nsz Git - cparser/blob - parser.c

   1 /*
   2  * This file is part of cparser.
   3  * Copyright (C) 2007-2008 Matthias Braun <matze@braunis.de>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  18  * 02111-1307, USA.
  19  */
  20 #include <config.h>
  21
  22 #include <assert.h>
  23 #include <stdarg.h>
  24 #include <stdbool.h>
  25
  26 #include "parser.h"
  27 #include "diagnostic.h"
  28 #include "format_check.h"
  29 #include "lexer.h"
  30 #include "symbol_t.h"
  31 #include "token_t.h"
  32 #include "types.h"
  33 #include "type_t.h"
  34 #include "type_hash.h"
  35 #include "ast_t.h"
  36 #include "lang_features.h"
  37 #include "warning.h"
  38 #include "adt/bitfiddle.h"
  39 #include "adt/error.h"
  40 #include "adt/array.h"
  41
  42 //#define PRINT_TOKENS
  43 #define MAX_LOOKAHEAD 2
  44
  45 typedef struct {
  46         declaration_t *old_declaration;
  47         symbol_t      *symbol;
  48         unsigned short namespc;
  49 } stack_entry_t;
  50
  51 typedef struct argument_list_t argument_list_t;
  52 struct argument_list_t {
  53         long              argument;
  54         argument_list_t  *next;
  55 };
  56
  57 typedef struct gnu_attribute_t gnu_attribute_t;
  58 struct gnu_attribute_t {
  59         gnu_attribute_kind_t kind;           /**< The kind of the GNU attribute. */
  60         gnu_attribute_t     *next;
  61         bool                 invalid;        /**< Set if this attribute had argument errors, */
  62         bool                 have_arguments; /**< True, if this attribute has arguments. */
  63         union {
  64                 size_t              value;
  65                 string_t            string;
  66                 atomic_type_kind_t  akind;
  67                 long                argument;  /**< Single argument. */
  68                 argument_list_t    *arguments; /**< List of argument expressions. */
  69         } u;
  70 };
  71
  72 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  73 struct declaration_specifiers_t {
  74         source_position_t  source_position;
  75         unsigned char      declared_storage_class;
  76         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  77         unsigned int       is_inline : 1;
  78         unsigned int       deprecated : 1;
  79         decl_modifiers_t   modifiers;         /**< declaration modifiers */
  80         gnu_attribute_t   *gnu_attributes;    /**< list of GNU attributes */
  81         const char        *deprecated_string; /**< can be set if declaration was marked deprecated. */
  82         symbol_t          *get_property_sym;  /**< the name of the get property if set. */
  83         symbol_t          *put_property_sym;  /**< the name of the put property if set. */
  84         type_t            *type;
  85 };
  86
  87 /**
  88  * An environment for parsing initializers (and compound literals).
  89  */
  90 typedef struct parse_initializer_env_t {
  91         type_t        *type;        /**< the type of the initializer. In case of an
  92                                          array type with unspecified size this gets
  93                                          adjusted to the actual size. */
  94         declaration_t *declaration; /**< the declaration that is initialized if any */
  95         bool           must_be_constant;
  96 } parse_initializer_env_t;
  97
  98 typedef declaration_t* (*parsed_declaration_func) (declaration_t *declaration);
  99
 100 static token_t             token;
 101 static token_t             lookahead_buffer[MAX_LOOKAHEAD];
 102 static int                 lookahead_bufpos;
 103 static stack_entry_t      *environment_stack = NULL;
 104 static stack_entry_t      *label_stack       = NULL;
 105 static scope_t            *global_scope      = NULL;
 106 static scope_t            *scope             = NULL;
 107 static declaration_t      *last_declaration  = NULL;
 108 static declaration_t      *current_function  = NULL;
 109 static switch_statement_t *current_switch    = NULL;
 110 static statement_t        *current_loop      = NULL;
 111 static statement_t        *current_parent    = NULL;
 112 static ms_try_statement_t *current_try       = NULL;
 113 static goto_statement_t   *goto_first        = NULL;
 114 static goto_statement_t   *goto_last         = NULL;
 115 static label_statement_t  *label_first       = NULL;
 116 static label_statement_t  *label_last        = NULL;
 117 static translation_unit_t *unit              = NULL;
 118 static struct obstack      temp_obst;
 119
 120 #define PUSH_PARENT(stmt)                          \
 121         statement_t *const prev_parent = current_parent; \
 122         current_parent = (stmt);
 123 #define POP_PARENT ((void)(current_parent = prev_parent))
 124
 125 static source_position_t null_position = { NULL, 0 };
 126
 127 /* symbols for Microsoft extended-decl-modifier */
 128 static const symbol_t *sym_align      = NULL;
 129 static const symbol_t *sym_allocate   = NULL;
 130 static const symbol_t *sym_dllimport  = NULL;
 131 static const symbol_t *sym_dllexport  = NULL;
 132 static const symbol_t *sym_naked      = NULL;
 133 static const symbol_t *sym_noinline   = NULL;
 134 static const symbol_t *sym_noreturn   = NULL;
 135 static const symbol_t *sym_nothrow    = NULL;
 136 static const symbol_t *sym_novtable   = NULL;
 137 static const symbol_t *sym_property   = NULL;
 138 static const symbol_t *sym_get        = NULL;
 139 static const symbol_t *sym_put        = NULL;
 140 static const symbol_t *sym_selectany  = NULL;
 141 static const symbol_t *sym_thread     = NULL;
 142 static const symbol_t *sym_uuid       = NULL;
 143 static const symbol_t *sym_deprecated = NULL;
 144 static const symbol_t *sym_restrict   = NULL;
 145 static const symbol_t *sym_noalias    = NULL;
 146
 147 /** The token anchor set */
 148 static unsigned char token_anchor_set[T_LAST_TOKEN];
 149
 150 /** The current source position. */
 151 #define HERE (&token.source_position)
 152
 153 static type_t *type_valist;
 154
 155 static statement_t *parse_compound_statement(bool inside_expression_statement);
 156 static statement_t *parse_statement(void);
 157
 158 static expression_t *parse_sub_expression(unsigned precedence);
 159 static expression_t *parse_expression(void);
 160 static type_t       *parse_typename(void);
 161
 162 static void parse_compound_type_entries(declaration_t *compound_declaration);
 163 static declaration_t *parse_declarator(
 164                 const declaration_specifiers_t *specifiers, bool may_be_abstract);
 165 static declaration_t *record_declaration(declaration_t *declaration);
 166
 167 static void semantic_comparison(binary_expression_t *expression);
 168
 169 #define STORAGE_CLASSES     \
 170         case T_typedef:         \
 171         case T_extern:          \
 172         case T_static:          \
 173         case T_auto:            \
 174         case T_register:        \
 175         case T___thread:
 176
 177 #define TYPE_QUALIFIERS     \
 178         case T_const:           \
 179         case T_restrict:        \
 180         case T_volatile:        \
 181         case T_inline:          \
 182         case T__forceinline:    \
 183         case T___attribute__:
 184
 185 #ifdef PROVIDE_COMPLEX
 186 #define COMPLEX_SPECIFIERS  \
 187         case T__Complex:
 188 #define IMAGINARY_SPECIFIERS \
 189         case T__Imaginary:
 190 #else
 191 #define COMPLEX_SPECIFIERS
 192 #define IMAGINARY_SPECIFIERS
 193 #endif
 194
 195 #define TYPE_SPECIFIERS       \
 196         case T_void:              \
 197         case T_char:              \
 198         case T_short:             \
 199         case T_int:               \
 200         case T_long:              \
 201         case T_float:             \
 202         case T_double:            \
 203         case T_signed:            \
 204         case T_unsigned:          \
 205         case T__Bool:             \
 206         case T_struct:            \
 207         case T_union:             \
 208         case T_enum:              \
 209         case T___typeof__:        \
 210         case T___builtin_va_list: \
 211         case T__declspec:         \
 212         COMPLEX_SPECIFIERS        \
 213         IMAGINARY_SPECIFIERS
 214
 215 #define DECLARATION_START   \
 216         STORAGE_CLASSES         \
 217         TYPE_QUALIFIERS         \
 218         TYPE_SPECIFIERS
 219
 220 #define TYPENAME_START      \
 221         TYPE_QUALIFIERS         \
 222         TYPE_SPECIFIERS
 223
 224 /**
 225  * Allocate an AST node with given size and
 226  * initialize all fields with zero.
 227  */
 228 static void *allocate_ast_zero(size_t size)
 229 {
 230         void *res = allocate_ast(size);
 231         memset(res, 0, size);
 232         return res;
 233 }
 234
 235 static declaration_t *allocate_declaration_zero(void)
 236 {
 237         declaration_t *declaration = allocate_ast_zero(sizeof(declaration_t));
 238         declaration->type      = type_error_type;
 239         declaration->alignment = 0;
 240         return declaration;
 241 }
 242
 243 /**
 244  * Returns the size of a statement node.
 245  *
 246  * @param kind  the statement kind
 247  */
 248 static size_t get_statement_struct_size(statement_kind_t kind)
 249 {
 250         static const size_t sizes[] = {
 251                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 252                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 253                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 254                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 255                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 256                 [STATEMENT_IF]          = sizeof(if_statement_t),
 257                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 258                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 259                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 260                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 261                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 262                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 263                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 264                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 265                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 266                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 267                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 268                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 269                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 270         };
 271         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 272         assert(sizes[kind] != 0);
 273         return sizes[kind];
 274 }
 275
 276 /**
 277  * Returns the size of an expression node.
 278  *
 279  * @param kind  the expression kind
 280  */
 281 static size_t get_expression_struct_size(expression_kind_t kind)
 282 {
 283         static const size_t sizes[] = {
 284                 [EXPR_INVALID]                 = sizeof(expression_base_t),
 285                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
 286                 [EXPR_CONST]                   = sizeof(const_expression_t),
 287                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
 288                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
 289                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
 290                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
 291                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
 292                 [EXPR_CALL]                    = sizeof(call_expression_t),
 293                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
 294                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
 295                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
 296                 [EXPR_SELECT]                  = sizeof(select_expression_t),
 297                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
 298                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
 299                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
 300                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
 301                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
 302                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
 303                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
 304                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
 305                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
 306                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
 307                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
 308                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
 309         };
 310         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 311                 return sizes[EXPR_UNARY_FIRST];
 312         }
 313         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 314                 return sizes[EXPR_BINARY_FIRST];
 315         }
 316         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 317         assert(sizes[kind] != 0);
 318         return sizes[kind];
 319 }
 320
 321 /**
 322  * Allocate a statement node of given kind and initialize all
 323  * fields with zero.
 324  */
 325 static statement_t *allocate_statement_zero(statement_kind_t kind)
 326 {
 327         size_t       size = get_statement_struct_size(kind);
 328         statement_t *res  = allocate_ast_zero(size);
 329
 330         res->base.kind   = kind;
 331         res->base.parent = current_parent;
 332         return res;
 333 }
 334
 335 /**
 336  * Allocate an expression node of given kind and initialize all
 337  * fields with zero.
 338  */
 339 static expression_t *allocate_expression_zero(expression_kind_t kind)
 340 {
 341         size_t        size = get_expression_struct_size(kind);
 342         expression_t *res  = allocate_ast_zero(size);
 343
 344         res->base.kind = kind;
 345         res->base.type = type_error_type;
 346         return res;
 347 }
 348
 349 /**
 350  * Creates a new invalid expression.
 351  */
 352 static expression_t *create_invalid_expression(void)
 353 {
 354         expression_t *expression         = allocate_expression_zero(EXPR_INVALID);
 355         expression->base.source_position = token.source_position;
 356         return expression;
 357 }
 358
 359 /**
 360  * Creates a new invalid statement.
 361  */
 362 static statement_t *create_invalid_statement(void)
 363 {
 364         statement_t *statement          = allocate_statement_zero(STATEMENT_INVALID);
 365         statement->base.source_position = token.source_position;
 366         return statement;
 367 }
 368
 369 /**
 370  * Allocate a new empty statement.
 371  */
 372 static statement_t *create_empty_statement(void)
 373 {
 374         statement_t *statement          = allocate_statement_zero(STATEMENT_EMPTY);
 375         statement->base.source_position = token.source_position;
 376         return statement;
 377 }
 378
 379 /**
 380  * Returns the size of a type node.
 381  *
 382  * @param kind  the type kind
 383  */
 384 static size_t get_type_struct_size(type_kind_t kind)
 385 {
 386         static const size_t sizes[] = {
 387                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 388                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 389                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 390                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 391                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 392                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 393                 [TYPE_ENUM]            = sizeof(enum_type_t),
 394                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 395                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 396                 [TYPE_ARRAY]           = sizeof(array_type_t),
 397                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 398                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 399                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 400         };
 401         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 402         assert(kind <= TYPE_TYPEOF);
 403         assert(sizes[kind] != 0);
 404         return sizes[kind];
 405 }
 406
 407 /**
 408  * Allocate a type node of given kind and initialize all
 409  * fields with zero.
 410  *
 411  * @param kind             type kind to allocate
 412  * @param source_position  the source position of the type definition
 413  */
 414 static type_t *allocate_type_zero(type_kind_t kind, const source_position_t *source_position)
 415 {
 416         size_t  size = get_type_struct_size(kind);
 417         type_t *res  = obstack_alloc(type_obst, size);
 418         memset(res, 0, size);
 419
 420         res->base.kind            = kind;
 421         res->base.source_position = *source_position;
 422         return res;
 423 }
 424
 425 /**
 426  * Returns the size of an initializer node.
 427  *
 428  * @param kind  the initializer kind
 429  */
 430 static size_t get_initializer_size(initializer_kind_t kind)
 431 {
 432         static const size_t sizes[] = {
 433                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 434                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 435                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 436                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 437                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 438         };
 439         assert(kind < sizeof(sizes) / sizeof(*sizes));
 440         assert(sizes[kind] != 0);
 441         return sizes[kind];
 442 }
 443
 444 /**
 445  * Allocate an initializer node of given kind and initialize all
 446  * fields with zero.
 447  */
 448 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 449 {
 450         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 451         result->kind          = kind;
 452
 453         return result;
 454 }
 455
 456 /**
 457  * Free a type from the type obstack.
 458  */
 459 static void free_type(void *type)
 460 {
 461         obstack_free(type_obst, type);
 462 }
 463
 464 /**
 465  * Returns the index of the top element of the environment stack.
 466  */
 467 static size_t environment_top(void)
 468 {
 469         return ARR_LEN(environment_stack);
 470 }
 471
 472 /**
 473  * Returns the index of the top element of the label stack.
 474  */
 475 static size_t label_top(void)
 476 {
 477         return ARR_LEN(label_stack);
 478 }
 479
 480 /**
 481  * Return the next token.
 482  */
 483 static inline void next_token(void)
 484 {
 485         token                              = lookahead_buffer[lookahead_bufpos];
 486         lookahead_buffer[lookahead_bufpos] = lexer_token;
 487         lexer_next_token();
 488
 489         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 490
 491 #ifdef PRINT_TOKENS
 492         print_token(stderr, &token);
 493         fprintf(stderr, "\n");
 494 #endif
 495 }
 496
 497 /**
 498  * Return the next token with a given lookahead.
 499  */
 500 static inline const token_t *look_ahead(int num)
 501 {
 502         assert(num > 0 && num <= MAX_LOOKAHEAD);
 503         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 504         return &lookahead_buffer[pos];
 505 }
 506
 507 /**
 508  * Adds a token to the token anchor set (a multi-set).
 509  */
 510 static void add_anchor_token(int token_type)
 511 {
 512         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 513         ++token_anchor_set[token_type];
 514 }
 515
 516 static int save_and_reset_anchor_state(int token_type)
 517 {
 518         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 519         int count = token_anchor_set[token_type];
 520         token_anchor_set[token_type] = 0;
 521         return count;
 522 }
 523
 524 static void restore_anchor_state(int token_type, int count)
 525 {
 526         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 527         token_anchor_set[token_type] = count;
 528 }
 529
 530 /**
 531  * Remove a token from the token anchor set (a multi-set).
 532  */
 533 static void rem_anchor_token(int token_type)
 534 {
 535         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 536         --token_anchor_set[token_type];
 537 }
 538
 539 static bool at_anchor(void)
 540 {
 541         if (token.type < 0)
 542                 return false;
 543         return token_anchor_set[token.type];
 544 }
 545
 546 /**
 547  * Eat tokens until a matching token is found.
 548  */
 549 static void eat_until_matching_token(int type)
 550 {
 551         int end_token;
 552         switch (type) {
 553                 case '(': end_token = ')';  break;
 554                 case '{': end_token = '}';  break;
 555                 case '[': end_token = ']';  break;
 556                 default:  end_token = type; break;
 557         }
 558
 559         unsigned parenthesis_count = 0;
 560         unsigned brace_count       = 0;
 561         unsigned bracket_count     = 0;
 562         while (token.type        != end_token ||
 563                parenthesis_count != 0         ||
 564                brace_count       != 0         ||
 565                bracket_count     != 0) {
 566                 switch (token.type) {
 567                 case T_EOF: return;
 568                 case '(': ++parenthesis_count; break;
 569                 case '{': ++brace_count;       break;
 570                 case '[': ++bracket_count;     break;
 571
 572                 case ')':
 573                         if (parenthesis_count > 0)
 574                                 --parenthesis_count;
 575                         goto check_stop;
 576
 577                 case '}':
 578                         if (brace_count > 0)
 579                                 --brace_count;
 580                         goto check_stop;
 581
 582                 case ']':
 583                         if (bracket_count > 0)
 584                                 --bracket_count;
 585 check_stop:
 586                         if (token.type        == end_token &&
 587                             parenthesis_count == 0         &&
 588                             brace_count       == 0         &&
 589                             bracket_count     == 0)
 590                                 return;
 591                         break;
 592
 593                 default:
 594                         break;
 595                 }
 596                 next_token();
 597         }
 598 }
 599
 600 /**
 601  * Eat input tokens until an anchor is found.
 602  */
 603 static void eat_until_anchor(void)
 604 {
 605         if (token.type == T_EOF)
 606                 return;
 607         while (token_anchor_set[token.type] == 0) {
 608                 if (token.type == '(' || token.type == '{' || token.type == '[')
 609                         eat_until_matching_token(token.type);
 610                 if (token.type == T_EOF)
 611                         break;
 612                 next_token();
 613         }
 614 }
 615
 616 static void eat_block(void)
 617 {
 618         eat_until_matching_token('{');
 619         if (token.type == '}')
 620                 next_token();
 621 }
 622
 623 /**
 624  * eat all token until a ';' is reached or a stop token is found.
 625  */
 626 static void eat_statement(void)
 627 {
 628         eat_until_matching_token(';');
 629         if (token.type == ';')
 630                 next_token();
 631 }
 632
 633 #define eat(token_type)  do { assert(token.type == token_type); next_token(); } while (0)
 634
 635 /**
 636  * Report a parse error because an expected token was not found.
 637  */
 638 static
 639 #if defined __GNUC__ && __GNUC__ >= 4
 640 __attribute__((sentinel))
 641 #endif
 642 void parse_error_expected(const char *message, ...)
 643 {
 644         if (message != NULL) {
 645                 errorf(HERE, "%s", message);
 646         }
 647         va_list ap;
 648         va_start(ap, message);
 649         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 650         va_end(ap);
 651 }
 652
 653 /**
 654  * Report a type error.
 655  */
 656 static void type_error(const char *msg, const source_position_t *source_position,
 657                        type_t *type)
 658 {
 659         errorf(source_position, "%s, but found type '%T'", msg, type);
 660 }
 661
 662 /**
 663  * Report an incompatible type.
 664  */
 665 static void type_error_incompatible(const char *msg,
 666                 const source_position_t *source_position, type_t *type1, type_t *type2)
 667 {
 668         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 669                msg, type1, type2);
 670 }
 671
 672 /**
 673  * Expect the the current token is the expected token.
 674  * If not, generate an error, eat the current statement,
 675  * and goto the end_error label.
 676  */
 677 #define expect(expected)                              \
 678         do {                                              \
 679     if (UNLIKELY(token.type != (expected))) {          \
 680         parse_error_expected(NULL, (expected), NULL); \
 681                 add_anchor_token(expected);                   \
 682         eat_until_anchor();                           \
 683         if (token.type == expected)                   \
 684                 next_token();                             \
 685                 rem_anchor_token(expected);                   \
 686         goto end_error;                               \
 687     }                                                 \
 688     next_token();                                     \
 689         } while (0)
 690
 691 static void set_scope(scope_t *new_scope)
 692 {
 693         if (scope != NULL) {
 694                 scope->last_declaration = last_declaration;
 695         }
 696         scope = new_scope;
 697
 698         last_declaration = new_scope->last_declaration;
 699 }
 700
 701 /**
 702  * Search a symbol in a given namespace and returns its declaration or
 703  * NULL if this symbol was not found.
 704  */
 705 static declaration_t *get_declaration(const symbol_t *const symbol,
 706                                       const namespace_t namespc)
 707 {
 708         declaration_t *declaration = symbol->declaration;
 709         for( ; declaration != NULL; declaration = declaration->symbol_next) {
 710                 if (declaration->namespc == namespc)
 711                         return declaration;
 712         }
 713
 714         return NULL;
 715 }
 716
 717 /**
 718  * pushs an environment_entry on the environment stack and links the
 719  * corresponding symbol to the new entry
 720  */
 721 static void stack_push(stack_entry_t **stack_ptr, declaration_t *declaration)
 722 {
 723         symbol_t    *symbol  = declaration->symbol;
 724         namespace_t  namespc = (namespace_t) declaration->namespc;
 725
 726         /* replace/add declaration into declaration list of the symbol */
 727         declaration_t *iter = symbol->declaration;
 728         if (iter == NULL) {
 729                 symbol->declaration = declaration;
 730         } else {
 731                 declaration_t *iter_last = NULL;
 732                 for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 733                         /* replace an entry? */
 734                         if (iter->namespc == namespc) {
 735                                 if (iter_last == NULL) {
 736                                         symbol->declaration = declaration;
 737                                 } else {
 738                                         iter_last->symbol_next = declaration;
 739                                 }
 740                                 declaration->symbol_next = iter->symbol_next;
 741                                 break;
 742                         }
 743                 }
 744                 if (iter == NULL) {
 745                         assert(iter_last->symbol_next == NULL);
 746                         iter_last->symbol_next = declaration;
 747                 }
 748         }
 749
 750         /* remember old declaration */
 751         stack_entry_t entry;
 752         entry.symbol          = symbol;
 753         entry.old_declaration = iter;
 754         entry.namespc         = (unsigned short) namespc;
 755         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 756 }
 757
 758 static void environment_push(declaration_t *declaration)
 759 {
 760         assert(declaration->source_position.input_name != NULL);
 761         assert(declaration->parent_scope != NULL);
 762         stack_push(&environment_stack, declaration);
 763 }
 764
 765 /**
 766  * Push a declaration of the label stack.
 767  *
 768  * @param declaration  the declaration
 769  */
 770 static void label_push(declaration_t *declaration)
 771 {
 772         declaration->parent_scope = &current_function->scope;
 773         stack_push(&label_stack, declaration);
 774 }
 775
 776 /**
 777  * pops symbols from the environment stack until @p new_top is the top element
 778  */
 779 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 780 {
 781         stack_entry_t *stack = *stack_ptr;
 782         size_t         top   = ARR_LEN(stack);
 783         size_t         i;
 784
 785         assert(new_top <= top);
 786         if (new_top == top)
 787                 return;
 788
 789         for(i = top; i > new_top; --i) {
 790                 stack_entry_t *entry = &stack[i - 1];
 791
 792                 declaration_t *old_declaration = entry->old_declaration;
 793                 symbol_t      *symbol          = entry->symbol;
 794                 namespace_t    namespc         = (namespace_t)entry->namespc;
 795
 796                 /* replace/remove declaration */
 797                 declaration_t *declaration = symbol->declaration;
 798                 assert(declaration != NULL);
 799                 if (declaration->namespc == namespc) {
 800                         if (old_declaration == NULL) {
 801                                 symbol->declaration = declaration->symbol_next;
 802                         } else {
 803                                 symbol->declaration = old_declaration;
 804                         }
 805                 } else {
 806                         declaration_t *iter_last = declaration;
 807                         declaration_t *iter      = declaration->symbol_next;
 808                         for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 809                                 /* replace an entry? */
 810                                 if (iter->namespc == namespc) {
 811                                         assert(iter_last != NULL);
 812                                         iter_last->symbol_next = old_declaration;
 813                                         if (old_declaration != NULL) {
 814                                                 old_declaration->symbol_next = iter->symbol_next;
 815                                         }
 816                                         break;
 817                                 }
 818                         }
 819                         assert(iter != NULL);
 820                 }
 821         }
 822
 823         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 824 }
 825
 826 static void environment_pop_to(size_t new_top)
 827 {
 828         stack_pop_to(&environment_stack, new_top);
 829 }
 830
 831 /**
 832  * Pop all entries on the label stack until the new_top
 833  * is reached.
 834  *
 835  * @param new_top  the new stack top
 836  */
 837 static void label_pop_to(size_t new_top)
 838 {
 839         stack_pop_to(&label_stack, new_top);
 840 }
 841
 842
 843 static int get_rank(const type_t *type)
 844 {
 845         assert(!is_typeref(type));
 846         /* The C-standard allows promoting enums to int or unsigned int (see § 7.2.2
 847          * and esp. footnote 108). However we can't fold constants (yet), so we
 848          * can't decide whether unsigned int is possible, while int always works.
 849          * (unsigned int would be preferable when possible... for stuff like
 850          *  struct { enum { ... } bla : 4; } ) */
 851         if (type->kind == TYPE_ENUM)
 852                 return ATOMIC_TYPE_INT;
 853
 854         assert(type->kind == TYPE_ATOMIC);
 855         return type->atomic.akind;
 856 }
 857
 858 static type_t *promote_integer(type_t *type)
 859 {
 860         if (type->kind == TYPE_BITFIELD)
 861                 type = type->bitfield.base_type;
 862
 863         if (get_rank(type) < ATOMIC_TYPE_INT)
 864                 type = type_int;
 865
 866         return type;
 867 }
 868
 869 /**
 870  * Create a cast expression.
 871  *
 872  * @param expression  the expression to cast
 873  * @param dest_type   the destination type
 874  */
 875 static expression_t *create_cast_expression(expression_t *expression,
 876                                             type_t *dest_type)
 877 {
 878         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
 879
 880         cast->unary.value = expression;
 881         cast->base.type   = dest_type;
 882
 883         return cast;
 884 }
 885
 886 /**
 887  * Check if a given expression represents the 0 pointer constant.
 888  */
 889 static bool is_null_pointer_constant(const expression_t *expression)
 890 {
 891         /* skip void* cast */
 892         if (expression->kind == EXPR_UNARY_CAST
 893                         || expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
 894                 expression = expression->unary.value;
 895         }
 896
 897         /* TODO: not correct yet, should be any constant integer expression
 898          * which evaluates to 0 */
 899         if (expression->kind != EXPR_CONST)
 900                 return false;
 901
 902         type_t *const type = skip_typeref(expression->base.type);
 903         if (!is_type_integer(type))
 904                 return false;
 905
 906         return expression->conste.v.int_value == 0;
 907 }
 908
 909 /**
 910  * Create an implicit cast expression.
 911  *
 912  * @param expression  the expression to cast
 913  * @param dest_type   the destination type
 914  */
 915 static expression_t *create_implicit_cast(expression_t *expression,
 916                                           type_t *dest_type)
 917 {
 918         type_t *const source_type = expression->base.type;
 919
 920         if (source_type == dest_type)
 921                 return expression;
 922
 923         return create_cast_expression(expression, dest_type);
 924 }
 925
 926 typedef enum assign_error_t {
 927         ASSIGN_SUCCESS,
 928         ASSIGN_ERROR_INCOMPATIBLE,
 929         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
 930         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
 931         ASSIGN_WARNING_POINTER_FROM_INT,
 932         ASSIGN_WARNING_INT_FROM_POINTER
 933 } assign_error_t;
 934
 935 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
 936                                 const expression_t *const right,
 937                                 const char *context,
 938                                 const source_position_t *source_position)
 939 {
 940         type_t *const orig_type_right = right->base.type;
 941         type_t *const type_left       = skip_typeref(orig_type_left);
 942         type_t *const type_right      = skip_typeref(orig_type_right);
 943
 944         switch (error) {
 945         case ASSIGN_SUCCESS:
 946                 return;
 947         case ASSIGN_ERROR_INCOMPATIBLE:
 948                 errorf(source_position,
 949                        "destination type '%T' in %s is incompatible with type '%T'",
 950                        orig_type_left, context, orig_type_right);
 951                 return;
 952
 953         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
 954                 type_t *points_to_left
 955                         = skip_typeref(type_left->pointer.points_to);
 956                 type_t *points_to_right
 957                         = skip_typeref(type_right->pointer.points_to);
 958
 959                 /* the left type has all qualifiers from the right type */
 960                 unsigned missing_qualifiers
 961                         = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
 962                 errorf(source_position,
 963                        "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointed-to type",
 964                        orig_type_left, context, orig_type_right, missing_qualifiers);
 965                 return;
 966         }
 967
 968         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
 969                 warningf(source_position,
 970                          "destination type '%T' in %s is incompatible with '%E' of type '%T'",
 971                                  orig_type_left, context, right, orig_type_right);
 972                 return;
 973
 974         case ASSIGN_WARNING_POINTER_FROM_INT:
 975                 warningf(source_position,
 976                          "%s makes integer '%T' from pointer '%T' without a cast",
 977                                  context, orig_type_left, orig_type_right);
 978                 return;
 979
 980         case ASSIGN_WARNING_INT_FROM_POINTER:
 981                 warningf(source_position,
 982                                 "%s makes integer '%T' from pointer '%T' without a cast",
 983                                 context, orig_type_left, orig_type_right);
 984                 return;
 985
 986         default:
 987                 panic("invalid error value");
 988         }
 989 }
 990
 991 /** Implements the rules from § 6.5.16.1 */
 992 static assign_error_t semantic_assign(type_t *orig_type_left,
 993                                       const expression_t *const right)
 994 {
 995         type_t *const orig_type_right = right->base.type;
 996         type_t *const type_left       = skip_typeref(orig_type_left);
 997         type_t *const type_right      = skip_typeref(orig_type_right);
 998
 999         if (is_type_pointer(type_left)) {
1000                 if (is_null_pointer_constant(right)) {
1001                         return ASSIGN_SUCCESS;
1002                 } else if (is_type_pointer(type_right)) {
1003                         type_t *points_to_left
1004                                 = skip_typeref(type_left->pointer.points_to);
1005                         type_t *points_to_right
1006                                 = skip_typeref(type_right->pointer.points_to);
1007
1008                         /* the left type has all qualifiers from the right type */
1009                         unsigned missing_qualifiers
1010                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1011                         if (missing_qualifiers != 0) {
1012                                 return ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1013                         }
1014
1015                         points_to_left  = get_unqualified_type(points_to_left);
1016                         points_to_right = get_unqualified_type(points_to_right);
1017
1018                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID) ||
1019                                         is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1020                                 return ASSIGN_SUCCESS;
1021                         }
1022
1023                         if (!types_compatible(points_to_left, points_to_right)) {
1024                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1025                         }
1026
1027                         return ASSIGN_SUCCESS;
1028                 } else if (is_type_integer(type_right)) {
1029                         return ASSIGN_WARNING_POINTER_FROM_INT;
1030                 }
1031         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1032             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1033                 && is_type_pointer(type_right))) {
1034                 return ASSIGN_SUCCESS;
1035         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1036                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1037                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1038                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1039                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1040                         return ASSIGN_SUCCESS;
1041                 }
1042         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1043                 return ASSIGN_WARNING_INT_FROM_POINTER;
1044         }
1045
1046         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1047                 return ASSIGN_SUCCESS;
1048
1049         return ASSIGN_ERROR_INCOMPATIBLE;
1050 }
1051
1052 static expression_t *parse_constant_expression(void)
1053 {
1054         /* start parsing at precedence 7 (conditional expression) */
1055         expression_t *result = parse_sub_expression(7);
1056
1057         if (!is_constant_expression(result)) {
1058                 errorf(&result->base.source_position,
1059                        "expression '%E' is not constant\n", result);
1060         }
1061
1062         return result;
1063 }
1064
1065 static expression_t *parse_assignment_expression(void)
1066 {
1067         /* start parsing at precedence 2 (assignment expression) */
1068         return parse_sub_expression(2);
1069 }
1070
1071 static type_t *make_global_typedef(const char *name, type_t *type)
1072 {
1073         symbol_t *const symbol       = symbol_table_insert(name);
1074
1075         declaration_t *const declaration = allocate_declaration_zero();
1076         declaration->namespc                = NAMESPACE_NORMAL;
1077         declaration->storage_class          = STORAGE_CLASS_TYPEDEF;
1078         declaration->declared_storage_class = STORAGE_CLASS_TYPEDEF;
1079         declaration->type                   = type;
1080         declaration->symbol                 = symbol;
1081         declaration->source_position        = builtin_source_position;
1082
1083         record_declaration(declaration);
1084
1085         type_t *typedef_type               = allocate_type_zero(TYPE_TYPEDEF, &builtin_source_position);
1086         typedef_type->typedeft.declaration = declaration;
1087
1088         return typedef_type;
1089 }
1090
1091 static string_t parse_string_literals(void)
1092 {
1093         assert(token.type == T_STRING_LITERAL);
1094         string_t result = token.v.string;
1095
1096         next_token();
1097
1098         while (token.type == T_STRING_LITERAL) {
1099                 result = concat_strings(&result, &token.v.string);
1100                 next_token();
1101         }
1102
1103         return result;
1104 }
1105
1106 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1107         [GNU_AK_CONST]                  = "const",
1108         [GNU_AK_VOLATILE]               = "volatile",
1109         [GNU_AK_CDECL]                  = "cdecl",
1110         [GNU_AK_STDCALL]                = "stdcall",
1111         [GNU_AK_FASTCALL]               = "fastcall",
1112         [GNU_AK_DEPRECATED]             = "deprecated",
1113         [GNU_AK_NOINLINE]               = "noinline",
1114         [GNU_AK_NORETURN]               = "noreturn",
1115         [GNU_AK_NAKED]                  = "naked",
1116         [GNU_AK_PURE]                   = "pure",
1117         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1118         [GNU_AK_MALLOC]                 = "malloc",
1119         [GNU_AK_WEAK]                   = "weak",
1120         [GNU_AK_CONSTRUCTOR]            = "constructor",
1121         [GNU_AK_DESTRUCTOR]             = "destructor",
1122         [GNU_AK_NOTHROW]                = "nothrow",
1123         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1124         [GNU_AK_COMMON]                 = "common",
1125         [GNU_AK_NOCOMMON]               = "nocommon",
1126         [GNU_AK_PACKED]                 = "packed",
1127         [GNU_AK_SHARED]                 = "shared",
1128         [GNU_AK_NOTSHARED]              = "notshared",
1129         [GNU_AK_USED]                   = "used",
1130         [GNU_AK_UNUSED]                 = "unused",
1131         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1132         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1133         [GNU_AK_LONGCALL]               = "longcall",
1134         [GNU_AK_SHORTCALL]              = "shortcall",
1135         [GNU_AK_LONG_CALL]              = "long_call",
1136         [GNU_AK_SHORT_CALL]             = "short_call",
1137         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1138         [GNU_AK_INTERRUPT]              = "interrupt",
1139         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1140         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1141         [GNU_AK_NESTING]                = "nesting",
1142         [GNU_AK_NEAR]                   = "near",
1143         [GNU_AK_FAR]                    = "far",
1144         [GNU_AK_SIGNAL]                 = "signal",
1145         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1146         [GNU_AK_TINY_DATA]              = "tiny_data",
1147         [GNU_AK_SAVEALL]                = "saveall",
1148         [GNU_AK_FLATTEN]                = "flatten",
1149         [GNU_AK_SSEREGPARM]             = "sseregparm",
1150         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1151         [GNU_AK_RETURN_TWICE]           = "return_twice",
1152         [GNU_AK_MAY_ALIAS]              = "may_alias",
1153         [GNU_AK_MS_STRUCT]              = "ms_struct",
1154         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1155         [GNU_AK_DLLIMPORT]              = "dllimport",
1156         [GNU_AK_DLLEXPORT]              = "dllexport",
1157         [GNU_AK_ALIGNED]                = "aligned",
1158         [GNU_AK_ALIAS]                  = "alias",
1159         [GNU_AK_SECTION]                = "section",
1160         [GNU_AK_FORMAT]                 = "format",
1161         [GNU_AK_FORMAT_ARG]             = "format_arg",
1162         [GNU_AK_WEAKREF]                = "weakref",
1163         [GNU_AK_NONNULL]                = "nonnull",
1164         [GNU_AK_TLS_MODEL]              = "tls_model",
1165         [GNU_AK_VISIBILITY]             = "visibility",
1166         [GNU_AK_REGPARM]                = "regparm",
1167         [GNU_AK_MODE]                   = "mode",
1168         [GNU_AK_MODEL]                  = "model",
1169         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1170         [GNU_AK_SP_SWITCH]              = "sp_switch",
1171         [GNU_AK_SENTINEL]               = "sentinel"
1172 };
1173
1174 /**
1175  * compare two string, ignoring double underscores on the second.
1176  */
1177 static int strcmp_underscore(const char *s1, const char *s2)
1178 {
1179         if (s2[0] == '_' && s2[1] == '_') {
1180                 size_t len2 = strlen(s2);
1181                 size_t len1 = strlen(s1);
1182                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1183                         return strncmp(s1, s2+2, len2-4);
1184                 }
1185         }
1186
1187         return strcmp(s1, s2);
1188 }
1189
1190 /**
1191  * Allocate a new gnu temporal attribute.
1192  */
1193 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1194 {
1195         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1196         attribute->kind            = kind;
1197         attribute->next            = NULL;
1198         attribute->invalid         = false;
1199         attribute->have_arguments  = false;
1200
1201         return attribute;
1202 }
1203
1204 /**
1205  * parse one constant expression argument.
1206  */
1207 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1208 {
1209         expression_t *expression;
1210         add_anchor_token(')');
1211         expression = parse_constant_expression();
1212         rem_anchor_token(')');
1213         expect(')');
1214         attribute->u.argument = fold_constant(expression);
1215         return;
1216 end_error:
1217         attribute->invalid = true;
1218 }
1219
1220 /**
1221  * parse a list of constant expressions arguments.
1222  */
1223 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1224 {
1225         argument_list_t **list = &attribute->u.arguments;
1226         argument_list_t  *entry;
1227         expression_t     *expression;
1228         add_anchor_token(')');
1229         add_anchor_token(',');
1230         while (true) {
1231                 expression = parse_constant_expression();
1232                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1233                 entry->argument = fold_constant(expression);
1234                 entry->next     = NULL;
1235                 *list = entry;
1236                 list = &entry->next;
1237                 if (token.type != ',')
1238                         break;
1239                 next_token();
1240         }
1241         rem_anchor_token(',');
1242         rem_anchor_token(')');
1243         expect(')');
1244         return;
1245 end_error:
1246         attribute->invalid = true;
1247 }
1248
1249 /**
1250  * parse one string literal argument.
1251  */
1252 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1253                                            string_t *string)
1254 {
1255         add_anchor_token('(');
1256         if (token.type != T_STRING_LITERAL) {
1257                 parse_error_expected("while parsing attribute directive",
1258                                      T_STRING_LITERAL, NULL);
1259                 goto end_error;
1260         }
1261         *string = parse_string_literals();
1262         rem_anchor_token('(');
1263         expect(')');
1264         return;
1265 end_error:
1266         attribute->invalid = true;
1267 }
1268
1269 /**
1270  * parse one tls model.
1271  */
1272 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1273 {
1274         static const char *const tls_models[] = {
1275                 "global-dynamic",
1276                 "local-dynamic",
1277                 "initial-exec",
1278                 "local-exec"
1279         };
1280         string_t string = { NULL, 0 };
1281         parse_gnu_attribute_string_arg(attribute, &string);
1282         if (string.begin != NULL) {
1283                 for(size_t i = 0; i < 4; ++i) {
1284                         if (strcmp(tls_models[i], string.begin) == 0) {
1285                                 attribute->u.value = i;
1286                                 return;
1287                         }
1288                 }
1289                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1290         }
1291         attribute->invalid = true;
1292 }
1293
1294 /**
1295  * parse one tls model.
1296  */
1297 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1298 {
1299         static const char *const visibilities[] = {
1300                 "default",
1301                 "protected",
1302                 "hidden",
1303                 "internal"
1304         };
1305         string_t string = { NULL, 0 };
1306         parse_gnu_attribute_string_arg(attribute, &string);
1307         if (string.begin != NULL) {
1308                 for(size_t i = 0; i < 4; ++i) {
1309                         if (strcmp(visibilities[i], string.begin) == 0) {
1310                                 attribute->u.value = i;
1311                                 return;
1312                         }
1313                 }
1314                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1315         }
1316         attribute->invalid = true;
1317 }
1318
1319 /**
1320  * parse one (code) model.
1321  */
1322 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1323 {
1324         static const char *const visibilities[] = {
1325                 "small",
1326                 "medium",
1327                 "large"
1328         };
1329         string_t string = { NULL, 0 };
1330         parse_gnu_attribute_string_arg(attribute, &string);
1331         if (string.begin != NULL) {
1332                 for(int i = 0; i < 3; ++i) {
1333                         if (strcmp(visibilities[i], string.begin) == 0) {
1334                                 attribute->u.value = i;
1335                                 return;
1336                         }
1337                 }
1338                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1339         }
1340         attribute->invalid = true;
1341 }
1342
1343 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1344 {
1345         /* TODO: find out what is allowed here... */
1346
1347         /* at least: byte, word, pointer, list of machine modes
1348          * __XXX___ is interpreted as XXX */
1349         add_anchor_token(')');
1350
1351         if (token.type != T_IDENTIFIER) {
1352                 expect(T_IDENTIFIER);
1353         }
1354
1355         /* This isn't really correct, the backend should provide a list of machine
1356          * specific modes (according to gcc philosophy that is...) */
1357         const char *symbol_str = token.v.symbol->string;
1358         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1359             strcmp_underscore("byte", symbol_str) == 0) {
1360                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1361         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1362                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1363         } else if (strcmp_underscore("SI",      symbol_str) == 0
1364                 || strcmp_underscore("word",    symbol_str) == 0
1365                 || strcmp_underscore("pointer", symbol_str) == 0) {
1366                 attribute->u.akind = ATOMIC_TYPE_INT;
1367         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1368                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1369         } else {
1370                 warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1371                 attribute->invalid = true;
1372         }
1373         next_token();
1374
1375         rem_anchor_token(')');
1376         expect(')');
1377         return;
1378 end_error:
1379         attribute->invalid = true;
1380 }
1381
1382 /**
1383  * parse one interrupt argument.
1384  */
1385 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1386 {
1387         static const char *const interrupts[] = {
1388                 "IRQ",
1389                 "FIQ",
1390                 "SWI",
1391                 "ABORT",
1392                 "UNDEF"
1393         };
1394         string_t string = { NULL, 0 };
1395         parse_gnu_attribute_string_arg(attribute, &string);
1396         if (string.begin != NULL) {
1397                 for(size_t i = 0; i < 5; ++i) {
1398                         if (strcmp(interrupts[i], string.begin) == 0) {
1399                                 attribute->u.value = i;
1400                                 return;
1401                         }
1402                 }
1403                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1404         }
1405         attribute->invalid = true;
1406 }
1407
1408 /**
1409  * parse ( identifier, const expression, const expression )
1410  */
1411 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1412 {
1413         static const char *const format_names[] = {
1414                 "printf",
1415                 "scanf",
1416                 "strftime",
1417                 "strfmon"
1418         };
1419         int i;
1420
1421         if (token.type != T_IDENTIFIER) {
1422                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1423                 goto end_error;
1424         }
1425         const char *name = token.v.symbol->string;
1426         for(i = 0; i < 4; ++i) {
1427                 if (strcmp_underscore(format_names[i], name) == 0)
1428                         break;
1429         }
1430         if (i >= 4) {
1431                 if (warning.attribute)
1432                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1433         }
1434         next_token();
1435
1436         expect(',');
1437         add_anchor_token(')');
1438         add_anchor_token(',');
1439         parse_constant_expression();
1440         rem_anchor_token(',');
1441         rem_anchor_token('(');
1442
1443         expect(',');
1444         add_anchor_token(')');
1445         parse_constant_expression();
1446         rem_anchor_token('(');
1447         expect(')');
1448         return;
1449 end_error:
1450         attribute->u.value = true;
1451 }
1452
1453 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1454 {
1455         if (!attribute->have_arguments)
1456                 return;
1457
1458         /* should have no arguments */
1459         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1460         eat_until_matching_token('(');
1461         /* we have already consumed '(', so we stop before ')', eat it */
1462         eat(')');
1463         attribute->invalid = true;
1464 }
1465
1466 /**
1467  * Parse one GNU attribute.
1468  *
1469  * Note that attribute names can be specified WITH or WITHOUT
1470  * double underscores, ie const or __const__.
1471  *
1472  * The following attributes are parsed without arguments
1473  *  const
1474  *  volatile
1475  *  cdecl
1476  *  stdcall
1477  *  fastcall
1478  *  deprecated
1479  *  noinline
1480  *  noreturn
1481  *  naked
1482  *  pure
1483  *  always_inline
1484  *  malloc
1485  *  weak
1486  *  constructor
1487  *  destructor
1488  *  nothrow
1489  *  transparent_union
1490  *  common
1491  *  nocommon
1492  *  packed
1493  *  shared
1494  *  notshared
1495  *  used
1496  *  unused
1497  *  no_instrument_function
1498  *  warn_unused_result
1499  *  longcall
1500  *  shortcall
1501  *  long_call
1502  *  short_call
1503  *  function_vector
1504  *  interrupt_handler
1505  *  nmi_handler
1506  *  nesting
1507  *  near
1508  *  far
1509  *  signal
1510  *  eightbit_data
1511  *  tiny_data
1512  *  saveall
1513  *  flatten
1514  *  sseregparm
1515  *  externally_visible
1516  *  return_twice
1517  *  may_alias
1518  *  ms_struct
1519  *  gcc_struct
1520  *  dllimport
1521  *  dllexport
1522  *
1523  * The following attributes are parsed with arguments
1524  *  aligned( const expression )
1525  *  alias( string literal )
1526  *  section( string literal )
1527  *  format( identifier, const expression, const expression )
1528  *  format_arg( const expression )
1529  *  tls_model( string literal )
1530  *  visibility( string literal )
1531  *  regparm( const expression )
1532  *  model( string leteral )
1533  *  trap_exit( const expression )
1534  *  sp_switch( string literal )
1535  *
1536  * The following attributes might have arguments
1537  *  weak_ref( string literal )
1538  *  non_null( const expression // ',' )
1539  *  interrupt( string literal )
1540  *  sentinel( constant expression )
1541  */
1542 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1543 {
1544         gnu_attribute_t *head      = *attributes;
1545         gnu_attribute_t *last      = *attributes;
1546         decl_modifiers_t modifiers = 0;
1547         gnu_attribute_t *attribute;
1548
1549         eat(T___attribute__);
1550         expect('(');
1551         expect('(');
1552
1553         if (token.type != ')') {
1554                 /* find the end of the list */
1555                 if (last != NULL) {
1556                         while (last->next != NULL)
1557                                 last = last->next;
1558                 }
1559
1560                 /* non-empty attribute list */
1561                 while (true) {
1562                         const char *name;
1563                         if (token.type == T_const) {
1564                                 name = "const";
1565                         } else if (token.type == T_volatile) {
1566                                 name = "volatile";
1567                         } else if (token.type == T_cdecl) {
1568                                 /* __attribute__((cdecl)), WITH ms mode */
1569                                 name = "cdecl";
1570                         } else if (token.type == T_IDENTIFIER) {
1571                                 const symbol_t *sym = token.v.symbol;
1572                                 name = sym->string;
1573                         } else {
1574                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1575                                 break;
1576                         }
1577
1578                         next_token();
1579
1580                         int i;
1581                         for(i = 0; i < GNU_AK_LAST; ++i) {
1582                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1583                                         break;
1584                         }
1585                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1586
1587                         attribute = NULL;
1588                         if (kind == GNU_AK_LAST) {
1589                                 if (warning.attribute)
1590                                         warningf(HERE, "'%s' attribute directive ignored", name);
1591
1592                                 /* skip possible arguments */
1593                                 if (token.type == '(') {
1594                                         eat_until_matching_token(')');
1595                                 }
1596                         } else {
1597                                 /* check for arguments */
1598                                 attribute = allocate_gnu_attribute(kind);
1599                                 if (token.type == '(') {
1600                                         next_token();
1601                                         if (token.type == ')') {
1602                                                 /* empty args are allowed */
1603                                                 next_token();
1604                                         } else
1605                                                 attribute->have_arguments = true;
1606                                 }
1607
1608                                 switch(kind) {
1609                                 case GNU_AK_CONST:
1610                                 case GNU_AK_VOLATILE:
1611                                 case GNU_AK_NAKED:
1612                                 case GNU_AK_MALLOC:
1613                                 case GNU_AK_WEAK:
1614                                 case GNU_AK_COMMON:
1615                                 case GNU_AK_NOCOMMON:
1616                                 case GNU_AK_SHARED:
1617                                 case GNU_AK_NOTSHARED:
1618                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1619                                 case GNU_AK_WARN_UNUSED_RESULT:
1620                                 case GNU_AK_LONGCALL:
1621                                 case GNU_AK_SHORTCALL:
1622                                 case GNU_AK_LONG_CALL:
1623                                 case GNU_AK_SHORT_CALL:
1624                                 case GNU_AK_FUNCTION_VECTOR:
1625                                 case GNU_AK_INTERRUPT_HANDLER:
1626                                 case GNU_AK_NMI_HANDLER:
1627                                 case GNU_AK_NESTING:
1628                                 case GNU_AK_NEAR:
1629                                 case GNU_AK_FAR:
1630                                 case GNU_AK_SIGNAL:
1631                                 case GNU_AK_EIGTHBIT_DATA:
1632                                 case GNU_AK_TINY_DATA:
1633                                 case GNU_AK_SAVEALL:
1634                                 case GNU_AK_FLATTEN:
1635                                 case GNU_AK_SSEREGPARM:
1636                                 case GNU_AK_EXTERNALLY_VISIBLE:
1637                                 case GNU_AK_RETURN_TWICE:
1638                                 case GNU_AK_MAY_ALIAS:
1639                                 case GNU_AK_MS_STRUCT:
1640                                 case GNU_AK_GCC_STRUCT:
1641                                         goto no_arg;
1642
1643                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1644                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1645                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1646                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1647                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1648                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1649                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1650                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1651                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1652                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1653                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1654                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1655                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1656                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1657                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1658                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1659                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1660
1661                                 case GNU_AK_ALIGNED:
1662                                         /* __align__ may be used without an argument */
1663                                         if (attribute->have_arguments) {
1664                                                 parse_gnu_attribute_const_arg(attribute);
1665                                         }
1666                                         break;
1667
1668                                 case GNU_AK_FORMAT_ARG:
1669                                 case GNU_AK_REGPARM:
1670                                 case GNU_AK_TRAP_EXIT:
1671                                         if (!attribute->have_arguments) {
1672                                                 /* should have arguments */
1673                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1674                                                 attribute->invalid = true;
1675                                         } else
1676                                                 parse_gnu_attribute_const_arg(attribute);
1677                                         break;
1678                                 case GNU_AK_ALIAS:
1679                                 case GNU_AK_SECTION:
1680                                 case GNU_AK_SP_SWITCH:
1681                                         if (!attribute->have_arguments) {
1682                                                 /* should have arguments */
1683                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1684                                                 attribute->invalid = true;
1685                                         } else
1686                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1687                                         break;
1688                                 case GNU_AK_FORMAT:
1689                                         if (!attribute->have_arguments) {
1690                                                 /* should have arguments */
1691                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1692                                                 attribute->invalid = true;
1693                                         } else
1694                                                 parse_gnu_attribute_format_args(attribute);
1695                                         break;
1696                                 case GNU_AK_WEAKREF:
1697                                         /* may have one string argument */
1698                                         if (attribute->have_arguments)
1699                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1700                                         break;
1701                                 case GNU_AK_NONNULL:
1702                                         if (attribute->have_arguments)
1703                                                 parse_gnu_attribute_const_arg_list(attribute);
1704                                         break;
1705                                 case GNU_AK_TLS_MODEL:
1706                                         if (!attribute->have_arguments) {
1707                                                 /* should have arguments */
1708                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1709                                         } else
1710                                                 parse_gnu_attribute_tls_model_arg(attribute);
1711                                         break;
1712                                 case GNU_AK_VISIBILITY:
1713                                         if (!attribute->have_arguments) {
1714                                                 /* should have arguments */
1715                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1716                                         } else
1717                                                 parse_gnu_attribute_visibility_arg(attribute);
1718                                         break;
1719                                 case GNU_AK_MODEL:
1720                                         if (!attribute->have_arguments) {
1721                                                 /* should have arguments */
1722                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1723                                         } else {
1724                                                 parse_gnu_attribute_model_arg(attribute);
1725                                         }
1726                                         break;
1727                                 case GNU_AK_MODE:
1728                                         if (!attribute->have_arguments) {
1729                                                 /* should have arguments */
1730                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1731                                         } else {
1732                                                 parse_gnu_attribute_mode_arg(attribute);
1733                                         }
1734                                         break;
1735                                 case GNU_AK_INTERRUPT:
1736                                         /* may have one string argument */
1737                                         if (attribute->have_arguments)
1738                                                 parse_gnu_attribute_interrupt_arg(attribute);
1739                                         break;
1740                                 case GNU_AK_SENTINEL:
1741                                         /* may have one string argument */
1742                                         if (attribute->have_arguments)
1743                                                 parse_gnu_attribute_const_arg(attribute);
1744                                         break;
1745                                 case GNU_AK_LAST:
1746                                         /* already handled */
1747                                         break;
1748
1749 no_arg:
1750                                         check_no_argument(attribute, name);
1751                                 }
1752                         }
1753                         if (attribute != NULL) {
1754                                 if (last != NULL) {
1755                                         last->next = attribute;
1756                                         last       = attribute;
1757                                 } else {
1758                                         head = last = attribute;
1759                                 }
1760                         }
1761
1762                         if (token.type != ',')
1763                                 break;
1764                         next_token();
1765                 }
1766         }
1767         expect(')');
1768         expect(')');
1769 end_error:
1770         *attributes = head;
1771
1772         return modifiers;
1773 }
1774
1775 /**
1776  * Parse GNU attributes.
1777  */
1778 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1779 {
1780         decl_modifiers_t modifiers = 0;
1781
1782         while (true) {
1783                 switch(token.type) {
1784                 case T___attribute__:
1785                         modifiers |= parse_gnu_attribute(attributes);
1786                         continue;
1787
1788                 case T_asm:
1789                         next_token();
1790                         expect('(');
1791                         if (token.type != T_STRING_LITERAL) {
1792                                 parse_error_expected("while parsing assembler attribute",
1793                                                      T_STRING_LITERAL, NULL);
1794                                 eat_until_matching_token('(');
1795                                 break;
1796                         } else {
1797                                 parse_string_literals();
1798                         }
1799                         expect(')');
1800                         continue;
1801
1802                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1803                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1804                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1805
1806                 case T___thiscall:
1807                         /* TODO record modifier */
1808                         warningf(HERE, "Ignoring declaration modifier %K", &token);
1809                         break;
1810
1811 end_error:
1812                 default: return modifiers;
1813                 }
1814
1815                 next_token();
1816         }
1817 }
1818
1819 static designator_t *parse_designation(void)
1820 {
1821         designator_t *result = NULL;
1822         designator_t *last   = NULL;
1823
1824         while (true) {
1825                 designator_t *designator;
1826                 switch(token.type) {
1827                 case '[':
1828                         designator = allocate_ast_zero(sizeof(designator[0]));
1829                         designator->source_position = token.source_position;
1830                         next_token();
1831                         add_anchor_token(']');
1832                         designator->array_index = parse_constant_expression();
1833                         rem_anchor_token(']');
1834                         expect(']');
1835                         break;
1836                 case '.':
1837                         designator = allocate_ast_zero(sizeof(designator[0]));
1838                         designator->source_position = token.source_position;
1839                         next_token();
1840                         if (token.type != T_IDENTIFIER) {
1841                                 parse_error_expected("while parsing designator",
1842                                                      T_IDENTIFIER, NULL);
1843                                 return NULL;
1844                         }
1845                         designator->symbol = token.v.symbol;
1846                         next_token();
1847                         break;
1848                 default:
1849                         expect('=');
1850                         return result;
1851                 }
1852
1853                 assert(designator != NULL);
1854                 if (last != NULL) {
1855                         last->next = designator;
1856                 } else {
1857                         result = designator;
1858                 }
1859                 last = designator;
1860         }
1861 end_error:
1862         return NULL;
1863 }
1864
1865 static initializer_t *initializer_from_string(array_type_t *type,
1866                                               const string_t *const string)
1867 {
1868         /* TODO: check len vs. size of array type */
1869         (void) type;
1870
1871         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
1872         initializer->string.string = *string;
1873
1874         return initializer;
1875 }
1876
1877 static initializer_t *initializer_from_wide_string(array_type_t *const type,
1878                                                    wide_string_t *const string)
1879 {
1880         /* TODO: check len vs. size of array type */
1881         (void) type;
1882
1883         initializer_t *const initializer =
1884                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
1885         initializer->wide_string.string = *string;
1886
1887         return initializer;
1888 }
1889
1890 /**
1891  * Build an initializer from a given expression.
1892  */
1893 static initializer_t *initializer_from_expression(type_t *orig_type,
1894                                                   expression_t *expression)
1895 {
1896         /* TODO check that expression is a constant expression */
1897
1898         /* § 6.7.8.14/15 char array may be initialized by string literals */
1899         type_t *type           = skip_typeref(orig_type);
1900         type_t *expr_type_orig = expression->base.type;
1901         type_t *expr_type      = skip_typeref(expr_type_orig);
1902         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
1903                 array_type_t *const array_type   = &type->array;
1904                 type_t       *const element_type = skip_typeref(array_type->element_type);
1905
1906                 if (element_type->kind == TYPE_ATOMIC) {
1907                         atomic_type_kind_t akind = element_type->atomic.akind;
1908                         switch (expression->kind) {
1909                                 case EXPR_STRING_LITERAL:
1910                                         if (akind == ATOMIC_TYPE_CHAR
1911                                                         || akind == ATOMIC_TYPE_SCHAR
1912                                                         || akind == ATOMIC_TYPE_UCHAR) {
1913                                                 return initializer_from_string(array_type,
1914                                                         &expression->string.value);
1915                                         }
1916
1917                                 case EXPR_WIDE_STRING_LITERAL: {
1918                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
1919                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
1920                                                 return initializer_from_wide_string(array_type,
1921                                                         &expression->wide_string.value);
1922                                         }
1923                                 }
1924
1925                                 default:
1926                                         break;
1927                         }
1928                 }
1929         }
1930
1931         assign_error_t error = semantic_assign(type, expression);
1932         if (error == ASSIGN_ERROR_INCOMPATIBLE)
1933                 return NULL;
1934         report_assign_error(error, type, expression, "initializer",
1935                             &expression->base.source_position);
1936
1937         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
1938         result->value.value = create_implicit_cast(expression, type);
1939
1940         return result;
1941 }
1942
1943 /**
1944  * Checks if a given expression can be used as an constant initializer.
1945  */
1946 static bool is_initializer_constant(const expression_t *expression)
1947 {
1948         return is_constant_expression(expression)
1949                 || is_address_constant(expression);
1950 }
1951
1952 /**
1953  * Parses an scalar initializer.
1954  *
1955  * § 6.7.8.11; eat {} without warning
1956  */
1957 static initializer_t *parse_scalar_initializer(type_t *type,
1958                                                bool must_be_constant)
1959 {
1960         /* there might be extra {} hierarchies */
1961         int braces = 0;
1962         if (token.type == '{') {
1963                 warningf(HERE, "extra curly braces around scalar initializer");
1964                 do {
1965                         ++braces;
1966                         next_token();
1967                 } while (token.type == '{');
1968         }
1969
1970         expression_t *expression = parse_assignment_expression();
1971         if (must_be_constant && !is_initializer_constant(expression)) {
1972                 errorf(&expression->base.source_position,
1973                        "Initialisation expression '%E' is not constant\n",
1974                        expression);
1975         }
1976
1977         initializer_t *initializer = initializer_from_expression(type, expression);
1978
1979         if (initializer == NULL) {
1980                 errorf(&expression->base.source_position,
1981                        "expression '%E' (type '%T') doesn't match expected type '%T'",
1982                        expression, expression->base.type, type);
1983                 /* TODO */
1984                 return NULL;
1985         }
1986
1987         bool additional_warning_displayed = false;
1988         while (braces > 0) {
1989                 if (token.type == ',') {
1990                         next_token();
1991                 }
1992                 if (token.type != '}') {
1993                         if (!additional_warning_displayed) {
1994                                 warningf(HERE, "additional elements in scalar initializer");
1995                                 additional_warning_displayed = true;
1996                         }
1997                 }
1998                 eat_block();
1999                 braces--;
2000         }
2001
2002         return initializer;
2003 }
2004
2005 /**
2006  * An entry in the type path.
2007  */
2008 typedef struct type_path_entry_t type_path_entry_t;
2009 struct type_path_entry_t {
2010         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2011         union {
2012                 size_t         index;          /**< For array types: the current index. */
2013                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2014         } v;
2015 };
2016
2017 /**
2018  * A type path expression a position inside compound or array types.
2019  */
2020 typedef struct type_path_t type_path_t;
2021 struct type_path_t {
2022         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2023         type_t            *top_type;     /**< type of the element the path points */
2024         size_t             max_index;    /**< largest index in outermost array */
2025 };
2026
2027 /**
2028  * Prints a type path for debugging.
2029  */
2030 static __attribute__((unused)) void debug_print_type_path(
2031                 const type_path_t *path)
2032 {
2033         size_t len = ARR_LEN(path->path);
2034
2035         for(size_t i = 0; i < len; ++i) {
2036                 const type_path_entry_t *entry = & path->path[i];
2037
2038                 type_t *type = skip_typeref(entry->type);
2039                 if (is_type_compound(type)) {
2040                         /* in gcc mode structs can have no members */
2041                         if (entry->v.compound_entry == NULL) {
2042                                 assert(i == len-1);
2043                                 continue;
2044                         }
2045                         fprintf(stderr, ".%s", entry->v.compound_entry->symbol->string);
2046                 } else if (is_type_array(type)) {
2047                         fprintf(stderr, "[%zu]", entry->v.index);
2048                 } else {
2049                         fprintf(stderr, "-INVALID-");
2050                 }
2051         }
2052         if (path->top_type != NULL) {
2053                 fprintf(stderr, "  (");
2054                 print_type(path->top_type);
2055                 fprintf(stderr, ")");
2056         }
2057 }
2058
2059 /**
2060  * Return the top type path entry, ie. in a path
2061  * (type).a.b returns the b.
2062  */
2063 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2064 {
2065         size_t len = ARR_LEN(path->path);
2066         assert(len > 0);
2067         return &path->path[len-1];
2068 }
2069
2070 /**
2071  * Enlarge the type path by an (empty) element.
2072  */
2073 static type_path_entry_t *append_to_type_path(type_path_t *path)
2074 {
2075         size_t len = ARR_LEN(path->path);
2076         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2077
2078         type_path_entry_t *result = & path->path[len];
2079         memset(result, 0, sizeof(result[0]));
2080         return result;
2081 }
2082
2083 /**
2084  * Descending into a sub-type. Enter the scope of the current
2085  * top_type.
2086  */
2087 static void descend_into_subtype(type_path_t *path)
2088 {
2089         type_t *orig_top_type = path->top_type;
2090         type_t *top_type      = skip_typeref(orig_top_type);
2091
2092         assert(is_type_compound(top_type) || is_type_array(top_type));
2093
2094         type_path_entry_t *top = append_to_type_path(path);
2095         top->type              = top_type;
2096
2097         if (is_type_compound(top_type)) {
2098                 declaration_t *declaration = top_type->compound.declaration;
2099                 declaration_t *entry       = declaration->scope.declarations;
2100                 top->v.compound_entry      = entry;
2101
2102                 if (entry != NULL) {
2103                         path->top_type         = entry->type;
2104                 } else {
2105                         path->top_type         = NULL;
2106                 }
2107         } else {
2108                 assert(is_type_array(top_type));
2109
2110                 top->v.index   = 0;
2111                 path->top_type = top_type->array.element_type;
2112         }
2113 }
2114
2115 /**
2116  * Pop an entry from the given type path, ie. returning from
2117  * (type).a.b to (type).a
2118  */
2119 static void ascend_from_subtype(type_path_t *path)
2120 {
2121         type_path_entry_t *top = get_type_path_top(path);
2122
2123         path->top_type = top->type;
2124
2125         size_t len = ARR_LEN(path->path);
2126         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2127 }
2128
2129 /**
2130  * Pop entries from the given type path until the given
2131  * path level is reached.
2132  */
2133 static void ascend_to(type_path_t *path, size_t top_path_level)
2134 {
2135         size_t len = ARR_LEN(path->path);
2136
2137         while (len > top_path_level) {
2138                 ascend_from_subtype(path);
2139                 len = ARR_LEN(path->path);
2140         }
2141 }
2142
2143 static bool walk_designator(type_path_t *path, const designator_t *designator,
2144                             bool used_in_offsetof)
2145 {
2146         for( ; designator != NULL; designator = designator->next) {
2147                 type_path_entry_t *top       = get_type_path_top(path);
2148                 type_t            *orig_type = top->type;
2149
2150                 type_t *type = skip_typeref(orig_type);
2151
2152                 if (designator->symbol != NULL) {
2153                         symbol_t *symbol = designator->symbol;
2154                         if (!is_type_compound(type)) {
2155                                 if (is_type_valid(type)) {
2156                                         errorf(&designator->source_position,
2157                                                "'.%Y' designator used for non-compound type '%T'",
2158                                                symbol, orig_type);
2159                                 }
2160                                 goto failed;
2161                         }
2162
2163                         declaration_t *declaration = type->compound.declaration;
2164                         declaration_t *iter        = declaration->scope.declarations;
2165                         for( ; iter != NULL; iter = iter->next) {
2166                                 if (iter->symbol == symbol) {
2167                                         break;
2168                                 }
2169                         }
2170                         if (iter == NULL) {
2171                                 errorf(&designator->source_position,
2172                                        "'%T' has no member named '%Y'", orig_type, symbol);
2173                                 goto failed;
2174                         }
2175                         if (used_in_offsetof) {
2176                                 type_t *real_type = skip_typeref(iter->type);
2177                                 if (real_type->kind == TYPE_BITFIELD) {
2178                                         errorf(&designator->source_position,
2179                                                "offsetof designator '%Y' may not specify bitfield",
2180                                                symbol);
2181                                         goto failed;
2182                                 }
2183                         }
2184
2185                         top->type             = orig_type;
2186                         top->v.compound_entry = iter;
2187                         orig_type             = iter->type;
2188                 } else {
2189                         expression_t *array_index = designator->array_index;
2190                         assert(designator->array_index != NULL);
2191
2192                         if (!is_type_array(type)) {
2193                                 if (is_type_valid(type)) {
2194                                         errorf(&designator->source_position,
2195                                                "[%E] designator used for non-array type '%T'",
2196                                                array_index, orig_type);
2197                                 }
2198                                 goto failed;
2199                         }
2200                         if (!is_type_valid(array_index->base.type)) {
2201                                 goto failed;
2202                         }
2203
2204                         long index = fold_constant(array_index);
2205                         if (!used_in_offsetof) {
2206                                 if (index < 0) {
2207                                         errorf(&designator->source_position,
2208                                                "array index [%E] must be positive", array_index);
2209                                         goto failed;
2210                                 }
2211                                 if (type->array.size_constant == true) {
2212                                         long array_size = type->array.size;
2213                                         if (index >= array_size) {
2214                                                 errorf(&designator->source_position,
2215                                                        "designator [%E] (%d) exceeds array size %d",
2216                                                        array_index, index, array_size);
2217                                                 goto failed;
2218                                         }
2219                                 }
2220                         }
2221
2222                         top->type    = orig_type;
2223                         top->v.index = (size_t) index;
2224                         orig_type    = type->array.element_type;
2225                 }
2226                 path->top_type = orig_type;
2227
2228                 if (designator->next != NULL) {
2229                         descend_into_subtype(path);
2230                 }
2231         }
2232         return true;
2233
2234 failed:
2235         return false;
2236 }
2237
2238 static void advance_current_object(type_path_t *path, size_t top_path_level)
2239 {
2240         type_path_entry_t *top = get_type_path_top(path);
2241
2242         type_t *type = skip_typeref(top->type);
2243         if (is_type_union(type)) {
2244                 /* in unions only the first element is initialized */
2245                 top->v.compound_entry = NULL;
2246         } else if (is_type_struct(type)) {
2247                 declaration_t *entry = top->v.compound_entry;
2248
2249                 entry                 = entry->next;
2250                 top->v.compound_entry = entry;
2251                 if (entry != NULL) {
2252                         path->top_type = entry->type;
2253                         return;
2254                 }
2255         } else {
2256                 assert(is_type_array(type));
2257
2258                 top->v.index++;
2259
2260                 if (!type->array.size_constant || top->v.index < type->array.size) {
2261                         return;
2262                 }
2263         }
2264
2265         /* we're past the last member of the current sub-aggregate, try if we
2266          * can ascend in the type hierarchy and continue with another subobject */
2267         size_t len = ARR_LEN(path->path);
2268
2269         if (len > top_path_level) {
2270                 ascend_from_subtype(path);
2271                 advance_current_object(path, top_path_level);
2272         } else {
2273                 path->top_type = NULL;
2274         }
2275 }
2276
2277 /**
2278  * skip until token is found.
2279  */
2280 static void skip_until(int type)
2281 {
2282         while (token.type != type) {
2283                 if (token.type == T_EOF)
2284                         return;
2285                 next_token();
2286         }
2287 }
2288
2289 /**
2290  * skip any {...} blocks until a closing bracket is reached.
2291  */
2292 static void skip_initializers(void)
2293 {
2294         if (token.type == '{')
2295                 next_token();
2296
2297         while (token.type != '}') {
2298                 if (token.type == T_EOF)
2299                         return;
2300                 if (token.type == '{') {
2301                         eat_block();
2302                         continue;
2303                 }
2304                 next_token();
2305         }
2306 }
2307
2308 static initializer_t *create_empty_initializer(void)
2309 {
2310         static initializer_t empty_initializer
2311                 = { .list = { { INITIALIZER_LIST }, 0 } };
2312         return &empty_initializer;
2313 }
2314
2315 /**
2316  * Parse a part of an initialiser for a struct or union,
2317  */
2318 static initializer_t *parse_sub_initializer(type_path_t *path,
2319                 type_t *outer_type, size_t top_path_level,
2320                 parse_initializer_env_t *env)
2321 {
2322         if (token.type == '}') {
2323                 /* empty initializer */
2324                 return create_empty_initializer();
2325         }
2326
2327         type_t *orig_type = path->top_type;
2328         type_t *type      = NULL;
2329
2330         if (orig_type == NULL) {
2331                 /* We are initializing an empty compound. */
2332         } else {
2333                 type = skip_typeref(orig_type);
2334
2335                 /* we can't do usefull stuff if we didn't even parse the type. Skip the
2336                  * initializers in this case. */
2337                 if (!is_type_valid(type)) {
2338                         skip_initializers();
2339                         return create_empty_initializer();
2340                 }
2341         }
2342
2343         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2344
2345         while (true) {
2346                 designator_t *designator = NULL;
2347                 if (token.type == '.' || token.type == '[') {
2348                         designator = parse_designation();
2349                         goto finish_designator;
2350                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2351                         /* GNU-style designator ("identifier: value") */
2352                         designator = allocate_ast_zero(sizeof(designator[0]));
2353                         designator->source_position = token.source_position;
2354                         designator->symbol          = token.v.symbol;
2355                         eat(T_IDENTIFIER);
2356                         eat(':');
2357
2358 finish_designator:
2359                         /* reset path to toplevel, evaluate designator from there */
2360                         ascend_to(path, top_path_level);
2361                         if (!walk_designator(path, designator, false)) {
2362                                 /* can't continue after designation error */
2363                                 goto end_error;
2364                         }
2365
2366                         initializer_t *designator_initializer
2367                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2368                         designator_initializer->designator.designator = designator;
2369                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2370
2371                         orig_type = path->top_type;
2372                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2373                 }
2374
2375                 initializer_t *sub;
2376
2377                 if (token.type == '{') {
2378                         if (type != NULL && is_type_scalar(type)) {
2379                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2380                         } else {
2381                                 eat('{');
2382                                 if (type == NULL) {
2383                                         if (env->declaration != NULL) {
2384                                                 errorf(HERE, "extra brace group at end of initializer for '%Y'",
2385                                                        env->declaration->symbol);
2386                                         } else {
2387                                                 errorf(HERE, "extra brace group at end of initializer");
2388                                         }
2389                                 } else
2390                                         descend_into_subtype(path);
2391
2392                                 add_anchor_token('}');
2393                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2394                                                             env);
2395                                 rem_anchor_token('}');
2396
2397                                 if (type != NULL) {
2398                                         ascend_from_subtype(path);
2399                                         expect('}');
2400                                 } else {
2401                                         expect('}');
2402                                         goto error_parse_next;
2403                                 }
2404                         }
2405                 } else {
2406                         /* must be an expression */
2407                         expression_t *expression = parse_assignment_expression();
2408
2409                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2410                                 errorf(&expression->base.source_position,
2411                                        "Initialisation expression '%E' is not constant\n",
2412                                        expression);
2413                         }
2414
2415                         if (type == NULL) {
2416                                 /* we are already outside, ... */
2417                                 goto error_excess;
2418                         }
2419
2420                         /* handle { "string" } special case */
2421                         if ((expression->kind == EXPR_STRING_LITERAL
2422                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2423                                         && outer_type != NULL) {
2424                                 sub = initializer_from_expression(outer_type, expression);
2425                                 if (sub != NULL) {
2426                                         if (token.type == ',') {
2427                                                 next_token();
2428                                         }
2429                                         if (token.type != '}') {
2430                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2431                                                                  orig_type);
2432                                         }
2433                                         /* TODO: eat , ... */
2434                                         return sub;
2435                                 }
2436                         }
2437
2438                         /* descend into subtypes until expression matches type */
2439                         while (true) {
2440                                 orig_type = path->top_type;
2441                                 type      = skip_typeref(orig_type);
2442
2443                                 sub = initializer_from_expression(orig_type, expression);
2444                                 if (sub != NULL) {
2445                                         break;
2446                                 }
2447                                 if (!is_type_valid(type)) {
2448                                         goto end_error;
2449                                 }
2450                                 if (is_type_scalar(type)) {
2451                                         errorf(&expression->base.source_position,
2452                                                         "expression '%E' doesn't match expected type '%T'",
2453                                                         expression, orig_type);
2454                                         goto end_error;
2455                                 }
2456
2457                                 descend_into_subtype(path);
2458                         }
2459                 }
2460
2461                 /* update largest index of top array */
2462                 const type_path_entry_t *first      = &path->path[0];
2463                 type_t                  *first_type = first->type;
2464                 first_type                          = skip_typeref(first_type);
2465                 if (is_type_array(first_type)) {
2466                         size_t index = first->v.index;
2467                         if (index > path->max_index)
2468                                 path->max_index = index;
2469                 }
2470
2471                 if (type != NULL) {
2472                         /* append to initializers list */
2473                         ARR_APP1(initializer_t*, initializers, sub);
2474                 } else {
2475 error_excess:
2476                         if (env->declaration != NULL)
2477                                 warningf(HERE, "excess elements in struct initializer for '%Y'",
2478                                  env->declaration->symbol);
2479                         else
2480                                 warningf(HERE, "excess elements in struct initializer");
2481                 }
2482
2483 error_parse_next:
2484                 if (token.type == '}') {
2485                         break;
2486                 }
2487                 expect(',');
2488                 if (token.type == '}') {
2489                         break;
2490                 }
2491
2492                 if (type != NULL) {
2493                         /* advance to the next declaration if we are not at the end */
2494                         advance_current_object(path, top_path_level);
2495                         orig_type = path->top_type;
2496                         if (orig_type != NULL)
2497                                 type = skip_typeref(orig_type);
2498                         else
2499                                 type = NULL;
2500                 }
2501         }
2502
2503         size_t len  = ARR_LEN(initializers);
2504         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2505         initializer_t *result = allocate_ast_zero(size);
2506         result->kind          = INITIALIZER_LIST;
2507         result->list.len      = len;
2508         memcpy(&result->list.initializers, initializers,
2509                len * sizeof(initializers[0]));
2510
2511         DEL_ARR_F(initializers);
2512         ascend_to(path, top_path_level+1);
2513
2514         return result;
2515
2516 end_error:
2517         skip_initializers();
2518         DEL_ARR_F(initializers);
2519         ascend_to(path, top_path_level+1);
2520         return NULL;
2521 }
2522
2523 /**
2524  * Parses an initializer. Parsers either a compound literal
2525  * (env->declaration == NULL) or an initializer of a declaration.
2526  */
2527 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2528 {
2529         type_t        *type   = skip_typeref(env->type);
2530         initializer_t *result = NULL;
2531         size_t         max_index;
2532
2533         if (is_type_scalar(type)) {
2534                 result = parse_scalar_initializer(type, env->must_be_constant);
2535         } else if (token.type == '{') {
2536                 eat('{');
2537
2538                 type_path_t path;
2539                 memset(&path, 0, sizeof(path));
2540                 path.top_type = env->type;
2541                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2542
2543                 descend_into_subtype(&path);
2544
2545                 add_anchor_token('}');
2546                 result = parse_sub_initializer(&path, env->type, 1, env);
2547                 rem_anchor_token('}');
2548
2549                 max_index = path.max_index;
2550                 DEL_ARR_F(path.path);
2551
2552                 expect('}');
2553         } else {
2554                 /* parse_scalar_initializer() also works in this case: we simply
2555                  * have an expression without {} around it */
2556                 result = parse_scalar_initializer(type, env->must_be_constant);
2557         }
2558
2559         /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
2560          * the array type size */
2561         if (is_type_array(type) && type->array.size_expression == NULL
2562                         && result != NULL) {
2563                 size_t size;
2564                 switch (result->kind) {
2565                 case INITIALIZER_LIST:
2566                         size = max_index + 1;
2567                         break;
2568
2569                 case INITIALIZER_STRING:
2570                         size = result->string.string.size;
2571                         break;
2572
2573                 case INITIALIZER_WIDE_STRING:
2574                         size = result->wide_string.string.size;
2575                         break;
2576
2577                 case INITIALIZER_DESIGNATOR:
2578                 case INITIALIZER_VALUE:
2579                         /* can happen for parse errors */
2580                         size = 0;
2581                         break;
2582
2583                 default:
2584                         internal_errorf(HERE, "invalid initializer type");
2585                 }
2586
2587                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2588                 cnst->base.type          = type_size_t;
2589                 cnst->conste.v.int_value = size;
2590
2591                 type_t *new_type = duplicate_type(type);
2592
2593                 new_type->array.size_expression = cnst;
2594                 new_type->array.size_constant   = true;
2595                 new_type->array.size            = size;
2596                 env->type = new_type;
2597         }
2598
2599         return result;
2600 end_error:
2601         return NULL;
2602 }
2603
2604 static declaration_t *append_declaration(declaration_t *declaration);
2605
2606 static declaration_t *parse_compound_type_specifier(bool is_struct)
2607 {
2608         gnu_attribute_t  *attributes = NULL;
2609         decl_modifiers_t  modifiers  = 0;
2610         if (is_struct) {
2611                 eat(T_struct);
2612         } else {
2613                 eat(T_union);
2614         }
2615
2616         symbol_t      *symbol      = NULL;
2617         declaration_t *declaration = NULL;
2618
2619         if (token.type == T___attribute__) {
2620                 modifiers |= parse_attributes(&attributes);
2621         }
2622
2623         if (token.type == T_IDENTIFIER) {
2624                 symbol = token.v.symbol;
2625                 next_token();
2626
2627                 namespace_t const namespc =
2628                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
2629                 declaration = get_declaration(symbol, namespc);
2630                 if (declaration != NULL) {
2631                         if (declaration->parent_scope != scope &&
2632                             (token.type == '{' || token.type == ';')) {
2633                                 declaration = NULL;
2634                         } else if (declaration->init.complete &&
2635                                    token.type == '{') {
2636                                 assert(symbol != NULL);
2637                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition at %P)",
2638                                        is_struct ? "struct" : "union", symbol,
2639                                        &declaration->source_position);
2640                                 declaration->scope.declarations = NULL;
2641                         }
2642                 }
2643         } else if (token.type != '{') {
2644                 if (is_struct) {
2645                         parse_error_expected("while parsing struct type specifier",
2646                                              T_IDENTIFIER, '{', NULL);
2647                 } else {
2648                         parse_error_expected("while parsing union type specifier",
2649                                              T_IDENTIFIER, '{', NULL);
2650                 }
2651
2652                 return NULL;
2653         }
2654
2655         if (declaration == NULL) {
2656                 declaration = allocate_declaration_zero();
2657                 declaration->namespc         =
2658                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
2659                 declaration->source_position = token.source_position;
2660                 declaration->symbol          = symbol;
2661                 declaration->parent_scope    = scope;
2662                 if (symbol != NULL) {
2663                         environment_push(declaration);
2664                 }
2665                 append_declaration(declaration);
2666         }
2667
2668         if (token.type == '{') {
2669                 declaration->init.complete = true;
2670
2671                 parse_compound_type_entries(declaration);
2672                 modifiers |= parse_attributes(&attributes);
2673         }
2674
2675         declaration->modifiers |= modifiers;
2676         return declaration;
2677 }
2678
2679 static void parse_enum_entries(type_t *const enum_type)
2680 {
2681         eat('{');
2682
2683         if (token.type == '}') {
2684                 next_token();
2685                 errorf(HERE, "empty enum not allowed");
2686                 return;
2687         }
2688
2689         add_anchor_token('}');
2690         do {
2691                 if (token.type != T_IDENTIFIER) {
2692                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
2693                         eat_block();
2694                         rem_anchor_token('}');
2695                         return;
2696                 }
2697
2698                 declaration_t *const entry = allocate_declaration_zero();
2699                 entry->storage_class   = STORAGE_CLASS_ENUM_ENTRY;
2700                 entry->type            = enum_type;
2701                 entry->symbol          = token.v.symbol;
2702                 entry->source_position = token.source_position;
2703                 next_token();
2704
2705                 if (token.type == '=') {
2706                         next_token();
2707                         expression_t *value = parse_constant_expression();
2708
2709                         value = create_implicit_cast(value, enum_type);
2710                         entry->init.enum_value = value;
2711
2712                         /* TODO semantic */
2713                 }
2714
2715                 record_declaration(entry);
2716
2717                 if (token.type != ',')
2718                         break;
2719                 next_token();
2720         } while (token.type != '}');
2721         rem_anchor_token('}');
2722
2723         expect('}');
2724
2725 end_error:
2726         ;
2727 }
2728
2729 static type_t *parse_enum_specifier(void)
2730 {
2731         gnu_attribute_t *attributes = NULL;
2732         declaration_t   *declaration;
2733         symbol_t        *symbol;
2734
2735         eat(T_enum);
2736         if (token.type == T_IDENTIFIER) {
2737                 symbol = token.v.symbol;
2738                 next_token();
2739
2740                 declaration = get_declaration(symbol, NAMESPACE_ENUM);
2741         } else if (token.type != '{') {
2742                 parse_error_expected("while parsing enum type specifier",
2743                                      T_IDENTIFIER, '{', NULL);
2744                 return NULL;
2745         } else {
2746                 declaration = NULL;
2747                 symbol      = NULL;
2748         }
2749
2750         if (declaration == NULL) {
2751                 declaration = allocate_declaration_zero();
2752                 declaration->namespc         = NAMESPACE_ENUM;
2753                 declaration->source_position = token.source_position;
2754                 declaration->symbol          = symbol;
2755                 declaration->parent_scope  = scope;
2756         }
2757
2758         type_t *const type      = allocate_type_zero(TYPE_ENUM, &declaration->source_position);
2759         type->enumt.declaration = declaration;
2760
2761         if (token.type == '{') {
2762                 if (declaration->init.complete) {
2763                         errorf(HERE, "multiple definitions of enum %Y", symbol);
2764                 }
2765                 if (symbol != NULL) {
2766                         environment_push(declaration);
2767                 }
2768                 append_declaration(declaration);
2769                 declaration->init.complete = true;
2770
2771                 parse_enum_entries(type);
2772                 parse_attributes(&attributes);
2773         }
2774
2775         return type;
2776 }
2777
2778 /**
2779  * if a symbol is a typedef to another type, return true
2780  */
2781 static bool is_typedef_symbol(symbol_t *symbol)
2782 {
2783         const declaration_t *const declaration =
2784                 get_declaration(symbol, NAMESPACE_NORMAL);
2785         return
2786                 declaration != NULL &&
2787                 declaration->storage_class == STORAGE_CLASS_TYPEDEF;
2788 }
2789
2790 static type_t *parse_typeof(void)
2791 {
2792         eat(T___typeof__);
2793
2794         type_t *type;
2795
2796         expect('(');
2797         add_anchor_token(')');
2798
2799         expression_t *expression  = NULL;
2800
2801 restart:
2802         switch(token.type) {
2803         case T___extension__:
2804                 /* This can be a prefix to a typename or an expression.  We simply eat
2805                  * it now. */
2806                 do {
2807                         next_token();
2808                 } while (token.type == T___extension__);
2809                 goto restart;
2810
2811         case T_IDENTIFIER:
2812                 if (is_typedef_symbol(token.v.symbol)) {
2813                         type = parse_typename();
2814                 } else {
2815                         expression = parse_expression();
2816                         type       = expression->base.type;
2817                 }
2818                 break;
2819
2820         TYPENAME_START
2821                 type = parse_typename();
2822                 break;
2823
2824         default:
2825                 expression = parse_expression();
2826                 type       = expression->base.type;
2827                 break;
2828         }
2829
2830         rem_anchor_token(')');
2831         expect(')');
2832
2833         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF, &expression->base.source_position);
2834         typeof_type->typeoft.expression  = expression;
2835         typeof_type->typeoft.typeof_type = type;
2836
2837         return typeof_type;
2838 end_error:
2839         return NULL;
2840 }
2841
2842 typedef enum specifiers_t {
2843         SPECIFIER_SIGNED    = 1 << 0,
2844         SPECIFIER_UNSIGNED  = 1 << 1,
2845         SPECIFIER_LONG      = 1 << 2,
2846         SPECIFIER_INT       = 1 << 3,
2847         SPECIFIER_DOUBLE    = 1 << 4,
2848         SPECIFIER_CHAR      = 1 << 5,
2849         SPECIFIER_SHORT     = 1 << 6,
2850         SPECIFIER_LONG_LONG = 1 << 7,
2851         SPECIFIER_FLOAT     = 1 << 8,
2852         SPECIFIER_BOOL      = 1 << 9,
2853         SPECIFIER_VOID      = 1 << 10,
2854         SPECIFIER_INT8      = 1 << 11,
2855         SPECIFIER_INT16     = 1 << 12,
2856         SPECIFIER_INT32     = 1 << 13,
2857         SPECIFIER_INT64     = 1 << 14,
2858         SPECIFIER_INT128    = 1 << 15,
2859         SPECIFIER_COMPLEX   = 1 << 16,
2860         SPECIFIER_IMAGINARY = 1 << 17,
2861 } specifiers_t;
2862
2863 static type_t *create_builtin_type(symbol_t *const symbol,
2864                                    type_t *const real_type)
2865 {
2866         type_t *type            = allocate_type_zero(TYPE_BUILTIN, &builtin_source_position);
2867         type->builtin.symbol    = symbol;
2868         type->builtin.real_type = real_type;
2869
2870         type_t *result = typehash_insert(type);
2871         if (type != result) {
2872                 free_type(type);
2873         }
2874
2875         return result;
2876 }
2877
2878 static type_t *get_typedef_type(symbol_t *symbol)
2879 {
2880         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
2881         if (declaration == NULL ||
2882            declaration->storage_class != STORAGE_CLASS_TYPEDEF)
2883                 return NULL;
2884
2885         type_t *type               = allocate_type_zero(TYPE_TYPEDEF, &declaration->source_position);
2886         type->typedeft.declaration = declaration;
2887
2888         return type;
2889 }
2890
2891 /**
2892  * check for the allowed MS alignment values.
2893  */
2894 static bool check_alignment_value(long long intvalue)
2895 {
2896         if (intvalue < 1 || intvalue > 8192) {
2897                 errorf(HERE, "illegal alignment value");
2898                 return false;
2899         }
2900         unsigned v = (unsigned)intvalue;
2901         for(unsigned i = 1; i <= 8192; i += i) {
2902                 if (i == v)
2903                         return true;
2904         }
2905         errorf(HERE, "alignment must be power of two");
2906         return false;
2907 }
2908
2909 #define DET_MOD(name, tag) do { \
2910         if (*modifiers & tag) warningf(HERE, #name " used more than once"); \
2911         *modifiers |= tag; \
2912 } while (0)
2913
2914 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
2915 {
2916         decl_modifiers_t *modifiers = &specifiers->modifiers;
2917
2918         while (true) {
2919                 if (token.type == T_restrict) {
2920                         next_token();
2921                         DET_MOD(restrict, DM_RESTRICT);
2922                         goto end_loop;
2923                 } else if (token.type != T_IDENTIFIER)
2924                         break;
2925                 symbol_t *symbol = token.v.symbol;
2926                 if (symbol == sym_align) {
2927                         next_token();
2928                         expect('(');
2929                         if (token.type != T_INTEGER)
2930                                 goto end_error;
2931                         if (check_alignment_value(token.v.intvalue)) {
2932                                 if (specifiers->alignment != 0)
2933                                         warningf(HERE, "align used more than once");
2934                                 specifiers->alignment = (unsigned char)token.v.intvalue;
2935                         }
2936                         next_token();
2937                         expect(')');
2938                 } else if (symbol == sym_allocate) {
2939                         next_token();
2940                         expect('(');
2941                         if (token.type != T_IDENTIFIER)
2942                                 goto end_error;
2943                         (void)token.v.symbol;
2944                         expect(')');
2945                 } else if (symbol == sym_dllimport) {
2946                         next_token();
2947                         DET_MOD(dllimport, DM_DLLIMPORT);
2948                 } else if (symbol == sym_dllexport) {
2949                         next_token();
2950                         DET_MOD(dllexport, DM_DLLEXPORT);
2951                 } else if (symbol == sym_thread) {
2952                         next_token();
2953                         DET_MOD(thread, DM_THREAD);
2954                 } else if (symbol == sym_naked) {
2955                         next_token();
2956                         DET_MOD(naked, DM_NAKED);
2957                 } else if (symbol == sym_noinline) {
2958                         next_token();
2959                         DET_MOD(noinline, DM_NOINLINE);
2960                 } else if (symbol == sym_noreturn) {
2961                         next_token();
2962                         DET_MOD(noreturn, DM_NORETURN);
2963                 } else if (symbol == sym_nothrow) {
2964                         next_token();
2965                         DET_MOD(nothrow, DM_NOTHROW);
2966                 } else if (symbol == sym_novtable) {
2967                         next_token();
2968                         DET_MOD(novtable, DM_NOVTABLE);
2969                 } else if (symbol == sym_property) {
2970                         next_token();
2971                         expect('(');
2972                         for(;;) {
2973                                 bool is_get = false;
2974                                 if (token.type != T_IDENTIFIER)
2975                                         goto end_error;
2976                                 if (token.v.symbol == sym_get) {
2977                                         is_get = true;
2978                                 } else if (token.v.symbol == sym_put) {
2979                                 } else {
2980                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
2981                                         goto end_error;
2982                                 }
2983                                 next_token();
2984                                 expect('=');
2985                                 if (token.type != T_IDENTIFIER)
2986                                         goto end_error;
2987                                 if (is_get) {
2988                                         if (specifiers->get_property_sym != NULL) {
2989                                                 errorf(HERE, "get property name already specified");
2990                                         } else {
2991                                                 specifiers->get_property_sym = token.v.symbol;
2992                                         }
2993                                 } else {
2994                                         if (specifiers->put_property_sym != NULL) {
2995                                                 errorf(HERE, "put property name already specified");
2996                                         } else {
2997                                                 specifiers->put_property_sym = token.v.symbol;
2998                                         }
2999                                 }
3000                                 next_token();
3001                                 if (token.type == ',') {
3002                                         next_token();
3003                                         continue;
3004                                 }
3005                                 break;
3006                         }
3007                         expect(')');
3008                 } else if (symbol == sym_selectany) {
3009                         next_token();
3010                         DET_MOD(selectany, DM_SELECTANY);
3011                 } else if (symbol == sym_uuid) {
3012                         next_token();
3013                         expect('(');
3014                         if (token.type != T_STRING_LITERAL)
3015                                 goto end_error;
3016                         next_token();
3017                         expect(')');
3018                 } else if (symbol == sym_deprecated) {
3019                         next_token();
3020                         if (specifiers->deprecated != 0)
3021                                 warningf(HERE, "deprecated used more than once");
3022                         specifiers->deprecated = 1;
3023                         if (token.type == '(') {
3024                                 next_token();
3025                                 if (token.type == T_STRING_LITERAL) {
3026                                         specifiers->deprecated_string = token.v.string.begin;
3027                                         next_token();
3028                                 } else {
3029                                         errorf(HERE, "string literal expected");
3030                                 }
3031                                 expect(')');
3032                         }
3033                 } else if (symbol == sym_noalias) {
3034                         next_token();
3035                         DET_MOD(noalias, DM_NOALIAS);
3036                 } else {
3037                         warningf(HERE, "Unknown modifier %Y ignored", token.v.symbol);
3038                         next_token();
3039                         if (token.type == '(')
3040                                 skip_until(')');
3041                 }
3042 end_loop:
3043                 if (token.type == ',')
3044                         next_token();
3045         }
3046 end_error:
3047         return;
3048 }
3049
3050 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3051 {
3052         type_t            *type            = NULL;
3053         type_qualifiers_t  qualifiers      = TYPE_QUALIFIER_NONE;
3054         type_modifiers_t   modifiers       = TYPE_MODIFIER_NONE;
3055         unsigned           type_specifiers = 0;
3056         int                newtype         = 0;
3057
3058         specifiers->source_position = token.source_position;
3059
3060         while (true) {
3061                 specifiers->modifiers
3062                         |= parse_attributes(&specifiers->gnu_attributes);
3063                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3064                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3065
3066                 switch(token.type) {
3067
3068                 /* storage class */
3069 #define MATCH_STORAGE_CLASS(token, class)                                  \
3070                 case token:                                                        \
3071                         if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) { \
3072                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3073                         }                                                              \
3074                         specifiers->declared_storage_class = class;                    \
3075                         next_token();                                                  \
3076                         break;
3077
3078                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3079                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3080                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3081                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3082                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3083
3084                 case T__declspec:
3085                         next_token();
3086                         expect('(');
3087                         add_anchor_token(')');
3088                         parse_microsoft_extended_decl_modifier(specifiers);
3089                         rem_anchor_token(')');
3090                         expect(')');
3091                         break;
3092
3093                 case T___thread:
3094                         switch (specifiers->declared_storage_class) {
3095                         case STORAGE_CLASS_NONE:
3096                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD;
3097                                 break;
3098
3099                         case STORAGE_CLASS_EXTERN:
3100                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_EXTERN;
3101                                 break;
3102
3103                         case STORAGE_CLASS_STATIC:
3104                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_STATIC;
3105                                 break;
3106
3107                         default:
3108                                 errorf(HERE, "multiple storage classes in declaration specifiers");
3109                                 break;
3110                         }
3111                         next_token();
3112                         break;
3113
3114                 /* type qualifiers */
3115 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3116                 case token:                                                     \
3117                         qualifiers |= qualifier;                                    \
3118                         next_token();                                               \
3119                         break
3120
3121                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3122                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3123                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3124                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3125                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3126                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3127                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3128                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3129
3130                 case T___extension__:
3131                         /* TODO */
3132                         next_token();
3133                         break;
3134
3135                 /* type specifiers */
3136 #define MATCH_SPECIFIER(token, specifier, name)                         \
3137                 case token:                                                     \
3138                         next_token();                                               \
3139                         if (type_specifiers & specifier) {                           \
3140                                 errorf(HERE, "multiple " name " type specifiers given"); \
3141                         } else {                                                    \
3142                                 type_specifiers |= specifier;                           \
3143                         }                                                           \
3144                         break
3145
3146                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3147                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3148                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3149                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3150                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3151                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3152                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3153                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3154                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3155                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3156                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3157                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3158                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3159                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3160                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3161                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3162
3163                 case T__forceinline:
3164                         /* only in microsoft mode */
3165                         specifiers->modifiers |= DM_FORCEINLINE;
3166                         /* FALLTHROUGH */
3167
3168                 case T_inline:
3169                         next_token();
3170                         specifiers->is_inline = true;
3171                         break;
3172
3173                 case T_long:
3174                         next_token();
3175                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3176                                 errorf(HERE, "multiple type specifiers given");
3177                         } else if (type_specifiers & SPECIFIER_LONG) {
3178                                 type_specifiers |= SPECIFIER_LONG_LONG;
3179                         } else {
3180                                 type_specifiers |= SPECIFIER_LONG;
3181                         }
3182                         break;
3183
3184                 case T_struct: {
3185                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT, HERE);
3186
3187                         type->compound.declaration = parse_compound_type_specifier(true);
3188                         break;
3189                 }
3190                 case T_union: {
3191                         type = allocate_type_zero(TYPE_COMPOUND_UNION, HERE);
3192                         type->compound.declaration = parse_compound_type_specifier(false);
3193                         if (type->compound.declaration->modifiers & DM_TRANSPARENT_UNION)
3194                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3195                         break;
3196                 }
3197                 case T_enum:
3198                         type = parse_enum_specifier();
3199                         break;
3200                 case T___typeof__:
3201                         type = parse_typeof();
3202                         break;
3203                 case T___builtin_va_list:
3204                         type = duplicate_type(type_valist);
3205                         next_token();
3206                         break;
3207
3208                 case T_IDENTIFIER: {
3209                         /* only parse identifier if we haven't found a type yet */
3210                         if (type != NULL || type_specifiers != 0)
3211                                 goto finish_specifiers;
3212
3213                         type_t *typedef_type = get_typedef_type(token.v.symbol);
3214
3215                         if (typedef_type == NULL)
3216                                 goto finish_specifiers;
3217
3218                         next_token();
3219                         type = typedef_type;
3220                         break;
3221                 }
3222
3223                 /* function specifier */
3224                 default:
3225                         goto finish_specifiers;
3226                 }
3227         }
3228
3229 finish_specifiers:
3230
3231         if (type == NULL) {
3232                 atomic_type_kind_t atomic_type;
3233
3234                 /* match valid basic types */
3235                 switch(type_specifiers) {
3236                 case SPECIFIER_VOID:
3237                         atomic_type = ATOMIC_TYPE_VOID;
3238                         break;
3239                 case SPECIFIER_CHAR:
3240                         atomic_type = ATOMIC_TYPE_CHAR;
3241                         break;
3242                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3243                         atomic_type = ATOMIC_TYPE_SCHAR;
3244                         break;
3245                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3246                         atomic_type = ATOMIC_TYPE_UCHAR;
3247                         break;
3248                 case SPECIFIER_SHORT:
3249                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3250                 case SPECIFIER_SHORT | SPECIFIER_INT:
3251                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3252                         atomic_type = ATOMIC_TYPE_SHORT;
3253                         break;
3254                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3255                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3256                         atomic_type = ATOMIC_TYPE_USHORT;
3257                         break;
3258                 case SPECIFIER_INT:
3259                 case SPECIFIER_SIGNED:
3260                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3261                         atomic_type = ATOMIC_TYPE_INT;
3262                         break;
3263                 case SPECIFIER_UNSIGNED:
3264                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3265                         atomic_type = ATOMIC_TYPE_UINT;
3266                         break;
3267                 case SPECIFIER_LONG:
3268                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3269                 case SPECIFIER_LONG | SPECIFIER_INT:
3270                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3271                         atomic_type = ATOMIC_TYPE_LONG;
3272                         break;
3273                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3274                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3275                         atomic_type = ATOMIC_TYPE_ULONG;
3276                         break;
3277
3278                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3279                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3280                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3281                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3282                         | SPECIFIER_INT:
3283                         atomic_type = ATOMIC_TYPE_LONGLONG;
3284                         goto warn_about_long_long;
3285
3286                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3287                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3288                         | SPECIFIER_INT:
3289                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3290 warn_about_long_long:
3291                         if (warning.long_long) {
3292                                 warningf(&specifiers->source_position,
3293                                          "ISO C90 does not support 'long long'");
3294                         }
3295                         break;
3296
3297                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3298                         atomic_type = unsigned_int8_type_kind;
3299                         break;
3300
3301                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3302                         atomic_type = unsigned_int16_type_kind;
3303                         break;
3304
3305                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3306                         atomic_type = unsigned_int32_type_kind;
3307                         break;
3308
3309                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3310                         atomic_type = unsigned_int64_type_kind;
3311                         break;
3312
3313                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3314                         atomic_type = unsigned_int128_type_kind;
3315                         break;
3316
3317                 case SPECIFIER_INT8:
3318                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3319                         atomic_type = int8_type_kind;
3320                         break;
3321
3322                 case SPECIFIER_INT16:
3323                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3324                         atomic_type = int16_type_kind;
3325                         break;
3326
3327                 case SPECIFIER_INT32:
3328                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3329                         atomic_type = int32_type_kind;
3330                         break;
3331
3332                 case SPECIFIER_INT64:
3333                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3334                         atomic_type = int64_type_kind;
3335                         break;
3336
3337                 case SPECIFIER_INT128:
3338                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3339                         atomic_type = int128_type_kind;
3340                         break;
3341
3342                 case SPECIFIER_FLOAT:
3343                         atomic_type = ATOMIC_TYPE_FLOAT;
3344                         break;
3345                 case SPECIFIER_DOUBLE:
3346                         atomic_type = ATOMIC_TYPE_DOUBLE;
3347                         break;
3348                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3349                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3350                         break;
3351                 case SPECIFIER_BOOL:
3352                         atomic_type = ATOMIC_TYPE_BOOL;
3353                         break;
3354                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3355                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3356                         atomic_type = ATOMIC_TYPE_FLOAT;
3357                         break;
3358                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3359                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3360                         atomic_type = ATOMIC_TYPE_DOUBLE;
3361                         break;
3362                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3363                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3364                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3365                         break;
3366                 default:
3367                         /* invalid specifier combination, give an error message */
3368                         if (type_specifiers == 0) {
3369                                 if (! strict_mode) {
3370                                         if (warning.implicit_int) {
3371                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3372                                         }
3373                                         atomic_type = ATOMIC_TYPE_INT;
3374                                         break;
3375                                 } else {
3376                                         errorf(HERE, "no type specifiers given in declaration");
3377                                 }
3378                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3379                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3380                                 errorf(HERE, "signed and unsigned specifiers gives");
3381                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3382                                 errorf(HERE, "only integer types can be signed or unsigned");
3383                         } else {
3384                                 errorf(HERE, "multiple datatypes in declaration");
3385                         }
3386                         atomic_type = ATOMIC_TYPE_INVALID;
3387                 }
3388
3389                 if (type_specifiers & SPECIFIER_COMPLEX &&
3390                    atomic_type != ATOMIC_TYPE_INVALID) {
3391                         type                = allocate_type_zero(TYPE_COMPLEX, &builtin_source_position);
3392                         type->complex.akind = atomic_type;
3393                 } else if (type_specifiers & SPECIFIER_IMAGINARY &&
3394                           atomic_type != ATOMIC_TYPE_INVALID) {
3395                         type                  = allocate_type_zero(TYPE_IMAGINARY, &builtin_source_position);
3396                         type->imaginary.akind = atomic_type;
3397                 } else {
3398                         type               = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
3399                         type->atomic.akind = atomic_type;
3400                 }
3401                 newtype = 1;
3402         } else {
3403                 if (type_specifiers != 0) {
3404                         errorf(HERE, "multiple datatypes in declaration");
3405                 }
3406         }
3407
3408         /* FIXME: check type qualifiers here */
3409
3410         type->base.qualifiers = qualifiers;
3411         type->base.modifiers  = modifiers;
3412
3413         type_t *result = typehash_insert(type);
3414         if (newtype && result != type) {
3415                 free_type(type);
3416         }
3417
3418         specifiers->type = result;
3419 end_error:
3420         return;
3421 }
3422
3423 static type_qualifiers_t parse_type_qualifiers(void)
3424 {
3425         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3426
3427         while (true) {
3428                 switch(token.type) {
3429                 /* type qualifiers */
3430                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3431                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3432                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3433                 /* microsoft extended type modifiers */
3434                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3435                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3436                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3437                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3438                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3439
3440                 default:
3441                         return qualifiers;
3442                 }
3443         }
3444 }
3445
3446 static declaration_t *parse_identifier_list(void)
3447 {
3448         declaration_t *declarations     = NULL;
3449         declaration_t *last_declaration = NULL;
3450         do {
3451                 declaration_t *const declaration = allocate_declaration_zero();
3452                 declaration->type            = NULL; /* a K&R parameter list has no types, yet */
3453                 declaration->source_position = token.source_position;
3454                 declaration->symbol          = token.v.symbol;
3455                 next_token();
3456
3457                 if (last_declaration != NULL) {
3458                         last_declaration->next = declaration;
3459                 } else {
3460                         declarations = declaration;
3461                 }
3462                 last_declaration = declaration;
3463
3464                 if (token.type != ',') {
3465                         break;
3466                 }
3467                 next_token();
3468         } while (token.type == T_IDENTIFIER);
3469
3470         return declarations;
3471 }
3472
3473 static type_t *automatic_type_conversion(type_t *orig_type);
3474
3475 static void semantic_parameter(declaration_t *declaration)
3476 {
3477         /* TODO: improve error messages */
3478         source_position_t const* const pos = &declaration->source_position;
3479
3480         switch (declaration->declared_storage_class) {
3481                 case STORAGE_CLASS_TYPEDEF:
3482                         errorf(pos, "typedef not allowed in parameter list");
3483                         break;
3484
3485                 /* Allowed storage classes */
3486                 case STORAGE_CLASS_NONE:
3487                 case STORAGE_CLASS_REGISTER:
3488                         break;
3489
3490                 default:
3491                         errorf(pos, "parameter may only have none or register storage class");
3492                         break;
3493         }
3494
3495         type_t *const orig_type = declaration->type;
3496         /* §6.7.5.3(7): Array as last part of a parameter type is just syntactic
3497          * sugar.  Turn it into a pointer.
3498          * §6.7.5.3(8): A declaration of a parameter as ``function returning type''
3499          * shall be adjusted to ``pointer to function returning type'', as in 6.3.2.1.
3500          */
3501         type_t *const type = automatic_type_conversion(orig_type);
3502         declaration->type = type;
3503
3504         if (is_type_incomplete(skip_typeref(type))) {
3505                 errorf(pos, "incomplete type '%T' not allowed for parameter '%Y'",
3506                        orig_type, declaration->symbol);
3507         }
3508 }
3509
3510 static declaration_t *parse_parameter(void)
3511 {
3512         declaration_specifiers_t specifiers;
3513         memset(&specifiers, 0, sizeof(specifiers));
3514
3515         parse_declaration_specifiers(&specifiers);
3516
3517         declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/true);
3518
3519         return declaration;
3520 }
3521
3522 static declaration_t *parse_parameters(function_type_t *type)
3523 {
3524         declaration_t *declarations = NULL;
3525
3526         eat('(');
3527         add_anchor_token(')');
3528         int saved_comma_state = save_and_reset_anchor_state(',');
3529
3530         if (token.type == T_IDENTIFIER) {
3531                 symbol_t *symbol = token.v.symbol;
3532                 if (!is_typedef_symbol(symbol)) {
3533                         type->kr_style_parameters = true;
3534                         declarations = parse_identifier_list();
3535                         goto parameters_finished;
3536                 }
3537         }
3538
3539         if (token.type == ')') {
3540                 type->unspecified_parameters = 1;
3541                 goto parameters_finished;
3542         }
3543
3544         declaration_t        *declaration;
3545         declaration_t        *last_declaration = NULL;
3546         function_parameter_t *parameter;
3547         function_parameter_t *last_parameter = NULL;
3548
3549         while (true) {
3550                 switch(token.type) {
3551                 case T_DOTDOTDOT:
3552                         next_token();
3553                         type->variadic = 1;
3554                         goto parameters_finished;
3555
3556                 case T_IDENTIFIER:
3557                 case T___extension__:
3558                 DECLARATION_START
3559                         declaration = parse_parameter();
3560
3561                         /* func(void) is not a parameter */
3562                         if (last_parameter == NULL
3563                                         && token.type == ')'
3564                                         && declaration->symbol == NULL
3565                                         && skip_typeref(declaration->type) == type_void) {
3566                                 goto parameters_finished;
3567                         }
3568                         semantic_parameter(declaration);
3569
3570                         parameter       = obstack_alloc(type_obst, sizeof(parameter[0]));
3571                         memset(parameter, 0, sizeof(parameter[0]));
3572                         parameter->type = declaration->type;
3573
3574                         if (last_parameter != NULL) {
3575                                 last_declaration->next = declaration;
3576                                 last_parameter->next   = parameter;
3577                         } else {
3578                                 type->parameters = parameter;
3579                                 declarations     = declaration;
3580                         }
3581                         last_parameter   = parameter;
3582                         last_declaration = declaration;
3583                         break;
3584
3585                 default:
3586                         goto parameters_finished;
3587                 }
3588                 if (token.type != ',') {
3589                         goto parameters_finished;
3590                 }
3591                 next_token();
3592         }
3593
3594
3595 parameters_finished:
3596         rem_anchor_token(')');
3597         expect(')');
3598
3599         restore_anchor_state(',', saved_comma_state);
3600         return declarations;
3601
3602 end_error:
3603         restore_anchor_state(',', saved_comma_state);
3604         return NULL;
3605 }
3606
3607 typedef enum construct_type_kind_t {
3608         CONSTRUCT_INVALID,
3609         CONSTRUCT_POINTER,
3610         CONSTRUCT_FUNCTION,
3611         CONSTRUCT_ARRAY
3612 } construct_type_kind_t;
3613
3614 typedef struct construct_type_t construct_type_t;
3615 struct construct_type_t {
3616         construct_type_kind_t  kind;
3617         construct_type_t      *next;
3618 };
3619
3620 typedef struct parsed_pointer_t parsed_pointer_t;
3621 struct parsed_pointer_t {
3622         construct_type_t  construct_type;
3623         type_qualifiers_t type_qualifiers;
3624 };
3625
3626 typedef struct construct_function_type_t construct_function_type_t;
3627 struct construct_function_type_t {
3628         construct_type_t  construct_type;
3629         type_t           *function_type;
3630 };
3631
3632 typedef struct parsed_array_t parsed_array_t;
3633 struct parsed_array_t {
3634         construct_type_t  construct_type;
3635         type_qualifiers_t type_qualifiers;
3636         bool              is_static;
3637         bool              is_variable;
3638         expression_t     *size;
3639 };
3640
3641 typedef struct construct_base_type_t construct_base_type_t;
3642 struct construct_base_type_t {
3643         construct_type_t  construct_type;
3644         type_t           *type;
3645 };
3646
3647 static construct_type_t *parse_pointer_declarator(void)
3648 {
3649         eat('*');
3650
3651         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
3652         memset(pointer, 0, sizeof(pointer[0]));
3653         pointer->construct_type.kind = CONSTRUCT_POINTER;
3654         pointer->type_qualifiers     = parse_type_qualifiers();
3655
3656         return (construct_type_t*) pointer;
3657 }
3658
3659 static construct_type_t *parse_array_declarator(void)
3660 {
3661         eat('[');
3662         add_anchor_token(']');
3663
3664         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
3665         memset(array, 0, sizeof(array[0]));
3666         array->construct_type.kind = CONSTRUCT_ARRAY;
3667
3668         if (token.type == T_static) {
3669                 array->is_static = true;
3670                 next_token();
3671         }
3672
3673         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
3674         if (type_qualifiers != 0) {
3675                 if (token.type == T_static) {
3676                         array->is_static = true;
3677                         next_token();
3678                 }
3679         }
3680         array->type_qualifiers = type_qualifiers;
3681
3682         if (token.type == '*' && look_ahead(1)->type == ']') {
3683                 array->is_variable = true;
3684                 next_token();
3685         } else if (token.type != ']') {
3686                 array->size = parse_assignment_expression();
3687         }
3688
3689         rem_anchor_token(']');
3690         expect(']');
3691
3692         return (construct_type_t*) array;
3693 end_error:
3694         return NULL;
3695 }
3696
3697 static construct_type_t *parse_function_declarator(declaration_t *declaration)
3698 {
3699         type_t *type;
3700         if (declaration != NULL) {
3701                 type = allocate_type_zero(TYPE_FUNCTION, &declaration->source_position);
3702
3703                 unsigned mask = declaration->modifiers & (DM_CDECL|DM_STDCALL|DM_FASTCALL|DM_THISCALL);
3704
3705                 if (mask & (mask-1)) {
3706                         const char *first = NULL, *second = NULL;
3707
3708                         /* more than one calling convention set */
3709                         if (declaration->modifiers & DM_CDECL) {
3710                                 if (first == NULL)       first = "cdecl";
3711                                 else if (second == NULL) second = "cdecl";
3712                         }
3713                         if (declaration->modifiers & DM_STDCALL) {
3714                                 if (first == NULL)       first = "stdcall";
3715                                 else if (second == NULL) second = "stdcall";
3716                         }
3717                         if (declaration->modifiers & DM_FASTCALL) {
3718                                 if (first == NULL)       first = "fastcall";
3719                                 else if (second == NULL) second = "fastcall";
3720                         }
3721                         if (declaration->modifiers & DM_THISCALL) {
3722                                 if (first == NULL)       first = "thiscall";
3723                                 else if (second == NULL) second = "thiscall";
3724                         }
3725                         errorf(&declaration->source_position, "%s and %s attributes are not compatible", first, second);
3726                 }
3727
3728                 if (declaration->modifiers & DM_CDECL)
3729                         type->function.calling_convention = CC_CDECL;
3730                 else if (declaration->modifiers & DM_STDCALL)
3731                         type->function.calling_convention = CC_STDCALL;
3732                 else if (declaration->modifiers & DM_FASTCALL)
3733                         type->function.calling_convention = CC_FASTCALL;
3734                 else if (declaration->modifiers & DM_THISCALL)
3735                         type->function.calling_convention = CC_THISCALL;
3736         } else {
3737                 type = allocate_type_zero(TYPE_FUNCTION, HERE);
3738         }
3739
3740         declaration_t *parameters = parse_parameters(&type->function);
3741         if (declaration != NULL) {
3742                 declaration->scope.declarations = parameters;
3743         }
3744
3745         construct_function_type_t *construct_function_type =
3746                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
3747         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
3748         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
3749         construct_function_type->function_type       = type;
3750
3751         return &construct_function_type->construct_type;
3752 }
3753
3754 static void fix_declaration_type(declaration_t *declaration)
3755 {
3756         decl_modifiers_t declaration_modifiers = declaration->modifiers;
3757         type_modifiers_t type_modifiers        = declaration->type->base.modifiers;
3758
3759         if (declaration_modifiers & DM_TRANSPARENT_UNION)
3760                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3761
3762         if (declaration->type->base.modifiers == type_modifiers)
3763                 return;
3764
3765         type_t *copy = duplicate_type(declaration->type);
3766         copy->base.modifiers = type_modifiers;
3767
3768         type_t *result = typehash_insert(copy);
3769         if (result != copy) {
3770                 obstack_free(type_obst, copy);
3771         }
3772
3773         declaration->type = result;
3774 }
3775
3776 static construct_type_t *parse_inner_declarator(declaration_t *declaration,
3777                 bool may_be_abstract)
3778 {
3779         /* construct a single linked list of construct_type_t's which describe
3780          * how to construct the final declarator type */
3781         construct_type_t *first = NULL;
3782         construct_type_t *last  = NULL;
3783         gnu_attribute_t  *attributes = NULL;
3784
3785         decl_modifiers_t modifiers = parse_attributes(&attributes);
3786
3787         /* pointers */
3788         while (token.type == '*') {
3789                 construct_type_t *type = parse_pointer_declarator();
3790
3791                 if (last == NULL) {
3792                         first = type;
3793                         last  = type;
3794                 } else {
3795                         last->next = type;
3796                         last       = type;
3797                 }
3798
3799                 /* TODO: find out if this is correct */
3800                 modifiers |= parse_attributes(&attributes);
3801         }
3802
3803         if (declaration != NULL)
3804                 declaration->modifiers |= modifiers;
3805
3806         construct_type_t *inner_types = NULL;
3807
3808         switch(token.type) {
3809         case T_IDENTIFIER:
3810                 if (declaration == NULL) {
3811                         errorf(HERE, "no identifier expected in typename");
3812                 } else {
3813                         declaration->symbol          = token.v.symbol;
3814                         declaration->source_position = token.source_position;
3815                 }
3816                 next_token();
3817                 break;
3818         case '(':
3819                 next_token();
3820                 add_anchor_token(')');
3821                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
3822                 rem_anchor_token(')');
3823                 expect(')');
3824                 break;
3825         default:
3826                 if (may_be_abstract)
3827                         break;
3828                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
3829                 /* avoid a loop in the outermost scope, because eat_statement doesn't
3830                  * eat '}' */
3831                 if (token.type == '}' && current_function == NULL) {
3832                         next_token();
3833                 } else {
3834                         eat_statement();
3835                 }
3836                 return NULL;
3837         }
3838
3839         construct_type_t *p = last;
3840
3841         while(true) {
3842                 construct_type_t *type;
3843                 switch(token.type) {
3844                 case '(':
3845                         type = parse_function_declarator(declaration);
3846                         break;
3847                 case '[':
3848                         type = parse_array_declarator();
3849                         break;
3850                 default:
3851                         goto declarator_finished;
3852                 }
3853
3854                 /* insert in the middle of the list (behind p) */
3855                 if (p != NULL) {
3856                         type->next = p->next;
3857                         p->next    = type;
3858                 } else {
3859                         type->next = first;
3860                         first      = type;
3861                 }
3862                 if (last == p) {
3863                         last = type;
3864                 }
3865         }
3866
3867 declarator_finished:
3868         /* append inner_types at the end of the list, we don't to set last anymore
3869          * as it's not needed anymore */
3870         if (last == NULL) {
3871                 assert(first == NULL);
3872                 first = inner_types;
3873         } else {
3874                 last->next = inner_types;
3875         }
3876
3877         return first;
3878 end_error:
3879         return NULL;
3880 }
3881
3882 static void parse_declaration_attributes(declaration_t *declaration)
3883 {
3884         gnu_attribute_t  *attributes = NULL;
3885         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
3886
3887         if (declaration == NULL)
3888                 return;
3889
3890         declaration->modifiers |= modifiers;
3891         /* check if we have these stupid mode attributes... */
3892         type_t *old_type = declaration->type;
3893         if (old_type == NULL)
3894                 return;
3895
3896         gnu_attribute_t *attribute = attributes;
3897         for ( ; attribute != NULL; attribute = attribute->next) {
3898                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
3899                         continue;
3900
3901                 atomic_type_kind_t  akind = attribute->u.akind;
3902                 if (!is_type_signed(old_type)) {
3903                         switch(akind) {
3904                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
3905                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
3906                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
3907                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
3908                         default:
3909                                 panic("invalid akind in mode attribute");
3910                         }
3911                 }
3912                 declaration->type
3913                         = make_atomic_type(akind, old_type->base.qualifiers);
3914         }
3915 }
3916
3917 static type_t *construct_declarator_type(construct_type_t *construct_list,
3918                                          type_t *type)
3919 {
3920         construct_type_t *iter = construct_list;
3921         for( ; iter != NULL; iter = iter->next) {
3922                 switch(iter->kind) {
3923                 case CONSTRUCT_INVALID:
3924                         internal_errorf(HERE, "invalid type construction found");
3925                 case CONSTRUCT_FUNCTION: {
3926                         construct_function_type_t *construct_function_type
3927                                 = (construct_function_type_t*) iter;
3928
3929                         type_t *function_type = construct_function_type->function_type;
3930
3931                         function_type->function.return_type = type;
3932
3933                         type_t *skipped_return_type = skip_typeref(type);
3934                         if (is_type_function(skipped_return_type)) {
3935                                 errorf(HERE, "function returning function is not allowed");
3936                                 type = type_error_type;
3937                         } else if (is_type_array(skipped_return_type)) {
3938                                 errorf(HERE, "function returning array is not allowed");
3939                                 type = type_error_type;
3940                         } else {
3941                                 type = function_type;
3942                         }
3943                         break;
3944                 }
3945
3946                 case CONSTRUCT_POINTER: {
3947                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
3948                         type_t           *pointer_type   = allocate_type_zero(TYPE_POINTER, &null_position);
3949                         pointer_type->pointer.points_to  = type;
3950                         pointer_type->base.qualifiers    = parsed_pointer->type_qualifiers;
3951
3952                         type = pointer_type;
3953                         break;
3954                 }
3955
3956                 case CONSTRUCT_ARRAY: {
3957                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
3958                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY, &null_position);
3959
3960                         expression_t *size_expression = parsed_array->size;
3961                         if (size_expression != NULL) {
3962                                 size_expression
3963                                         = create_implicit_cast(size_expression, type_size_t);
3964                         }
3965
3966                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
3967                         array_type->array.element_type    = type;
3968                         array_type->array.is_static       = parsed_array->is_static;
3969                         array_type->array.is_variable     = parsed_array->is_variable;
3970                         array_type->array.size_expression = size_expression;
3971
3972                         if (size_expression != NULL) {
3973                                 if (is_constant_expression(size_expression)) {
3974                                         array_type->array.size_constant = true;
3975                                         array_type->array.size
3976                                                 = fold_constant(size_expression);
3977                                 } else {
3978                                         array_type->array.is_vla = true;
3979                                 }
3980                         }
3981
3982                         type_t *skipped_type = skip_typeref(type);
3983                         if (is_type_atomic(skipped_type, ATOMIC_TYPE_VOID)) {
3984                                 errorf(HERE, "array of void is not allowed");
3985                                 type = type_error_type;
3986                         } else {
3987                                 type = array_type;
3988                         }
3989                         break;
3990                 }
3991                 }
3992
3993                 type_t *hashed_type = typehash_insert(type);
3994                 if (hashed_type != type) {
3995                         /* the function type was constructed earlier freeing it here will
3996                          * destroy other types... */
3997                         if (iter->kind != CONSTRUCT_FUNCTION) {
3998                                 free_type(type);
3999                         }
4000                         type = hashed_type;
4001                 }
4002         }
4003
4004         return type;
4005 }
4006
4007 static declaration_t *parse_declarator(
4008                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
4009 {
4010         declaration_t *const declaration    = allocate_declaration_zero();
4011         declaration->declared_storage_class = specifiers->declared_storage_class;
4012         declaration->modifiers              = specifiers->modifiers;
4013         declaration->deprecated_string      = specifiers->deprecated_string;
4014         declaration->get_property_sym       = specifiers->get_property_sym;
4015         declaration->put_property_sym       = specifiers->put_property_sym;
4016         declaration->is_inline              = specifiers->is_inline;
4017
4018         declaration->storage_class          = specifiers->declared_storage_class;
4019         if (declaration->storage_class == STORAGE_CLASS_NONE
4020                         && scope != global_scope) {
4021                 declaration->storage_class = STORAGE_CLASS_AUTO;
4022         }
4023
4024         if (specifiers->alignment != 0) {
4025                 /* TODO: add checks here */
4026                 declaration->alignment = specifiers->alignment;
4027         }
4028
4029         construct_type_t *construct_type
4030                 = parse_inner_declarator(declaration, may_be_abstract);
4031         type_t *const type = specifiers->type;
4032         declaration->type = construct_declarator_type(construct_type, type);
4033
4034         parse_declaration_attributes(declaration);
4035
4036         fix_declaration_type(declaration);
4037
4038         if (construct_type != NULL) {
4039                 obstack_free(&temp_obst, construct_type);
4040         }
4041
4042         return declaration;
4043 }
4044
4045 static type_t *parse_abstract_declarator(type_t *base_type)
4046 {
4047         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4048
4049         type_t *result = construct_declarator_type(construct_type, base_type);
4050         if (construct_type != NULL) {
4051                 obstack_free(&temp_obst, construct_type);
4052         }
4053
4054         return result;
4055 }
4056
4057 static declaration_t *append_declaration(declaration_t* const declaration)
4058 {
4059         if (last_declaration != NULL) {
4060                 last_declaration->next = declaration;
4061         } else {
4062                 scope->declarations = declaration;
4063         }
4064         last_declaration = declaration;
4065         return declaration;
4066 }
4067
4068 /**
4069  * Check if the declaration of main is suspicious.  main should be a
4070  * function with external linkage, returning int, taking either zero
4071  * arguments, two, or three arguments of appropriate types, ie.
4072  *
4073  * int main([ int argc, char **argv [, char **env ] ]).
4074  *
4075  * @param decl    the declaration to check
4076  * @param type    the function type of the declaration
4077  */
4078 static void check_type_of_main(const declaration_t *const decl, const function_type_t *const func_type)
4079 {
4080         if (decl->storage_class == STORAGE_CLASS_STATIC) {
4081                 warningf(&decl->source_position,
4082                          "'main' is normally a non-static function");
4083         }
4084         if (skip_typeref(func_type->return_type) != type_int) {
4085                 warningf(&decl->source_position,
4086                          "return type of 'main' should be 'int', but is '%T'",
4087                          func_type->return_type);
4088         }
4089         const function_parameter_t *parm = func_type->parameters;
4090         if (parm != NULL) {
4091                 type_t *const first_type = parm->type;
4092                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4093                         warningf(&decl->source_position,
4094                                  "first argument of 'main' should be 'int', but is '%T'", first_type);
4095                 }
4096                 parm = parm->next;
4097                 if (parm != NULL) {
4098                         type_t *const second_type = parm->type;
4099                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4100                                 warningf(&decl->source_position,
4101                                          "second argument of 'main' should be 'char**', but is '%T'", second_type);
4102                         }
4103                         parm = parm->next;
4104                         if (parm != NULL) {
4105                                 type_t *const third_type = parm->type;
4106                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4107                                         warningf(&decl->source_position,
4108                                                  "third argument of 'main' should be 'char**', but is '%T'", third_type);
4109                                 }
4110                                 parm = parm->next;
4111                                 if (parm != NULL)
4112                                         goto warn_arg_count;
4113                         }
4114                 } else {
4115 warn_arg_count:
4116                         warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
4117                 }
4118         }
4119 }
4120
4121 /**
4122  * Check if a symbol is the equal to "main".
4123  */
4124 static bool is_sym_main(const symbol_t *const sym)
4125 {
4126         return strcmp(sym->string, "main") == 0;
4127 }
4128
4129 static declaration_t *internal_record_declaration(
4130         declaration_t *const declaration,
4131         const bool is_definition)
4132 {
4133         const symbol_t *const symbol  = declaration->symbol;
4134         const namespace_t     namespc = (namespace_t)declaration->namespc;
4135
4136         assert(symbol != NULL);
4137         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4138
4139         type_t *const orig_type = declaration->type;
4140         type_t *const type      = skip_typeref(orig_type);
4141         if (is_type_function(type) &&
4142                         type->function.unspecified_parameters &&
4143                         warning.strict_prototypes &&
4144                         previous_declaration == NULL) {
4145                 warningf(&declaration->source_position,
4146                          "function declaration '%#T' is not a prototype",
4147                          orig_type, declaration->symbol);
4148         }
4149
4150         if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
4151                 check_type_of_main(declaration, &type->function);
4152         }
4153
4154         if (warning.nested_externs                             &&
4155             declaration->storage_class == STORAGE_CLASS_EXTERN &&
4156             scope                      != global_scope) {
4157                 warningf(&declaration->source_position,
4158                          "nested extern declaration of '%#T'", declaration->type, symbol);
4159         }
4160
4161         assert(declaration != previous_declaration);
4162         if (previous_declaration != NULL
4163                         && previous_declaration->parent_scope == scope) {
4164                 /* can happen for K&R style declarations */
4165                 if (previous_declaration->type == NULL) {
4166                         previous_declaration->type = declaration->type;
4167                 }
4168
4169                 const type_t *prev_type = skip_typeref(previous_declaration->type);
4170                 if (!types_compatible(type, prev_type)) {
4171                         errorf(&declaration->source_position,
4172                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
4173                                    orig_type, symbol, previous_declaration->type, symbol,
4174                                    &previous_declaration->source_position);
4175                 } else {
4176                         unsigned old_storage_class = previous_declaration->storage_class;
4177                         if (old_storage_class == STORAGE_CLASS_ENUM_ENTRY) {
4178                                 errorf(&declaration->source_position,
4179                                            "redeclaration of enum entry '%Y' (declared %P)",
4180                                            symbol, &previous_declaration->source_position);
4181                                 return previous_declaration;
4182                         }
4183
4184                         if (warning.redundant_decls                                     &&
4185                             is_definition                                               &&
4186                             previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
4187                             !(previous_declaration->modifiers & DM_USED)                &&
4188                             !previous_declaration->used) {
4189                                 warningf(&previous_declaration->source_position,
4190                                          "unnecessary static forward declaration for '%#T'",
4191                                          previous_declaration->type, symbol);
4192                         }
4193
4194                         unsigned new_storage_class = declaration->storage_class;
4195
4196                         if (is_type_incomplete(prev_type)) {
4197                                 previous_declaration->type = type;
4198                                 prev_type                  = type;
4199                         }
4200
4201                         /* pretend no storage class means extern for function
4202                          * declarations (except if the previous declaration is neither
4203                          * none nor extern) */
4204                         if (is_type_function(type)) {
4205                                 if (prev_type->function.unspecified_parameters) {
4206                                         previous_declaration->type = type;
4207                                         prev_type                  = type;
4208                                 }
4209
4210                                 switch (old_storage_class) {
4211                                 case STORAGE_CLASS_NONE:
4212                                         old_storage_class = STORAGE_CLASS_EXTERN;
4213                                         /* FALLTHROUGH */
4214
4215                                 case STORAGE_CLASS_EXTERN:
4216                                         if (is_definition) {
4217                                                 if (warning.missing_prototypes &&
4218                                                     prev_type->function.unspecified_parameters &&
4219                                                     !is_sym_main(symbol)) {
4220                                                         warningf(&declaration->source_position,
4221                                                                          "no previous prototype for '%#T'",
4222                                                                          orig_type, symbol);
4223                                                 }
4224                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4225                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4226                                         }
4227                                         break;
4228
4229                                 default:
4230                                         break;
4231                                 }
4232                         }
4233
4234                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
4235                                         new_storage_class == STORAGE_CLASS_EXTERN) {
4236 warn_redundant_declaration:
4237                                 if (!is_definition          &&
4238                                     warning.redundant_decls &&
4239                                     strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
4240                                         warningf(&declaration->source_position,
4241                                                  "redundant declaration for '%Y' (declared %P)",
4242                                                  symbol, &previous_declaration->source_position);
4243                                 }
4244                         } else if (current_function == NULL) {
4245                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
4246                                     new_storage_class == STORAGE_CLASS_STATIC) {
4247                                         errorf(&declaration->source_position,
4248                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
4249                                                symbol, &previous_declaration->source_position);
4250                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4251                                         previous_declaration->storage_class          = STORAGE_CLASS_NONE;
4252                                         previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
4253                                 } else {
4254                                         goto warn_redundant_declaration;
4255                                 }
4256                         } else if (old_storage_class == new_storage_class) {
4257                                 errorf(&declaration->source_position,
4258                                        "redeclaration of '%Y' (declared %P)",
4259                                        symbol, &previous_declaration->source_position);
4260                         } else {
4261                                 errorf(&declaration->source_position,
4262                                        "redeclaration of '%Y' with different linkage (declared %P)",
4263                                        symbol, &previous_declaration->source_position);
4264                         }
4265                 }
4266
4267                 previous_declaration->modifiers |= declaration->modifiers;
4268                 previous_declaration->is_inline |= declaration->is_inline;
4269                 return previous_declaration;
4270         } else if (is_type_function(type)) {
4271                 if (is_definition &&
4272                     declaration->storage_class != STORAGE_CLASS_STATIC) {
4273                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4274                                 warningf(&declaration->source_position,
4275                                          "no previous prototype for '%#T'", orig_type, symbol);
4276                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4277                                 warningf(&declaration->source_position,
4278                                          "no previous declaration for '%#T'", orig_type,
4279                                          symbol);
4280                         }
4281                 }
4282         } else {
4283                 if (warning.missing_declarations &&
4284                     scope == global_scope && (
4285                       declaration->storage_class == STORAGE_CLASS_NONE ||
4286                       declaration->storage_class == STORAGE_CLASS_THREAD
4287                     )) {
4288                         warningf(&declaration->source_position,
4289                                  "no previous declaration for '%#T'", orig_type, symbol);
4290                 }
4291         }
4292
4293         assert(declaration->parent_scope == NULL);
4294         assert(scope != NULL);
4295
4296         declaration->parent_scope = scope;
4297
4298         environment_push(declaration);
4299         return append_declaration(declaration);
4300 }
4301
4302 static declaration_t *record_declaration(declaration_t *declaration)
4303 {
4304         return internal_record_declaration(declaration, false);
4305 }
4306
4307 static declaration_t *record_definition(declaration_t *declaration)
4308 {
4309         return internal_record_declaration(declaration, true);
4310 }
4311
4312 static void parser_error_multiple_definition(declaration_t *declaration,
4313                 const source_position_t *source_position)
4314 {
4315         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
4316                declaration->symbol, &declaration->source_position);
4317 }
4318
4319 static bool is_declaration_specifier(const token_t *token,
4320                                      bool only_specifiers_qualifiers)
4321 {
4322         switch(token->type) {
4323                 TYPE_SPECIFIERS
4324                 TYPE_QUALIFIERS
4325                         return true;
4326                 case T_IDENTIFIER:
4327                         return is_typedef_symbol(token->v.symbol);
4328
4329                 case T___extension__:
4330                 STORAGE_CLASSES
4331                         return !only_specifiers_qualifiers;
4332
4333                 default:
4334                         return false;
4335         }
4336 }
4337
4338 static void parse_init_declarator_rest(declaration_t *declaration)
4339 {
4340         eat('=');
4341
4342         type_t *orig_type = declaration->type;
4343         type_t *type      = skip_typeref(orig_type);
4344
4345         if (declaration->init.initializer != NULL) {
4346                 parser_error_multiple_definition(declaration, HERE);
4347         }
4348
4349         bool must_be_constant = false;
4350         if (declaration->storage_class == STORAGE_CLASS_STATIC
4351                         || declaration->storage_class == STORAGE_CLASS_THREAD_STATIC
4352                         || declaration->parent_scope == global_scope) {
4353                 must_be_constant = true;
4354         }
4355
4356         parse_initializer_env_t env;
4357         env.type             = orig_type;
4358         env.must_be_constant = must_be_constant;
4359         env.declaration      = declaration;
4360
4361         initializer_t *initializer = parse_initializer(&env);
4362
4363         if (env.type != orig_type) {
4364                 orig_type         = env.type;
4365                 type              = skip_typeref(orig_type);
4366                 declaration->type = env.type;
4367         }
4368
4369         if (is_type_function(type)) {
4370                 errorf(&declaration->source_position,
4371                        "initializers not allowed for function types at declator '%Y' (type '%T')",
4372                        declaration->symbol, orig_type);
4373         } else {
4374                 declaration->init.initializer = initializer;
4375         }
4376 }
4377
4378 /* parse rest of a declaration without any declarator */
4379 static void parse_anonymous_declaration_rest(
4380                 const declaration_specifiers_t *specifiers,
4381                 parsed_declaration_func finished_declaration)
4382 {
4383         eat(';');
4384
4385         declaration_t *const declaration    = allocate_declaration_zero();
4386         declaration->type                   = specifiers->type;
4387         declaration->declared_storage_class = specifiers->declared_storage_class;
4388         declaration->source_position        = specifiers->source_position;
4389         declaration->modifiers              = specifiers->modifiers;
4390
4391         if (declaration->declared_storage_class != STORAGE_CLASS_NONE) {
4392                 warningf(&declaration->source_position,
4393                          "useless storage class in empty declaration");
4394         }
4395         declaration->storage_class = STORAGE_CLASS_NONE;
4396
4397         type_t *type = declaration->type;
4398         switch (type->kind) {
4399                 case TYPE_COMPOUND_STRUCT:
4400                 case TYPE_COMPOUND_UNION: {
4401                         if (type->compound.declaration->symbol == NULL) {
4402                                 warningf(&declaration->source_position,
4403                                          "unnamed struct/union that defines no instances");
4404                         }
4405                         break;
4406                 }
4407
4408                 case TYPE_ENUM:
4409                         break;
4410
4411                 default:
4412                         warningf(&declaration->source_position, "empty declaration");
4413                         break;
4414         }
4415
4416         finished_declaration(declaration);
4417 }
4418
4419 static void parse_declaration_rest(declaration_t *ndeclaration,
4420                 const declaration_specifiers_t *specifiers,
4421                 parsed_declaration_func finished_declaration)
4422 {
4423         add_anchor_token(';');
4424         add_anchor_token('=');
4425         add_anchor_token(',');
4426         while(true) {
4427                 declaration_t *declaration = finished_declaration(ndeclaration);
4428
4429                 type_t *orig_type = declaration->type;
4430                 type_t *type      = skip_typeref(orig_type);
4431
4432                 if (type->kind != TYPE_FUNCTION &&
4433                     declaration->is_inline &&
4434                     is_type_valid(type)) {
4435                         warningf(&declaration->source_position,
4436                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
4437                 }
4438
4439                 if (token.type == '=') {
4440                         parse_init_declarator_rest(declaration);
4441                 }
4442
4443                 if (token.type != ',')
4444                         break;
4445                 eat(',');
4446
4447                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
4448         }
4449         expect(';');
4450
4451 end_error:
4452         rem_anchor_token(';');
4453         rem_anchor_token('=');
4454         rem_anchor_token(',');
4455 }
4456
4457 static declaration_t *finished_kr_declaration(declaration_t *declaration)
4458 {
4459         symbol_t *symbol  = declaration->symbol;
4460         if (symbol == NULL) {
4461                 errorf(HERE, "anonymous declaration not valid as function parameter");
4462                 return declaration;
4463         }
4464         namespace_t namespc = (namespace_t) declaration->namespc;
4465         if (namespc != NAMESPACE_NORMAL) {
4466                 return record_declaration(declaration);
4467         }
4468
4469         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4470         if (previous_declaration == NULL ||
4471                         previous_declaration->parent_scope != scope) {
4472                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4473                        symbol);
4474                 return declaration;
4475         }
4476
4477         if (previous_declaration->type == NULL) {
4478                 previous_declaration->type          = declaration->type;
4479                 previous_declaration->declared_storage_class = declaration->declared_storage_class;
4480                 previous_declaration->storage_class = declaration->storage_class;
4481                 previous_declaration->parent_scope  = scope;
4482                 return previous_declaration;
4483         } else {
4484                 return record_declaration(declaration);
4485         }
4486 }
4487
4488 static void parse_declaration(parsed_declaration_func finished_declaration)
4489 {
4490         declaration_specifiers_t specifiers;
4491         memset(&specifiers, 0, sizeof(specifiers));
4492         parse_declaration_specifiers(&specifiers);
4493
4494         if (token.type == ';') {
4495                 parse_anonymous_declaration_rest(&specifiers, append_declaration);
4496         } else {
4497                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
4498                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
4499         }
4500 }
4501
4502 static type_t *get_default_promoted_type(type_t *orig_type)
4503 {
4504         type_t *result = orig_type;
4505
4506         type_t *type = skip_typeref(orig_type);
4507         if (is_type_integer(type)) {
4508                 result = promote_integer(type);
4509         } else if (type == type_float) {
4510                 result = type_double;
4511         }
4512
4513         return result;
4514 }
4515
4516 static void parse_kr_declaration_list(declaration_t *declaration)
4517 {
4518         type_t *type = skip_typeref(declaration->type);
4519         if (!is_type_function(type))
4520                 return;
4521
4522         if (!type->function.kr_style_parameters)
4523                 return;
4524
4525         /* push function parameters */
4526         int       top        = environment_top();
4527         scope_t  *last_scope = scope;
4528         set_scope(&declaration->scope);
4529
4530         declaration_t *parameter = declaration->scope.declarations;
4531         for ( ; parameter != NULL; parameter = parameter->next) {
4532                 assert(parameter->parent_scope == NULL);
4533                 parameter->parent_scope = scope;
4534                 environment_push(parameter);
4535         }
4536
4537         /* parse declaration list */
4538         while (is_declaration_specifier(&token, false)) {
4539                 parse_declaration(finished_kr_declaration);
4540         }
4541
4542         /* pop function parameters */
4543         assert(scope == &declaration->scope);
4544         set_scope(last_scope);
4545         environment_pop_to(top);
4546
4547         /* update function type */
4548         type_t *new_type = duplicate_type(type);
4549
4550         function_parameter_t *parameters     = NULL;
4551         function_parameter_t *last_parameter = NULL;
4552
4553         declaration_t *parameter_declaration = declaration->scope.declarations;
4554         for( ; parameter_declaration != NULL;
4555                         parameter_declaration = parameter_declaration->next) {
4556                 type_t *parameter_type = parameter_declaration->type;
4557                 if (parameter_type == NULL) {
4558                         if (strict_mode) {
4559                                 errorf(HERE, "no type specified for function parameter '%Y'",
4560                                        parameter_declaration->symbol);
4561                         } else {
4562                                 if (warning.implicit_int) {
4563                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
4564                                                 parameter_declaration->symbol);
4565                                 }
4566                                 parameter_type              = type_int;
4567                                 parameter_declaration->type = parameter_type;
4568                         }
4569                 }
4570
4571                 semantic_parameter(parameter_declaration);
4572                 parameter_type = parameter_declaration->type;
4573
4574                 /*
4575                  * we need the default promoted types for the function type
4576                  */
4577                 parameter_type = get_default_promoted_type(parameter_type);
4578
4579                 function_parameter_t *function_parameter
4580                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
4581                 memset(function_parameter, 0, sizeof(function_parameter[0]));
4582
4583                 function_parameter->type = parameter_type;
4584                 if (last_parameter != NULL) {
4585                         last_parameter->next = function_parameter;
4586                 } else {
4587                         parameters = function_parameter;
4588                 }
4589                 last_parameter = function_parameter;
4590         }
4591
4592         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
4593          * prototype */
4594         new_type->function.parameters             = parameters;
4595         new_type->function.unspecified_parameters = true;
4596
4597         type = typehash_insert(new_type);
4598         if (type != new_type) {
4599                 obstack_free(type_obst, new_type);
4600         }
4601
4602         declaration->type = type;
4603 }
4604
4605 static bool first_err = true;
4606
4607 /**
4608  * When called with first_err set, prints the name of the current function,
4609  * else does noting.
4610  */
4611 static void print_in_function(void)
4612 {
4613         if (first_err) {
4614                 first_err = false;
4615                 diagnosticf("%s: In function '%Y':\n",
4616                         current_function->source_position.input_name,
4617                         current_function->symbol);
4618         }
4619 }
4620
4621 /**
4622  * Check if all labels are defined in the current function.
4623  * Check if all labels are used in the current function.
4624  */
4625 static void check_labels(void)
4626 {
4627         for (const goto_statement_t *goto_statement = goto_first;
4628             goto_statement != NULL;
4629             goto_statement = goto_statement->next) {
4630                 declaration_t *label = goto_statement->label;
4631
4632                 label->used = true;
4633                 if (label->source_position.input_name == NULL) {
4634                         print_in_function();
4635                         errorf(&goto_statement->base.source_position,
4636                                "label '%Y' used but not defined", label->symbol);
4637                  }
4638         }
4639         goto_first = goto_last = NULL;
4640
4641         if (warning.unused_label) {
4642                 for (const label_statement_t *label_statement = label_first;
4643                          label_statement != NULL;
4644                          label_statement = label_statement->next) {
4645                         const declaration_t *label = label_statement->label;
4646
4647                         if (! label->used) {
4648                                 print_in_function();
4649                                 warningf(&label_statement->base.source_position,
4650                                         "label '%Y' defined but not used", label->symbol);
4651                         }
4652                 }
4653         }
4654         label_first = label_last = NULL;
4655 }
4656
4657 /**
4658  * Check declarations of current_function for unused entities.
4659  */
4660 static void check_declarations(void)
4661 {
4662         if (warning.unused_parameter) {
4663                 const scope_t *scope = &current_function->scope;
4664
4665                 const declaration_t *parameter = scope->declarations;
4666                 for (; parameter != NULL; parameter = parameter->next) {
4667                         if (! parameter->used) {
4668                                 print_in_function();
4669                                 warningf(&parameter->source_position,
4670                                          "unused parameter '%Y'", parameter->symbol);
4671                         }
4672                 }
4673         }
4674         if (warning.unused_variable) {
4675         }
4676 }
4677
4678 static int determine_truth(expression_t const* const cond)
4679 {
4680         return
4681                 !is_constant_expression(cond) ? 0 :
4682                 fold_constant(cond) != 0      ? 1 :
4683                 -1;
4684 }
4685
4686 static bool noreturn_candidate;
4687
4688 static void check_reachable(statement_t *const stmt)
4689 {
4690         if (stmt->base.reachable)
4691                 return;
4692         if (stmt->kind != STATEMENT_DO_WHILE)
4693                 stmt->base.reachable = true;
4694
4695         statement_t *last = stmt;
4696         statement_t *next;
4697         switch (stmt->kind) {
4698                 case STATEMENT_INVALID:
4699                 case STATEMENT_EMPTY:
4700                 case STATEMENT_DECLARATION:
4701                 case STATEMENT_ASM:
4702                         next = stmt->base.next;
4703                         break;
4704
4705                 case STATEMENT_COMPOUND:
4706                         next = stmt->compound.statements;
4707                         break;
4708
4709                 case STATEMENT_RETURN:
4710                         noreturn_candidate = false;
4711                         return;
4712
4713                 case STATEMENT_IF: {
4714                         if_statement_t const* const ifs = &stmt->ifs;
4715                         int            const        val = determine_truth(ifs->condition);
4716
4717                         if (val >= 0)
4718                                 check_reachable(ifs->true_statement);
4719
4720                         if (val > 0)
4721                                 return;
4722
4723                         if (ifs->false_statement != NULL) {
4724                                 check_reachable(ifs->false_statement);
4725                                 return;
4726                         }
4727
4728                         next = stmt->base.next;
4729                         break;
4730                 }
4731
4732                 case STATEMENT_SWITCH: {
4733                         switch_statement_t const *const switchs = &stmt->switchs;
4734                         expression_t       const *const expr    = switchs->expression;
4735
4736                         if (is_constant_expression(expr)) {
4737                                 long                    const val      = fold_constant(expr);
4738                                 case_label_statement_t *      defaults = NULL;
4739                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4740                                         if (i->expression == NULL) {
4741                                                 defaults = i;
4742                                                 continue;
4743                                         }
4744
4745                                         expression_t *const case_expr = i->expression;
4746                                         if (is_constant_expression(case_expr) &&
4747                                             fold_constant(case_expr) == val) {
4748                                                 check_reachable((statement_t*)i);
4749                                                 return;
4750                                         }
4751                                 }
4752
4753                                 if (defaults != NULL) {
4754                                         check_reachable((statement_t*)defaults);
4755                                         return;
4756                                 }
4757                         } else {
4758                                 bool has_default = false;
4759                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4760                                         if (i->expression == NULL)
4761                                                 has_default = true;
4762
4763                                         check_reachable((statement_t*)i);
4764                                 }
4765
4766                                 if (has_default)
4767                                         return;
4768                         }
4769
4770                         next = stmt->base.next;
4771                         break;
4772                 }
4773
4774                 case STATEMENT_EXPRESSION: {
4775                         /* Check for noreturn function call */
4776                         expression_t const *const expr = stmt->expression.expression;
4777                         if (expr->kind == EXPR_CALL) {
4778                                 expression_t const *const func = expr->call.function;
4779                                 if (func->kind == EXPR_REFERENCE) {
4780                                         declaration_t const *const decl = func->reference.declaration;
4781                                         if (decl != NULL && decl->modifiers & DM_NORETURN) {
4782                                                 return;
4783                                         }
4784                                 }
4785                         }
4786
4787                         next = stmt->base.next;
4788                         break;
4789                 }
4790
4791                 case STATEMENT_CONTINUE: {
4792                         statement_t *parent = stmt;
4793                         for (;;) {
4794                                 parent = parent->base.parent;
4795                                 if (parent == NULL) /* continue not within loop */
4796                                         return;
4797
4798                                 next = parent;
4799                                 switch (parent->kind) {
4800                                         case STATEMENT_WHILE:    goto continue_while;
4801                                         case STATEMENT_DO_WHILE: goto continue_do_while;
4802                                         case STATEMENT_FOR:      goto continue_for;
4803
4804                                         default: break;
4805                                 }
4806                         }
4807                 }
4808
4809                 case STATEMENT_BREAK: {
4810                         statement_t *parent = stmt;
4811                         for (;;) {
4812                                 parent = parent->base.parent;
4813                                 if (parent == NULL) /* break not within loop/switch */
4814                                         return;
4815
4816                                 switch (parent->kind) {
4817                                         case STATEMENT_SWITCH:
4818                                         case STATEMENT_WHILE:
4819                                         case STATEMENT_DO_WHILE:
4820                                         case STATEMENT_FOR:
4821                                                 last = parent;
4822                                                 next = parent->base.next;
4823                                                 goto found_break_parent;
4824
4825                                         default: break;
4826                                 }
4827                         }
4828 found_break_parent:
4829                         break;
4830                 }
4831
4832                 case STATEMENT_GOTO:
4833                         next = stmt->gotos.label->init.statement;
4834                         if (next == NULL) /* missing label */
4835                                 return;
4836                         break;
4837
4838                 case STATEMENT_LABEL:
4839                         next = stmt->label.statement;
4840                         break;
4841
4842                 case STATEMENT_CASE_LABEL:
4843                         next = stmt->case_label.statement;
4844                         break;
4845
4846                 case STATEMENT_WHILE: {
4847                         while_statement_t const *const whiles = &stmt->whiles;
4848                         int                      const val    = determine_truth(whiles->condition);
4849
4850                         if (val >= 0)
4851                                 check_reachable(whiles->body);
4852
4853                         if (val > 0)
4854                                 return;
4855
4856                         next = stmt->base.next;
4857                         break;
4858                 }
4859
4860                 case STATEMENT_DO_WHILE:
4861                         next = stmt->do_while.body;
4862                         break;
4863
4864                 case STATEMENT_FOR: {
4865                         for_statement_t *const fors = &stmt->fors;
4866
4867                         if (fors->condition_reachable)
4868                                 return;
4869                         fors->condition_reachable = true;
4870
4871                         expression_t const *const cond = fors->condition;
4872                         int          const        val  =
4873                                 cond == NULL ? 1 : determine_truth(cond);
4874
4875                         if (val >= 0)
4876                                 check_reachable(fors->body);
4877
4878                         if (val > 0)
4879                                 return;
4880
4881                         next = stmt->base.next;
4882                         break;
4883                 }
4884
4885                 case STATEMENT_MS_TRY:
4886                 case STATEMENT_LEAVE:
4887                         panic("unimplemented");
4888         }
4889
4890         while (next == NULL) {
4891                 next = last->base.parent;
4892                 if (next == NULL) {
4893                         noreturn_candidate = false;
4894
4895                         type_t *const type = current_function->type;
4896                         assert(is_type_function(type));
4897                         type_t *const ret  = skip_typeref(type->function.return_type);
4898                         if (warning.return_type                    &&
4899                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
4900                             !is_sym_main(current_function->symbol)) {
4901                                 warningf(&stmt->base.source_position,
4902                                          "control reaches end of non-void function");
4903                         }
4904                         return;
4905                 }
4906
4907                 switch (next->kind) {
4908                         case STATEMENT_INVALID:
4909                         case STATEMENT_EMPTY:
4910                         case STATEMENT_DECLARATION:
4911                         case STATEMENT_EXPRESSION:
4912                         case STATEMENT_ASM:
4913                         case STATEMENT_RETURN:
4914                         case STATEMENT_CONTINUE:
4915                         case STATEMENT_BREAK:
4916                         case STATEMENT_GOTO:
4917                         case STATEMENT_LEAVE:
4918                                 panic("invalid control flow in function");
4919
4920                         case STATEMENT_COMPOUND:
4921                         case STATEMENT_IF:
4922                         case STATEMENT_SWITCH:
4923                         case STATEMENT_LABEL:
4924                         case STATEMENT_CASE_LABEL:
4925                                 last = next;
4926                                 next = next->base.next;
4927                                 break;
4928
4929                         case STATEMENT_WHILE: {
4930 continue_while:
4931                                 if (next->base.reachable)
4932                                         return;
4933                                 next->base.reachable = true;
4934
4935                                 while_statement_t const *const whiles = &next->whiles;
4936                                 int                      const val    = determine_truth(whiles->condition);
4937
4938                                 if (val >= 0)
4939                                         check_reachable(whiles->body);
4940
4941                                 if (val > 0)
4942                                         return;
4943
4944                                 last = next;
4945                                 next = next->base.next;
4946                                 break;
4947                         }
4948
4949                         case STATEMENT_DO_WHILE: {
4950 continue_do_while:
4951                                 if (next->base.reachable)
4952                                         return;
4953                                 next->base.reachable = true;
4954
4955                                 do_while_statement_t const *const dw  = &next->do_while;
4956                                 int                  const        val = determine_truth(dw->condition);
4957
4958                                 if (val >= 0)
4959                                         check_reachable(dw->body);
4960
4961                                 if (val > 0)
4962                                         return;
4963
4964                                 last = next;
4965                                 next = next->base.next;
4966                                 break;
4967                         }
4968
4969                         case STATEMENT_FOR: {
4970 continue_for:;
4971                                 for_statement_t *const fors = &next->fors;
4972
4973                                 fors->step_reachable = true;
4974
4975                                 if (fors->condition_reachable)
4976                                         return;
4977                                 fors->condition_reachable = true;
4978
4979                                 expression_t const *const cond = fors->condition;
4980                                 int          const        val  =
4981                                         cond == NULL ? 1 : determine_truth(cond);
4982
4983                                 if (val >= 0)
4984                                         check_reachable(fors->body);
4985
4986                                 if (val > 0)
4987                                         return;
4988
4989                                 last = next;
4990                                 next = next->base.next;
4991                                 break;
4992                         }
4993
4994                         case STATEMENT_MS_TRY:
4995                                 panic("unimplemented");
4996                 }
4997         }
4998
4999         if (next == NULL) {
5000                 next = stmt->base.parent;
5001                 if (next == NULL) {
5002                         warningf(&stmt->base.source_position,
5003                                  "control reaches end of non-void function");
5004                 }
5005         }
5006
5007         check_reachable(next);
5008 }
5009
5010 static void check_unreachable(statement_t const* const stmt)
5011 {
5012         if (!stmt->base.reachable            &&
5013             stmt->kind != STATEMENT_COMPOUND &&
5014             stmt->kind != STATEMENT_DO_WHILE &&
5015             stmt->kind != STATEMENT_FOR) {
5016                 warningf(&stmt->base.source_position, "statement is unreachable");
5017         }
5018
5019         switch (stmt->kind) {
5020                 case STATEMENT_INVALID:
5021                 case STATEMENT_EMPTY:
5022                 case STATEMENT_RETURN:
5023                 case STATEMENT_DECLARATION:
5024                 case STATEMENT_EXPRESSION:
5025                 case STATEMENT_CONTINUE:
5026                 case STATEMENT_BREAK:
5027                 case STATEMENT_GOTO:
5028                 case STATEMENT_ASM:
5029                 case STATEMENT_LEAVE:
5030                         break;
5031
5032                 case STATEMENT_COMPOUND:
5033                         if (stmt->compound.statements)
5034                                 check_unreachable(stmt->compound.statements);
5035                         break;
5036
5037                 case STATEMENT_IF:
5038                         check_unreachable(stmt->ifs.true_statement);
5039                         if (stmt->ifs.false_statement != NULL)
5040                                 check_unreachable(stmt->ifs.false_statement);
5041                         break;
5042
5043                 case STATEMENT_SWITCH:
5044                         check_unreachable(stmt->switchs.body);
5045                         break;
5046
5047                 case STATEMENT_LABEL:
5048                         check_unreachable(stmt->label.statement);
5049                         break;
5050
5051                 case STATEMENT_CASE_LABEL:
5052                         check_unreachable(stmt->case_label.statement);
5053                         break;
5054
5055                 case STATEMENT_WHILE:
5056                         check_unreachable(stmt->whiles.body);
5057                         break;
5058
5059                 case STATEMENT_DO_WHILE:
5060                         check_unreachable(stmt->do_while.body);
5061                         if (!stmt->base.reachable) {
5062                                 expression_t const *const cond = stmt->do_while.condition;
5063                                 if (determine_truth(cond) >= 0) {
5064                                         warningf(&cond->base.source_position,
5065                                                  "condition of do-while-loop is unreachable");
5066                                 }
5067                         }
5068                         break;
5069
5070                 case STATEMENT_FOR: {
5071                         for_statement_t const* const fors = &stmt->fors;
5072
5073                         // if init and step are unreachable, cond is unreachable, too
5074                         if (!stmt->base.reachable && !fors->step_reachable) {
5075                                 warningf(&stmt->base.source_position, "statement is unreachable");
5076                         } else {
5077                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5078                                         warningf(&fors->initialisation->base.source_position,
5079                                                  "initialisation of for-statement is unreachable");
5080                                 }
5081
5082                                 if (!fors->condition_reachable && fors->condition != NULL) {
5083                                         warningf(&fors->condition->base.source_position,
5084                                                  "condition of for-statement is unreachable");
5085                                 }
5086
5087                                 if (!fors->step_reachable && fors->step != NULL) {
5088                                         warningf(&fors->step->base.source_position,
5089                                                  "step of for-statement is unreachable");
5090                                 }
5091                         }
5092
5093                         check_unreachable(stmt->fors.body);
5094                         break;
5095                 }
5096
5097                 case STATEMENT_MS_TRY:
5098                         panic("unimplemented");
5099         }
5100
5101         if (stmt->base.next)
5102                 check_unreachable(stmt->base.next);
5103 }
5104
5105 static void parse_external_declaration(void)
5106 {
5107         /* function-definitions and declarations both start with declaration
5108          * specifiers */
5109         declaration_specifiers_t specifiers;
5110         memset(&specifiers, 0, sizeof(specifiers));
5111
5112         add_anchor_token(';');
5113         parse_declaration_specifiers(&specifiers);
5114         rem_anchor_token(';');
5115
5116         /* must be a declaration */
5117         if (token.type == ';') {
5118                 parse_anonymous_declaration_rest(&specifiers, append_declaration);
5119                 return;
5120         }
5121
5122         add_anchor_token(',');
5123         add_anchor_token('=');
5124         rem_anchor_token(';');
5125
5126         /* declarator is common to both function-definitions and declarations */
5127         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5128
5129         rem_anchor_token(',');
5130         rem_anchor_token('=');
5131         rem_anchor_token(';');
5132
5133         /* must be a declaration */
5134         switch (token.type) {
5135                 case ',':
5136                 case ';':
5137                         parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
5138                         return;
5139
5140                 case '=':
5141                         parse_declaration_rest(ndeclaration, &specifiers, record_definition);
5142                         return;
5143         }
5144
5145         /* must be a function definition */
5146         parse_kr_declaration_list(ndeclaration);
5147
5148         if (token.type != '{') {
5149                 parse_error_expected("while parsing function definition", '{', NULL);
5150                 eat_until_matching_token(';');
5151                 return;
5152         }
5153
5154         type_t *type = ndeclaration->type;
5155
5156         /* note that we don't skip typerefs: the standard doesn't allow them here
5157          * (so we can't use is_type_function here) */
5158         if (type->kind != TYPE_FUNCTION) {
5159                 if (is_type_valid(type)) {
5160                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5161                                type, ndeclaration->symbol);
5162                 }
5163                 eat_block();
5164                 return;
5165         }
5166
5167         /* § 6.7.5.3 (14) a function definition with () means no
5168          * parameters (and not unspecified parameters) */
5169         if (type->function.unspecified_parameters
5170                         && type->function.parameters == NULL
5171                         && !type->function.kr_style_parameters) {
5172                 type_t *duplicate = duplicate_type(type);
5173                 duplicate->function.unspecified_parameters = false;
5174
5175                 type = typehash_insert(duplicate);
5176                 if (type != duplicate) {
5177                         obstack_free(type_obst, duplicate);
5178                 }
5179                 ndeclaration->type = type;
5180         }
5181
5182         declaration_t *const declaration = record_definition(ndeclaration);
5183         if (ndeclaration != declaration) {
5184                 declaration->scope = ndeclaration->scope;
5185         }
5186         type = skip_typeref(declaration->type);
5187
5188         /* push function parameters and switch scope */
5189         int       top        = environment_top();
5190         scope_t  *last_scope = scope;
5191         set_scope(&declaration->scope);
5192
5193         declaration_t *parameter = declaration->scope.declarations;
5194         for( ; parameter != NULL; parameter = parameter->next) {
5195                 if (parameter->parent_scope == &ndeclaration->scope) {
5196                         parameter->parent_scope = scope;
5197                 }
5198                 assert(parameter->parent_scope == NULL
5199                                 || parameter->parent_scope == scope);
5200                 parameter->parent_scope = scope;
5201                 if (parameter->symbol == NULL) {
5202                         errorf(&ndeclaration->source_position, "parameter name omitted");
5203                         continue;
5204                 }
5205                 environment_push(parameter);
5206         }
5207
5208         if (declaration->init.statement != NULL) {
5209                 parser_error_multiple_definition(declaration, HERE);
5210                 eat_block();
5211         } else {
5212                 /* parse function body */
5213                 int            label_stack_top      = label_top();
5214                 declaration_t *old_current_function = current_function;
5215                 current_function                    = declaration;
5216                 current_parent                      = NULL;
5217
5218                 statement_t *const body = parse_compound_statement(false);
5219                 declaration->init.statement = body;
5220                 first_err = true;
5221                 check_labels();
5222                 check_declarations();
5223                 if (warning.return_type      ||
5224                     warning.unreachable_code ||
5225                     (warning.missing_noreturn && !(declaration->modifiers & DM_NORETURN))) {
5226                         noreturn_candidate = true;
5227                         check_reachable(body);
5228                         if (warning.unreachable_code)
5229                                 check_unreachable(body);
5230                         if (warning.missing_noreturn &&
5231                             noreturn_candidate       &&
5232                             !(declaration->modifiers & DM_NORETURN)) {
5233                                 warningf(&body->base.source_position,
5234                                          "function '%#T' is candidate for attribute 'noreturn'",
5235                                          type, declaration->symbol);
5236                         }
5237                 }
5238
5239                 assert(current_parent   == NULL);
5240                 assert(current_function == declaration);
5241                 current_function = old_current_function;
5242                 label_pop_to(label_stack_top);
5243         }
5244
5245         assert(scope == &declaration->scope);
5246         set_scope(last_scope);
5247         environment_pop_to(top);
5248 }
5249
5250 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5251                                   source_position_t *source_position)
5252 {
5253         type_t *type = allocate_type_zero(TYPE_BITFIELD, source_position);
5254
5255         type->bitfield.base_type = base_type;
5256         type->bitfield.size      = size;
5257
5258         return type;
5259 }
5260
5261 static declaration_t *find_compound_entry(declaration_t *compound_declaration,
5262                                           symbol_t *symbol)
5263 {
5264         declaration_t *iter = compound_declaration->scope.declarations;
5265         for( ; iter != NULL; iter = iter->next) {
5266                 if (iter->namespc != NAMESPACE_NORMAL)
5267                         continue;
5268
5269                 if (iter->symbol == NULL) {
5270                         type_t *type = skip_typeref(iter->type);
5271                         if (is_type_compound(type)) {
5272                                 declaration_t *result
5273                                         = find_compound_entry(type->compound.declaration, symbol);
5274                                 if (result != NULL)
5275                                         return result;
5276                         }
5277                         continue;
5278                 }
5279
5280                 if (iter->symbol == symbol) {
5281                         return iter;
5282                 }
5283         }
5284
5285         return NULL;
5286 }
5287
5288 static void parse_compound_declarators(declaration_t *struct_declaration,
5289                 const declaration_specifiers_t *specifiers)
5290 {
5291         declaration_t *last_declaration = struct_declaration->scope.declarations;
5292         if (last_declaration != NULL) {
5293                 while(last_declaration->next != NULL) {
5294                         last_declaration = last_declaration->next;
5295                 }
5296         }
5297
5298         while(1) {
5299                 declaration_t *declaration;
5300
5301                 if (token.type == ':') {
5302                         source_position_t source_position = *HERE;
5303                         next_token();
5304
5305                         type_t *base_type = specifiers->type;
5306                         expression_t *size = parse_constant_expression();
5307
5308                         if (!is_type_integer(skip_typeref(base_type))) {
5309                                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5310                                        base_type);
5311                         }
5312
5313                         type_t *type = make_bitfield_type(base_type, size, &source_position);
5314
5315                         declaration                         = allocate_declaration_zero();
5316                         declaration->namespc                = NAMESPACE_NORMAL;
5317                         declaration->declared_storage_class = STORAGE_CLASS_NONE;
5318                         declaration->storage_class          = STORAGE_CLASS_NONE;
5319                         declaration->source_position        = source_position;
5320                         declaration->modifiers              = specifiers->modifiers;
5321                         declaration->type                   = type;
5322                 } else {
5323                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
5324
5325                         type_t *orig_type = declaration->type;
5326                         type_t *type      = skip_typeref(orig_type);
5327
5328                         if (token.type == ':') {
5329                                 source_position_t source_position = *HERE;
5330                                 next_token();
5331                                 expression_t *size = parse_constant_expression();
5332
5333                                 if (!is_type_integer(type)) {
5334                                         errorf(HERE, "bitfield base type '%T' is not an "
5335                                                "integer type", orig_type);
5336                                 }
5337
5338                                 type_t *bitfield_type = make_bitfield_type(orig_type, size, &source_position);
5339                                 declaration->type = bitfield_type;
5340                         } else {
5341                                 /* TODO we ignore arrays for now... what is missing is a check
5342                                  * that they're at the end of the struct */
5343                                 if (is_type_incomplete(type) && !is_type_array(type)) {
5344                                         errorf(HERE,
5345                                                "compound member '%Y' has incomplete type '%T'",
5346                                                declaration->symbol, orig_type);
5347                                 } else if (is_type_function(type)) {
5348                                         errorf(HERE, "compound member '%Y' must not have function "
5349                                                "type '%T'", declaration->symbol, orig_type);
5350                                 }
5351                         }
5352                 }
5353
5354                 /* make sure we don't define a symbol multiple times */
5355                 symbol_t *symbol = declaration->symbol;
5356                 if (symbol != NULL) {
5357                         declaration_t *prev_decl
5358                                 = find_compound_entry(struct_declaration, symbol);
5359
5360                         if (prev_decl != NULL) {
5361                                 assert(prev_decl->symbol == symbol);
5362                                 errorf(&declaration->source_position,
5363                                        "multiple declarations of symbol '%Y' (declared %P)",
5364                                        symbol, &prev_decl->source_position);
5365                         }
5366                 }
5367
5368                 /* append declaration */
5369                 if (last_declaration != NULL) {
5370                         last_declaration->next = declaration;
5371                 } else {
5372                         struct_declaration->scope.declarations = declaration;
5373                 }
5374                 last_declaration = declaration;
5375
5376                 if (token.type != ',')
5377                         break;
5378                 next_token();
5379         }
5380         expect(';');
5381
5382 end_error:
5383         ;
5384 }
5385
5386 static void parse_compound_type_entries(declaration_t *compound_declaration)
5387 {
5388         eat('{');
5389         add_anchor_token('}');
5390
5391         while(token.type != '}' && token.type != T_EOF) {
5392                 declaration_specifiers_t specifiers;
5393                 memset(&specifiers, 0, sizeof(specifiers));
5394                 parse_declaration_specifiers(&specifiers);
5395
5396                 parse_compound_declarators(compound_declaration, &specifiers);
5397         }
5398         rem_anchor_token('}');
5399
5400         if (token.type == T_EOF) {
5401                 errorf(HERE, "EOF while parsing struct");
5402         }
5403         next_token();
5404 }
5405
5406 static type_t *parse_typename(void)
5407 {
5408         declaration_specifiers_t specifiers;
5409         memset(&specifiers, 0, sizeof(specifiers));
5410         parse_declaration_specifiers(&specifiers);
5411         if (specifiers.declared_storage_class != STORAGE_CLASS_NONE) {
5412                 /* TODO: improve error message, user does probably not know what a
5413                  * storage class is...
5414                  */
5415                 errorf(HERE, "typename may not have a storage class");
5416         }
5417
5418         type_t *result = parse_abstract_declarator(specifiers.type);
5419
5420         return result;
5421 }
5422
5423
5424
5425
5426 typedef expression_t* (*parse_expression_function) (unsigned precedence);
5427 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
5428                                                           expression_t *left);
5429
5430 typedef struct expression_parser_function_t expression_parser_function_t;
5431 struct expression_parser_function_t {
5432         unsigned                         precedence;
5433         parse_expression_function        parser;
5434         unsigned                         infix_precedence;
5435         parse_expression_infix_function  infix_parser;
5436 };
5437
5438 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5439
5440 /**
5441  * Prints an error message if an expression was expected but not read
5442  */
5443 static expression_t *expected_expression_error(void)
5444 {
5445         /* skip the error message if the error token was read */
5446         if (token.type != T_ERROR) {
5447                 errorf(HERE, "expected expression, got token '%K'", &token);
5448         }
5449         next_token();
5450
5451         return create_invalid_expression();
5452 }
5453
5454 /**
5455  * Parse a string constant.
5456  */
5457 static expression_t *parse_string_const(void)
5458 {
5459         wide_string_t wres;
5460         if (token.type == T_STRING_LITERAL) {
5461                 string_t res = token.v.string;
5462                 next_token();
5463                 while (token.type == T_STRING_LITERAL) {
5464                         res = concat_strings(&res, &token.v.string);
5465                         next_token();
5466                 }
5467                 if (token.type != T_WIDE_STRING_LITERAL) {
5468                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
5469                         /* note: that we use type_char_ptr here, which is already the
5470                          * automatic converted type. revert_automatic_type_conversion
5471                          * will construct the array type */
5472                         cnst->base.type    = type_char_ptr;
5473                         cnst->string.value = res;
5474                         return cnst;
5475                 }
5476
5477                 wres = concat_string_wide_string(&res, &token.v.wide_string);
5478         } else {
5479                 wres = token.v.wide_string;
5480         }
5481         next_token();
5482
5483         for (;;) {
5484                 switch (token.type) {
5485                         case T_WIDE_STRING_LITERAL:
5486                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
5487                                 break;
5488
5489                         case T_STRING_LITERAL:
5490                                 wres = concat_wide_string_string(&wres, &token.v.string);
5491                                 break;
5492
5493                         default: {
5494                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
5495                                 cnst->base.type         = type_wchar_t_ptr;
5496                                 cnst->wide_string.value = wres;
5497                                 return cnst;
5498                         }
5499                 }
5500                 next_token();
5501         }
5502 }
5503
5504 /**
5505  * Parse an integer constant.
5506  */
5507 static expression_t *parse_int_const(void)
5508 {
5509         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5510         cnst->base.source_position = *HERE;
5511         cnst->base.type            = token.datatype;
5512         cnst->conste.v.int_value   = token.v.intvalue;
5513
5514         next_token();
5515
5516         return cnst;
5517 }
5518
5519 /**
5520  * Parse a character constant.
5521  */
5522 static expression_t *parse_character_constant(void)
5523 {
5524         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
5525
5526         cnst->base.source_position = *HERE;
5527         cnst->base.type            = token.datatype;
5528         cnst->conste.v.character   = token.v.string;
5529
5530         if (cnst->conste.v.character.size != 1) {
5531                 if (warning.multichar && (c_mode & _GNUC)) {
5532                         /* TODO */
5533                         warningf(HERE, "multi-character character constant");
5534                 } else {
5535                         errorf(HERE, "more than 1 characters in character constant");
5536                 }
5537         }
5538         next_token();
5539
5540         return cnst;
5541 }
5542
5543 /**
5544  * Parse a wide character constant.
5545  */
5546 static expression_t *parse_wide_character_constant(void)
5547 {
5548         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
5549
5550         cnst->base.source_position    = *HERE;
5551         cnst->base.type               = token.datatype;
5552         cnst->conste.v.wide_character = token.v.wide_string;
5553
5554         if (cnst->conste.v.wide_character.size != 1) {
5555                 if (warning.multichar && (c_mode & _GNUC)) {
5556                         /* TODO */
5557                         warningf(HERE, "multi-character character constant");
5558                 } else {
5559                         errorf(HERE, "more than 1 characters in character constant");
5560                 }
5561         }
5562         next_token();
5563
5564         return cnst;
5565 }
5566
5567 /**
5568  * Parse a float constant.
5569  */
5570 static expression_t *parse_float_const(void)
5571 {
5572         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5573         cnst->base.type            = token.datatype;
5574         cnst->conste.v.float_value = token.v.floatvalue;
5575
5576         next_token();
5577
5578         return cnst;
5579 }
5580
5581 static declaration_t *create_implicit_function(symbol_t *symbol,
5582                 const source_position_t *source_position)
5583 {
5584         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION, source_position);
5585         ntype->function.return_type            = type_int;
5586         ntype->function.unspecified_parameters = true;
5587
5588         type_t *type = typehash_insert(ntype);
5589         if (type != ntype) {
5590                 free_type(ntype);
5591         }
5592
5593         declaration_t *const declaration    = allocate_declaration_zero();
5594         declaration->storage_class          = STORAGE_CLASS_EXTERN;
5595         declaration->declared_storage_class = STORAGE_CLASS_EXTERN;
5596         declaration->type                   = type;
5597         declaration->symbol                 = symbol;
5598         declaration->source_position        = *source_position;
5599
5600         bool strict_prototypes_old = warning.strict_prototypes;
5601         warning.strict_prototypes  = false;
5602         record_declaration(declaration);
5603         warning.strict_prototypes = strict_prototypes_old;
5604
5605         return declaration;
5606 }
5607
5608 /**
5609  * Creates a return_type (func)(argument_type) function type if not
5610  * already exists.
5611  */
5612 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
5613                                     type_t *argument_type2)
5614 {
5615         function_parameter_t *parameter2
5616                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
5617         memset(parameter2, 0, sizeof(parameter2[0]));
5618         parameter2->type = argument_type2;
5619
5620         function_parameter_t *parameter1
5621                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
5622         memset(parameter1, 0, sizeof(parameter1[0]));
5623         parameter1->type = argument_type1;
5624         parameter1->next = parameter2;
5625
5626         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5627         type->function.return_type = return_type;
5628         type->function.parameters  = parameter1;
5629
5630         type_t *result = typehash_insert(type);
5631         if (result != type) {
5632                 free_type(type);
5633         }
5634
5635         return result;
5636 }
5637
5638 /**
5639  * Creates a return_type (func)(argument_type) function type if not
5640  * already exists.
5641  *
5642  * @param return_type    the return type
5643  * @param argument_type  the argument type
5644  */
5645 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
5646 {
5647         function_parameter_t *parameter
5648                 = obstack_alloc(type_obst, sizeof(parameter[0]));
5649         memset(parameter, 0, sizeof(parameter[0]));
5650         parameter->type = argument_type;
5651
5652         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5653         type->function.return_type = return_type;
5654         type->function.parameters  = parameter;
5655
5656         type_t *result = typehash_insert(type);
5657         if (result != type) {
5658                 free_type(type);
5659         }
5660
5661         return result;
5662 }
5663
5664 static type_t *make_function_0_type(type_t *return_type)
5665 {
5666         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5667         type->function.return_type = return_type;
5668         type->function.parameters  = NULL;
5669
5670         type_t *result = typehash_insert(type);
5671         if (result != type) {
5672                 free_type(type);
5673         }
5674
5675         return result;
5676 }
5677
5678 /**
5679  * Creates a function type for some function like builtins.
5680  *
5681  * @param symbol   the symbol describing the builtin
5682  */
5683 static type_t *get_builtin_symbol_type(symbol_t *symbol)
5684 {
5685         switch(symbol->ID) {
5686         case T___builtin_alloca:
5687                 return make_function_1_type(type_void_ptr, type_size_t);
5688         case T___builtin_huge_val:
5689                 return make_function_0_type(type_double);
5690         case T___builtin_nan:
5691                 return make_function_1_type(type_double, type_char_ptr);
5692         case T___builtin_nanf:
5693                 return make_function_1_type(type_float, type_char_ptr);
5694         case T___builtin_nand:
5695                 return make_function_1_type(type_long_double, type_char_ptr);
5696         case T___builtin_va_end:
5697                 return make_function_1_type(type_void, type_valist);
5698         case T___builtin_expect:
5699                 return make_function_2_type(type_long, type_long, type_long);
5700         default:
5701                 internal_errorf(HERE, "not implemented builtin symbol found");
5702         }
5703 }
5704
5705 /**
5706  * Performs automatic type cast as described in § 6.3.2.1.
5707  *
5708  * @param orig_type  the original type
5709  */
5710 static type_t *automatic_type_conversion(type_t *orig_type)
5711 {
5712         type_t *type = skip_typeref(orig_type);
5713         if (is_type_array(type)) {
5714                 array_type_t *array_type   = &type->array;
5715                 type_t       *element_type = array_type->element_type;
5716                 unsigned      qualifiers   = array_type->base.qualifiers;
5717
5718                 return make_pointer_type(element_type, qualifiers);
5719         }
5720
5721         if (is_type_function(type)) {
5722                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
5723         }
5724
5725         return orig_type;
5726 }
5727
5728 /**
5729  * reverts the automatic casts of array to pointer types and function
5730  * to function-pointer types as defined § 6.3.2.1
5731  */
5732 type_t *revert_automatic_type_conversion(const expression_t *expression)
5733 {
5734         switch (expression->kind) {
5735                 case EXPR_REFERENCE: return expression->reference.declaration->type;
5736                 case EXPR_SELECT:    return expression->select.compound_entry->type;
5737
5738                 case EXPR_UNARY_DEREFERENCE: {
5739                         const expression_t *const value = expression->unary.value;
5740                         type_t             *const type  = skip_typeref(value->base.type);
5741                         assert(is_type_pointer(type));
5742                         return type->pointer.points_to;
5743                 }
5744
5745                 case EXPR_BUILTIN_SYMBOL:
5746                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
5747
5748                 case EXPR_ARRAY_ACCESS: {
5749                         const expression_t *array_ref = expression->array_access.array_ref;
5750                         type_t             *type_left = skip_typeref(array_ref->base.type);
5751                         if (!is_type_valid(type_left))
5752                                 return type_left;
5753                         assert(is_type_pointer(type_left));
5754                         return type_left->pointer.points_to;
5755                 }
5756
5757                 case EXPR_STRING_LITERAL: {
5758                         size_t size = expression->string.value.size;
5759                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
5760                 }
5761
5762                 case EXPR_WIDE_STRING_LITERAL: {
5763                         size_t size = expression->wide_string.value.size;
5764                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
5765                 }
5766
5767                 case EXPR_COMPOUND_LITERAL:
5768                         return expression->compound_literal.type;
5769
5770                 default: break;
5771         }
5772
5773         return expression->base.type;
5774 }
5775
5776 static expression_t *parse_reference(void)
5777 {
5778         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
5779
5780         reference_expression_t *ref = &expression->reference;
5781         symbol_t *const symbol = token.v.symbol;
5782
5783         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
5784
5785         source_position_t source_position = token.source_position;
5786         next_token();
5787
5788         if (declaration == NULL) {
5789                 if (! strict_mode && token.type == '(') {
5790                         /* an implicitly defined function */
5791                         if (warning.implicit_function_declaration) {
5792                                 warningf(HERE, "implicit declaration of function '%Y'",
5793                                         symbol);
5794                         }
5795
5796                         declaration = create_implicit_function(symbol,
5797                                                                &source_position);
5798                 } else {
5799                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
5800                         return create_invalid_expression();
5801                 }
5802         }
5803
5804         type_t *type         = declaration->type;
5805
5806         /* we always do the auto-type conversions; the & and sizeof parser contains
5807          * code to revert this! */
5808         type = automatic_type_conversion(type);
5809
5810         ref->declaration = declaration;
5811         ref->base.type   = type;
5812
5813         /* this declaration is used */
5814         declaration->used = true;
5815
5816         /* check for deprecated functions */
5817         if (warning.deprecated_declarations &&
5818             declaration->modifiers & DM_DEPRECATED) {
5819                 char const *const prefix = is_type_function(declaration->type) ?
5820                         "function" : "variable";
5821
5822                 if (declaration->deprecated_string != NULL) {
5823                         warningf(&source_position,
5824                                 "%s '%Y' is deprecated (declared %P): \"%s\"", prefix,
5825                                 declaration->symbol, &declaration->source_position,
5826                                 declaration->deprecated_string);
5827                 } else {
5828                         warningf(&source_position,
5829                                 "%s '%Y' is deprecated (declared %P)", prefix,
5830                                 declaration->symbol, &declaration->source_position);
5831                 }
5832         }
5833
5834         return expression;
5835 }
5836
5837 static void check_cast_allowed(expression_t *expression, type_t *dest_type)
5838 {
5839         (void) expression;
5840         (void) dest_type;
5841         /* TODO check if explicit cast is allowed and issue warnings/errors */
5842 }
5843
5844 static expression_t *parse_compound_literal(type_t *type)
5845 {
5846         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
5847
5848         parse_initializer_env_t env;
5849         env.type             = type;
5850         env.declaration      = NULL;
5851         env.must_be_constant = false;
5852         initializer_t *initializer = parse_initializer(&env);
5853         type = env.type;
5854
5855         expression->compound_literal.initializer = initializer;
5856         expression->compound_literal.type        = type;
5857         expression->base.type                    = automatic_type_conversion(type);
5858
5859         return expression;
5860 }
5861
5862 /**
5863  * Parse a cast expression.
5864  */
5865 static expression_t *parse_cast(void)
5866 {
5867         source_position_t source_position = token.source_position;
5868
5869         type_t *type  = parse_typename();
5870
5871         /* matching add_anchor_token() is at call site */
5872         rem_anchor_token(')');
5873         expect(')');
5874
5875         if (token.type == '{') {
5876                 return parse_compound_literal(type);
5877         }
5878
5879         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
5880         cast->base.source_position = source_position;
5881
5882         expression_t *value = parse_sub_expression(20);
5883
5884         check_cast_allowed(value, type);
5885
5886         cast->base.type   = type;
5887         cast->unary.value = value;
5888
5889         return cast;
5890 end_error:
5891         return create_invalid_expression();
5892 }
5893
5894 /**
5895  * Parse a statement expression.
5896  */
5897 static expression_t *parse_statement_expression(void)
5898 {
5899         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
5900
5901         statement_t *statement           = parse_compound_statement(true);
5902         expression->statement.statement  = statement;
5903         expression->base.source_position = statement->base.source_position;
5904
5905         /* find last statement and use its type */
5906         type_t *type = type_void;
5907         const statement_t *stmt = statement->compound.statements;
5908         if (stmt != NULL) {
5909                 while (stmt->base.next != NULL)
5910                         stmt = stmt->base.next;
5911
5912                 if (stmt->kind == STATEMENT_EXPRESSION) {
5913                         type = stmt->expression.expression->base.type;
5914                 }
5915         } else {
5916                 warningf(&expression->base.source_position, "empty statement expression ({})");
5917         }
5918         expression->base.type = type;
5919
5920         expect(')');
5921
5922         return expression;
5923 end_error:
5924         return create_invalid_expression();
5925 }
5926
5927 /**
5928  * Parse a braced expression.
5929  */
5930 static expression_t *parse_brace_expression(void)
5931 {
5932         eat('(');
5933         add_anchor_token(')');
5934
5935         switch(token.type) {
5936         case '{':
5937                 /* gcc extension: a statement expression */
5938                 return parse_statement_expression();
5939
5940         TYPE_QUALIFIERS
5941         TYPE_SPECIFIERS
5942                 return parse_cast();
5943         case T_IDENTIFIER:
5944                 if (is_typedef_symbol(token.v.symbol)) {
5945                         return parse_cast();
5946                 }
5947         }
5948
5949         expression_t *result = parse_expression();
5950         rem_anchor_token(')');
5951         expect(')');
5952
5953         return result;
5954 end_error:
5955         return create_invalid_expression();
5956 }
5957
5958 static expression_t *parse_function_keyword(void)
5959 {
5960         next_token();
5961         /* TODO */
5962
5963         if (current_function == NULL) {
5964                 errorf(HERE, "'__func__' used outside of a function");
5965         }
5966
5967         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5968         expression->base.type     = type_char_ptr;
5969         expression->funcname.kind = FUNCNAME_FUNCTION;
5970
5971         return expression;
5972 }
5973
5974 static expression_t *parse_pretty_function_keyword(void)
5975 {
5976         eat(T___PRETTY_FUNCTION__);
5977
5978         if (current_function == NULL) {
5979                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
5980         }
5981
5982         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5983         expression->base.type     = type_char_ptr;
5984         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
5985
5986         return expression;
5987 }
5988
5989 static expression_t *parse_funcsig_keyword(void)
5990 {
5991         eat(T___FUNCSIG__);
5992
5993         if (current_function == NULL) {
5994                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
5995         }
5996
5997         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
5998         expression->base.type     = type_char_ptr;
5999         expression->funcname.kind = FUNCNAME_FUNCSIG;
6000
6001         return expression;
6002 }
6003
6004 static expression_t *parse_funcdname_keyword(void)
6005 {
6006         eat(T___FUNCDNAME__);
6007
6008         if (current_function == NULL) {
6009                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6010         }
6011
6012         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6013         expression->base.type     = type_char_ptr;
6014         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6015
6016         return expression;
6017 }
6018
6019 static designator_t *parse_designator(void)
6020 {
6021         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6022         result->source_position = *HERE;
6023
6024         if (token.type != T_IDENTIFIER) {
6025                 parse_error_expected("while parsing member designator",
6026                                      T_IDENTIFIER, NULL);
6027                 return NULL;
6028         }
6029         result->symbol = token.v.symbol;
6030         next_token();
6031
6032         designator_t *last_designator = result;
6033         while(true) {
6034                 if (token.type == '.') {
6035                         next_token();
6036                         if (token.type != T_IDENTIFIER) {
6037                                 parse_error_expected("while parsing member designator",
6038                                                      T_IDENTIFIER, NULL);
6039                                 return NULL;
6040                         }
6041                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6042                         designator->source_position = *HERE;
6043                         designator->symbol          = token.v.symbol;
6044                         next_token();
6045
6046                         last_designator->next = designator;
6047                         last_designator       = designator;
6048                         continue;
6049                 }
6050                 if (token.type == '[') {
6051                         next_token();
6052                         add_anchor_token(']');
6053                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6054                         designator->source_position = *HERE;
6055                         designator->array_index     = parse_expression();
6056                         rem_anchor_token(']');
6057                         expect(']');
6058                         if (designator->array_index == NULL) {
6059                                 return NULL;
6060                         }
6061
6062                         last_designator->next = designator;
6063                         last_designator       = designator;
6064                         continue;
6065                 }
6066                 break;
6067         }
6068
6069         return result;
6070 end_error:
6071         return NULL;
6072 }
6073
6074 /**
6075  * Parse the __builtin_offsetof() expression.
6076  */
6077 static expression_t *parse_offsetof(void)
6078 {
6079         eat(T___builtin_offsetof);
6080
6081         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6082         expression->base.type    = type_size_t;
6083
6084         expect('(');
6085         add_anchor_token(',');
6086         type_t *type = parse_typename();
6087         rem_anchor_token(',');
6088         expect(',');
6089         add_anchor_token(')');
6090         designator_t *designator = parse_designator();
6091         rem_anchor_token(')');
6092         expect(')');
6093
6094         expression->offsetofe.type       = type;
6095         expression->offsetofe.designator = designator;
6096
6097         type_path_t path;
6098         memset(&path, 0, sizeof(path));
6099         path.top_type = type;
6100         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6101
6102         descend_into_subtype(&path);
6103
6104         if (!walk_designator(&path, designator, true)) {
6105                 return create_invalid_expression();
6106         }
6107
6108         DEL_ARR_F(path.path);
6109
6110         return expression;
6111 end_error:
6112         return create_invalid_expression();
6113 }
6114
6115 /**
6116  * Parses a _builtin_va_start() expression.
6117  */
6118 static expression_t *parse_va_start(void)
6119 {
6120         eat(T___builtin_va_start);
6121
6122         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6123
6124         expect('(');
6125         add_anchor_token(',');
6126         expression->va_starte.ap = parse_assignment_expression();
6127         rem_anchor_token(',');
6128         expect(',');
6129         expression_t *const expr = parse_assignment_expression();
6130         if (expr->kind == EXPR_REFERENCE) {
6131                 declaration_t *const decl = expr->reference.declaration;
6132                 if (decl == NULL)
6133                         return create_invalid_expression();
6134                 if (decl->parent_scope == &current_function->scope &&
6135                     decl->next == NULL) {
6136                         expression->va_starte.parameter = decl;
6137                         expect(')');
6138                         return expression;
6139                 }
6140         }
6141         errorf(&expr->base.source_position,
6142                "second argument of 'va_start' must be last parameter of the current function");
6143 end_error:
6144         return create_invalid_expression();
6145 }
6146
6147 /**
6148  * Parses a _builtin_va_arg() expression.
6149  */
6150 static expression_t *parse_va_arg(void)
6151 {
6152         eat(T___builtin_va_arg);
6153
6154         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6155
6156         expect('(');
6157         expression->va_arge.ap = parse_assignment_expression();
6158         expect(',');
6159         expression->base.type = parse_typename();
6160         expect(')');
6161
6162         return expression;
6163 end_error:
6164         return create_invalid_expression();
6165 }
6166
6167 static expression_t *parse_builtin_symbol(void)
6168 {
6169         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
6170
6171         symbol_t *symbol = token.v.symbol;
6172
6173         expression->builtin_symbol.symbol = symbol;
6174         next_token();
6175
6176         type_t *type = get_builtin_symbol_type(symbol);
6177         type = automatic_type_conversion(type);
6178
6179         expression->base.type = type;
6180         return expression;
6181 }
6182
6183 /**
6184  * Parses a __builtin_constant() expression.
6185  */
6186 static expression_t *parse_builtin_constant(void)
6187 {
6188         eat(T___builtin_constant_p);
6189
6190         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6191
6192         expect('(');
6193         add_anchor_token(')');
6194         expression->builtin_constant.value = parse_assignment_expression();
6195         rem_anchor_token(')');
6196         expect(')');
6197         expression->base.type = type_int;
6198
6199         return expression;
6200 end_error:
6201         return create_invalid_expression();
6202 }
6203
6204 /**
6205  * Parses a __builtin_prefetch() expression.
6206  */
6207 static expression_t *parse_builtin_prefetch(void)
6208 {
6209         eat(T___builtin_prefetch);
6210
6211         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
6212
6213         expect('(');
6214         add_anchor_token(')');
6215         expression->builtin_prefetch.adr = parse_assignment_expression();
6216         if (token.type == ',') {
6217                 next_token();
6218                 expression->builtin_prefetch.rw = parse_assignment_expression();
6219         }
6220         if (token.type == ',') {
6221                 next_token();
6222                 expression->builtin_prefetch.locality = parse_assignment_expression();
6223         }
6224         rem_anchor_token(')');
6225         expect(')');
6226         expression->base.type = type_void;
6227
6228         return expression;
6229 end_error:
6230         return create_invalid_expression();
6231 }
6232
6233 /**
6234  * Parses a __builtin_is_*() compare expression.
6235  */
6236 static expression_t *parse_compare_builtin(void)
6237 {
6238         expression_t *expression;
6239
6240         switch(token.type) {
6241         case T___builtin_isgreater:
6242                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6243                 break;
6244         case T___builtin_isgreaterequal:
6245                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6246                 break;
6247         case T___builtin_isless:
6248                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6249                 break;
6250         case T___builtin_islessequal:
6251                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6252                 break;
6253         case T___builtin_islessgreater:
6254                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6255                 break;
6256         case T___builtin_isunordered:
6257                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6258                 break;
6259         default:
6260                 internal_errorf(HERE, "invalid compare builtin found");
6261                 break;
6262         }
6263         expression->base.source_position = *HERE;
6264         next_token();
6265
6266         expect('(');
6267         expression->binary.left = parse_assignment_expression();
6268         expect(',');
6269         expression->binary.right = parse_assignment_expression();
6270         expect(')');
6271
6272         type_t *const orig_type_left  = expression->binary.left->base.type;
6273         type_t *const orig_type_right = expression->binary.right->base.type;
6274
6275         type_t *const type_left  = skip_typeref(orig_type_left);
6276         type_t *const type_right = skip_typeref(orig_type_right);
6277         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6278                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6279                         type_error_incompatible("invalid operands in comparison",
6280                                 &expression->base.source_position, orig_type_left, orig_type_right);
6281                 }
6282         } else {
6283                 semantic_comparison(&expression->binary);
6284         }
6285
6286         return expression;
6287 end_error:
6288         return create_invalid_expression();
6289 }
6290
6291 #if 0
6292 /**
6293  * Parses a __builtin_expect() expression.
6294  */
6295 static expression_t *parse_builtin_expect(void)
6296 {
6297         eat(T___builtin_expect);
6298
6299         expression_t *expression
6300                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
6301
6302         expect('(');
6303         expression->binary.left = parse_assignment_expression();
6304         expect(',');
6305         expression->binary.right = parse_constant_expression();
6306         expect(')');
6307
6308         expression->base.type = expression->binary.left->base.type;
6309
6310         return expression;
6311 end_error:
6312         return create_invalid_expression();
6313 }
6314 #endif
6315
6316 /**
6317  * Parses a MS assume() expression.
6318  */
6319 static expression_t *parse_assume(void)
6320 {
6321         eat(T__assume);
6322
6323         expression_t *expression
6324                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
6325
6326         expect('(');
6327         add_anchor_token(')');
6328         expression->unary.value = parse_assignment_expression();
6329         rem_anchor_token(')');
6330         expect(')');
6331
6332         expression->base.type = type_void;
6333         return expression;
6334 end_error:
6335         return create_invalid_expression();
6336 }
6337
6338 /**
6339  * Parse a microsoft __noop expression.
6340  */
6341 static expression_t *parse_noop_expression(void)
6342 {
6343         source_position_t source_position = *HERE;
6344         eat(T___noop);
6345
6346         if (token.type == '(') {
6347                 /* parse arguments */
6348                 eat('(');
6349                 add_anchor_token(')');
6350                 add_anchor_token(',');
6351
6352                 if (token.type != ')') {
6353                         while(true) {
6354                                 (void)parse_assignment_expression();
6355                                 if (token.type != ',')
6356                                         break;
6357                                 next_token();
6358                         }
6359                 }
6360         }
6361         rem_anchor_token(',');
6362         rem_anchor_token(')');
6363         expect(')');
6364
6365         /* the result is a (int)0 */
6366         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6367         cnst->base.source_position = source_position;
6368         cnst->base.type            = type_int;
6369         cnst->conste.v.int_value   = 0;
6370         cnst->conste.is_ms_noop    = true;
6371
6372         return cnst;
6373
6374 end_error:
6375         return create_invalid_expression();
6376 }
6377
6378 /**
6379  * Parses a primary expression.
6380  */
6381 static expression_t *parse_primary_expression(void)
6382 {
6383         switch (token.type) {
6384                 case T_INTEGER:                  return parse_int_const();
6385                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
6386                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
6387                 case T_FLOATINGPOINT:            return parse_float_const();
6388                 case T_STRING_LITERAL:
6389                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
6390                 case T_IDENTIFIER:               return parse_reference();
6391                 case T___FUNCTION__:
6392                 case T___func__:                 return parse_function_keyword();
6393                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
6394                 case T___FUNCSIG__:              return parse_funcsig_keyword();
6395                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
6396                 case T___builtin_offsetof:       return parse_offsetof();
6397                 case T___builtin_va_start:       return parse_va_start();
6398                 case T___builtin_va_arg:         return parse_va_arg();
6399                 case T___builtin_expect:
6400                 case T___builtin_alloca:
6401                 case T___builtin_nan:
6402                 case T___builtin_nand:
6403                 case T___builtin_nanf:
6404                 case T___builtin_huge_val:
6405                 case T___builtin_va_end:         return parse_builtin_symbol();
6406                 case T___builtin_isgreater:
6407                 case T___builtin_isgreaterequal:
6408                 case T___builtin_isless:
6409                 case T___builtin_islessequal:
6410                 case T___builtin_islessgreater:
6411                 case T___builtin_isunordered:    return parse_compare_builtin();
6412                 case T___builtin_constant_p:     return parse_builtin_constant();
6413                 case T___builtin_prefetch:       return parse_builtin_prefetch();
6414                 case T__assume:                  return parse_assume();
6415
6416                 case '(':                        return parse_brace_expression();
6417                 case T___noop:                   return parse_noop_expression();
6418         }
6419
6420         errorf(HERE, "unexpected token %K, expected an expression", &token);
6421         return create_invalid_expression();
6422 }
6423
6424 /**
6425  * Check if the expression has the character type and issue a warning then.
6426  */
6427 static void check_for_char_index_type(const expression_t *expression)
6428 {
6429         type_t       *const type      = expression->base.type;
6430         const type_t *const base_type = skip_typeref(type);
6431
6432         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
6433                         warning.char_subscripts) {
6434                 warningf(&expression->base.source_position,
6435                          "array subscript has type '%T'", type);
6436         }
6437 }
6438
6439 static expression_t *parse_array_expression(unsigned precedence,
6440                                             expression_t *left)
6441 {
6442         (void) precedence;
6443
6444         eat('[');
6445         add_anchor_token(']');
6446
6447         expression_t *inside = parse_expression();
6448
6449         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
6450
6451         array_access_expression_t *array_access = &expression->array_access;
6452
6453         type_t *const orig_type_left   = left->base.type;
6454         type_t *const orig_type_inside = inside->base.type;
6455
6456         type_t *const type_left   = skip_typeref(orig_type_left);
6457         type_t *const type_inside = skip_typeref(orig_type_inside);
6458
6459         type_t *return_type;
6460         if (is_type_pointer(type_left)) {
6461                 return_type             = type_left->pointer.points_to;
6462                 array_access->array_ref = left;
6463                 array_access->index     = inside;
6464                 check_for_char_index_type(inside);
6465         } else if (is_type_pointer(type_inside)) {
6466                 return_type             = type_inside->pointer.points_to;
6467                 array_access->array_ref = inside;
6468                 array_access->index     = left;
6469                 array_access->flipped   = true;
6470                 check_for_char_index_type(left);
6471         } else {
6472                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
6473                         errorf(HERE,
6474                                 "array access on object with non-pointer types '%T', '%T'",
6475                                 orig_type_left, orig_type_inside);
6476                 }
6477                 return_type             = type_error_type;
6478                 array_access->array_ref = create_invalid_expression();
6479         }
6480
6481         rem_anchor_token(']');
6482         if (token.type != ']') {
6483                 parse_error_expected("Problem while parsing array access", ']', NULL);
6484                 return expression;
6485         }
6486         next_token();
6487
6488         return_type           = automatic_type_conversion(return_type);
6489         expression->base.type = return_type;
6490
6491         return expression;
6492 }
6493
6494 static expression_t *parse_typeprop(expression_kind_t const kind,
6495                                     source_position_t const pos,
6496                                     unsigned const precedence)
6497 {
6498         expression_t *tp_expression = allocate_expression_zero(kind);
6499         tp_expression->base.type            = type_size_t;
6500         tp_expression->base.source_position = pos;
6501
6502         char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
6503
6504         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
6505                 next_token();
6506                 add_anchor_token(')');
6507                 type_t* const orig_type = parse_typename();
6508                 tp_expression->typeprop.type = orig_type;
6509
6510                 type_t const* const type = skip_typeref(orig_type);
6511                 char const* const wrong_type =
6512                         is_type_incomplete(type)    ? "incomplete"          :
6513                         type->kind == TYPE_FUNCTION ? "function designator" :
6514                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6515                         NULL;
6516                 if (wrong_type != NULL) {
6517                         errorf(&pos, "operand of %s expression must not be %s type '%T'",
6518                                what, wrong_type, type);
6519                 }
6520
6521                 rem_anchor_token(')');
6522                 expect(')');
6523         } else {
6524                 expression_t *expression = parse_sub_expression(precedence);
6525
6526                 type_t* const orig_type = revert_automatic_type_conversion(expression);
6527                 expression->base.type = orig_type;
6528
6529                 type_t const* const type = skip_typeref(orig_type);
6530                 char const* const wrong_type =
6531                         is_type_incomplete(type)    ? "incomplete"          :
6532                         type->kind == TYPE_FUNCTION ? "function designator" :
6533                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6534                         NULL;
6535                 if (wrong_type != NULL) {
6536                         errorf(&pos, "operand of %s expression must not be expression of %s type '%T'", what, wrong_type, type);
6537                 }
6538
6539                 tp_expression->typeprop.type          = expression->base.type;
6540                 tp_expression->typeprop.tp_expression = expression;
6541         }
6542
6543         return tp_expression;
6544 end_error:
6545         return create_invalid_expression();
6546 }
6547
6548 static expression_t *parse_sizeof(unsigned precedence)
6549 {
6550         source_position_t pos = *HERE;
6551         eat(T_sizeof);
6552         return parse_typeprop(EXPR_SIZEOF, pos, precedence);
6553 }
6554
6555 static expression_t *parse_alignof(unsigned precedence)
6556 {
6557         source_position_t pos = *HERE;
6558         eat(T___alignof__);
6559         return parse_typeprop(EXPR_ALIGNOF, pos, precedence);
6560 }
6561
6562 static expression_t *parse_select_expression(unsigned precedence,
6563                                              expression_t *compound)
6564 {
6565         (void) precedence;
6566         assert(token.type == '.' || token.type == T_MINUSGREATER);
6567
6568         bool is_pointer = (token.type == T_MINUSGREATER);
6569         next_token();
6570
6571         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
6572         select->select.compound = compound;
6573
6574         if (token.type != T_IDENTIFIER) {
6575                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
6576                 return select;
6577         }
6578         symbol_t *symbol      = token.v.symbol;
6579         select->select.symbol = symbol;
6580         next_token();
6581
6582         type_t *const orig_type = compound->base.type;
6583         type_t *const type      = skip_typeref(orig_type);
6584
6585         type_t *type_left = type;
6586         if (is_pointer) {
6587                 if (!is_type_pointer(type)) {
6588                         if (is_type_valid(type)) {
6589                                 errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
6590                         }
6591                         return create_invalid_expression();
6592                 }
6593                 type_left = type->pointer.points_to;
6594         }
6595         type_left = skip_typeref(type_left);
6596
6597         if (type_left->kind != TYPE_COMPOUND_STRUCT &&
6598             type_left->kind != TYPE_COMPOUND_UNION) {
6599                 if (is_type_valid(type_left)) {
6600                         errorf(HERE, "request for member '%Y' in something not a struct or "
6601                                "union, but '%T'", symbol, type_left);
6602                 }
6603                 return create_invalid_expression();
6604         }
6605
6606         declaration_t *const declaration = type_left->compound.declaration;
6607
6608         if (!declaration->init.complete) {
6609                 errorf(HERE, "request for member '%Y' of incomplete type '%T'",
6610                        symbol, type_left);
6611                 return create_invalid_expression();
6612         }
6613
6614         declaration_t *iter = find_compound_entry(declaration, symbol);
6615         if (iter == NULL) {
6616                 errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
6617                 return create_invalid_expression();
6618         }
6619
6620         /* we always do the auto-type conversions; the & and sizeof parser contains
6621          * code to revert this! */
6622         type_t *expression_type = automatic_type_conversion(iter->type);
6623
6624         select->select.compound_entry = iter;
6625         select->base.type             = expression_type;
6626
6627         type_t *skipped = skip_typeref(iter->type);
6628         if (skipped->kind == TYPE_BITFIELD) {
6629                 select->base.type = skipped->bitfield.base_type;
6630         }
6631
6632         return select;
6633 }
6634
6635 static void check_call_argument(const function_parameter_t *parameter,
6636                                 call_argument_t *argument)
6637 {
6638         type_t         *expected_type      = parameter->type;
6639         type_t         *expected_type_skip = skip_typeref(expected_type);
6640         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
6641         expression_t   *arg_expr           = argument->expression;
6642
6643         /* handle transparent union gnu extension */
6644         if (is_type_union(expected_type_skip)
6645                         && (expected_type_skip->base.modifiers
6646                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
6647                 declaration_t  *union_decl = expected_type_skip->compound.declaration;
6648
6649                 declaration_t *declaration = union_decl->scope.declarations;
6650                 type_t        *best_type   = NULL;
6651                 for ( ; declaration != NULL; declaration = declaration->next) {
6652                         type_t *decl_type = declaration->type;
6653                         error = semantic_assign(decl_type, arg_expr);
6654                         if (error == ASSIGN_ERROR_INCOMPATIBLE
6655                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
6656                                 continue;
6657
6658                         if (error == ASSIGN_SUCCESS) {
6659                                 best_type = decl_type;
6660                         } else if (best_type == NULL) {
6661                                 best_type = decl_type;
6662                         }
6663                 }
6664
6665                 if (best_type != NULL) {
6666                         expected_type = best_type;
6667                 }
6668         }
6669
6670         error                = semantic_assign(expected_type, arg_expr);
6671         argument->expression = create_implicit_cast(argument->expression,
6672                                                     expected_type);
6673
6674         /* TODO report exact scope in error messages (like "in 3rd parameter") */
6675         report_assign_error(error, expected_type, arg_expr,     "function call",
6676                             &arg_expr->base.source_position);
6677 }
6678
6679 /**
6680  * Parse a call expression, ie. expression '( ... )'.
6681  *
6682  * @param expression  the function address
6683  */
6684 static expression_t *parse_call_expression(unsigned precedence,
6685                                            expression_t *expression)
6686 {
6687         (void) precedence;
6688         expression_t *result = allocate_expression_zero(EXPR_CALL);
6689         result->base.source_position = expression->base.source_position;
6690
6691         call_expression_t *call = &result->call;
6692         call->function          = expression;
6693
6694         type_t *const orig_type = expression->base.type;
6695         type_t *const type      = skip_typeref(orig_type);
6696
6697         function_type_t *function_type = NULL;
6698         if (is_type_pointer(type)) {
6699                 type_t *const to_type = skip_typeref(type->pointer.points_to);
6700
6701                 if (is_type_function(to_type)) {
6702                         function_type   = &to_type->function;
6703                         call->base.type = function_type->return_type;
6704                 }
6705         }
6706
6707         if (function_type == NULL && is_type_valid(type)) {
6708                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
6709         }
6710
6711         /* parse arguments */
6712         eat('(');
6713         add_anchor_token(')');
6714         add_anchor_token(',');
6715
6716         if (token.type != ')') {
6717                 call_argument_t *last_argument = NULL;
6718
6719                 while(true) {
6720                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
6721
6722                         argument->expression = parse_assignment_expression();
6723                         if (last_argument == NULL) {
6724                                 call->arguments = argument;
6725                         } else {
6726                                 last_argument->next = argument;
6727                         }
6728                         last_argument = argument;
6729
6730                         if (token.type != ',')
6731                                 break;
6732                         next_token();
6733                 }
6734         }
6735         rem_anchor_token(',');
6736         rem_anchor_token(')');
6737         expect(')');
6738
6739         if (function_type == NULL)
6740                 return result;
6741
6742         function_parameter_t *parameter = function_type->parameters;
6743         call_argument_t      *argument  = call->arguments;
6744         if (!function_type->unspecified_parameters) {
6745                 for( ; parameter != NULL && argument != NULL;
6746                                 parameter = parameter->next, argument = argument->next) {
6747                         check_call_argument(parameter, argument);
6748                 }
6749
6750                 if (parameter != NULL) {
6751                         errorf(HERE, "too few arguments to function '%E'", expression);
6752                 } else if (argument != NULL && !function_type->variadic) {
6753                         errorf(HERE, "too many arguments to function '%E'", expression);
6754                 }
6755         }
6756
6757         /* do default promotion */
6758         for( ; argument != NULL; argument = argument->next) {
6759                 type_t *type = argument->expression->base.type;
6760
6761                 type = get_default_promoted_type(type);
6762
6763                 argument->expression
6764                         = create_implicit_cast(argument->expression, type);
6765         }
6766
6767         check_format(&result->call);
6768
6769         return result;
6770 end_error:
6771         return create_invalid_expression();
6772 }
6773
6774 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
6775
6776 static bool same_compound_type(const type_t *type1, const type_t *type2)
6777 {
6778         return
6779                 is_type_compound(type1) &&
6780                 type1->kind == type2->kind &&
6781                 type1->compound.declaration == type2->compound.declaration;
6782 }
6783
6784 /**
6785  * Parse a conditional expression, ie. 'expression ? ... : ...'.
6786  *
6787  * @param expression  the conditional expression
6788  */
6789 static expression_t *parse_conditional_expression(unsigned precedence,
6790                                                   expression_t *expression)
6791 {
6792         eat('?');
6793         add_anchor_token(':');
6794
6795         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
6796
6797         conditional_expression_t *conditional = &result->conditional;
6798         conditional->condition = expression;
6799
6800         /* 6.5.15.2 */
6801         type_t *const condition_type_orig = expression->base.type;
6802         type_t *const condition_type      = skip_typeref(condition_type_orig);
6803         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
6804                 type_error("expected a scalar type in conditional condition",
6805                            &expression->base.source_position, condition_type_orig);
6806         }
6807
6808         expression_t *true_expression = parse_expression();
6809         rem_anchor_token(':');
6810         expect(':');
6811         expression_t *false_expression = parse_sub_expression(precedence);
6812
6813         type_t *const orig_true_type  = true_expression->base.type;
6814         type_t *const orig_false_type = false_expression->base.type;
6815         type_t *const true_type       = skip_typeref(orig_true_type);
6816         type_t *const false_type      = skip_typeref(orig_false_type);
6817
6818         /* 6.5.15.3 */
6819         type_t *result_type;
6820         if (is_type_atomic(true_type, ATOMIC_TYPE_VOID) ||
6821                 is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
6822                 if (!is_type_atomic(true_type, ATOMIC_TYPE_VOID)
6823                     || !is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
6824                         warningf(&expression->base.source_position,
6825                                         "ISO C forbids conditional expression with only one void side");
6826                 }
6827                 result_type = type_void;
6828         } else if (is_type_arithmetic(true_type)
6829                    && is_type_arithmetic(false_type)) {
6830                 result_type = semantic_arithmetic(true_type, false_type);
6831
6832                 true_expression  = create_implicit_cast(true_expression, result_type);
6833                 false_expression = create_implicit_cast(false_expression, result_type);
6834
6835                 conditional->true_expression  = true_expression;
6836                 conditional->false_expression = false_expression;
6837                 conditional->base.type        = result_type;
6838         } else if (same_compound_type(true_type, false_type)) {
6839                 /* just take 1 of the 2 types */
6840                 result_type = true_type;
6841         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
6842                 type_t *pointer_type;
6843                 type_t *other_type;
6844                 expression_t *other_expression;
6845                 if (is_type_pointer(true_type) &&
6846                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
6847                         pointer_type     = true_type;
6848                         other_type       = false_type;
6849                         other_expression = false_expression;
6850                 } else {
6851                         pointer_type     = false_type;
6852                         other_type       = true_type;
6853                         other_expression = true_expression;
6854                 }
6855
6856                 if (is_null_pointer_constant(other_expression)) {
6857                         result_type = pointer_type;
6858                 } else if (is_type_pointer(other_type)) {
6859                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
6860                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
6861
6862                         type_t *to;
6863                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
6864                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
6865                                 to = type_void;
6866                         } else if (types_compatible(get_unqualified_type(to1),
6867                                                     get_unqualified_type(to2))) {
6868                                 to = to1;
6869                         } else {
6870                                 warningf(&expression->base.source_position,
6871                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
6872                                         true_type, false_type);
6873                                 to = type_void;
6874                         }
6875
6876                         type_t *const copy = duplicate_type(to);
6877                         copy->base.qualifiers = to1->base.qualifiers | to2->base.qualifiers;
6878
6879                         type_t *const type = typehash_insert(copy);
6880                         if (type != copy)
6881                                 free_type(copy);
6882
6883                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
6884                 } else if (is_type_integer(other_type)) {
6885                         warningf(&expression->base.source_position,
6886                                         "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
6887                         result_type = pointer_type;
6888                 } else {
6889                         type_error_incompatible("while parsing conditional",
6890                                         &expression->base.source_position, true_type, false_type);
6891                         result_type = type_error_type;
6892                 }
6893         } else {
6894                 /* TODO: one pointer to void*, other some pointer */
6895
6896                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
6897                         type_error_incompatible("while parsing conditional",
6898                                                 &expression->base.source_position, true_type,
6899                                                 false_type);
6900                 }
6901                 result_type = type_error_type;
6902         }
6903
6904         conditional->true_expression
6905                 = create_implicit_cast(true_expression, result_type);
6906         conditional->false_expression
6907                 = create_implicit_cast(false_expression, result_type);
6908         conditional->base.type = result_type;
6909         return result;
6910 end_error:
6911         return create_invalid_expression();
6912 }
6913
6914 /**
6915  * Parse an extension expression.
6916  */
6917 static expression_t *parse_extension(unsigned precedence)
6918 {
6919         eat(T___extension__);
6920
6921         /* TODO enable extensions */
6922         expression_t *expression = parse_sub_expression(precedence);
6923         /* TODO disable extensions */
6924         return expression;
6925 }
6926
6927 /**
6928  * Parse a __builtin_classify_type() expression.
6929  */
6930 static expression_t *parse_builtin_classify_type(const unsigned precedence)
6931 {
6932         eat(T___builtin_classify_type);
6933
6934         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
6935         result->base.type    = type_int;
6936
6937         expect('(');
6938         add_anchor_token(')');
6939         expression_t *expression = parse_sub_expression(precedence);
6940         rem_anchor_token(')');
6941         expect(')');
6942         result->classify_type.type_expression = expression;
6943
6944         return result;
6945 end_error:
6946         return create_invalid_expression();
6947 }
6948
6949 static bool check_pointer_arithmetic(const source_position_t *source_position,
6950                                      type_t *pointer_type,
6951                                      type_t *orig_pointer_type)
6952 {
6953         type_t *points_to = pointer_type->pointer.points_to;
6954         points_to = skip_typeref(points_to);
6955
6956         if (is_type_incomplete(points_to) &&
6957                         (! (c_mode & _GNUC)
6958                          || !is_type_atomic(points_to, ATOMIC_TYPE_VOID))) {
6959                 errorf(source_position,
6960                            "arithmetic with pointer to incomplete type '%T' not allowed",
6961                            orig_pointer_type);
6962                 return false;
6963         } else if (is_type_function(points_to)) {
6964                 errorf(source_position,
6965                            "arithmetic with pointer to function type '%T' not allowed",
6966                            orig_pointer_type);
6967                 return false;
6968         }
6969         return true;
6970 }
6971
6972 static void semantic_incdec(unary_expression_t *expression)
6973 {
6974         type_t *const orig_type = expression->value->base.type;
6975         type_t *const type      = skip_typeref(orig_type);
6976         if (is_type_pointer(type)) {
6977                 if (!check_pointer_arithmetic(&expression->base.source_position,
6978                                               type, orig_type)) {
6979                         return;
6980                 }
6981         } else if (!is_type_real(type) && is_type_valid(type)) {
6982                 /* TODO: improve error message */
6983                 errorf(&expression->base.source_position,
6984                        "operation needs an arithmetic or pointer type");
6985                 return;
6986         }
6987         expression->base.type = orig_type;
6988 }
6989
6990 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
6991 {
6992         type_t *const orig_type = expression->value->base.type;
6993         type_t *const type      = skip_typeref(orig_type);
6994         if (!is_type_arithmetic(type)) {
6995                 if (is_type_valid(type)) {
6996                         /* TODO: improve error message */
6997                         errorf(&expression->base.source_position,
6998                                "operation needs an arithmetic type");
6999                 }
7000                 return;
7001         }
7002
7003         expression->base.type = orig_type;
7004 }
7005
7006 static void semantic_not(unary_expression_t *expression)
7007 {
7008         type_t *const orig_type = expression->value->base.type;
7009         type_t *const type      = skip_typeref(orig_type);
7010         if (!is_type_scalar(type) && is_type_valid(type)) {
7011                 errorf(&expression->base.source_position,
7012                        "operand of ! must be of scalar type");
7013         }
7014
7015         expression->base.type = type_int;
7016 }
7017
7018 static void semantic_unexpr_integer(unary_expression_t *expression)
7019 {
7020         type_t *const orig_type = expression->value->base.type;
7021         type_t *const type      = skip_typeref(orig_type);
7022         if (!is_type_integer(type)) {
7023                 if (is_type_valid(type)) {
7024                         errorf(&expression->base.source_position,
7025                                "operand of ~ must be of integer type");
7026                 }
7027                 return;
7028         }
7029
7030         expression->base.type = orig_type;
7031 }
7032
7033 static void semantic_dereference(unary_expression_t *expression)
7034 {
7035         type_t *const orig_type = expression->value->base.type;
7036         type_t *const type      = skip_typeref(orig_type);
7037         if (!is_type_pointer(type)) {
7038                 if (is_type_valid(type)) {
7039                         errorf(&expression->base.source_position,
7040                                "Unary '*' needs pointer or arrray type, but type '%T' given", orig_type);
7041                 }
7042                 return;
7043         }
7044
7045         type_t *result_type   = type->pointer.points_to;
7046         result_type           = automatic_type_conversion(result_type);
7047         expression->base.type = result_type;
7048 }
7049
7050 static void set_address_taken(expression_t *expression, bool may_be_register)
7051 {
7052         if (expression->kind != EXPR_REFERENCE)
7053                 return;
7054
7055         declaration_t *const declaration = expression->reference.declaration;
7056         /* happens for parse errors */
7057         if (declaration == NULL)
7058                 return;
7059
7060         if (declaration->storage_class == STORAGE_CLASS_REGISTER && !may_be_register) {
7061                 errorf(&expression->base.source_position,
7062                                 "address of register variable '%Y' requested",
7063                                 declaration->symbol);
7064         } else {
7065                 declaration->address_taken = 1;
7066         }
7067 }
7068
7069 /**
7070  * Check the semantic of the address taken expression.
7071  */
7072 static void semantic_take_addr(unary_expression_t *expression)
7073 {
7074         expression_t *value = expression->value;
7075         value->base.type    = revert_automatic_type_conversion(value);
7076
7077         type_t *orig_type = value->base.type;
7078         if (!is_type_valid(orig_type))
7079                 return;
7080
7081         set_address_taken(value, false);
7082
7083         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
7084 }
7085
7086 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc)   \
7087 static expression_t *parse_##unexpression_type(unsigned precedence)            \
7088 {                                                                              \
7089         expression_t *unary_expression                                             \
7090                 = allocate_expression_zero(unexpression_type);                         \
7091         unary_expression->base.source_position = *HERE;                            \
7092         eat(token_type);                                                           \
7093         unary_expression->unary.value = parse_sub_expression(precedence);          \
7094                                                                                    \
7095         sfunc(&unary_expression->unary);                                           \
7096                                                                                    \
7097         return unary_expression;                                                   \
7098 }
7099
7100 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
7101                                semantic_unexpr_arithmetic)
7102 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
7103                                semantic_unexpr_arithmetic)
7104 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
7105                                semantic_not)
7106 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
7107                                semantic_dereference)
7108 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
7109                                semantic_take_addr)
7110 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
7111                                semantic_unexpr_integer)
7112 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
7113                                semantic_incdec)
7114 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
7115                                semantic_incdec)
7116
7117 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
7118                                                sfunc)                         \
7119 static expression_t *parse_##unexpression_type(unsigned precedence,           \
7120                                                expression_t *left)            \
7121 {                                                                             \
7122         (void) precedence;                                                        \
7123                                                                               \
7124         expression_t *unary_expression                                            \
7125                 = allocate_expression_zero(unexpression_type);                        \
7126         unary_expression->base.source_position = *HERE;                           \
7127         eat(token_type);                                                          \
7128         unary_expression->unary.value          = left;                            \
7129                                                                                   \
7130         sfunc(&unary_expression->unary);                                          \
7131                                                                               \
7132         return unary_expression;                                                  \
7133 }
7134
7135 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
7136                                        EXPR_UNARY_POSTFIX_INCREMENT,
7137                                        semantic_incdec)
7138 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
7139                                        EXPR_UNARY_POSTFIX_DECREMENT,
7140                                        semantic_incdec)
7141
7142 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
7143 {
7144         /* TODO: handle complex + imaginary types */
7145
7146         /* § 6.3.1.8 Usual arithmetic conversions */
7147         if (type_left == type_long_double || type_right == type_long_double) {
7148                 return type_long_double;
7149         } else if (type_left == type_double || type_right == type_double) {
7150                 return type_double;
7151         } else if (type_left == type_float || type_right == type_float) {
7152                 return type_float;
7153         }
7154
7155         type_left  = promote_integer(type_left);
7156         type_right = promote_integer(type_right);
7157
7158         if (type_left == type_right)
7159                 return type_left;
7160
7161         bool const signed_left  = is_type_signed(type_left);
7162         bool const signed_right = is_type_signed(type_right);
7163         int  const rank_left    = get_rank(type_left);
7164         int  const rank_right   = get_rank(type_right);
7165
7166         if (signed_left == signed_right)
7167                 return rank_left >= rank_right ? type_left : type_right;
7168
7169         int     s_rank;
7170         int     u_rank;
7171         type_t *s_type;
7172         type_t *u_type;
7173         if (signed_left) {
7174                 s_rank = rank_left;
7175                 s_type = type_left;
7176                 u_rank = rank_right;
7177                 u_type = type_right;
7178         } else {
7179                 s_rank = rank_right;
7180                 s_type = type_right;
7181                 u_rank = rank_left;
7182                 u_type = type_left;
7183         }
7184
7185         if (u_rank >= s_rank)
7186                 return u_type;
7187
7188         if (get_atomic_type_size(s_rank) > get_atomic_type_size(u_rank))
7189                 return s_type;
7190
7191         switch (s_rank) {
7192                 case ATOMIC_TYPE_INT:      return type_int;
7193                 case ATOMIC_TYPE_LONG:     return type_long;
7194                 case ATOMIC_TYPE_LONGLONG: return type_long_long;
7195
7196                 default: panic("invalid atomic type");
7197         }
7198 }
7199
7200 /**
7201  * Check the semantic restrictions for a binary expression.
7202  */
7203 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
7204 {
7205         expression_t *const left            = expression->left;
7206         expression_t *const right           = expression->right;
7207         type_t       *const orig_type_left  = left->base.type;
7208         type_t       *const orig_type_right = right->base.type;
7209         type_t       *const type_left       = skip_typeref(orig_type_left);
7210         type_t       *const type_right      = skip_typeref(orig_type_right);
7211
7212         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7213                 /* TODO: improve error message */
7214                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7215                         errorf(&expression->base.source_position,
7216                                "operation needs arithmetic types");
7217                 }
7218                 return;
7219         }
7220
7221         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7222         expression->left      = create_implicit_cast(left, arithmetic_type);
7223         expression->right     = create_implicit_cast(right, arithmetic_type);
7224         expression->base.type = arithmetic_type;
7225 }
7226
7227 static void semantic_shift_op(binary_expression_t *expression)
7228 {
7229         expression_t *const left            = expression->left;
7230         expression_t *const right           = expression->right;
7231         type_t       *const orig_type_left  = left->base.type;
7232         type_t       *const orig_type_right = right->base.type;
7233         type_t       *      type_left       = skip_typeref(orig_type_left);
7234         type_t       *      type_right      = skip_typeref(orig_type_right);
7235
7236         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
7237                 /* TODO: improve error message */
7238                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7239                         errorf(&expression->base.source_position,
7240                                "operands of shift operation must have integer types");
7241                 }
7242                 return;
7243         }
7244
7245         type_left  = promote_integer(type_left);
7246         type_right = promote_integer(type_right);
7247
7248         expression->left      = create_implicit_cast(left, type_left);
7249         expression->right     = create_implicit_cast(right, type_right);
7250         expression->base.type = type_left;
7251 }
7252
7253 static void semantic_add(binary_expression_t *expression)
7254 {
7255         expression_t *const left            = expression->left;
7256         expression_t *const right           = expression->right;
7257         type_t       *const orig_type_left  = left->base.type;
7258         type_t       *const orig_type_right = right->base.type;
7259         type_t       *const type_left       = skip_typeref(orig_type_left);
7260         type_t       *const type_right      = skip_typeref(orig_type_right);
7261
7262         /* § 6.5.6 */
7263         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7264                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7265                 expression->left  = create_implicit_cast(left, arithmetic_type);
7266                 expression->right = create_implicit_cast(right, arithmetic_type);
7267                 expression->base.type = arithmetic_type;
7268                 return;
7269         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7270                 check_pointer_arithmetic(&expression->base.source_position,
7271                                          type_left, orig_type_left);
7272                 expression->base.type = type_left;
7273         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
7274                 check_pointer_arithmetic(&expression->base.source_position,
7275                                          type_right, orig_type_right);
7276                 expression->base.type = type_right;
7277         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7278                 errorf(&expression->base.source_position,
7279                        "invalid operands to binary + ('%T', '%T')",
7280                        orig_type_left, orig_type_right);
7281         }
7282 }
7283
7284 static void semantic_sub(binary_expression_t *expression)
7285 {
7286         expression_t            *const left            = expression->left;
7287         expression_t            *const right           = expression->right;
7288         type_t                  *const orig_type_left  = left->base.type;
7289         type_t                  *const orig_type_right = right->base.type;
7290         type_t                  *const type_left       = skip_typeref(orig_type_left);
7291         type_t                  *const type_right      = skip_typeref(orig_type_right);
7292         source_position_t const *const pos             = &expression->base.source_position;
7293
7294         /* § 5.6.5 */
7295         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7296                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7297                 expression->left        = create_implicit_cast(left, arithmetic_type);
7298                 expression->right       = create_implicit_cast(right, arithmetic_type);
7299                 expression->base.type =  arithmetic_type;
7300                 return;
7301         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7302                 check_pointer_arithmetic(&expression->base.source_position,
7303                                          type_left, orig_type_left);
7304                 expression->base.type = type_left;
7305         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7306                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
7307                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
7308                 if (!types_compatible(unqual_left, unqual_right)) {
7309                         errorf(pos,
7310                                "subtracting pointers to incompatible types '%T' and '%T'",
7311                                orig_type_left, orig_type_right);
7312                 } else if (!is_type_object(unqual_left)) {
7313                         if (is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
7314                                 warningf(pos, "subtracting pointers to void");
7315                         } else {
7316                                 errorf(pos, "subtracting pointers to non-object types '%T'",
7317                                        orig_type_left);
7318                         }
7319                 }
7320                 expression->base.type = type_ptrdiff_t;
7321         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7322                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
7323                        orig_type_left, orig_type_right);
7324         }
7325 }
7326
7327 /**
7328  * Check the semantics of comparison expressions.
7329  *
7330  * @param expression   The expression to check.
7331  */
7332 static void semantic_comparison(binary_expression_t *expression)
7333 {
7334         expression_t *left            = expression->left;
7335         expression_t *right           = expression->right;
7336         type_t       *orig_type_left  = left->base.type;
7337         type_t       *orig_type_right = right->base.type;
7338
7339         type_t *type_left  = skip_typeref(orig_type_left);
7340         type_t *type_right = skip_typeref(orig_type_right);
7341
7342         /* TODO non-arithmetic types */
7343         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7344                 /* test for signed vs unsigned compares */
7345                 if (warning.sign_compare &&
7346                     (expression->base.kind != EXPR_BINARY_EQUAL &&
7347                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
7348                     (is_type_signed(type_left) != is_type_signed(type_right))) {
7349
7350                         /* check if 1 of the operands is a constant, in this case we just
7351                          * check wether we can safely represent the resulting constant in
7352                          * the type of the other operand. */
7353                         expression_t *const_expr = NULL;
7354                         expression_t *other_expr = NULL;
7355
7356                         if (is_constant_expression(left)) {
7357                                 const_expr = left;
7358                                 other_expr = right;
7359                         } else if (is_constant_expression(right)) {
7360                                 const_expr = right;
7361                                 other_expr = left;
7362                         }
7363
7364                         if (const_expr != NULL) {
7365                                 type_t *other_type = skip_typeref(other_expr->base.type);
7366                                 long    val        = fold_constant(const_expr);
7367                                 /* TODO: check if val can be represented by other_type */
7368                                 (void) other_type;
7369                                 (void) val;
7370                         }
7371                         warningf(&expression->base.source_position,
7372                                  "comparison between signed and unsigned");
7373                 }
7374                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7375                 expression->left        = create_implicit_cast(left, arithmetic_type);
7376                 expression->right       = create_implicit_cast(right, arithmetic_type);
7377                 expression->base.type   = arithmetic_type;
7378                 if (warning.float_equal &&
7379                     (expression->base.kind == EXPR_BINARY_EQUAL ||
7380                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
7381                     is_type_float(arithmetic_type)) {
7382                         warningf(&expression->base.source_position,
7383                                  "comparing floating point with == or != is unsafe");
7384                 }
7385         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7386                 /* TODO check compatibility */
7387         } else if (is_type_pointer(type_left)) {
7388                 expression->right = create_implicit_cast(right, type_left);
7389         } else if (is_type_pointer(type_right)) {
7390                 expression->left = create_implicit_cast(left, type_right);
7391         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7392                 type_error_incompatible("invalid operands in comparison",
7393                                         &expression->base.source_position,
7394                                         type_left, type_right);
7395         }
7396         expression->base.type = type_int;
7397 }
7398
7399 /**
7400  * Checks if a compound type has constant fields.
7401  */
7402 static bool has_const_fields(const compound_type_t *type)
7403 {
7404         const scope_t       *scope       = &type->declaration->scope;
7405         const declaration_t *declaration = scope->declarations;
7406
7407         for (; declaration != NULL; declaration = declaration->next) {
7408                 if (declaration->namespc != NAMESPACE_NORMAL)
7409                         continue;
7410
7411                 const type_t *decl_type = skip_typeref(declaration->type);
7412                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
7413                         return true;
7414         }
7415         /* TODO */
7416         return false;
7417 }
7418
7419 static bool is_lvalue(const expression_t *expression)
7420 {
7421         switch (expression->kind) {
7422         case EXPR_REFERENCE:
7423         case EXPR_ARRAY_ACCESS:
7424         case EXPR_SELECT:
7425         case EXPR_UNARY_DEREFERENCE:
7426                 return true;
7427
7428         default:
7429                 return false;
7430         }
7431 }
7432
7433 static bool is_valid_assignment_lhs(expression_t const* const left)
7434 {
7435         type_t *const orig_type_left = revert_automatic_type_conversion(left);
7436         type_t *const type_left      = skip_typeref(orig_type_left);
7437
7438         if (!is_lvalue(left)) {
7439                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
7440                        left);
7441                 return false;
7442         }
7443
7444         if (is_type_array(type_left)) {
7445                 errorf(HERE, "cannot assign to arrays ('%E')", left);
7446                 return false;
7447         }
7448         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
7449                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
7450                        orig_type_left);
7451                 return false;
7452         }
7453         if (is_type_incomplete(type_left)) {
7454                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
7455                        left, orig_type_left);
7456                 return false;
7457         }
7458         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
7459                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
7460                        left, orig_type_left);
7461                 return false;
7462         }
7463
7464         return true;
7465 }
7466
7467 static void semantic_arithmetic_assign(binary_expression_t *expression)
7468 {
7469         expression_t *left            = expression->left;
7470         expression_t *right           = expression->right;
7471         type_t       *orig_type_left  = left->base.type;
7472         type_t       *orig_type_right = right->base.type;
7473
7474         if (!is_valid_assignment_lhs(left))
7475                 return;
7476
7477         type_t *type_left  = skip_typeref(orig_type_left);
7478         type_t *type_right = skip_typeref(orig_type_right);
7479
7480         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7481                 /* TODO: improve error message */
7482                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7483                         errorf(&expression->base.source_position,
7484                                "operation needs arithmetic types");
7485                 }
7486                 return;
7487         }
7488
7489         /* combined instructions are tricky. We can't create an implicit cast on
7490          * the left side, because we need the uncasted form for the store.
7491          * The ast2firm pass has to know that left_type must be right_type
7492          * for the arithmetic operation and create a cast by itself */
7493         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7494         expression->right       = create_implicit_cast(right, arithmetic_type);
7495         expression->base.type   = type_left;
7496 }
7497
7498 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
7499 {
7500         expression_t *const left            = expression->left;
7501         expression_t *const right           = expression->right;
7502         type_t       *const orig_type_left  = left->base.type;
7503         type_t       *const orig_type_right = right->base.type;
7504         type_t       *const type_left       = skip_typeref(orig_type_left);
7505         type_t       *const type_right      = skip_typeref(orig_type_right);
7506
7507         if (!is_valid_assignment_lhs(left))
7508                 return;
7509
7510         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7511                 /* combined instructions are tricky. We can't create an implicit cast on
7512                  * the left side, because we need the uncasted form for the store.
7513                  * The ast2firm pass has to know that left_type must be right_type
7514                  * for the arithmetic operation and create a cast by itself */
7515                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
7516                 expression->right     = create_implicit_cast(right, arithmetic_type);
7517                 expression->base.type = type_left;
7518         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7519                 check_pointer_arithmetic(&expression->base.source_position,
7520                                          type_left, orig_type_left);
7521                 expression->base.type = type_left;
7522         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7523                 errorf(&expression->base.source_position,
7524                        "incompatible types '%T' and '%T' in assignment",
7525                        orig_type_left, orig_type_right);
7526         }
7527 }
7528
7529 /**
7530  * Check the semantic restrictions of a logical expression.
7531  */
7532 static void semantic_logical_op(binary_expression_t *expression)
7533 {
7534         expression_t *const left            = expression->left;
7535         expression_t *const right           = expression->right;
7536         type_t       *const orig_type_left  = left->base.type;
7537         type_t       *const orig_type_right = right->base.type;
7538         type_t       *const type_left       = skip_typeref(orig_type_left);
7539         type_t       *const type_right      = skip_typeref(orig_type_right);
7540
7541         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
7542                 /* TODO: improve error message */
7543                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7544                         errorf(&expression->base.source_position,
7545                                "operation needs scalar types");
7546                 }
7547                 return;
7548         }
7549
7550         expression->base.type = type_int;
7551 }
7552
7553 /**
7554  * Check the semantic restrictions of a binary assign expression.
7555  */
7556 static void semantic_binexpr_assign(binary_expression_t *expression)
7557 {
7558         expression_t *left           = expression->left;
7559         type_t       *orig_type_left = left->base.type;
7560
7561         type_t *type_left = revert_automatic_type_conversion(left);
7562         type_left         = skip_typeref(orig_type_left);
7563
7564         if (!is_valid_assignment_lhs(left))
7565                 return;
7566
7567         assign_error_t error = semantic_assign(orig_type_left, expression->right);
7568         report_assign_error(error, orig_type_left, expression->right,
7569                         "assignment", &left->base.source_position);
7570         expression->right = create_implicit_cast(expression->right, orig_type_left);
7571         expression->base.type = orig_type_left;
7572 }
7573
7574 /**
7575  * Determine if the outermost operation (or parts thereof) of the given
7576  * expression has no effect in order to generate a warning about this fact.
7577  * Therefore in some cases this only examines some of the operands of the
7578  * expression (see comments in the function and examples below).
7579  * Examples:
7580  *   f() + 23;    // warning, because + has no effect
7581  *   x || f();    // no warning, because x controls execution of f()
7582  *   x ? y : f(); // warning, because y has no effect
7583  *   (void)x;     // no warning to be able to suppress the warning
7584  * This function can NOT be used for an "expression has definitely no effect"-
7585  * analysis. */
7586 static bool expression_has_effect(const expression_t *const expr)
7587 {
7588         switch (expr->kind) {
7589                 case EXPR_UNKNOWN:                   break;
7590                 case EXPR_INVALID:                   return true; /* do NOT warn */
7591                 case EXPR_REFERENCE:                 return false;
7592                 /* suppress the warning for microsoft __noop operations */
7593                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
7594                 case EXPR_CHARACTER_CONSTANT:        return false;
7595                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
7596                 case EXPR_STRING_LITERAL:            return false;
7597                 case EXPR_WIDE_STRING_LITERAL:       return false;
7598
7599                 case EXPR_CALL: {
7600                         const call_expression_t *const call = &expr->call;
7601                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
7602                                 return true;
7603
7604                         switch (call->function->builtin_symbol.symbol->ID) {
7605                                 case T___builtin_va_end: return true;
7606                                 default:                 return false;
7607                         }
7608                 }
7609
7610                 /* Generate the warning if either the left or right hand side of a
7611                  * conditional expression has no effect */
7612                 case EXPR_CONDITIONAL: {
7613                         const conditional_expression_t *const cond = &expr->conditional;
7614                         return
7615                                 expression_has_effect(cond->true_expression) &&
7616                                 expression_has_effect(cond->false_expression);
7617                 }
7618
7619                 case EXPR_SELECT:                    return false;
7620                 case EXPR_ARRAY_ACCESS:              return false;
7621                 case EXPR_SIZEOF:                    return false;
7622                 case EXPR_CLASSIFY_TYPE:             return false;
7623                 case EXPR_ALIGNOF:                   return false;
7624
7625                 case EXPR_FUNCNAME:                  return false;
7626                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
7627                 case EXPR_BUILTIN_CONSTANT_P:        return false;
7628                 case EXPR_BUILTIN_PREFETCH:          return true;
7629                 case EXPR_OFFSETOF:                  return false;
7630                 case EXPR_VA_START:                  return true;
7631                 case EXPR_VA_ARG:                    return true;
7632                 case EXPR_STATEMENT:                 return true; // TODO
7633                 case EXPR_COMPOUND_LITERAL:          return false;
7634
7635                 case EXPR_UNARY_NEGATE:              return false;
7636                 case EXPR_UNARY_PLUS:                return false;
7637                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
7638                 case EXPR_UNARY_NOT:                 return false;
7639                 case EXPR_UNARY_DEREFERENCE:         return false;
7640                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
7641                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
7642                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
7643                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
7644                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
7645
7646                 /* Treat void casts as if they have an effect in order to being able to
7647                  * suppress the warning */
7648                 case EXPR_UNARY_CAST: {
7649                         type_t *const type = skip_typeref(expr->base.type);
7650                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
7651                 }
7652
7653                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
7654                 case EXPR_UNARY_ASSUME:              return true;
7655
7656                 case EXPR_BINARY_ADD:                return false;
7657                 case EXPR_BINARY_SUB:                return false;
7658                 case EXPR_BINARY_MUL:                return false;
7659                 case EXPR_BINARY_DIV:                return false;
7660                 case EXPR_BINARY_MOD:                return false;
7661                 case EXPR_BINARY_EQUAL:              return false;
7662                 case EXPR_BINARY_NOTEQUAL:           return false;
7663                 case EXPR_BINARY_LESS:               return false;
7664                 case EXPR_BINARY_LESSEQUAL:          return false;
7665                 case EXPR_BINARY_GREATER:            return false;
7666                 case EXPR_BINARY_GREATEREQUAL:       return false;
7667                 case EXPR_BINARY_BITWISE_AND:        return false;
7668                 case EXPR_BINARY_BITWISE_OR:         return false;
7669                 case EXPR_BINARY_BITWISE_XOR:        return false;
7670                 case EXPR_BINARY_SHIFTLEFT:          return false;
7671                 case EXPR_BINARY_SHIFTRIGHT:         return false;
7672                 case EXPR_BINARY_ASSIGN:             return true;
7673                 case EXPR_BINARY_MUL_ASSIGN:         return true;
7674                 case EXPR_BINARY_DIV_ASSIGN:         return true;
7675                 case EXPR_BINARY_MOD_ASSIGN:         return true;
7676                 case EXPR_BINARY_ADD_ASSIGN:         return true;
7677                 case EXPR_BINARY_SUB_ASSIGN:         return true;
7678                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
7679                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
7680                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
7681                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
7682                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
7683
7684                 /* Only examine the right hand side of && and ||, because the left hand
7685                  * side already has the effect of controlling the execution of the right
7686                  * hand side */
7687                 case EXPR_BINARY_LOGICAL_AND:
7688                 case EXPR_BINARY_LOGICAL_OR:
7689                 /* Only examine the right hand side of a comma expression, because the left
7690                  * hand side has a separate warning */
7691                 case EXPR_BINARY_COMMA:
7692                         return expression_has_effect(expr->binary.right);
7693
7694                 case EXPR_BINARY_BUILTIN_EXPECT:     return true;
7695                 case EXPR_BINARY_ISGREATER:          return false;
7696                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
7697                 case EXPR_BINARY_ISLESS:             return false;
7698                 case EXPR_BINARY_ISLESSEQUAL:        return false;
7699                 case EXPR_BINARY_ISLESSGREATER:      return false;
7700                 case EXPR_BINARY_ISUNORDERED:        return false;
7701         }
7702
7703         internal_errorf(HERE, "unexpected expression");
7704 }
7705
7706 static void semantic_comma(binary_expression_t *expression)
7707 {
7708         if (warning.unused_value) {
7709                 const expression_t *const left = expression->left;
7710                 if (!expression_has_effect(left)) {
7711                         warningf(&left->base.source_position,
7712                                  "left-hand operand of comma expression has no effect");
7713                 }
7714         }
7715         expression->base.type = expression->right->base.type;
7716 }
7717
7718 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr)  \
7719 static expression_t *parse_##binexpression_type(unsigned precedence,      \
7720                                                 expression_t *left)       \
7721 {                                                                         \
7722         expression_t *binexpr = allocate_expression_zero(binexpression_type); \
7723         binexpr->base.source_position = *HERE;                                \
7724         binexpr->binary.left          = left;                                 \
7725         eat(token_type);                                                      \
7726                                                                           \
7727         expression_t *right = parse_sub_expression(precedence + lr);          \
7728                                                                           \
7729         binexpr->binary.right = right;                                        \
7730         sfunc(&binexpr->binary);                                              \
7731                                                                           \
7732         return binexpr;                                                       \
7733 }
7734
7735 CREATE_BINEXPR_PARSER(',', EXPR_BINARY_COMMA,    semantic_comma, 1)
7736 CREATE_BINEXPR_PARSER('*', EXPR_BINARY_MUL,      semantic_binexpr_arithmetic, 1)
7737 CREATE_BINEXPR_PARSER('/', EXPR_BINARY_DIV,      semantic_binexpr_arithmetic, 1)
7738 CREATE_BINEXPR_PARSER('%', EXPR_BINARY_MOD,      semantic_binexpr_arithmetic, 1)
7739 CREATE_BINEXPR_PARSER('+', EXPR_BINARY_ADD,      semantic_add, 1)
7740 CREATE_BINEXPR_PARSER('-', EXPR_BINARY_SUB,      semantic_sub, 1)
7741 CREATE_BINEXPR_PARSER('<', EXPR_BINARY_LESS,     semantic_comparison, 1)
7742 CREATE_BINEXPR_PARSER('>', EXPR_BINARY_GREATER,  semantic_comparison, 1)
7743 CREATE_BINEXPR_PARSER('=', EXPR_BINARY_ASSIGN,   semantic_binexpr_assign, 0)
7744
7745 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,
7746                       semantic_comparison, 1)
7747 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,
7748                       semantic_comparison, 1)
7749 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,
7750                       semantic_comparison, 1)
7751 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,
7752                       semantic_comparison, 1)
7753
7754 CREATE_BINEXPR_PARSER('&', EXPR_BINARY_BITWISE_AND,
7755                       semantic_binexpr_arithmetic, 1)
7756 CREATE_BINEXPR_PARSER('|', EXPR_BINARY_BITWISE_OR,
7757                       semantic_binexpr_arithmetic, 1)
7758 CREATE_BINEXPR_PARSER('^', EXPR_BINARY_BITWISE_XOR,
7759                       semantic_binexpr_arithmetic, 1)
7760 CREATE_BINEXPR_PARSER(T_ANDAND, EXPR_BINARY_LOGICAL_AND,
7761                       semantic_logical_op, 1)
7762 CREATE_BINEXPR_PARSER(T_PIPEPIPE, EXPR_BINARY_LOGICAL_OR,
7763                       semantic_logical_op, 1)
7764 CREATE_BINEXPR_PARSER(T_LESSLESS, EXPR_BINARY_SHIFTLEFT,
7765                       semantic_shift_op, 1)
7766 CREATE_BINEXPR_PARSER(T_GREATERGREATER, EXPR_BINARY_SHIFTRIGHT,
7767                       semantic_shift_op, 1)
7768 CREATE_BINEXPR_PARSER(T_PLUSEQUAL, EXPR_BINARY_ADD_ASSIGN,
7769                       semantic_arithmetic_addsubb_assign, 0)
7770 CREATE_BINEXPR_PARSER(T_MINUSEQUAL, EXPR_BINARY_SUB_ASSIGN,
7771                       semantic_arithmetic_addsubb_assign, 0)
7772 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, EXPR_BINARY_MUL_ASSIGN,
7773                       semantic_arithmetic_assign, 0)
7774 CREATE_BINEXPR_PARSER(T_SLASHEQUAL, EXPR_BINARY_DIV_ASSIGN,
7775                       semantic_arithmetic_assign, 0)
7776 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, EXPR_BINARY_MOD_ASSIGN,
7777                       semantic_arithmetic_assign, 0)
7778 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, EXPR_BINARY_SHIFTLEFT_ASSIGN,
7779                       semantic_arithmetic_assign, 0)
7780 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, EXPR_BINARY_SHIFTRIGHT_ASSIGN,
7781                       semantic_arithmetic_assign, 0)
7782 CREATE_BINEXPR_PARSER(T_ANDEQUAL, EXPR_BINARY_BITWISE_AND_ASSIGN,
7783                       semantic_arithmetic_assign, 0)
7784 CREATE_BINEXPR_PARSER(T_PIPEEQUAL, EXPR_BINARY_BITWISE_OR_ASSIGN,
7785                       semantic_arithmetic_assign, 0)
7786 CREATE_BINEXPR_PARSER(T_CARETEQUAL, EXPR_BINARY_BITWISE_XOR_ASSIGN,
7787                       semantic_arithmetic_assign, 0)
7788
7789 static expression_t *parse_sub_expression(unsigned precedence)
7790 {
7791         if (token.type < 0) {
7792                 return expected_expression_error();
7793         }
7794
7795         expression_parser_function_t *parser
7796                 = &expression_parsers[token.type];
7797         source_position_t             source_position = token.source_position;
7798         expression_t                 *left;
7799
7800         if (parser->parser != NULL) {
7801                 left = parser->parser(parser->precedence);
7802         } else {
7803                 left = parse_primary_expression();
7804         }
7805         assert(left != NULL);
7806         left->base.source_position = source_position;
7807
7808         while(true) {
7809                 if (token.type < 0) {
7810                         return expected_expression_error();
7811                 }
7812
7813                 parser = &expression_parsers[token.type];
7814                 if (parser->infix_parser == NULL)
7815                         break;
7816                 if (parser->infix_precedence < precedence)
7817                         break;
7818
7819                 left = parser->infix_parser(parser->infix_precedence, left);
7820
7821                 assert(left != NULL);
7822                 assert(left->kind != EXPR_UNKNOWN);
7823                 left->base.source_position = source_position;
7824         }
7825
7826         return left;
7827 }
7828
7829 /**
7830  * Parse an expression.
7831  */
7832 static expression_t *parse_expression(void)
7833 {
7834         return parse_sub_expression(1);
7835 }
7836
7837 /**
7838  * Register a parser for a prefix-like operator with given precedence.
7839  *
7840  * @param parser      the parser function
7841  * @param token_type  the token type of the prefix token
7842  * @param precedence  the precedence of the operator
7843  */
7844 static void register_expression_parser(parse_expression_function parser,
7845                                        int token_type, unsigned precedence)
7846 {
7847         expression_parser_function_t *entry = &expression_parsers[token_type];
7848
7849         if (entry->parser != NULL) {
7850                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
7851                 panic("trying to register multiple expression parsers for a token");
7852         }
7853         entry->parser     = parser;
7854         entry->precedence = precedence;
7855 }
7856
7857 /**
7858  * Register a parser for an infix operator with given precedence.
7859  *
7860  * @param parser      the parser function
7861  * @param token_type  the token type of the infix operator
7862  * @param precedence  the precedence of the operator
7863  */
7864 static void register_infix_parser(parse_expression_infix_function parser,
7865                 int token_type, unsigned precedence)
7866 {
7867         expression_parser_function_t *entry = &expression_parsers[token_type];
7868
7869         if (entry->infix_parser != NULL) {
7870                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
7871                 panic("trying to register multiple infix expression parsers for a "
7872                       "token");
7873         }
7874         entry->infix_parser     = parser;
7875         entry->infix_precedence = precedence;
7876 }
7877
7878 /**
7879  * Initialize the expression parsers.
7880  */
7881 static void init_expression_parsers(void)
7882 {
7883         memset(&expression_parsers, 0, sizeof(expression_parsers));
7884
7885         register_infix_parser(parse_array_expression,         '[',              30);
7886         register_infix_parser(parse_call_expression,          '(',              30);
7887         register_infix_parser(parse_select_expression,        '.',              30);
7888         register_infix_parser(parse_select_expression,        T_MINUSGREATER,   30);
7889         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,
7890                                                               T_PLUSPLUS,       30);
7891         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,
7892                                                               T_MINUSMINUS,     30);
7893
7894         register_infix_parser(parse_EXPR_BINARY_MUL,          '*',              17);
7895         register_infix_parser(parse_EXPR_BINARY_DIV,          '/',              17);
7896         register_infix_parser(parse_EXPR_BINARY_MOD,          '%',              17);
7897         register_infix_parser(parse_EXPR_BINARY_ADD,          '+',              16);
7898         register_infix_parser(parse_EXPR_BINARY_SUB,          '-',              16);
7899         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,    T_LESSLESS,       15);
7900         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,   T_GREATERGREATER, 15);
7901         register_infix_parser(parse_EXPR_BINARY_LESS,         '<',              14);
7902         register_infix_parser(parse_EXPR_BINARY_GREATER,      '>',              14);
7903         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,    T_LESSEQUAL,      14);
7904         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL, T_GREATEREQUAL,   14);
7905         register_infix_parser(parse_EXPR_BINARY_EQUAL,        T_EQUALEQUAL,     13);
7906         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,
7907                                                     T_EXCLAMATIONMARKEQUAL, 13);
7908         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,  '&',              12);
7909         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,  '^',              11);
7910         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,   '|',              10);
7911         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,  T_ANDAND,          9);
7912         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,   T_PIPEPIPE,        8);
7913         register_infix_parser(parse_conditional_expression,   '?',               7);
7914         register_infix_parser(parse_EXPR_BINARY_ASSIGN,       '=',               2);
7915         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,   T_PLUSEQUAL,       2);
7916         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,   T_MINUSEQUAL,      2);
7917         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,   T_ASTERISKEQUAL,   2);
7918         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,   T_SLASHEQUAL,      2);
7919         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,   T_PERCENTEQUAL,    2);
7920         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,
7921                                                                 T_LESSLESSEQUAL, 2);
7922         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,
7923                                                           T_GREATERGREATEREQUAL, 2);
7924         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN,
7925                                                                      T_ANDEQUAL, 2);
7926         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,
7927                                                                     T_PIPEEQUAL, 2);
7928         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN,
7929                                                                    T_CARETEQUAL, 2);
7930
7931         register_infix_parser(parse_EXPR_BINARY_COMMA,        ',',               1);
7932
7933         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-',      25);
7934         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+',      25);
7935         register_expression_parser(parse_EXPR_UNARY_NOT,              '!',      25);
7936         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~',      25);
7937         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*',      25);
7938         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&',      25);
7939         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT,
7940                                                                   T_PLUSPLUS,   25);
7941         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT,
7942                                                                   T_MINUSMINUS, 25);
7943         register_expression_parser(parse_sizeof,                      T_sizeof, 25);
7944         register_expression_parser(parse_alignof,                T___alignof__, 25);
7945         register_expression_parser(parse_extension,            T___extension__, 25);
7946         register_expression_parser(parse_builtin_classify_type,
7947                                                      T___builtin_classify_type, 25);
7948 }
7949
7950 /**
7951  * Parse a asm statement arguments specification.
7952  */
7953 static asm_argument_t *parse_asm_arguments(bool is_out)
7954 {
7955         asm_argument_t *result = NULL;
7956         asm_argument_t *last   = NULL;
7957
7958         while (token.type == T_STRING_LITERAL || token.type == '[') {
7959                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
7960                 memset(argument, 0, sizeof(argument[0]));
7961
7962                 if (token.type == '[') {
7963                         eat('[');
7964                         if (token.type != T_IDENTIFIER) {
7965                                 parse_error_expected("while parsing asm argument",
7966                                                      T_IDENTIFIER, NULL);
7967                                 return NULL;
7968                         }
7969                         argument->symbol = token.v.symbol;
7970
7971                         expect(']');
7972                 }
7973
7974                 argument->constraints = parse_string_literals();
7975                 expect('(');
7976                 add_anchor_token(')');
7977                 expression_t *expression = parse_expression();
7978                 rem_anchor_token(')');
7979                 if (is_out) {
7980                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
7981                          * change size or type representation (e.g. int -> long is ok, but
7982                          * int -> float is not) */
7983                         if (expression->kind == EXPR_UNARY_CAST) {
7984                                 type_t      *const type = expression->base.type;
7985                                 type_kind_t  const kind = type->kind;
7986                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
7987                                         unsigned flags;
7988                                         unsigned size;
7989                                         if (kind == TYPE_ATOMIC) {
7990                                                 atomic_type_kind_t const akind = type->atomic.akind;
7991                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
7992                                                 size  = get_atomic_type_size(akind);
7993                                         } else {
7994                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
7995                                                 size  = get_atomic_type_size(get_intptr_kind());
7996                                         }
7997
7998                                         do {
7999                                                 expression_t *const value      = expression->unary.value;
8000                                                 type_t       *const value_type = value->base.type;
8001                                                 type_kind_t   const value_kind = value_type->kind;
8002
8003                                                 unsigned value_flags;
8004                                                 unsigned value_size;
8005                                                 if (value_kind == TYPE_ATOMIC) {
8006                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
8007                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8008                                                         value_size  = get_atomic_type_size(value_akind);
8009                                                 } else if (value_kind == TYPE_POINTER) {
8010                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8011                                                         value_size  = get_atomic_type_size(get_intptr_kind());
8012                                                 } else {
8013                                                         break;
8014                                                 }
8015
8016                                                 if (value_flags != flags || value_size != size)
8017                                                         break;
8018
8019                                                 expression = value;
8020                                         } while (expression->kind == EXPR_UNARY_CAST);
8021                                 }
8022                         }
8023
8024                         if (!is_lvalue(expression)) {
8025                                 errorf(&expression->base.source_position,
8026                                        "asm output argument is not an lvalue");
8027                         }
8028                 }
8029                 argument->expression = expression;
8030                 expect(')');
8031
8032                 set_address_taken(expression, true);
8033
8034                 if (last != NULL) {
8035                         last->next = argument;
8036                 } else {
8037                         result = argument;
8038                 }
8039                 last = argument;
8040
8041                 if (token.type != ',')
8042                         break;
8043                 eat(',');
8044         }
8045
8046         return result;
8047 end_error:
8048         return NULL;
8049 }
8050
8051 /**
8052  * Parse a asm statement clobber specification.
8053  */
8054 static asm_clobber_t *parse_asm_clobbers(void)
8055 {
8056         asm_clobber_t *result = NULL;
8057         asm_clobber_t *last   = NULL;
8058
8059         while(token.type == T_STRING_LITERAL) {
8060                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
8061                 clobber->clobber       = parse_string_literals();
8062
8063                 if (last != NULL) {
8064                         last->next = clobber;
8065                 } else {
8066                         result = clobber;
8067                 }
8068                 last = clobber;
8069
8070                 if (token.type != ',')
8071                         break;
8072                 eat(',');
8073         }
8074
8075         return result;
8076 }
8077
8078 /**
8079  * Parse an asm statement.
8080  */
8081 static statement_t *parse_asm_statement(void)
8082 {
8083         eat(T_asm);
8084
8085         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
8086         statement->base.source_position = token.source_position;
8087
8088         asm_statement_t *asm_statement = &statement->asms;
8089
8090         if (token.type == T_volatile) {
8091                 next_token();
8092                 asm_statement->is_volatile = true;
8093         }
8094
8095         expect('(');
8096         add_anchor_token(')');
8097         add_anchor_token(':');
8098         asm_statement->asm_text = parse_string_literals();
8099
8100         if (token.type != ':') {
8101                 rem_anchor_token(':');
8102                 goto end_of_asm;
8103         }
8104         eat(':');
8105
8106         asm_statement->outputs = parse_asm_arguments(true);
8107         if (token.type != ':') {
8108                 rem_anchor_token(':');
8109                 goto end_of_asm;
8110         }
8111         eat(':');
8112
8113         asm_statement->inputs = parse_asm_arguments(false);
8114         if (token.type != ':') {
8115                 rem_anchor_token(':');
8116                 goto end_of_asm;
8117         }
8118         rem_anchor_token(':');
8119         eat(':');
8120
8121         asm_statement->clobbers = parse_asm_clobbers();
8122
8123 end_of_asm:
8124         rem_anchor_token(')');
8125         expect(')');
8126         expect(';');
8127
8128         if (asm_statement->outputs == NULL) {
8129                 /* GCC: An 'asm' instruction without any output operands will be treated
8130                  * identically to a volatile 'asm' instruction. */
8131                 asm_statement->is_volatile = true;
8132         }
8133
8134         return statement;
8135 end_error:
8136         return create_invalid_statement();
8137 }
8138
8139 /**
8140  * Parse a case statement.
8141  */
8142 static statement_t *parse_case_statement(void)
8143 {
8144         eat(T_case);
8145
8146         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8147         source_position_t *const pos       = &statement->base.source_position;
8148
8149         *pos                             = token.source_position;
8150         statement->case_label.expression = parse_expression();
8151
8152         PUSH_PARENT(statement);
8153
8154         if (c_mode & _GNUC) {
8155                 if (token.type == T_DOTDOTDOT) {
8156                         next_token();
8157                         statement->case_label.end_range = parse_expression();
8158                 }
8159         }
8160
8161         expect(':');
8162
8163         if (! is_constant_expression(statement->case_label.expression)) {
8164                 errorf(pos, "case label does not reduce to an integer constant");
8165         } else if (current_switch != NULL) {
8166                 /* Check for duplicate case values */
8167                 /* FIXME slow */
8168                 long const val = fold_constant(statement->case_label.expression);
8169                 for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
8170                         expression_t const* const e = l->expression;
8171                         if (e == NULL || !is_constant_expression(e) || fold_constant(e) != val)
8172                                 continue;
8173
8174                         errorf(pos, "duplicate case value (previously used %P)",
8175                                &l->base.source_position);
8176                         break;
8177                 }
8178
8179                 /* link all cases into the switch statement */
8180                 if (current_switch->last_case == NULL) {
8181                         current_switch->first_case      = &statement->case_label;
8182                 } else {
8183                         current_switch->last_case->next = &statement->case_label;
8184                 }
8185                 current_switch->last_case = &statement->case_label;
8186         } else {
8187                 errorf(pos, "case label not within a switch statement");
8188         }
8189
8190         statement_t *const inner_stmt = parse_statement();
8191         statement->case_label.statement = inner_stmt;
8192         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8193                 errorf(&inner_stmt->base.source_position, "declaration after case label");
8194         }
8195
8196         POP_PARENT;
8197         return statement;
8198 end_error:
8199         POP_PARENT;
8200         return create_invalid_statement();
8201 }
8202
8203 /**
8204  * Finds an existing default label of a switch statement.
8205  */
8206 static case_label_statement_t *
8207 find_default_label(const switch_statement_t *statement)
8208 {
8209         case_label_statement_t *label = statement->first_case;
8210         for ( ; label != NULL; label = label->next) {
8211                 if (label->expression == NULL)
8212                         return label;
8213         }
8214         return NULL;
8215 }
8216
8217 /**
8218  * Parse a default statement.
8219  */
8220 static statement_t *parse_default_statement(void)
8221 {
8222         eat(T_default);
8223
8224         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8225         statement->base.source_position = token.source_position;
8226
8227         PUSH_PARENT(statement);
8228
8229         expect(':');
8230         if (current_switch != NULL) {
8231                 const case_label_statement_t *def_label = find_default_label(current_switch);
8232                 if (def_label != NULL) {
8233                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
8234                                &def_label->base.source_position);
8235                 } else {
8236                         /* link all cases into the switch statement */
8237                         if (current_switch->last_case == NULL) {
8238                                 current_switch->first_case      = &statement->case_label;
8239                         } else {
8240                                 current_switch->last_case->next = &statement->case_label;
8241                         }
8242                         current_switch->last_case = &statement->case_label;
8243                 }
8244         } else {
8245                 errorf(&statement->base.source_position,
8246                         "'default' label not within a switch statement");
8247         }
8248
8249         statement_t *const inner_stmt = parse_statement();
8250         statement->case_label.statement = inner_stmt;
8251         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8252                 errorf(&inner_stmt->base.source_position, "declaration after default label");
8253         }
8254
8255         POP_PARENT;
8256         return statement;
8257 end_error:
8258         POP_PARENT;
8259         return create_invalid_statement();
8260 }
8261
8262 /**
8263  * Return the declaration for a given label symbol or create a new one.
8264  *
8265  * @param symbol  the symbol of the label
8266  */
8267 static declaration_t *get_label(symbol_t *symbol)
8268 {
8269         declaration_t *candidate = get_declaration(symbol, NAMESPACE_LABEL);
8270         assert(current_function != NULL);
8271         /* if we found a label in the same function, then we already created the
8272          * declaration */
8273         if (candidate != NULL
8274                         && candidate->parent_scope == &current_function->scope) {
8275                 return candidate;
8276         }
8277
8278         /* otherwise we need to create a new one */
8279         declaration_t *const declaration = allocate_declaration_zero();
8280         declaration->namespc       = NAMESPACE_LABEL;
8281         declaration->symbol        = symbol;
8282
8283         label_push(declaration);
8284
8285         return declaration;
8286 }
8287
8288 /**
8289  * Parse a label statement.
8290  */
8291 static statement_t *parse_label_statement(void)
8292 {
8293         assert(token.type == T_IDENTIFIER);
8294         symbol_t *symbol = token.v.symbol;
8295         next_token();
8296
8297         declaration_t *label = get_label(symbol);
8298
8299         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
8300         statement->base.source_position = token.source_position;
8301         statement->label.label          = label;
8302
8303         PUSH_PARENT(statement);
8304
8305         /* if source position is already set then the label is defined twice,
8306          * otherwise it was just mentioned in a goto so far */
8307         if (label->source_position.input_name != NULL) {
8308                 errorf(HERE, "duplicate label '%Y' (declared %P)",
8309                        symbol, &label->source_position);
8310         } else {
8311                 label->source_position = token.source_position;
8312                 label->init.statement  = statement;
8313         }
8314
8315         eat(':');
8316
8317         if (token.type == '}') {
8318                 /* TODO only warn? */
8319                 if (false) {
8320                         warningf(HERE, "label at end of compound statement");
8321                         statement->label.statement = create_empty_statement();
8322                 } else {
8323                         errorf(HERE, "label at end of compound statement");
8324                         statement->label.statement = create_invalid_statement();
8325                 }
8326         } else if (token.type == ';') {
8327                 /* Eat an empty statement here, to avoid the warning about an empty
8328                  * statement after a label.  label:; is commonly used to have a label
8329                  * before a closing brace. */
8330                 statement->label.statement = create_empty_statement();
8331                 next_token();
8332         } else {
8333                 statement_t *const inner_stmt = parse_statement();
8334                 statement->label.statement = inner_stmt;
8335                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
8336                         errorf(&inner_stmt->base.source_position, "declaration after label");
8337                 }
8338         }
8339
8340         /* remember the labels in a list for later checking */
8341         if (label_last == NULL) {
8342                 label_first = &statement->label;
8343         } else {
8344                 label_last->next = &statement->label;
8345         }
8346         label_last = &statement->label;
8347
8348         POP_PARENT;
8349         return statement;
8350 }
8351
8352 /**
8353  * Parse an if statement.
8354  */
8355 static statement_t *parse_if(void)
8356 {
8357         eat(T_if);
8358
8359         statement_t *statement          = allocate_statement_zero(STATEMENT_IF);
8360         statement->base.source_position = token.source_position;
8361
8362         PUSH_PARENT(statement);
8363
8364         expect('(');
8365         add_anchor_token(')');
8366         statement->ifs.condition = parse_expression();
8367         rem_anchor_token(')');
8368         expect(')');
8369
8370         add_anchor_token(T_else);
8371         statement->ifs.true_statement = parse_statement();
8372         rem_anchor_token(T_else);
8373
8374         if (token.type == T_else) {
8375                 next_token();
8376                 statement->ifs.false_statement = parse_statement();
8377         }
8378
8379         POP_PARENT;
8380         return statement;
8381 end_error:
8382         POP_PARENT;
8383         return create_invalid_statement();
8384 }
8385
8386 /**
8387  * Parse a switch statement.
8388  */
8389 static statement_t *parse_switch(void)
8390 {
8391         eat(T_switch);
8392
8393         statement_t *statement          = allocate_statement_zero(STATEMENT_SWITCH);
8394         statement->base.source_position = token.source_position;
8395
8396         PUSH_PARENT(statement);
8397
8398         expect('(');
8399         expression_t *const expr = parse_expression();
8400         type_t       *      type = skip_typeref(expr->base.type);
8401         if (is_type_integer(type)) {
8402                 type = promote_integer(type);
8403         } else if (is_type_valid(type)) {
8404                 errorf(&expr->base.source_position,
8405                        "switch quantity is not an integer, but '%T'", type);
8406                 type = type_error_type;
8407         }
8408         statement->switchs.expression = create_implicit_cast(expr, type);
8409         expect(')');
8410
8411         switch_statement_t *rem = current_switch;
8412         current_switch          = &statement->switchs;
8413         statement->switchs.body = parse_statement();
8414         current_switch          = rem;
8415
8416         if (warning.switch_default &&
8417            find_default_label(&statement->switchs) == NULL) {
8418                 warningf(&statement->base.source_position, "switch has no default case");
8419         }
8420
8421         POP_PARENT;
8422         return statement;
8423 end_error:
8424         POP_PARENT;
8425         return create_invalid_statement();
8426 }
8427
8428 static statement_t *parse_loop_body(statement_t *const loop)
8429 {
8430         statement_t *const rem = current_loop;
8431         current_loop = loop;
8432
8433         statement_t *const body = parse_statement();
8434
8435         current_loop = rem;
8436         return body;
8437 }
8438
8439 /**
8440  * Parse a while statement.
8441  */
8442 static statement_t *parse_while(void)
8443 {
8444         eat(T_while);
8445
8446         statement_t *statement          = allocate_statement_zero(STATEMENT_WHILE);
8447         statement->base.source_position = token.source_position;
8448
8449         PUSH_PARENT(statement);
8450
8451         expect('(');
8452         add_anchor_token(')');
8453         statement->whiles.condition = parse_expression();
8454         rem_anchor_token(')');
8455         expect(')');
8456
8457         statement->whiles.body = parse_loop_body(statement);
8458
8459         POP_PARENT;
8460         return statement;
8461 end_error:
8462         POP_PARENT;
8463         return create_invalid_statement();
8464 }
8465
8466 /**
8467  * Parse a do statement.
8468  */
8469 static statement_t *parse_do(void)
8470 {
8471         eat(T_do);
8472
8473         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
8474         statement->base.source_position = token.source_position;
8475
8476         PUSH_PARENT(statement)
8477
8478         add_anchor_token(T_while);
8479         statement->do_while.body = parse_loop_body(statement);
8480         rem_anchor_token(T_while);
8481
8482         expect(T_while);
8483         expect('(');
8484         add_anchor_token(')');
8485         statement->do_while.condition = parse_expression();
8486         rem_anchor_token(')');
8487         expect(')');
8488         expect(';');
8489
8490         POP_PARENT;
8491         return statement;
8492 end_error:
8493         POP_PARENT;
8494         return create_invalid_statement();
8495 }
8496
8497 /**
8498  * Parse a for statement.
8499  */
8500 static statement_t *parse_for(void)
8501 {
8502         eat(T_for);
8503
8504         statement_t *statement          = allocate_statement_zero(STATEMENT_FOR);
8505         statement->base.source_position = token.source_position;
8506
8507         PUSH_PARENT(statement);
8508
8509         int      top        = environment_top();
8510         scope_t *last_scope = scope;
8511         set_scope(&statement->fors.scope);
8512
8513         expect('(');
8514         add_anchor_token(')');
8515
8516         if (token.type != ';') {
8517                 if (is_declaration_specifier(&token, false)) {
8518                         parse_declaration(record_declaration);
8519                 } else {
8520                         add_anchor_token(';');
8521                         expression_t *const init = parse_expression();
8522                         statement->fors.initialisation = init;
8523                         if (warning.unused_value && !expression_has_effect(init)) {
8524                                 warningf(&init->base.source_position,
8525                                          "initialisation of 'for'-statement has no effect");
8526                         }
8527                         rem_anchor_token(';');
8528                         expect(';');
8529                 }
8530         } else {
8531                 expect(';');
8532         }
8533
8534         if (token.type != ';') {
8535                 add_anchor_token(';');
8536                 statement->fors.condition = parse_expression();
8537                 rem_anchor_token(';');
8538         }
8539         expect(';');
8540         if (token.type != ')') {
8541                 expression_t *const step = parse_expression();
8542                 statement->fors.step = step;
8543                 if (warning.unused_value && !expression_has_effect(step)) {
8544                         warningf(&step->base.source_position,
8545                                  "step of 'for'-statement has no effect");
8546                 }
8547         }
8548         rem_anchor_token(')');
8549         expect(')');
8550         statement->fors.body = parse_loop_body(statement);
8551
8552         assert(scope == &statement->fors.scope);
8553         set_scope(last_scope);
8554         environment_pop_to(top);
8555
8556         POP_PARENT;
8557         return statement;
8558
8559 end_error:
8560         POP_PARENT;
8561         rem_anchor_token(')');
8562         assert(scope == &statement->fors.scope);
8563         set_scope(last_scope);
8564         environment_pop_to(top);
8565
8566         return create_invalid_statement();
8567 }
8568
8569 /**
8570  * Parse a goto statement.
8571  */
8572 static statement_t *parse_goto(void)
8573 {
8574         eat(T_goto);
8575
8576         if (token.type != T_IDENTIFIER) {
8577                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
8578                 eat_statement();
8579                 goto end_error;
8580         }
8581         symbol_t *symbol = token.v.symbol;
8582         next_token();
8583
8584         declaration_t *label = get_label(symbol);
8585
8586         statement_t *statement          = allocate_statement_zero(STATEMENT_GOTO);
8587         statement->base.source_position = token.source_position;
8588
8589         statement->gotos.label = label;
8590
8591         /* remember the goto's in a list for later checking */
8592         if (goto_last == NULL) {
8593                 goto_first = &statement->gotos;
8594         } else {
8595                 goto_last->next = &statement->gotos;
8596         }
8597         goto_last = &statement->gotos;
8598
8599         expect(';');
8600
8601         return statement;
8602 end_error:
8603         return create_invalid_statement();
8604 }
8605
8606 /**
8607  * Parse a continue statement.
8608  */
8609 static statement_t *parse_continue(void)
8610 {
8611         statement_t *statement;
8612         if (current_loop == NULL) {
8613                 errorf(HERE, "continue statement not within loop");
8614                 statement = create_invalid_statement();
8615         } else {
8616                 statement = allocate_statement_zero(STATEMENT_CONTINUE);
8617
8618                 statement->base.source_position = token.source_position;
8619         }
8620
8621         eat(T_continue);
8622         expect(';');
8623
8624         return statement;
8625 end_error:
8626         return create_invalid_statement();
8627 }
8628
8629 /**
8630  * Parse a break statement.
8631  */
8632 static statement_t *parse_break(void)
8633 {
8634         statement_t *statement;
8635         if (current_switch == NULL && current_loop == NULL) {
8636                 errorf(HERE, "break statement not within loop or switch");
8637                 statement = create_invalid_statement();
8638         } else {
8639                 statement = allocate_statement_zero(STATEMENT_BREAK);
8640
8641                 statement->base.source_position = token.source_position;
8642         }
8643
8644         eat(T_break);
8645         expect(';');
8646
8647         return statement;
8648 end_error:
8649         return create_invalid_statement();
8650 }
8651
8652 /**
8653  * Parse a __leave statement.
8654  */
8655 static statement_t *parse_leave(void)
8656 {
8657         statement_t *statement;
8658         if (current_try == NULL) {
8659                 errorf(HERE, "__leave statement not within __try");
8660                 statement = create_invalid_statement();
8661         } else {
8662                 statement = allocate_statement_zero(STATEMENT_LEAVE);
8663
8664                 statement->base.source_position = token.source_position;
8665         }
8666
8667         eat(T___leave);
8668         expect(';');
8669
8670         return statement;
8671 end_error:
8672         return create_invalid_statement();
8673 }
8674
8675 /**
8676  * Check if a given declaration represents a local variable.
8677  */
8678 static bool is_local_var_declaration(const declaration_t *declaration)
8679 {
8680         switch ((storage_class_tag_t) declaration->storage_class) {
8681         case STORAGE_CLASS_AUTO:
8682         case STORAGE_CLASS_REGISTER: {
8683                 const type_t *type = skip_typeref(declaration->type);
8684                 if (is_type_function(type)) {
8685                         return false;
8686                 } else {
8687                         return true;
8688                 }
8689         }
8690         default:
8691                 return false;
8692         }
8693 }
8694
8695 /**
8696  * Check if a given declaration represents a variable.
8697  */
8698 static bool is_var_declaration(const declaration_t *declaration)
8699 {
8700         if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
8701                 return false;
8702
8703         const type_t *type = skip_typeref(declaration->type);
8704         return !is_type_function(type);
8705 }
8706
8707 /**
8708  * Check if a given expression represents a local variable.
8709  */
8710 static bool is_local_variable(const expression_t *expression)
8711 {
8712         if (expression->base.kind != EXPR_REFERENCE) {
8713                 return false;
8714         }
8715         const declaration_t *declaration = expression->reference.declaration;
8716         return is_local_var_declaration(declaration);
8717 }
8718
8719 /**
8720  * Check if a given expression represents a local variable and
8721  * return its declaration then, else return NULL.
8722  */
8723 declaration_t *expr_is_variable(const expression_t *expression)
8724 {
8725         if (expression->base.kind != EXPR_REFERENCE) {
8726                 return NULL;
8727         }
8728         declaration_t *declaration = expression->reference.declaration;
8729         if (is_var_declaration(declaration))
8730                 return declaration;
8731         return NULL;
8732 }
8733
8734 /**
8735  * Parse a return statement.
8736  */
8737 static statement_t *parse_return(void)
8738 {
8739         statement_t *statement          = allocate_statement_zero(STATEMENT_RETURN);
8740         statement->base.source_position = token.source_position;
8741
8742         eat(T_return);
8743
8744         expression_t *return_value = NULL;
8745         if (token.type != ';') {
8746                 return_value = parse_expression();
8747         }
8748         expect(';');
8749
8750         const type_t *const func_type = current_function->type;
8751         assert(is_type_function(func_type));
8752         type_t *const return_type = skip_typeref(func_type->function.return_type);
8753
8754         if (return_value != NULL) {
8755                 type_t *return_value_type = skip_typeref(return_value->base.type);
8756
8757                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)
8758                                 && !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
8759                         warningf(&statement->base.source_position,
8760                                  "'return' with a value, in function returning void");
8761                         return_value = NULL;
8762                 } else {
8763                         assign_error_t error = semantic_assign(return_type, return_value);
8764                         report_assign_error(error, return_type, return_value, "'return'",
8765                                             &statement->base.source_position);
8766                         return_value = create_implicit_cast(return_value, return_type);
8767                 }
8768                 /* check for returning address of a local var */
8769                 if (return_value != NULL &&
8770                                 return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
8771                         const expression_t *expression = return_value->unary.value;
8772                         if (is_local_variable(expression)) {
8773                                 warningf(&statement->base.source_position,
8774                                          "function returns address of local variable");
8775                         }
8776                 }
8777         } else {
8778                 if (!is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
8779                         warningf(&statement->base.source_position,
8780                                  "'return' without value, in function returning non-void");
8781                 }
8782         }
8783         statement->returns.value = return_value;
8784
8785         return statement;
8786 end_error:
8787         return create_invalid_statement();
8788 }
8789
8790 /**
8791  * Parse a declaration statement.
8792  */
8793 static statement_t *parse_declaration_statement(void)
8794 {
8795         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
8796
8797         statement->base.source_position = token.source_position;
8798
8799         declaration_t *before = last_declaration;
8800         parse_declaration(record_declaration);
8801
8802         if (before == NULL) {
8803                 statement->declaration.declarations_begin = scope->declarations;
8804         } else {
8805                 statement->declaration.declarations_begin = before->next;
8806         }
8807         statement->declaration.declarations_end = last_declaration;
8808
8809         return statement;
8810 }
8811
8812 /**
8813  * Parse an expression statement, ie. expr ';'.
8814  */
8815 static statement_t *parse_expression_statement(void)
8816 {
8817         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
8818
8819         statement->base.source_position  = token.source_position;
8820         expression_t *const expr         = parse_expression();
8821         statement->expression.expression = expr;
8822
8823         expect(';');
8824
8825         return statement;
8826 end_error:
8827         return create_invalid_statement();
8828 }
8829
8830 /**
8831  * Parse a microsoft __try { } __finally { } or
8832  * __try{ } __except() { }
8833  */
8834 static statement_t *parse_ms_try_statment(void)
8835 {
8836         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
8837
8838         statement->base.source_position  = token.source_position;
8839         eat(T___try);
8840
8841         ms_try_statement_t *rem = current_try;
8842         current_try = &statement->ms_try;
8843         statement->ms_try.try_statement = parse_compound_statement(false);
8844         current_try = rem;
8845
8846         if (token.type == T___except) {
8847                 eat(T___except);
8848                 expect('(');
8849                 add_anchor_token(')');
8850                 expression_t *const expr = parse_expression();
8851                 type_t       *      type = skip_typeref(expr->base.type);
8852                 if (is_type_integer(type)) {
8853                         type = promote_integer(type);
8854                 } else if (is_type_valid(type)) {
8855                         errorf(&expr->base.source_position,
8856                                "__expect expression is not an integer, but '%T'", type);
8857                         type = type_error_type;
8858                 }
8859                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
8860                 rem_anchor_token(')');
8861                 expect(')');
8862                 statement->ms_try.final_statement = parse_compound_statement(false);
8863         } else if (token.type == T__finally) {
8864                 eat(T___finally);
8865                 statement->ms_try.final_statement = parse_compound_statement(false);
8866         } else {
8867                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
8868                 return create_invalid_statement();
8869         }
8870         return statement;
8871 end_error:
8872         return create_invalid_statement();
8873 }
8874
8875 static statement_t *parse_empty_statement(void)
8876 {
8877         if (warning.empty_statement) {
8878                 warningf(HERE, "statement is empty");
8879         }
8880         eat(';');
8881         return create_empty_statement();
8882 }
8883
8884 /**
8885  * Parse a statement.
8886  * There's also parse_statement() which additionally checks for
8887  * "statement has no effect" warnings
8888  */
8889 static statement_t *intern_parse_statement(void)
8890 {
8891         statement_t *statement = NULL;
8892
8893         /* declaration or statement */
8894         add_anchor_token(';');
8895         switch (token.type) {
8896         case T_IDENTIFIER:
8897                 if (look_ahead(1)->type == ':') {
8898                         statement = parse_label_statement();
8899                 } else if (is_typedef_symbol(token.v.symbol)) {
8900                         statement = parse_declaration_statement();
8901                 } else {
8902                         statement = parse_expression_statement();
8903                 }
8904                 break;
8905
8906         case T___extension__:
8907                 /* This can be a prefix to a declaration or an expression statement.
8908                  * We simply eat it now and parse the rest with tail recursion. */
8909                 do {
8910                         next_token();
8911                 } while (token.type == T___extension__);
8912                 statement = parse_statement();
8913                 break;
8914
8915         DECLARATION_START
8916                 statement = parse_declaration_statement();
8917                 break;
8918
8919         case ';':        statement = parse_empty_statement();         break;
8920         case '{':        statement = parse_compound_statement(false); break;
8921         case T___leave:  statement = parse_leave();                   break;
8922         case T___try:    statement = parse_ms_try_statment();         break;
8923         case T_asm:      statement = parse_asm_statement();           break;
8924         case T_break:    statement = parse_break();                   break;
8925         case T_case:     statement = parse_case_statement();          break;
8926         case T_continue: statement = parse_continue();                break;
8927         case T_default:  statement = parse_default_statement();       break;
8928         case T_do:       statement = parse_do();                      break;
8929         case T_for:      statement = parse_for();                     break;
8930         case T_goto:     statement = parse_goto();                    break;
8931         case T_if:       statement = parse_if ();                     break;
8932         case T_return:   statement = parse_return();                  break;
8933         case T_switch:   statement = parse_switch();                  break;
8934         case T_while:    statement = parse_while();                   break;
8935         default:         statement = parse_expression_statement();    break;
8936         }
8937         rem_anchor_token(';');
8938
8939         assert(statement != NULL
8940                         && statement->base.source_position.input_name != NULL);
8941
8942         return statement;
8943 }
8944
8945 /**
8946  * parse a statement and emits "statement has no effect" warning if needed
8947  * (This is really a wrapper around intern_parse_statement with check for 1
8948  *  single warning. It is needed, because for statement expressions we have
8949  *  to avoid the warning on the last statement)
8950  */
8951 static statement_t *parse_statement(void)
8952 {
8953         statement_t *statement = intern_parse_statement();
8954
8955         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
8956                 expression_t *expression = statement->expression.expression;
8957                 if (!expression_has_effect(expression)) {
8958                         warningf(&expression->base.source_position,
8959                                         "statement has no effect");
8960                 }
8961         }
8962
8963         return statement;
8964 }
8965
8966 /**
8967  * Parse a compound statement.
8968  */
8969 static statement_t *parse_compound_statement(bool inside_expression_statement)
8970 {
8971         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
8972         statement->base.source_position = token.source_position;
8973
8974         PUSH_PARENT(statement);
8975
8976         eat('{');
8977         add_anchor_token('}');
8978
8979         int      top        = environment_top();
8980         scope_t *last_scope = scope;
8981         set_scope(&statement->compound.scope);
8982
8983         statement_t *last_statement = NULL;
8984
8985         bool only_decls_so_far = true;
8986         while (token.type != '}' && token.type != T_EOF) {
8987                 statement_t *sub_statement = intern_parse_statement();
8988                 if (is_invalid_statement(sub_statement)) {
8989                         /* an error occurred. if we are at an anchor, return */
8990                         if (at_anchor())
8991                                 goto end_error;
8992                         continue;
8993                 }
8994
8995                 if (warning.declaration_after_statement) {
8996                         if (sub_statement->kind != STATEMENT_DECLARATION) {
8997                                 only_decls_so_far = false;
8998                         } else if (!only_decls_so_far) {
8999                                 warningf(&sub_statement->base.source_position,
9000                                          "ISO C90 forbids mixed declarations and code");
9001                         }
9002                 }
9003
9004                 if (last_statement != NULL) {
9005                         last_statement->base.next = sub_statement;
9006                 } else {
9007                         statement->compound.statements = sub_statement;
9008                 }
9009
9010                 while (sub_statement->base.next != NULL)
9011                         sub_statement = sub_statement->base.next;
9012
9013                 last_statement = sub_statement;
9014         }
9015
9016         if (token.type == '}') {
9017                 next_token();
9018         } else {
9019                 errorf(&statement->base.source_position,
9020                        "end of file while looking for closing '}'");
9021         }
9022
9023         /* look over all statements again to produce no effect warnings */
9024         if (warning.unused_value) {
9025                 statement_t *sub_statement = statement->compound.statements;
9026                 for( ; sub_statement != NULL; sub_statement = sub_statement->base.next) {
9027                         if (sub_statement->kind != STATEMENT_EXPRESSION)
9028                                 continue;
9029                         /* don't emit a warning for the last expression in an expression
9030                          * statement as it has always an effect */
9031                         if (inside_expression_statement && sub_statement->base.next == NULL)
9032                                 continue;
9033
9034                         expression_t *expression = sub_statement->expression.expression;
9035                         if (!expression_has_effect(expression)) {
9036                                 warningf(&expression->base.source_position,
9037                                          "statement has no effect");
9038                         }
9039                 }
9040         }
9041
9042 end_error:
9043         rem_anchor_token('}');
9044         assert(scope == &statement->compound.scope);
9045         set_scope(last_scope);
9046         environment_pop_to(top);
9047
9048         POP_PARENT;
9049         return statement;
9050 }
9051
9052 /**
9053  * Initialize builtin types.
9054  */
9055 static void initialize_builtin_types(void)
9056 {
9057         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
9058         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
9059         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
9060         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
9061         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
9062         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
9063         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    type_int);
9064         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
9065
9066         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
9067         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
9068         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
9069         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
9070 }
9071
9072 /**
9073  * Check for unused global static functions and variables
9074  */
9075 static void check_unused_globals(void)
9076 {
9077         if (!warning.unused_function && !warning.unused_variable)
9078                 return;
9079
9080         for (const declaration_t *decl = global_scope->declarations; decl != NULL; decl = decl->next) {
9081                 if (decl->used                  ||
9082                     decl->modifiers & DM_UNUSED ||
9083                     decl->modifiers & DM_USED   ||
9084                     decl->storage_class != STORAGE_CLASS_STATIC)
9085                         continue;
9086
9087                 type_t *const type = decl->type;
9088                 const char *s;
9089                 if (is_type_function(skip_typeref(type))) {
9090                         if (!warning.unused_function || decl->is_inline)
9091                                 continue;
9092
9093                         s = (decl->init.statement != NULL ? "defined" : "declared");
9094                 } else {
9095                         if (!warning.unused_variable)
9096                                 continue;
9097
9098                         s = "defined";
9099                 }
9100
9101                 warningf(&decl->source_position, "'%#T' %s but not used",
9102                         type, decl->symbol, s);
9103         }
9104 }
9105
9106 static void parse_global_asm(void)
9107 {
9108         eat(T_asm);
9109         expect('(');
9110
9111         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
9112         statement->base.source_position = token.source_position;
9113         statement->asms.asm_text        = parse_string_literals();
9114         statement->base.next            = unit->global_asm;
9115         unit->global_asm                = statement;
9116
9117         expect(')');
9118         expect(';');
9119
9120 end_error:;
9121 }
9122
9123 /**
9124  * Parse a translation unit.
9125  */
9126 static void parse_translation_unit(void)
9127 {
9128         for (;;) switch (token.type) {
9129                 DECLARATION_START
9130                 case T_IDENTIFIER:
9131                 case T___extension__:
9132                         parse_external_declaration();
9133                         break;
9134
9135                 case T_asm:
9136                         parse_global_asm();
9137                         break;
9138
9139                 case T_EOF:
9140                         return;
9141
9142                 case ';':
9143                         /* TODO error in strict mode */
9144                         warningf(HERE, "stray ';' outside of function");
9145                         next_token();
9146                         break;
9147
9148                 default:
9149                         errorf(HERE, "stray %K outside of function", &token);
9150                         if (token.type == '(' || token.type == '{' || token.type == '[')
9151                                 eat_until_matching_token(token.type);
9152                         next_token();
9153                         break;
9154         }
9155 }
9156
9157 /**
9158  * Parse the input.
9159  *
9160  * @return  the translation unit or NULL if errors occurred.
9161  */
9162 void start_parsing(void)
9163 {
9164         environment_stack = NEW_ARR_F(stack_entry_t, 0);
9165         label_stack       = NEW_ARR_F(stack_entry_t, 0);
9166         diagnostic_count  = 0;
9167         error_count       = 0;
9168         warning_count     = 0;
9169
9170         type_set_output(stderr);
9171         ast_set_output(stderr);
9172
9173         assert(unit == NULL);
9174         unit = allocate_ast_zero(sizeof(unit[0]));
9175
9176         assert(global_scope == NULL);
9177         global_scope = &unit->scope;
9178
9179         assert(scope == NULL);
9180         set_scope(&unit->scope);
9181
9182         initialize_builtin_types();
9183 }
9184
9185 translation_unit_t *finish_parsing(void)
9186 {
9187         assert(scope == &unit->scope);
9188         scope          = NULL;
9189         last_declaration = NULL;
9190
9191         assert(global_scope == &unit->scope);
9192         check_unused_globals();
9193         global_scope = NULL;
9194
9195         DEL_ARR_F(environment_stack);
9196         DEL_ARR_F(label_stack);
9197
9198         translation_unit_t *result = unit;
9199         unit = NULL;
9200         return result;
9201 }
9202
9203 void parse(void)
9204 {
9205         lookahead_bufpos = 0;
9206         for(int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
9207                 next_token();
9208         }
9209         parse_translation_unit();
9210 }
9211
9212 /**
9213  * Initialize the parser.
9214  */
9215 void init_parser(void)
9216 {
9217         if (c_mode & _MS) {
9218                 /* add predefined symbols for extended-decl-modifier */
9219                 sym_align      = symbol_table_insert("align");
9220                 sym_allocate   = symbol_table_insert("allocate");
9221                 sym_dllimport  = symbol_table_insert("dllimport");
9222                 sym_dllexport  = symbol_table_insert("dllexport");
9223                 sym_naked      = symbol_table_insert("naked");
9224                 sym_noinline   = symbol_table_insert("noinline");
9225                 sym_noreturn   = symbol_table_insert("noreturn");
9226                 sym_nothrow    = symbol_table_insert("nothrow");
9227                 sym_novtable   = symbol_table_insert("novtable");
9228                 sym_property   = symbol_table_insert("property");
9229                 sym_get        = symbol_table_insert("get");
9230                 sym_put        = symbol_table_insert("put");
9231                 sym_selectany  = symbol_table_insert("selectany");
9232                 sym_thread     = symbol_table_insert("thread");
9233                 sym_uuid       = symbol_table_insert("uuid");
9234                 sym_deprecated = symbol_table_insert("deprecated");
9235                 sym_restrict   = symbol_table_insert("restrict");
9236                 sym_noalias    = symbol_table_insert("noalias");
9237         }
9238         memset(token_anchor_set, 0, sizeof(token_anchor_set));
9239
9240         init_expression_parsers();
9241         obstack_init(&temp_obst);
9242
9243         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
9244         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
9245 }
9246
9247 /**
9248  * Terminate the parser.
9249  */
9250 void exit_parser(void)
9251 {
9252         obstack_free(&temp_obst, NULL);
9253 }