nsz Git - cparser/blob - parser.c

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