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