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                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3278                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3279                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3280                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3281                         | SPECIFIER_INT:
3282                         atomic_type = ATOMIC_TYPE_LONGLONG;
3283                         break;
3284                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3285                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3286                         | SPECIFIER_INT:
3287                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3288                         break;
3289
3290                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3291                         atomic_type = unsigned_int8_type_kind;
3292                         break;
3293
3294                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3295                         atomic_type = unsigned_int16_type_kind;
3296                         break;
3297
3298                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3299                         atomic_type = unsigned_int32_type_kind;
3300                         break;
3301
3302                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3303                         atomic_type = unsigned_int64_type_kind;
3304                         break;
3305
3306                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3307                         atomic_type = unsigned_int128_type_kind;
3308                         break;
3309
3310                 case SPECIFIER_INT8:
3311                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3312                         atomic_type = int8_type_kind;
3313                         break;
3314
3315                 case SPECIFIER_INT16:
3316                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3317                         atomic_type = int16_type_kind;
3318                         break;
3319
3320                 case SPECIFIER_INT32:
3321                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3322                         atomic_type = int32_type_kind;
3323                         break;
3324
3325                 case SPECIFIER_INT64:
3326                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3327                         atomic_type = int64_type_kind;
3328                         break;
3329
3330                 case SPECIFIER_INT128:
3331                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3332                         atomic_type = int128_type_kind;
3333                         break;
3334
3335                 case SPECIFIER_FLOAT:
3336                         atomic_type = ATOMIC_TYPE_FLOAT;
3337                         break;
3338                 case SPECIFIER_DOUBLE:
3339                         atomic_type = ATOMIC_TYPE_DOUBLE;
3340                         break;
3341                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3342                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3343                         break;
3344                 case SPECIFIER_BOOL:
3345                         atomic_type = ATOMIC_TYPE_BOOL;
3346                         break;
3347                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3348                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3349                         atomic_type = ATOMIC_TYPE_FLOAT;
3350                         break;
3351                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3352                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3353                         atomic_type = ATOMIC_TYPE_DOUBLE;
3354                         break;
3355                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3356                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3357                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3358                         break;
3359                 default:
3360                         /* invalid specifier combination, give an error message */
3361                         if (type_specifiers == 0) {
3362                                 if (! strict_mode) {
3363                                         if (warning.implicit_int) {
3364                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3365                                         }
3366                                         atomic_type = ATOMIC_TYPE_INT;
3367                                         break;
3368                                 } else {
3369                                         errorf(HERE, "no type specifiers given in declaration");
3370                                 }
3371                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3372                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3373                                 errorf(HERE, "signed and unsigned specifiers gives");
3374                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3375                                 errorf(HERE, "only integer types can be signed or unsigned");
3376                         } else {
3377                                 errorf(HERE, "multiple datatypes in declaration");
3378                         }
3379                         atomic_type = ATOMIC_TYPE_INVALID;
3380                 }
3381
3382                 if (type_specifiers & SPECIFIER_COMPLEX &&
3383                    atomic_type != ATOMIC_TYPE_INVALID) {
3384                         type                = allocate_type_zero(TYPE_COMPLEX, &builtin_source_position);
3385                         type->complex.akind = atomic_type;
3386                 } else if (type_specifiers & SPECIFIER_IMAGINARY &&
3387                           atomic_type != ATOMIC_TYPE_INVALID) {
3388                         type                  = allocate_type_zero(TYPE_IMAGINARY, &builtin_source_position);
3389                         type->imaginary.akind = atomic_type;
3390                 } else {
3391                         type               = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
3392                         type->atomic.akind = atomic_type;
3393                 }
3394                 newtype = 1;
3395         } else {
3396                 if (type_specifiers != 0) {
3397                         errorf(HERE, "multiple datatypes in declaration");
3398                 }
3399         }
3400
3401         /* FIXME: check type qualifiers here */
3402
3403         type->base.qualifiers = qualifiers;
3404         type->base.modifiers  = modifiers;
3405
3406         type_t *result = typehash_insert(type);
3407         if (newtype && result != type) {
3408                 free_type(type);
3409         }
3410
3411         specifiers->type = result;
3412 end_error:
3413         return;
3414 }
3415
3416 static type_qualifiers_t parse_type_qualifiers(void)
3417 {
3418         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3419
3420         while (true) {
3421                 switch(token.type) {
3422                 /* type qualifiers */
3423                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3424                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3425                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3426                 /* microsoft extended type modifiers */
3427                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3428                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3429                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3430                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3431                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3432
3433                 default:
3434                         return qualifiers;
3435                 }
3436         }
3437 }
3438
3439 static declaration_t *parse_identifier_list(void)
3440 {
3441         declaration_t *declarations     = NULL;
3442         declaration_t *last_declaration = NULL;
3443         do {
3444                 declaration_t *const declaration = allocate_declaration_zero();
3445                 declaration->type            = NULL; /* a K&R parameter list has no types, yet */
3446                 declaration->source_position = token.source_position;
3447                 declaration->symbol          = token.v.symbol;
3448                 next_token();
3449
3450                 if (last_declaration != NULL) {
3451                         last_declaration->next = declaration;
3452                 } else {
3453                         declarations = declaration;
3454                 }
3455                 last_declaration = declaration;
3456
3457                 if (token.type != ',') {
3458                         break;
3459                 }
3460                 next_token();
3461         } while (token.type == T_IDENTIFIER);
3462
3463         return declarations;
3464 }
3465
3466 static type_t *automatic_type_conversion(type_t *orig_type);
3467
3468 static void semantic_parameter(declaration_t *declaration)
3469 {
3470         /* TODO: improve error messages */
3471
3472         if (declaration->declared_storage_class == STORAGE_CLASS_TYPEDEF) {
3473                 errorf(HERE, "typedef not allowed in parameter list");
3474         } else if (declaration->declared_storage_class != STORAGE_CLASS_NONE
3475                         && declaration->declared_storage_class != STORAGE_CLASS_REGISTER) {
3476                 errorf(HERE, "parameter may only have none or register storage class");
3477         }
3478
3479         type_t *const orig_type = declaration->type;
3480         /* §6.7.5.3(7): Array as last part of a parameter type is just syntactic
3481          * sugar.  Turn it into a pointer.
3482          * §6.7.5.3(8): A declaration of a parameter as ``function returning type''
3483          * shall be adjusted to ``pointer to function returning type'', as in 6.3.2.1.
3484          */
3485         type_t *const type = automatic_type_conversion(orig_type);
3486         declaration->type = type;
3487
3488         if (is_type_incomplete(skip_typeref(type))) {
3489                 errorf(HERE, "incomplete type '%T' not allowed for parameter '%Y'",
3490                        orig_type, declaration->symbol);
3491         }
3492 }
3493
3494 static declaration_t *parse_parameter(void)
3495 {
3496         declaration_specifiers_t specifiers;
3497         memset(&specifiers, 0, sizeof(specifiers));
3498
3499         parse_declaration_specifiers(&specifiers);
3500
3501         declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/true);
3502
3503         return declaration;
3504 }
3505
3506 static declaration_t *parse_parameters(function_type_t *type)
3507 {
3508         declaration_t *declarations = NULL;
3509
3510         eat('(');
3511         add_anchor_token(')');
3512         int saved_comma_state = save_and_reset_anchor_state(',');
3513
3514         if (token.type == T_IDENTIFIER) {
3515                 symbol_t *symbol = token.v.symbol;
3516                 if (!is_typedef_symbol(symbol)) {
3517                         type->kr_style_parameters = true;
3518                         declarations = parse_identifier_list();
3519                         goto parameters_finished;
3520                 }
3521         }
3522
3523         if (token.type == ')') {
3524                 type->unspecified_parameters = 1;
3525                 goto parameters_finished;
3526         }
3527
3528         declaration_t        *declaration;
3529         declaration_t        *last_declaration = NULL;
3530         function_parameter_t *parameter;
3531         function_parameter_t *last_parameter = NULL;
3532
3533         while (true) {
3534                 switch(token.type) {
3535                 case T_DOTDOTDOT:
3536                         next_token();
3537                         type->variadic = 1;
3538                         goto parameters_finished;
3539
3540                 case T_IDENTIFIER:
3541                 case T___extension__:
3542                 DECLARATION_START
3543                         declaration = parse_parameter();
3544
3545                         /* func(void) is not a parameter */
3546                         if (last_parameter == NULL
3547                                         && token.type == ')'
3548                                         && declaration->symbol == NULL
3549                                         && skip_typeref(declaration->type) == type_void) {
3550                                 goto parameters_finished;
3551                         }
3552                         semantic_parameter(declaration);
3553
3554                         parameter       = obstack_alloc(type_obst, sizeof(parameter[0]));
3555                         memset(parameter, 0, sizeof(parameter[0]));
3556                         parameter->type = declaration->type;
3557
3558                         if (last_parameter != NULL) {
3559                                 last_declaration->next = declaration;
3560                                 last_parameter->next   = parameter;
3561                         } else {
3562                                 type->parameters = parameter;
3563                                 declarations     = declaration;
3564                         }
3565                         last_parameter   = parameter;
3566                         last_declaration = declaration;
3567                         break;
3568
3569                 default:
3570                         goto parameters_finished;
3571                 }
3572                 if (token.type != ',') {
3573                         goto parameters_finished;
3574                 }
3575                 next_token();
3576         }
3577
3578
3579 parameters_finished:
3580         rem_anchor_token(')');
3581         expect(')');
3582
3583         restore_anchor_state(',', saved_comma_state);
3584         return declarations;
3585
3586 end_error:
3587         restore_anchor_state(',', saved_comma_state);
3588         return NULL;
3589 }
3590
3591 typedef enum construct_type_kind_t {
3592         CONSTRUCT_INVALID,
3593         CONSTRUCT_POINTER,
3594         CONSTRUCT_FUNCTION,
3595         CONSTRUCT_ARRAY
3596 } construct_type_kind_t;
3597
3598 typedef struct construct_type_t construct_type_t;
3599 struct construct_type_t {
3600         construct_type_kind_t  kind;
3601         construct_type_t      *next;
3602 };
3603
3604 typedef struct parsed_pointer_t parsed_pointer_t;
3605 struct parsed_pointer_t {
3606         construct_type_t  construct_type;
3607         type_qualifiers_t type_qualifiers;
3608 };
3609
3610 typedef struct construct_function_type_t construct_function_type_t;
3611 struct construct_function_type_t {
3612         construct_type_t  construct_type;
3613         type_t           *function_type;
3614 };
3615
3616 typedef struct parsed_array_t parsed_array_t;
3617 struct parsed_array_t {
3618         construct_type_t  construct_type;
3619         type_qualifiers_t type_qualifiers;
3620         bool              is_static;
3621         bool              is_variable;
3622         expression_t     *size;
3623 };
3624
3625 typedef struct construct_base_type_t construct_base_type_t;
3626 struct construct_base_type_t {
3627         construct_type_t  construct_type;
3628         type_t           *type;
3629 };
3630
3631 static construct_type_t *parse_pointer_declarator(void)
3632 {
3633         eat('*');
3634
3635         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
3636         memset(pointer, 0, sizeof(pointer[0]));
3637         pointer->construct_type.kind = CONSTRUCT_POINTER;
3638         pointer->type_qualifiers     = parse_type_qualifiers();
3639
3640         return (construct_type_t*) pointer;
3641 }
3642
3643 static construct_type_t *parse_array_declarator(void)
3644 {
3645         eat('[');
3646         add_anchor_token(']');
3647
3648         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
3649         memset(array, 0, sizeof(array[0]));
3650         array->construct_type.kind = CONSTRUCT_ARRAY;
3651
3652         if (token.type == T_static) {
3653                 array->is_static = true;
3654                 next_token();
3655         }
3656
3657         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
3658         if (type_qualifiers != 0) {
3659                 if (token.type == T_static) {
3660                         array->is_static = true;
3661                         next_token();
3662                 }
3663         }
3664         array->type_qualifiers = type_qualifiers;
3665
3666         if (token.type == '*' && look_ahead(1)->type == ']') {
3667                 array->is_variable = true;
3668                 next_token();
3669         } else if (token.type != ']') {
3670                 array->size = parse_assignment_expression();
3671         }
3672
3673         rem_anchor_token(']');
3674         expect(']');
3675
3676         return (construct_type_t*) array;
3677 end_error:
3678         return NULL;
3679 }
3680
3681 static construct_type_t *parse_function_declarator(declaration_t *declaration)
3682 {
3683         type_t *type;
3684         if (declaration != NULL) {
3685                 type = allocate_type_zero(TYPE_FUNCTION, &declaration->source_position);
3686
3687                 unsigned mask = declaration->modifiers & (DM_CDECL|DM_STDCALL|DM_FASTCALL|DM_THISCALL);
3688
3689                 if (mask & (mask-1)) {
3690                         const char *first = NULL, *second = NULL;
3691
3692                         /* more than one calling convention set */
3693                         if (declaration->modifiers & DM_CDECL) {
3694                                 if (first == NULL)       first = "cdecl";
3695                                 else if (second == NULL) second = "cdecl";
3696                         }
3697                         if (declaration->modifiers & DM_STDCALL) {
3698                                 if (first == NULL)       first = "stdcall";
3699                                 else if (second == NULL) second = "stdcall";
3700                         }
3701                         if (declaration->modifiers & DM_FASTCALL) {
3702                                 if (first == NULL)       first = "faslcall";
3703                                 else if (second == NULL) second = "fastcall";
3704                         }
3705                         if (declaration->modifiers & DM_THISCALL) {
3706                                 if (first == NULL)       first = "thiscall";
3707                                 else if (second == NULL) second = "thiscall";
3708                         }
3709                         errorf(&declaration->source_position, "%s and %s attributes are not compatible", first, second);
3710                 }
3711
3712                 if (declaration->modifiers & DM_CDECL)
3713                         type->function.calling_convention = CC_CDECL;
3714                 else if (declaration->modifiers & DM_STDCALL)
3715                         type->function.calling_convention = CC_STDCALL;
3716                 else if (declaration->modifiers & DM_FASTCALL)
3717                         type->function.calling_convention = CC_FASTCALL;
3718                 else if (declaration->modifiers & DM_THISCALL)
3719                         type->function.calling_convention = CC_THISCALL;
3720         } else {
3721                 type = allocate_type_zero(TYPE_FUNCTION, HERE);
3722         }
3723
3724         declaration_t *parameters = parse_parameters(&type->function);
3725         if (declaration != NULL) {
3726                 declaration->scope.declarations = parameters;
3727         }
3728
3729         construct_function_type_t *construct_function_type =
3730                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
3731         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
3732         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
3733         construct_function_type->function_type       = type;
3734
3735         return &construct_function_type->construct_type;
3736 }
3737
3738 static void fix_declaration_type(declaration_t *declaration)
3739 {
3740         decl_modifiers_t declaration_modifiers = declaration->modifiers;
3741         type_modifiers_t type_modifiers        = declaration->type->base.modifiers;
3742
3743         if (declaration_modifiers & DM_TRANSPARENT_UNION)
3744                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3745
3746         if (declaration->type->base.modifiers == type_modifiers)
3747                 return;
3748
3749         type_t *copy = duplicate_type(declaration->type);
3750         copy->base.modifiers = type_modifiers;
3751
3752         type_t *result = typehash_insert(copy);
3753         if (result != copy) {
3754                 obstack_free(type_obst, copy);
3755         }
3756
3757         declaration->type = result;
3758 }
3759
3760 static construct_type_t *parse_inner_declarator(declaration_t *declaration,
3761                 bool may_be_abstract)
3762 {
3763         /* construct a single linked list of construct_type_t's which describe
3764          * how to construct the final declarator type */
3765         construct_type_t *first = NULL;
3766         construct_type_t *last  = NULL;
3767         gnu_attribute_t  *attributes = NULL;
3768
3769         declaration->modifiers |= parse_attributes(&attributes);
3770
3771         /* pointers */
3772         while (token.type == '*') {
3773                 construct_type_t *type = parse_pointer_declarator();
3774
3775                 if (last == NULL) {
3776                         first = type;
3777                         last  = type;
3778                 } else {
3779                         last->next = type;
3780                         last       = type;
3781                 }
3782
3783                 /* TODO: find out if this is correct */
3784                 declaration->modifiers |= parse_attributes(&attributes);
3785         }
3786
3787         construct_type_t *inner_types = NULL;
3788
3789         switch(token.type) {
3790         case T_IDENTIFIER:
3791                 if (declaration == NULL) {
3792                         errorf(HERE, "no identifier expected in typename");
3793                 } else {
3794                         declaration->symbol          = token.v.symbol;
3795                         declaration->source_position = token.source_position;
3796                 }
3797                 next_token();
3798                 break;
3799         case '(':
3800                 next_token();
3801                 add_anchor_token(')');
3802                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
3803                 rem_anchor_token(')');
3804                 expect(')');
3805                 break;
3806         default:
3807                 if (may_be_abstract)
3808                         break;
3809                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
3810                 /* avoid a loop in the outermost scope, because eat_statement doesn't
3811                  * eat '}' */
3812                 if (token.type == '}' && current_function == NULL) {
3813                         next_token();
3814                 } else {
3815                         eat_statement();
3816                 }
3817                 return NULL;
3818         }
3819
3820         construct_type_t *p = last;
3821
3822         while(true) {
3823                 construct_type_t *type;
3824                 switch(token.type) {
3825                 case '(':
3826                         type = parse_function_declarator(declaration);
3827                         break;
3828                 case '[':
3829                         type = parse_array_declarator();
3830                         break;
3831                 default:
3832                         goto declarator_finished;
3833                 }
3834
3835                 /* insert in the middle of the list (behind p) */
3836                 if (p != NULL) {
3837                         type->next = p->next;
3838                         p->next    = type;
3839                 } else {
3840                         type->next = first;
3841                         first      = type;
3842                 }
3843                 if (last == p) {
3844                         last = type;
3845                 }
3846         }
3847
3848 declarator_finished:
3849         /* append inner_types at the end of the list, we don't to set last anymore
3850          * as it's not needed anymore */
3851         if (last == NULL) {
3852                 assert(first == NULL);
3853                 first = inner_types;
3854         } else {
3855                 last->next = inner_types;
3856         }
3857
3858         return first;
3859 end_error:
3860         return NULL;
3861 }
3862
3863 static void parse_declaration_attributes(declaration_t *declaration)
3864 {
3865         gnu_attribute_t  *attributes = NULL;
3866         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
3867
3868         if (declaration == NULL)
3869                 return;
3870
3871         declaration->modifiers |= modifiers;
3872         /* check if we have these stupid mode attributes... */
3873         type_t *old_type = declaration->type;
3874         if (old_type == NULL)
3875                 return;
3876
3877         gnu_attribute_t *attribute = attributes;
3878         for ( ; attribute != NULL; attribute = attribute->next) {
3879                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
3880                         continue;
3881
3882                 atomic_type_kind_t  akind = attribute->u.akind;
3883                 if (!is_type_signed(old_type)) {
3884                         switch(akind) {
3885                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
3886                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
3887                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
3888                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
3889                         default:
3890                                 panic("invalid akind in mode attribute");
3891                         }
3892                 }
3893                 declaration->type
3894                         = make_atomic_type(akind, old_type->base.qualifiers);
3895         }
3896 }
3897
3898 static type_t *construct_declarator_type(construct_type_t *construct_list,
3899                                          type_t *type)
3900 {
3901         construct_type_t *iter = construct_list;
3902         for( ; iter != NULL; iter = iter->next) {
3903                 switch(iter->kind) {
3904                 case CONSTRUCT_INVALID:
3905                         internal_errorf(HERE, "invalid type construction found");
3906                 case CONSTRUCT_FUNCTION: {
3907                         construct_function_type_t *construct_function_type
3908                                 = (construct_function_type_t*) iter;
3909
3910                         type_t *function_type = construct_function_type->function_type;
3911
3912                         function_type->function.return_type = type;
3913
3914                         type_t *skipped_return_type = skip_typeref(type);
3915                         if (is_type_function(skipped_return_type)) {
3916                                 errorf(HERE, "function returning function is not allowed");
3917                                 type = type_error_type;
3918                         } else if (is_type_array(skipped_return_type)) {
3919                                 errorf(HERE, "function returning array is not allowed");
3920                                 type = type_error_type;
3921                         } else {
3922                                 type = function_type;
3923                         }
3924                         break;
3925                 }
3926
3927                 case CONSTRUCT_POINTER: {
3928                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
3929                         type_t           *pointer_type   = allocate_type_zero(TYPE_POINTER, &null_position);
3930                         pointer_type->pointer.points_to  = type;
3931                         pointer_type->base.qualifiers    = parsed_pointer->type_qualifiers;
3932
3933                         type = pointer_type;
3934                         break;
3935                 }
3936
3937                 case CONSTRUCT_ARRAY: {
3938                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
3939                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY, &null_position);
3940
3941                         expression_t *size_expression = parsed_array->size;
3942                         if (size_expression != NULL) {
3943                                 size_expression
3944                                         = create_implicit_cast(size_expression, type_size_t);
3945                         }
3946
3947                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
3948                         array_type->array.element_type    = type;
3949                         array_type->array.is_static       = parsed_array->is_static;
3950                         array_type->array.is_variable     = parsed_array->is_variable;
3951                         array_type->array.size_expression = size_expression;
3952
3953                         if (size_expression != NULL) {
3954                                 if (is_constant_expression(size_expression)) {
3955                                         array_type->array.size_constant = true;
3956                                         array_type->array.size
3957                                                 = fold_constant(size_expression);
3958                                 } else {
3959                                         array_type->array.is_vla = true;
3960                                 }
3961                         }
3962
3963                         type_t *skipped_type = skip_typeref(type);
3964                         if (is_type_atomic(skipped_type, ATOMIC_TYPE_VOID)) {
3965                                 errorf(HERE, "array of void is not allowed");
3966                                 type = type_error_type;
3967                         } else {
3968                                 type = array_type;
3969                         }
3970                         break;
3971                 }
3972                 }
3973
3974                 type_t *hashed_type = typehash_insert(type);
3975                 if (hashed_type != type) {
3976                         /* the function type was constructed earlier freeing it here will
3977                          * destroy other types... */
3978                         if (iter->kind != CONSTRUCT_FUNCTION) {
3979                                 free_type(type);
3980                         }
3981                         type = hashed_type;
3982                 }
3983         }
3984
3985         return type;
3986 }
3987
3988 static declaration_t *parse_declarator(
3989                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
3990 {
3991         declaration_t *const declaration    = allocate_declaration_zero();
3992         declaration->declared_storage_class = specifiers->declared_storage_class;
3993         declaration->modifiers              = specifiers->modifiers;
3994         declaration->deprecated_string      = specifiers->deprecated_string;
3995         declaration->get_property_sym       = specifiers->get_property_sym;
3996         declaration->put_property_sym       = specifiers->put_property_sym;
3997         declaration->is_inline              = specifiers->is_inline;
3998
3999         declaration->storage_class          = specifiers->declared_storage_class;
4000         if (declaration->storage_class == STORAGE_CLASS_NONE
4001                         && scope != global_scope) {
4002                 declaration->storage_class = STORAGE_CLASS_AUTO;
4003         }
4004
4005         if (specifiers->alignment != 0) {
4006                 /* TODO: add checks here */
4007                 declaration->alignment = specifiers->alignment;
4008         }
4009
4010         construct_type_t *construct_type
4011                 = parse_inner_declarator(declaration, may_be_abstract);
4012         type_t *const type = specifiers->type;
4013         declaration->type = construct_declarator_type(construct_type, type);
4014
4015         parse_declaration_attributes(declaration);
4016
4017         fix_declaration_type(declaration);
4018
4019         if (construct_type != NULL) {
4020                 obstack_free(&temp_obst, construct_type);
4021         }
4022
4023         return declaration;
4024 }
4025
4026 static type_t *parse_abstract_declarator(type_t *base_type)
4027 {
4028         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4029
4030         type_t *result = construct_declarator_type(construct_type, base_type);
4031         if (construct_type != NULL) {
4032                 obstack_free(&temp_obst, construct_type);
4033         }
4034
4035         return result;
4036 }
4037
4038 static declaration_t *append_declaration(declaration_t* const declaration)
4039 {
4040         if (last_declaration != NULL) {
4041                 last_declaration->next = declaration;
4042         } else {
4043                 scope->declarations = declaration;
4044         }
4045         last_declaration = declaration;
4046         return declaration;
4047 }
4048
4049 /**
4050  * Check if the declaration of main is suspicious.  main should be a
4051  * function with external linkage, returning int, taking either zero
4052  * arguments, two, or three arguments of appropriate types, ie.
4053  *
4054  * int main([ int argc, char **argv [, char **env ] ]).
4055  *
4056  * @param decl    the declaration to check
4057  * @param type    the function type of the declaration
4058  */
4059 static void check_type_of_main(const declaration_t *const decl, const function_type_t *const func_type)
4060 {
4061         if (decl->storage_class == STORAGE_CLASS_STATIC) {
4062                 warningf(&decl->source_position,
4063                          "'main' is normally a non-static function");
4064         }
4065         if (skip_typeref(func_type->return_type) != type_int) {
4066                 warningf(&decl->source_position,
4067                          "return type of 'main' should be 'int', but is '%T'",
4068                          func_type->return_type);
4069         }
4070         const function_parameter_t *parm = func_type->parameters;
4071         if (parm != NULL) {
4072                 type_t *const first_type = parm->type;
4073                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4074                         warningf(&decl->source_position,
4075                                  "first argument of 'main' should be 'int', but is '%T'", first_type);
4076                 }
4077                 parm = parm->next;
4078                 if (parm != NULL) {
4079                         type_t *const second_type = parm->type;
4080                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4081                                 warningf(&decl->source_position,
4082                                          "second argument of 'main' should be 'char**', but is '%T'", second_type);
4083                         }
4084                         parm = parm->next;
4085                         if (parm != NULL) {
4086                                 type_t *const third_type = parm->type;
4087                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4088                                         warningf(&decl->source_position,
4089                                                  "third argument of 'main' should be 'char**', but is '%T'", third_type);
4090                                 }
4091                                 parm = parm->next;
4092                                 if (parm != NULL)
4093                                         goto warn_arg_count;
4094                         }
4095                 } else {
4096 warn_arg_count:
4097                         warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
4098                 }
4099         }
4100 }
4101
4102 /**
4103  * Check if a symbol is the equal to "main".
4104  */
4105 static bool is_sym_main(const symbol_t *const sym)
4106 {
4107         return strcmp(sym->string, "main") == 0;
4108 }
4109
4110 static declaration_t *internal_record_declaration(
4111         declaration_t *const declaration,
4112         const bool is_definition)
4113 {
4114         const symbol_t *const symbol  = declaration->symbol;
4115         const namespace_t     namespc = (namespace_t)declaration->namespc;
4116
4117         assert(declaration->symbol != NULL);
4118         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4119
4120         type_t *const orig_type = declaration->type;
4121         type_t *const type      = skip_typeref(orig_type);
4122         if (is_type_function(type) &&
4123                         type->function.unspecified_parameters &&
4124                         warning.strict_prototypes &&
4125                         previous_declaration == NULL) {
4126                 warningf(&declaration->source_position,
4127                          "function declaration '%#T' is not a prototype",
4128                          orig_type, declaration->symbol);
4129         }
4130
4131         if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
4132                 check_type_of_main(declaration, &type->function);
4133         }
4134
4135         assert(declaration != previous_declaration);
4136         if (previous_declaration != NULL
4137                         && previous_declaration->parent_scope == scope) {
4138                 /* can happen for K&R style declarations */
4139                 if (previous_declaration->type == NULL) {
4140                         previous_declaration->type = declaration->type;
4141                 }
4142
4143                 const type_t *prev_type = skip_typeref(previous_declaration->type);
4144                 if (!types_compatible(type, prev_type)) {
4145                         errorf(&declaration->source_position,
4146                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
4147                                    orig_type, symbol, previous_declaration->type, symbol,
4148                                    &previous_declaration->source_position);
4149                 } else {
4150                         unsigned old_storage_class = previous_declaration->storage_class;
4151                         if (old_storage_class == STORAGE_CLASS_ENUM_ENTRY) {
4152                                 errorf(&declaration->source_position,
4153                                            "redeclaration of enum entry '%Y' (declared %P)",
4154                                            symbol, &previous_declaration->source_position);
4155                                 return previous_declaration;
4156                         }
4157
4158                         if (warning.redundant_decls                                     &&
4159                             is_definition                                               &&
4160                             previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
4161                             !(previous_declaration->modifiers & DM_USED)                &&
4162                             !previous_declaration->used) {
4163                                 warningf(&previous_declaration->source_position,
4164                                          "unnecessary static forward declaration for '%#T'",
4165                                          previous_declaration->type, symbol);
4166                         }
4167
4168                         unsigned new_storage_class = declaration->storage_class;
4169
4170                         if (is_type_incomplete(prev_type)) {
4171                                 previous_declaration->type = type;
4172                                 prev_type                  = type;
4173                         }
4174
4175                         /* pretend no storage class means extern for function
4176                          * declarations (except if the previous declaration is neither
4177                          * none nor extern) */
4178                         if (is_type_function(type)) {
4179                                 if (prev_type->function.unspecified_parameters) {
4180                                         previous_declaration->type = type;
4181                                         prev_type                  = type;
4182                                 }
4183
4184                                 switch (old_storage_class) {
4185                                 case STORAGE_CLASS_NONE:
4186                                         old_storage_class = STORAGE_CLASS_EXTERN;
4187                                         /* FALLTHROUGH */
4188
4189                                 case STORAGE_CLASS_EXTERN:
4190                                         if (is_definition) {
4191                                                 if (warning.missing_prototypes &&
4192                                                     prev_type->function.unspecified_parameters &&
4193                                                     !is_sym_main(symbol)) {
4194                                                         warningf(&declaration->source_position,
4195                                                                          "no previous prototype for '%#T'",
4196                                                                          orig_type, symbol);
4197                                                 }
4198                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4199                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4200                                         }
4201                                         break;
4202
4203                                 default:
4204                                         break;
4205                                 }
4206                         }
4207
4208                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
4209                                         new_storage_class == STORAGE_CLASS_EXTERN) {
4210 warn_redundant_declaration:
4211                                 if (!is_definition          &&
4212                                     warning.redundant_decls &&
4213                                     strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
4214                                         warningf(&declaration->source_position,
4215                                                  "redundant declaration for '%Y' (declared %P)",
4216                                                  symbol, &previous_declaration->source_position);
4217                                 }
4218                         } else if (current_function == NULL) {
4219                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
4220                                     new_storage_class == STORAGE_CLASS_STATIC) {
4221                                         errorf(&declaration->source_position,
4222                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
4223                                                symbol, &previous_declaration->source_position);
4224                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4225                                         previous_declaration->storage_class          = STORAGE_CLASS_NONE;
4226                                         previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
4227                                 } else {
4228                                         goto warn_redundant_declaration;
4229                                 }
4230                         } else if (old_storage_class == new_storage_class) {
4231                                 errorf(&declaration->source_position,
4232                                        "redeclaration of '%Y' (declared %P)",
4233                                        symbol, &previous_declaration->source_position);
4234                         } else {
4235                                 errorf(&declaration->source_position,
4236                                        "redeclaration of '%Y' with different linkage (declared %P)",
4237                                        symbol, &previous_declaration->source_position);
4238                         }
4239                 }
4240
4241                 previous_declaration->modifiers |= declaration->modifiers;
4242                 previous_declaration->is_inline |= declaration->is_inline;
4243                 return previous_declaration;
4244         } else if (is_type_function(type)) {
4245                 if (is_definition &&
4246                     declaration->storage_class != STORAGE_CLASS_STATIC) {
4247                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4248                                 warningf(&declaration->source_position,
4249                                          "no previous prototype for '%#T'", orig_type, symbol);
4250                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4251                                 warningf(&declaration->source_position,
4252                                          "no previous declaration for '%#T'", orig_type,
4253                                          symbol);
4254                         }
4255                 }
4256         } else {
4257                 if (warning.missing_declarations &&
4258                     scope == global_scope && (
4259                       declaration->storage_class == STORAGE_CLASS_NONE ||
4260                       declaration->storage_class == STORAGE_CLASS_THREAD
4261                     )) {
4262                         warningf(&declaration->source_position,
4263                                  "no previous declaration for '%#T'", orig_type, symbol);
4264                 }
4265         }
4266
4267         assert(declaration->parent_scope == NULL);
4268         assert(scope != NULL);
4269
4270         declaration->parent_scope = scope;
4271
4272         environment_push(declaration);
4273         return append_declaration(declaration);
4274 }
4275
4276 static declaration_t *record_declaration(declaration_t *declaration)
4277 {
4278         return internal_record_declaration(declaration, false);
4279 }
4280
4281 static declaration_t *record_definition(declaration_t *declaration)
4282 {
4283         return internal_record_declaration(declaration, true);
4284 }
4285
4286 static void parser_error_multiple_definition(declaration_t *declaration,
4287                 const source_position_t *source_position)
4288 {
4289         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
4290                declaration->symbol, &declaration->source_position);
4291 }
4292
4293 static bool is_declaration_specifier(const token_t *token,
4294                                      bool only_specifiers_qualifiers)
4295 {
4296         switch(token->type) {
4297                 TYPE_SPECIFIERS
4298                 TYPE_QUALIFIERS
4299                         return true;
4300                 case T_IDENTIFIER:
4301                         return is_typedef_symbol(token->v.symbol);
4302
4303                 case T___extension__:
4304                 STORAGE_CLASSES
4305                         return !only_specifiers_qualifiers;
4306
4307                 default:
4308                         return false;
4309         }
4310 }
4311
4312 static void parse_init_declarator_rest(declaration_t *declaration)
4313 {
4314         eat('=');
4315
4316         type_t *orig_type = declaration->type;
4317         type_t *type      = skip_typeref(orig_type);
4318
4319         if (declaration->init.initializer != NULL) {
4320                 parser_error_multiple_definition(declaration, HERE);
4321         }
4322
4323         bool must_be_constant = false;
4324         if (declaration->storage_class == STORAGE_CLASS_STATIC
4325                         || declaration->storage_class == STORAGE_CLASS_THREAD_STATIC
4326                         || declaration->parent_scope == global_scope) {
4327                 must_be_constant = true;
4328         }
4329
4330         parse_initializer_env_t env;
4331         env.type             = orig_type;
4332         env.must_be_constant = must_be_constant;
4333         env.declaration      = declaration;
4334
4335         initializer_t *initializer = parse_initializer(&env);
4336
4337         if (env.type != orig_type) {
4338                 orig_type         = env.type;
4339                 type              = skip_typeref(orig_type);
4340                 declaration->type = env.type;
4341         }
4342
4343         if (is_type_function(type)) {
4344                 errorf(&declaration->source_position,
4345                        "initializers not allowed for function types at declator '%Y' (type '%T')",
4346                        declaration->symbol, orig_type);
4347         } else {
4348                 declaration->init.initializer = initializer;
4349         }
4350 }
4351
4352 /* parse rest of a declaration without any declarator */
4353 static void parse_anonymous_declaration_rest(
4354                 const declaration_specifiers_t *specifiers,
4355                 parsed_declaration_func finished_declaration)
4356 {
4357         eat(';');
4358
4359         declaration_t *const declaration    = allocate_declaration_zero();
4360         declaration->type                   = specifiers->type;
4361         declaration->declared_storage_class = specifiers->declared_storage_class;
4362         declaration->source_position        = specifiers->source_position;
4363         declaration->modifiers              = specifiers->modifiers;
4364
4365         if (declaration->declared_storage_class != STORAGE_CLASS_NONE) {
4366                 warningf(&declaration->source_position,
4367                          "useless storage class in empty declaration");
4368         }
4369         declaration->storage_class = STORAGE_CLASS_NONE;
4370
4371         type_t *type = declaration->type;
4372         switch (type->kind) {
4373                 case TYPE_COMPOUND_STRUCT:
4374                 case TYPE_COMPOUND_UNION: {
4375                         if (type->compound.declaration->symbol == NULL) {
4376                                 warningf(&declaration->source_position,
4377                                          "unnamed struct/union that defines no instances");
4378                         }
4379                         break;
4380                 }
4381
4382                 case TYPE_ENUM:
4383                         break;
4384
4385                 default:
4386                         warningf(&declaration->source_position, "empty declaration");
4387                         break;
4388         }
4389
4390         finished_declaration(declaration);
4391 }
4392
4393 static void parse_declaration_rest(declaration_t *ndeclaration,
4394                 const declaration_specifiers_t *specifiers,
4395                 parsed_declaration_func finished_declaration)
4396 {
4397         add_anchor_token(';');
4398         add_anchor_token('=');
4399         add_anchor_token(',');
4400         while(true) {
4401                 declaration_t *declaration = finished_declaration(ndeclaration);
4402
4403                 type_t *orig_type = declaration->type;
4404                 type_t *type      = skip_typeref(orig_type);
4405
4406                 if (type->kind != TYPE_FUNCTION &&
4407                     declaration->is_inline &&
4408                     is_type_valid(type)) {
4409                         warningf(&declaration->source_position,
4410                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
4411                 }
4412
4413                 if (token.type == '=') {
4414                         parse_init_declarator_rest(declaration);
4415                 }
4416
4417                 if (token.type != ',')
4418                         break;
4419                 eat(',');
4420
4421                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
4422         }
4423         expect(';');
4424
4425 end_error:
4426         rem_anchor_token(';');
4427         rem_anchor_token('=');
4428         rem_anchor_token(',');
4429 }
4430
4431 static declaration_t *finished_kr_declaration(declaration_t *declaration)
4432 {
4433         symbol_t *symbol  = declaration->symbol;
4434         if (symbol == NULL) {
4435                 errorf(HERE, "anonymous declaration not valid as function parameter");
4436                 return declaration;
4437         }
4438         namespace_t namespc = (namespace_t) declaration->namespc;
4439         if (namespc != NAMESPACE_NORMAL) {
4440                 return record_declaration(declaration);
4441         }
4442
4443         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4444         if (previous_declaration == NULL ||
4445                         previous_declaration->parent_scope != scope) {
4446                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4447                        symbol);
4448                 return declaration;
4449         }
4450
4451         if (previous_declaration->type == NULL) {
4452                 previous_declaration->type          = declaration->type;
4453                 previous_declaration->declared_storage_class = declaration->declared_storage_class;
4454                 previous_declaration->storage_class = declaration->storage_class;
4455                 previous_declaration->parent_scope  = scope;
4456                 return previous_declaration;
4457         } else {
4458                 return record_declaration(declaration);
4459         }
4460 }
4461
4462 static void parse_declaration(parsed_declaration_func finished_declaration)
4463 {
4464         declaration_specifiers_t specifiers;
4465         memset(&specifiers, 0, sizeof(specifiers));
4466         parse_declaration_specifiers(&specifiers);
4467
4468         if (token.type == ';') {
4469                 parse_anonymous_declaration_rest(&specifiers, append_declaration);
4470         } else {
4471                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
4472                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
4473         }
4474 }
4475
4476 static type_t *get_default_promoted_type(type_t *orig_type)
4477 {
4478         type_t *result = orig_type;
4479
4480         type_t *type = skip_typeref(orig_type);
4481         if (is_type_integer(type)) {
4482                 result = promote_integer(type);
4483         } else if (type == type_float) {
4484                 result = type_double;
4485         }
4486
4487         return result;
4488 }
4489
4490 static void parse_kr_declaration_list(declaration_t *declaration)
4491 {
4492         type_t *type = skip_typeref(declaration->type);
4493         if (!is_type_function(type))
4494                 return;
4495
4496         if (!type->function.kr_style_parameters)
4497                 return;
4498
4499         /* push function parameters */
4500         int       top        = environment_top();
4501         scope_t  *last_scope = scope;
4502         set_scope(&declaration->scope);
4503
4504         declaration_t *parameter = declaration->scope.declarations;
4505         for ( ; parameter != NULL; parameter = parameter->next) {
4506                 assert(parameter->parent_scope == NULL);
4507                 parameter->parent_scope = scope;
4508                 environment_push(parameter);
4509         }
4510
4511         /* parse declaration list */
4512         while (is_declaration_specifier(&token, false)) {
4513                 parse_declaration(finished_kr_declaration);
4514         }
4515
4516         /* pop function parameters */
4517         assert(scope == &declaration->scope);
4518         set_scope(last_scope);
4519         environment_pop_to(top);
4520
4521         /* update function type */
4522         type_t *new_type = duplicate_type(type);
4523
4524         function_parameter_t *parameters     = NULL;
4525         function_parameter_t *last_parameter = NULL;
4526
4527         declaration_t *parameter_declaration = declaration->scope.declarations;
4528         for( ; parameter_declaration != NULL;
4529                         parameter_declaration = parameter_declaration->next) {
4530                 type_t *parameter_type = parameter_declaration->type;
4531                 if (parameter_type == NULL) {
4532                         if (strict_mode) {
4533                                 errorf(HERE, "no type specified for function parameter '%Y'",
4534                                        parameter_declaration->symbol);
4535                         } else {
4536                                 if (warning.implicit_int) {
4537                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
4538                                                 parameter_declaration->symbol);
4539                                 }
4540                                 parameter_type              = type_int;
4541                                 parameter_declaration->type = parameter_type;
4542                         }
4543                 }
4544
4545                 semantic_parameter(parameter_declaration);
4546                 parameter_type = parameter_declaration->type;
4547
4548                 /*
4549                  * we need the default promoted types for the function type
4550                  */
4551                 parameter_type = get_default_promoted_type(parameter_type);
4552
4553                 function_parameter_t *function_parameter
4554                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
4555                 memset(function_parameter, 0, sizeof(function_parameter[0]));
4556
4557                 function_parameter->type = parameter_type;
4558                 if (last_parameter != NULL) {
4559                         last_parameter->next = function_parameter;
4560                 } else {
4561                         parameters = function_parameter;
4562                 }
4563                 last_parameter = function_parameter;
4564         }
4565
4566         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
4567          * prototype */
4568         new_type->function.parameters             = parameters;
4569         new_type->function.unspecified_parameters = true;
4570
4571         type = typehash_insert(new_type);
4572         if (type != new_type) {
4573                 obstack_free(type_obst, new_type);
4574         }
4575
4576         declaration->type = type;
4577 }
4578
4579 static bool first_err = true;
4580
4581 /**
4582  * When called with first_err set, prints the name of the current function,
4583  * else does noting.
4584  */
4585 static void print_in_function(void)
4586 {
4587         if (first_err) {
4588                 first_err = false;
4589                 diagnosticf("%s: In function '%Y':\n",
4590                         current_function->source_position.input_name,
4591                         current_function->symbol);
4592         }
4593 }
4594
4595 /**
4596  * Check if all labels are defined in the current function.
4597  * Check if all labels are used in the current function.
4598  */
4599 static void check_labels(void)
4600 {
4601         for (const goto_statement_t *goto_statement = goto_first;
4602             goto_statement != NULL;
4603             goto_statement = goto_statement->next) {
4604                 declaration_t *label = goto_statement->label;
4605
4606                 label->used = true;
4607                 if (label->source_position.input_name == NULL) {
4608                         print_in_function();
4609                         errorf(&goto_statement->base.source_position,
4610                                "label '%Y' used but not defined", label->symbol);
4611                  }
4612         }
4613         goto_first = goto_last = NULL;
4614
4615         if (warning.unused_label) {
4616                 for (const label_statement_t *label_statement = label_first;
4617                          label_statement != NULL;
4618                          label_statement = label_statement->next) {
4619                         const declaration_t *label = label_statement->label;
4620
4621                         if (! label->used) {
4622                                 print_in_function();
4623                                 warningf(&label_statement->base.source_position,
4624                                         "label '%Y' defined but not used", label->symbol);
4625                         }
4626                 }
4627         }
4628         label_first = label_last = NULL;
4629 }
4630
4631 /**
4632  * Check declarations of current_function for unused entities.
4633  */
4634 static void check_declarations(void)
4635 {
4636         if (warning.unused_parameter) {
4637                 const scope_t *scope = &current_function->scope;
4638
4639                 const declaration_t *parameter = scope->declarations;
4640                 for (; parameter != NULL; parameter = parameter->next) {
4641                         if (! parameter->used) {
4642                                 print_in_function();
4643                                 warningf(&parameter->source_position,
4644                                          "unused parameter '%Y'", parameter->symbol);
4645                         }
4646                 }
4647         }
4648         if (warning.unused_variable) {
4649         }
4650 }
4651
4652 static int determine_truth(expression_t const* const cond)
4653 {
4654         return
4655                 !is_constant_expression(cond) ? 0 :
4656                 fold_constant(cond) != 0      ? 1 :
4657                 -1;
4658 }
4659
4660 static void check_reachable(statement_t *const stmt)
4661 {
4662         if (stmt->base.reachable)
4663                 return;
4664         if (stmt->kind != STATEMENT_DO_WHILE)
4665                 stmt->base.reachable = true;
4666
4667         statement_t *last = stmt;
4668         statement_t *next;
4669         switch (stmt->kind) {
4670                 case STATEMENT_INVALID:
4671                 case STATEMENT_EMPTY:
4672                 case STATEMENT_DECLARATION:
4673                 case STATEMENT_ASM:
4674                         next = stmt->base.next;
4675                         break;
4676
4677                 case STATEMENT_COMPOUND:
4678                         next = stmt->compound.statements;
4679                         break;
4680
4681                 case STATEMENT_RETURN:
4682                         return;
4683
4684                 case STATEMENT_IF: {
4685                         if_statement_t const* const ifs = &stmt->ifs;
4686                         int            const        val = determine_truth(ifs->condition);
4687
4688                         if (val >= 0)
4689                                 check_reachable(ifs->true_statement);
4690
4691                         if (val > 0)
4692                                 return;
4693
4694                         if (ifs->false_statement != NULL) {
4695                                 check_reachable(ifs->false_statement);
4696                                 return;
4697                         }
4698
4699                         next = stmt->base.next;
4700                         break;
4701                 }
4702
4703                 case STATEMENT_SWITCH: {
4704                         switch_statement_t const *const switchs = &stmt->switchs;
4705                         expression_t       const *const expr    = switchs->expression;
4706
4707                         if (is_constant_expression(expr)) {
4708                                 long                    const val      = fold_constant(expr);
4709                                 case_label_statement_t *      defaults = NULL;
4710                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4711                                         if (i->expression == NULL) {
4712                                                 defaults = i;
4713                                                 continue;
4714                                         }
4715
4716                                         expression_t *const case_expr = i->expression;
4717                                         if (is_constant_expression(case_expr) &&
4718                                             fold_constant(case_expr) == val) {
4719                                                 check_reachable((statement_t*)i);
4720                                                 return;
4721                                         }
4722                                 }
4723
4724                                 if (defaults != NULL) {
4725                                         check_reachable((statement_t*)defaults);
4726                                         return;
4727                                 }
4728                         } else {
4729                                 bool has_default = false;
4730                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4731                                         if (i->expression == NULL)
4732                                                 has_default = true;
4733
4734                                         check_reachable((statement_t*)i);
4735                                 }
4736
4737                                 if (has_default)
4738                                         return;
4739                         }
4740
4741                         next = stmt->base.next;
4742                         break;
4743                 }
4744
4745                 case STATEMENT_EXPRESSION: {
4746                         /* Check for noreturn function call */
4747                         expression_t const *const expr = stmt->expression.expression;
4748                         if (expr->kind == EXPR_CALL) {
4749                                 expression_t const *const func = expr->call.function;
4750                                 if (func->kind == EXPR_REFERENCE) {
4751                                         declaration_t const *const decl = func->reference.declaration;
4752                                         if (decl != NULL && decl->modifiers & DM_NORETURN) {
4753                                                 return;
4754                                         }
4755                                 }
4756                         }
4757
4758                         next = stmt->base.next;
4759                         break;
4760                 }
4761
4762                 case STATEMENT_CONTINUE: {
4763                         statement_t *parent = stmt;
4764                         for (;;) {
4765                                 parent = parent->base.parent;
4766                                 if (parent == NULL) /* continue not within loop */
4767                                         return;
4768
4769                                 next = parent;
4770                                 switch (parent->kind) {
4771                                         case STATEMENT_WHILE:    goto continue_while;
4772                                         case STATEMENT_DO_WHILE: goto continue_do_while;
4773                                         case STATEMENT_FOR:      goto continue_for;
4774
4775                                         default: break;
4776                                 }
4777                         }
4778                 }
4779
4780                 case STATEMENT_BREAK: {
4781                         statement_t *parent = stmt;
4782                         for (;;) {
4783                                 parent = parent->base.parent;
4784                                 if (parent == NULL) /* break not within loop/switch */
4785                                         return;
4786
4787                                 switch (parent->kind) {
4788                                         case STATEMENT_SWITCH:
4789                                         case STATEMENT_WHILE:
4790                                         case STATEMENT_DO_WHILE:
4791                                         case STATEMENT_FOR:
4792                                                 next = parent->base.next;
4793                                                 goto found_break_parent;
4794
4795                                         default: break;
4796                                 }
4797                         }
4798 found_break_parent:
4799                         break;
4800                 }
4801
4802                 case STATEMENT_GOTO:
4803                         next = stmt->gotos.label->init.statement;
4804                         if (next == NULL) /* missing label */
4805                                 return;
4806                         break;
4807
4808                 case STATEMENT_LABEL:
4809                         next = stmt->label.statement;
4810                         break;
4811
4812                 case STATEMENT_CASE_LABEL:
4813                         next = stmt->case_label.statement;
4814                         break;
4815
4816                 case STATEMENT_WHILE: {
4817                         while_statement_t const *const whiles = &stmt->whiles;
4818                         int                      const val    = determine_truth(whiles->condition);
4819
4820                         if (val >= 0)
4821                                 check_reachable(whiles->body);
4822
4823                         if (val > 0)
4824                                 return;
4825
4826                         next = stmt->base.next;
4827                         break;
4828                 }
4829
4830                 case STATEMENT_DO_WHILE:
4831                         next = stmt->do_while.body;
4832                         break;
4833
4834                 case STATEMENT_FOR: {
4835                         for_statement_t *const fors = &stmt->fors;
4836
4837                         if (fors->condition_reachable)
4838                                 return;
4839                         fors->condition_reachable = true;
4840
4841                         expression_t const *const cond = fors->condition;
4842                         int          const        val  =
4843                                 cond == NULL ? 1 : determine_truth(cond);
4844
4845                         if (val >= 0)
4846                                 check_reachable(fors->body);
4847
4848                         if (val > 0)
4849                                 return;
4850
4851                         next = stmt->base.next;
4852                         break;
4853                 }
4854
4855                 case STATEMENT_MS_TRY:
4856                 case STATEMENT_LEAVE:
4857                         panic("unimplemented");
4858         }
4859
4860         while (next == NULL) {
4861                 next = last->base.parent;
4862                 if (next == NULL) {
4863                         type_t *const type = current_function->type;
4864                         assert(is_type_function(type));
4865                         type_t *const ret  = skip_typeref(type->function.return_type);
4866                         if (warning.return_type                    &&
4867                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
4868                             !is_sym_main(current_function->symbol)) {
4869                                 warningf(&stmt->base.source_position,
4870                                          "control reaches end of non-void function");
4871                         }
4872                         return;
4873                 }
4874
4875                 switch (next->kind) {
4876                         case STATEMENT_INVALID:
4877                         case STATEMENT_EMPTY:
4878                         case STATEMENT_DECLARATION:
4879                         case STATEMENT_EXPRESSION:
4880                         case STATEMENT_ASM:
4881                         case STATEMENT_RETURN:
4882                         case STATEMENT_CONTINUE:
4883                         case STATEMENT_BREAK:
4884                         case STATEMENT_GOTO:
4885                         case STATEMENT_LEAVE:
4886                                 panic("invalid control flow in function");
4887
4888                         case STATEMENT_COMPOUND:
4889                         case STATEMENT_IF:
4890                         case STATEMENT_SWITCH:
4891                         case STATEMENT_LABEL:
4892                         case STATEMENT_CASE_LABEL:
4893                                 last = next;
4894                                 next = next->base.next;
4895                                 break;
4896
4897                         case STATEMENT_WHILE: {
4898 continue_while:
4899                                 if (next->base.reachable)
4900                                         return;
4901                                 next->base.reachable = true;
4902
4903                                 while_statement_t const *const whiles = &next->whiles;
4904                                 int                      const val    = determine_truth(whiles->condition);
4905
4906                                 if (val >= 0)
4907                                         check_reachable(whiles->body);
4908
4909                                 if (val > 0)
4910                                         return;
4911
4912                                 last = next;
4913                                 next = next->base.next;
4914                                 break;
4915                         }
4916
4917                         case STATEMENT_DO_WHILE: {
4918 continue_do_while:
4919                                 if (next->base.reachable)
4920                                         return;
4921                                 next->base.reachable = true;
4922
4923                                 do_while_statement_t const *const dw  = &next->do_while;
4924                                 int                  const        val = determine_truth(dw->condition);
4925
4926                                 if (val >= 0)
4927                                         check_reachable(dw->body);
4928
4929                                 if (val > 0)
4930                                         return;
4931
4932                                 last = next;
4933                                 next = next->base.next;
4934                                 break;
4935                         }
4936
4937                         case STATEMENT_FOR: {
4938 continue_for:;
4939                                 for_statement_t *const fors = &next->fors;
4940
4941                                 fors->step_reachable = true;
4942
4943                                 if (fors->condition_reachable)
4944                                         return;
4945                                 fors->condition_reachable = true;
4946
4947                                 expression_t const *const cond = fors->condition;
4948                                 int          const        val  =
4949                                         cond == NULL ? 1 : determine_truth(cond);
4950
4951                                 if (val >= 0)
4952                                         check_reachable(fors->body);
4953
4954                                 if (val > 0)
4955                                         return;
4956
4957                                 last = next;
4958                                 next = next->base.next;
4959                                 break;
4960                         }
4961
4962                         case STATEMENT_MS_TRY:
4963                                 panic("unimplemented");
4964                 }
4965         }
4966
4967         if (next == NULL) {
4968                 next = stmt->base.parent;
4969                 if (next == NULL) {
4970                         warningf(&stmt->base.source_position,
4971                                  "control reaches end of non-void function");
4972                 }
4973         }
4974
4975         check_reachable(next);
4976 }
4977
4978 static void check_unreachable(statement_t const* const stmt)
4979 {
4980         if (!stmt->base.reachable            &&
4981             stmt->kind != STATEMENT_COMPOUND &&
4982             stmt->kind != STATEMENT_DO_WHILE &&
4983             stmt->kind != STATEMENT_FOR) {
4984                 warningf(&stmt->base.source_position,
4985                          "statement is unreachable");
4986         }
4987
4988         switch (stmt->kind) {
4989                 case STATEMENT_INVALID:
4990                 case STATEMENT_EMPTY:
4991                 case STATEMENT_RETURN:
4992                 case STATEMENT_DECLARATION:
4993                 case STATEMENT_EXPRESSION:
4994                 case STATEMENT_CONTINUE:
4995                 case STATEMENT_BREAK:
4996                 case STATEMENT_GOTO:
4997                 case STATEMENT_ASM:
4998                 case STATEMENT_LEAVE:
4999                         break;
5000
5001                 case STATEMENT_COMPOUND:
5002                         if (stmt->compound.statements)
5003                                 check_unreachable(stmt->compound.statements);
5004                         break;
5005
5006                 case STATEMENT_IF:
5007                         check_unreachable(stmt->ifs.true_statement);
5008                         if (stmt->ifs.false_statement != NULL)
5009                                 check_unreachable(stmt->ifs.false_statement);
5010                         break;
5011
5012                 case STATEMENT_SWITCH:
5013                         check_unreachable(stmt->switchs.body);
5014                         break;
5015
5016                 case STATEMENT_LABEL:
5017                         check_unreachable(stmt->label.statement);
5018                         break;
5019
5020                 case STATEMENT_CASE_LABEL:
5021                         check_unreachable(stmt->case_label.statement);
5022                         break;
5023
5024                 case STATEMENT_WHILE:
5025                         check_unreachable(stmt->whiles.body);
5026                         break;
5027
5028                 case STATEMENT_DO_WHILE:
5029                         check_unreachable(stmt->do_while.body);
5030                         if (!stmt->base.reachable) {
5031                                 expression_t const *const cond = stmt->do_while.condition;
5032                                 if (determine_truth(cond) >= 0) {
5033                                         warningf(&cond->base.source_position,
5034                                                  "condition of do-while-loop is unreachable");
5035                                 }
5036                         }
5037                         break;
5038
5039                 case STATEMENT_FOR: {
5040                         for_statement_t const* const fors = &stmt->fors;
5041
5042                         if (!stmt->base.reachable && fors->initialisation != NULL) {
5043                                 warningf(&fors->initialisation->base.source_position,
5044                                          "initialisation of for-statement is unreachable");
5045                         }
5046
5047                         if (!fors->condition_reachable && fors->condition != NULL) {
5048                                 warningf(&fors->condition->base.source_position,
5049                                          "condition of for-statement is unreachable");
5050                         }
5051
5052                         if (!fors->step_reachable && fors->step != NULL) {
5053                                 warningf(&fors->step->base.source_position,
5054                                          "step of for-statement is unreachable");
5055                         }
5056
5057                         check_unreachable(stmt->fors.body);
5058                         break;
5059                 }
5060
5061                 case STATEMENT_MS_TRY:
5062                         panic("unimplemented");
5063         }
5064
5065         if (stmt->base.next)
5066                 check_unreachable(stmt->base.next);
5067 }
5068
5069 static void parse_external_declaration(void)
5070 {
5071         /* function-definitions and declarations both start with declaration
5072          * specifiers */
5073         declaration_specifiers_t specifiers;
5074         memset(&specifiers, 0, sizeof(specifiers));
5075
5076         add_anchor_token(';');
5077         parse_declaration_specifiers(&specifiers);
5078         rem_anchor_token(';');
5079
5080         /* must be a declaration */
5081         if (token.type == ';') {
5082                 parse_anonymous_declaration_rest(&specifiers, append_declaration);
5083                 return;
5084         }
5085
5086         add_anchor_token(',');
5087         add_anchor_token('=');
5088         rem_anchor_token(';');
5089
5090         /* declarator is common to both function-definitions and declarations */
5091         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5092
5093         rem_anchor_token(',');
5094         rem_anchor_token('=');
5095         rem_anchor_token(';');
5096
5097         /* must be a declaration */
5098         switch (token.type) {
5099                 case ',':
5100                 case ';':
5101                         parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
5102                         return;
5103
5104                 case '=':
5105                         parse_declaration_rest(ndeclaration, &specifiers, record_definition);
5106                         return;
5107         }
5108
5109         /* must be a function definition */
5110         parse_kr_declaration_list(ndeclaration);
5111
5112         if (token.type != '{') {
5113                 parse_error_expected("while parsing function definition", '{', NULL);
5114                 eat_until_matching_token(';');
5115                 return;
5116         }
5117
5118         type_t *type = ndeclaration->type;
5119
5120         /* note that we don't skip typerefs: the standard doesn't allow them here
5121          * (so we can't use is_type_function here) */
5122         if (type->kind != TYPE_FUNCTION) {
5123                 if (is_type_valid(type)) {
5124                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5125                                type, ndeclaration->symbol);
5126                 }
5127                 eat_block();
5128                 return;
5129         }
5130
5131         /* § 6.7.5.3 (14) a function definition with () means no
5132          * parameters (and not unspecified parameters) */
5133         if (type->function.unspecified_parameters
5134                         && type->function.parameters == NULL
5135                         && !type->function.kr_style_parameters) {
5136                 type_t *duplicate = duplicate_type(type);
5137                 duplicate->function.unspecified_parameters = false;
5138
5139                 type = typehash_insert(duplicate);
5140                 if (type != duplicate) {
5141                         obstack_free(type_obst, duplicate);
5142                 }
5143                 ndeclaration->type = type;
5144         }
5145
5146         declaration_t *const declaration = record_definition(ndeclaration);
5147         if (ndeclaration != declaration) {
5148                 declaration->scope = ndeclaration->scope;
5149         }
5150         type = skip_typeref(declaration->type);
5151
5152         /* push function parameters and switch scope */
5153         int       top        = environment_top();
5154         scope_t  *last_scope = scope;
5155         set_scope(&declaration->scope);
5156
5157         declaration_t *parameter = declaration->scope.declarations;
5158         for( ; parameter != NULL; parameter = parameter->next) {
5159                 if (parameter->parent_scope == &ndeclaration->scope) {
5160                         parameter->parent_scope = scope;
5161                 }
5162                 assert(parameter->parent_scope == NULL
5163                                 || parameter->parent_scope == scope);
5164                 parameter->parent_scope = scope;
5165                 if (parameter->symbol == NULL) {
5166                         errorf(&ndeclaration->source_position, "parameter name omitted");
5167                         continue;
5168                 }
5169                 environment_push(parameter);
5170         }
5171
5172         if (declaration->init.statement != NULL) {
5173                 parser_error_multiple_definition(declaration, HERE);
5174                 eat_block();
5175         } else {
5176                 /* parse function body */
5177                 int            label_stack_top      = label_top();
5178                 declaration_t *old_current_function = current_function;
5179                 current_function                    = declaration;
5180                 current_parent                      = NULL;
5181
5182                 statement_t *const body = parse_compound_statement(false);
5183                 declaration->init.statement = body;
5184                 first_err = true;
5185                 check_labels();
5186                 check_declarations();
5187                 if (warning.return_type || warning.unreachable_code) {
5188                         check_reachable(body);
5189                         if (warning.unreachable_code)
5190                                 check_unreachable(body);
5191                 }
5192
5193                 assert(current_parent   == NULL);
5194                 assert(current_function == declaration);
5195                 current_function = old_current_function;
5196                 label_pop_to(label_stack_top);
5197         }
5198
5199         assert(scope == &declaration->scope);
5200         set_scope(last_scope);
5201         environment_pop_to(top);
5202 }
5203
5204 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5205                                   source_position_t *source_position)
5206 {
5207         type_t *type = allocate_type_zero(TYPE_BITFIELD, source_position);
5208
5209         type->bitfield.base_type = base_type;
5210         type->bitfield.size      = size;
5211
5212         return type;
5213 }
5214
5215 static declaration_t *find_compound_entry(declaration_t *compound_declaration,
5216                                           symbol_t *symbol)
5217 {
5218         declaration_t *iter = compound_declaration->scope.declarations;
5219         for( ; iter != NULL; iter = iter->next) {
5220                 if (iter->namespc != NAMESPACE_NORMAL)
5221                         continue;
5222
5223                 if (iter->symbol == NULL) {
5224                         type_t *type = skip_typeref(iter->type);
5225                         if (is_type_compound(type)) {
5226                                 declaration_t *result
5227                                         = find_compound_entry(type->compound.declaration, symbol);
5228                                 if (result != NULL)
5229                                         return result;
5230                         }
5231                         continue;
5232                 }
5233
5234                 if (iter->symbol == symbol) {
5235                         return iter;
5236                 }
5237         }
5238
5239         return NULL;
5240 }
5241
5242 static void parse_compound_declarators(declaration_t *struct_declaration,
5243                 const declaration_specifiers_t *specifiers)
5244 {
5245         declaration_t *last_declaration = struct_declaration->scope.declarations;
5246         if (last_declaration != NULL) {
5247                 while(last_declaration->next != NULL) {
5248                         last_declaration = last_declaration->next;
5249                 }
5250         }
5251
5252         while(1) {
5253                 declaration_t *declaration;
5254
5255                 if (token.type == ':') {
5256                         source_position_t source_position = *HERE;
5257                         next_token();
5258
5259                         type_t *base_type = specifiers->type;
5260                         expression_t *size = parse_constant_expression();
5261
5262                         if (!is_type_integer(skip_typeref(base_type))) {
5263                                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5264                                        base_type);
5265                         }
5266
5267                         type_t *type = make_bitfield_type(base_type, size, &source_position);
5268
5269                         declaration                         = allocate_declaration_zero();
5270                         declaration->namespc                = NAMESPACE_NORMAL;
5271                         declaration->declared_storage_class = STORAGE_CLASS_NONE;
5272                         declaration->storage_class          = STORAGE_CLASS_NONE;
5273                         declaration->source_position        = source_position;
5274                         declaration->modifiers              = specifiers->modifiers;
5275                         declaration->type                   = type;
5276                 } else {
5277                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
5278
5279                         type_t *orig_type = declaration->type;
5280                         type_t *type      = skip_typeref(orig_type);
5281
5282                         if (token.type == ':') {
5283                                 source_position_t source_position = *HERE;
5284                                 next_token();
5285                                 expression_t *size = parse_constant_expression();
5286
5287                                 if (!is_type_integer(type)) {
5288                                         errorf(HERE, "bitfield base type '%T' is not an "
5289                                                "integer type", orig_type);
5290                                 }
5291
5292                                 type_t *bitfield_type = make_bitfield_type(orig_type, size, &source_position);
5293                                 declaration->type = bitfield_type;
5294                         } else {
5295                                 /* TODO we ignore arrays for now... what is missing is a check
5296                                  * that they're at the end of the struct */
5297                                 if (is_type_incomplete(type) && !is_type_array(type)) {
5298                                         errorf(HERE,
5299                                                "compound member '%Y' has incomplete type '%T'",
5300                                                declaration->symbol, orig_type);
5301                                 } else if (is_type_function(type)) {
5302                                         errorf(HERE, "compound member '%Y' must not have function "
5303                                                "type '%T'", declaration->symbol, orig_type);
5304                                 }
5305                         }
5306                 }
5307
5308                 /* make sure we don't define a symbol multiple times */
5309                 symbol_t *symbol = declaration->symbol;
5310                 if (symbol != NULL) {
5311                         declaration_t *prev_decl
5312                                 = find_compound_entry(struct_declaration, symbol);
5313
5314                         if (prev_decl != NULL) {
5315                                 assert(prev_decl->symbol == symbol);
5316                                 errorf(&declaration->source_position,
5317                                        "multiple declarations of symbol '%Y' (declared %P)",
5318                                        symbol, &prev_decl->source_position);
5319                         }
5320                 }
5321
5322                 /* append declaration */
5323                 if (last_declaration != NULL) {
5324                         last_declaration->next = declaration;
5325                 } else {
5326                         struct_declaration->scope.declarations = declaration;
5327                 }
5328                 last_declaration = declaration;
5329
5330                 if (token.type != ',')
5331                         break;
5332                 next_token();
5333         }
5334         expect(';');
5335
5336 end_error:
5337         ;
5338 }
5339
5340 static void parse_compound_type_entries(declaration_t *compound_declaration)
5341 {
5342         eat('{');
5343         add_anchor_token('}');
5344
5345         while(token.type != '}' && token.type != T_EOF) {
5346                 declaration_specifiers_t specifiers;
5347                 memset(&specifiers, 0, sizeof(specifiers));
5348                 parse_declaration_specifiers(&specifiers);
5349
5350                 parse_compound_declarators(compound_declaration, &specifiers);
5351         }
5352         rem_anchor_token('}');
5353
5354         if (token.type == T_EOF) {
5355                 errorf(HERE, "EOF while parsing struct");
5356         }
5357         next_token();
5358 }
5359
5360 static type_t *parse_typename(void)
5361 {
5362         declaration_specifiers_t specifiers;
5363         memset(&specifiers, 0, sizeof(specifiers));
5364         parse_declaration_specifiers(&specifiers);
5365         if (specifiers.declared_storage_class != STORAGE_CLASS_NONE) {
5366                 /* TODO: improve error message, user does probably not know what a
5367                  * storage class is...
5368                  */
5369                 errorf(HERE, "typename may not have a storage class");
5370         }
5371
5372         type_t *result = parse_abstract_declarator(specifiers.type);
5373
5374         return result;
5375 }
5376
5377
5378
5379
5380 typedef expression_t* (*parse_expression_function) (unsigned precedence);
5381 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
5382                                                           expression_t *left);
5383
5384 typedef struct expression_parser_function_t expression_parser_function_t;
5385 struct expression_parser_function_t {
5386         unsigned                         precedence;
5387         parse_expression_function        parser;
5388         unsigned                         infix_precedence;
5389         parse_expression_infix_function  infix_parser;
5390 };
5391
5392 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5393
5394 /**
5395  * Prints an error message if an expression was expected but not read
5396  */
5397 static expression_t *expected_expression_error(void)
5398 {
5399         /* skip the error message if the error token was read */
5400         if (token.type != T_ERROR) {
5401                 errorf(HERE, "expected expression, got token '%K'", &token);
5402         }
5403         next_token();
5404
5405         return create_invalid_expression();
5406 }
5407
5408 /**
5409  * Parse a string constant.
5410  */
5411 static expression_t *parse_string_const(void)
5412 {
5413         wide_string_t wres;
5414         if (token.type == T_STRING_LITERAL) {
5415                 string_t res = token.v.string;
5416                 next_token();
5417                 while (token.type == T_STRING_LITERAL) {
5418                         res = concat_strings(&res, &token.v.string);
5419                         next_token();
5420                 }
5421                 if (token.type != T_WIDE_STRING_LITERAL) {
5422                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
5423                         /* note: that we use type_char_ptr here, which is already the
5424                          * automatic converted type. revert_automatic_type_conversion
5425                          * will construct the array type */
5426                         cnst->base.type    = type_char_ptr;
5427                         cnst->string.value = res;
5428                         return cnst;
5429                 }
5430
5431                 wres = concat_string_wide_string(&res, &token.v.wide_string);
5432         } else {
5433                 wres = token.v.wide_string;
5434         }
5435         next_token();
5436
5437         for (;;) {
5438                 switch (token.type) {
5439                         case T_WIDE_STRING_LITERAL:
5440                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
5441                                 break;
5442
5443                         case T_STRING_LITERAL:
5444                                 wres = concat_wide_string_string(&wres, &token.v.string);
5445                                 break;
5446
5447                         default: {
5448                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
5449                                 cnst->base.type         = type_wchar_t_ptr;
5450                                 cnst->wide_string.value = wres;
5451                                 return cnst;
5452                         }
5453                 }
5454                 next_token();
5455         }
5456 }
5457
5458 /**
5459  * Parse an integer constant.
5460  */
5461 static expression_t *parse_int_const(void)
5462 {
5463         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5464         cnst->base.source_position = *HERE;
5465         cnst->base.type            = token.datatype;
5466         cnst->conste.v.int_value   = token.v.intvalue;
5467
5468         next_token();
5469
5470         return cnst;
5471 }
5472
5473 /**
5474  * Parse a character constant.
5475  */
5476 static expression_t *parse_character_constant(void)
5477 {
5478         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
5479
5480         cnst->base.source_position = *HERE;
5481         cnst->base.type            = token.datatype;
5482         cnst->conste.v.character   = token.v.string;
5483
5484         if (cnst->conste.v.character.size != 1) {
5485                 if (warning.multichar && (c_mode & _GNUC)) {
5486                         /* TODO */
5487                         warningf(HERE, "multi-character character constant");
5488                 } else {
5489                         errorf(HERE, "more than 1 characters in character constant");
5490                 }
5491         }
5492         next_token();
5493
5494         return cnst;
5495 }
5496
5497 /**
5498  * Parse a wide character constant.
5499  */
5500 static expression_t *parse_wide_character_constant(void)
5501 {
5502         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
5503
5504         cnst->base.source_position    = *HERE;
5505         cnst->base.type               = token.datatype;
5506         cnst->conste.v.wide_character = token.v.wide_string;
5507
5508         if (cnst->conste.v.wide_character.size != 1) {
5509                 if (warning.multichar && (c_mode & _GNUC)) {
5510                         /* TODO */
5511                         warningf(HERE, "multi-character character constant");
5512                 } else {
5513                         errorf(HERE, "more than 1 characters in character constant");
5514                 }
5515         }
5516         next_token();
5517
5518         return cnst;
5519 }
5520
5521 /**
5522  * Parse a float constant.
5523  */
5524 static expression_t *parse_float_const(void)
5525 {
5526         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5527         cnst->base.type            = token.datatype;
5528         cnst->conste.v.float_value = token.v.floatvalue;
5529
5530         next_token();
5531
5532         return cnst;
5533 }
5534
5535 static declaration_t *create_implicit_function(symbol_t *symbol,
5536                 const source_position_t *source_position)
5537 {
5538         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION, source_position);
5539         ntype->function.return_type            = type_int;
5540         ntype->function.unspecified_parameters = true;
5541
5542         type_t *type = typehash_insert(ntype);
5543         if (type != ntype) {
5544                 free_type(ntype);
5545         }
5546
5547         declaration_t *const declaration    = allocate_declaration_zero();
5548         declaration->storage_class          = STORAGE_CLASS_EXTERN;
5549         declaration->declared_storage_class = STORAGE_CLASS_EXTERN;
5550         declaration->type                   = type;
5551         declaration->symbol                 = symbol;
5552         declaration->source_position        = *source_position;
5553
5554         bool strict_prototypes_old = warning.strict_prototypes;
5555         warning.strict_prototypes  = false;
5556         record_declaration(declaration);
5557         warning.strict_prototypes = strict_prototypes_old;
5558
5559         return declaration;
5560 }
5561
5562 /**
5563  * Creates a return_type (func)(argument_type) function type if not
5564  * already exists.
5565  */
5566 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
5567                                     type_t *argument_type2)
5568 {
5569         function_parameter_t *parameter2
5570                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
5571         memset(parameter2, 0, sizeof(parameter2[0]));
5572         parameter2->type = argument_type2;
5573
5574         function_parameter_t *parameter1
5575                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
5576         memset(parameter1, 0, sizeof(parameter1[0]));
5577         parameter1->type = argument_type1;
5578         parameter1->next = parameter2;
5579
5580         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5581         type->function.return_type = return_type;
5582         type->function.parameters  = parameter1;
5583
5584         type_t *result = typehash_insert(type);
5585         if (result != type) {
5586                 free_type(type);
5587         }
5588
5589         return result;
5590 }
5591
5592 /**
5593  * Creates a return_type (func)(argument_type) function type if not
5594  * already exists.
5595  *
5596  * @param return_type    the return type
5597  * @param argument_type  the argument type
5598  */
5599 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
5600 {
5601         function_parameter_t *parameter
5602                 = obstack_alloc(type_obst, sizeof(parameter[0]));
5603         memset(parameter, 0, sizeof(parameter[0]));
5604         parameter->type = argument_type;
5605
5606         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5607         type->function.return_type = return_type;
5608         type->function.parameters  = parameter;
5609
5610         type_t *result = typehash_insert(type);
5611         if (result != type) {
5612                 free_type(type);
5613         }
5614
5615         return result;
5616 }
5617
5618 static type_t *make_function_0_type(type_t *return_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  = NULL;
5623
5624         type_t *result = typehash_insert(type);
5625         if (result != type) {
5626                 free_type(type);
5627         }
5628
5629         return result;
5630 }
5631
5632 /**
5633  * Creates a function type for some function like builtins.
5634  *
5635  * @param symbol   the symbol describing the builtin
5636  */
5637 static type_t *get_builtin_symbol_type(symbol_t *symbol)
5638 {
5639         switch(symbol->ID) {
5640         case T___builtin_alloca:
5641                 return make_function_1_type(type_void_ptr, type_size_t);
5642         case T___builtin_huge_val:
5643                 return make_function_0_type(type_double);
5644         case T___builtin_nan:
5645                 return make_function_1_type(type_double, type_char_ptr);
5646         case T___builtin_nanf:
5647                 return make_function_1_type(type_float, type_char_ptr);
5648         case T___builtin_nand:
5649                 return make_function_1_type(type_long_double, type_char_ptr);
5650         case T___builtin_va_end:
5651                 return make_function_1_type(type_void, type_valist);
5652         case T___builtin_expect:
5653                 return make_function_2_type(type_long, type_long, type_long);
5654         default:
5655                 internal_errorf(HERE, "not implemented builtin symbol found");
5656         }
5657 }
5658
5659 /**
5660  * Performs automatic type cast as described in § 6.3.2.1.
5661  *
5662  * @param orig_type  the original type
5663  */
5664 static type_t *automatic_type_conversion(type_t *orig_type)
5665 {
5666         type_t *type = skip_typeref(orig_type);
5667         if (is_type_array(type)) {
5668                 array_type_t *array_type   = &type->array;
5669                 type_t       *element_type = array_type->element_type;
5670                 unsigned      qualifiers   = array_type->base.qualifiers;
5671
5672                 return make_pointer_type(element_type, qualifiers);
5673         }
5674
5675         if (is_type_function(type)) {
5676                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
5677         }
5678
5679         return orig_type;
5680 }
5681
5682 /**
5683  * reverts the automatic casts of array to pointer types and function
5684  * to function-pointer types as defined § 6.3.2.1
5685  */
5686 type_t *revert_automatic_type_conversion(const expression_t *expression)
5687 {
5688         switch (expression->kind) {
5689                 case EXPR_REFERENCE: return expression->reference.declaration->type;
5690                 case EXPR_SELECT:    return expression->select.compound_entry->type;
5691
5692                 case EXPR_UNARY_DEREFERENCE: {
5693                         const expression_t *const value = expression->unary.value;
5694                         type_t             *const type  = skip_typeref(value->base.type);
5695                         assert(is_type_pointer(type));
5696                         return type->pointer.points_to;
5697                 }
5698
5699                 case EXPR_BUILTIN_SYMBOL:
5700                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
5701
5702                 case EXPR_ARRAY_ACCESS: {
5703                         const expression_t *array_ref = expression->array_access.array_ref;
5704                         type_t             *type_left = skip_typeref(array_ref->base.type);
5705                         if (!is_type_valid(type_left))
5706                                 return type_left;
5707                         assert(is_type_pointer(type_left));
5708                         return type_left->pointer.points_to;
5709                 }
5710
5711                 case EXPR_STRING_LITERAL: {
5712                         size_t size = expression->string.value.size;
5713                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
5714                 }
5715
5716                 case EXPR_WIDE_STRING_LITERAL: {
5717                         size_t size = expression->wide_string.value.size;
5718                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
5719                 }
5720
5721                 case EXPR_COMPOUND_LITERAL:
5722                         return expression->compound_literal.type;
5723
5724                 default: break;
5725         }
5726
5727         return expression->base.type;
5728 }
5729
5730 static expression_t *parse_reference(void)
5731 {
5732         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
5733
5734         reference_expression_t *ref = &expression->reference;
5735         symbol_t *const symbol = token.v.symbol;
5736
5737         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
5738
5739         source_position_t source_position = token.source_position;
5740         next_token();
5741
5742         if (declaration == NULL) {
5743                 if (! strict_mode && token.type == '(') {
5744                         /* an implicitly defined function */
5745                         if (warning.implicit_function_declaration) {
5746                                 warningf(HERE, "implicit declaration of function '%Y'",
5747                                         symbol);
5748                         }
5749
5750                         declaration = create_implicit_function(symbol,
5751                                                                &source_position);
5752                 } else {
5753                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
5754                         return create_invalid_expression();
5755                 }
5756         }
5757
5758         type_t *type         = declaration->type;
5759
5760         /* we always do the auto-type conversions; the & and sizeof parser contains
5761          * code to revert this! */
5762         type = automatic_type_conversion(type);
5763
5764         ref->declaration = declaration;
5765         ref->base.type   = type;
5766
5767         /* this declaration is used */
5768         declaration->used = true;
5769
5770         /* check for deprecated functions */
5771         if (warning.deprecated_declarations &&
5772             declaration->modifiers & DM_DEPRECATED) {
5773                 char const *const prefix = is_type_function(declaration->type) ?
5774                         "function" : "variable";
5775
5776                 if (declaration->deprecated_string != NULL) {
5777                         warningf(&source_position,
5778                                 "%s '%Y' is deprecated (declared %P): \"%s\"", prefix,
5779                                 declaration->symbol, &declaration->source_position,
5780                                 declaration->deprecated_string);
5781                 } else {
5782                         warningf(&source_position,
5783                                 "%s '%Y' is deprecated (declared %P)", prefix,
5784                                 declaration->symbol, &declaration->source_position);
5785                 }
5786         }
5787
5788         return expression;
5789 }
5790
5791 static void check_cast_allowed(expression_t *expression, type_t *dest_type)
5792 {
5793         (void) expression;
5794         (void) dest_type;
5795         /* TODO check if explicit cast is allowed and issue warnings/errors */
5796 }
5797
5798 static expression_t *parse_compound_literal(type_t *type)
5799 {
5800         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
5801
5802         parse_initializer_env_t env;
5803         env.type             = type;
5804         env.declaration      = NULL;
5805         env.must_be_constant = false;
5806         initializer_t *initializer = parse_initializer(&env);
5807         type = env.type;
5808
5809         expression->compound_literal.initializer = initializer;
5810         expression->compound_literal.type        = type;
5811         expression->base.type                    = automatic_type_conversion(type);
5812
5813         return expression;
5814 }
5815
5816 /**
5817  * Parse a cast expression.
5818  */
5819 static expression_t *parse_cast(void)
5820 {
5821         source_position_t source_position = token.source_position;
5822
5823         type_t *type  = parse_typename();
5824
5825         /* matching add_anchor_token() is at call site */
5826         rem_anchor_token(')');
5827         expect(')');
5828
5829         if (token.type == '{') {
5830                 return parse_compound_literal(type);
5831         }
5832
5833         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
5834         cast->base.source_position = source_position;
5835
5836         expression_t *value = parse_sub_expression(20);
5837
5838         check_cast_allowed(value, type);
5839
5840         cast->base.type   = type;
5841         cast->unary.value = value;
5842
5843         return cast;
5844 end_error:
5845         return create_invalid_expression();
5846 }
5847
5848 /**
5849  * Parse a statement expression.
5850  */
5851 static expression_t *parse_statement_expression(void)
5852 {
5853         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
5854
5855         statement_t *statement           = parse_compound_statement(true);
5856         expression->statement.statement  = statement;
5857         expression->base.source_position = statement->base.source_position;
5858
5859         /* find last statement and use its type */
5860         type_t *type = type_void;
5861         const statement_t *stmt = statement->compound.statements;
5862         if (stmt != NULL) {
5863                 while (stmt->base.next != NULL)
5864                         stmt = stmt->base.next;
5865
5866                 if (stmt->kind == STATEMENT_EXPRESSION) {
5867                         type = stmt->expression.expression->base.type;
5868                 }
5869         } else {
5870                 warningf(&expression->base.source_position, "empty statement expression ({})");
5871         }
5872         expression->base.type = type;
5873
5874         expect(')');
5875
5876         return expression;
5877 end_error:
5878         return create_invalid_expression();
5879 }
5880
5881 /**
5882  * Parse a braced expression.
5883  */
5884 static expression_t *parse_brace_expression(void)
5885 {
5886         eat('(');
5887         add_anchor_token(')');
5888
5889         switch(token.type) {
5890         case '{':
5891                 /* gcc extension: a statement expression */
5892                 return parse_statement_expression();
5893
5894         TYPE_QUALIFIERS
5895         TYPE_SPECIFIERS
5896                 return parse_cast();
5897         case T_IDENTIFIER:
5898                 if (is_typedef_symbol(token.v.symbol)) {
5899                         return parse_cast();
5900                 }
5901         }
5902
5903         expression_t *result = parse_expression();
5904         rem_anchor_token(')');
5905         expect(')');
5906
5907         return result;
5908 end_error:
5909         return create_invalid_expression();
5910 }
5911
5912 static expression_t *parse_function_keyword(void)
5913 {
5914         next_token();
5915         /* TODO */
5916
5917         if (current_function == NULL) {
5918                 errorf(HERE, "'__func__' used outside of a function");
5919         }
5920
5921         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5922         expression->base.type     = type_char_ptr;
5923         expression->funcname.kind = FUNCNAME_FUNCTION;
5924
5925         return expression;
5926 }
5927
5928 static expression_t *parse_pretty_function_keyword(void)
5929 {
5930         eat(T___PRETTY_FUNCTION__);
5931
5932         if (current_function == NULL) {
5933                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
5934         }
5935
5936         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5937         expression->base.type     = type_char_ptr;
5938         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
5939
5940         return expression;
5941 }
5942
5943 static expression_t *parse_funcsig_keyword(void)
5944 {
5945         eat(T___FUNCSIG__);
5946
5947         if (current_function == NULL) {
5948                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
5949         }
5950
5951         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5952         expression->base.type     = type_char_ptr;
5953         expression->funcname.kind = FUNCNAME_FUNCSIG;
5954
5955         return expression;
5956 }
5957
5958 static expression_t *parse_funcdname_keyword(void)
5959 {
5960         eat(T___FUNCDNAME__);
5961
5962         if (current_function == NULL) {
5963                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
5964         }
5965
5966         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5967         expression->base.type     = type_char_ptr;
5968         expression->funcname.kind = FUNCNAME_FUNCDNAME;
5969
5970         return expression;
5971 }
5972
5973 static designator_t *parse_designator(void)
5974 {
5975         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
5976         result->source_position = *HERE;
5977
5978         if (token.type != T_IDENTIFIER) {
5979                 parse_error_expected("while parsing member designator",
5980                                      T_IDENTIFIER, NULL);
5981                 return NULL;
5982         }
5983         result->symbol = token.v.symbol;
5984         next_token();
5985
5986         designator_t *last_designator = result;
5987         while(true) {
5988                 if (token.type == '.') {
5989                         next_token();
5990                         if (token.type != T_IDENTIFIER) {
5991                                 parse_error_expected("while parsing member designator",
5992                                                      T_IDENTIFIER, NULL);
5993                                 return NULL;
5994                         }
5995                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
5996                         designator->source_position = *HERE;
5997                         designator->symbol          = token.v.symbol;
5998                         next_token();
5999
6000                         last_designator->next = designator;
6001                         last_designator       = designator;
6002                         continue;
6003                 }
6004                 if (token.type == '[') {
6005                         next_token();
6006                         add_anchor_token(']');
6007                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6008                         designator->source_position = *HERE;
6009                         designator->array_index     = parse_expression();
6010                         rem_anchor_token(']');
6011                         expect(']');
6012                         if (designator->array_index == NULL) {
6013                                 return NULL;
6014                         }
6015
6016                         last_designator->next = designator;
6017                         last_designator       = designator;
6018                         continue;
6019                 }
6020                 break;
6021         }
6022
6023         return result;
6024 end_error:
6025         return NULL;
6026 }
6027
6028 /**
6029  * Parse the __builtin_offsetof() expression.
6030  */
6031 static expression_t *parse_offsetof(void)
6032 {
6033         eat(T___builtin_offsetof);
6034
6035         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6036         expression->base.type    = type_size_t;
6037
6038         expect('(');
6039         add_anchor_token(',');
6040         type_t *type = parse_typename();
6041         rem_anchor_token(',');
6042         expect(',');
6043         add_anchor_token(')');
6044         designator_t *designator = parse_designator();
6045         rem_anchor_token(')');
6046         expect(')');
6047
6048         expression->offsetofe.type       = type;
6049         expression->offsetofe.designator = designator;
6050
6051         type_path_t path;
6052         memset(&path, 0, sizeof(path));
6053         path.top_type = type;
6054         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6055
6056         descend_into_subtype(&path);
6057
6058         if (!walk_designator(&path, designator, true)) {
6059                 return create_invalid_expression();
6060         }
6061
6062         DEL_ARR_F(path.path);
6063
6064         return expression;
6065 end_error:
6066         return create_invalid_expression();
6067 }
6068
6069 /**
6070  * Parses a _builtin_va_start() expression.
6071  */
6072 static expression_t *parse_va_start(void)
6073 {
6074         eat(T___builtin_va_start);
6075
6076         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6077
6078         expect('(');
6079         add_anchor_token(',');
6080         expression->va_starte.ap = parse_assignment_expression();
6081         rem_anchor_token(',');
6082         expect(',');
6083         expression_t *const expr = parse_assignment_expression();
6084         if (expr->kind == EXPR_REFERENCE) {
6085                 declaration_t *const decl = expr->reference.declaration;
6086                 if (decl == NULL)
6087                         return create_invalid_expression();
6088                 if (decl->parent_scope == &current_function->scope &&
6089                     decl->next == NULL) {
6090                         expression->va_starte.parameter = decl;
6091                         expect(')');
6092                         return expression;
6093                 }
6094         }
6095         errorf(&expr->base.source_position,
6096                "second argument of 'va_start' must be last parameter of the current function");
6097 end_error:
6098         return create_invalid_expression();
6099 }
6100
6101 /**
6102  * Parses a _builtin_va_arg() expression.
6103  */
6104 static expression_t *parse_va_arg(void)
6105 {
6106         eat(T___builtin_va_arg);
6107
6108         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6109
6110         expect('(');
6111         expression->va_arge.ap = parse_assignment_expression();
6112         expect(',');
6113         expression->base.type = parse_typename();
6114         expect(')');
6115
6116         return expression;
6117 end_error:
6118         return create_invalid_expression();
6119 }
6120
6121 static expression_t *parse_builtin_symbol(void)
6122 {
6123         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
6124
6125         symbol_t *symbol = token.v.symbol;
6126
6127         expression->builtin_symbol.symbol = symbol;
6128         next_token();
6129
6130         type_t *type = get_builtin_symbol_type(symbol);
6131         type = automatic_type_conversion(type);
6132
6133         expression->base.type = type;
6134         return expression;
6135 }
6136
6137 /**
6138  * Parses a __builtin_constant() expression.
6139  */
6140 static expression_t *parse_builtin_constant(void)
6141 {
6142         eat(T___builtin_constant_p);
6143
6144         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6145
6146         expect('(');
6147         add_anchor_token(')');
6148         expression->builtin_constant.value = parse_assignment_expression();
6149         rem_anchor_token(')');
6150         expect(')');
6151         expression->base.type = type_int;
6152
6153         return expression;
6154 end_error:
6155         return create_invalid_expression();
6156 }
6157
6158 /**
6159  * Parses a __builtin_prefetch() expression.
6160  */
6161 static expression_t *parse_builtin_prefetch(void)
6162 {
6163         eat(T___builtin_prefetch);
6164
6165         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
6166
6167         expect('(');
6168         add_anchor_token(')');
6169         expression->builtin_prefetch.adr = parse_assignment_expression();
6170         if (token.type == ',') {
6171                 next_token();
6172                 expression->builtin_prefetch.rw = parse_assignment_expression();
6173         }
6174         if (token.type == ',') {
6175                 next_token();
6176                 expression->builtin_prefetch.locality = parse_assignment_expression();
6177         }
6178         rem_anchor_token(')');
6179         expect(')');
6180         expression->base.type = type_void;
6181
6182         return expression;
6183 end_error:
6184         return create_invalid_expression();
6185 }
6186
6187 /**
6188  * Parses a __builtin_is_*() compare expression.
6189  */
6190 static expression_t *parse_compare_builtin(void)
6191 {
6192         expression_t *expression;
6193
6194         switch(token.type) {
6195         case T___builtin_isgreater:
6196                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6197                 break;
6198         case T___builtin_isgreaterequal:
6199                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6200                 break;
6201         case T___builtin_isless:
6202                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6203                 break;
6204         case T___builtin_islessequal:
6205                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6206                 break;
6207         case T___builtin_islessgreater:
6208                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6209                 break;
6210         case T___builtin_isunordered:
6211                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6212                 break;
6213         default:
6214                 internal_errorf(HERE, "invalid compare builtin found");
6215                 break;
6216         }
6217         expression->base.source_position = *HERE;
6218         next_token();
6219
6220         expect('(');
6221         expression->binary.left = parse_assignment_expression();
6222         expect(',');
6223         expression->binary.right = parse_assignment_expression();
6224         expect(')');
6225
6226         type_t *const orig_type_left  = expression->binary.left->base.type;
6227         type_t *const orig_type_right = expression->binary.right->base.type;
6228
6229         type_t *const type_left  = skip_typeref(orig_type_left);
6230         type_t *const type_right = skip_typeref(orig_type_right);
6231         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6232                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6233                         type_error_incompatible("invalid operands in comparison",
6234                                 &expression->base.source_position, orig_type_left, orig_type_right);
6235                 }
6236         } else {
6237                 semantic_comparison(&expression->binary);
6238         }
6239
6240         return expression;
6241 end_error:
6242         return create_invalid_expression();
6243 }
6244
6245 #if 0
6246 /**
6247  * Parses a __builtin_expect() expression.
6248  */
6249 static expression_t *parse_builtin_expect(void)
6250 {
6251         eat(T___builtin_expect);
6252
6253         expression_t *expression
6254                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
6255
6256         expect('(');
6257         expression->binary.left = parse_assignment_expression();
6258         expect(',');
6259         expression->binary.right = parse_constant_expression();
6260         expect(')');
6261
6262         expression->base.type = expression->binary.left->base.type;
6263
6264         return expression;
6265 end_error:
6266         return create_invalid_expression();
6267 }
6268 #endif
6269
6270 /**
6271  * Parses a MS assume() expression.
6272  */
6273 static expression_t *parse_assume(void)
6274 {
6275         eat(T__assume);
6276
6277         expression_t *expression
6278                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
6279
6280         expect('(');
6281         add_anchor_token(')');
6282         expression->unary.value = parse_assignment_expression();
6283         rem_anchor_token(')');
6284         expect(')');
6285
6286         expression->base.type = type_void;
6287         return expression;
6288 end_error:
6289         return create_invalid_expression();
6290 }
6291
6292 /**
6293  * Parse a microsoft __noop expression.
6294  */
6295 static expression_t *parse_noop_expression(void)
6296 {
6297         source_position_t source_position = *HERE;
6298         eat(T___noop);
6299
6300         if (token.type == '(') {
6301                 /* parse arguments */
6302                 eat('(');
6303                 add_anchor_token(')');
6304                 add_anchor_token(',');
6305
6306                 if (token.type != ')') {
6307                         while(true) {
6308                                 (void)parse_assignment_expression();
6309                                 if (token.type != ',')
6310                                         break;
6311                                 next_token();
6312                         }
6313                 }
6314         }
6315         rem_anchor_token(',');
6316         rem_anchor_token(')');
6317         expect(')');
6318
6319         /* the result is a (int)0 */
6320         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6321         cnst->base.source_position = source_position;
6322         cnst->base.type            = type_int;
6323         cnst->conste.v.int_value   = 0;
6324         cnst->conste.is_ms_noop    = true;
6325
6326         return cnst;
6327
6328 end_error:
6329         return create_invalid_expression();
6330 }
6331
6332 /**
6333  * Parses a primary expression.
6334  */
6335 static expression_t *parse_primary_expression(void)
6336 {
6337         switch (token.type) {
6338                 case T_INTEGER:                  return parse_int_const();
6339                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
6340                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
6341                 case T_FLOATINGPOINT:            return parse_float_const();
6342                 case T_STRING_LITERAL:
6343                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
6344                 case T_IDENTIFIER:               return parse_reference();
6345                 case T___FUNCTION__:
6346                 case T___func__:                 return parse_function_keyword();
6347                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
6348                 case T___FUNCSIG__:              return parse_funcsig_keyword();
6349                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
6350                 case T___builtin_offsetof:       return parse_offsetof();
6351                 case T___builtin_va_start:       return parse_va_start();
6352                 case T___builtin_va_arg:         return parse_va_arg();
6353                 case T___builtin_expect:
6354                 case T___builtin_alloca:
6355                 case T___builtin_nan:
6356                 case T___builtin_nand:
6357                 case T___builtin_nanf:
6358                 case T___builtin_huge_val:
6359                 case T___builtin_va_end:         return parse_builtin_symbol();
6360                 case T___builtin_isgreater:
6361                 case T___builtin_isgreaterequal:
6362                 case T___builtin_isless:
6363                 case T___builtin_islessequal:
6364                 case T___builtin_islessgreater:
6365                 case T___builtin_isunordered:    return parse_compare_builtin();
6366                 case T___builtin_constant_p:     return parse_builtin_constant();
6367                 case T___builtin_prefetch:       return parse_builtin_prefetch();
6368                 case T__assume:                  return parse_assume();
6369
6370                 case '(':                        return parse_brace_expression();
6371                 case T___noop:                   return parse_noop_expression();
6372         }
6373
6374         errorf(HERE, "unexpected token %K, expected an expression", &token);
6375         return create_invalid_expression();
6376 }
6377
6378 /**
6379  * Check if the expression has the character type and issue a warning then.
6380  */
6381 static void check_for_char_index_type(const expression_t *expression)
6382 {
6383         type_t       *const type      = expression->base.type;
6384         const type_t *const base_type = skip_typeref(type);
6385
6386         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
6387                         warning.char_subscripts) {
6388                 warningf(&expression->base.source_position,
6389                          "array subscript has type '%T'", type);
6390         }
6391 }
6392
6393 static expression_t *parse_array_expression(unsigned precedence,
6394                                             expression_t *left)
6395 {
6396         (void) precedence;
6397
6398         eat('[');
6399         add_anchor_token(']');
6400
6401         expression_t *inside = parse_expression();
6402
6403         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
6404
6405         array_access_expression_t *array_access = &expression->array_access;
6406
6407         type_t *const orig_type_left   = left->base.type;
6408         type_t *const orig_type_inside = inside->base.type;
6409
6410         type_t *const type_left   = skip_typeref(orig_type_left);
6411         type_t *const type_inside = skip_typeref(orig_type_inside);
6412
6413         type_t *return_type;
6414         if (is_type_pointer(type_left)) {
6415                 return_type             = type_left->pointer.points_to;
6416                 array_access->array_ref = left;
6417                 array_access->index     = inside;
6418                 check_for_char_index_type(inside);
6419         } else if (is_type_pointer(type_inside)) {
6420                 return_type             = type_inside->pointer.points_to;
6421                 array_access->array_ref = inside;
6422                 array_access->index     = left;
6423                 array_access->flipped   = true;
6424                 check_for_char_index_type(left);
6425         } else {
6426                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
6427                         errorf(HERE,
6428                                 "array access on object with non-pointer types '%T', '%T'",
6429                                 orig_type_left, orig_type_inside);
6430                 }
6431                 return_type             = type_error_type;
6432                 array_access->array_ref = create_invalid_expression();
6433         }
6434
6435         rem_anchor_token(']');
6436         if (token.type != ']') {
6437                 parse_error_expected("Problem while parsing array access", ']', NULL);
6438                 return expression;
6439         }
6440         next_token();
6441
6442         return_type           = automatic_type_conversion(return_type);
6443         expression->base.type = return_type;
6444
6445         return expression;
6446 }
6447
6448 static expression_t *parse_typeprop(expression_kind_t const kind,
6449                                     source_position_t const pos,
6450                                     unsigned const precedence)
6451 {
6452         expression_t *tp_expression = allocate_expression_zero(kind);
6453         tp_expression->base.type            = type_size_t;
6454         tp_expression->base.source_position = pos;
6455
6456         char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
6457
6458         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
6459                 next_token();
6460                 add_anchor_token(')');
6461                 type_t* const orig_type = parse_typename();
6462                 tp_expression->typeprop.type = orig_type;
6463
6464                 type_t const* const type = skip_typeref(orig_type);
6465                 char const* const wrong_type =
6466                         is_type_incomplete(type)    ? "incomplete"          :
6467                         type->kind == TYPE_FUNCTION ? "function designator" :
6468                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6469                         NULL;
6470                 if (wrong_type != NULL) {
6471                         errorf(&pos, "operand of %s expression must not be %s type '%T'",
6472                                what, wrong_type, type);
6473                 }
6474
6475                 rem_anchor_token(')');
6476                 expect(')');
6477         } else {
6478                 expression_t *expression = parse_sub_expression(precedence);
6479
6480                 type_t* const orig_type = revert_automatic_type_conversion(expression);
6481                 expression->base.type = orig_type;
6482
6483                 type_t const* const type = skip_typeref(orig_type);
6484                 char const* const wrong_type =
6485                         is_type_incomplete(type)    ? "incomplete"          :
6486                         type->kind == TYPE_FUNCTION ? "function designator" :
6487                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6488                         NULL;
6489                 if (wrong_type != NULL) {
6490                         errorf(&pos, "operand of %s expression must not be expression of %s type '%T'", what, wrong_type, type);
6491                 }
6492
6493                 tp_expression->typeprop.type          = expression->base.type;
6494                 tp_expression->typeprop.tp_expression = expression;
6495         }
6496
6497         return tp_expression;
6498 end_error:
6499         return create_invalid_expression();
6500 }
6501
6502 static expression_t *parse_sizeof(unsigned precedence)
6503 {
6504         source_position_t pos = *HERE;
6505         eat(T_sizeof);
6506         return parse_typeprop(EXPR_SIZEOF, pos, precedence);
6507 }
6508
6509 static expression_t *parse_alignof(unsigned precedence)
6510 {
6511         source_position_t pos = *HERE;
6512         eat(T___alignof__);
6513         return parse_typeprop(EXPR_ALIGNOF, pos, precedence);
6514 }
6515
6516 static expression_t *parse_select_expression(unsigned precedence,
6517                                              expression_t *compound)
6518 {
6519         (void) precedence;
6520         assert(token.type == '.' || token.type == T_MINUSGREATER);
6521
6522         bool is_pointer = (token.type == T_MINUSGREATER);
6523         next_token();
6524
6525         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
6526         select->select.compound = compound;
6527
6528         if (token.type != T_IDENTIFIER) {
6529                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
6530                 return select;
6531         }
6532         symbol_t *symbol      = token.v.symbol;
6533         select->select.symbol = symbol;
6534         next_token();
6535
6536         type_t *const orig_type = compound->base.type;
6537         type_t *const type      = skip_typeref(orig_type);
6538
6539         type_t *type_left = type;
6540         if (is_pointer) {
6541                 if (!is_type_pointer(type)) {
6542                         if (is_type_valid(type)) {
6543                                 errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
6544                         }
6545                         return create_invalid_expression();
6546                 }
6547                 type_left = type->pointer.points_to;
6548         }
6549         type_left = skip_typeref(type_left);
6550
6551         if (type_left->kind != TYPE_COMPOUND_STRUCT &&
6552             type_left->kind != TYPE_COMPOUND_UNION) {
6553                 if (is_type_valid(type_left)) {
6554                         errorf(HERE, "request for member '%Y' in something not a struct or "
6555                                "union, but '%T'", symbol, type_left);
6556                 }
6557                 return create_invalid_expression();
6558         }
6559
6560         declaration_t *const declaration = type_left->compound.declaration;
6561
6562         if (!declaration->init.complete) {
6563                 errorf(HERE, "request for member '%Y' of incomplete type '%T'",
6564                        symbol, type_left);
6565                 return create_invalid_expression();
6566         }
6567
6568         declaration_t *iter = find_compound_entry(declaration, symbol);
6569         if (iter == NULL) {
6570                 errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
6571                 return create_invalid_expression();
6572         }
6573
6574         /* we always do the auto-type conversions; the & and sizeof parser contains
6575          * code to revert this! */
6576         type_t *expression_type = automatic_type_conversion(iter->type);
6577
6578         select->select.compound_entry = iter;
6579         select->base.type             = expression_type;
6580
6581         type_t *skipped = skip_typeref(iter->type);
6582         if (skipped->kind == TYPE_BITFIELD) {
6583                 select->base.type = skipped->bitfield.base_type;
6584         }
6585
6586         return select;
6587 }
6588
6589 static void check_call_argument(const function_parameter_t *parameter,
6590                                 call_argument_t *argument)
6591 {
6592         type_t         *expected_type      = parameter->type;
6593         type_t         *expected_type_skip = skip_typeref(expected_type);
6594         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
6595         expression_t   *arg_expr           = argument->expression;
6596
6597         /* handle transparent union gnu extension */
6598         if (is_type_union(expected_type_skip)
6599                         && (expected_type_skip->base.modifiers
6600                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
6601                 declaration_t  *union_decl = expected_type_skip->compound.declaration;
6602
6603                 declaration_t *declaration = union_decl->scope.declarations;
6604                 type_t        *best_type   = NULL;
6605                 for ( ; declaration != NULL; declaration = declaration->next) {
6606                         type_t *decl_type = declaration->type;
6607                         error = semantic_assign(decl_type, arg_expr);
6608                         if (error == ASSIGN_ERROR_INCOMPATIBLE
6609                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
6610                                 continue;
6611
6612                         if (error == ASSIGN_SUCCESS) {
6613                                 best_type = decl_type;
6614                         } else if (best_type == NULL) {
6615                                 best_type = decl_type;
6616                         }
6617                 }
6618
6619                 if (best_type != NULL) {
6620                         expected_type = best_type;
6621                 }
6622         }
6623
6624         error                = semantic_assign(expected_type, arg_expr);
6625         argument->expression = create_implicit_cast(argument->expression,
6626                                                     expected_type);
6627
6628         /* TODO report exact scope in error messages (like "in 3rd parameter") */
6629         report_assign_error(error, expected_type, arg_expr,     "function call",
6630                             &arg_expr->base.source_position);
6631 }
6632
6633 /**
6634  * Parse a call expression, ie. expression '( ... )'.
6635  *
6636  * @param expression  the function address
6637  */
6638 static expression_t *parse_call_expression(unsigned precedence,
6639                                            expression_t *expression)
6640 {
6641         (void) precedence;
6642         expression_t *result = allocate_expression_zero(EXPR_CALL);
6643         result->base.source_position = expression->base.source_position;
6644
6645         call_expression_t *call = &result->call;
6646         call->function          = expression;
6647
6648         type_t *const orig_type = expression->base.type;
6649         type_t *const type      = skip_typeref(orig_type);
6650
6651         function_type_t *function_type = NULL;
6652         if (is_type_pointer(type)) {
6653                 type_t *const to_type = skip_typeref(type->pointer.points_to);
6654
6655                 if (is_type_function(to_type)) {
6656                         function_type   = &to_type->function;
6657                         call->base.type = function_type->return_type;
6658                 }
6659         }
6660
6661         if (function_type == NULL && is_type_valid(type)) {
6662                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
6663         }
6664
6665         /* parse arguments */
6666         eat('(');
6667         add_anchor_token(')');
6668         add_anchor_token(',');
6669
6670         if (token.type != ')') {
6671                 call_argument_t *last_argument = NULL;
6672
6673                 while(true) {
6674                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
6675
6676                         argument->expression = parse_assignment_expression();
6677                         if (last_argument == NULL) {
6678                                 call->arguments = argument;
6679                         } else {
6680                                 last_argument->next = argument;
6681                         }
6682                         last_argument = argument;
6683
6684                         if (token.type != ',')
6685                                 break;
6686                         next_token();
6687                 }
6688         }
6689         rem_anchor_token(',');
6690         rem_anchor_token(')');
6691         expect(')');
6692
6693         if (function_type == NULL)
6694                 return result;
6695
6696         function_parameter_t *parameter = function_type->parameters;
6697         call_argument_t      *argument  = call->arguments;
6698         if (!function_type->unspecified_parameters) {
6699                 for( ; parameter != NULL && argument != NULL;
6700                                 parameter = parameter->next, argument = argument->next) {
6701                         check_call_argument(parameter, argument);
6702                 }
6703
6704                 if (parameter != NULL) {
6705                         errorf(HERE, "too few arguments to function '%E'", expression);
6706                 } else if (argument != NULL && !function_type->variadic) {
6707                         errorf(HERE, "too many arguments to function '%E'", expression);
6708                 }
6709         }
6710
6711         /* do default promotion */
6712         for( ; argument != NULL; argument = argument->next) {
6713                 type_t *type = argument->expression->base.type;
6714
6715                 type = get_default_promoted_type(type);
6716
6717                 argument->expression
6718                         = create_implicit_cast(argument->expression, type);
6719         }
6720
6721         check_format(&result->call);
6722
6723         return result;
6724 end_error:
6725         return create_invalid_expression();
6726 }
6727
6728 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
6729
6730 static bool same_compound_type(const type_t *type1, const type_t *type2)
6731 {
6732         return
6733                 is_type_compound(type1) &&
6734                 type1->kind == type2->kind &&
6735                 type1->compound.declaration == type2->compound.declaration;
6736 }
6737
6738 /**
6739  * Parse a conditional expression, ie. 'expression ? ... : ...'.
6740  *
6741  * @param expression  the conditional expression
6742  */
6743 static expression_t *parse_conditional_expression(unsigned precedence,
6744                                                   expression_t *expression)
6745 {
6746         eat('?');
6747         add_anchor_token(':');
6748
6749         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
6750
6751         conditional_expression_t *conditional = &result->conditional;
6752         conditional->condition = expression;
6753
6754         /* 6.5.15.2 */
6755         type_t *const condition_type_orig = expression->base.type;
6756         type_t *const condition_type      = skip_typeref(condition_type_orig);
6757         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
6758                 type_error("expected a scalar type in conditional condition",
6759                            &expression->base.source_position, condition_type_orig);
6760         }
6761
6762         expression_t *true_expression = parse_expression();
6763         rem_anchor_token(':');
6764         expect(':');
6765         expression_t *false_expression = parse_sub_expression(precedence);
6766
6767         type_t *const orig_true_type  = true_expression->base.type;
6768         type_t *const orig_false_type = false_expression->base.type;
6769         type_t *const true_type       = skip_typeref(orig_true_type);
6770         type_t *const false_type      = skip_typeref(orig_false_type);
6771
6772         /* 6.5.15.3 */
6773         type_t *result_type;
6774         if (is_type_atomic(true_type, ATOMIC_TYPE_VOID) ||
6775                 is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
6776                 if (!is_type_atomic(true_type, ATOMIC_TYPE_VOID)
6777                     || !is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
6778                         warningf(&expression->base.source_position,
6779                                         "ISO C forbids conditional expression with only one void side");
6780                 }
6781                 result_type = type_void;
6782         } else if (is_type_arithmetic(true_type)
6783                    && is_type_arithmetic(false_type)) {
6784                 result_type = semantic_arithmetic(true_type, false_type);
6785
6786                 true_expression  = create_implicit_cast(true_expression, result_type);
6787                 false_expression = create_implicit_cast(false_expression, result_type);
6788
6789                 conditional->true_expression  = true_expression;
6790                 conditional->false_expression = false_expression;
6791                 conditional->base.type        = result_type;
6792         } else if (same_compound_type(true_type, false_type)) {
6793                 /* just take 1 of the 2 types */
6794                 result_type = true_type;
6795         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
6796                 type_t *pointer_type;
6797                 type_t *other_type;
6798                 expression_t *other_expression;
6799                 if (is_type_pointer(true_type) &&
6800                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
6801                         pointer_type     = true_type;
6802                         other_type       = false_type;
6803                         other_expression = false_expression;
6804                 } else {
6805                         pointer_type     = false_type;
6806                         other_type       = true_type;
6807                         other_expression = true_expression;
6808                 }
6809
6810                 if (is_null_pointer_constant(other_expression)) {
6811                         result_type = pointer_type;
6812                 } else if (is_type_pointer(other_type)) {
6813                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
6814                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
6815
6816                         type_t *to;
6817                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
6818                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
6819                                 to = type_void;
6820                         } else if (types_compatible(get_unqualified_type(to1),
6821                                                     get_unqualified_type(to2))) {
6822                                 to = to1;
6823                         } else {
6824                                 warningf(&expression->base.source_position,
6825                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
6826                                         true_type, false_type);
6827                                 to = type_void;
6828                         }
6829
6830                         type_t *const copy = duplicate_type(to);
6831                         copy->base.qualifiers = to1->base.qualifiers | to2->base.qualifiers;
6832
6833                         type_t *const type = typehash_insert(copy);
6834                         if (type != copy)
6835                                 free_type(copy);
6836
6837                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
6838                 } else if (is_type_integer(other_type)) {
6839                         warningf(&expression->base.source_position,
6840                                         "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
6841                         result_type = pointer_type;
6842                 } else {
6843                         type_error_incompatible("while parsing conditional",
6844                                         &expression->base.source_position, true_type, false_type);
6845                         result_type = type_error_type;
6846                 }
6847         } else {
6848                 /* TODO: one pointer to void*, other some pointer */
6849
6850                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
6851                         type_error_incompatible("while parsing conditional",
6852                                                 &expression->base.source_position, true_type,
6853                                                 false_type);
6854                 }
6855                 result_type = type_error_type;
6856         }
6857
6858         conditional->true_expression
6859                 = create_implicit_cast(true_expression, result_type);
6860         conditional->false_expression
6861                 = create_implicit_cast(false_expression, result_type);
6862         conditional->base.type = result_type;
6863         return result;
6864 end_error:
6865         return create_invalid_expression();
6866 }
6867
6868 /**
6869  * Parse an extension expression.
6870  */
6871 static expression_t *parse_extension(unsigned precedence)
6872 {
6873         eat(T___extension__);
6874
6875         /* TODO enable extensions */
6876         expression_t *expression = parse_sub_expression(precedence);
6877         /* TODO disable extensions */
6878         return expression;
6879 }
6880
6881 /**
6882  * Parse a __builtin_classify_type() expression.
6883  */
6884 static expression_t *parse_builtin_classify_type(const unsigned precedence)
6885 {
6886         eat(T___builtin_classify_type);
6887
6888         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
6889         result->base.type    = type_int;
6890
6891         expect('(');
6892         add_anchor_token(')');
6893         expression_t *expression = parse_sub_expression(precedence);
6894         rem_anchor_token(')');
6895         expect(')');
6896         result->classify_type.type_expression = expression;
6897
6898         return result;
6899 end_error:
6900         return create_invalid_expression();
6901 }
6902
6903 static void check_pointer_arithmetic(const source_position_t *source_position,
6904                                      type_t *pointer_type,
6905                                      type_t *orig_pointer_type)
6906 {
6907         type_t *points_to = pointer_type->pointer.points_to;
6908         points_to = skip_typeref(points_to);
6909
6910         if (is_type_incomplete(points_to) &&
6911                         (! (c_mode & _GNUC)
6912                          || !is_type_atomic(points_to, ATOMIC_TYPE_VOID))) {
6913                 errorf(source_position,
6914                            "arithmetic with pointer to incomplete type '%T' not allowed",
6915                            orig_pointer_type);
6916         } else if (is_type_function(points_to)) {
6917                 errorf(source_position,
6918                            "arithmetic with pointer to function type '%T' not allowed",
6919                            orig_pointer_type);
6920         }
6921 }
6922
6923 static void semantic_incdec(unary_expression_t *expression)
6924 {
6925         type_t *const orig_type = expression->value->base.type;
6926         type_t *const type      = skip_typeref(orig_type);
6927         if (is_type_pointer(type)) {
6928                 check_pointer_arithmetic(&expression->base.source_position,
6929                                          type, orig_type);
6930         } else if (!is_type_real(type) && is_type_valid(type)) {
6931                 /* TODO: improve error message */
6932                 errorf(HERE, "operation needs an arithmetic or pointer type");
6933         }
6934         expression->base.type = orig_type;
6935 }
6936
6937 static void semantic_unexpr_arithmetic(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_arithmetic(type)) {
6942                 if (is_type_valid(type)) {
6943                         /* TODO: improve error message */
6944                         errorf(HERE, "operation needs an arithmetic type");
6945                 }
6946                 return;
6947         }
6948
6949         expression->base.type = orig_type;
6950 }
6951
6952 static void semantic_unexpr_scalar(unary_expression_t *expression)
6953 {
6954         type_t *const orig_type = expression->value->base.type;
6955         type_t *const type      = skip_typeref(orig_type);
6956         if (!is_type_scalar(type)) {
6957                 if (is_type_valid(type)) {
6958                         errorf(HERE, "operand of ! must be of scalar type");
6959                 }
6960                 return;
6961         }
6962
6963         expression->base.type = orig_type;
6964 }
6965
6966 static void semantic_unexpr_integer(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_integer(type)) {
6971                 if (is_type_valid(type)) {
6972                         errorf(HERE, "operand of ~ must be of integer type");
6973                 }
6974                 return;
6975         }
6976
6977         expression->base.type = orig_type;
6978 }
6979
6980 static void semantic_dereference(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_pointer(type)) {
6985                 if (is_type_valid(type)) {
6986                         errorf(HERE, "Unary '*' needs pointer or arrray type, but type '%T' given", orig_type);
6987                 }
6988                 return;
6989         }
6990
6991         type_t *result_type   = type->pointer.points_to;
6992         result_type           = automatic_type_conversion(result_type);
6993         expression->base.type = result_type;
6994 }
6995
6996 static void set_address_taken(expression_t *expression, bool may_be_register)
6997 {
6998         if (expression->kind != EXPR_REFERENCE)
6999                 return;
7000
7001         declaration_t *const declaration = expression->reference.declaration;
7002         /* happens for parse errors */
7003         if (declaration == NULL)
7004                 return;
7005
7006         if (declaration->storage_class == STORAGE_CLASS_REGISTER && !may_be_register) {
7007                 errorf(&expression->base.source_position,
7008                                 "address of register variable '%Y' requested",
7009                                 declaration->symbol);
7010         } else {
7011                 declaration->address_taken = 1;
7012         }
7013 }
7014
7015 /**
7016  * Check the semantic of the address taken expression.
7017  */
7018 static void semantic_take_addr(unary_expression_t *expression)
7019 {
7020         expression_t *value = expression->value;
7021         value->base.type    = revert_automatic_type_conversion(value);
7022
7023         type_t *orig_type = value->base.type;
7024         if (!is_type_valid(orig_type))
7025                 return;
7026
7027         set_address_taken(value, false);
7028
7029         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
7030 }
7031
7032 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc)   \
7033 static expression_t *parse_##unexpression_type(unsigned precedence)            \
7034 {                                                                              \
7035         eat(token_type);                                                           \
7036                                                                                    \
7037         expression_t *unary_expression                                             \
7038                 = allocate_expression_zero(unexpression_type);                         \
7039         unary_expression->base.source_position = *HERE;                            \
7040         unary_expression->unary.value = parse_sub_expression(precedence);          \
7041                                                                                    \
7042         sfunc(&unary_expression->unary);                                           \
7043                                                                                    \
7044         return unary_expression;                                                   \
7045 }
7046
7047 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
7048                                semantic_unexpr_arithmetic)
7049 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
7050                                semantic_unexpr_arithmetic)
7051 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
7052                                semantic_unexpr_scalar)
7053 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
7054                                semantic_dereference)
7055 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
7056                                semantic_take_addr)
7057 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
7058                                semantic_unexpr_integer)
7059 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
7060                                semantic_incdec)
7061 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
7062                                semantic_incdec)
7063
7064 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
7065                                                sfunc)                         \
7066 static expression_t *parse_##unexpression_type(unsigned precedence,           \
7067                                                expression_t *left)            \
7068 {                                                                             \
7069         (void) precedence;                                                        \
7070         eat(token_type);                                                          \
7071                                                                               \
7072         expression_t *unary_expression                                            \
7073                 = allocate_expression_zero(unexpression_type);                        \
7074         unary_expression->unary.value = left;                                     \
7075                                                                                   \
7076         sfunc(&unary_expression->unary);                                          \
7077                                                                               \
7078         return unary_expression;                                                  \
7079 }
7080
7081 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
7082                                        EXPR_UNARY_POSTFIX_INCREMENT,
7083                                        semantic_incdec)
7084 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
7085                                        EXPR_UNARY_POSTFIX_DECREMENT,
7086                                        semantic_incdec)
7087
7088 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
7089 {
7090         /* TODO: handle complex + imaginary types */
7091
7092         /* § 6.3.1.8 Usual arithmetic conversions */
7093         if (type_left == type_long_double || type_right == type_long_double) {
7094                 return type_long_double;
7095         } else if (type_left == type_double || type_right == type_double) {
7096                 return type_double;
7097         } else if (type_left == type_float || type_right == type_float) {
7098                 return type_float;
7099         }
7100
7101         type_left  = promote_integer(type_left);
7102         type_right = promote_integer(type_right);
7103
7104         if (type_left == type_right)
7105                 return type_left;
7106
7107         bool const signed_left  = is_type_signed(type_left);
7108         bool const signed_right = is_type_signed(type_right);
7109         int  const rank_left    = get_rank(type_left);
7110         int  const rank_right   = get_rank(type_right);
7111
7112         if (signed_left == signed_right)
7113                 return rank_left >= rank_right ? type_left : type_right;
7114
7115         int     s_rank;
7116         int     u_rank;
7117         type_t *s_type;
7118         type_t *u_type;
7119         if (signed_left) {
7120                 s_rank = rank_left;
7121                 s_type = type_left;
7122                 u_rank = rank_right;
7123                 u_type = type_right;
7124         } else {
7125                 s_rank = rank_right;
7126                 s_type = type_right;
7127                 u_rank = rank_left;
7128                 u_type = type_left;
7129         }
7130
7131         if (u_rank >= s_rank)
7132                 return u_type;
7133
7134         if (get_atomic_type_size(s_rank) > get_atomic_type_size(u_rank))
7135                 return s_type;
7136
7137         /* FIXME ugly */
7138         type_t *const type = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
7139         switch (s_rank) {
7140                 case ATOMIC_TYPE_INT:      type->atomic.akind = ATOMIC_TYPE_UINT;      break;
7141                 case ATOMIC_TYPE_LONG:     type->atomic.akind = ATOMIC_TYPE_ULONG;     break;
7142                 case ATOMIC_TYPE_LONGLONG: type->atomic.akind = ATOMIC_TYPE_ULONGLONG; break;
7143
7144                 default: panic("invalid atomic type");
7145         }
7146
7147         type_t* const result = typehash_insert(type);
7148         if (result != type)
7149                 free_type(type);
7150
7151         return result;
7152 }
7153
7154 /**
7155  * Check the semantic restrictions for a binary expression.
7156  */
7157 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
7158 {
7159         expression_t *const left            = expression->left;
7160         expression_t *const right           = expression->right;
7161         type_t       *const orig_type_left  = left->base.type;
7162         type_t       *const orig_type_right = right->base.type;
7163         type_t       *const type_left       = skip_typeref(orig_type_left);
7164         type_t       *const type_right      = skip_typeref(orig_type_right);
7165
7166         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7167                 /* TODO: improve error message */
7168                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7169                         errorf(HERE, "operation needs arithmetic types");
7170                 }
7171                 return;
7172         }
7173
7174         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7175         expression->left      = create_implicit_cast(left, arithmetic_type);
7176         expression->right     = create_implicit_cast(right, arithmetic_type);
7177         expression->base.type = arithmetic_type;
7178 }
7179
7180 static void semantic_shift_op(binary_expression_t *expression)
7181 {
7182         expression_t *const left            = expression->left;
7183         expression_t *const right           = expression->right;
7184         type_t       *const orig_type_left  = left->base.type;
7185         type_t       *const orig_type_right = right->base.type;
7186         type_t       *      type_left       = skip_typeref(orig_type_left);
7187         type_t       *      type_right      = skip_typeref(orig_type_right);
7188
7189         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
7190                 /* TODO: improve error message */
7191                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7192                         errorf(HERE, "operation needs integer types");
7193                 }
7194                 return;
7195         }
7196
7197         type_left  = promote_integer(type_left);
7198         type_right = promote_integer(type_right);
7199
7200         expression->left      = create_implicit_cast(left, type_left);
7201         expression->right     = create_implicit_cast(right, type_right);
7202         expression->base.type = type_left;
7203 }
7204
7205 static void semantic_add(binary_expression_t *expression)
7206 {
7207         expression_t *const left            = expression->left;
7208         expression_t *const right           = expression->right;
7209         type_t       *const orig_type_left  = left->base.type;
7210         type_t       *const orig_type_right = right->base.type;
7211         type_t       *const type_left       = skip_typeref(orig_type_left);
7212         type_t       *const type_right      = skip_typeref(orig_type_right);
7213
7214         /* § 6.5.6 */
7215         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7216                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7217                 expression->left  = create_implicit_cast(left, arithmetic_type);
7218                 expression->right = create_implicit_cast(right, arithmetic_type);
7219                 expression->base.type = arithmetic_type;
7220                 return;
7221         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7222                 check_pointer_arithmetic(&expression->base.source_position,
7223                                          type_left, orig_type_left);
7224                 expression->base.type = type_left;
7225         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
7226                 check_pointer_arithmetic(&expression->base.source_position,
7227                                          type_right, orig_type_right);
7228                 expression->base.type = type_right;
7229         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7230                 errorf(&expression->base.source_position,
7231                        "invalid operands to binary + ('%T', '%T')",
7232                        orig_type_left, orig_type_right);
7233         }
7234 }
7235
7236 static void semantic_sub(binary_expression_t *expression)
7237 {
7238         expression_t *const left            = expression->left;
7239         expression_t *const right           = expression->right;
7240         type_t       *const orig_type_left  = left->base.type;
7241         type_t       *const orig_type_right = right->base.type;
7242         type_t       *const type_left       = skip_typeref(orig_type_left);
7243         type_t       *const type_right      = skip_typeref(orig_type_right);
7244
7245         /* § 5.6.5 */
7246         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7247                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7248                 expression->left        = create_implicit_cast(left, arithmetic_type);
7249                 expression->right       = create_implicit_cast(right, arithmetic_type);
7250                 expression->base.type =  arithmetic_type;
7251                 return;
7252         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7253                 check_pointer_arithmetic(&expression->base.source_position,
7254                                          type_left, orig_type_left);
7255                 expression->base.type = type_left;
7256         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7257                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
7258                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
7259                 if (!types_compatible(unqual_left, unqual_right)) {
7260                         errorf(&expression->base.source_position,
7261                                "subtracting pointers to incompatible types '%T' and '%T'",
7262                                orig_type_left, orig_type_right);
7263                 } else if (!is_type_object(unqual_left)) {
7264                         if (is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
7265                                 warningf(&expression->base.source_position,
7266                                          "subtracting pointers to void");
7267                         } else {
7268                                 errorf(&expression->base.source_position,
7269                                        "subtracting pointers to non-object types '%T'",
7270                                        orig_type_left);
7271                         }
7272                 }
7273                 expression->base.type = type_ptrdiff_t;
7274         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7275                 errorf(HERE, "invalid operands of types '%T' and '%T' to binary '-'",
7276                        orig_type_left, orig_type_right);
7277         }
7278 }
7279
7280 /**
7281  * Check the semantics of comparison expressions.
7282  *
7283  * @param expression   The expression to check.
7284  */
7285 static void semantic_comparison(binary_expression_t *expression)
7286 {
7287         expression_t *left            = expression->left;
7288         expression_t *right           = expression->right;
7289         type_t       *orig_type_left  = left->base.type;
7290         type_t       *orig_type_right = right->base.type;
7291
7292         type_t *type_left  = skip_typeref(orig_type_left);
7293         type_t *type_right = skip_typeref(orig_type_right);
7294
7295         /* TODO non-arithmetic types */
7296         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7297                 /* test for signed vs unsigned compares */
7298                 if (warning.sign_compare &&
7299                     (expression->base.kind != EXPR_BINARY_EQUAL &&
7300                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
7301                     (is_type_signed(type_left) != is_type_signed(type_right))) {
7302
7303                         /* check if 1 of the operands is a constant, in this case we just
7304                          * check wether we can safely represent the resulting constant in
7305                          * the type of the other operand. */
7306                         expression_t *const_expr = NULL;
7307                         expression_t *other_expr = NULL;
7308
7309                         if (is_constant_expression(left)) {
7310                                 const_expr = left;
7311                                 other_expr = right;
7312                         } else if (is_constant_expression(right)) {
7313                                 const_expr = right;
7314                                 other_expr = left;
7315                         }
7316
7317                         if (const_expr != NULL) {
7318                                 type_t *other_type = skip_typeref(other_expr->base.type);
7319                                 long    val        = fold_constant(const_expr);
7320                                 /* TODO: check if val can be represented by other_type */
7321                                 (void) other_type;
7322                                 (void) val;
7323                         }
7324                         warningf(&expression->base.source_position,
7325                                  "comparison between signed and unsigned");
7326                 }
7327                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7328                 expression->left        = create_implicit_cast(left, arithmetic_type);
7329                 expression->right       = create_implicit_cast(right, arithmetic_type);
7330                 expression->base.type   = arithmetic_type;
7331                 if (warning.float_equal &&
7332                     (expression->base.kind == EXPR_BINARY_EQUAL ||
7333                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
7334                     is_type_float(arithmetic_type)) {
7335                         warningf(&expression->base.source_position,
7336                                  "comparing floating point with == or != is unsafe");
7337                 }
7338         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7339                 /* TODO check compatibility */
7340         } else if (is_type_pointer(type_left)) {
7341                 expression->right = create_implicit_cast(right, type_left);
7342         } else if (is_type_pointer(type_right)) {
7343                 expression->left = create_implicit_cast(left, type_right);
7344         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7345                 type_error_incompatible("invalid operands in comparison",
7346                                         &expression->base.source_position,
7347                                         type_left, type_right);
7348         }
7349         expression->base.type = type_int;
7350 }
7351
7352 /**
7353  * Checks if a compound type has constant fields.
7354  */
7355 static bool has_const_fields(const compound_type_t *type)
7356 {
7357         const scope_t       *scope       = &type->declaration->scope;
7358         const declaration_t *declaration = scope->declarations;
7359
7360         for (; declaration != NULL; declaration = declaration->next) {
7361                 if (declaration->namespc != NAMESPACE_NORMAL)
7362                         continue;
7363
7364                 const type_t *decl_type = skip_typeref(declaration->type);
7365                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
7366                         return true;
7367         }
7368         /* TODO */
7369         return false;
7370 }
7371
7372 static bool is_lvalue(const expression_t *expression)
7373 {
7374         switch (expression->kind) {
7375         case EXPR_REFERENCE:
7376         case EXPR_ARRAY_ACCESS:
7377         case EXPR_SELECT:
7378         case EXPR_UNARY_DEREFERENCE:
7379                 return true;
7380
7381         default:
7382                 return false;
7383         }
7384 }
7385
7386 static bool is_valid_assignment_lhs(expression_t const* const left)
7387 {
7388         type_t *const orig_type_left = revert_automatic_type_conversion(left);
7389         type_t *const type_left      = skip_typeref(orig_type_left);
7390
7391         if (!is_lvalue(left)) {
7392                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
7393                        left);
7394                 return false;
7395         }
7396
7397         if (is_type_array(type_left)) {
7398                 errorf(HERE, "cannot assign to arrays ('%E')", left);
7399                 return false;
7400         }
7401         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
7402                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
7403                        orig_type_left);
7404                 return false;
7405         }
7406         if (is_type_incomplete(type_left)) {
7407                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
7408                        left, orig_type_left);
7409                 return false;
7410         }
7411         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
7412                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
7413                        left, orig_type_left);
7414                 return false;
7415         }
7416
7417         return true;
7418 }
7419
7420 static void semantic_arithmetic_assign(binary_expression_t *expression)
7421 {
7422         expression_t *left            = expression->left;
7423         expression_t *right           = expression->right;
7424         type_t       *orig_type_left  = left->base.type;
7425         type_t       *orig_type_right = right->base.type;
7426
7427         if (!is_valid_assignment_lhs(left))
7428                 return;
7429
7430         type_t *type_left  = skip_typeref(orig_type_left);
7431         type_t *type_right = skip_typeref(orig_type_right);
7432
7433         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7434                 /* TODO: improve error message */
7435                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7436                         errorf(HERE, "operation needs arithmetic types");
7437                 }
7438                 return;
7439         }
7440
7441         /* combined instructions are tricky. We can't create an implicit cast on
7442          * the left side, because we need the uncasted form for the store.
7443          * The ast2firm pass has to know that left_type must be right_type
7444          * for the arithmetic operation and create a cast by itself */
7445         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7446         expression->right       = create_implicit_cast(right, arithmetic_type);
7447         expression->base.type   = type_left;
7448 }
7449
7450 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
7451 {
7452         expression_t *const left            = expression->left;
7453         expression_t *const right           = expression->right;
7454         type_t       *const orig_type_left  = left->base.type;
7455         type_t       *const orig_type_right = right->base.type;
7456         type_t       *const type_left       = skip_typeref(orig_type_left);
7457         type_t       *const type_right      = skip_typeref(orig_type_right);
7458
7459         if (!is_valid_assignment_lhs(left))
7460                 return;
7461
7462         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7463                 /* combined instructions are tricky. We can't create an implicit cast on
7464                  * the left side, because we need the uncasted form for the store.
7465                  * The ast2firm pass has to know that left_type must be right_type
7466                  * for the arithmetic operation and create a cast by itself */
7467                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
7468                 expression->right     = create_implicit_cast(right, arithmetic_type);
7469                 expression->base.type = type_left;
7470         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7471                 check_pointer_arithmetic(&expression->base.source_position,
7472                                          type_left, orig_type_left);
7473                 expression->base.type = type_left;
7474         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7475                 errorf(HERE, "incompatible types '%T' and '%T' in assignment", orig_type_left, orig_type_right);
7476         }
7477 }
7478
7479 /**
7480  * Check the semantic restrictions of a logical expression.
7481  */
7482 static void semantic_logical_op(binary_expression_t *expression)
7483 {
7484         expression_t *const left            = expression->left;
7485         expression_t *const right           = expression->right;
7486         type_t       *const orig_type_left  = left->base.type;
7487         type_t       *const orig_type_right = right->base.type;
7488         type_t       *const type_left       = skip_typeref(orig_type_left);
7489         type_t       *const type_right      = skip_typeref(orig_type_right);
7490
7491         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
7492                 /* TODO: improve error message */
7493                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7494                         errorf(HERE, "operation needs scalar types");
7495                 }
7496                 return;
7497         }
7498
7499         expression->base.type = type_int;
7500 }
7501
7502 /**
7503  * Check the semantic restrictions of a binary assign expression.
7504  */
7505 static void semantic_binexpr_assign(binary_expression_t *expression)
7506 {
7507         expression_t *left           = expression->left;
7508         type_t       *orig_type_left = left->base.type;
7509
7510         type_t *type_left = revert_automatic_type_conversion(left);
7511         type_left         = skip_typeref(orig_type_left);
7512
7513         if (!is_valid_assignment_lhs(left))
7514                 return;
7515
7516         assign_error_t error = semantic_assign(orig_type_left, expression->right);
7517         report_assign_error(error, orig_type_left, expression->right,
7518                         "assignment", &left->base.source_position);
7519         expression->right = create_implicit_cast(expression->right, orig_type_left);
7520         expression->base.type = orig_type_left;
7521 }
7522
7523 /**
7524  * Determine if the outermost operation (or parts thereof) of the given
7525  * expression has no effect in order to generate a warning about this fact.
7526  * Therefore in some cases this only examines some of the operands of the
7527  * expression (see comments in the function and examples below).
7528  * Examples:
7529  *   f() + 23;    // warning, because + has no effect
7530  *   x || f();    // no warning, because x controls execution of f()
7531  *   x ? y : f(); // warning, because y has no effect
7532  *   (void)x;     // no warning to be able to suppress the warning
7533  * This function can NOT be used for an "expression has definitely no effect"-
7534  * analysis. */
7535 static bool expression_has_effect(const expression_t *const expr)
7536 {
7537         switch (expr->kind) {
7538                 case EXPR_UNKNOWN:                   break;
7539                 case EXPR_INVALID:                   return true; /* do NOT warn */
7540                 case EXPR_REFERENCE:                 return false;
7541                 /* suppress the warning for microsoft __noop operations */
7542                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
7543                 case EXPR_CHARACTER_CONSTANT:        return false;
7544                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
7545                 case EXPR_STRING_LITERAL:            return false;
7546                 case EXPR_WIDE_STRING_LITERAL:       return false;
7547
7548                 case EXPR_CALL: {
7549                         const call_expression_t *const call = &expr->call;
7550                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
7551                                 return true;
7552
7553                         switch (call->function->builtin_symbol.symbol->ID) {
7554                                 case T___builtin_va_end: return true;
7555                                 default:                 return false;
7556                         }
7557                 }
7558
7559                 /* Generate the warning if either the left or right hand side of a
7560                  * conditional expression has no effect */
7561                 case EXPR_CONDITIONAL: {
7562                         const conditional_expression_t *const cond = &expr->conditional;
7563                         return
7564                                 expression_has_effect(cond->true_expression) &&
7565                                 expression_has_effect(cond->false_expression);
7566                 }
7567
7568                 case EXPR_SELECT:                    return false;
7569                 case EXPR_ARRAY_ACCESS:              return false;
7570                 case EXPR_SIZEOF:                    return false;
7571                 case EXPR_CLASSIFY_TYPE:             return false;
7572                 case EXPR_ALIGNOF:                   return false;
7573
7574                 case EXPR_FUNCNAME:                  return false;
7575                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
7576                 case EXPR_BUILTIN_CONSTANT_P:        return false;
7577                 case EXPR_BUILTIN_PREFETCH:          return true;
7578                 case EXPR_OFFSETOF:                  return false;
7579                 case EXPR_VA_START:                  return true;
7580                 case EXPR_VA_ARG:                    return true;
7581                 case EXPR_STATEMENT:                 return true; // TODO
7582                 case EXPR_COMPOUND_LITERAL:          return false;
7583
7584                 case EXPR_UNARY_NEGATE:              return false;
7585                 case EXPR_UNARY_PLUS:                return false;
7586                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
7587                 case EXPR_UNARY_NOT:                 return false;
7588                 case EXPR_UNARY_DEREFERENCE:         return false;
7589                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
7590                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
7591                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
7592                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
7593                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
7594
7595                 /* Treat void casts as if they have an effect in order to being able to
7596                  * suppress the warning */
7597                 case EXPR_UNARY_CAST: {
7598                         type_t *const type = skip_typeref(expr->base.type);
7599                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
7600                 }
7601
7602                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
7603                 case EXPR_UNARY_ASSUME:              return true;
7604
7605                 case EXPR_BINARY_ADD:                return false;
7606                 case EXPR_BINARY_SUB:                return false;
7607                 case EXPR_BINARY_MUL:                return false;
7608                 case EXPR_BINARY_DIV:                return false;
7609                 case EXPR_BINARY_MOD:                return false;
7610                 case EXPR_BINARY_EQUAL:              return false;
7611                 case EXPR_BINARY_NOTEQUAL:           return false;
7612                 case EXPR_BINARY_LESS:               return false;
7613                 case EXPR_BINARY_LESSEQUAL:          return false;
7614                 case EXPR_BINARY_GREATER:            return false;
7615                 case EXPR_BINARY_GREATEREQUAL:       return false;
7616                 case EXPR_BINARY_BITWISE_AND:        return false;
7617                 case EXPR_BINARY_BITWISE_OR:         return false;
7618                 case EXPR_BINARY_BITWISE_XOR:        return false;
7619                 case EXPR_BINARY_SHIFTLEFT:          return false;
7620                 case EXPR_BINARY_SHIFTRIGHT:         return false;
7621                 case EXPR_BINARY_ASSIGN:             return true;
7622                 case EXPR_BINARY_MUL_ASSIGN:         return true;
7623                 case EXPR_BINARY_DIV_ASSIGN:         return true;
7624                 case EXPR_BINARY_MOD_ASSIGN:         return true;
7625                 case EXPR_BINARY_ADD_ASSIGN:         return true;
7626                 case EXPR_BINARY_SUB_ASSIGN:         return true;
7627                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
7628                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
7629                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
7630                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
7631                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
7632
7633                 /* Only examine the right hand side of && and ||, because the left hand
7634                  * side already has the effect of controlling the execution of the right
7635                  * hand side */
7636                 case EXPR_BINARY_LOGICAL_AND:
7637                 case EXPR_BINARY_LOGICAL_OR:
7638                 /* Only examine the right hand side of a comma expression, because the left
7639                  * hand side has a separate warning */
7640                 case EXPR_BINARY_COMMA:
7641                         return expression_has_effect(expr->binary.right);
7642
7643                 case EXPR_BINARY_BUILTIN_EXPECT:     return true;
7644                 case EXPR_BINARY_ISGREATER:          return false;
7645                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
7646                 case EXPR_BINARY_ISLESS:             return false;
7647                 case EXPR_BINARY_ISLESSEQUAL:        return false;
7648                 case EXPR_BINARY_ISLESSGREATER:      return false;
7649                 case EXPR_BINARY_ISUNORDERED:        return false;
7650         }
7651
7652         internal_errorf(HERE, "unexpected expression");
7653 }
7654
7655 static void semantic_comma(binary_expression_t *expression)
7656 {
7657         if (warning.unused_value) {
7658                 const expression_t *const left = expression->left;
7659                 if (!expression_has_effect(left)) {
7660                         warningf(&left->base.source_position,
7661                                  "left-hand operand of comma expression has no effect");
7662                 }
7663         }
7664         expression->base.type = expression->right->base.type;
7665 }
7666
7667 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr)  \
7668 static expression_t *parse_##binexpression_type(unsigned precedence,      \
7669                                                 expression_t *left)       \
7670 {                                                                         \
7671         eat(token_type);                                                      \
7672         source_position_t pos = *HERE;                                        \
7673                                                                           \
7674         expression_t *right = parse_sub_expression(precedence + lr);          \
7675                                                                           \
7676         expression_t *binexpr = allocate_expression_zero(binexpression_type); \
7677         binexpr->base.source_position = pos;                                  \
7678         binexpr->binary.left  = left;                                         \
7679         binexpr->binary.right = right;                                        \
7680         sfunc(&binexpr->binary);                                              \
7681                                                                           \
7682         return binexpr;                                                       \
7683 }
7684
7685 CREATE_BINEXPR_PARSER(',', EXPR_BINARY_COMMA,    semantic_comma, 1)
7686 CREATE_BINEXPR_PARSER('*', EXPR_BINARY_MUL,      semantic_binexpr_arithmetic, 1)
7687 CREATE_BINEXPR_PARSER('/', EXPR_BINARY_DIV,      semantic_binexpr_arithmetic, 1)
7688 CREATE_BINEXPR_PARSER('%', EXPR_BINARY_MOD,      semantic_binexpr_arithmetic, 1)
7689 CREATE_BINEXPR_PARSER('+', EXPR_BINARY_ADD,      semantic_add, 1)
7690 CREATE_BINEXPR_PARSER('-', EXPR_BINARY_SUB,      semantic_sub, 1)
7691 CREATE_BINEXPR_PARSER('<', EXPR_BINARY_LESS,     semantic_comparison, 1)
7692 CREATE_BINEXPR_PARSER('>', EXPR_BINARY_GREATER,  semantic_comparison, 1)
7693 CREATE_BINEXPR_PARSER('=', EXPR_BINARY_ASSIGN,   semantic_binexpr_assign, 0)
7694
7695 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,
7696                       semantic_comparison, 1)
7697 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,
7698                       semantic_comparison, 1)
7699 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,
7700                       semantic_comparison, 1)
7701 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,
7702                       semantic_comparison, 1)
7703
7704 CREATE_BINEXPR_PARSER('&', EXPR_BINARY_BITWISE_AND,
7705                       semantic_binexpr_arithmetic, 1)
7706 CREATE_BINEXPR_PARSER('|', EXPR_BINARY_BITWISE_OR,
7707                       semantic_binexpr_arithmetic, 1)
7708 CREATE_BINEXPR_PARSER('^', EXPR_BINARY_BITWISE_XOR,
7709                       semantic_binexpr_arithmetic, 1)
7710 CREATE_BINEXPR_PARSER(T_ANDAND, EXPR_BINARY_LOGICAL_AND,
7711                       semantic_logical_op, 1)
7712 CREATE_BINEXPR_PARSER(T_PIPEPIPE, EXPR_BINARY_LOGICAL_OR,
7713                       semantic_logical_op, 1)
7714 CREATE_BINEXPR_PARSER(T_LESSLESS, EXPR_BINARY_SHIFTLEFT,
7715                       semantic_shift_op, 1)
7716 CREATE_BINEXPR_PARSER(T_GREATERGREATER, EXPR_BINARY_SHIFTRIGHT,
7717                       semantic_shift_op, 1)
7718 CREATE_BINEXPR_PARSER(T_PLUSEQUAL, EXPR_BINARY_ADD_ASSIGN,
7719                       semantic_arithmetic_addsubb_assign, 0)
7720 CREATE_BINEXPR_PARSER(T_MINUSEQUAL, EXPR_BINARY_SUB_ASSIGN,
7721                       semantic_arithmetic_addsubb_assign, 0)
7722 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, EXPR_BINARY_MUL_ASSIGN,
7723                       semantic_arithmetic_assign, 0)
7724 CREATE_BINEXPR_PARSER(T_SLASHEQUAL, EXPR_BINARY_DIV_ASSIGN,
7725                       semantic_arithmetic_assign, 0)
7726 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, EXPR_BINARY_MOD_ASSIGN,
7727                       semantic_arithmetic_assign, 0)
7728 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, EXPR_BINARY_SHIFTLEFT_ASSIGN,
7729                       semantic_arithmetic_assign, 0)
7730 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, EXPR_BINARY_SHIFTRIGHT_ASSIGN,
7731                       semantic_arithmetic_assign, 0)
7732 CREATE_BINEXPR_PARSER(T_ANDEQUAL, EXPR_BINARY_BITWISE_AND_ASSIGN,
7733                       semantic_arithmetic_assign, 0)
7734 CREATE_BINEXPR_PARSER(T_PIPEEQUAL, EXPR_BINARY_BITWISE_OR_ASSIGN,
7735                       semantic_arithmetic_assign, 0)
7736 CREATE_BINEXPR_PARSER(T_CARETEQUAL, EXPR_BINARY_BITWISE_XOR_ASSIGN,
7737                       semantic_arithmetic_assign, 0)
7738
7739 static expression_t *parse_sub_expression(unsigned precedence)
7740 {
7741         if (token.type < 0) {
7742                 return expected_expression_error();
7743         }
7744
7745         expression_parser_function_t *parser
7746                 = &expression_parsers[token.type];
7747         source_position_t             source_position = token.source_position;
7748         expression_t                 *left;
7749
7750         if (parser->parser != NULL) {
7751                 left = parser->parser(parser->precedence);
7752         } else {
7753                 left = parse_primary_expression();
7754         }
7755         assert(left != NULL);
7756         left->base.source_position = source_position;
7757
7758         while(true) {
7759                 if (token.type < 0) {
7760                         return expected_expression_error();
7761                 }
7762
7763                 parser = &expression_parsers[token.type];
7764                 if (parser->infix_parser == NULL)
7765                         break;
7766                 if (parser->infix_precedence < precedence)
7767                         break;
7768
7769                 left = parser->infix_parser(parser->infix_precedence, left);
7770
7771                 assert(left != NULL);
7772                 assert(left->kind != EXPR_UNKNOWN);
7773                 left->base.source_position = source_position;
7774         }
7775
7776         return left;
7777 }
7778
7779 /**
7780  * Parse an expression.
7781  */
7782 static expression_t *parse_expression(void)
7783 {
7784         return parse_sub_expression(1);
7785 }
7786
7787 /**
7788  * Register a parser for a prefix-like operator with given precedence.
7789  *
7790  * @param parser      the parser function
7791  * @param token_type  the token type of the prefix token
7792  * @param precedence  the precedence of the operator
7793  */
7794 static void register_expression_parser(parse_expression_function parser,
7795                                        int token_type, unsigned precedence)
7796 {
7797         expression_parser_function_t *entry = &expression_parsers[token_type];
7798
7799         if (entry->parser != NULL) {
7800                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
7801                 panic("trying to register multiple expression parsers for a token");
7802         }
7803         entry->parser     = parser;
7804         entry->precedence = precedence;
7805 }
7806
7807 /**
7808  * Register a parser for an infix operator with given precedence.
7809  *
7810  * @param parser      the parser function
7811  * @param token_type  the token type of the infix operator
7812  * @param precedence  the precedence of the operator
7813  */
7814 static void register_infix_parser(parse_expression_infix_function parser,
7815                 int token_type, unsigned precedence)
7816 {
7817         expression_parser_function_t *entry = &expression_parsers[token_type];
7818
7819         if (entry->infix_parser != NULL) {
7820                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
7821                 panic("trying to register multiple infix expression parsers for a "
7822                       "token");
7823         }
7824         entry->infix_parser     = parser;
7825         entry->infix_precedence = precedence;
7826 }
7827
7828 /**
7829  * Initialize the expression parsers.
7830  */
7831 static void init_expression_parsers(void)
7832 {
7833         memset(&expression_parsers, 0, sizeof(expression_parsers));
7834
7835         register_infix_parser(parse_array_expression,         '[',              30);
7836         register_infix_parser(parse_call_expression,          '(',              30);
7837         register_infix_parser(parse_select_expression,        '.',              30);
7838         register_infix_parser(parse_select_expression,        T_MINUSGREATER,   30);
7839         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,
7840                                                               T_PLUSPLUS,       30);
7841         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,
7842                                                               T_MINUSMINUS,     30);
7843
7844         register_infix_parser(parse_EXPR_BINARY_MUL,          '*',              17);
7845         register_infix_parser(parse_EXPR_BINARY_DIV,          '/',              17);
7846         register_infix_parser(parse_EXPR_BINARY_MOD,          '%',              17);
7847         register_infix_parser(parse_EXPR_BINARY_ADD,          '+',              16);
7848         register_infix_parser(parse_EXPR_BINARY_SUB,          '-',              16);
7849         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,    T_LESSLESS,       15);
7850         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,   T_GREATERGREATER, 15);
7851         register_infix_parser(parse_EXPR_BINARY_LESS,         '<',              14);
7852         register_infix_parser(parse_EXPR_BINARY_GREATER,      '>',              14);
7853         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,    T_LESSEQUAL,      14);
7854         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL, T_GREATEREQUAL,   14);
7855         register_infix_parser(parse_EXPR_BINARY_EQUAL,        T_EQUALEQUAL,     13);
7856         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,
7857                                                     T_EXCLAMATIONMARKEQUAL, 13);
7858         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,  '&',              12);
7859         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,  '^',              11);
7860         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,   '|',              10);
7861         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,  T_ANDAND,          9);
7862         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,   T_PIPEPIPE,        8);
7863         register_infix_parser(parse_conditional_expression,   '?',               7);
7864         register_infix_parser(parse_EXPR_BINARY_ASSIGN,       '=',               2);
7865         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,   T_PLUSEQUAL,       2);
7866         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,   T_MINUSEQUAL,      2);
7867         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,   T_ASTERISKEQUAL,   2);
7868         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,   T_SLASHEQUAL,      2);
7869         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,   T_PERCENTEQUAL,    2);
7870         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,
7871                                                                 T_LESSLESSEQUAL, 2);
7872         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,
7873                                                           T_GREATERGREATEREQUAL, 2);
7874         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN,
7875                                                                      T_ANDEQUAL, 2);
7876         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,
7877                                                                     T_PIPEEQUAL, 2);
7878         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN,
7879                                                                    T_CARETEQUAL, 2);
7880
7881         register_infix_parser(parse_EXPR_BINARY_COMMA,        ',',               1);
7882
7883         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-',      25);
7884         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+',      25);
7885         register_expression_parser(parse_EXPR_UNARY_NOT,              '!',      25);
7886         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~',      25);
7887         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*',      25);
7888         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&',      25);
7889         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT,
7890                                                                   T_PLUSPLUS,   25);
7891         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT,
7892                                                                   T_MINUSMINUS, 25);
7893         register_expression_parser(parse_sizeof,                      T_sizeof, 25);
7894         register_expression_parser(parse_alignof,                T___alignof__, 25);
7895         register_expression_parser(parse_extension,            T___extension__, 25);
7896         register_expression_parser(parse_builtin_classify_type,
7897                                                      T___builtin_classify_type, 25);
7898 }
7899
7900 /**
7901  * Parse a asm statement arguments specification.
7902  */
7903 static asm_argument_t *parse_asm_arguments(bool is_out)
7904 {
7905         asm_argument_t *result = NULL;
7906         asm_argument_t *last   = NULL;
7907
7908         while (token.type == T_STRING_LITERAL || token.type == '[') {
7909                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
7910                 memset(argument, 0, sizeof(argument[0]));
7911
7912                 if (token.type == '[') {
7913                         eat('[');
7914                         if (token.type != T_IDENTIFIER) {
7915                                 parse_error_expected("while parsing asm argument",
7916                                                      T_IDENTIFIER, NULL);
7917                                 return NULL;
7918                         }
7919                         argument->symbol = token.v.symbol;
7920
7921                         expect(']');
7922                 }
7923
7924                 argument->constraints = parse_string_literals();
7925                 expect('(');
7926                 add_anchor_token(')');
7927                 expression_t *expression = parse_expression();
7928                 rem_anchor_token(')');
7929                 if (is_out) {
7930                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
7931                          * change size or type representation (e.g. int -> long is ok, but
7932                          * int -> float is not) */
7933                         if (expression->kind == EXPR_UNARY_CAST) {
7934                                 type_t      *const type = expression->base.type;
7935                                 type_kind_t  const kind = type->kind;
7936                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
7937                                         unsigned flags;
7938                                         unsigned size;
7939                                         if (kind == TYPE_ATOMIC) {
7940                                                 atomic_type_kind_t const akind = type->atomic.akind;
7941                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
7942                                                 size  = get_atomic_type_size(akind);
7943                                         } else {
7944                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
7945                                                 size  = get_atomic_type_size(get_intptr_kind());
7946                                         }
7947
7948                                         do {
7949                                                 expression_t *const value      = expression->unary.value;
7950                                                 type_t       *const value_type = value->base.type;
7951                                                 type_kind_t   const value_kind = value_type->kind;
7952
7953                                                 unsigned value_flags;
7954                                                 unsigned value_size;
7955                                                 if (value_kind == TYPE_ATOMIC) {
7956                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
7957                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
7958                                                         value_size  = get_atomic_type_size(value_akind);
7959                                                 } else if (value_kind == TYPE_POINTER) {
7960                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
7961                                                         value_size  = get_atomic_type_size(get_intptr_kind());
7962                                                 } else {
7963                                                         break;
7964                                                 }
7965
7966                                                 if (value_flags != flags || value_size != size)
7967                                                         break;
7968
7969                                                 expression = value;
7970                                         } while (expression->kind == EXPR_UNARY_CAST);
7971                                 }
7972                         }
7973
7974                         if (!is_lvalue(expression)) {
7975                                 errorf(&expression->base.source_position,
7976                                        "asm output argument is not an lvalue");
7977                         }
7978                 }
7979                 argument->expression = expression;
7980                 expect(')');
7981
7982                 set_address_taken(expression, true);
7983
7984                 if (last != NULL) {
7985                         last->next = argument;
7986                 } else {
7987                         result = argument;
7988                 }
7989                 last = argument;
7990
7991                 if (token.type != ',')
7992                         break;
7993                 eat(',');
7994         }
7995
7996         return result;
7997 end_error:
7998         return NULL;
7999 }
8000
8001 /**
8002  * Parse a asm statement clobber specification.
8003  */
8004 static asm_clobber_t *parse_asm_clobbers(void)
8005 {
8006         asm_clobber_t *result = NULL;
8007         asm_clobber_t *last   = NULL;
8008
8009         while(token.type == T_STRING_LITERAL) {
8010                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
8011                 clobber->clobber       = parse_string_literals();
8012
8013                 if (last != NULL) {
8014                         last->next = clobber;
8015                 } else {
8016                         result = clobber;
8017                 }
8018                 last = clobber;
8019
8020                 if (token.type != ',')
8021                         break;
8022                 eat(',');
8023         }
8024
8025         return result;
8026 }
8027
8028 /**
8029  * Parse an asm statement.
8030  */
8031 static statement_t *parse_asm_statement(void)
8032 {
8033         eat(T_asm);
8034
8035         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
8036         statement->base.source_position = token.source_position;
8037
8038         asm_statement_t *asm_statement = &statement->asms;
8039
8040         if (token.type == T_volatile) {
8041                 next_token();
8042                 asm_statement->is_volatile = true;
8043         }
8044
8045         expect('(');
8046         add_anchor_token(')');
8047         add_anchor_token(':');
8048         asm_statement->asm_text = parse_string_literals();
8049
8050         if (token.type != ':') {
8051                 rem_anchor_token(':');
8052                 goto end_of_asm;
8053         }
8054         eat(':');
8055
8056         asm_statement->outputs = parse_asm_arguments(true);
8057         if (token.type != ':') {
8058                 rem_anchor_token(':');
8059                 goto end_of_asm;
8060         }
8061         eat(':');
8062
8063         asm_statement->inputs = parse_asm_arguments(false);
8064         if (token.type != ':') {
8065                 rem_anchor_token(':');
8066                 goto end_of_asm;
8067         }
8068         rem_anchor_token(':');
8069         eat(':');
8070
8071         asm_statement->clobbers = parse_asm_clobbers();
8072
8073 end_of_asm:
8074         rem_anchor_token(')');
8075         expect(')');
8076         expect(';');
8077
8078         if (asm_statement->outputs == NULL) {
8079                 /* GCC: An 'asm' instruction without any output operands will be treated
8080                  * identically to a volatile 'asm' instruction. */
8081                 asm_statement->is_volatile = true;
8082         }
8083
8084         return statement;
8085 end_error:
8086         return create_invalid_statement();
8087 }
8088
8089 /**
8090  * Parse a case statement.
8091  */
8092 static statement_t *parse_case_statement(void)
8093 {
8094         eat(T_case);
8095
8096         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8097         source_position_t *const pos       = &statement->base.source_position;
8098
8099         *pos                             = token.source_position;
8100         statement->case_label.expression = parse_expression();
8101
8102         PUSH_PARENT(statement);
8103
8104         if (c_mode & _GNUC) {
8105                 if (token.type == T_DOTDOTDOT) {
8106                         next_token();
8107                         statement->case_label.end_range = parse_expression();
8108                 }
8109         }
8110
8111         expect(':');
8112
8113         if (! is_constant_expression(statement->case_label.expression)) {
8114                 errorf(pos, "case label does not reduce to an integer constant");
8115         } else if (current_switch != NULL) {
8116                 /* Check for duplicate case values */
8117                 /* FIXME slow */
8118                 long const val = fold_constant(statement->case_label.expression);
8119                 for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
8120                         expression_t const* const e = l->expression;
8121                         if (e == NULL || !is_constant_expression(e) || fold_constant(e) != val)
8122                                 continue;
8123
8124                         errorf(pos, "duplicate case value");
8125                         errorf(&l->base.source_position, "previously used here");
8126                         break;
8127                 }
8128
8129                 /* link all cases into the switch statement */
8130                 if (current_switch->last_case == NULL) {
8131                         current_switch->first_case      = &statement->case_label;
8132                 } else {
8133                         current_switch->last_case->next = &statement->case_label;
8134                 }
8135                 current_switch->last_case = &statement->case_label;
8136         } else {
8137                 errorf(pos, "case label not within a switch statement");
8138         }
8139
8140         statement_t *const inner_stmt = parse_statement();
8141         statement->case_label.statement = inner_stmt;
8142         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8143                 errorf(&inner_stmt->base.source_position, "declaration after case label");
8144         }
8145
8146         POP_PARENT;
8147         return statement;
8148 end_error:
8149         POP_PARENT;
8150         return create_invalid_statement();
8151 }
8152
8153 /**
8154  * Finds an existing default label of a switch statement.
8155  */
8156 static case_label_statement_t *
8157 find_default_label(const switch_statement_t *statement)
8158 {
8159         case_label_statement_t *label = statement->first_case;
8160         for ( ; label != NULL; label = label->next) {
8161                 if (label->expression == NULL)
8162                         return label;
8163         }
8164         return NULL;
8165 }
8166
8167 /**
8168  * Parse a default statement.
8169  */
8170 static statement_t *parse_default_statement(void)
8171 {
8172         eat(T_default);
8173
8174         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8175         statement->base.source_position = token.source_position;
8176
8177         PUSH_PARENT(statement);
8178
8179         expect(':');
8180         if (current_switch != NULL) {
8181                 const case_label_statement_t *def_label = find_default_label(current_switch);
8182                 if (def_label != NULL) {
8183                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
8184                                &def_label->base.source_position);
8185                 } else {
8186                         /* link all cases into the switch statement */
8187                         if (current_switch->last_case == NULL) {
8188                                 current_switch->first_case      = &statement->case_label;
8189                         } else {
8190                                 current_switch->last_case->next = &statement->case_label;
8191                         }
8192                         current_switch->last_case = &statement->case_label;
8193                 }
8194         } else {
8195                 errorf(&statement->base.source_position,
8196                         "'default' label not within a switch statement");
8197         }
8198
8199         statement_t *const inner_stmt = parse_statement();
8200         statement->case_label.statement = inner_stmt;
8201         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8202                 errorf(&inner_stmt->base.source_position, "declaration after default label");
8203         }
8204
8205         POP_PARENT;
8206         return statement;
8207 end_error:
8208         POP_PARENT;
8209         return create_invalid_statement();
8210 }
8211
8212 /**
8213  * Return the declaration for a given label symbol or create a new one.
8214  *
8215  * @param symbol  the symbol of the label
8216  */
8217 static declaration_t *get_label(symbol_t *symbol)
8218 {
8219         declaration_t *candidate = get_declaration(symbol, NAMESPACE_LABEL);
8220         assert(current_function != NULL);
8221         /* if we found a label in the same function, then we already created the
8222          * declaration */
8223         if (candidate != NULL
8224                         && candidate->parent_scope == &current_function->scope) {
8225                 return candidate;
8226         }
8227
8228         /* otherwise we need to create a new one */
8229         declaration_t *const declaration = allocate_declaration_zero();
8230         declaration->namespc       = NAMESPACE_LABEL;
8231         declaration->symbol        = symbol;
8232
8233         label_push(declaration);
8234
8235         return declaration;
8236 }
8237
8238 /**
8239  * Parse a label statement.
8240  */
8241 static statement_t *parse_label_statement(void)
8242 {
8243         assert(token.type == T_IDENTIFIER);
8244         symbol_t *symbol = token.v.symbol;
8245         next_token();
8246
8247         declaration_t *label = get_label(symbol);
8248
8249         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
8250         statement->base.source_position = token.source_position;
8251         statement->label.label          = label;
8252
8253         PUSH_PARENT(statement);
8254
8255         /* if source position is already set then the label is defined twice,
8256          * otherwise it was just mentioned in a goto so far */
8257         if (label->source_position.input_name != NULL) {
8258                 errorf(HERE, "duplicate label '%Y' (declared %P)",
8259                        symbol, &label->source_position);
8260         } else {
8261                 label->source_position = token.source_position;
8262                 label->init.statement  = statement;
8263         }
8264
8265         eat(':');
8266
8267         if (token.type == '}') {
8268                 /* TODO only warn? */
8269                 if (false) {
8270                         warningf(HERE, "label at end of compound statement");
8271                         statement->label.statement = create_empty_statement();
8272                 } else {
8273                         errorf(HERE, "label at end of compound statement");
8274                         statement->label.statement = create_invalid_statement();
8275                 }
8276         } else if (token.type == ';') {
8277                 /* Eat an empty statement here, to avoid the warning about an empty
8278                  * statement after a label.  label:; is commonly used to have a label
8279                  * before a closing brace. */
8280                 statement->label.statement = create_empty_statement();
8281                 next_token();
8282         } else {
8283                 statement_t *const inner_stmt = parse_statement();
8284                 statement->label.statement = inner_stmt;
8285                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
8286                         errorf(&inner_stmt->base.source_position, "declaration after label");
8287                 }
8288         }
8289
8290         /* remember the labels in a list for later checking */
8291         if (label_last == NULL) {
8292                 label_first = &statement->label;
8293         } else {
8294                 label_last->next = &statement->label;
8295         }
8296         label_last = &statement->label;
8297
8298         POP_PARENT;
8299         return statement;
8300 }
8301
8302 /**
8303  * Parse an if statement.
8304  */
8305 static statement_t *parse_if(void)
8306 {
8307         eat(T_if);
8308
8309         statement_t *statement          = allocate_statement_zero(STATEMENT_IF);
8310         statement->base.source_position = token.source_position;
8311
8312         PUSH_PARENT(statement);
8313
8314         expect('(');
8315         add_anchor_token(')');
8316         statement->ifs.condition = parse_expression();
8317         rem_anchor_token(')');
8318         expect(')');
8319
8320         add_anchor_token(T_else);
8321         statement->ifs.true_statement = parse_statement();
8322         rem_anchor_token(T_else);
8323
8324         if (token.type == T_else) {
8325                 next_token();
8326                 statement->ifs.false_statement = parse_statement();
8327         }
8328
8329         POP_PARENT;
8330         return statement;
8331 end_error:
8332         POP_PARENT;
8333         return create_invalid_statement();
8334 }
8335
8336 /**
8337  * Parse a switch statement.
8338  */
8339 static statement_t *parse_switch(void)
8340 {
8341         eat(T_switch);
8342
8343         statement_t *statement          = allocate_statement_zero(STATEMENT_SWITCH);
8344         statement->base.source_position = token.source_position;
8345
8346         PUSH_PARENT(statement);
8347
8348         expect('(');
8349         expression_t *const expr = parse_expression();
8350         type_t       *      type = skip_typeref(expr->base.type);
8351         if (is_type_integer(type)) {
8352                 type = promote_integer(type);
8353         } else if (is_type_valid(type)) {
8354                 errorf(&expr->base.source_position,
8355                        "switch quantity is not an integer, but '%T'", type);
8356                 type = type_error_type;
8357         }
8358         statement->switchs.expression = create_implicit_cast(expr, type);
8359         expect(')');
8360
8361         switch_statement_t *rem = current_switch;
8362         current_switch          = &statement->switchs;
8363         statement->switchs.body = parse_statement();
8364         current_switch          = rem;
8365
8366         if (warning.switch_default &&
8367            find_default_label(&statement->switchs) == NULL) {
8368                 warningf(&statement->base.source_position, "switch has no default case");
8369         }
8370
8371         POP_PARENT;
8372         return statement;
8373 end_error:
8374         POP_PARENT;
8375         return create_invalid_statement();
8376 }
8377
8378 static statement_t *parse_loop_body(statement_t *const loop)
8379 {
8380         statement_t *const rem = current_loop;
8381         current_loop = loop;
8382
8383         statement_t *const body = parse_statement();
8384
8385         current_loop = rem;
8386         return body;
8387 }
8388
8389 /**
8390  * Parse a while statement.
8391  */
8392 static statement_t *parse_while(void)
8393 {
8394         eat(T_while);
8395
8396         statement_t *statement          = allocate_statement_zero(STATEMENT_WHILE);
8397         statement->base.source_position = token.source_position;
8398
8399         PUSH_PARENT(statement);
8400
8401         expect('(');
8402         add_anchor_token(')');
8403         statement->whiles.condition = parse_expression();
8404         rem_anchor_token(')');
8405         expect(')');
8406
8407         statement->whiles.body = parse_loop_body(statement);
8408
8409         POP_PARENT;
8410         return statement;
8411 end_error:
8412         POP_PARENT;
8413         return create_invalid_statement();
8414 }
8415
8416 /**
8417  * Parse a do statement.
8418  */
8419 static statement_t *parse_do(void)
8420 {
8421         eat(T_do);
8422
8423         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
8424         statement->base.source_position = token.source_position;
8425
8426         PUSH_PARENT(statement)
8427
8428         add_anchor_token(T_while);
8429         statement->do_while.body = parse_loop_body(statement);
8430         rem_anchor_token(T_while);
8431
8432         expect(T_while);
8433         expect('(');
8434         add_anchor_token(')');
8435         statement->do_while.condition = parse_expression();
8436         rem_anchor_token(')');
8437         expect(')');
8438         expect(';');
8439
8440         POP_PARENT;
8441         return statement;
8442 end_error:
8443         POP_PARENT;
8444         return create_invalid_statement();
8445 }
8446
8447 /**
8448  * Parse a for statement.
8449  */
8450 static statement_t *parse_for(void)
8451 {
8452         eat(T_for);
8453
8454         statement_t *statement          = allocate_statement_zero(STATEMENT_FOR);
8455         statement->base.source_position = token.source_position;
8456
8457         PUSH_PARENT(statement);
8458
8459         int      top        = environment_top();
8460         scope_t *last_scope = scope;
8461         set_scope(&statement->fors.scope);
8462
8463         expect('(');
8464         add_anchor_token(')');
8465
8466         if (token.type != ';') {
8467                 if (is_declaration_specifier(&token, false)) {
8468                         parse_declaration(record_declaration);
8469                 } else {
8470                         add_anchor_token(';');
8471                         expression_t *const init = parse_expression();
8472                         statement->fors.initialisation = init;
8473                         if (warning.unused_value && !expression_has_effect(init)) {
8474                                 warningf(&init->base.source_position,
8475                                          "initialisation of 'for'-statement has no effect");
8476                         }
8477                         rem_anchor_token(';');
8478                         expect(';');
8479                 }
8480         } else {
8481                 expect(';');
8482         }
8483
8484         if (token.type != ';') {
8485                 add_anchor_token(';');
8486                 statement->fors.condition = parse_expression();
8487                 rem_anchor_token(';');
8488         }
8489         expect(';');
8490         if (token.type != ')') {
8491                 expression_t *const step = parse_expression();
8492                 statement->fors.step = step;
8493                 if (warning.unused_value && !expression_has_effect(step)) {
8494                         warningf(&step->base.source_position,
8495                                  "step of 'for'-statement has no effect");
8496                 }
8497         }
8498         rem_anchor_token(')');
8499         expect(')');
8500         statement->fors.body = parse_loop_body(statement);
8501
8502         assert(scope == &statement->fors.scope);
8503         set_scope(last_scope);
8504         environment_pop_to(top);
8505
8506         POP_PARENT;
8507         return statement;
8508
8509 end_error:
8510         POP_PARENT;
8511         rem_anchor_token(')');
8512         assert(scope == &statement->fors.scope);
8513         set_scope(last_scope);
8514         environment_pop_to(top);
8515
8516         return create_invalid_statement();
8517 }
8518
8519 /**
8520  * Parse a goto statement.
8521  */
8522 static statement_t *parse_goto(void)
8523 {
8524         eat(T_goto);
8525
8526         if (token.type != T_IDENTIFIER) {
8527                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
8528                 eat_statement();
8529                 goto end_error;
8530         }
8531         symbol_t *symbol = token.v.symbol;
8532         next_token();
8533
8534         declaration_t *label = get_label(symbol);
8535
8536         statement_t *statement          = allocate_statement_zero(STATEMENT_GOTO);
8537         statement->base.source_position = token.source_position;
8538
8539         statement->gotos.label = label;
8540
8541         /* remember the goto's in a list for later checking */
8542         if (goto_last == NULL) {
8543                 goto_first = &statement->gotos;
8544         } else {
8545                 goto_last->next = &statement->gotos;
8546         }
8547         goto_last = &statement->gotos;
8548
8549         expect(';');
8550
8551         return statement;
8552 end_error:
8553         return create_invalid_statement();
8554 }
8555
8556 /**
8557  * Parse a continue statement.
8558  */
8559 static statement_t *parse_continue(void)
8560 {
8561         statement_t *statement;
8562         if (current_loop == NULL) {
8563                 errorf(HERE, "continue statement not within loop");
8564                 statement = create_invalid_statement();
8565         } else {
8566                 statement = allocate_statement_zero(STATEMENT_CONTINUE);
8567
8568                 statement->base.source_position = token.source_position;
8569         }
8570
8571         eat(T_continue);
8572         expect(';');
8573
8574         return statement;
8575 end_error:
8576         return create_invalid_statement();
8577 }
8578
8579 /**
8580  * Parse a break statement.
8581  */
8582 static statement_t *parse_break(void)
8583 {
8584         statement_t *statement;
8585         if (current_switch == NULL && current_loop == NULL) {
8586                 errorf(HERE, "break statement not within loop or switch");
8587                 statement = create_invalid_statement();
8588         } else {
8589                 statement = allocate_statement_zero(STATEMENT_BREAK);
8590
8591                 statement->base.source_position = token.source_position;
8592         }
8593
8594         eat(T_break);
8595         expect(';');
8596
8597         return statement;
8598 end_error:
8599         return create_invalid_statement();
8600 }
8601
8602 /**
8603  * Parse a __leave statement.
8604  */
8605 static statement_t *parse_leave(void)
8606 {
8607         statement_t *statement;
8608         if (current_try == NULL) {
8609                 errorf(HERE, "__leave statement not within __try");
8610                 statement = create_invalid_statement();
8611         } else {
8612                 statement = allocate_statement_zero(STATEMENT_LEAVE);
8613
8614                 statement->base.source_position = token.source_position;
8615         }
8616
8617         eat(T___leave);
8618         expect(';');
8619
8620         return statement;
8621 end_error:
8622         return create_invalid_statement();
8623 }
8624
8625 /**
8626  * Check if a given declaration represents a local variable.
8627  */
8628 static bool is_local_var_declaration(const declaration_t *declaration)
8629 {
8630         switch ((storage_class_tag_t) declaration->storage_class) {
8631         case STORAGE_CLASS_AUTO:
8632         case STORAGE_CLASS_REGISTER: {
8633                 const type_t *type = skip_typeref(declaration->type);
8634                 if (is_type_function(type)) {
8635                         return false;
8636                 } else {
8637                         return true;
8638                 }
8639         }
8640         default:
8641                 return false;
8642         }
8643 }
8644
8645 /**
8646  * Check if a given declaration represents a variable.
8647  */
8648 static bool is_var_declaration(const declaration_t *declaration)
8649 {
8650         if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
8651                 return false;
8652
8653         const type_t *type = skip_typeref(declaration->type);
8654         return !is_type_function(type);
8655 }
8656
8657 /**
8658  * Check if a given expression represents a local variable.
8659  */
8660 static bool is_local_variable(const expression_t *expression)
8661 {
8662         if (expression->base.kind != EXPR_REFERENCE) {
8663                 return false;
8664         }
8665         const declaration_t *declaration = expression->reference.declaration;
8666         return is_local_var_declaration(declaration);
8667 }
8668
8669 /**
8670  * Check if a given expression represents a local variable and
8671  * return its declaration then, else return NULL.
8672  */
8673 declaration_t *expr_is_variable(const expression_t *expression)
8674 {
8675         if (expression->base.kind != EXPR_REFERENCE) {
8676                 return NULL;
8677         }
8678         declaration_t *declaration = expression->reference.declaration;
8679         if (is_var_declaration(declaration))
8680                 return declaration;
8681         return NULL;
8682 }
8683
8684 /**
8685  * Parse a return statement.
8686  */
8687 static statement_t *parse_return(void)
8688 {
8689         statement_t *statement          = allocate_statement_zero(STATEMENT_RETURN);
8690         statement->base.source_position = token.source_position;
8691
8692         eat(T_return);
8693
8694         expression_t *return_value = NULL;
8695         if (token.type != ';') {
8696                 return_value = parse_expression();
8697         }
8698         expect(';');
8699
8700         const type_t *const func_type = current_function->type;
8701         assert(is_type_function(func_type));
8702         type_t *const return_type = skip_typeref(func_type->function.return_type);
8703
8704         if (return_value != NULL) {
8705                 type_t *return_value_type = skip_typeref(return_value->base.type);
8706
8707                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)
8708                                 && !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
8709                         warningf(&statement->base.source_position,
8710                                  "'return' with a value, in function returning void");
8711                         return_value = NULL;
8712                 } else {
8713                         assign_error_t error = semantic_assign(return_type, return_value);
8714                         report_assign_error(error, return_type, return_value, "'return'",
8715                                             &statement->base.source_position);
8716                         return_value = create_implicit_cast(return_value, return_type);
8717                 }
8718                 /* check for returning address of a local var */
8719                 if (return_value != NULL &&
8720                                 return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
8721                         const expression_t *expression = return_value->unary.value;
8722                         if (is_local_variable(expression)) {
8723                                 warningf(&statement->base.source_position,
8724                                          "function returns address of local variable");
8725                         }
8726                 }
8727         } else {
8728                 if (!is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
8729                         warningf(&statement->base.source_position,
8730                                  "'return' without value, in function returning non-void");
8731                 }
8732         }
8733         statement->returns.value = return_value;
8734
8735         return statement;
8736 end_error:
8737         return create_invalid_statement();
8738 }
8739
8740 /**
8741  * Parse a declaration statement.
8742  */
8743 static statement_t *parse_declaration_statement(void)
8744 {
8745         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
8746
8747         statement->base.source_position = token.source_position;
8748
8749         declaration_t *before = last_declaration;
8750         parse_declaration(record_declaration);
8751
8752         if (before == NULL) {
8753                 statement->declaration.declarations_begin = scope->declarations;
8754         } else {
8755                 statement->declaration.declarations_begin = before->next;
8756         }
8757         statement->declaration.declarations_end = last_declaration;
8758
8759         return statement;
8760 }
8761
8762 /**
8763  * Parse an expression statement, ie. expr ';'.
8764  */
8765 static statement_t *parse_expression_statement(void)
8766 {
8767         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
8768
8769         statement->base.source_position  = token.source_position;
8770         expression_t *const expr         = parse_expression();
8771         statement->expression.expression = expr;
8772
8773         expect(';');
8774
8775         return statement;
8776 end_error:
8777         return create_invalid_statement();
8778 }
8779
8780 /**
8781  * Parse a microsoft __try { } __finally { } or
8782  * __try{ } __except() { }
8783  */
8784 static statement_t *parse_ms_try_statment(void)
8785 {
8786         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
8787
8788         statement->base.source_position  = token.source_position;
8789         eat(T___try);
8790
8791         ms_try_statement_t *rem = current_try;
8792         current_try = &statement->ms_try;
8793         statement->ms_try.try_statement = parse_compound_statement(false);
8794         current_try = rem;
8795
8796         if (token.type == T___except) {
8797                 eat(T___except);
8798                 expect('(');
8799                 add_anchor_token(')');
8800                 expression_t *const expr = parse_expression();
8801                 type_t       *      type = skip_typeref(expr->base.type);
8802                 if (is_type_integer(type)) {
8803                         type = promote_integer(type);
8804                 } else if (is_type_valid(type)) {
8805                         errorf(&expr->base.source_position,
8806                                "__expect expression is not an integer, but '%T'", type);
8807                         type = type_error_type;
8808                 }
8809                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
8810                 rem_anchor_token(')');
8811                 expect(')');
8812                 statement->ms_try.final_statement = parse_compound_statement(false);
8813         } else if (token.type == T__finally) {
8814                 eat(T___finally);
8815                 statement->ms_try.final_statement = parse_compound_statement(false);
8816         } else {
8817                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
8818                 return create_invalid_statement();
8819         }
8820         return statement;
8821 end_error:
8822         return create_invalid_statement();
8823 }
8824
8825 static statement_t *parse_empty_statement(void)
8826 {
8827         if (warning.empty_statement) {
8828                 warningf(HERE, "statement is empty");
8829         }
8830         eat(';');
8831         return create_empty_statement();
8832 }
8833
8834 /**
8835  * Parse a statement.
8836  * There's also parse_statement() which additionally checks for
8837  * "statement has no effect" warnings
8838  */
8839 static statement_t *intern_parse_statement(void)
8840 {
8841         statement_t *statement = NULL;
8842
8843         /* declaration or statement */
8844         add_anchor_token(';');
8845         switch (token.type) {
8846         case T_IDENTIFIER:
8847                 if (look_ahead(1)->type == ':') {
8848                         statement = parse_label_statement();
8849                 } else if (is_typedef_symbol(token.v.symbol)) {
8850                         statement = parse_declaration_statement();
8851                 } else {
8852                         statement = parse_expression_statement();
8853                 }
8854                 break;
8855
8856         case T___extension__:
8857                 /* This can be a prefix to a declaration or an expression statement.
8858                  * We simply eat it now and parse the rest with tail recursion. */
8859                 do {
8860                         next_token();
8861                 } while (token.type == T___extension__);
8862                 statement = parse_statement();
8863                 break;
8864
8865         DECLARATION_START
8866                 statement = parse_declaration_statement();
8867                 break;
8868
8869         case ';':        statement = parse_empty_statement();         break;
8870         case '{':        statement = parse_compound_statement(false); break;
8871         case T___leave:  statement = parse_leave();                   break;
8872         case T___try:    statement = parse_ms_try_statment();         break;
8873         case T_asm:      statement = parse_asm_statement();           break;
8874         case T_break:    statement = parse_break();                   break;
8875         case T_case:     statement = parse_case_statement();          break;
8876         case T_continue: statement = parse_continue();                break;
8877         case T_default:  statement = parse_default_statement();       break;
8878         case T_do:       statement = parse_do();                      break;
8879         case T_for:      statement = parse_for();                     break;
8880         case T_goto:     statement = parse_goto();                    break;
8881         case T_if:       statement = parse_if ();                     break;
8882         case T_return:   statement = parse_return();                  break;
8883         case T_switch:   statement = parse_switch();                  break;
8884         case T_while:    statement = parse_while();                   break;
8885         default:         statement = parse_expression_statement();    break;
8886         }
8887         rem_anchor_token(';');
8888
8889         assert(statement != NULL
8890                         && statement->base.source_position.input_name != NULL);
8891
8892         return statement;
8893 }
8894
8895 /**
8896  * parse a statement and emits "statement has no effect" warning if needed
8897  * (This is really a wrapper around intern_parse_statement with check for 1
8898  *  single warning. It is needed, because for statement expressions we have
8899  *  to avoid the warning on the last statement)
8900  */
8901 static statement_t *parse_statement(void)
8902 {
8903         statement_t *statement = intern_parse_statement();
8904
8905         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
8906                 expression_t *expression = statement->expression.expression;
8907                 if (!expression_has_effect(expression)) {
8908                         warningf(&expression->base.source_position,
8909                                         "statement has no effect");
8910                 }
8911         }
8912
8913         return statement;
8914 }
8915
8916 /**
8917  * Parse a compound statement.
8918  */
8919 static statement_t *parse_compound_statement(bool inside_expression_statement)
8920 {
8921         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
8922         statement->base.source_position = token.source_position;
8923
8924         PUSH_PARENT(statement);
8925
8926         eat('{');
8927         add_anchor_token('}');
8928
8929         int      top        = environment_top();
8930         scope_t *last_scope = scope;
8931         set_scope(&statement->compound.scope);
8932
8933         statement_t *last_statement = NULL;
8934
8935         bool only_decls_so_far = true;
8936         while (token.type != '}' && token.type != T_EOF) {
8937                 statement_t *sub_statement = intern_parse_statement();
8938                 if (is_invalid_statement(sub_statement)) {
8939                         /* an error occurred. if we are at an anchor, return */
8940                         if (at_anchor())
8941                                 goto end_error;
8942                         continue;
8943                 }
8944
8945                 if (warning.declaration_after_statement) {
8946                         if (sub_statement->kind != STATEMENT_DECLARATION) {
8947                                 only_decls_so_far = false;
8948                         } else if (!only_decls_so_far) {
8949                                 warningf(&sub_statement->base.source_position,
8950                                          "ISO C90 forbids mixed declarations and code");
8951                         }
8952                 }
8953
8954                 if (last_statement != NULL) {
8955                         last_statement->base.next = sub_statement;
8956                 } else {
8957                         statement->compound.statements = sub_statement;
8958                 }
8959
8960                 while (sub_statement->base.next != NULL)
8961                         sub_statement = sub_statement->base.next;
8962
8963                 last_statement = sub_statement;
8964         }
8965
8966         if (token.type == '}') {
8967                 next_token();
8968         } else {
8969                 errorf(&statement->base.source_position,
8970                        "end of file while looking for closing '}'");
8971         }
8972
8973         /* look over all statements again to produce no effect warnings */
8974         if (warning.unused_value) {
8975                 statement_t *sub_statement = statement->compound.statements;
8976                 for( ; sub_statement != NULL; sub_statement = sub_statement->base.next) {
8977                         if (sub_statement->kind != STATEMENT_EXPRESSION)
8978                                 continue;
8979                         /* don't emit a warning for the last expression in an expression
8980                          * statement as it has always an effect */
8981                         if (inside_expression_statement && sub_statement->base.next == NULL)
8982                                 continue;
8983
8984                         expression_t *expression = sub_statement->expression.expression;
8985                         if (!expression_has_effect(expression)) {
8986                                 warningf(&expression->base.source_position,
8987                                          "statement has no effect");
8988                         }
8989                 }
8990         }
8991
8992 end_error:
8993         rem_anchor_token('}');
8994         assert(scope == &statement->compound.scope);
8995         set_scope(last_scope);
8996         environment_pop_to(top);
8997
8998         POP_PARENT;
8999         return statement;
9000 }
9001
9002 /**
9003  * Initialize builtin types.
9004  */
9005 static void initialize_builtin_types(void)
9006 {
9007         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
9008         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
9009         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
9010         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
9011         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
9012         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
9013         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    type_int);
9014         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
9015
9016         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
9017         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
9018         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
9019         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
9020 }
9021
9022 /**
9023  * Check for unused global static functions and variables
9024  */
9025 static void check_unused_globals(void)
9026 {
9027         if (!warning.unused_function && !warning.unused_variable)
9028                 return;
9029
9030         for (const declaration_t *decl = global_scope->declarations; decl != NULL; decl = decl->next) {
9031                 if (decl->used                  ||
9032                     decl->modifiers & DM_UNUSED ||
9033                     decl->modifiers & DM_USED   ||
9034                     decl->storage_class != STORAGE_CLASS_STATIC)
9035                         continue;
9036
9037                 type_t *const type = decl->type;
9038                 const char *s;
9039                 if (is_type_function(skip_typeref(type))) {
9040                         if (!warning.unused_function || decl->is_inline)
9041                                 continue;
9042
9043                         s = (decl->init.statement != NULL ? "defined" : "declared");
9044                 } else {
9045                         if (!warning.unused_variable)
9046                                 continue;
9047
9048                         s = "defined";
9049                 }
9050
9051                 warningf(&decl->source_position, "'%#T' %s but not used",
9052                         type, decl->symbol, s);
9053         }
9054 }
9055
9056 static void parse_global_asm(void)
9057 {
9058         eat(T_asm);
9059         expect('(');
9060
9061         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
9062         statement->base.source_position = token.source_position;
9063         statement->asms.asm_text        = parse_string_literals();
9064         statement->base.next            = unit->global_asm;
9065         unit->global_asm                = statement;
9066
9067         expect(')');
9068         expect(';');
9069
9070 end_error:;
9071 }
9072
9073 /**
9074  * Parse a translation unit.
9075  */
9076 static void parse_translation_unit(void)
9077 {
9078         for (;;) switch (token.type) {
9079                 DECLARATION_START
9080                 case T_IDENTIFIER:
9081                 case T___extension__:
9082                         parse_external_declaration();
9083                         break;
9084
9085                 case T_asm:
9086                         parse_global_asm();
9087                         break;
9088
9089                 case T_EOF:
9090                         return;
9091
9092                 case ';':
9093                         /* TODO error in strict mode */
9094                         warningf(HERE, "stray ';' outside of function");
9095                         next_token();
9096                         break;
9097
9098                 default:
9099                         errorf(HERE, "stray %K outside of function", &token);
9100                         if (token.type == '(' || token.type == '{' || token.type == '[')
9101                                 eat_until_matching_token(token.type);
9102                         next_token();
9103                         break;
9104         }
9105 }
9106
9107 /**
9108  * Parse the input.
9109  *
9110  * @return  the translation unit or NULL if errors occurred.
9111  */
9112 void start_parsing(void)
9113 {
9114         environment_stack = NEW_ARR_F(stack_entry_t, 0);
9115         label_stack       = NEW_ARR_F(stack_entry_t, 0);
9116         diagnostic_count  = 0;
9117         error_count       = 0;
9118         warning_count     = 0;
9119
9120         type_set_output(stderr);
9121         ast_set_output(stderr);
9122
9123         assert(unit == NULL);
9124         unit = allocate_ast_zero(sizeof(unit[0]));
9125
9126         assert(global_scope == NULL);
9127         global_scope = &unit->scope;
9128
9129         assert(scope == NULL);
9130         set_scope(&unit->scope);
9131
9132         initialize_builtin_types();
9133 }
9134
9135 translation_unit_t *finish_parsing(void)
9136 {
9137         assert(scope == &unit->scope);
9138         scope          = NULL;
9139         last_declaration = NULL;
9140
9141         assert(global_scope == &unit->scope);
9142         check_unused_globals();
9143         global_scope = NULL;
9144
9145         DEL_ARR_F(environment_stack);
9146         DEL_ARR_F(label_stack);
9147
9148         translation_unit_t *result = unit;
9149         unit = NULL;
9150         return result;
9151 }
9152
9153 void parse(void)
9154 {
9155         lookahead_bufpos = 0;
9156         for(int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
9157                 next_token();
9158         }
9159         parse_translation_unit();
9160 }
9161
9162 /**
9163  * Initialize the parser.
9164  */
9165 void init_parser(void)
9166 {
9167         if (c_mode & _MS) {
9168                 /* add predefined symbols for extended-decl-modifier */
9169                 sym_align      = symbol_table_insert("align");
9170                 sym_allocate   = symbol_table_insert("allocate");
9171                 sym_dllimport  = symbol_table_insert("dllimport");
9172                 sym_dllexport  = symbol_table_insert("dllexport");
9173                 sym_naked      = symbol_table_insert("naked");
9174                 sym_noinline   = symbol_table_insert("noinline");
9175                 sym_noreturn   = symbol_table_insert("noreturn");
9176                 sym_nothrow    = symbol_table_insert("nothrow");
9177                 sym_novtable   = symbol_table_insert("novtable");
9178                 sym_property   = symbol_table_insert("property");
9179                 sym_get        = symbol_table_insert("get");
9180                 sym_put        = symbol_table_insert("put");
9181                 sym_selectany  = symbol_table_insert("selectany");
9182                 sym_thread     = symbol_table_insert("thread");
9183                 sym_uuid       = symbol_table_insert("uuid");
9184                 sym_deprecated = symbol_table_insert("deprecated");
9185                 sym_restrict   = symbol_table_insert("restrict");
9186                 sym_noalias    = symbol_table_insert("noalias");
9187         }
9188         memset(token_anchor_set, 0, sizeof(token_anchor_set));
9189
9190         init_expression_parsers();
9191         obstack_init(&temp_obst);
9192
9193         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
9194         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
9195 }
9196
9197 /**
9198  * Terminate the parser.
9199  */
9200 void exit_parser(void)
9201 {
9202         obstack_free(&temp_obst, NULL);
9203 }