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         declaration->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                 declaration->modifiers |= parse_attributes(&attributes);
3792         }
3793
3794         construct_type_t *inner_types = NULL;
3795
3796         switch(token.type) {
3797         case T_IDENTIFIER:
3798                 if (declaration == NULL) {
3799                         errorf(HERE, "no identifier expected in typename");
3800                 } else {
3801                         declaration->symbol          = token.v.symbol;
3802                         declaration->source_position = token.source_position;
3803                 }
3804                 next_token();
3805                 break;
3806         case '(':
3807                 next_token();
3808                 add_anchor_token(')');
3809                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
3810                 rem_anchor_token(')');
3811                 expect(')');
3812                 break;
3813         default:
3814                 if (may_be_abstract)
3815                         break;
3816                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
3817                 /* avoid a loop in the outermost scope, because eat_statement doesn't
3818                  * eat '}' */
3819                 if (token.type == '}' && current_function == NULL) {
3820                         next_token();
3821                 } else {
3822                         eat_statement();
3823                 }
3824                 return NULL;
3825         }
3826
3827         construct_type_t *p = last;
3828
3829         while(true) {
3830                 construct_type_t *type;
3831                 switch(token.type) {
3832                 case '(':
3833                         type = parse_function_declarator(declaration);
3834                         break;
3835                 case '[':
3836                         type = parse_array_declarator();
3837                         break;
3838                 default:
3839                         goto declarator_finished;
3840                 }
3841
3842                 /* insert in the middle of the list (behind p) */
3843                 if (p != NULL) {
3844                         type->next = p->next;
3845                         p->next    = type;
3846                 } else {
3847                         type->next = first;
3848                         first      = type;
3849                 }
3850                 if (last == p) {
3851                         last = type;
3852                 }
3853         }
3854
3855 declarator_finished:
3856         /* append inner_types at the end of the list, we don't to set last anymore
3857          * as it's not needed anymore */
3858         if (last == NULL) {
3859                 assert(first == NULL);
3860                 first = inner_types;
3861         } else {
3862                 last->next = inner_types;
3863         }
3864
3865         return first;
3866 end_error:
3867         return NULL;
3868 }
3869
3870 static void parse_declaration_attributes(declaration_t *declaration)
3871 {
3872         gnu_attribute_t  *attributes = NULL;
3873         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
3874
3875         if (declaration == NULL)
3876                 return;
3877
3878         declaration->modifiers |= modifiers;
3879         /* check if we have these stupid mode attributes... */
3880         type_t *old_type = declaration->type;
3881         if (old_type == NULL)
3882                 return;
3883
3884         gnu_attribute_t *attribute = attributes;
3885         for ( ; attribute != NULL; attribute = attribute->next) {
3886                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
3887                         continue;
3888
3889                 atomic_type_kind_t  akind = attribute->u.akind;
3890                 if (!is_type_signed(old_type)) {
3891                         switch(akind) {
3892                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
3893                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
3894                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
3895                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
3896                         default:
3897                                 panic("invalid akind in mode attribute");
3898                         }
3899                 }
3900                 declaration->type
3901                         = make_atomic_type(akind, old_type->base.qualifiers);
3902         }
3903 }
3904
3905 static type_t *construct_declarator_type(construct_type_t *construct_list,
3906                                          type_t *type)
3907 {
3908         construct_type_t *iter = construct_list;
3909         for( ; iter != NULL; iter = iter->next) {
3910                 switch(iter->kind) {
3911                 case CONSTRUCT_INVALID:
3912                         internal_errorf(HERE, "invalid type construction found");
3913                 case CONSTRUCT_FUNCTION: {
3914                         construct_function_type_t *construct_function_type
3915                                 = (construct_function_type_t*) iter;
3916
3917                         type_t *function_type = construct_function_type->function_type;
3918
3919                         function_type->function.return_type = type;
3920
3921                         type_t *skipped_return_type = skip_typeref(type);
3922                         if (is_type_function(skipped_return_type)) {
3923                                 errorf(HERE, "function returning function is not allowed");
3924                                 type = type_error_type;
3925                         } else if (is_type_array(skipped_return_type)) {
3926                                 errorf(HERE, "function returning array is not allowed");
3927                                 type = type_error_type;
3928                         } else {
3929                                 type = function_type;
3930                         }
3931                         break;
3932                 }
3933
3934                 case CONSTRUCT_POINTER: {
3935                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
3936                         type_t           *pointer_type   = allocate_type_zero(TYPE_POINTER, &null_position);
3937                         pointer_type->pointer.points_to  = type;
3938                         pointer_type->base.qualifiers    = parsed_pointer->type_qualifiers;
3939
3940                         type = pointer_type;
3941                         break;
3942                 }
3943
3944                 case CONSTRUCT_ARRAY: {
3945                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
3946                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY, &null_position);
3947
3948                         expression_t *size_expression = parsed_array->size;
3949                         if (size_expression != NULL) {
3950                                 size_expression
3951                                         = create_implicit_cast(size_expression, type_size_t);
3952                         }
3953
3954                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
3955                         array_type->array.element_type    = type;
3956                         array_type->array.is_static       = parsed_array->is_static;
3957                         array_type->array.is_variable     = parsed_array->is_variable;
3958                         array_type->array.size_expression = size_expression;
3959
3960                         if (size_expression != NULL) {
3961                                 if (is_constant_expression(size_expression)) {
3962                                         array_type->array.size_constant = true;
3963                                         array_type->array.size
3964                                                 = fold_constant(size_expression);
3965                                 } else {
3966                                         array_type->array.is_vla = true;
3967                                 }
3968                         }
3969
3970                         type_t *skipped_type = skip_typeref(type);
3971                         if (is_type_atomic(skipped_type, ATOMIC_TYPE_VOID)) {
3972                                 errorf(HERE, "array of void is not allowed");
3973                                 type = type_error_type;
3974                         } else {
3975                                 type = array_type;
3976                         }
3977                         break;
3978                 }
3979                 }
3980
3981                 type_t *hashed_type = typehash_insert(type);
3982                 if (hashed_type != type) {
3983                         /* the function type was constructed earlier freeing it here will
3984                          * destroy other types... */
3985                         if (iter->kind != CONSTRUCT_FUNCTION) {
3986                                 free_type(type);
3987                         }
3988                         type = hashed_type;
3989                 }
3990         }
3991
3992         return type;
3993 }
3994
3995 static declaration_t *parse_declarator(
3996                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
3997 {
3998         declaration_t *const declaration    = allocate_declaration_zero();
3999         declaration->declared_storage_class = specifiers->declared_storage_class;
4000         declaration->modifiers              = specifiers->modifiers;
4001         declaration->deprecated_string      = specifiers->deprecated_string;
4002         declaration->get_property_sym       = specifiers->get_property_sym;
4003         declaration->put_property_sym       = specifiers->put_property_sym;
4004         declaration->is_inline              = specifiers->is_inline;
4005
4006         declaration->storage_class          = specifiers->declared_storage_class;
4007         if (declaration->storage_class == STORAGE_CLASS_NONE
4008                         && scope != global_scope) {
4009                 declaration->storage_class = STORAGE_CLASS_AUTO;
4010         }
4011
4012         if (specifiers->alignment != 0) {
4013                 /* TODO: add checks here */
4014                 declaration->alignment = specifiers->alignment;
4015         }
4016
4017         construct_type_t *construct_type
4018                 = parse_inner_declarator(declaration, may_be_abstract);
4019         type_t *const type = specifiers->type;
4020         declaration->type = construct_declarator_type(construct_type, type);
4021
4022         parse_declaration_attributes(declaration);
4023
4024         fix_declaration_type(declaration);
4025
4026         if (construct_type != NULL) {
4027                 obstack_free(&temp_obst, construct_type);
4028         }
4029
4030         return declaration;
4031 }
4032
4033 static type_t *parse_abstract_declarator(type_t *base_type)
4034 {
4035         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4036
4037         type_t *result = construct_declarator_type(construct_type, base_type);
4038         if (construct_type != NULL) {
4039                 obstack_free(&temp_obst, construct_type);
4040         }
4041
4042         return result;
4043 }
4044
4045 static declaration_t *append_declaration(declaration_t* const declaration)
4046 {
4047         if (last_declaration != NULL) {
4048                 last_declaration->next = declaration;
4049         } else {
4050                 scope->declarations = declaration;
4051         }
4052         last_declaration = declaration;
4053         return declaration;
4054 }
4055
4056 /**
4057  * Check if the declaration of main is suspicious.  main should be a
4058  * function with external linkage, returning int, taking either zero
4059  * arguments, two, or three arguments of appropriate types, ie.
4060  *
4061  * int main([ int argc, char **argv [, char **env ] ]).
4062  *
4063  * @param decl    the declaration to check
4064  * @param type    the function type of the declaration
4065  */
4066 static void check_type_of_main(const declaration_t *const decl, const function_type_t *const func_type)
4067 {
4068         if (decl->storage_class == STORAGE_CLASS_STATIC) {
4069                 warningf(&decl->source_position,
4070                          "'main' is normally a non-static function");
4071         }
4072         if (skip_typeref(func_type->return_type) != type_int) {
4073                 warningf(&decl->source_position,
4074                          "return type of 'main' should be 'int', but is '%T'",
4075                          func_type->return_type);
4076         }
4077         const function_parameter_t *parm = func_type->parameters;
4078         if (parm != NULL) {
4079                 type_t *const first_type = parm->type;
4080                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4081                         warningf(&decl->source_position,
4082                                  "first argument of 'main' should be 'int', but is '%T'", first_type);
4083                 }
4084                 parm = parm->next;
4085                 if (parm != NULL) {
4086                         type_t *const second_type = parm->type;
4087                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4088                                 warningf(&decl->source_position,
4089                                          "second argument of 'main' should be 'char**', but is '%T'", second_type);
4090                         }
4091                         parm = parm->next;
4092                         if (parm != NULL) {
4093                                 type_t *const third_type = parm->type;
4094                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4095                                         warningf(&decl->source_position,
4096                                                  "third argument of 'main' should be 'char**', but is '%T'", third_type);
4097                                 }
4098                                 parm = parm->next;
4099                                 if (parm != NULL)
4100                                         goto warn_arg_count;
4101                         }
4102                 } else {
4103 warn_arg_count:
4104                         warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
4105                 }
4106         }
4107 }
4108
4109 /**
4110  * Check if a symbol is the equal to "main".
4111  */
4112 static bool is_sym_main(const symbol_t *const sym)
4113 {
4114         return strcmp(sym->string, "main") == 0;
4115 }
4116
4117 static declaration_t *internal_record_declaration(
4118         declaration_t *const declaration,
4119         const bool is_definition)
4120 {
4121         const symbol_t *const symbol  = declaration->symbol;
4122         const namespace_t     namespc = (namespace_t)declaration->namespc;
4123
4124         assert(symbol != NULL);
4125         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4126
4127         type_t *const orig_type = declaration->type;
4128         type_t *const type      = skip_typeref(orig_type);
4129         if (is_type_function(type) &&
4130                         type->function.unspecified_parameters &&
4131                         warning.strict_prototypes &&
4132                         previous_declaration == NULL) {
4133                 warningf(&declaration->source_position,
4134                          "function declaration '%#T' is not a prototype",
4135                          orig_type, declaration->symbol);
4136         }
4137
4138         if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
4139                 check_type_of_main(declaration, &type->function);
4140         }
4141
4142         if (warning.nested_externs                             &&
4143             declaration->storage_class == STORAGE_CLASS_EXTERN &&
4144             scope                      != global_scope) {
4145                 warningf(&declaration->source_position,
4146                          "nested extern declaration of '%#T'", declaration->type, symbol);
4147         }
4148
4149         assert(declaration != previous_declaration);
4150         if (previous_declaration != NULL
4151                         && previous_declaration->parent_scope == scope) {
4152                 /* can happen for K&R style declarations */
4153                 if (previous_declaration->type == NULL) {
4154                         previous_declaration->type = declaration->type;
4155                 }
4156
4157                 const type_t *prev_type = skip_typeref(previous_declaration->type);
4158                 if (!types_compatible(type, prev_type)) {
4159                         errorf(&declaration->source_position,
4160                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
4161                                    orig_type, symbol, previous_declaration->type, symbol,
4162                                    &previous_declaration->source_position);
4163                 } else {
4164                         unsigned old_storage_class = previous_declaration->storage_class;
4165                         if (old_storage_class == STORAGE_CLASS_ENUM_ENTRY) {
4166                                 errorf(&declaration->source_position,
4167                                            "redeclaration of enum entry '%Y' (declared %P)",
4168                                            symbol, &previous_declaration->source_position);
4169                                 return previous_declaration;
4170                         }
4171
4172                         if (warning.redundant_decls                                     &&
4173                             is_definition                                               &&
4174                             previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
4175                             !(previous_declaration->modifiers & DM_USED)                &&
4176                             !previous_declaration->used) {
4177                                 warningf(&previous_declaration->source_position,
4178                                          "unnecessary static forward declaration for '%#T'",
4179                                          previous_declaration->type, symbol);
4180                         }
4181
4182                         unsigned new_storage_class = declaration->storage_class;
4183
4184                         if (is_type_incomplete(prev_type)) {
4185                                 previous_declaration->type = type;
4186                                 prev_type                  = type;
4187                         }
4188
4189                         /* pretend no storage class means extern for function
4190                          * declarations (except if the previous declaration is neither
4191                          * none nor extern) */
4192                         if (is_type_function(type)) {
4193                                 if (prev_type->function.unspecified_parameters) {
4194                                         previous_declaration->type = type;
4195                                         prev_type                  = type;
4196                                 }
4197
4198                                 switch (old_storage_class) {
4199                                 case STORAGE_CLASS_NONE:
4200                                         old_storage_class = STORAGE_CLASS_EXTERN;
4201                                         /* FALLTHROUGH */
4202
4203                                 case STORAGE_CLASS_EXTERN:
4204                                         if (is_definition) {
4205                                                 if (warning.missing_prototypes &&
4206                                                     prev_type->function.unspecified_parameters &&
4207                                                     !is_sym_main(symbol)) {
4208                                                         warningf(&declaration->source_position,
4209                                                                          "no previous prototype for '%#T'",
4210                                                                          orig_type, symbol);
4211                                                 }
4212                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4213                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4214                                         }
4215                                         break;
4216
4217                                 default:
4218                                         break;
4219                                 }
4220                         }
4221
4222                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
4223                                         new_storage_class == STORAGE_CLASS_EXTERN) {
4224 warn_redundant_declaration:
4225                                 if (!is_definition          &&
4226                                     warning.redundant_decls &&
4227                                     strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
4228                                         warningf(&declaration->source_position,
4229                                                  "redundant declaration for '%Y' (declared %P)",
4230                                                  symbol, &previous_declaration->source_position);
4231                                 }
4232                         } else if (current_function == NULL) {
4233                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
4234                                     new_storage_class == STORAGE_CLASS_STATIC) {
4235                                         errorf(&declaration->source_position,
4236                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
4237                                                symbol, &previous_declaration->source_position);
4238                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4239                                         previous_declaration->storage_class          = STORAGE_CLASS_NONE;
4240                                         previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
4241                                 } else {
4242                                         goto warn_redundant_declaration;
4243                                 }
4244                         } else if (old_storage_class == new_storage_class) {
4245                                 errorf(&declaration->source_position,
4246                                        "redeclaration of '%Y' (declared %P)",
4247                                        symbol, &previous_declaration->source_position);
4248                         } else {
4249                                 errorf(&declaration->source_position,
4250                                        "redeclaration of '%Y' with different linkage (declared %P)",
4251                                        symbol, &previous_declaration->source_position);
4252                         }
4253                 }
4254
4255                 previous_declaration->modifiers |= declaration->modifiers;
4256                 previous_declaration->is_inline |= declaration->is_inline;
4257                 return previous_declaration;
4258         } else if (is_type_function(type)) {
4259                 if (is_definition &&
4260                     declaration->storage_class != STORAGE_CLASS_STATIC) {
4261                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4262                                 warningf(&declaration->source_position,
4263                                          "no previous prototype for '%#T'", orig_type, symbol);
4264                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4265                                 warningf(&declaration->source_position,
4266                                          "no previous declaration for '%#T'", orig_type,
4267                                          symbol);
4268                         }
4269                 }
4270         } else {
4271                 if (warning.missing_declarations &&
4272                     scope == global_scope && (
4273                       declaration->storage_class == STORAGE_CLASS_NONE ||
4274                       declaration->storage_class == STORAGE_CLASS_THREAD
4275                     )) {
4276                         warningf(&declaration->source_position,
4277                                  "no previous declaration for '%#T'", orig_type, symbol);
4278                 }
4279         }
4280
4281         assert(declaration->parent_scope == NULL);
4282         assert(scope != NULL);
4283
4284         declaration->parent_scope = scope;
4285
4286         environment_push(declaration);
4287         return append_declaration(declaration);
4288 }
4289
4290 static declaration_t *record_declaration(declaration_t *declaration)
4291 {
4292         return internal_record_declaration(declaration, false);
4293 }
4294
4295 static declaration_t *record_definition(declaration_t *declaration)
4296 {
4297         return internal_record_declaration(declaration, true);
4298 }
4299
4300 static void parser_error_multiple_definition(declaration_t *declaration,
4301                 const source_position_t *source_position)
4302 {
4303         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
4304                declaration->symbol, &declaration->source_position);
4305 }
4306
4307 static bool is_declaration_specifier(const token_t *token,
4308                                      bool only_specifiers_qualifiers)
4309 {
4310         switch(token->type) {
4311                 TYPE_SPECIFIERS
4312                 TYPE_QUALIFIERS
4313                         return true;
4314                 case T_IDENTIFIER:
4315                         return is_typedef_symbol(token->v.symbol);
4316
4317                 case T___extension__:
4318                 STORAGE_CLASSES
4319                         return !only_specifiers_qualifiers;
4320
4321                 default:
4322                         return false;
4323         }
4324 }
4325
4326 static void parse_init_declarator_rest(declaration_t *declaration)
4327 {
4328         eat('=');
4329
4330         type_t *orig_type = declaration->type;
4331         type_t *type      = skip_typeref(orig_type);
4332
4333         if (declaration->init.initializer != NULL) {
4334                 parser_error_multiple_definition(declaration, HERE);
4335         }
4336
4337         bool must_be_constant = false;
4338         if (declaration->storage_class == STORAGE_CLASS_STATIC
4339                         || declaration->storage_class == STORAGE_CLASS_THREAD_STATIC
4340                         || declaration->parent_scope == global_scope) {
4341                 must_be_constant = true;
4342         }
4343
4344         parse_initializer_env_t env;
4345         env.type             = orig_type;
4346         env.must_be_constant = must_be_constant;
4347         env.declaration      = declaration;
4348
4349         initializer_t *initializer = parse_initializer(&env);
4350
4351         if (env.type != orig_type) {
4352                 orig_type         = env.type;
4353                 type              = skip_typeref(orig_type);
4354                 declaration->type = env.type;
4355         }
4356
4357         if (is_type_function(type)) {
4358                 errorf(&declaration->source_position,
4359                        "initializers not allowed for function types at declator '%Y' (type '%T')",
4360                        declaration->symbol, orig_type);
4361         } else {
4362                 declaration->init.initializer = initializer;
4363         }
4364 }
4365
4366 /* parse rest of a declaration without any declarator */
4367 static void parse_anonymous_declaration_rest(
4368                 const declaration_specifiers_t *specifiers,
4369                 parsed_declaration_func finished_declaration)
4370 {
4371         eat(';');
4372
4373         declaration_t *const declaration    = allocate_declaration_zero();
4374         declaration->type                   = specifiers->type;
4375         declaration->declared_storage_class = specifiers->declared_storage_class;
4376         declaration->source_position        = specifiers->source_position;
4377         declaration->modifiers              = specifiers->modifiers;
4378
4379         if (declaration->declared_storage_class != STORAGE_CLASS_NONE) {
4380                 warningf(&declaration->source_position,
4381                          "useless storage class in empty declaration");
4382         }
4383         declaration->storage_class = STORAGE_CLASS_NONE;
4384
4385         type_t *type = declaration->type;
4386         switch (type->kind) {
4387                 case TYPE_COMPOUND_STRUCT:
4388                 case TYPE_COMPOUND_UNION: {
4389                         if (type->compound.declaration->symbol == NULL) {
4390                                 warningf(&declaration->source_position,
4391                                          "unnamed struct/union that defines no instances");
4392                         }
4393                         break;
4394                 }
4395
4396                 case TYPE_ENUM:
4397                         break;
4398
4399                 default:
4400                         warningf(&declaration->source_position, "empty declaration");
4401                         break;
4402         }
4403
4404         finished_declaration(declaration);
4405 }
4406
4407 static void parse_declaration_rest(declaration_t *ndeclaration,
4408                 const declaration_specifiers_t *specifiers,
4409                 parsed_declaration_func finished_declaration)
4410 {
4411         add_anchor_token(';');
4412         add_anchor_token('=');
4413         add_anchor_token(',');
4414         while(true) {
4415                 declaration_t *declaration = finished_declaration(ndeclaration);
4416
4417                 type_t *orig_type = declaration->type;
4418                 type_t *type      = skip_typeref(orig_type);
4419
4420                 if (type->kind != TYPE_FUNCTION &&
4421                     declaration->is_inline &&
4422                     is_type_valid(type)) {
4423                         warningf(&declaration->source_position,
4424                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
4425                 }
4426
4427                 if (token.type == '=') {
4428                         parse_init_declarator_rest(declaration);
4429                 }
4430
4431                 if (token.type != ',')
4432                         break;
4433                 eat(',');
4434
4435                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
4436         }
4437         expect(';');
4438
4439 end_error:
4440         rem_anchor_token(';');
4441         rem_anchor_token('=');
4442         rem_anchor_token(',');
4443 }
4444
4445 static declaration_t *finished_kr_declaration(declaration_t *declaration)
4446 {
4447         symbol_t *symbol  = declaration->symbol;
4448         if (symbol == NULL) {
4449                 errorf(HERE, "anonymous declaration not valid as function parameter");
4450                 return declaration;
4451         }
4452         namespace_t namespc = (namespace_t) declaration->namespc;
4453         if (namespc != NAMESPACE_NORMAL) {
4454                 return record_declaration(declaration);
4455         }
4456
4457         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4458         if (previous_declaration == NULL ||
4459                         previous_declaration->parent_scope != scope) {
4460                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4461                        symbol);
4462                 return declaration;
4463         }
4464
4465         if (previous_declaration->type == NULL) {
4466                 previous_declaration->type          = declaration->type;
4467                 previous_declaration->declared_storage_class = declaration->declared_storage_class;
4468                 previous_declaration->storage_class = declaration->storage_class;
4469                 previous_declaration->parent_scope  = scope;
4470                 return previous_declaration;
4471         } else {
4472                 return record_declaration(declaration);
4473         }
4474 }
4475
4476 static void parse_declaration(parsed_declaration_func finished_declaration)
4477 {
4478         declaration_specifiers_t specifiers;
4479         memset(&specifiers, 0, sizeof(specifiers));
4480         parse_declaration_specifiers(&specifiers);
4481
4482         if (token.type == ';') {
4483                 parse_anonymous_declaration_rest(&specifiers, append_declaration);
4484         } else {
4485                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
4486                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
4487         }
4488 }
4489
4490 static type_t *get_default_promoted_type(type_t *orig_type)
4491 {
4492         type_t *result = orig_type;
4493
4494         type_t *type = skip_typeref(orig_type);
4495         if (is_type_integer(type)) {
4496                 result = promote_integer(type);
4497         } else if (type == type_float) {
4498                 result = type_double;
4499         }
4500
4501         return result;
4502 }
4503
4504 static void parse_kr_declaration_list(declaration_t *declaration)
4505 {
4506         type_t *type = skip_typeref(declaration->type);
4507         if (!is_type_function(type))
4508                 return;
4509
4510         if (!type->function.kr_style_parameters)
4511                 return;
4512
4513         /* push function parameters */
4514         int       top        = environment_top();
4515         scope_t  *last_scope = scope;
4516         set_scope(&declaration->scope);
4517
4518         declaration_t *parameter = declaration->scope.declarations;
4519         for ( ; parameter != NULL; parameter = parameter->next) {
4520                 assert(parameter->parent_scope == NULL);
4521                 parameter->parent_scope = scope;
4522                 environment_push(parameter);
4523         }
4524
4525         /* parse declaration list */
4526         while (is_declaration_specifier(&token, false)) {
4527                 parse_declaration(finished_kr_declaration);
4528         }
4529
4530         /* pop function parameters */
4531         assert(scope == &declaration->scope);
4532         set_scope(last_scope);
4533         environment_pop_to(top);
4534
4535         /* update function type */
4536         type_t *new_type = duplicate_type(type);
4537
4538         function_parameter_t *parameters     = NULL;
4539         function_parameter_t *last_parameter = NULL;
4540
4541         declaration_t *parameter_declaration = declaration->scope.declarations;
4542         for( ; parameter_declaration != NULL;
4543                         parameter_declaration = parameter_declaration->next) {
4544                 type_t *parameter_type = parameter_declaration->type;
4545                 if (parameter_type == NULL) {
4546                         if (strict_mode) {
4547                                 errorf(HERE, "no type specified for function parameter '%Y'",
4548                                        parameter_declaration->symbol);
4549                         } else {
4550                                 if (warning.implicit_int) {
4551                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
4552                                                 parameter_declaration->symbol);
4553                                 }
4554                                 parameter_type              = type_int;
4555                                 parameter_declaration->type = parameter_type;
4556                         }
4557                 }
4558
4559                 semantic_parameter(parameter_declaration);
4560                 parameter_type = parameter_declaration->type;
4561
4562                 /*
4563                  * we need the default promoted types for the function type
4564                  */
4565                 parameter_type = get_default_promoted_type(parameter_type);
4566
4567                 function_parameter_t *function_parameter
4568                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
4569                 memset(function_parameter, 0, sizeof(function_parameter[0]));
4570
4571                 function_parameter->type = parameter_type;
4572                 if (last_parameter != NULL) {
4573                         last_parameter->next = function_parameter;
4574                 } else {
4575                         parameters = function_parameter;
4576                 }
4577                 last_parameter = function_parameter;
4578         }
4579
4580         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
4581          * prototype */
4582         new_type->function.parameters             = parameters;
4583         new_type->function.unspecified_parameters = true;
4584
4585         type = typehash_insert(new_type);
4586         if (type != new_type) {
4587                 obstack_free(type_obst, new_type);
4588         }
4589
4590         declaration->type = type;
4591 }
4592
4593 static bool first_err = true;
4594
4595 /**
4596  * When called with first_err set, prints the name of the current function,
4597  * else does noting.
4598  */
4599 static void print_in_function(void)
4600 {
4601         if (first_err) {
4602                 first_err = false;
4603                 diagnosticf("%s: In function '%Y':\n",
4604                         current_function->source_position.input_name,
4605                         current_function->symbol);
4606         }
4607 }
4608
4609 /**
4610  * Check if all labels are defined in the current function.
4611  * Check if all labels are used in the current function.
4612  */
4613 static void check_labels(void)
4614 {
4615         for (const goto_statement_t *goto_statement = goto_first;
4616             goto_statement != NULL;
4617             goto_statement = goto_statement->next) {
4618                 declaration_t *label = goto_statement->label;
4619
4620                 label->used = true;
4621                 if (label->source_position.input_name == NULL) {
4622                         print_in_function();
4623                         errorf(&goto_statement->base.source_position,
4624                                "label '%Y' used but not defined", label->symbol);
4625                  }
4626         }
4627         goto_first = goto_last = NULL;
4628
4629         if (warning.unused_label) {
4630                 for (const label_statement_t *label_statement = label_first;
4631                          label_statement != NULL;
4632                          label_statement = label_statement->next) {
4633                         const declaration_t *label = label_statement->label;
4634
4635                         if (! label->used) {
4636                                 print_in_function();
4637                                 warningf(&label_statement->base.source_position,
4638                                         "label '%Y' defined but not used", label->symbol);
4639                         }
4640                 }
4641         }
4642         label_first = label_last = NULL;
4643 }
4644
4645 /**
4646  * Check declarations of current_function for unused entities.
4647  */
4648 static void check_declarations(void)
4649 {
4650         if (warning.unused_parameter) {
4651                 const scope_t *scope = &current_function->scope;
4652
4653                 const declaration_t *parameter = scope->declarations;
4654                 for (; parameter != NULL; parameter = parameter->next) {
4655                         if (! parameter->used) {
4656                                 print_in_function();
4657                                 warningf(&parameter->source_position,
4658                                          "unused parameter '%Y'", parameter->symbol);
4659                         }
4660                 }
4661         }
4662         if (warning.unused_variable) {
4663         }
4664 }
4665
4666 static int determine_truth(expression_t const* const cond)
4667 {
4668         return
4669                 !is_constant_expression(cond) ? 0 :
4670                 fold_constant(cond) != 0      ? 1 :
4671                 -1;
4672 }
4673
4674 static void check_reachable(statement_t *const stmt)
4675 {
4676         if (stmt->base.reachable)
4677                 return;
4678         if (stmt->kind != STATEMENT_DO_WHILE)
4679                 stmt->base.reachable = true;
4680
4681         statement_t *last = stmt;
4682         statement_t *next;
4683         switch (stmt->kind) {
4684                 case STATEMENT_INVALID:
4685                 case STATEMENT_EMPTY:
4686                 case STATEMENT_DECLARATION:
4687                 case STATEMENT_ASM:
4688                         next = stmt->base.next;
4689                         break;
4690
4691                 case STATEMENT_COMPOUND:
4692                         next = stmt->compound.statements;
4693                         break;
4694
4695                 case STATEMENT_RETURN:
4696                         return;
4697
4698                 case STATEMENT_IF: {
4699                         if_statement_t const* const ifs = &stmt->ifs;
4700                         int            const        val = determine_truth(ifs->condition);
4701
4702                         if (val >= 0)
4703                                 check_reachable(ifs->true_statement);
4704
4705                         if (val > 0)
4706                                 return;
4707
4708                         if (ifs->false_statement != NULL) {
4709                                 check_reachable(ifs->false_statement);
4710                                 return;
4711                         }
4712
4713                         next = stmt->base.next;
4714                         break;
4715                 }
4716
4717                 case STATEMENT_SWITCH: {
4718                         switch_statement_t const *const switchs = &stmt->switchs;
4719                         expression_t       const *const expr    = switchs->expression;
4720
4721                         if (is_constant_expression(expr)) {
4722                                 long                    const val      = fold_constant(expr);
4723                                 case_label_statement_t *      defaults = NULL;
4724                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4725                                         if (i->expression == NULL) {
4726                                                 defaults = i;
4727                                                 continue;
4728                                         }
4729
4730                                         expression_t *const case_expr = i->expression;
4731                                         if (is_constant_expression(case_expr) &&
4732                                             fold_constant(case_expr) == val) {
4733                                                 check_reachable((statement_t*)i);
4734                                                 return;
4735                                         }
4736                                 }
4737
4738                                 if (defaults != NULL) {
4739                                         check_reachable((statement_t*)defaults);
4740                                         return;
4741                                 }
4742                         } else {
4743                                 bool has_default = false;
4744                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4745                                         if (i->expression == NULL)
4746                                                 has_default = true;
4747
4748                                         check_reachable((statement_t*)i);
4749                                 }
4750
4751                                 if (has_default)
4752                                         return;
4753                         }
4754
4755                         next = stmt->base.next;
4756                         break;
4757                 }
4758
4759                 case STATEMENT_EXPRESSION: {
4760                         /* Check for noreturn function call */
4761                         expression_t const *const expr = stmt->expression.expression;
4762                         if (expr->kind == EXPR_CALL) {
4763                                 expression_t const *const func = expr->call.function;
4764                                 if (func->kind == EXPR_REFERENCE) {
4765                                         declaration_t const *const decl = func->reference.declaration;
4766                                         if (decl != NULL && decl->modifiers & DM_NORETURN) {
4767                                                 return;
4768                                         }
4769                                 }
4770                         }
4771
4772                         next = stmt->base.next;
4773                         break;
4774                 }
4775
4776                 case STATEMENT_CONTINUE: {
4777                         statement_t *parent = stmt;
4778                         for (;;) {
4779                                 parent = parent->base.parent;
4780                                 if (parent == NULL) /* continue not within loop */
4781                                         return;
4782
4783                                 next = parent;
4784                                 switch (parent->kind) {
4785                                         case STATEMENT_WHILE:    goto continue_while;
4786                                         case STATEMENT_DO_WHILE: goto continue_do_while;
4787                                         case STATEMENT_FOR:      goto continue_for;
4788
4789                                         default: break;
4790                                 }
4791                         }
4792                 }
4793
4794                 case STATEMENT_BREAK: {
4795                         statement_t *parent = stmt;
4796                         for (;;) {
4797                                 parent = parent->base.parent;
4798                                 if (parent == NULL) /* break not within loop/switch */
4799                                         return;
4800
4801                                 switch (parent->kind) {
4802                                         case STATEMENT_SWITCH:
4803                                         case STATEMENT_WHILE:
4804                                         case STATEMENT_DO_WHILE:
4805                                         case STATEMENT_FOR:
4806                                                 next = parent->base.next;
4807                                                 goto found_break_parent;
4808
4809                                         default: break;
4810                                 }
4811                         }
4812 found_break_parent:
4813                         break;
4814                 }
4815
4816                 case STATEMENT_GOTO:
4817                         next = stmt->gotos.label->init.statement;
4818                         if (next == NULL) /* missing label */
4819                                 return;
4820                         break;
4821
4822                 case STATEMENT_LABEL:
4823                         next = stmt->label.statement;
4824                         break;
4825
4826                 case STATEMENT_CASE_LABEL:
4827                         next = stmt->case_label.statement;
4828                         break;
4829
4830                 case STATEMENT_WHILE: {
4831                         while_statement_t const *const whiles = &stmt->whiles;
4832                         int                      const val    = determine_truth(whiles->condition);
4833
4834                         if (val >= 0)
4835                                 check_reachable(whiles->body);
4836
4837                         if (val > 0)
4838                                 return;
4839
4840                         next = stmt->base.next;
4841                         break;
4842                 }
4843
4844                 case STATEMENT_DO_WHILE:
4845                         next = stmt->do_while.body;
4846                         break;
4847
4848                 case STATEMENT_FOR: {
4849                         for_statement_t *const fors = &stmt->fors;
4850
4851                         if (fors->condition_reachable)
4852                                 return;
4853                         fors->condition_reachable = true;
4854
4855                         expression_t const *const cond = fors->condition;
4856                         int          const        val  =
4857                                 cond == NULL ? 1 : determine_truth(cond);
4858
4859                         if (val >= 0)
4860                                 check_reachable(fors->body);
4861
4862                         if (val > 0)
4863                                 return;
4864
4865                         next = stmt->base.next;
4866                         break;
4867                 }
4868
4869                 case STATEMENT_MS_TRY:
4870                 case STATEMENT_LEAVE:
4871                         panic("unimplemented");
4872         }
4873
4874         while (next == NULL) {
4875                 next = last->base.parent;
4876                 if (next == NULL) {
4877                         type_t *const type = current_function->type;
4878                         assert(is_type_function(type));
4879                         type_t *const ret  = skip_typeref(type->function.return_type);
4880                         if (warning.return_type                    &&
4881                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
4882                             !is_sym_main(current_function->symbol)) {
4883                                 warningf(&stmt->base.source_position,
4884                                          "control reaches end of non-void function");
4885                         }
4886                         return;
4887                 }
4888
4889                 switch (next->kind) {
4890                         case STATEMENT_INVALID:
4891                         case STATEMENT_EMPTY:
4892                         case STATEMENT_DECLARATION:
4893                         case STATEMENT_EXPRESSION:
4894                         case STATEMENT_ASM:
4895                         case STATEMENT_RETURN:
4896                         case STATEMENT_CONTINUE:
4897                         case STATEMENT_BREAK:
4898                         case STATEMENT_GOTO:
4899                         case STATEMENT_LEAVE:
4900                                 panic("invalid control flow in function");
4901
4902                         case STATEMENT_COMPOUND:
4903                         case STATEMENT_IF:
4904                         case STATEMENT_SWITCH:
4905                         case STATEMENT_LABEL:
4906                         case STATEMENT_CASE_LABEL:
4907                                 last = next;
4908                                 next = next->base.next;
4909                                 break;
4910
4911                         case STATEMENT_WHILE: {
4912 continue_while:
4913                                 if (next->base.reachable)
4914                                         return;
4915                                 next->base.reachable = true;
4916
4917                                 while_statement_t const *const whiles = &next->whiles;
4918                                 int                      const val    = determine_truth(whiles->condition);
4919
4920                                 if (val >= 0)
4921                                         check_reachable(whiles->body);
4922
4923                                 if (val > 0)
4924                                         return;
4925
4926                                 last = next;
4927                                 next = next->base.next;
4928                                 break;
4929                         }
4930
4931                         case STATEMENT_DO_WHILE: {
4932 continue_do_while:
4933                                 if (next->base.reachable)
4934                                         return;
4935                                 next->base.reachable = true;
4936
4937                                 do_while_statement_t const *const dw  = &next->do_while;
4938                                 int                  const        val = determine_truth(dw->condition);
4939
4940                                 if (val >= 0)
4941                                         check_reachable(dw->body);
4942
4943                                 if (val > 0)
4944                                         return;
4945
4946                                 last = next;
4947                                 next = next->base.next;
4948                                 break;
4949                         }
4950
4951                         case STATEMENT_FOR: {
4952 continue_for:;
4953                                 for_statement_t *const fors = &next->fors;
4954
4955                                 fors->step_reachable = true;
4956
4957                                 if (fors->condition_reachable)
4958                                         return;
4959                                 fors->condition_reachable = true;
4960
4961                                 expression_t const *const cond = fors->condition;
4962                                 int          const        val  =
4963                                         cond == NULL ? 1 : determine_truth(cond);
4964
4965                                 if (val >= 0)
4966                                         check_reachable(fors->body);
4967
4968                                 if (val > 0)
4969                                         return;
4970
4971                                 last = next;
4972                                 next = next->base.next;
4973                                 break;
4974                         }
4975
4976                         case STATEMENT_MS_TRY:
4977                                 panic("unimplemented");
4978                 }
4979         }
4980
4981         if (next == NULL) {
4982                 next = stmt->base.parent;
4983                 if (next == NULL) {
4984                         warningf(&stmt->base.source_position,
4985                                  "control reaches end of non-void function");
4986                 }
4987         }
4988
4989         check_reachable(next);
4990 }
4991
4992 static void check_unreachable(statement_t const* const stmt)
4993 {
4994         if (!stmt->base.reachable            &&
4995             stmt->kind != STATEMENT_COMPOUND &&
4996             stmt->kind != STATEMENT_DO_WHILE &&
4997             stmt->kind != STATEMENT_FOR) {
4998                 warningf(&stmt->base.source_position,
4999                          "statement is unreachable");
5000         }
5001
5002         switch (stmt->kind) {
5003                 case STATEMENT_INVALID:
5004                 case STATEMENT_EMPTY:
5005                 case STATEMENT_RETURN:
5006                 case STATEMENT_DECLARATION:
5007                 case STATEMENT_EXPRESSION:
5008                 case STATEMENT_CONTINUE:
5009                 case STATEMENT_BREAK:
5010                 case STATEMENT_GOTO:
5011                 case STATEMENT_ASM:
5012                 case STATEMENT_LEAVE:
5013                         break;
5014
5015                 case STATEMENT_COMPOUND:
5016                         if (stmt->compound.statements)
5017                                 check_unreachable(stmt->compound.statements);
5018                         break;
5019
5020                 case STATEMENT_IF:
5021                         check_unreachable(stmt->ifs.true_statement);
5022                         if (stmt->ifs.false_statement != NULL)
5023                                 check_unreachable(stmt->ifs.false_statement);
5024                         break;
5025
5026                 case STATEMENT_SWITCH:
5027                         check_unreachable(stmt->switchs.body);
5028                         break;
5029
5030                 case STATEMENT_LABEL:
5031                         check_unreachable(stmt->label.statement);
5032                         break;
5033
5034                 case STATEMENT_CASE_LABEL:
5035                         check_unreachable(stmt->case_label.statement);
5036                         break;
5037
5038                 case STATEMENT_WHILE:
5039                         check_unreachable(stmt->whiles.body);
5040                         break;
5041
5042                 case STATEMENT_DO_WHILE:
5043                         check_unreachable(stmt->do_while.body);
5044                         if (!stmt->base.reachable) {
5045                                 expression_t const *const cond = stmt->do_while.condition;
5046                                 if (determine_truth(cond) >= 0) {
5047                                         warningf(&cond->base.source_position,
5048                                                  "condition of do-while-loop is unreachable");
5049                                 }
5050                         }
5051                         break;
5052
5053                 case STATEMENT_FOR: {
5054                         for_statement_t const* const fors = &stmt->fors;
5055
5056                         if (!stmt->base.reachable && fors->initialisation != NULL) {
5057                                 warningf(&fors->initialisation->base.source_position,
5058                                          "initialisation of for-statement is unreachable");
5059                         }
5060
5061                         if (!fors->condition_reachable && fors->condition != NULL) {
5062                                 warningf(&fors->condition->base.source_position,
5063                                          "condition of for-statement is unreachable");
5064                         }
5065
5066                         if (!fors->step_reachable && fors->step != NULL) {
5067                                 warningf(&fors->step->base.source_position,
5068                                          "step of for-statement is unreachable");
5069                         }
5070
5071                         check_unreachable(stmt->fors.body);
5072                         break;
5073                 }
5074
5075                 case STATEMENT_MS_TRY:
5076                         panic("unimplemented");
5077         }
5078
5079         if (stmt->base.next)
5080                 check_unreachable(stmt->base.next);
5081 }
5082
5083 static void parse_external_declaration(void)
5084 {
5085         /* function-definitions and declarations both start with declaration
5086          * specifiers */
5087         declaration_specifiers_t specifiers;
5088         memset(&specifiers, 0, sizeof(specifiers));
5089
5090         add_anchor_token(';');
5091         parse_declaration_specifiers(&specifiers);
5092         rem_anchor_token(';');
5093
5094         /* must be a declaration */
5095         if (token.type == ';') {
5096                 parse_anonymous_declaration_rest(&specifiers, append_declaration);
5097                 return;
5098         }
5099
5100         add_anchor_token(',');
5101         add_anchor_token('=');
5102         rem_anchor_token(';');
5103
5104         /* declarator is common to both function-definitions and declarations */
5105         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5106
5107         rem_anchor_token(',');
5108         rem_anchor_token('=');
5109         rem_anchor_token(';');
5110
5111         /* must be a declaration */
5112         switch (token.type) {
5113                 case ',':
5114                 case ';':
5115                         parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
5116                         return;
5117
5118                 case '=':
5119                         parse_declaration_rest(ndeclaration, &specifiers, record_definition);
5120                         return;
5121         }
5122
5123         /* must be a function definition */
5124         parse_kr_declaration_list(ndeclaration);
5125
5126         if (token.type != '{') {
5127                 parse_error_expected("while parsing function definition", '{', NULL);
5128                 eat_until_matching_token(';');
5129                 return;
5130         }
5131
5132         type_t *type = ndeclaration->type;
5133
5134         /* note that we don't skip typerefs: the standard doesn't allow them here
5135          * (so we can't use is_type_function here) */
5136         if (type->kind != TYPE_FUNCTION) {
5137                 if (is_type_valid(type)) {
5138                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5139                                type, ndeclaration->symbol);
5140                 }
5141                 eat_block();
5142                 return;
5143         }
5144
5145         /* § 6.7.5.3 (14) a function definition with () means no
5146          * parameters (and not unspecified parameters) */
5147         if (type->function.unspecified_parameters
5148                         && type->function.parameters == NULL
5149                         && !type->function.kr_style_parameters) {
5150                 type_t *duplicate = duplicate_type(type);
5151                 duplicate->function.unspecified_parameters = false;
5152
5153                 type = typehash_insert(duplicate);
5154                 if (type != duplicate) {
5155                         obstack_free(type_obst, duplicate);
5156                 }
5157                 ndeclaration->type = type;
5158         }
5159
5160         declaration_t *const declaration = record_definition(ndeclaration);
5161         if (ndeclaration != declaration) {
5162                 declaration->scope = ndeclaration->scope;
5163         }
5164         type = skip_typeref(declaration->type);
5165
5166         /* push function parameters and switch scope */
5167         int       top        = environment_top();
5168         scope_t  *last_scope = scope;
5169         set_scope(&declaration->scope);
5170
5171         declaration_t *parameter = declaration->scope.declarations;
5172         for( ; parameter != NULL; parameter = parameter->next) {
5173                 if (parameter->parent_scope == &ndeclaration->scope) {
5174                         parameter->parent_scope = scope;
5175                 }
5176                 assert(parameter->parent_scope == NULL
5177                                 || parameter->parent_scope == scope);
5178                 parameter->parent_scope = scope;
5179                 if (parameter->symbol == NULL) {
5180                         errorf(&ndeclaration->source_position, "parameter name omitted");
5181                         continue;
5182                 }
5183                 environment_push(parameter);
5184         }
5185
5186         if (declaration->init.statement != NULL) {
5187                 parser_error_multiple_definition(declaration, HERE);
5188                 eat_block();
5189         } else {
5190                 /* parse function body */
5191                 int            label_stack_top      = label_top();
5192                 declaration_t *old_current_function = current_function;
5193                 current_function                    = declaration;
5194                 current_parent                      = NULL;
5195
5196                 statement_t *const body = parse_compound_statement(false);
5197                 declaration->init.statement = body;
5198                 first_err = true;
5199                 check_labels();
5200                 check_declarations();
5201                 if (warning.return_type || warning.unreachable_code) {
5202                         check_reachable(body);
5203                         if (warning.unreachable_code)
5204                                 check_unreachable(body);
5205                 }
5206
5207                 assert(current_parent   == NULL);
5208                 assert(current_function == declaration);
5209                 current_function = old_current_function;
5210                 label_pop_to(label_stack_top);
5211         }
5212
5213         assert(scope == &declaration->scope);
5214         set_scope(last_scope);
5215         environment_pop_to(top);
5216 }
5217
5218 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5219                                   source_position_t *source_position)
5220 {
5221         type_t *type = allocate_type_zero(TYPE_BITFIELD, source_position);
5222
5223         type->bitfield.base_type = base_type;
5224         type->bitfield.size      = size;
5225
5226         return type;
5227 }
5228
5229 static declaration_t *find_compound_entry(declaration_t *compound_declaration,
5230                                           symbol_t *symbol)
5231 {
5232         declaration_t *iter = compound_declaration->scope.declarations;
5233         for( ; iter != NULL; iter = iter->next) {
5234                 if (iter->namespc != NAMESPACE_NORMAL)
5235                         continue;
5236
5237                 if (iter->symbol == NULL) {
5238                         type_t *type = skip_typeref(iter->type);
5239                         if (is_type_compound(type)) {
5240                                 declaration_t *result
5241                                         = find_compound_entry(type->compound.declaration, symbol);
5242                                 if (result != NULL)
5243                                         return result;
5244                         }
5245                         continue;
5246                 }
5247
5248                 if (iter->symbol == symbol) {
5249                         return iter;
5250                 }
5251         }
5252
5253         return NULL;
5254 }
5255
5256 static void parse_compound_declarators(declaration_t *struct_declaration,
5257                 const declaration_specifiers_t *specifiers)
5258 {
5259         declaration_t *last_declaration = struct_declaration->scope.declarations;
5260         if (last_declaration != NULL) {
5261                 while(last_declaration->next != NULL) {
5262                         last_declaration = last_declaration->next;
5263                 }
5264         }
5265
5266         while(1) {
5267                 declaration_t *declaration;
5268
5269                 if (token.type == ':') {
5270                         source_position_t source_position = *HERE;
5271                         next_token();
5272
5273                         type_t *base_type = specifiers->type;
5274                         expression_t *size = parse_constant_expression();
5275
5276                         if (!is_type_integer(skip_typeref(base_type))) {
5277                                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5278                                        base_type);
5279                         }
5280
5281                         type_t *type = make_bitfield_type(base_type, size, &source_position);
5282
5283                         declaration                         = allocate_declaration_zero();
5284                         declaration->namespc                = NAMESPACE_NORMAL;
5285                         declaration->declared_storage_class = STORAGE_CLASS_NONE;
5286                         declaration->storage_class          = STORAGE_CLASS_NONE;
5287                         declaration->source_position        = source_position;
5288                         declaration->modifiers              = specifiers->modifiers;
5289                         declaration->type                   = type;
5290                 } else {
5291                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
5292
5293                         type_t *orig_type = declaration->type;
5294                         type_t *type      = skip_typeref(orig_type);
5295
5296                         if (token.type == ':') {
5297                                 source_position_t source_position = *HERE;
5298                                 next_token();
5299                                 expression_t *size = parse_constant_expression();
5300
5301                                 if (!is_type_integer(type)) {
5302                                         errorf(HERE, "bitfield base type '%T' is not an "
5303                                                "integer type", orig_type);
5304                                 }
5305
5306                                 type_t *bitfield_type = make_bitfield_type(orig_type, size, &source_position);
5307                                 declaration->type = bitfield_type;
5308                         } else {
5309                                 /* TODO we ignore arrays for now... what is missing is a check
5310                                  * that they're at the end of the struct */
5311                                 if (is_type_incomplete(type) && !is_type_array(type)) {
5312                                         errorf(HERE,
5313                                                "compound member '%Y' has incomplete type '%T'",
5314                                                declaration->symbol, orig_type);
5315                                 } else if (is_type_function(type)) {
5316                                         errorf(HERE, "compound member '%Y' must not have function "
5317                                                "type '%T'", declaration->symbol, orig_type);
5318                                 }
5319                         }
5320                 }
5321
5322                 /* make sure we don't define a symbol multiple times */
5323                 symbol_t *symbol = declaration->symbol;
5324                 if (symbol != NULL) {
5325                         declaration_t *prev_decl
5326                                 = find_compound_entry(struct_declaration, symbol);
5327
5328                         if (prev_decl != NULL) {
5329                                 assert(prev_decl->symbol == symbol);
5330                                 errorf(&declaration->source_position,
5331                                        "multiple declarations of symbol '%Y' (declared %P)",
5332                                        symbol, &prev_decl->source_position);
5333                         }
5334                 }
5335
5336                 /* append declaration */
5337                 if (last_declaration != NULL) {
5338                         last_declaration->next = declaration;
5339                 } else {
5340                         struct_declaration->scope.declarations = declaration;
5341                 }
5342                 last_declaration = declaration;
5343
5344                 if (token.type != ',')
5345                         break;
5346                 next_token();
5347         }
5348         expect(';');
5349
5350 end_error:
5351         ;
5352 }
5353
5354 static void parse_compound_type_entries(declaration_t *compound_declaration)
5355 {
5356         eat('{');
5357         add_anchor_token('}');
5358
5359         while(token.type != '}' && token.type != T_EOF) {
5360                 declaration_specifiers_t specifiers;
5361                 memset(&specifiers, 0, sizeof(specifiers));
5362                 parse_declaration_specifiers(&specifiers);
5363
5364                 parse_compound_declarators(compound_declaration, &specifiers);
5365         }
5366         rem_anchor_token('}');
5367
5368         if (token.type == T_EOF) {
5369                 errorf(HERE, "EOF while parsing struct");
5370         }
5371         next_token();
5372 }
5373
5374 static type_t *parse_typename(void)
5375 {
5376         declaration_specifiers_t specifiers;
5377         memset(&specifiers, 0, sizeof(specifiers));
5378         parse_declaration_specifiers(&specifiers);
5379         if (specifiers.declared_storage_class != STORAGE_CLASS_NONE) {
5380                 /* TODO: improve error message, user does probably not know what a
5381                  * storage class is...
5382                  */
5383                 errorf(HERE, "typename may not have a storage class");
5384         }
5385
5386         type_t *result = parse_abstract_declarator(specifiers.type);
5387
5388         return result;
5389 }
5390
5391
5392
5393
5394 typedef expression_t* (*parse_expression_function) (unsigned precedence);
5395 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
5396                                                           expression_t *left);
5397
5398 typedef struct expression_parser_function_t expression_parser_function_t;
5399 struct expression_parser_function_t {
5400         unsigned                         precedence;
5401         parse_expression_function        parser;
5402         unsigned                         infix_precedence;
5403         parse_expression_infix_function  infix_parser;
5404 };
5405
5406 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5407
5408 /**
5409  * Prints an error message if an expression was expected but not read
5410  */
5411 static expression_t *expected_expression_error(void)
5412 {
5413         /* skip the error message if the error token was read */
5414         if (token.type != T_ERROR) {
5415                 errorf(HERE, "expected expression, got token '%K'", &token);
5416         }
5417         next_token();
5418
5419         return create_invalid_expression();
5420 }
5421
5422 /**
5423  * Parse a string constant.
5424  */
5425 static expression_t *parse_string_const(void)
5426 {
5427         wide_string_t wres;
5428         if (token.type == T_STRING_LITERAL) {
5429                 string_t res = token.v.string;
5430                 next_token();
5431                 while (token.type == T_STRING_LITERAL) {
5432                         res = concat_strings(&res, &token.v.string);
5433                         next_token();
5434                 }
5435                 if (token.type != T_WIDE_STRING_LITERAL) {
5436                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
5437                         /* note: that we use type_char_ptr here, which is already the
5438                          * automatic converted type. revert_automatic_type_conversion
5439                          * will construct the array type */
5440                         cnst->base.type    = type_char_ptr;
5441                         cnst->string.value = res;
5442                         return cnst;
5443                 }
5444
5445                 wres = concat_string_wide_string(&res, &token.v.wide_string);
5446         } else {
5447                 wres = token.v.wide_string;
5448         }
5449         next_token();
5450
5451         for (;;) {
5452                 switch (token.type) {
5453                         case T_WIDE_STRING_LITERAL:
5454                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
5455                                 break;
5456
5457                         case T_STRING_LITERAL:
5458                                 wres = concat_wide_string_string(&wres, &token.v.string);
5459                                 break;
5460
5461                         default: {
5462                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
5463                                 cnst->base.type         = type_wchar_t_ptr;
5464                                 cnst->wide_string.value = wres;
5465                                 return cnst;
5466                         }
5467                 }
5468                 next_token();
5469         }
5470 }
5471
5472 /**
5473  * Parse an integer constant.
5474  */
5475 static expression_t *parse_int_const(void)
5476 {
5477         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5478         cnst->base.source_position = *HERE;
5479         cnst->base.type            = token.datatype;
5480         cnst->conste.v.int_value   = token.v.intvalue;
5481
5482         next_token();
5483
5484         return cnst;
5485 }
5486
5487 /**
5488  * Parse a character constant.
5489  */
5490 static expression_t *parse_character_constant(void)
5491 {
5492         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
5493
5494         cnst->base.source_position = *HERE;
5495         cnst->base.type            = token.datatype;
5496         cnst->conste.v.character   = token.v.string;
5497
5498         if (cnst->conste.v.character.size != 1) {
5499                 if (warning.multichar && (c_mode & _GNUC)) {
5500                         /* TODO */
5501                         warningf(HERE, "multi-character character constant");
5502                 } else {
5503                         errorf(HERE, "more than 1 characters in character constant");
5504                 }
5505         }
5506         next_token();
5507
5508         return cnst;
5509 }
5510
5511 /**
5512  * Parse a wide character constant.
5513  */
5514 static expression_t *parse_wide_character_constant(void)
5515 {
5516         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
5517
5518         cnst->base.source_position    = *HERE;
5519         cnst->base.type               = token.datatype;
5520         cnst->conste.v.wide_character = token.v.wide_string;
5521
5522         if (cnst->conste.v.wide_character.size != 1) {
5523                 if (warning.multichar && (c_mode & _GNUC)) {
5524                         /* TODO */
5525                         warningf(HERE, "multi-character character constant");
5526                 } else {
5527                         errorf(HERE, "more than 1 characters in character constant");
5528                 }
5529         }
5530         next_token();
5531
5532         return cnst;
5533 }
5534
5535 /**
5536  * Parse a float constant.
5537  */
5538 static expression_t *parse_float_const(void)
5539 {
5540         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5541         cnst->base.type            = token.datatype;
5542         cnst->conste.v.float_value = token.v.floatvalue;
5543
5544         next_token();
5545
5546         return cnst;
5547 }
5548
5549 static declaration_t *create_implicit_function(symbol_t *symbol,
5550                 const source_position_t *source_position)
5551 {
5552         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION, source_position);
5553         ntype->function.return_type            = type_int;
5554         ntype->function.unspecified_parameters = true;
5555
5556         type_t *type = typehash_insert(ntype);
5557         if (type != ntype) {
5558                 free_type(ntype);
5559         }
5560
5561         declaration_t *const declaration    = allocate_declaration_zero();
5562         declaration->storage_class          = STORAGE_CLASS_EXTERN;
5563         declaration->declared_storage_class = STORAGE_CLASS_EXTERN;
5564         declaration->type                   = type;
5565         declaration->symbol                 = symbol;
5566         declaration->source_position        = *source_position;
5567
5568         bool strict_prototypes_old = warning.strict_prototypes;
5569         warning.strict_prototypes  = false;
5570         record_declaration(declaration);
5571         warning.strict_prototypes = strict_prototypes_old;
5572
5573         return declaration;
5574 }
5575
5576 /**
5577  * Creates a return_type (func)(argument_type) function type if not
5578  * already exists.
5579  */
5580 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
5581                                     type_t *argument_type2)
5582 {
5583         function_parameter_t *parameter2
5584                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
5585         memset(parameter2, 0, sizeof(parameter2[0]));
5586         parameter2->type = argument_type2;
5587
5588         function_parameter_t *parameter1
5589                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
5590         memset(parameter1, 0, sizeof(parameter1[0]));
5591         parameter1->type = argument_type1;
5592         parameter1->next = parameter2;
5593
5594         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5595         type->function.return_type = return_type;
5596         type->function.parameters  = parameter1;
5597
5598         type_t *result = typehash_insert(type);
5599         if (result != type) {
5600                 free_type(type);
5601         }
5602
5603         return result;
5604 }
5605
5606 /**
5607  * Creates a return_type (func)(argument_type) function type if not
5608  * already exists.
5609  *
5610  * @param return_type    the return type
5611  * @param argument_type  the argument type
5612  */
5613 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
5614 {
5615         function_parameter_t *parameter
5616                 = obstack_alloc(type_obst, sizeof(parameter[0]));
5617         memset(parameter, 0, sizeof(parameter[0]));
5618         parameter->type = argument_type;
5619
5620         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5621         type->function.return_type = return_type;
5622         type->function.parameters  = parameter;
5623
5624         type_t *result = typehash_insert(type);
5625         if (result != type) {
5626                 free_type(type);
5627         }
5628
5629         return result;
5630 }
5631
5632 static type_t *make_function_0_type(type_t *return_type)
5633 {
5634         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5635         type->function.return_type = return_type;
5636         type->function.parameters  = NULL;
5637
5638         type_t *result = typehash_insert(type);
5639         if (result != type) {
5640                 free_type(type);
5641         }
5642
5643         return result;
5644 }
5645
5646 /**
5647  * Creates a function type for some function like builtins.
5648  *
5649  * @param symbol   the symbol describing the builtin
5650  */
5651 static type_t *get_builtin_symbol_type(symbol_t *symbol)
5652 {
5653         switch(symbol->ID) {
5654         case T___builtin_alloca:
5655                 return make_function_1_type(type_void_ptr, type_size_t);
5656         case T___builtin_huge_val:
5657                 return make_function_0_type(type_double);
5658         case T___builtin_nan:
5659                 return make_function_1_type(type_double, type_char_ptr);
5660         case T___builtin_nanf:
5661                 return make_function_1_type(type_float, type_char_ptr);
5662         case T___builtin_nand:
5663                 return make_function_1_type(type_long_double, type_char_ptr);
5664         case T___builtin_va_end:
5665                 return make_function_1_type(type_void, type_valist);
5666         case T___builtin_expect:
5667                 return make_function_2_type(type_long, type_long, type_long);
5668         default:
5669                 internal_errorf(HERE, "not implemented builtin symbol found");
5670         }
5671 }
5672
5673 /**
5674  * Performs automatic type cast as described in § 6.3.2.1.
5675  *
5676  * @param orig_type  the original type
5677  */
5678 static type_t *automatic_type_conversion(type_t *orig_type)
5679 {
5680         type_t *type = skip_typeref(orig_type);
5681         if (is_type_array(type)) {
5682                 array_type_t *array_type   = &type->array;
5683                 type_t       *element_type = array_type->element_type;
5684                 unsigned      qualifiers   = array_type->base.qualifiers;
5685
5686                 return make_pointer_type(element_type, qualifiers);
5687         }
5688
5689         if (is_type_function(type)) {
5690                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
5691         }
5692
5693         return orig_type;
5694 }
5695
5696 /**
5697  * reverts the automatic casts of array to pointer types and function
5698  * to function-pointer types as defined § 6.3.2.1
5699  */
5700 type_t *revert_automatic_type_conversion(const expression_t *expression)
5701 {
5702         switch (expression->kind) {
5703                 case EXPR_REFERENCE: return expression->reference.declaration->type;
5704                 case EXPR_SELECT:    return expression->select.compound_entry->type;
5705
5706                 case EXPR_UNARY_DEREFERENCE: {
5707                         const expression_t *const value = expression->unary.value;
5708                         type_t             *const type  = skip_typeref(value->base.type);
5709                         assert(is_type_pointer(type));
5710                         return type->pointer.points_to;
5711                 }
5712
5713                 case EXPR_BUILTIN_SYMBOL:
5714                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
5715
5716                 case EXPR_ARRAY_ACCESS: {
5717                         const expression_t *array_ref = expression->array_access.array_ref;
5718                         type_t             *type_left = skip_typeref(array_ref->base.type);
5719                         if (!is_type_valid(type_left))
5720                                 return type_left;
5721                         assert(is_type_pointer(type_left));
5722                         return type_left->pointer.points_to;
5723                 }
5724
5725                 case EXPR_STRING_LITERAL: {
5726                         size_t size = expression->string.value.size;
5727                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
5728                 }
5729
5730                 case EXPR_WIDE_STRING_LITERAL: {
5731                         size_t size = expression->wide_string.value.size;
5732                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
5733                 }
5734
5735                 case EXPR_COMPOUND_LITERAL:
5736                         return expression->compound_literal.type;
5737
5738                 default: break;
5739         }
5740
5741         return expression->base.type;
5742 }
5743
5744 static expression_t *parse_reference(void)
5745 {
5746         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
5747
5748         reference_expression_t *ref = &expression->reference;
5749         symbol_t *const symbol = token.v.symbol;
5750
5751         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
5752
5753         source_position_t source_position = token.source_position;
5754         next_token();
5755
5756         if (declaration == NULL) {
5757                 if (! strict_mode && token.type == '(') {
5758                         /* an implicitly defined function */
5759                         if (warning.implicit_function_declaration) {
5760                                 warningf(HERE, "implicit declaration of function '%Y'",
5761                                         symbol);
5762                         }
5763
5764                         declaration = create_implicit_function(symbol,
5765                                                                &source_position);
5766                 } else {
5767                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
5768                         return create_invalid_expression();
5769                 }
5770         }
5771
5772         type_t *type         = declaration->type;
5773
5774         /* we always do the auto-type conversions; the & and sizeof parser contains
5775          * code to revert this! */
5776         type = automatic_type_conversion(type);
5777
5778         ref->declaration = declaration;
5779         ref->base.type   = type;
5780
5781         /* this declaration is used */
5782         declaration->used = true;
5783
5784         /* check for deprecated functions */
5785         if (warning.deprecated_declarations &&
5786             declaration->modifiers & DM_DEPRECATED) {
5787                 char const *const prefix = is_type_function(declaration->type) ?
5788                         "function" : "variable";
5789
5790                 if (declaration->deprecated_string != NULL) {
5791                         warningf(&source_position,
5792                                 "%s '%Y' is deprecated (declared %P): \"%s\"", prefix,
5793                                 declaration->symbol, &declaration->source_position,
5794                                 declaration->deprecated_string);
5795                 } else {
5796                         warningf(&source_position,
5797                                 "%s '%Y' is deprecated (declared %P)", prefix,
5798                                 declaration->symbol, &declaration->source_position);
5799                 }
5800         }
5801
5802         return expression;
5803 }
5804
5805 static void check_cast_allowed(expression_t *expression, type_t *dest_type)
5806 {
5807         (void) expression;
5808         (void) dest_type;
5809         /* TODO check if explicit cast is allowed and issue warnings/errors */
5810 }
5811
5812 static expression_t *parse_compound_literal(type_t *type)
5813 {
5814         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
5815
5816         parse_initializer_env_t env;
5817         env.type             = type;
5818         env.declaration      = NULL;
5819         env.must_be_constant = false;
5820         initializer_t *initializer = parse_initializer(&env);
5821         type = env.type;
5822
5823         expression->compound_literal.initializer = initializer;
5824         expression->compound_literal.type        = type;
5825         expression->base.type                    = automatic_type_conversion(type);
5826
5827         return expression;
5828 }
5829
5830 /**
5831  * Parse a cast expression.
5832  */
5833 static expression_t *parse_cast(void)
5834 {
5835         source_position_t source_position = token.source_position;
5836
5837         type_t *type  = parse_typename();
5838
5839         /* matching add_anchor_token() is at call site */
5840         rem_anchor_token(')');
5841         expect(')');
5842
5843         if (token.type == '{') {
5844                 return parse_compound_literal(type);
5845         }
5846
5847         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
5848         cast->base.source_position = source_position;
5849
5850         expression_t *value = parse_sub_expression(20);
5851
5852         check_cast_allowed(value, type);
5853
5854         cast->base.type   = type;
5855         cast->unary.value = value;
5856
5857         return cast;
5858 end_error:
5859         return create_invalid_expression();
5860 }
5861
5862 /**
5863  * Parse a statement expression.
5864  */
5865 static expression_t *parse_statement_expression(void)
5866 {
5867         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
5868
5869         statement_t *statement           = parse_compound_statement(true);
5870         expression->statement.statement  = statement;
5871         expression->base.source_position = statement->base.source_position;
5872
5873         /* find last statement and use its type */
5874         type_t *type = type_void;
5875         const statement_t *stmt = statement->compound.statements;
5876         if (stmt != NULL) {
5877                 while (stmt->base.next != NULL)
5878                         stmt = stmt->base.next;
5879
5880                 if (stmt->kind == STATEMENT_EXPRESSION) {
5881                         type = stmt->expression.expression->base.type;
5882                 }
5883         } else {
5884                 warningf(&expression->base.source_position, "empty statement expression ({})");
5885         }
5886         expression->base.type = type;
5887
5888         expect(')');
5889
5890         return expression;
5891 end_error:
5892         return create_invalid_expression();
5893 }
5894
5895 /**
5896  * Parse a braced expression.
5897  */
5898 static expression_t *parse_brace_expression(void)
5899 {
5900         eat('(');
5901         add_anchor_token(')');
5902
5903         switch(token.type) {
5904         case '{':
5905                 /* gcc extension: a statement expression */
5906                 return parse_statement_expression();
5907
5908         TYPE_QUALIFIERS
5909         TYPE_SPECIFIERS
5910                 return parse_cast();
5911         case T_IDENTIFIER:
5912                 if (is_typedef_symbol(token.v.symbol)) {
5913                         return parse_cast();
5914                 }
5915         }
5916
5917         expression_t *result = parse_expression();
5918         rem_anchor_token(')');
5919         expect(')');
5920
5921         return result;
5922 end_error:
5923         return create_invalid_expression();
5924 }
5925
5926 static expression_t *parse_function_keyword(void)
5927 {
5928         next_token();
5929         /* TODO */
5930
5931         if (current_function == NULL) {
5932                 errorf(HERE, "'__func__' used outside of a function");
5933         }
5934
5935         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5936         expression->base.type     = type_char_ptr;
5937         expression->funcname.kind = FUNCNAME_FUNCTION;
5938
5939         return expression;
5940 }
5941
5942 static expression_t *parse_pretty_function_keyword(void)
5943 {
5944         eat(T___PRETTY_FUNCTION__);
5945
5946         if (current_function == NULL) {
5947                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
5948         }
5949
5950         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5951         expression->base.type     = type_char_ptr;
5952         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
5953
5954         return expression;
5955 }
5956
5957 static expression_t *parse_funcsig_keyword(void)
5958 {
5959         eat(T___FUNCSIG__);
5960
5961         if (current_function == NULL) {
5962                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
5963         }
5964
5965         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5966         expression->base.type     = type_char_ptr;
5967         expression->funcname.kind = FUNCNAME_FUNCSIG;
5968
5969         return expression;
5970 }
5971
5972 static expression_t *parse_funcdname_keyword(void)
5973 {
5974         eat(T___FUNCDNAME__);
5975
5976         if (current_function == NULL) {
5977                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
5978         }
5979
5980         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5981         expression->base.type     = type_char_ptr;
5982         expression->funcname.kind = FUNCNAME_FUNCDNAME;
5983
5984         return expression;
5985 }
5986
5987 static designator_t *parse_designator(void)
5988 {
5989         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
5990         result->source_position = *HERE;
5991
5992         if (token.type != T_IDENTIFIER) {
5993                 parse_error_expected("while parsing member designator",
5994                                      T_IDENTIFIER, NULL);
5995                 return NULL;
5996         }
5997         result->symbol = token.v.symbol;
5998         next_token();
5999
6000         designator_t *last_designator = result;
6001         while(true) {
6002                 if (token.type == '.') {
6003                         next_token();
6004                         if (token.type != T_IDENTIFIER) {
6005                                 parse_error_expected("while parsing member designator",
6006                                                      T_IDENTIFIER, NULL);
6007                                 return NULL;
6008                         }
6009                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6010                         designator->source_position = *HERE;
6011                         designator->symbol          = token.v.symbol;
6012                         next_token();
6013
6014                         last_designator->next = designator;
6015                         last_designator       = designator;
6016                         continue;
6017                 }
6018                 if (token.type == '[') {
6019                         next_token();
6020                         add_anchor_token(']');
6021                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6022                         designator->source_position = *HERE;
6023                         designator->array_index     = parse_expression();
6024                         rem_anchor_token(']');
6025                         expect(']');
6026                         if (designator->array_index == NULL) {
6027                                 return NULL;
6028                         }
6029
6030                         last_designator->next = designator;
6031                         last_designator       = designator;
6032                         continue;
6033                 }
6034                 break;
6035         }
6036
6037         return result;
6038 end_error:
6039         return NULL;
6040 }
6041
6042 /**
6043  * Parse the __builtin_offsetof() expression.
6044  */
6045 static expression_t *parse_offsetof(void)
6046 {
6047         eat(T___builtin_offsetof);
6048
6049         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6050         expression->base.type    = type_size_t;
6051
6052         expect('(');
6053         add_anchor_token(',');
6054         type_t *type = parse_typename();
6055         rem_anchor_token(',');
6056         expect(',');
6057         add_anchor_token(')');
6058         designator_t *designator = parse_designator();
6059         rem_anchor_token(')');
6060         expect(')');
6061
6062         expression->offsetofe.type       = type;
6063         expression->offsetofe.designator = designator;
6064
6065         type_path_t path;
6066         memset(&path, 0, sizeof(path));
6067         path.top_type = type;
6068         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6069
6070         descend_into_subtype(&path);
6071
6072         if (!walk_designator(&path, designator, true)) {
6073                 return create_invalid_expression();
6074         }
6075
6076         DEL_ARR_F(path.path);
6077
6078         return expression;
6079 end_error:
6080         return create_invalid_expression();
6081 }
6082
6083 /**
6084  * Parses a _builtin_va_start() expression.
6085  */
6086 static expression_t *parse_va_start(void)
6087 {
6088         eat(T___builtin_va_start);
6089
6090         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6091
6092         expect('(');
6093         add_anchor_token(',');
6094         expression->va_starte.ap = parse_assignment_expression();
6095         rem_anchor_token(',');
6096         expect(',');
6097         expression_t *const expr = parse_assignment_expression();
6098         if (expr->kind == EXPR_REFERENCE) {
6099                 declaration_t *const decl = expr->reference.declaration;
6100                 if (decl == NULL)
6101                         return create_invalid_expression();
6102                 if (decl->parent_scope == &current_function->scope &&
6103                     decl->next == NULL) {
6104                         expression->va_starte.parameter = decl;
6105                         expect(')');
6106                         return expression;
6107                 }
6108         }
6109         errorf(&expr->base.source_position,
6110                "second argument of 'va_start' must be last parameter of the current function");
6111 end_error:
6112         return create_invalid_expression();
6113 }
6114
6115 /**
6116  * Parses a _builtin_va_arg() expression.
6117  */
6118 static expression_t *parse_va_arg(void)
6119 {
6120         eat(T___builtin_va_arg);
6121
6122         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6123
6124         expect('(');
6125         expression->va_arge.ap = parse_assignment_expression();
6126         expect(',');
6127         expression->base.type = parse_typename();
6128         expect(')');
6129
6130         return expression;
6131 end_error:
6132         return create_invalid_expression();
6133 }
6134
6135 static expression_t *parse_builtin_symbol(void)
6136 {
6137         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
6138
6139         symbol_t *symbol = token.v.symbol;
6140
6141         expression->builtin_symbol.symbol = symbol;
6142         next_token();
6143
6144         type_t *type = get_builtin_symbol_type(symbol);
6145         type = automatic_type_conversion(type);
6146
6147         expression->base.type = type;
6148         return expression;
6149 }
6150
6151 /**
6152  * Parses a __builtin_constant() expression.
6153  */
6154 static expression_t *parse_builtin_constant(void)
6155 {
6156         eat(T___builtin_constant_p);
6157
6158         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6159
6160         expect('(');
6161         add_anchor_token(')');
6162         expression->builtin_constant.value = parse_assignment_expression();
6163         rem_anchor_token(')');
6164         expect(')');
6165         expression->base.type = type_int;
6166
6167         return expression;
6168 end_error:
6169         return create_invalid_expression();
6170 }
6171
6172 /**
6173  * Parses a __builtin_prefetch() expression.
6174  */
6175 static expression_t *parse_builtin_prefetch(void)
6176 {
6177         eat(T___builtin_prefetch);
6178
6179         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
6180
6181         expect('(');
6182         add_anchor_token(')');
6183         expression->builtin_prefetch.adr = parse_assignment_expression();
6184         if (token.type == ',') {
6185                 next_token();
6186                 expression->builtin_prefetch.rw = parse_assignment_expression();
6187         }
6188         if (token.type == ',') {
6189                 next_token();
6190                 expression->builtin_prefetch.locality = parse_assignment_expression();
6191         }
6192         rem_anchor_token(')');
6193         expect(')');
6194         expression->base.type = type_void;
6195
6196         return expression;
6197 end_error:
6198         return create_invalid_expression();
6199 }
6200
6201 /**
6202  * Parses a __builtin_is_*() compare expression.
6203  */
6204 static expression_t *parse_compare_builtin(void)
6205 {
6206         expression_t *expression;
6207
6208         switch(token.type) {
6209         case T___builtin_isgreater:
6210                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6211                 break;
6212         case T___builtin_isgreaterequal:
6213                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6214                 break;
6215         case T___builtin_isless:
6216                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6217                 break;
6218         case T___builtin_islessequal:
6219                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6220                 break;
6221         case T___builtin_islessgreater:
6222                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6223                 break;
6224         case T___builtin_isunordered:
6225                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6226                 break;
6227         default:
6228                 internal_errorf(HERE, "invalid compare builtin found");
6229                 break;
6230         }
6231         expression->base.source_position = *HERE;
6232         next_token();
6233
6234         expect('(');
6235         expression->binary.left = parse_assignment_expression();
6236         expect(',');
6237         expression->binary.right = parse_assignment_expression();
6238         expect(')');
6239
6240         type_t *const orig_type_left  = expression->binary.left->base.type;
6241         type_t *const orig_type_right = expression->binary.right->base.type;
6242
6243         type_t *const type_left  = skip_typeref(orig_type_left);
6244         type_t *const type_right = skip_typeref(orig_type_right);
6245         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6246                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6247                         type_error_incompatible("invalid operands in comparison",
6248                                 &expression->base.source_position, orig_type_left, orig_type_right);
6249                 }
6250         } else {
6251                 semantic_comparison(&expression->binary);
6252         }
6253
6254         return expression;
6255 end_error:
6256         return create_invalid_expression();
6257 }
6258
6259 #if 0
6260 /**
6261  * Parses a __builtin_expect() expression.
6262  */
6263 static expression_t *parse_builtin_expect(void)
6264 {
6265         eat(T___builtin_expect);
6266
6267         expression_t *expression
6268                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
6269
6270         expect('(');
6271         expression->binary.left = parse_assignment_expression();
6272         expect(',');
6273         expression->binary.right = parse_constant_expression();
6274         expect(')');
6275
6276         expression->base.type = expression->binary.left->base.type;
6277
6278         return expression;
6279 end_error:
6280         return create_invalid_expression();
6281 }
6282 #endif
6283
6284 /**
6285  * Parses a MS assume() expression.
6286  */
6287 static expression_t *parse_assume(void)
6288 {
6289         eat(T__assume);
6290
6291         expression_t *expression
6292                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
6293
6294         expect('(');
6295         add_anchor_token(')');
6296         expression->unary.value = parse_assignment_expression();
6297         rem_anchor_token(')');
6298         expect(')');
6299
6300         expression->base.type = type_void;
6301         return expression;
6302 end_error:
6303         return create_invalid_expression();
6304 }
6305
6306 /**
6307  * Parse a microsoft __noop expression.
6308  */
6309 static expression_t *parse_noop_expression(void)
6310 {
6311         source_position_t source_position = *HERE;
6312         eat(T___noop);
6313
6314         if (token.type == '(') {
6315                 /* parse arguments */
6316                 eat('(');
6317                 add_anchor_token(')');
6318                 add_anchor_token(',');
6319
6320                 if (token.type != ')') {
6321                         while(true) {
6322                                 (void)parse_assignment_expression();
6323                                 if (token.type != ',')
6324                                         break;
6325                                 next_token();
6326                         }
6327                 }
6328         }
6329         rem_anchor_token(',');
6330         rem_anchor_token(')');
6331         expect(')');
6332
6333         /* the result is a (int)0 */
6334         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6335         cnst->base.source_position = source_position;
6336         cnst->base.type            = type_int;
6337         cnst->conste.v.int_value   = 0;
6338         cnst->conste.is_ms_noop    = true;
6339
6340         return cnst;
6341
6342 end_error:
6343         return create_invalid_expression();
6344 }
6345
6346 /**
6347  * Parses a primary expression.
6348  */
6349 static expression_t *parse_primary_expression(void)
6350 {
6351         switch (token.type) {
6352                 case T_INTEGER:                  return parse_int_const();
6353                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
6354                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
6355                 case T_FLOATINGPOINT:            return parse_float_const();
6356                 case T_STRING_LITERAL:
6357                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
6358                 case T_IDENTIFIER:               return parse_reference();
6359                 case T___FUNCTION__:
6360                 case T___func__:                 return parse_function_keyword();
6361                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
6362                 case T___FUNCSIG__:              return parse_funcsig_keyword();
6363                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
6364                 case T___builtin_offsetof:       return parse_offsetof();
6365                 case T___builtin_va_start:       return parse_va_start();
6366                 case T___builtin_va_arg:         return parse_va_arg();
6367                 case T___builtin_expect:
6368                 case T___builtin_alloca:
6369                 case T___builtin_nan:
6370                 case T___builtin_nand:
6371                 case T___builtin_nanf:
6372                 case T___builtin_huge_val:
6373                 case T___builtin_va_end:         return parse_builtin_symbol();
6374                 case T___builtin_isgreater:
6375                 case T___builtin_isgreaterequal:
6376                 case T___builtin_isless:
6377                 case T___builtin_islessequal:
6378                 case T___builtin_islessgreater:
6379                 case T___builtin_isunordered:    return parse_compare_builtin();
6380                 case T___builtin_constant_p:     return parse_builtin_constant();
6381                 case T___builtin_prefetch:       return parse_builtin_prefetch();
6382                 case T__assume:                  return parse_assume();
6383
6384                 case '(':                        return parse_brace_expression();
6385                 case T___noop:                   return parse_noop_expression();
6386         }
6387
6388         errorf(HERE, "unexpected token %K, expected an expression", &token);
6389         return create_invalid_expression();
6390 }
6391
6392 /**
6393  * Check if the expression has the character type and issue a warning then.
6394  */
6395 static void check_for_char_index_type(const expression_t *expression)
6396 {
6397         type_t       *const type      = expression->base.type;
6398         const type_t *const base_type = skip_typeref(type);
6399
6400         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
6401                         warning.char_subscripts) {
6402                 warningf(&expression->base.source_position,
6403                          "array subscript has type '%T'", type);
6404         }
6405 }
6406
6407 static expression_t *parse_array_expression(unsigned precedence,
6408                                             expression_t *left)
6409 {
6410         (void) precedence;
6411
6412         eat('[');
6413         add_anchor_token(']');
6414
6415         expression_t *inside = parse_expression();
6416
6417         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
6418
6419         array_access_expression_t *array_access = &expression->array_access;
6420
6421         type_t *const orig_type_left   = left->base.type;
6422         type_t *const orig_type_inside = inside->base.type;
6423
6424         type_t *const type_left   = skip_typeref(orig_type_left);
6425         type_t *const type_inside = skip_typeref(orig_type_inside);
6426
6427         type_t *return_type;
6428         if (is_type_pointer(type_left)) {
6429                 return_type             = type_left->pointer.points_to;
6430                 array_access->array_ref = left;
6431                 array_access->index     = inside;
6432                 check_for_char_index_type(inside);
6433         } else if (is_type_pointer(type_inside)) {
6434                 return_type             = type_inside->pointer.points_to;
6435                 array_access->array_ref = inside;
6436                 array_access->index     = left;
6437                 array_access->flipped   = true;
6438                 check_for_char_index_type(left);
6439         } else {
6440                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
6441                         errorf(HERE,
6442                                 "array access on object with non-pointer types '%T', '%T'",
6443                                 orig_type_left, orig_type_inside);
6444                 }
6445                 return_type             = type_error_type;
6446                 array_access->array_ref = create_invalid_expression();
6447         }
6448
6449         rem_anchor_token(']');
6450         if (token.type != ']') {
6451                 parse_error_expected("Problem while parsing array access", ']', NULL);
6452                 return expression;
6453         }
6454         next_token();
6455
6456         return_type           = automatic_type_conversion(return_type);
6457         expression->base.type = return_type;
6458
6459         return expression;
6460 }
6461
6462 static expression_t *parse_typeprop(expression_kind_t const kind,
6463                                     source_position_t const pos,
6464                                     unsigned const precedence)
6465 {
6466         expression_t *tp_expression = allocate_expression_zero(kind);
6467         tp_expression->base.type            = type_size_t;
6468         tp_expression->base.source_position = pos;
6469
6470         char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
6471
6472         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
6473                 next_token();
6474                 add_anchor_token(')');
6475                 type_t* const orig_type = parse_typename();
6476                 tp_expression->typeprop.type = orig_type;
6477
6478                 type_t const* const type = skip_typeref(orig_type);
6479                 char const* const wrong_type =
6480                         is_type_incomplete(type)    ? "incomplete"          :
6481                         type->kind == TYPE_FUNCTION ? "function designator" :
6482                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6483                         NULL;
6484                 if (wrong_type != NULL) {
6485                         errorf(&pos, "operand of %s expression must not be %s type '%T'",
6486                                what, wrong_type, type);
6487                 }
6488
6489                 rem_anchor_token(')');
6490                 expect(')');
6491         } else {
6492                 expression_t *expression = parse_sub_expression(precedence);
6493
6494                 type_t* const orig_type = revert_automatic_type_conversion(expression);
6495                 expression->base.type = orig_type;
6496
6497                 type_t const* const type = skip_typeref(orig_type);
6498                 char const* const wrong_type =
6499                         is_type_incomplete(type)    ? "incomplete"          :
6500                         type->kind == TYPE_FUNCTION ? "function designator" :
6501                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6502                         NULL;
6503                 if (wrong_type != NULL) {
6504                         errorf(&pos, "operand of %s expression must not be expression of %s type '%T'", what, wrong_type, type);
6505                 }
6506
6507                 tp_expression->typeprop.type          = expression->base.type;
6508                 tp_expression->typeprop.tp_expression = expression;
6509         }
6510
6511         return tp_expression;
6512 end_error:
6513         return create_invalid_expression();
6514 }
6515
6516 static expression_t *parse_sizeof(unsigned precedence)
6517 {
6518         source_position_t pos = *HERE;
6519         eat(T_sizeof);
6520         return parse_typeprop(EXPR_SIZEOF, pos, precedence);
6521 }
6522
6523 static expression_t *parse_alignof(unsigned precedence)
6524 {
6525         source_position_t pos = *HERE;
6526         eat(T___alignof__);
6527         return parse_typeprop(EXPR_ALIGNOF, pos, precedence);
6528 }
6529
6530 static expression_t *parse_select_expression(unsigned precedence,
6531                                              expression_t *compound)
6532 {
6533         (void) precedence;
6534         assert(token.type == '.' || token.type == T_MINUSGREATER);
6535
6536         bool is_pointer = (token.type == T_MINUSGREATER);
6537         next_token();
6538
6539         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
6540         select->select.compound = compound;
6541
6542         if (token.type != T_IDENTIFIER) {
6543                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
6544                 return select;
6545         }
6546         symbol_t *symbol      = token.v.symbol;
6547         select->select.symbol = symbol;
6548         next_token();
6549
6550         type_t *const orig_type = compound->base.type;
6551         type_t *const type      = skip_typeref(orig_type);
6552
6553         type_t *type_left = type;
6554         if (is_pointer) {
6555                 if (!is_type_pointer(type)) {
6556                         if (is_type_valid(type)) {
6557                                 errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
6558                         }
6559                         return create_invalid_expression();
6560                 }
6561                 type_left = type->pointer.points_to;
6562         }
6563         type_left = skip_typeref(type_left);
6564
6565         if (type_left->kind != TYPE_COMPOUND_STRUCT &&
6566             type_left->kind != TYPE_COMPOUND_UNION) {
6567                 if (is_type_valid(type_left)) {
6568                         errorf(HERE, "request for member '%Y' in something not a struct or "
6569                                "union, but '%T'", symbol, type_left);
6570                 }
6571                 return create_invalid_expression();
6572         }
6573
6574         declaration_t *const declaration = type_left->compound.declaration;
6575
6576         if (!declaration->init.complete) {
6577                 errorf(HERE, "request for member '%Y' of incomplete type '%T'",
6578                        symbol, type_left);
6579                 return create_invalid_expression();
6580         }
6581
6582         declaration_t *iter = find_compound_entry(declaration, symbol);
6583         if (iter == NULL) {
6584                 errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
6585                 return create_invalid_expression();
6586         }
6587
6588         /* we always do the auto-type conversions; the & and sizeof parser contains
6589          * code to revert this! */
6590         type_t *expression_type = automatic_type_conversion(iter->type);
6591
6592         select->select.compound_entry = iter;
6593         select->base.type             = expression_type;
6594
6595         type_t *skipped = skip_typeref(iter->type);
6596         if (skipped->kind == TYPE_BITFIELD) {
6597                 select->base.type = skipped->bitfield.base_type;
6598         }
6599
6600         return select;
6601 }
6602
6603 static void check_call_argument(const function_parameter_t *parameter,
6604                                 call_argument_t *argument)
6605 {
6606         type_t         *expected_type      = parameter->type;
6607         type_t         *expected_type_skip = skip_typeref(expected_type);
6608         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
6609         expression_t   *arg_expr           = argument->expression;
6610
6611         /* handle transparent union gnu extension */
6612         if (is_type_union(expected_type_skip)
6613                         && (expected_type_skip->base.modifiers
6614                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
6615                 declaration_t  *union_decl = expected_type_skip->compound.declaration;
6616
6617                 declaration_t *declaration = union_decl->scope.declarations;
6618                 type_t        *best_type   = NULL;
6619                 for ( ; declaration != NULL; declaration = declaration->next) {
6620                         type_t *decl_type = declaration->type;
6621                         error = semantic_assign(decl_type, arg_expr);
6622                         if (error == ASSIGN_ERROR_INCOMPATIBLE
6623                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
6624                                 continue;
6625
6626                         if (error == ASSIGN_SUCCESS) {
6627                                 best_type = decl_type;
6628                         } else if (best_type == NULL) {
6629                                 best_type = decl_type;
6630                         }
6631                 }
6632
6633                 if (best_type != NULL) {
6634                         expected_type = best_type;
6635                 }
6636         }
6637
6638         error                = semantic_assign(expected_type, arg_expr);
6639         argument->expression = create_implicit_cast(argument->expression,
6640                                                     expected_type);
6641
6642         /* TODO report exact scope in error messages (like "in 3rd parameter") */
6643         report_assign_error(error, expected_type, arg_expr,     "function call",
6644                             &arg_expr->base.source_position);
6645 }
6646
6647 /**
6648  * Parse a call expression, ie. expression '( ... )'.
6649  *
6650  * @param expression  the function address
6651  */
6652 static expression_t *parse_call_expression(unsigned precedence,
6653                                            expression_t *expression)
6654 {
6655         (void) precedence;
6656         expression_t *result = allocate_expression_zero(EXPR_CALL);
6657         result->base.source_position = expression->base.source_position;
6658
6659         call_expression_t *call = &result->call;
6660         call->function          = expression;
6661
6662         type_t *const orig_type = expression->base.type;
6663         type_t *const type      = skip_typeref(orig_type);
6664
6665         function_type_t *function_type = NULL;
6666         if (is_type_pointer(type)) {
6667                 type_t *const to_type = skip_typeref(type->pointer.points_to);
6668
6669                 if (is_type_function(to_type)) {
6670                         function_type   = &to_type->function;
6671                         call->base.type = function_type->return_type;
6672                 }
6673         }
6674
6675         if (function_type == NULL && is_type_valid(type)) {
6676                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
6677         }
6678
6679         /* parse arguments */
6680         eat('(');
6681         add_anchor_token(')');
6682         add_anchor_token(',');
6683
6684         if (token.type != ')') {
6685                 call_argument_t *last_argument = NULL;
6686
6687                 while(true) {
6688                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
6689
6690                         argument->expression = parse_assignment_expression();
6691                         if (last_argument == NULL) {
6692                                 call->arguments = argument;
6693                         } else {
6694                                 last_argument->next = argument;
6695                         }
6696                         last_argument = argument;
6697
6698                         if (token.type != ',')
6699                                 break;
6700                         next_token();
6701                 }
6702         }
6703         rem_anchor_token(',');
6704         rem_anchor_token(')');
6705         expect(')');
6706
6707         if (function_type == NULL)
6708                 return result;
6709
6710         function_parameter_t *parameter = function_type->parameters;
6711         call_argument_t      *argument  = call->arguments;
6712         if (!function_type->unspecified_parameters) {
6713                 for( ; parameter != NULL && argument != NULL;
6714                                 parameter = parameter->next, argument = argument->next) {
6715                         check_call_argument(parameter, argument);
6716                 }
6717
6718                 if (parameter != NULL) {
6719                         errorf(HERE, "too few arguments to function '%E'", expression);
6720                 } else if (argument != NULL && !function_type->variadic) {
6721                         errorf(HERE, "too many arguments to function '%E'", expression);
6722                 }
6723         }
6724
6725         /* do default promotion */
6726         for( ; argument != NULL; argument = argument->next) {
6727                 type_t *type = argument->expression->base.type;
6728
6729                 type = get_default_promoted_type(type);
6730
6731                 argument->expression
6732                         = create_implicit_cast(argument->expression, type);
6733         }
6734
6735         check_format(&result->call);
6736
6737         return result;
6738 end_error:
6739         return create_invalid_expression();
6740 }
6741
6742 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
6743
6744 static bool same_compound_type(const type_t *type1, const type_t *type2)
6745 {
6746         return
6747                 is_type_compound(type1) &&
6748                 type1->kind == type2->kind &&
6749                 type1->compound.declaration == type2->compound.declaration;
6750 }
6751
6752 /**
6753  * Parse a conditional expression, ie. 'expression ? ... : ...'.
6754  *
6755  * @param expression  the conditional expression
6756  */
6757 static expression_t *parse_conditional_expression(unsigned precedence,
6758                                                   expression_t *expression)
6759 {
6760         eat('?');
6761         add_anchor_token(':');
6762
6763         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
6764
6765         conditional_expression_t *conditional = &result->conditional;
6766         conditional->condition = expression;
6767
6768         /* 6.5.15.2 */
6769         type_t *const condition_type_orig = expression->base.type;
6770         type_t *const condition_type      = skip_typeref(condition_type_orig);
6771         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
6772                 type_error("expected a scalar type in conditional condition",
6773                            &expression->base.source_position, condition_type_orig);
6774         }
6775
6776         expression_t *true_expression = parse_expression();
6777         rem_anchor_token(':');
6778         expect(':');
6779         expression_t *false_expression = parse_sub_expression(precedence);
6780
6781         type_t *const orig_true_type  = true_expression->base.type;
6782         type_t *const orig_false_type = false_expression->base.type;
6783         type_t *const true_type       = skip_typeref(orig_true_type);
6784         type_t *const false_type      = skip_typeref(orig_false_type);
6785
6786         /* 6.5.15.3 */
6787         type_t *result_type;
6788         if (is_type_atomic(true_type, ATOMIC_TYPE_VOID) ||
6789                 is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
6790                 if (!is_type_atomic(true_type, ATOMIC_TYPE_VOID)
6791                     || !is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
6792                         warningf(&expression->base.source_position,
6793                                         "ISO C forbids conditional expression with only one void side");
6794                 }
6795                 result_type = type_void;
6796         } else if (is_type_arithmetic(true_type)
6797                    && is_type_arithmetic(false_type)) {
6798                 result_type = semantic_arithmetic(true_type, false_type);
6799
6800                 true_expression  = create_implicit_cast(true_expression, result_type);
6801                 false_expression = create_implicit_cast(false_expression, result_type);
6802
6803                 conditional->true_expression  = true_expression;
6804                 conditional->false_expression = false_expression;
6805                 conditional->base.type        = result_type;
6806         } else if (same_compound_type(true_type, false_type)) {
6807                 /* just take 1 of the 2 types */
6808                 result_type = true_type;
6809         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
6810                 type_t *pointer_type;
6811                 type_t *other_type;
6812                 expression_t *other_expression;
6813                 if (is_type_pointer(true_type) &&
6814                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
6815                         pointer_type     = true_type;
6816                         other_type       = false_type;
6817                         other_expression = false_expression;
6818                 } else {
6819                         pointer_type     = false_type;
6820                         other_type       = true_type;
6821                         other_expression = true_expression;
6822                 }
6823
6824                 if (is_null_pointer_constant(other_expression)) {
6825                         result_type = pointer_type;
6826                 } else if (is_type_pointer(other_type)) {
6827                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
6828                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
6829
6830                         type_t *to;
6831                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
6832                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
6833                                 to = type_void;
6834                         } else if (types_compatible(get_unqualified_type(to1),
6835                                                     get_unqualified_type(to2))) {
6836                                 to = to1;
6837                         } else {
6838                                 warningf(&expression->base.source_position,
6839                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
6840                                         true_type, false_type);
6841                                 to = type_void;
6842                         }
6843
6844                         type_t *const copy = duplicate_type(to);
6845                         copy->base.qualifiers = to1->base.qualifiers | to2->base.qualifiers;
6846
6847                         type_t *const type = typehash_insert(copy);
6848                         if (type != copy)
6849                                 free_type(copy);
6850
6851                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
6852                 } else if (is_type_integer(other_type)) {
6853                         warningf(&expression->base.source_position,
6854                                         "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
6855                         result_type = pointer_type;
6856                 } else {
6857                         type_error_incompatible("while parsing conditional",
6858                                         &expression->base.source_position, true_type, false_type);
6859                         result_type = type_error_type;
6860                 }
6861         } else {
6862                 /* TODO: one pointer to void*, other some pointer */
6863
6864                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
6865                         type_error_incompatible("while parsing conditional",
6866                                                 &expression->base.source_position, true_type,
6867                                                 false_type);
6868                 }
6869                 result_type = type_error_type;
6870         }
6871
6872         conditional->true_expression
6873                 = create_implicit_cast(true_expression, result_type);
6874         conditional->false_expression
6875                 = create_implicit_cast(false_expression, result_type);
6876         conditional->base.type = result_type;
6877         return result;
6878 end_error:
6879         return create_invalid_expression();
6880 }
6881
6882 /**
6883  * Parse an extension expression.
6884  */
6885 static expression_t *parse_extension(unsigned precedence)
6886 {
6887         eat(T___extension__);
6888
6889         /* TODO enable extensions */
6890         expression_t *expression = parse_sub_expression(precedence);
6891         /* TODO disable extensions */
6892         return expression;
6893 }
6894
6895 /**
6896  * Parse a __builtin_classify_type() expression.
6897  */
6898 static expression_t *parse_builtin_classify_type(const unsigned precedence)
6899 {
6900         eat(T___builtin_classify_type);
6901
6902         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
6903         result->base.type    = type_int;
6904
6905         expect('(');
6906         add_anchor_token(')');
6907         expression_t *expression = parse_sub_expression(precedence);
6908         rem_anchor_token(')');
6909         expect(')');
6910         result->classify_type.type_expression = expression;
6911
6912         return result;
6913 end_error:
6914         return create_invalid_expression();
6915 }
6916
6917 static void check_pointer_arithmetic(const source_position_t *source_position,
6918                                      type_t *pointer_type,
6919                                      type_t *orig_pointer_type)
6920 {
6921         type_t *points_to = pointer_type->pointer.points_to;
6922         points_to = skip_typeref(points_to);
6923
6924         if (is_type_incomplete(points_to) &&
6925                         (! (c_mode & _GNUC)
6926                          || !is_type_atomic(points_to, ATOMIC_TYPE_VOID))) {
6927                 errorf(source_position,
6928                            "arithmetic with pointer to incomplete type '%T' not allowed",
6929                            orig_pointer_type);
6930         } else if (is_type_function(points_to)) {
6931                 errorf(source_position,
6932                            "arithmetic with pointer to function type '%T' not allowed",
6933                            orig_pointer_type);
6934         }
6935 }
6936
6937 static void semantic_incdec(unary_expression_t *expression)
6938 {
6939         type_t *const orig_type = expression->value->base.type;
6940         type_t *const type      = skip_typeref(orig_type);
6941         if (is_type_pointer(type)) {
6942                 check_pointer_arithmetic(&expression->base.source_position,
6943                                          type, orig_type);
6944         } else if (!is_type_real(type) && is_type_valid(type)) {
6945                 /* TODO: improve error message */
6946                 errorf(HERE, "operation needs an arithmetic or pointer type");
6947         }
6948         expression->base.type = orig_type;
6949 }
6950
6951 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
6952 {
6953         type_t *const orig_type = expression->value->base.type;
6954         type_t *const type      = skip_typeref(orig_type);
6955         if (!is_type_arithmetic(type)) {
6956                 if (is_type_valid(type)) {
6957                         /* TODO: improve error message */
6958                         errorf(HERE, "operation needs an arithmetic type");
6959                 }
6960                 return;
6961         }
6962
6963         expression->base.type = orig_type;
6964 }
6965
6966 static void semantic_unexpr_scalar(unary_expression_t *expression)
6967 {
6968         type_t *const orig_type = expression->value->base.type;
6969         type_t *const type      = skip_typeref(orig_type);
6970         if (!is_type_scalar(type)) {
6971                 if (is_type_valid(type)) {
6972                         errorf(HERE, "operand of ! must be of scalar type");
6973                 }
6974                 return;
6975         }
6976
6977         expression->base.type = orig_type;
6978 }
6979
6980 static void semantic_unexpr_integer(unary_expression_t *expression)
6981 {
6982         type_t *const orig_type = expression->value->base.type;
6983         type_t *const type      = skip_typeref(orig_type);
6984         if (!is_type_integer(type)) {
6985                 if (is_type_valid(type)) {
6986                         errorf(HERE, "operand of ~ must be of integer type");
6987                 }
6988                 return;
6989         }
6990
6991         expression->base.type = orig_type;
6992 }
6993
6994 static void semantic_dereference(unary_expression_t *expression)
6995 {
6996         type_t *const orig_type = expression->value->base.type;
6997         type_t *const type      = skip_typeref(orig_type);
6998         if (!is_type_pointer(type)) {
6999                 if (is_type_valid(type)) {
7000                         errorf(HERE, "Unary '*' needs pointer or arrray type, but type '%T' given", orig_type);
7001                 }
7002                 return;
7003         }
7004
7005         type_t *result_type   = type->pointer.points_to;
7006         result_type           = automatic_type_conversion(result_type);
7007         expression->base.type = result_type;
7008 }
7009
7010 static void set_address_taken(expression_t *expression, bool may_be_register)
7011 {
7012         if (expression->kind != EXPR_REFERENCE)
7013                 return;
7014
7015         declaration_t *const declaration = expression->reference.declaration;
7016         /* happens for parse errors */
7017         if (declaration == NULL)
7018                 return;
7019
7020         if (declaration->storage_class == STORAGE_CLASS_REGISTER && !may_be_register) {
7021                 errorf(&expression->base.source_position,
7022                                 "address of register variable '%Y' requested",
7023                                 declaration->symbol);
7024         } else {
7025                 declaration->address_taken = 1;
7026         }
7027 }
7028
7029 /**
7030  * Check the semantic of the address taken expression.
7031  */
7032 static void semantic_take_addr(unary_expression_t *expression)
7033 {
7034         expression_t *value = expression->value;
7035         value->base.type    = revert_automatic_type_conversion(value);
7036
7037         type_t *orig_type = value->base.type;
7038         if (!is_type_valid(orig_type))
7039                 return;
7040
7041         set_address_taken(value, false);
7042
7043         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
7044 }
7045
7046 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc)   \
7047 static expression_t *parse_##unexpression_type(unsigned precedence)            \
7048 {                                                                              \
7049         eat(token_type);                                                           \
7050                                                                                    \
7051         expression_t *unary_expression                                             \
7052                 = allocate_expression_zero(unexpression_type);                         \
7053         unary_expression->base.source_position = *HERE;                            \
7054         unary_expression->unary.value = parse_sub_expression(precedence);          \
7055                                                                                    \
7056         sfunc(&unary_expression->unary);                                           \
7057                                                                                    \
7058         return unary_expression;                                                   \
7059 }
7060
7061 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
7062                                semantic_unexpr_arithmetic)
7063 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
7064                                semantic_unexpr_arithmetic)
7065 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
7066                                semantic_unexpr_scalar)
7067 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
7068                                semantic_dereference)
7069 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
7070                                semantic_take_addr)
7071 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
7072                                semantic_unexpr_integer)
7073 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
7074                                semantic_incdec)
7075 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
7076                                semantic_incdec)
7077
7078 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
7079                                                sfunc)                         \
7080 static expression_t *parse_##unexpression_type(unsigned precedence,           \
7081                                                expression_t *left)            \
7082 {                                                                             \
7083         (void) precedence;                                                        \
7084         eat(token_type);                                                          \
7085                                                                               \
7086         expression_t *unary_expression                                            \
7087                 = allocate_expression_zero(unexpression_type);                        \
7088         unary_expression->unary.value = left;                                     \
7089                                                                                   \
7090         sfunc(&unary_expression->unary);                                          \
7091                                                                               \
7092         return unary_expression;                                                  \
7093 }
7094
7095 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
7096                                        EXPR_UNARY_POSTFIX_INCREMENT,
7097                                        semantic_incdec)
7098 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
7099                                        EXPR_UNARY_POSTFIX_DECREMENT,
7100                                        semantic_incdec)
7101
7102 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
7103 {
7104         /* TODO: handle complex + imaginary types */
7105
7106         /* § 6.3.1.8 Usual arithmetic conversions */
7107         if (type_left == type_long_double || type_right == type_long_double) {
7108                 return type_long_double;
7109         } else if (type_left == type_double || type_right == type_double) {
7110                 return type_double;
7111         } else if (type_left == type_float || type_right == type_float) {
7112                 return type_float;
7113         }
7114
7115         type_left  = promote_integer(type_left);
7116         type_right = promote_integer(type_right);
7117
7118         if (type_left == type_right)
7119                 return type_left;
7120
7121         bool const signed_left  = is_type_signed(type_left);
7122         bool const signed_right = is_type_signed(type_right);
7123         int  const rank_left    = get_rank(type_left);
7124         int  const rank_right   = get_rank(type_right);
7125
7126         if (signed_left == signed_right)
7127                 return rank_left >= rank_right ? type_left : type_right;
7128
7129         int     s_rank;
7130         int     u_rank;
7131         type_t *s_type;
7132         type_t *u_type;
7133         if (signed_left) {
7134                 s_rank = rank_left;
7135                 s_type = type_left;
7136                 u_rank = rank_right;
7137                 u_type = type_right;
7138         } else {
7139                 s_rank = rank_right;
7140                 s_type = type_right;
7141                 u_rank = rank_left;
7142                 u_type = type_left;
7143         }
7144
7145         if (u_rank >= s_rank)
7146                 return u_type;
7147
7148         if (get_atomic_type_size(s_rank) > get_atomic_type_size(u_rank))
7149                 return s_type;
7150
7151         /* FIXME ugly */
7152         type_t *const type = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
7153         switch (s_rank) {
7154                 case ATOMIC_TYPE_INT:      type->atomic.akind = ATOMIC_TYPE_UINT;      break;
7155                 case ATOMIC_TYPE_LONG:     type->atomic.akind = ATOMIC_TYPE_ULONG;     break;
7156                 case ATOMIC_TYPE_LONGLONG: type->atomic.akind = ATOMIC_TYPE_ULONGLONG; break;
7157
7158                 default: panic("invalid atomic type");
7159         }
7160
7161         type_t* const result = typehash_insert(type);
7162         if (result != type)
7163                 free_type(type);
7164
7165         return result;
7166 }
7167
7168 /**
7169  * Check the semantic restrictions for a binary expression.
7170  */
7171 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
7172 {
7173         expression_t *const left            = expression->left;
7174         expression_t *const right           = expression->right;
7175         type_t       *const orig_type_left  = left->base.type;
7176         type_t       *const orig_type_right = right->base.type;
7177         type_t       *const type_left       = skip_typeref(orig_type_left);
7178         type_t       *const type_right      = skip_typeref(orig_type_right);
7179
7180         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7181                 /* TODO: improve error message */
7182                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7183                         errorf(HERE, "operation needs arithmetic types");
7184                 }
7185                 return;
7186         }
7187
7188         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7189         expression->left      = create_implicit_cast(left, arithmetic_type);
7190         expression->right     = create_implicit_cast(right, arithmetic_type);
7191         expression->base.type = arithmetic_type;
7192 }
7193
7194 static void semantic_shift_op(binary_expression_t *expression)
7195 {
7196         expression_t *const left            = expression->left;
7197         expression_t *const right           = expression->right;
7198         type_t       *const orig_type_left  = left->base.type;
7199         type_t       *const orig_type_right = right->base.type;
7200         type_t       *      type_left       = skip_typeref(orig_type_left);
7201         type_t       *      type_right      = skip_typeref(orig_type_right);
7202
7203         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
7204                 /* TODO: improve error message */
7205                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7206                         errorf(HERE, "operation needs integer types");
7207                 }
7208                 return;
7209         }
7210
7211         type_left  = promote_integer(type_left);
7212         type_right = promote_integer(type_right);
7213
7214         expression->left      = create_implicit_cast(left, type_left);
7215         expression->right     = create_implicit_cast(right, type_right);
7216         expression->base.type = type_left;
7217 }
7218
7219 static void semantic_add(binary_expression_t *expression)
7220 {
7221         expression_t *const left            = expression->left;
7222         expression_t *const right           = expression->right;
7223         type_t       *const orig_type_left  = left->base.type;
7224         type_t       *const orig_type_right = right->base.type;
7225         type_t       *const type_left       = skip_typeref(orig_type_left);
7226         type_t       *const type_right      = skip_typeref(orig_type_right);
7227
7228         /* § 6.5.6 */
7229         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7230                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7231                 expression->left  = create_implicit_cast(left, arithmetic_type);
7232                 expression->right = create_implicit_cast(right, arithmetic_type);
7233                 expression->base.type = arithmetic_type;
7234                 return;
7235         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7236                 check_pointer_arithmetic(&expression->base.source_position,
7237                                          type_left, orig_type_left);
7238                 expression->base.type = type_left;
7239         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
7240                 check_pointer_arithmetic(&expression->base.source_position,
7241                                          type_right, orig_type_right);
7242                 expression->base.type = type_right;
7243         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7244                 errorf(&expression->base.source_position,
7245                        "invalid operands to binary + ('%T', '%T')",
7246                        orig_type_left, orig_type_right);
7247         }
7248 }
7249
7250 static void semantic_sub(binary_expression_t *expression)
7251 {
7252         expression_t *const left            = expression->left;
7253         expression_t *const right           = expression->right;
7254         type_t       *const orig_type_left  = left->base.type;
7255         type_t       *const orig_type_right = right->base.type;
7256         type_t       *const type_left       = skip_typeref(orig_type_left);
7257         type_t       *const type_right      = skip_typeref(orig_type_right);
7258
7259         /* § 5.6.5 */
7260         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7261                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7262                 expression->left        = create_implicit_cast(left, arithmetic_type);
7263                 expression->right       = create_implicit_cast(right, arithmetic_type);
7264                 expression->base.type =  arithmetic_type;
7265                 return;
7266         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7267                 check_pointer_arithmetic(&expression->base.source_position,
7268                                          type_left, orig_type_left);
7269                 expression->base.type = type_left;
7270         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7271                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
7272                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
7273                 if (!types_compatible(unqual_left, unqual_right)) {
7274                         errorf(&expression->base.source_position,
7275                                "subtracting pointers to incompatible types '%T' and '%T'",
7276                                orig_type_left, orig_type_right);
7277                 } else if (!is_type_object(unqual_left)) {
7278                         if (is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
7279                                 warningf(&expression->base.source_position,
7280                                          "subtracting pointers to void");
7281                         } else {
7282                                 errorf(&expression->base.source_position,
7283                                        "subtracting pointers to non-object types '%T'",
7284                                        orig_type_left);
7285                         }
7286                 }
7287                 expression->base.type = type_ptrdiff_t;
7288         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7289                 errorf(HERE, "invalid operands of types '%T' and '%T' to binary '-'",
7290                        orig_type_left, orig_type_right);
7291         }
7292 }
7293
7294 /**
7295  * Check the semantics of comparison expressions.
7296  *
7297  * @param expression   The expression to check.
7298  */
7299 static void semantic_comparison(binary_expression_t *expression)
7300 {
7301         expression_t *left            = expression->left;
7302         expression_t *right           = expression->right;
7303         type_t       *orig_type_left  = left->base.type;
7304         type_t       *orig_type_right = right->base.type;
7305
7306         type_t *type_left  = skip_typeref(orig_type_left);
7307         type_t *type_right = skip_typeref(orig_type_right);
7308
7309         /* TODO non-arithmetic types */
7310         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7311                 /* test for signed vs unsigned compares */
7312                 if (warning.sign_compare &&
7313                     (expression->base.kind != EXPR_BINARY_EQUAL &&
7314                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
7315                     (is_type_signed(type_left) != is_type_signed(type_right))) {
7316
7317                         /* check if 1 of the operands is a constant, in this case we just
7318                          * check wether we can safely represent the resulting constant in
7319                          * the type of the other operand. */
7320                         expression_t *const_expr = NULL;
7321                         expression_t *other_expr = NULL;
7322
7323                         if (is_constant_expression(left)) {
7324                                 const_expr = left;
7325                                 other_expr = right;
7326                         } else if (is_constant_expression(right)) {
7327                                 const_expr = right;
7328                                 other_expr = left;
7329                         }
7330
7331                         if (const_expr != NULL) {
7332                                 type_t *other_type = skip_typeref(other_expr->base.type);
7333                                 long    val        = fold_constant(const_expr);
7334                                 /* TODO: check if val can be represented by other_type */
7335                                 (void) other_type;
7336                                 (void) val;
7337                         }
7338                         warningf(&expression->base.source_position,
7339                                  "comparison between signed and unsigned");
7340                 }
7341                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7342                 expression->left        = create_implicit_cast(left, arithmetic_type);
7343                 expression->right       = create_implicit_cast(right, arithmetic_type);
7344                 expression->base.type   = arithmetic_type;
7345                 if (warning.float_equal &&
7346                     (expression->base.kind == EXPR_BINARY_EQUAL ||
7347                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
7348                     is_type_float(arithmetic_type)) {
7349                         warningf(&expression->base.source_position,
7350                                  "comparing floating point with == or != is unsafe");
7351                 }
7352         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7353                 /* TODO check compatibility */
7354         } else if (is_type_pointer(type_left)) {
7355                 expression->right = create_implicit_cast(right, type_left);
7356         } else if (is_type_pointer(type_right)) {
7357                 expression->left = create_implicit_cast(left, type_right);
7358         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7359                 type_error_incompatible("invalid operands in comparison",
7360                                         &expression->base.source_position,
7361                                         type_left, type_right);
7362         }
7363         expression->base.type = type_int;
7364 }
7365
7366 /**
7367  * Checks if a compound type has constant fields.
7368  */
7369 static bool has_const_fields(const compound_type_t *type)
7370 {
7371         const scope_t       *scope       = &type->declaration->scope;
7372         const declaration_t *declaration = scope->declarations;
7373
7374         for (; declaration != NULL; declaration = declaration->next) {
7375                 if (declaration->namespc != NAMESPACE_NORMAL)
7376                         continue;
7377
7378                 const type_t *decl_type = skip_typeref(declaration->type);
7379                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
7380                         return true;
7381         }
7382         /* TODO */
7383         return false;
7384 }
7385
7386 static bool is_lvalue(const expression_t *expression)
7387 {
7388         switch (expression->kind) {
7389         case EXPR_REFERENCE:
7390         case EXPR_ARRAY_ACCESS:
7391         case EXPR_SELECT:
7392         case EXPR_UNARY_DEREFERENCE:
7393                 return true;
7394
7395         default:
7396                 return false;
7397         }
7398 }
7399
7400 static bool is_valid_assignment_lhs(expression_t const* const left)
7401 {
7402         type_t *const orig_type_left = revert_automatic_type_conversion(left);
7403         type_t *const type_left      = skip_typeref(orig_type_left);
7404
7405         if (!is_lvalue(left)) {
7406                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
7407                        left);
7408                 return false;
7409         }
7410
7411         if (is_type_array(type_left)) {
7412                 errorf(HERE, "cannot assign to arrays ('%E')", left);
7413                 return false;
7414         }
7415         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
7416                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
7417                        orig_type_left);
7418                 return false;
7419         }
7420         if (is_type_incomplete(type_left)) {
7421                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
7422                        left, orig_type_left);
7423                 return false;
7424         }
7425         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
7426                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
7427                        left, orig_type_left);
7428                 return false;
7429         }
7430
7431         return true;
7432 }
7433
7434 static void semantic_arithmetic_assign(binary_expression_t *expression)
7435 {
7436         expression_t *left            = expression->left;
7437         expression_t *right           = expression->right;
7438         type_t       *orig_type_left  = left->base.type;
7439         type_t       *orig_type_right = right->base.type;
7440
7441         if (!is_valid_assignment_lhs(left))
7442                 return;
7443
7444         type_t *type_left  = skip_typeref(orig_type_left);
7445         type_t *type_right = skip_typeref(orig_type_right);
7446
7447         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7448                 /* TODO: improve error message */
7449                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7450                         errorf(HERE, "operation needs arithmetic types");
7451                 }
7452                 return;
7453         }
7454
7455         /* combined instructions are tricky. We can't create an implicit cast on
7456          * the left side, because we need the uncasted form for the store.
7457          * The ast2firm pass has to know that left_type must be right_type
7458          * for the arithmetic operation and create a cast by itself */
7459         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7460         expression->right       = create_implicit_cast(right, arithmetic_type);
7461         expression->base.type   = type_left;
7462 }
7463
7464 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
7465 {
7466         expression_t *const left            = expression->left;
7467         expression_t *const right           = expression->right;
7468         type_t       *const orig_type_left  = left->base.type;
7469         type_t       *const orig_type_right = right->base.type;
7470         type_t       *const type_left       = skip_typeref(orig_type_left);
7471         type_t       *const type_right      = skip_typeref(orig_type_right);
7472
7473         if (!is_valid_assignment_lhs(left))
7474                 return;
7475
7476         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7477                 /* combined instructions are tricky. We can't create an implicit cast on
7478                  * the left side, because we need the uncasted form for the store.
7479                  * The ast2firm pass has to know that left_type must be right_type
7480                  * for the arithmetic operation and create a cast by itself */
7481                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
7482                 expression->right     = create_implicit_cast(right, arithmetic_type);
7483                 expression->base.type = type_left;
7484         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7485                 check_pointer_arithmetic(&expression->base.source_position,
7486                                          type_left, orig_type_left);
7487                 expression->base.type = type_left;
7488         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7489                 errorf(HERE, "incompatible types '%T' and '%T' in assignment", orig_type_left, orig_type_right);
7490         }
7491 }
7492
7493 /**
7494  * Check the semantic restrictions of a logical expression.
7495  */
7496 static void semantic_logical_op(binary_expression_t *expression)
7497 {
7498         expression_t *const left            = expression->left;
7499         expression_t *const right           = expression->right;
7500         type_t       *const orig_type_left  = left->base.type;
7501         type_t       *const orig_type_right = right->base.type;
7502         type_t       *const type_left       = skip_typeref(orig_type_left);
7503         type_t       *const type_right      = skip_typeref(orig_type_right);
7504
7505         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
7506                 /* TODO: improve error message */
7507                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7508                         errorf(HERE, "operation needs scalar types");
7509                 }
7510                 return;
7511         }
7512
7513         expression->base.type = type_int;
7514 }
7515
7516 /**
7517  * Check the semantic restrictions of a binary assign expression.
7518  */
7519 static void semantic_binexpr_assign(binary_expression_t *expression)
7520 {
7521         expression_t *left           = expression->left;
7522         type_t       *orig_type_left = left->base.type;
7523
7524         type_t *type_left = revert_automatic_type_conversion(left);
7525         type_left         = skip_typeref(orig_type_left);
7526
7527         if (!is_valid_assignment_lhs(left))
7528                 return;
7529
7530         assign_error_t error = semantic_assign(orig_type_left, expression->right);
7531         report_assign_error(error, orig_type_left, expression->right,
7532                         "assignment", &left->base.source_position);
7533         expression->right = create_implicit_cast(expression->right, orig_type_left);
7534         expression->base.type = orig_type_left;
7535 }
7536
7537 /**
7538  * Determine if the outermost operation (or parts thereof) of the given
7539  * expression has no effect in order to generate a warning about this fact.
7540  * Therefore in some cases this only examines some of the operands of the
7541  * expression (see comments in the function and examples below).
7542  * Examples:
7543  *   f() + 23;    // warning, because + has no effect
7544  *   x || f();    // no warning, because x controls execution of f()
7545  *   x ? y : f(); // warning, because y has no effect
7546  *   (void)x;     // no warning to be able to suppress the warning
7547  * This function can NOT be used for an "expression has definitely no effect"-
7548  * analysis. */
7549 static bool expression_has_effect(const expression_t *const expr)
7550 {
7551         switch (expr->kind) {
7552                 case EXPR_UNKNOWN:                   break;
7553                 case EXPR_INVALID:                   return true; /* do NOT warn */
7554                 case EXPR_REFERENCE:                 return false;
7555                 /* suppress the warning for microsoft __noop operations */
7556                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
7557                 case EXPR_CHARACTER_CONSTANT:        return false;
7558                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
7559                 case EXPR_STRING_LITERAL:            return false;
7560                 case EXPR_WIDE_STRING_LITERAL:       return false;
7561
7562                 case EXPR_CALL: {
7563                         const call_expression_t *const call = &expr->call;
7564                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
7565                                 return true;
7566
7567                         switch (call->function->builtin_symbol.symbol->ID) {
7568                                 case T___builtin_va_end: return true;
7569                                 default:                 return false;
7570                         }
7571                 }
7572
7573                 /* Generate the warning if either the left or right hand side of a
7574                  * conditional expression has no effect */
7575                 case EXPR_CONDITIONAL: {
7576                         const conditional_expression_t *const cond = &expr->conditional;
7577                         return
7578                                 expression_has_effect(cond->true_expression) &&
7579                                 expression_has_effect(cond->false_expression);
7580                 }
7581
7582                 case EXPR_SELECT:                    return false;
7583                 case EXPR_ARRAY_ACCESS:              return false;
7584                 case EXPR_SIZEOF:                    return false;
7585                 case EXPR_CLASSIFY_TYPE:             return false;
7586                 case EXPR_ALIGNOF:                   return false;
7587
7588                 case EXPR_FUNCNAME:                  return false;
7589                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
7590                 case EXPR_BUILTIN_CONSTANT_P:        return false;
7591                 case EXPR_BUILTIN_PREFETCH:          return true;
7592                 case EXPR_OFFSETOF:                  return false;
7593                 case EXPR_VA_START:                  return true;
7594                 case EXPR_VA_ARG:                    return true;
7595                 case EXPR_STATEMENT:                 return true; // TODO
7596                 case EXPR_COMPOUND_LITERAL:          return false;
7597
7598                 case EXPR_UNARY_NEGATE:              return false;
7599                 case EXPR_UNARY_PLUS:                return false;
7600                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
7601                 case EXPR_UNARY_NOT:                 return false;
7602                 case EXPR_UNARY_DEREFERENCE:         return false;
7603                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
7604                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
7605                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
7606                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
7607                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
7608
7609                 /* Treat void casts as if they have an effect in order to being able to
7610                  * suppress the warning */
7611                 case EXPR_UNARY_CAST: {
7612                         type_t *const type = skip_typeref(expr->base.type);
7613                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
7614                 }
7615
7616                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
7617                 case EXPR_UNARY_ASSUME:              return true;
7618
7619                 case EXPR_BINARY_ADD:                return false;
7620                 case EXPR_BINARY_SUB:                return false;
7621                 case EXPR_BINARY_MUL:                return false;
7622                 case EXPR_BINARY_DIV:                return false;
7623                 case EXPR_BINARY_MOD:                return false;
7624                 case EXPR_BINARY_EQUAL:              return false;
7625                 case EXPR_BINARY_NOTEQUAL:           return false;
7626                 case EXPR_BINARY_LESS:               return false;
7627                 case EXPR_BINARY_LESSEQUAL:          return false;
7628                 case EXPR_BINARY_GREATER:            return false;
7629                 case EXPR_BINARY_GREATEREQUAL:       return false;
7630                 case EXPR_BINARY_BITWISE_AND:        return false;
7631                 case EXPR_BINARY_BITWISE_OR:         return false;
7632                 case EXPR_BINARY_BITWISE_XOR:        return false;
7633                 case EXPR_BINARY_SHIFTLEFT:          return false;
7634                 case EXPR_BINARY_SHIFTRIGHT:         return false;
7635                 case EXPR_BINARY_ASSIGN:             return true;
7636                 case EXPR_BINARY_MUL_ASSIGN:         return true;
7637                 case EXPR_BINARY_DIV_ASSIGN:         return true;
7638                 case EXPR_BINARY_MOD_ASSIGN:         return true;
7639                 case EXPR_BINARY_ADD_ASSIGN:         return true;
7640                 case EXPR_BINARY_SUB_ASSIGN:         return true;
7641                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
7642                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
7643                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
7644                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
7645                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
7646
7647                 /* Only examine the right hand side of && and ||, because the left hand
7648                  * side already has the effect of controlling the execution of the right
7649                  * hand side */
7650                 case EXPR_BINARY_LOGICAL_AND:
7651                 case EXPR_BINARY_LOGICAL_OR:
7652                 /* Only examine the right hand side of a comma expression, because the left
7653                  * hand side has a separate warning */
7654                 case EXPR_BINARY_COMMA:
7655                         return expression_has_effect(expr->binary.right);
7656
7657                 case EXPR_BINARY_BUILTIN_EXPECT:     return true;
7658                 case EXPR_BINARY_ISGREATER:          return false;
7659                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
7660                 case EXPR_BINARY_ISLESS:             return false;
7661                 case EXPR_BINARY_ISLESSEQUAL:        return false;
7662                 case EXPR_BINARY_ISLESSGREATER:      return false;
7663                 case EXPR_BINARY_ISUNORDERED:        return false;
7664         }
7665
7666         internal_errorf(HERE, "unexpected expression");
7667 }
7668
7669 static void semantic_comma(binary_expression_t *expression)
7670 {
7671         if (warning.unused_value) {
7672                 const expression_t *const left = expression->left;
7673                 if (!expression_has_effect(left)) {
7674                         warningf(&left->base.source_position,
7675                                  "left-hand operand of comma expression has no effect");
7676                 }
7677         }
7678         expression->base.type = expression->right->base.type;
7679 }
7680
7681 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr)  \
7682 static expression_t *parse_##binexpression_type(unsigned precedence,      \
7683                                                 expression_t *left)       \
7684 {                                                                         \
7685         eat(token_type);                                                      \
7686         source_position_t pos = *HERE;                                        \
7687                                                                           \
7688         expression_t *right = parse_sub_expression(precedence + lr);          \
7689                                                                           \
7690         expression_t *binexpr = allocate_expression_zero(binexpression_type); \
7691         binexpr->base.source_position = pos;                                  \
7692         binexpr->binary.left  = left;                                         \
7693         binexpr->binary.right = right;                                        \
7694         sfunc(&binexpr->binary);                                              \
7695                                                                           \
7696         return binexpr;                                                       \
7697 }
7698
7699 CREATE_BINEXPR_PARSER(',', EXPR_BINARY_COMMA,    semantic_comma, 1)
7700 CREATE_BINEXPR_PARSER('*', EXPR_BINARY_MUL,      semantic_binexpr_arithmetic, 1)
7701 CREATE_BINEXPR_PARSER('/', EXPR_BINARY_DIV,      semantic_binexpr_arithmetic, 1)
7702 CREATE_BINEXPR_PARSER('%', EXPR_BINARY_MOD,      semantic_binexpr_arithmetic, 1)
7703 CREATE_BINEXPR_PARSER('+', EXPR_BINARY_ADD,      semantic_add, 1)
7704 CREATE_BINEXPR_PARSER('-', EXPR_BINARY_SUB,      semantic_sub, 1)
7705 CREATE_BINEXPR_PARSER('<', EXPR_BINARY_LESS,     semantic_comparison, 1)
7706 CREATE_BINEXPR_PARSER('>', EXPR_BINARY_GREATER,  semantic_comparison, 1)
7707 CREATE_BINEXPR_PARSER('=', EXPR_BINARY_ASSIGN,   semantic_binexpr_assign, 0)
7708
7709 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,
7710                       semantic_comparison, 1)
7711 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,
7712                       semantic_comparison, 1)
7713 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,
7714                       semantic_comparison, 1)
7715 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,
7716                       semantic_comparison, 1)
7717
7718 CREATE_BINEXPR_PARSER('&', EXPR_BINARY_BITWISE_AND,
7719                       semantic_binexpr_arithmetic, 1)
7720 CREATE_BINEXPR_PARSER('|', EXPR_BINARY_BITWISE_OR,
7721                       semantic_binexpr_arithmetic, 1)
7722 CREATE_BINEXPR_PARSER('^', EXPR_BINARY_BITWISE_XOR,
7723                       semantic_binexpr_arithmetic, 1)
7724 CREATE_BINEXPR_PARSER(T_ANDAND, EXPR_BINARY_LOGICAL_AND,
7725                       semantic_logical_op, 1)
7726 CREATE_BINEXPR_PARSER(T_PIPEPIPE, EXPR_BINARY_LOGICAL_OR,
7727                       semantic_logical_op, 1)
7728 CREATE_BINEXPR_PARSER(T_LESSLESS, EXPR_BINARY_SHIFTLEFT,
7729                       semantic_shift_op, 1)
7730 CREATE_BINEXPR_PARSER(T_GREATERGREATER, EXPR_BINARY_SHIFTRIGHT,
7731                       semantic_shift_op, 1)
7732 CREATE_BINEXPR_PARSER(T_PLUSEQUAL, EXPR_BINARY_ADD_ASSIGN,
7733                       semantic_arithmetic_addsubb_assign, 0)
7734 CREATE_BINEXPR_PARSER(T_MINUSEQUAL, EXPR_BINARY_SUB_ASSIGN,
7735                       semantic_arithmetic_addsubb_assign, 0)
7736 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, EXPR_BINARY_MUL_ASSIGN,
7737                       semantic_arithmetic_assign, 0)
7738 CREATE_BINEXPR_PARSER(T_SLASHEQUAL, EXPR_BINARY_DIV_ASSIGN,
7739                       semantic_arithmetic_assign, 0)
7740 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, EXPR_BINARY_MOD_ASSIGN,
7741                       semantic_arithmetic_assign, 0)
7742 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, EXPR_BINARY_SHIFTLEFT_ASSIGN,
7743                       semantic_arithmetic_assign, 0)
7744 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, EXPR_BINARY_SHIFTRIGHT_ASSIGN,
7745                       semantic_arithmetic_assign, 0)
7746 CREATE_BINEXPR_PARSER(T_ANDEQUAL, EXPR_BINARY_BITWISE_AND_ASSIGN,
7747                       semantic_arithmetic_assign, 0)
7748 CREATE_BINEXPR_PARSER(T_PIPEEQUAL, EXPR_BINARY_BITWISE_OR_ASSIGN,
7749                       semantic_arithmetic_assign, 0)
7750 CREATE_BINEXPR_PARSER(T_CARETEQUAL, EXPR_BINARY_BITWISE_XOR_ASSIGN,
7751                       semantic_arithmetic_assign, 0)
7752
7753 static expression_t *parse_sub_expression(unsigned precedence)
7754 {
7755         if (token.type < 0) {
7756                 return expected_expression_error();
7757         }
7758
7759         expression_parser_function_t *parser
7760                 = &expression_parsers[token.type];
7761         source_position_t             source_position = token.source_position;
7762         expression_t                 *left;
7763
7764         if (parser->parser != NULL) {
7765                 left = parser->parser(parser->precedence);
7766         } else {
7767                 left = parse_primary_expression();
7768         }
7769         assert(left != NULL);
7770         left->base.source_position = source_position;
7771
7772         while(true) {
7773                 if (token.type < 0) {
7774                         return expected_expression_error();
7775                 }
7776
7777                 parser = &expression_parsers[token.type];
7778                 if (parser->infix_parser == NULL)
7779                         break;
7780                 if (parser->infix_precedence < precedence)
7781                         break;
7782
7783                 left = parser->infix_parser(parser->infix_precedence, left);
7784
7785                 assert(left != NULL);
7786                 assert(left->kind != EXPR_UNKNOWN);
7787                 left->base.source_position = source_position;
7788         }
7789
7790         return left;
7791 }
7792
7793 /**
7794  * Parse an expression.
7795  */
7796 static expression_t *parse_expression(void)
7797 {
7798         return parse_sub_expression(1);
7799 }
7800
7801 /**
7802  * Register a parser for a prefix-like operator with given precedence.
7803  *
7804  * @param parser      the parser function
7805  * @param token_type  the token type of the prefix token
7806  * @param precedence  the precedence of the operator
7807  */
7808 static void register_expression_parser(parse_expression_function parser,
7809                                        int token_type, unsigned precedence)
7810 {
7811         expression_parser_function_t *entry = &expression_parsers[token_type];
7812
7813         if (entry->parser != NULL) {
7814                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
7815                 panic("trying to register multiple expression parsers for a token");
7816         }
7817         entry->parser     = parser;
7818         entry->precedence = precedence;
7819 }
7820
7821 /**
7822  * Register a parser for an infix operator with given precedence.
7823  *
7824  * @param parser      the parser function
7825  * @param token_type  the token type of the infix operator
7826  * @param precedence  the precedence of the operator
7827  */
7828 static void register_infix_parser(parse_expression_infix_function parser,
7829                 int token_type, unsigned precedence)
7830 {
7831         expression_parser_function_t *entry = &expression_parsers[token_type];
7832
7833         if (entry->infix_parser != NULL) {
7834                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
7835                 panic("trying to register multiple infix expression parsers for a "
7836                       "token");
7837         }
7838         entry->infix_parser     = parser;
7839         entry->infix_precedence = precedence;
7840 }
7841
7842 /**
7843  * Initialize the expression parsers.
7844  */
7845 static void init_expression_parsers(void)
7846 {
7847         memset(&expression_parsers, 0, sizeof(expression_parsers));
7848
7849         register_infix_parser(parse_array_expression,         '[',              30);
7850         register_infix_parser(parse_call_expression,          '(',              30);
7851         register_infix_parser(parse_select_expression,        '.',              30);
7852         register_infix_parser(parse_select_expression,        T_MINUSGREATER,   30);
7853         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,
7854                                                               T_PLUSPLUS,       30);
7855         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,
7856                                                               T_MINUSMINUS,     30);
7857
7858         register_infix_parser(parse_EXPR_BINARY_MUL,          '*',              17);
7859         register_infix_parser(parse_EXPR_BINARY_DIV,          '/',              17);
7860         register_infix_parser(parse_EXPR_BINARY_MOD,          '%',              17);
7861         register_infix_parser(parse_EXPR_BINARY_ADD,          '+',              16);
7862         register_infix_parser(parse_EXPR_BINARY_SUB,          '-',              16);
7863         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,    T_LESSLESS,       15);
7864         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,   T_GREATERGREATER, 15);
7865         register_infix_parser(parse_EXPR_BINARY_LESS,         '<',              14);
7866         register_infix_parser(parse_EXPR_BINARY_GREATER,      '>',              14);
7867         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,    T_LESSEQUAL,      14);
7868         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL, T_GREATEREQUAL,   14);
7869         register_infix_parser(parse_EXPR_BINARY_EQUAL,        T_EQUALEQUAL,     13);
7870         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,
7871                                                     T_EXCLAMATIONMARKEQUAL, 13);
7872         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,  '&',              12);
7873         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,  '^',              11);
7874         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,   '|',              10);
7875         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,  T_ANDAND,          9);
7876         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,   T_PIPEPIPE,        8);
7877         register_infix_parser(parse_conditional_expression,   '?',               7);
7878         register_infix_parser(parse_EXPR_BINARY_ASSIGN,       '=',               2);
7879         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,   T_PLUSEQUAL,       2);
7880         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,   T_MINUSEQUAL,      2);
7881         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,   T_ASTERISKEQUAL,   2);
7882         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,   T_SLASHEQUAL,      2);
7883         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,   T_PERCENTEQUAL,    2);
7884         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,
7885                                                                 T_LESSLESSEQUAL, 2);
7886         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,
7887                                                           T_GREATERGREATEREQUAL, 2);
7888         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN,
7889                                                                      T_ANDEQUAL, 2);
7890         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,
7891                                                                     T_PIPEEQUAL, 2);
7892         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN,
7893                                                                    T_CARETEQUAL, 2);
7894
7895         register_infix_parser(parse_EXPR_BINARY_COMMA,        ',',               1);
7896
7897         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-',      25);
7898         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+',      25);
7899         register_expression_parser(parse_EXPR_UNARY_NOT,              '!',      25);
7900         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~',      25);
7901         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*',      25);
7902         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&',      25);
7903         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT,
7904                                                                   T_PLUSPLUS,   25);
7905         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT,
7906                                                                   T_MINUSMINUS, 25);
7907         register_expression_parser(parse_sizeof,                      T_sizeof, 25);
7908         register_expression_parser(parse_alignof,                T___alignof__, 25);
7909         register_expression_parser(parse_extension,            T___extension__, 25);
7910         register_expression_parser(parse_builtin_classify_type,
7911                                                      T___builtin_classify_type, 25);
7912 }
7913
7914 /**
7915  * Parse a asm statement arguments specification.
7916  */
7917 static asm_argument_t *parse_asm_arguments(bool is_out)
7918 {
7919         asm_argument_t *result = NULL;
7920         asm_argument_t *last   = NULL;
7921
7922         while (token.type == T_STRING_LITERAL || token.type == '[') {
7923                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
7924                 memset(argument, 0, sizeof(argument[0]));
7925
7926                 if (token.type == '[') {
7927                         eat('[');
7928                         if (token.type != T_IDENTIFIER) {
7929                                 parse_error_expected("while parsing asm argument",
7930                                                      T_IDENTIFIER, NULL);
7931                                 return NULL;
7932                         }
7933                         argument->symbol = token.v.symbol;
7934
7935                         expect(']');
7936                 }
7937
7938                 argument->constraints = parse_string_literals();
7939                 expect('(');
7940                 add_anchor_token(')');
7941                 expression_t *expression = parse_expression();
7942                 rem_anchor_token(')');
7943                 if (is_out) {
7944                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
7945                          * change size or type representation (e.g. int -> long is ok, but
7946                          * int -> float is not) */
7947                         if (expression->kind == EXPR_UNARY_CAST) {
7948                                 type_t      *const type = expression->base.type;
7949                                 type_kind_t  const kind = type->kind;
7950                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
7951                                         unsigned flags;
7952                                         unsigned size;
7953                                         if (kind == TYPE_ATOMIC) {
7954                                                 atomic_type_kind_t const akind = type->atomic.akind;
7955                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
7956                                                 size  = get_atomic_type_size(akind);
7957                                         } else {
7958                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
7959                                                 size  = get_atomic_type_size(get_intptr_kind());
7960                                         }
7961
7962                                         do {
7963                                                 expression_t *const value      = expression->unary.value;
7964                                                 type_t       *const value_type = value->base.type;
7965                                                 type_kind_t   const value_kind = value_type->kind;
7966
7967                                                 unsigned value_flags;
7968                                                 unsigned value_size;
7969                                                 if (value_kind == TYPE_ATOMIC) {
7970                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
7971                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
7972                                                         value_size  = get_atomic_type_size(value_akind);
7973                                                 } else if (value_kind == TYPE_POINTER) {
7974                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
7975                                                         value_size  = get_atomic_type_size(get_intptr_kind());
7976                                                 } else {
7977                                                         break;
7978                                                 }
7979
7980                                                 if (value_flags != flags || value_size != size)
7981                                                         break;
7982
7983                                                 expression = value;
7984                                         } while (expression->kind == EXPR_UNARY_CAST);
7985                                 }
7986                         }
7987
7988                         if (!is_lvalue(expression)) {
7989                                 errorf(&expression->base.source_position,
7990                                        "asm output argument is not an lvalue");
7991                         }
7992                 }
7993                 argument->expression = expression;
7994                 expect(')');
7995
7996                 set_address_taken(expression, true);
7997
7998                 if (last != NULL) {
7999                         last->next = argument;
8000                 } else {
8001                         result = argument;
8002                 }
8003                 last = argument;
8004
8005                 if (token.type != ',')
8006                         break;
8007                 eat(',');
8008         }
8009
8010         return result;
8011 end_error:
8012         return NULL;
8013 }
8014
8015 /**
8016  * Parse a asm statement clobber specification.
8017  */
8018 static asm_clobber_t *parse_asm_clobbers(void)
8019 {
8020         asm_clobber_t *result = NULL;
8021         asm_clobber_t *last   = NULL;
8022
8023         while(token.type == T_STRING_LITERAL) {
8024                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
8025                 clobber->clobber       = parse_string_literals();
8026
8027                 if (last != NULL) {
8028                         last->next = clobber;
8029                 } else {
8030                         result = clobber;
8031                 }
8032                 last = clobber;
8033
8034                 if (token.type != ',')
8035                         break;
8036                 eat(',');
8037         }
8038
8039         return result;
8040 }
8041
8042 /**
8043  * Parse an asm statement.
8044  */
8045 static statement_t *parse_asm_statement(void)
8046 {
8047         eat(T_asm);
8048
8049         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
8050         statement->base.source_position = token.source_position;
8051
8052         asm_statement_t *asm_statement = &statement->asms;
8053
8054         if (token.type == T_volatile) {
8055                 next_token();
8056                 asm_statement->is_volatile = true;
8057         }
8058
8059         expect('(');
8060         add_anchor_token(')');
8061         add_anchor_token(':');
8062         asm_statement->asm_text = parse_string_literals();
8063
8064         if (token.type != ':') {
8065                 rem_anchor_token(':');
8066                 goto end_of_asm;
8067         }
8068         eat(':');
8069
8070         asm_statement->outputs = parse_asm_arguments(true);
8071         if (token.type != ':') {
8072                 rem_anchor_token(':');
8073                 goto end_of_asm;
8074         }
8075         eat(':');
8076
8077         asm_statement->inputs = parse_asm_arguments(false);
8078         if (token.type != ':') {
8079                 rem_anchor_token(':');
8080                 goto end_of_asm;
8081         }
8082         rem_anchor_token(':');
8083         eat(':');
8084
8085         asm_statement->clobbers = parse_asm_clobbers();
8086
8087 end_of_asm:
8088         rem_anchor_token(')');
8089         expect(')');
8090         expect(';');
8091
8092         if (asm_statement->outputs == NULL) {
8093                 /* GCC: An 'asm' instruction without any output operands will be treated
8094                  * identically to a volatile 'asm' instruction. */
8095                 asm_statement->is_volatile = true;
8096         }
8097
8098         return statement;
8099 end_error:
8100         return create_invalid_statement();
8101 }
8102
8103 /**
8104  * Parse a case statement.
8105  */
8106 static statement_t *parse_case_statement(void)
8107 {
8108         eat(T_case);
8109
8110         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8111         source_position_t *const pos       = &statement->base.source_position;
8112
8113         *pos                             = token.source_position;
8114         statement->case_label.expression = parse_expression();
8115
8116         PUSH_PARENT(statement);
8117
8118         if (c_mode & _GNUC) {
8119                 if (token.type == T_DOTDOTDOT) {
8120                         next_token();
8121                         statement->case_label.end_range = parse_expression();
8122                 }
8123         }
8124
8125         expect(':');
8126
8127         if (! is_constant_expression(statement->case_label.expression)) {
8128                 errorf(pos, "case label does not reduce to an integer constant");
8129         } else if (current_switch != NULL) {
8130                 /* Check for duplicate case values */
8131                 /* FIXME slow */
8132                 long const val = fold_constant(statement->case_label.expression);
8133                 for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
8134                         expression_t const* const e = l->expression;
8135                         if (e == NULL || !is_constant_expression(e) || fold_constant(e) != val)
8136                                 continue;
8137
8138                         errorf(pos, "duplicate case value");
8139                         errorf(&l->base.source_position, "previously used here");
8140                         break;
8141                 }
8142
8143                 /* link all cases into the switch statement */
8144                 if (current_switch->last_case == NULL) {
8145                         current_switch->first_case      = &statement->case_label;
8146                 } else {
8147                         current_switch->last_case->next = &statement->case_label;
8148                 }
8149                 current_switch->last_case = &statement->case_label;
8150         } else {
8151                 errorf(pos, "case label not within a switch statement");
8152         }
8153
8154         statement_t *const inner_stmt = parse_statement();
8155         statement->case_label.statement = inner_stmt;
8156         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8157                 errorf(&inner_stmt->base.source_position, "declaration after case label");
8158         }
8159
8160         POP_PARENT;
8161         return statement;
8162 end_error:
8163         POP_PARENT;
8164         return create_invalid_statement();
8165 }
8166
8167 /**
8168  * Finds an existing default label of a switch statement.
8169  */
8170 static case_label_statement_t *
8171 find_default_label(const switch_statement_t *statement)
8172 {
8173         case_label_statement_t *label = statement->first_case;
8174         for ( ; label != NULL; label = label->next) {
8175                 if (label->expression == NULL)
8176                         return label;
8177         }
8178         return NULL;
8179 }
8180
8181 /**
8182  * Parse a default statement.
8183  */
8184 static statement_t *parse_default_statement(void)
8185 {
8186         eat(T_default);
8187
8188         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8189         statement->base.source_position = token.source_position;
8190
8191         PUSH_PARENT(statement);
8192
8193         expect(':');
8194         if (current_switch != NULL) {
8195                 const case_label_statement_t *def_label = find_default_label(current_switch);
8196                 if (def_label != NULL) {
8197                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
8198                                &def_label->base.source_position);
8199                 } else {
8200                         /* link all cases into the switch statement */
8201                         if (current_switch->last_case == NULL) {
8202                                 current_switch->first_case      = &statement->case_label;
8203                         } else {
8204                                 current_switch->last_case->next = &statement->case_label;
8205                         }
8206                         current_switch->last_case = &statement->case_label;
8207                 }
8208         } else {
8209                 errorf(&statement->base.source_position,
8210                         "'default' label not within a switch statement");
8211         }
8212
8213         statement_t *const inner_stmt = parse_statement();
8214         statement->case_label.statement = inner_stmt;
8215         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8216                 errorf(&inner_stmt->base.source_position, "declaration after default label");
8217         }
8218
8219         POP_PARENT;
8220         return statement;
8221 end_error:
8222         POP_PARENT;
8223         return create_invalid_statement();
8224 }
8225
8226 /**
8227  * Return the declaration for a given label symbol or create a new one.
8228  *
8229  * @param symbol  the symbol of the label
8230  */
8231 static declaration_t *get_label(symbol_t *symbol)
8232 {
8233         declaration_t *candidate = get_declaration(symbol, NAMESPACE_LABEL);
8234         assert(current_function != NULL);
8235         /* if we found a label in the same function, then we already created the
8236          * declaration */
8237         if (candidate != NULL
8238                         && candidate->parent_scope == &current_function->scope) {
8239                 return candidate;
8240         }
8241
8242         /* otherwise we need to create a new one */
8243         declaration_t *const declaration = allocate_declaration_zero();
8244         declaration->namespc       = NAMESPACE_LABEL;
8245         declaration->symbol        = symbol;
8246
8247         label_push(declaration);
8248
8249         return declaration;
8250 }
8251
8252 /**
8253  * Parse a label statement.
8254  */
8255 static statement_t *parse_label_statement(void)
8256 {
8257         assert(token.type == T_IDENTIFIER);
8258         symbol_t *symbol = token.v.symbol;
8259         next_token();
8260
8261         declaration_t *label = get_label(symbol);
8262
8263         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
8264         statement->base.source_position = token.source_position;
8265         statement->label.label          = label;
8266
8267         PUSH_PARENT(statement);
8268
8269         /* if source position is already set then the label is defined twice,
8270          * otherwise it was just mentioned in a goto so far */
8271         if (label->source_position.input_name != NULL) {
8272                 errorf(HERE, "duplicate label '%Y' (declared %P)",
8273                        symbol, &label->source_position);
8274         } else {
8275                 label->source_position = token.source_position;
8276                 label->init.statement  = statement;
8277         }
8278
8279         eat(':');
8280
8281         if (token.type == '}') {
8282                 /* TODO only warn? */
8283                 if (false) {
8284                         warningf(HERE, "label at end of compound statement");
8285                         statement->label.statement = create_empty_statement();
8286                 } else {
8287                         errorf(HERE, "label at end of compound statement");
8288                         statement->label.statement = create_invalid_statement();
8289                 }
8290         } else if (token.type == ';') {
8291                 /* Eat an empty statement here, to avoid the warning about an empty
8292                  * statement after a label.  label:; is commonly used to have a label
8293                  * before a closing brace. */
8294                 statement->label.statement = create_empty_statement();
8295                 next_token();
8296         } else {
8297                 statement_t *const inner_stmt = parse_statement();
8298                 statement->label.statement = inner_stmt;
8299                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
8300                         errorf(&inner_stmt->base.source_position, "declaration after label");
8301                 }
8302         }
8303
8304         /* remember the labels in a list for later checking */
8305         if (label_last == NULL) {
8306                 label_first = &statement->label;
8307         } else {
8308                 label_last->next = &statement->label;
8309         }
8310         label_last = &statement->label;
8311
8312         POP_PARENT;
8313         return statement;
8314 }
8315
8316 /**
8317  * Parse an if statement.
8318  */
8319 static statement_t *parse_if(void)
8320 {
8321         eat(T_if);
8322
8323         statement_t *statement          = allocate_statement_zero(STATEMENT_IF);
8324         statement->base.source_position = token.source_position;
8325
8326         PUSH_PARENT(statement);
8327
8328         expect('(');
8329         add_anchor_token(')');
8330         statement->ifs.condition = parse_expression();
8331         rem_anchor_token(')');
8332         expect(')');
8333
8334         add_anchor_token(T_else);
8335         statement->ifs.true_statement = parse_statement();
8336         rem_anchor_token(T_else);
8337
8338         if (token.type == T_else) {
8339                 next_token();
8340                 statement->ifs.false_statement = parse_statement();
8341         }
8342
8343         POP_PARENT;
8344         return statement;
8345 end_error:
8346         POP_PARENT;
8347         return create_invalid_statement();
8348 }
8349
8350 /**
8351  * Parse a switch statement.
8352  */
8353 static statement_t *parse_switch(void)
8354 {
8355         eat(T_switch);
8356
8357         statement_t *statement          = allocate_statement_zero(STATEMENT_SWITCH);
8358         statement->base.source_position = token.source_position;
8359
8360         PUSH_PARENT(statement);
8361
8362         expect('(');
8363         expression_t *const expr = parse_expression();
8364         type_t       *      type = skip_typeref(expr->base.type);
8365         if (is_type_integer(type)) {
8366                 type = promote_integer(type);
8367         } else if (is_type_valid(type)) {
8368                 errorf(&expr->base.source_position,
8369                        "switch quantity is not an integer, but '%T'", type);
8370                 type = type_error_type;
8371         }
8372         statement->switchs.expression = create_implicit_cast(expr, type);
8373         expect(')');
8374
8375         switch_statement_t *rem = current_switch;
8376         current_switch          = &statement->switchs;
8377         statement->switchs.body = parse_statement();
8378         current_switch          = rem;
8379
8380         if (warning.switch_default &&
8381            find_default_label(&statement->switchs) == NULL) {
8382                 warningf(&statement->base.source_position, "switch has no default case");
8383         }
8384
8385         POP_PARENT;
8386         return statement;
8387 end_error:
8388         POP_PARENT;
8389         return create_invalid_statement();
8390 }
8391
8392 static statement_t *parse_loop_body(statement_t *const loop)
8393 {
8394         statement_t *const rem = current_loop;
8395         current_loop = loop;
8396
8397         statement_t *const body = parse_statement();
8398
8399         current_loop = rem;
8400         return body;
8401 }
8402
8403 /**
8404  * Parse a while statement.
8405  */
8406 static statement_t *parse_while(void)
8407 {
8408         eat(T_while);
8409
8410         statement_t *statement          = allocate_statement_zero(STATEMENT_WHILE);
8411         statement->base.source_position = token.source_position;
8412
8413         PUSH_PARENT(statement);
8414
8415         expect('(');
8416         add_anchor_token(')');
8417         statement->whiles.condition = parse_expression();
8418         rem_anchor_token(')');
8419         expect(')');
8420
8421         statement->whiles.body = parse_loop_body(statement);
8422
8423         POP_PARENT;
8424         return statement;
8425 end_error:
8426         POP_PARENT;
8427         return create_invalid_statement();
8428 }
8429
8430 /**
8431  * Parse a do statement.
8432  */
8433 static statement_t *parse_do(void)
8434 {
8435         eat(T_do);
8436
8437         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
8438         statement->base.source_position = token.source_position;
8439
8440         PUSH_PARENT(statement)
8441
8442         add_anchor_token(T_while);
8443         statement->do_while.body = parse_loop_body(statement);
8444         rem_anchor_token(T_while);
8445
8446         expect(T_while);
8447         expect('(');
8448         add_anchor_token(')');
8449         statement->do_while.condition = parse_expression();
8450         rem_anchor_token(')');
8451         expect(')');
8452         expect(';');
8453
8454         POP_PARENT;
8455         return statement;
8456 end_error:
8457         POP_PARENT;
8458         return create_invalid_statement();
8459 }
8460
8461 /**
8462  * Parse a for statement.
8463  */
8464 static statement_t *parse_for(void)
8465 {
8466         eat(T_for);
8467
8468         statement_t *statement          = allocate_statement_zero(STATEMENT_FOR);
8469         statement->base.source_position = token.source_position;
8470
8471         PUSH_PARENT(statement);
8472
8473         int      top        = environment_top();
8474         scope_t *last_scope = scope;
8475         set_scope(&statement->fors.scope);
8476
8477         expect('(');
8478         add_anchor_token(')');
8479
8480         if (token.type != ';') {
8481                 if (is_declaration_specifier(&token, false)) {
8482                         parse_declaration(record_declaration);
8483                 } else {
8484                         add_anchor_token(';');
8485                         expression_t *const init = parse_expression();
8486                         statement->fors.initialisation = init;
8487                         if (warning.unused_value && !expression_has_effect(init)) {
8488                                 warningf(&init->base.source_position,
8489                                          "initialisation of 'for'-statement has no effect");
8490                         }
8491                         rem_anchor_token(';');
8492                         expect(';');
8493                 }
8494         } else {
8495                 expect(';');
8496         }
8497
8498         if (token.type != ';') {
8499                 add_anchor_token(';');
8500                 statement->fors.condition = parse_expression();
8501                 rem_anchor_token(';');
8502         }
8503         expect(';');
8504         if (token.type != ')') {
8505                 expression_t *const step = parse_expression();
8506                 statement->fors.step = step;
8507                 if (warning.unused_value && !expression_has_effect(step)) {
8508                         warningf(&step->base.source_position,
8509                                  "step of 'for'-statement has no effect");
8510                 }
8511         }
8512         rem_anchor_token(')');
8513         expect(')');
8514         statement->fors.body = parse_loop_body(statement);
8515
8516         assert(scope == &statement->fors.scope);
8517         set_scope(last_scope);
8518         environment_pop_to(top);
8519
8520         POP_PARENT;
8521         return statement;
8522
8523 end_error:
8524         POP_PARENT;
8525         rem_anchor_token(')');
8526         assert(scope == &statement->fors.scope);
8527         set_scope(last_scope);
8528         environment_pop_to(top);
8529
8530         return create_invalid_statement();
8531 }
8532
8533 /**
8534  * Parse a goto statement.
8535  */
8536 static statement_t *parse_goto(void)
8537 {
8538         eat(T_goto);
8539
8540         if (token.type != T_IDENTIFIER) {
8541                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
8542                 eat_statement();
8543                 goto end_error;
8544         }
8545         symbol_t *symbol = token.v.symbol;
8546         next_token();
8547
8548         declaration_t *label = get_label(symbol);
8549
8550         statement_t *statement          = allocate_statement_zero(STATEMENT_GOTO);
8551         statement->base.source_position = token.source_position;
8552
8553         statement->gotos.label = label;
8554
8555         /* remember the goto's in a list for later checking */
8556         if (goto_last == NULL) {
8557                 goto_first = &statement->gotos;
8558         } else {
8559                 goto_last->next = &statement->gotos;
8560         }
8561         goto_last = &statement->gotos;
8562
8563         expect(';');
8564
8565         return statement;
8566 end_error:
8567         return create_invalid_statement();
8568 }
8569
8570 /**
8571  * Parse a continue statement.
8572  */
8573 static statement_t *parse_continue(void)
8574 {
8575         statement_t *statement;
8576         if (current_loop == NULL) {
8577                 errorf(HERE, "continue statement not within loop");
8578                 statement = create_invalid_statement();
8579         } else {
8580                 statement = allocate_statement_zero(STATEMENT_CONTINUE);
8581
8582                 statement->base.source_position = token.source_position;
8583         }
8584
8585         eat(T_continue);
8586         expect(';');
8587
8588         return statement;
8589 end_error:
8590         return create_invalid_statement();
8591 }
8592
8593 /**
8594  * Parse a break statement.
8595  */
8596 static statement_t *parse_break(void)
8597 {
8598         statement_t *statement;
8599         if (current_switch == NULL && current_loop == NULL) {
8600                 errorf(HERE, "break statement not within loop or switch");
8601                 statement = create_invalid_statement();
8602         } else {
8603                 statement = allocate_statement_zero(STATEMENT_BREAK);
8604
8605                 statement->base.source_position = token.source_position;
8606         }
8607
8608         eat(T_break);
8609         expect(';');
8610
8611         return statement;
8612 end_error:
8613         return create_invalid_statement();
8614 }
8615
8616 /**
8617  * Parse a __leave statement.
8618  */
8619 static statement_t *parse_leave(void)
8620 {
8621         statement_t *statement;
8622         if (current_try == NULL) {
8623                 errorf(HERE, "__leave statement not within __try");
8624                 statement = create_invalid_statement();
8625         } else {
8626                 statement = allocate_statement_zero(STATEMENT_LEAVE);
8627
8628                 statement->base.source_position = token.source_position;
8629         }
8630
8631         eat(T___leave);
8632         expect(';');
8633
8634         return statement;
8635 end_error:
8636         return create_invalid_statement();
8637 }
8638
8639 /**
8640  * Check if a given declaration represents a local variable.
8641  */
8642 static bool is_local_var_declaration(const declaration_t *declaration)
8643 {
8644         switch ((storage_class_tag_t) declaration->storage_class) {
8645         case STORAGE_CLASS_AUTO:
8646         case STORAGE_CLASS_REGISTER: {
8647                 const type_t *type = skip_typeref(declaration->type);
8648                 if (is_type_function(type)) {
8649                         return false;
8650                 } else {
8651                         return true;
8652                 }
8653         }
8654         default:
8655                 return false;
8656         }
8657 }
8658
8659 /**
8660  * Check if a given declaration represents a variable.
8661  */
8662 static bool is_var_declaration(const declaration_t *declaration)
8663 {
8664         if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
8665                 return false;
8666
8667         const type_t *type = skip_typeref(declaration->type);
8668         return !is_type_function(type);
8669 }
8670
8671 /**
8672  * Check if a given expression represents a local variable.
8673  */
8674 static bool is_local_variable(const expression_t *expression)
8675 {
8676         if (expression->base.kind != EXPR_REFERENCE) {
8677                 return false;
8678         }
8679         const declaration_t *declaration = expression->reference.declaration;
8680         return is_local_var_declaration(declaration);
8681 }
8682
8683 /**
8684  * Check if a given expression represents a local variable and
8685  * return its declaration then, else return NULL.
8686  */
8687 declaration_t *expr_is_variable(const expression_t *expression)
8688 {
8689         if (expression->base.kind != EXPR_REFERENCE) {
8690                 return NULL;
8691         }
8692         declaration_t *declaration = expression->reference.declaration;
8693         if (is_var_declaration(declaration))
8694                 return declaration;
8695         return NULL;
8696 }
8697
8698 /**
8699  * Parse a return statement.
8700  */
8701 static statement_t *parse_return(void)
8702 {
8703         statement_t *statement          = allocate_statement_zero(STATEMENT_RETURN);
8704         statement->base.source_position = token.source_position;
8705
8706         eat(T_return);
8707
8708         expression_t *return_value = NULL;
8709         if (token.type != ';') {
8710                 return_value = parse_expression();
8711         }
8712         expect(';');
8713
8714         const type_t *const func_type = current_function->type;
8715         assert(is_type_function(func_type));
8716         type_t *const return_type = skip_typeref(func_type->function.return_type);
8717
8718         if (return_value != NULL) {
8719                 type_t *return_value_type = skip_typeref(return_value->base.type);
8720
8721                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)
8722                                 && !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
8723                         warningf(&statement->base.source_position,
8724                                  "'return' with a value, in function returning void");
8725                         return_value = NULL;
8726                 } else {
8727                         assign_error_t error = semantic_assign(return_type, return_value);
8728                         report_assign_error(error, return_type, return_value, "'return'",
8729                                             &statement->base.source_position);
8730                         return_value = create_implicit_cast(return_value, return_type);
8731                 }
8732                 /* check for returning address of a local var */
8733                 if (return_value != NULL &&
8734                                 return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
8735                         const expression_t *expression = return_value->unary.value;
8736                         if (is_local_variable(expression)) {
8737                                 warningf(&statement->base.source_position,
8738                                          "function returns address of local variable");
8739                         }
8740                 }
8741         } else {
8742                 if (!is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
8743                         warningf(&statement->base.source_position,
8744                                  "'return' without value, in function returning non-void");
8745                 }
8746         }
8747         statement->returns.value = return_value;
8748
8749         return statement;
8750 end_error:
8751         return create_invalid_statement();
8752 }
8753
8754 /**
8755  * Parse a declaration statement.
8756  */
8757 static statement_t *parse_declaration_statement(void)
8758 {
8759         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
8760
8761         statement->base.source_position = token.source_position;
8762
8763         declaration_t *before = last_declaration;
8764         parse_declaration(record_declaration);
8765
8766         if (before == NULL) {
8767                 statement->declaration.declarations_begin = scope->declarations;
8768         } else {
8769                 statement->declaration.declarations_begin = before->next;
8770         }
8771         statement->declaration.declarations_end = last_declaration;
8772
8773         return statement;
8774 }
8775
8776 /**
8777  * Parse an expression statement, ie. expr ';'.
8778  */
8779 static statement_t *parse_expression_statement(void)
8780 {
8781         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
8782
8783         statement->base.source_position  = token.source_position;
8784         expression_t *const expr         = parse_expression();
8785         statement->expression.expression = expr;
8786
8787         expect(';');
8788
8789         return statement;
8790 end_error:
8791         return create_invalid_statement();
8792 }
8793
8794 /**
8795  * Parse a microsoft __try { } __finally { } or
8796  * __try{ } __except() { }
8797  */
8798 static statement_t *parse_ms_try_statment(void)
8799 {
8800         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
8801
8802         statement->base.source_position  = token.source_position;
8803         eat(T___try);
8804
8805         ms_try_statement_t *rem = current_try;
8806         current_try = &statement->ms_try;
8807         statement->ms_try.try_statement = parse_compound_statement(false);
8808         current_try = rem;
8809
8810         if (token.type == T___except) {
8811                 eat(T___except);
8812                 expect('(');
8813                 add_anchor_token(')');
8814                 expression_t *const expr = parse_expression();
8815                 type_t       *      type = skip_typeref(expr->base.type);
8816                 if (is_type_integer(type)) {
8817                         type = promote_integer(type);
8818                 } else if (is_type_valid(type)) {
8819                         errorf(&expr->base.source_position,
8820                                "__expect expression is not an integer, but '%T'", type);
8821                         type = type_error_type;
8822                 }
8823                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
8824                 rem_anchor_token(')');
8825                 expect(')');
8826                 statement->ms_try.final_statement = parse_compound_statement(false);
8827         } else if (token.type == T__finally) {
8828                 eat(T___finally);
8829                 statement->ms_try.final_statement = parse_compound_statement(false);
8830         } else {
8831                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
8832                 return create_invalid_statement();
8833         }
8834         return statement;
8835 end_error:
8836         return create_invalid_statement();
8837 }
8838
8839 static statement_t *parse_empty_statement(void)
8840 {
8841         if (warning.empty_statement) {
8842                 warningf(HERE, "statement is empty");
8843         }
8844         eat(';');
8845         return create_empty_statement();
8846 }
8847
8848 /**
8849  * Parse a statement.
8850  * There's also parse_statement() which additionally checks for
8851  * "statement has no effect" warnings
8852  */
8853 static statement_t *intern_parse_statement(void)
8854 {
8855         statement_t *statement = NULL;
8856
8857         /* declaration or statement */
8858         add_anchor_token(';');
8859         switch (token.type) {
8860         case T_IDENTIFIER:
8861                 if (look_ahead(1)->type == ':') {
8862                         statement = parse_label_statement();
8863                 } else if (is_typedef_symbol(token.v.symbol)) {
8864                         statement = parse_declaration_statement();
8865                 } else {
8866                         statement = parse_expression_statement();
8867                 }
8868                 break;
8869
8870         case T___extension__:
8871                 /* This can be a prefix to a declaration or an expression statement.
8872                  * We simply eat it now and parse the rest with tail recursion. */
8873                 do {
8874                         next_token();
8875                 } while (token.type == T___extension__);
8876                 statement = parse_statement();
8877                 break;
8878
8879         DECLARATION_START
8880                 statement = parse_declaration_statement();
8881                 break;
8882
8883         case ';':        statement = parse_empty_statement();         break;
8884         case '{':        statement = parse_compound_statement(false); break;
8885         case T___leave:  statement = parse_leave();                   break;
8886         case T___try:    statement = parse_ms_try_statment();         break;
8887         case T_asm:      statement = parse_asm_statement();           break;
8888         case T_break:    statement = parse_break();                   break;
8889         case T_case:     statement = parse_case_statement();          break;
8890         case T_continue: statement = parse_continue();                break;
8891         case T_default:  statement = parse_default_statement();       break;
8892         case T_do:       statement = parse_do();                      break;
8893         case T_for:      statement = parse_for();                     break;
8894         case T_goto:     statement = parse_goto();                    break;
8895         case T_if:       statement = parse_if ();                     break;
8896         case T_return:   statement = parse_return();                  break;
8897         case T_switch:   statement = parse_switch();                  break;
8898         case T_while:    statement = parse_while();                   break;
8899         default:         statement = parse_expression_statement();    break;
8900         }
8901         rem_anchor_token(';');
8902
8903         assert(statement != NULL
8904                         && statement->base.source_position.input_name != NULL);
8905
8906         return statement;
8907 }
8908
8909 /**
8910  * parse a statement and emits "statement has no effect" warning if needed
8911  * (This is really a wrapper around intern_parse_statement with check for 1
8912  *  single warning. It is needed, because for statement expressions we have
8913  *  to avoid the warning on the last statement)
8914  */
8915 static statement_t *parse_statement(void)
8916 {
8917         statement_t *statement = intern_parse_statement();
8918
8919         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
8920                 expression_t *expression = statement->expression.expression;
8921                 if (!expression_has_effect(expression)) {
8922                         warningf(&expression->base.source_position,
8923                                         "statement has no effect");
8924                 }
8925         }
8926
8927         return statement;
8928 }
8929
8930 /**
8931  * Parse a compound statement.
8932  */
8933 static statement_t *parse_compound_statement(bool inside_expression_statement)
8934 {
8935         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
8936         statement->base.source_position = token.source_position;
8937
8938         PUSH_PARENT(statement);
8939
8940         eat('{');
8941         add_anchor_token('}');
8942
8943         int      top        = environment_top();
8944         scope_t *last_scope = scope;
8945         set_scope(&statement->compound.scope);
8946
8947         statement_t *last_statement = NULL;
8948
8949         bool only_decls_so_far = true;
8950         while (token.type != '}' && token.type != T_EOF) {
8951                 statement_t *sub_statement = intern_parse_statement();
8952                 if (is_invalid_statement(sub_statement)) {
8953                         /* an error occurred. if we are at an anchor, return */
8954                         if (at_anchor())
8955                                 goto end_error;
8956                         continue;
8957                 }
8958
8959                 if (warning.declaration_after_statement) {
8960                         if (sub_statement->kind != STATEMENT_DECLARATION) {
8961                                 only_decls_so_far = false;
8962                         } else if (!only_decls_so_far) {
8963                                 warningf(&sub_statement->base.source_position,
8964                                          "ISO C90 forbids mixed declarations and code");
8965                         }
8966                 }
8967
8968                 if (last_statement != NULL) {
8969                         last_statement->base.next = sub_statement;
8970                 } else {
8971                         statement->compound.statements = sub_statement;
8972                 }
8973
8974                 while (sub_statement->base.next != NULL)
8975                         sub_statement = sub_statement->base.next;
8976
8977                 last_statement = sub_statement;
8978         }
8979
8980         if (token.type == '}') {
8981                 next_token();
8982         } else {
8983                 errorf(&statement->base.source_position,
8984                        "end of file while looking for closing '}'");
8985         }
8986
8987         /* look over all statements again to produce no effect warnings */
8988         if (warning.unused_value) {
8989                 statement_t *sub_statement = statement->compound.statements;
8990                 for( ; sub_statement != NULL; sub_statement = sub_statement->base.next) {
8991                         if (sub_statement->kind != STATEMENT_EXPRESSION)
8992                                 continue;
8993                         /* don't emit a warning for the last expression in an expression
8994                          * statement as it has always an effect */
8995                         if (inside_expression_statement && sub_statement->base.next == NULL)
8996                                 continue;
8997
8998                         expression_t *expression = sub_statement->expression.expression;
8999                         if (!expression_has_effect(expression)) {
9000                                 warningf(&expression->base.source_position,
9001                                          "statement has no effect");
9002                         }
9003                 }
9004         }
9005
9006 end_error:
9007         rem_anchor_token('}');
9008         assert(scope == &statement->compound.scope);
9009         set_scope(last_scope);
9010         environment_pop_to(top);
9011
9012         POP_PARENT;
9013         return statement;
9014 }
9015
9016 /**
9017  * Initialize builtin types.
9018  */
9019 static void initialize_builtin_types(void)
9020 {
9021         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
9022         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
9023         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
9024         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
9025         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
9026         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
9027         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    type_int);
9028         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
9029
9030         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
9031         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
9032         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
9033         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
9034 }
9035
9036 /**
9037  * Check for unused global static functions and variables
9038  */
9039 static void check_unused_globals(void)
9040 {
9041         if (!warning.unused_function && !warning.unused_variable)
9042                 return;
9043
9044         for (const declaration_t *decl = global_scope->declarations; decl != NULL; decl = decl->next) {
9045                 if (decl->used                  ||
9046                     decl->modifiers & DM_UNUSED ||
9047                     decl->modifiers & DM_USED   ||
9048                     decl->storage_class != STORAGE_CLASS_STATIC)
9049                         continue;
9050
9051                 type_t *const type = decl->type;
9052                 const char *s;
9053                 if (is_type_function(skip_typeref(type))) {
9054                         if (!warning.unused_function || decl->is_inline)
9055                                 continue;
9056
9057                         s = (decl->init.statement != NULL ? "defined" : "declared");
9058                 } else {
9059                         if (!warning.unused_variable)
9060                                 continue;
9061
9062                         s = "defined";
9063                 }
9064
9065                 warningf(&decl->source_position, "'%#T' %s but not used",
9066                         type, decl->symbol, s);
9067         }
9068 }
9069
9070 static void parse_global_asm(void)
9071 {
9072         eat(T_asm);
9073         expect('(');
9074
9075         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
9076         statement->base.source_position = token.source_position;
9077         statement->asms.asm_text        = parse_string_literals();
9078         statement->base.next            = unit->global_asm;
9079         unit->global_asm                = statement;
9080
9081         expect(')');
9082         expect(';');
9083
9084 end_error:;
9085 }
9086
9087 /**
9088  * Parse a translation unit.
9089  */
9090 static void parse_translation_unit(void)
9091 {
9092         for (;;) switch (token.type) {
9093                 DECLARATION_START
9094                 case T_IDENTIFIER:
9095                 case T___extension__:
9096                         parse_external_declaration();
9097                         break;
9098
9099                 case T_asm:
9100                         parse_global_asm();
9101                         break;
9102
9103                 case T_EOF:
9104                         return;
9105
9106                 case ';':
9107                         /* TODO error in strict mode */
9108                         warningf(HERE, "stray ';' outside of function");
9109                         next_token();
9110                         break;
9111
9112                 default:
9113                         errorf(HERE, "stray %K outside of function", &token);
9114                         if (token.type == '(' || token.type == '{' || token.type == '[')
9115                                 eat_until_matching_token(token.type);
9116                         next_token();
9117                         break;
9118         }
9119 }
9120
9121 /**
9122  * Parse the input.
9123  *
9124  * @return  the translation unit or NULL if errors occurred.
9125  */
9126 void start_parsing(void)
9127 {
9128         environment_stack = NEW_ARR_F(stack_entry_t, 0);
9129         label_stack       = NEW_ARR_F(stack_entry_t, 0);
9130         diagnostic_count  = 0;
9131         error_count       = 0;
9132         warning_count     = 0;
9133
9134         type_set_output(stderr);
9135         ast_set_output(stderr);
9136
9137         assert(unit == NULL);
9138         unit = allocate_ast_zero(sizeof(unit[0]));
9139
9140         assert(global_scope == NULL);
9141         global_scope = &unit->scope;
9142
9143         assert(scope == NULL);
9144         set_scope(&unit->scope);
9145
9146         initialize_builtin_types();
9147 }
9148
9149 translation_unit_t *finish_parsing(void)
9150 {
9151         assert(scope == &unit->scope);
9152         scope          = NULL;
9153         last_declaration = NULL;
9154
9155         assert(global_scope == &unit->scope);
9156         check_unused_globals();
9157         global_scope = NULL;
9158
9159         DEL_ARR_F(environment_stack);
9160         DEL_ARR_F(label_stack);
9161
9162         translation_unit_t *result = unit;
9163         unit = NULL;
9164         return result;
9165 }
9166
9167 void parse(void)
9168 {
9169         lookahead_bufpos = 0;
9170         for(int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
9171                 next_token();
9172         }
9173         parse_translation_unit();
9174 }
9175
9176 /**
9177  * Initialize the parser.
9178  */
9179 void init_parser(void)
9180 {
9181         if (c_mode & _MS) {
9182                 /* add predefined symbols for extended-decl-modifier */
9183                 sym_align      = symbol_table_insert("align");
9184                 sym_allocate   = symbol_table_insert("allocate");
9185                 sym_dllimport  = symbol_table_insert("dllimport");
9186                 sym_dllexport  = symbol_table_insert("dllexport");
9187                 sym_naked      = symbol_table_insert("naked");
9188                 sym_noinline   = symbol_table_insert("noinline");
9189                 sym_noreturn   = symbol_table_insert("noreturn");
9190                 sym_nothrow    = symbol_table_insert("nothrow");
9191                 sym_novtable   = symbol_table_insert("novtable");
9192                 sym_property   = symbol_table_insert("property");
9193                 sym_get        = symbol_table_insert("get");
9194                 sym_put        = symbol_table_insert("put");
9195                 sym_selectany  = symbol_table_insert("selectany");
9196                 sym_thread     = symbol_table_insert("thread");
9197                 sym_uuid       = symbol_table_insert("uuid");
9198                 sym_deprecated = symbol_table_insert("deprecated");
9199                 sym_restrict   = symbol_table_insert("restrict");
9200                 sym_noalias    = symbol_table_insert("noalias");
9201         }
9202         memset(token_anchor_set, 0, sizeof(token_anchor_set));
9203
9204         init_expression_parsers();
9205         obstack_init(&temp_obst);
9206
9207         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
9208         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
9209 }
9210
9211 /**
9212  * Terminate the parser.
9213  */
9214 void exit_parser(void)
9215 {
9216         obstack_free(&temp_obst, NULL);
9217 }