {
8314                 label->source_position = token.source_position;
8315                 label->init.statement  = statement;
8316         }
8317
8318         eat(':');
8319
8320         if (token.type == '}') {
8321                 /* TODO only warn? */
8322                 if (false) {
8323                         warningf(HERE, "label at end of compound statement");
8324                         statement->label.statement = create_empty_statement();
8325                 } else {
8326                         errorf(HERE, "label at end of compound statement");
8327                         statement->label.statement = create_invalid_statement();
8328                 }
8329         } else if (token.type == ';') {
8330                 /* Eat an empty statement here, to avoid the warning about an empty
8331                  * statement after a label.  label:; is commonly used to have a label
8332                  * before a closing brace. */
8333                 statement->label.statement = create_empty_statement();
8334                 next_token();
8335         } else {
8336                 statement_t *const inner_stmt = parse_statement();
8337                 statement->label.statement = inner_stmt;
8338                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
8339                         errorf(&inner_stmt->base.source_position, "declaration after label");
8340                 }
8341         }
8342
8343         /* remember the labels in a list for later checking */
8344         if (label_last == NULL) {
8345                 label_first = &statement->label;
8346         } else {
8347                 label_last->next = &statement->label;
8348         }
8349         label_last = &statement->label;
8350
8351         POP_PARENT;
8352         return statement;
8353 }
8354
8355 /**
8356  * Parse an if statement.
8357  */
8358 static statement_t *parse_if(void)
8359 {
8360         eat(T_if);
8361
8362         statement_t *statement          = allocate_statement_zero(STATEMENT_IF);
8363         statement->base.source_position = token.source_position;
8364
8365         PUSH_PARENT(statement);
8366
8367         expect('(');
8368         add_anchor_token(')');
8369         statement->ifs.condition = parse_expression();
8370         rem_anchor_token(')');
8371         expect(')');
8372
8373         add_anchor_token(T_else);
8374         statement->ifs.true_statement = parse_statement();
8375         rem_anchor_token(T_else);
8376
8377         if (token.type == T_else) {
8378                 next_token();
8379                 statement->ifs.false_statement = parse_statement();
8380         }
8381
8382         POP_PARENT;
8383         return statement;
8384 end_error:
8385         POP_PARENT;
8386         return create_invalid_statement();
8387 }
8388
8389 /**
8390  * Parse a switch statement.
8391  */
8392 static statement_t *parse_switch(void)
8393 {
8394         eat(T_switch);
8395
8396         statement_t *statement          = allocate_statement_zero(STATEMENT_SWITCH);
8397         statement->base.source_position = token.source_position;
8398
8399         PUSH_PARENT(statement);
8400
8401         expect('(');
8402         expression_t *const expr = parse_expression();
8403         type_t       *      type = skip_typeref(expr->base.type);
8404         if (is_type_integer(type)) {
8405                 type = promote_integer(type);
8406         } else if (is_type_valid(type)) {
8407                 errorf(&expr->base.source_position,
8408                        "switch quantity is not an integer, but '%T'", type);
8409                 type = type_error_type;
8410         }
8411         statement->switchs.expression = create_implicit_cast(expr, type);
8412         expect(')');
8413
8414         switch_statement_t *rem = current_switch;
8415         current_switch          = &statement->switchs;
8416         statement->switchs.body = parse_statement();
8417         current_switch          = rem;
8418
8419         if (warning.switch_default &&
8420            find_default_label(&statement->switchs) == NULL) {
8421                 warningf(&statement->base.source_position, "switch has no default case");
8422         }
8423
8424         POP_PARENT;
8425         return statement;
8426 end_error:
8427         POP_PARENT;
8428         return create_invalid_statement();
8429 }
8430
8431 static statement_t *parse_loop_body(statement_t *const loop)
8432 {
8433         statement_t *const rem = current_loop;
8434         current_loop = loop;
8435
8436         statement_t *const body = parse_statement();
8437
8438         current_loop = rem;
8439         return body;
8440 }
8441
8442 /**
8443  * Parse a while statement.
8444  */
8445 static statement_t *parse_while(void)
8446 {
8447         eat(T_while);
8448
8449         statement_t *statement          = allocate_statement_zero(STATEMENT_WHILE);
8450         statement->base.source_position = token.source_position;
8451
8452         PUSH_PARENT(statement);
8453
8454         expect('(');
8455         add_anchor_token(')');
8456         statement->whiles.condition = parse_expression();
8457         rem_anchor_token(')');
8458         expect(')');
8459
8460         statement->whiles.body = parse_loop_body(statement);
8461
8462         POP_PARENT;
8463         return statement;
8464 end_error:
8465         POP_PARENT;
8466         return create_invalid_statement();
8467 }
8468
8469 /**
8470  * Parse a do statement.
8471  */
8472 static statement_t *parse_do(void)
8473 {
8474         eat(T_do);
8475
8476         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
8477         statement->base.source_position = token.source_position;
8478
8479         PUSH_PARENT(statement)
8480
8481         add_anchor_token(T_while);
8482         statement->do_while.body = parse_loop_body(statement);
8483         rem_anchor_token(T_while);
8484
8485         expect(T_while);
8486         expect('(');
8487         add_anchor_token(')');
8488         statement->do_while.condition = parse_expression();
8489         rem_anchor_token(')');
8490         expect(')');
8491         expect(';');
8492
8493         POP_PARENT;
8494         return statement;
8495 end_error:
8496         POP_PARENT;
8497         return create_invalid_statement();
8498 }
8499
8500 /**
8501  * Parse a for statement.
8502  */
8503 static statement_t *parse_for(void)
8504 {
8505         eat(T_for);
8506
8507         statement_t *statement          = allocate_statement_zero(STATEMENT_FOR);
8508         statement->base.source_position = token.source_position;
8509
8510         PUSH_PARENT(statement);
8511
8512         int      top        = environment_top();
8513         scope_t *last_scope = scope;
8514         set_scope(&statement->fors.scope);
8515
8516         expect('(');
8517         add_anchor_token(')');
8518
8519         if (token.type != ';') {
8520                 if (is_declaration_specifier(&token, false)) {
8521                         parse_declaration(record_declaration);
8522                 } else {
8523                         add_anchor_token(';');
8524                         expression_t *const init = parse_expression();
8525                         statement->fors.initialisation = init;
8526                         if (warning.unused_value && !expression_has_effect(init)) {
8527                                 warningf(&init->base.source_position,
8528                                          "initialisation of 'for'-statement has no effect");
8529                         }
8530                         rem_anchor_token(';');
8531                         expect(';');
8532                 }
8533         } else {
8534                 expect(';');
8535         }
8536
8537         if (token.type != ';') {
8538                 add_anchor_token(';');
8539                 statement->fors.condition = parse_expression();
8540                 rem_anchor_token(';');
8541         }
8542         expect(';');
8543         if (token.type != ')') {
8544                 expression_t *const step = parse_expression();
8545                 statement->fors.step = step;
8546                 if (warning.unused_value && !expression_has_effect(step)) {
8547                         warningf(&step->base.source_position,
8548                                  "step of 'for'-statement has no effect");
8549                 }
8550         }
8551         rem_anchor_token(')');
8552         expect(')');
8553         statement->fors.body = parse_loop_body(statement);
8554
8555         assert(scope == &statement->fors.scope);
8556         set_scope(last_scope);
8557         environment_pop_to(top);
8558
8559         POP_PARENT;
8560         return statement;
8561
8562 end_error:
8563         POP_PARENT;
8564         rem_anchor_token(')');
8565         assert(scope == &statement->fors.scope);
8566         set_scope(last_scope);
8567         environment_pop_to(top);
8568
8569         return create_invalid_statement();
8570 }
8571
8572 /**
8573  * Parse a goto statement.
8574  */
8575 static statement_t *parse_goto(void)
8576 {
8577         eat(T_goto);
8578
8579         if (token.type != T_IDENTIFIER) {
8580                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
8581                 eat_statement();
8582                 goto end_error;
8583         }
8584         symbol_t *symbol = token.v.symbol;
8585         next_token();
8586
8587         declaration_t *label = get_label(symbol);
8588
8589         statement_t *statement          = allocate_statement_zero(STATEMENT_GOTO);
8590         statement->base.source_position = token.source_position;
8591
8592         statement->gotos.label = label;
8593
8594         /* remember the goto's in a list for later checking */
8595         if (goto_last == NULL) {
8596                 goto_first = &statement->gotos;
8597         } else {
8598                 goto_last->next = &statement->gotos;
8599         }
8600         goto_last = &statement->gotos;
8601
8602         expect(';');
8603
8604         return statement;
8605 end_error:
8606         return create_invalid_statement();
8607 }
8608
8609 /**
8610  * Parse a continue statement.
8611  */
8612 static statement_t *parse_continue(void)
8613 {
8614         statement_t *statement;
8615         if (current_loop == NULL) {
8616                 errorf(HERE, "continue statement not within loop");
8617                 statement = create_invalid_statement();
8618         } else {
8619                 statement = allocate_statement_zero(STATEMENT_CONTINUE);
8620
8621                 statement->base.source_position = token.source_position;
8622         }
8623
8624         eat(T_continue);
8625         expect(';');
8626
8627         return statement;
8628 end_error:
8629         return create_invalid_statement();
8630 }
8631
8632 /**
8633  * Parse a break statement.
8634  */
8635 static statement_t *parse_break(void)
8636 {
8637         statement_t *statement;
8638         if (current_switch == NULL && current_loop == NULL) {
8639                 errorf(HERE, "break statement not within loop or switch");
8640                 statement = create_invalid_statement();
8641         } else {
8642                 statement = allocate_statement_zero(STATEMENT_BREAK);
8643
8644                 statement->base.source_position = token.source_position;
8645         }
8646
8647         eat(T_break);
8648         expect(';');
8649
8650         return statement;
8651 end_error:
8652         return create_invalid_statement();
8653 }
8654
8655 /**
8656  * Parse a __leave statement.
8657  */
8658 static statement_t *parse_leave(void)
8659 {
8660         statement_t *statement;
8661         if (current_try == NULL) {
8662                 errorf(HERE, "__leave statement not within __try");
8663                 statement = create_invalid_statement();
8664         } else {
8665                 statement = allocate_statement_zero(STATEMENT_LEAVE);
8666
8667                 statement->base.source_position = token.source_position;
8668         }
8669
8670         eat(T___leave);
8671         expect(';');
8672
8673         return statement;
8674 end_error:
8675         return create_invalid_statement();
8676 }
8677
8678 /**
8679  * Check if a given declaration represents a local variable.
8680  */
8681 static bool is_local_var_declaration(const declaration_t *declaration)
8682 {
8683         switch ((storage_class_tag_t) declaration->storage_class) {
8684         case STORAGE_CLASS_AUTO:
8685         case STORAGE_CLASS_REGISTER: {
8686                 const type_t *type = skip_typeref(declaration->type);
8687                 if (is_type_function(type)) {
8688                         return false;
8689                 } else {
8690                         return true;
8691                 }
8692         }
8693         default:
8694                 return false;
8695         }
8696 }
8697
8698 /**
8699  * Check if a given declaration represents a variable.
8700  */
8701 static bool is_var_declaration(const declaration_t *declaration)
8702 {
8703         if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
8704                 return false;
8705
8706         const type_t *type = skip_typeref(declaration->type);
8707         return !is_type_function(type);
8708 }
8709
8710 /**
8711  * Check if a given expression represents a local variable.
8712  */
8713 static bool is_local_variable(const expression_t *expression)
8714 {
8715         if (expression->base.kind != EXPR_REFERENCE) {
8716                 return false;
8717         }
8718         const declaration_t *declaration = expression->reference.declaration;
8719         return is_local_var_declaration(declaration);
8720 }
8721
8722 /**
8723  * Check if a given expression represents a local variable and
8724  * return its declaration then, else return NULL.
8725  */
8726 declaration_t *expr_is_variable(const expression_t *expression)
8727 {
8728         if (expression->base.kind != EXPR_REFERENCE) {
8729                 return NULL;
8730         }
8731         declaration_t *declaration = expression->reference.declaration;
8732         if (is_var_declaration(declaration))
8733                 return declaration;
8734         return NULL;
8735 }
8736
8737 /**
8738  * Parse a return statement.
8739  */
8740 static statement_t *parse_return(void)
8741 {
8742         statement_t *statement          = allocate_statement_zero(STATEMENT_RETURN);
8743         statement->base.source_position = token.source_position;
8744
8745         eat(T_return);
8746
8747         expression_t *return_value = NULL;
8748         if (token.type != ';') {
8749                 return_value = parse_expression();
8750         }
8751         expect(';');
8752
8753         const type_t *const func_type = current_function->type;
8754         assert(is_type_function(func_type));
8755         type_t *const return_type = skip_typeref(func_type->function.return_type);
8756
8757         if (return_value != NULL) {
8758                 type_t *return_value_type = skip_typeref(return_value->base.type);
8759
8760                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)
8761                                 && !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
8762                         warningf(&statement->base.source_position,
8763                                  "'return' with a value, in function returning void");
8764                         return_value = NULL;
8765                 } else {
8766                         assign_error_t error = semantic_assign(return_type, return_value);
8767                         report_assign_error(error, return_type, return_value, "'return'",
8768                                             &statement->base.source_position);
8769                         return_value = create_implicit_cast(return_value, return_type);
8770                 }
8771                 /* check for returning address of a local var */
8772                 if (return_value != NULL &&
8773                                 return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
8774                         const expression_t *expression = return_value->unary.value;
8775                         if (is_local_variable(expression)) {
8776                                 warningf(&statement->base.source_position,
8777                                          "function returns address of local variable");
8778                         }
8779                 }
8780         } else {
8781                 if (!is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
8782                         warningf(&statement->base.source_position,
8783                                  "'return' without value, in function returning non-void");
8784                 }
8785         }
8786         statement->returns.value = return_value;
8787
8788         return statement;
8789 end_error:
8790         return create_invalid_statement();
8791 }
8792
8793 /**
8794  * Parse a declaration statement.
8795  */
8796 static statement_t *parse_declaration_statement(void)
8797 {
8798         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
8799
8800         statement->base.source_position = token.source_position;
8801
8802         declaration_t *before = last_declaration;
8803         parse_declaration(record_declaration);
8804
8805         if (before == NULL) {
8806                 statement->declaration.declarations_begin = scope->declarations;
8807         } else {
8808                 statement->declaration.declarations_begin = before->next;
8809         }
8810         statement->declaration.declarations_end = last_declaration;
8811
8812         return statement;
8813 }
8814
8815 /**
8816  * Parse an expression statement, ie. expr ';'.
8817  */
8818 static statement_t *parse_expression_statement(void)
8819 {
8820         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
8821
8822         statement->base.source_position  = token.source_position;
8823         expression_t *const expr         = parse_expression();
8824         statement->expression.expression = expr;
8825
8826         expect(';');
8827
8828         return statement;
8829 end_error:
8830         return create_invalid_statement();
8831 }
8832
8833 /**
8834  * Parse a microsoft __try { } __finally { } or
8835  * __try{ } __except() { }
8836  */
8837 static statement_t *parse_ms_try_statment(void)
8838 {
8839         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
8840
8841         statement->base.source_position  = token.source_position;
8842         eat(T___try);
8843
8844         ms_try_statement_t *rem = current_try;
8845         current_try = &statement->ms_try;
8846         statement->ms_try.try_statement = parse_compound_statement(false);
8847         current_try = rem;
8848
8849         if (token.type == T___except) {
8850                 eat(T___except);
8851                 expect('(');
8852                 add_anchor_token(')');
8853                 expression_t *const expr = parse_expression();
8854                 type_t       *      type = skip_typeref(expr->base.type);
8855                 if (is_type_integer(type)) {
8856                         type = promote_integer(type);
8857                 } else if (is_type_valid(type)) {
8858                         errorf(&expr->base.source_position,
8859                                "__expect expression is not an integer, but '%T'", type);
8860                         type = type_error_type;
8861                 }
8862                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
8863                 rem_anchor_token(')');
8864                 expect(')');
8865                 statement->ms_try.final_statement = parse_compound_statement(false);
8866         } else if (token.type == T__finally) {
8867                 eat(T___finally);
8868                 statement->ms_try.final_statement = parse_compound_statement(false);
8869         } else {
8870                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
8871                 return create_invalid_statement();
8872         }
8873         return statement;
8874 end_error:
8875         return create_invalid_statement();
8876 }
8877
8878 static statement_t *parse_empty_statement(void)
8879 {
8880         if (warning.empty_statement) {
8881                 warningf(HERE, "statement is empty");
8882         }
8883         eat(';');
8884         return create_empty_statement();
8885 }
8886
8887 /**
8888  * Parse a statement.
8889  * There's also parse_statement() which additionally checks for
8890  * "statement has no effect" warnings
8891  */
8892 static statement_t *intern_parse_statement(void)
8893 {
8894         statement_t *statement = NULL;
8895
8896         /* declaration or statement */
8897         add_anchor_token(';');
8898         switch (token.type) {
8899         case T_IDENTIFIER:
8900                 if (look_ahead(1)->type == ':') {
8901                         statement = parse_label_statement();
8902                 } else if (is_typedef_symbol(token.v.symbol)) {
8903                         statement = parse_declaration_statement();
8904                 } else {
8905                         statement = parse_expression_statement();
8906                 }
8907                 break;
8908
8909         case T___extension__:
8910                 /* This can be a prefix to a declaration or an expression statement.
8911                  * We simply eat it now and parse the rest with tail recursion. */
8912                 do {
8913                         next_token();
8914                 } while (token.type == T___extension__);
8915                 statement = parse_statement();
8916                 break;
8917
8918         DECLARATION_START
8919                 statement = parse_declaration_statement();
8920                 break;
8921
8922         case ';':        statement = parse_empty_statement();         break;
8923         case '{':        statement = parse_compound_statement(false); break;
8924         case T___leave:  statement = parse_leave();                   break;
8925         case T___try:    statement = parse_ms_try_statment();         break;
8926         case T_asm:      statement = parse_asm_statement();           break;
8927         case T_break:    statement = parse_break();                   break;
8928         case T_case:     statement = parse_case_statement();          break;
8929         case T_continue: statement = parse_continue();                break;
8930         case T_default:  statement = parse_default_statement();       break;
8931         case T_do:       statement = parse_do();                      break;
8932         case T_for:      statement = parse_for();                     break;
8933         case T_goto:     statement = parse_goto();                    break;
8934         case T_if:       statement = parse_if ();                     break;
8935         case T_return:   statement = parse_return();                  break;
8936         case T_switch:   statement = parse_switch();                  break;
8937         case T_while:    statement = parse_while();                   break;
8938         default:         statement = parse_expression_statement();    break;
8939         }
8940         rem_anchor_token(';');
8941
8942         assert(statement != NULL
8943                         && statement->base.source_position.input_name != NULL);
8944
8945         return statement;
8946 }
8947
8948 /**
8949  * parse a statement and emits "statement has no effect" warning if needed
8950  * (This is really a wrapper around intern_parse_statement with check for 1
8951  *  single warning. It is needed, because for statement expressions we have
8952  *  to avoid the warning on the last statement)
8953  */
8954 static statement_t *parse_statement(void)
8955 {
8956         statement_t *statement = intern_parse_statement();
8957
8958         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
8959                 expression_t *expression = statement->expression.expression;
8960                 if (!expression_has_effect(expression)) {
8961                         warningf(&expression->base.source_position,
8962                                         "statement has no effect");
8963                 }
8964         }
8965
8966         return statement;
8967 }
8968
8969 /**
8970  * Parse a compound statement.
8971  */
8972 static statement_t *parse_compound_statement(bool inside_expression_statement)
8973 {
8974         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
8975         statement->base.source_position = token.source_position;
8976
8977         PUSH_PARENT(statement);
8978
8979         eat('{');
8980         add_anchor_token('}');
8981
8982         int      top        = environment_top();
8983         scope_t *last_scope = scope;
8984         set_scope(&statement->compound.scope);
8985
8986         statement_t *last_statement = NULL;
8987
8988         bool only_decls_so_far = true;
8989         while (token.type != '}' && token.type != T_EOF) {
8990                 statement_t *sub_statement = intern_parse_statement();
8991                 if (is_invalid_statement(sub_statement)) {
8992                         /* an error occurred. if we are at an anchor, return */
8993                         if (at_anchor())
8994                                 goto end_error;
8995                         continue;
8996                 }
8997
8998                 if (warning.declaration_after_statement) {
8999                         if (sub_statement->kind != STATEMENT_DECLARATION) {
9000                                 only_decls_so_far = false;
9001                         } else if (!only_decls_so_far) {
9002                                 warningf(&sub_statement->base.source_position,
9003                                          "ISO C90 forbids mixed declarations and code");
9004                         }
9005                 }
9006
9007                 if (last_statement != NULL) {
9008                         last_statement->base.next = sub_statement;
9009                 } else {
9010                         statement->compound.statements = sub_statement;
9011                 }
9012
9013                 while (sub_statement->base.next != NULL)
9014                         sub_statement = sub_statement->base.next;
9015
9016                 last_statement = sub_statement;
9017         }
9018
9019         if (token.type == '}') {
9020                 next_token();
9021         } else {
9022                 errorf(&statement->base.source_position,
9023                        "end of file while looking for closing '}'");
9024         }
9025
9026         /* look over all statements again to produce no effect warnings */
9027         if (warning.unused_value) {
9028                 statement_t *sub_statement = statement->compound.statements;
9029                 for( ; sub_statement != NULL; sub_statement = sub_statement->base.next) {
9030                         if (sub_statement->kind != STATEMENT_EXPRESSION)
9031                                 continue;
9032                         /* don't emit a warning for the last expression in an expression
9033                          * statement as it has always an effect */
9034                         if (inside_expression_statement && sub_statement->base.next == NULL)
9035                                 continue;
9036
9037                         expression_t *expression = sub_statement->expression.expression;
9038                         if (!expression_has_effect(expression)) {
9039                                 warningf(&expression->base.source_position,
9040                                          "statement has no effect");
9041                         }
9042                 }
9043         }
9044
9045 end_error:
9046         rem_anchor_token('}');
9047         assert(scope == &statement->compound.scope);
9048         set_scope(last_scope);
9049         environment_pop_to(top);
9050
9051         POP_PARENT;
9052         return statement;
9053 }
9054
9055 /**
9056  * Initialize builtin types.
9057  */
9058 static void initialize_builtin_types(void)
9059 {
9060         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
9061         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
9062         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
9063         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
9064         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
9065         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
9066         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    type_int);
9067         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
9068
9069         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
9070         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
9071         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
9072         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
9073 }
9074
9075 /**
9076  * Check for unused global static functions and variables
9077  */
9078 static void check_unused_globals(void)
9079 {
9080         if (!warning.unused_function && !warning.unused_variable)
9081                 return;
9082
9083         for (const declaration_t *decl = global_scope->declarations; decl != NULL; decl = decl->next) {
9084                 if (decl->used                  ||
9085                     decl->modifiers & DM_UNUSED ||
9086                     decl->modifiers & DM_USED   ||
9087                     decl->storage_class != STORAGE_CLASS_STATIC)
9088                         continue;
9089
9090                 type_t *const type = decl->type;
9091                 const char *s;
9092                 if (is_type_function(skip_typeref(type))) {
9093                         if (!warning.unused_function || decl->is_inline)
9094                                 continue;
9095
9096                         s = (decl->init.statement != NULL ? "defined" : "declared");
9097                 } else {
9098                         if (!warning.unused_variable)
9099                                 continue;
9100
9101                         s = "defined";
9102                 }
9103
9104                 warningf(&decl->source_position, "'%#T' %s but not used",
9105                         type, decl->symbol, s);
9106         }
9107 }
9108
9109 static void parse_global_asm(void)
9110 {
9111         eat(T_asm);
9112         expect('(');
9113
9114         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
9115         statement->base.source_position = token.source_position;
9116         statement->asms.asm_text        = parse_string_literals();
9117         statement->base.next            = unit->global_asm;
9118         unit->global_asm                = statement;
9119
9120         expect(')');
9121         expect(';');
9122
9123 end_error:;
9124 }
9125
9126 /**
9127  * Parse a translation unit.
9128  */
9129 static void parse_translation_unit(void)
9130 {
9131         for (;;) switch (token.type) {
9132                 DECLARATION_START
9133                 case T_IDENTIFIER:
9134                 case T___extension__:
9135                         parse_external_declaration();
9136                         break;
9137
9138                 case T_asm:
9139                         parse_global_asm();
9140                         break;
9141
9142                 case T_EOF:
9143                         return;
9144
9145                 case ';':
9146                         /* TODO error in strict mode */
9147                         warningf(HERE, "stray ';' outside of function");
9148                         next_token();
9149                         break;
9150
9151                 default:
9152                         errorf(HERE, "stray %K outside of function", &token);
9153                         if (token.type == '(' || token.type == '{' || token.type == '[')
9154                                 eat_until_matching_token(token.type);
9155                         next_token();
9156                         break;
9157         }
9158 }
9159
9160 /**
9161  * Parse the input.
9162  *
9163  * @return  the translation unit or NULL if errors occurred.
9164  */
9165 void start_parsing(void)
9166 {
9167         environment_stack = NEW_ARR_F(stack_entry_t, 0);
9168         label_stack       = NEW_ARR_F(stack_entry_t, 0);
9169         diagnostic_count  = 0;
9170         error_count       = 0;
9171         warning_count     = 0;
9172
9173         type_set_output(stderr);
9174         ast_set_output(stderr);
9175
9176         assert(unit == NULL);
9177         unit = allocate_ast_zero(sizeof(unit[0]));
9178
9179         assert(global_scope == NULL);
9180         global_scope = &unit->scope;
9181
9182         assert(scope == NULL);
9183         set_scope(&unit->scope);
9184
9185         initialize_builtin_types();
9186 }
9187
9188 translation_unit_t *finish_parsing(void)
9189 {
9190         assert(scope == &unit->scope);
9191         scope          = NULL;
9192         last_declaration = NULL;
9193
9194         assert(global_scope == &unit->scope);
9195         check_unused_globals();
9196         global_scope = NULL;
9197
9198         DEL_ARR_F(environment_stack);
9199         DEL_ARR_F(label_stack);
9200
9201         translation_unit_t *result = unit;
9202         unit = NULL;
9203         return result;
9204 }
9205
9206 void parse(void)
9207 {
9208         lookahead_bufpos = 0;
9209         for(int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
9210                 next_token();
9211         }
9212         parse_translation_unit();
9213 }
9214
9215 /**
9216  * Initialize the parser.
9217  */
9218 void init_parser(void)
9219 {
9220         if (c_mode & _MS) {
9221                 /* add predefined symbols for extended-decl-modifier */
9222                 sym_align      = symbol_table_insert("align");
9223                 sym_allocate   = symbol_table_insert("allocate");
9224                 sym_dllimport  = symbol_table_insert("dllimport");
9225                 sym_dllexport  = symbol_table_insert("dllexport");
9226                 sym_naked      = symbol_table_insert("naked");
9227                 sym_noinline   = symbol_table_insert("noinline");
9228                 sym_noreturn   = symbol_table_insert("noreturn");
9229                 sym_nothrow    = symbol_table_insert("nothrow");
9230                 sym_novtable   = symbol_table_insert("novtable");
9231                 sym_property   = symbol_table_insert("property");
9232                 sym_get        = symbol_table_insert("get");
9233                 sym_put        = symbol_table_insert("put");
9234                 sym_selectany  = symbol_table_insert("selectany");
9235                 sym_thread     = symbol_table_insert("thread");
9236                 sym_uuid       = symbol_table_insert("uuid");
9237                 sym_deprecated = symbol_table_insert("deprecated");
9238                 sym_restrict   = symbol_table_insert("restrict");
9239                 sym_noalias    = symbol_table_insert("noalias");
9240         }
9241         memset(token_anchor_set, 0, sizeof(token_anchor_set));
9242
9243         init_expression_parsers();
9244         obstack_init(&temp_obst);
9245
9246         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
9247         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
9248 }
9249
9250 /**
9251  * Terminate the parser.
9252  */
9253 void exit_parser(void)
9254 {
9255         obstack_free(&temp_obst, NULL);
9256 }