nsz Git - cparser/blob - parser.c

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