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 /** if wchar_t is equal to unsigned short. */
  43 bool opt_short_wchar_t =
  44 #ifdef _WIN32
  45         true;
  46 #else
  47         false;
  48 #endif
  49
  50 //#define PRINT_TOKENS
  51 #define MAX_LOOKAHEAD 2
  52
  53 typedef struct {
  54         declaration_t *old_declaration;
  55         symbol_t      *symbol;
  56         unsigned short namespc;
  57 } stack_entry_t;
  58
  59 typedef struct argument_list_t argument_list_t;
  60 struct argument_list_t {
  61         long              argument;
  62         argument_list_t  *next;
  63 };
  64
  65 typedef struct gnu_attribute_t gnu_attribute_t;
  66 struct gnu_attribute_t {
  67         gnu_attribute_kind_t kind;           /**< The kind of the GNU attribute. */
  68         gnu_attribute_t     *next;
  69         bool                 invalid;        /**< Set if this attribute had argument errors, */
  70         bool                 have_arguments; /**< True, if this attribute has arguments. */
  71         union {
  72                 size_t              value;
  73                 string_t            string;
  74                 atomic_type_kind_t  akind;
  75                 long                argument;  /**< Single argument. */
  76                 argument_list_t    *arguments; /**< List of argument expressions. */
  77         } u;
  78 };
  79
  80 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  81 struct declaration_specifiers_t {
  82         source_position_t  source_position;
  83         unsigned char      declared_storage_class;
  84         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  85         unsigned int       is_inline : 1;
  86         unsigned int       deprecated : 1;
  87         decl_modifiers_t   modifiers;         /**< declaration modifiers */
  88         gnu_attribute_t   *gnu_attributes;    /**< list of GNU attributes */
  89         const char        *deprecated_string; /**< can be set if declaration was marked deprecated. */
  90         symbol_t          *get_property_sym;  /**< the name of the get property if set. */
  91         symbol_t          *put_property_sym;  /**< the name of the put property if set. */
  92         type_t            *type;
  93 };
  94
  95 /**
  96  * An environment for parsing initializers (and compound literals).
  97  */
  98 typedef struct parse_initializer_env_t {
  99         type_t        *type;        /**< the type of the initializer. In case of an
 100                                          array type with unspecified size this gets
 101                                          adjusted to the actual size. */
 102         declaration_t *declaration; /**< the declaration that is initialized if any */
 103         bool           must_be_constant;
 104 } parse_initializer_env_t;
 105
 106 typedef declaration_t* (*parsed_declaration_func) (declaration_t *declaration, bool is_definition);
 107
 108 static token_t             token;
 109 static token_t             lookahead_buffer[MAX_LOOKAHEAD];
 110 static int                 lookahead_bufpos;
 111 static stack_entry_t      *environment_stack = NULL;
 112 static stack_entry_t      *label_stack       = NULL;
 113 static stack_entry_t      *local_label_stack = NULL;
 114 static scope_t            *global_scope      = NULL;
 115 static scope_t            *scope             = NULL;
 116 static declaration_t      *last_declaration  = NULL;
 117 static declaration_t      *current_function  = NULL;
 118 static declaration_t      *current_init_decl = NULL;
 119 static switch_statement_t *current_switch    = NULL;
 120 static statement_t        *current_loop      = NULL;
 121 static statement_t        *current_parent    = NULL;
 122 static ms_try_statement_t *current_try       = NULL;
 123 static goto_statement_t   *goto_first        = NULL;
 124 static goto_statement_t   *goto_last         = NULL;
 125 static label_statement_t  *label_first       = NULL;
 126 static label_statement_t  *label_last        = NULL;
 127 static translation_unit_t *unit              = NULL;
 128 static struct obstack      temp_obst;
 129
 130 #define PUSH_PARENT(stmt)                          \
 131         statement_t *const prev_parent = current_parent; \
 132         current_parent = (stmt);
 133 #define POP_PARENT ((void)(current_parent = prev_parent))
 134
 135 static source_position_t null_position = { NULL, 0 };
 136
 137 /** special symbol used for anonymous entities. */
 138 static const symbol_t *sym_anonymous = NULL;
 139
 140 /* symbols for Microsoft extended-decl-modifier */
 141 static const symbol_t *sym_align      = NULL;
 142 static const symbol_t *sym_allocate   = NULL;
 143 static const symbol_t *sym_dllimport  = NULL;
 144 static const symbol_t *sym_dllexport  = NULL;
 145 static const symbol_t *sym_naked      = NULL;
 146 static const symbol_t *sym_noinline   = NULL;
 147 static const symbol_t *sym_noreturn   = NULL;
 148 static const symbol_t *sym_nothrow    = NULL;
 149 static const symbol_t *sym_novtable   = NULL;
 150 static const symbol_t *sym_property   = NULL;
 151 static const symbol_t *sym_get        = NULL;
 152 static const symbol_t *sym_put        = NULL;
 153 static const symbol_t *sym_selectany  = NULL;
 154 static const symbol_t *sym_thread     = NULL;
 155 static const symbol_t *sym_uuid       = NULL;
 156 static const symbol_t *sym_deprecated = NULL;
 157 static const symbol_t *sym_restrict   = NULL;
 158 static const symbol_t *sym_noalias    = NULL;
 159
 160 /** The token anchor set */
 161 static unsigned char token_anchor_set[T_LAST_TOKEN];
 162
 163 /** The current source position. */
 164 #define HERE (&token.source_position)
 165
 166 static type_t *type_valist;
 167
 168 static statement_t *parse_compound_statement(bool inside_expression_statement);
 169 static statement_t *parse_statement(void);
 170
 171 static expression_t *parse_sub_expression(unsigned precedence);
 172 static expression_t *parse_expression(void);
 173 static type_t       *parse_typename(void);
 174
 175 static void parse_compound_type_entries(declaration_t *compound_declaration);
 176 static declaration_t *parse_declarator(
 177                 const declaration_specifiers_t *specifiers, bool may_be_abstract);
 178 static declaration_t *record_declaration(declaration_t *declaration, bool is_definition);
 179
 180 static void semantic_comparison(binary_expression_t *expression);
 181
 182 #define STORAGE_CLASSES     \
 183         case T_typedef:         \
 184         case T_extern:          \
 185         case T_static:          \
 186         case T_auto:            \
 187         case T_register:        \
 188         case T___thread:
 189
 190 #define TYPE_QUALIFIERS     \
 191         case T_const:           \
 192         case T_restrict:        \
 193         case T_volatile:        \
 194         case T_inline:          \
 195         case T__forceinline:    \
 196         case T___attribute__:
 197
 198 #ifdef PROVIDE_COMPLEX
 199 #define COMPLEX_SPECIFIERS  \
 200         case T__Complex:
 201 #define IMAGINARY_SPECIFIERS \
 202         case T__Imaginary:
 203 #else
 204 #define COMPLEX_SPECIFIERS
 205 #define IMAGINARY_SPECIFIERS
 206 #endif
 207
 208 #define TYPE_SPECIFIERS       \
 209         case T_void:              \
 210         case T_char:              \
 211         case T_short:             \
 212         case T_int:               \
 213         case T_long:              \
 214         case T_float:             \
 215         case T_double:            \
 216         case T_signed:            \
 217         case T_unsigned:          \
 218         case T__Bool:             \
 219         case T_struct:            \
 220         case T_union:             \
 221         case T_enum:              \
 222         case T___typeof__:        \
 223         case T___builtin_va_list: \
 224         case T__declspec:         \
 225         COMPLEX_SPECIFIERS        \
 226         IMAGINARY_SPECIFIERS
 227
 228 #define DECLARATION_START   \
 229         STORAGE_CLASSES         \
 230         TYPE_QUALIFIERS         \
 231         TYPE_SPECIFIERS
 232
 233 #define TYPENAME_START      \
 234         TYPE_QUALIFIERS         \
 235         TYPE_SPECIFIERS
 236
 237 /**
 238  * Allocate an AST node with given size and
 239  * initialize all fields with zero.
 240  */
 241 static void *allocate_ast_zero(size_t size)
 242 {
 243         void *res = allocate_ast(size);
 244         memset(res, 0, size);
 245         return res;
 246 }
 247
 248 static declaration_t *allocate_declaration_zero(void)
 249 {
 250         declaration_t *declaration = allocate_ast_zero(sizeof(declaration_t));
 251         declaration->type      = type_error_type;
 252         declaration->alignment = 0;
 253         return declaration;
 254 }
 255
 256 /**
 257  * Returns the size of a statement node.
 258  *
 259  * @param kind  the statement kind
 260  */
 261 static size_t get_statement_struct_size(statement_kind_t kind)
 262 {
 263         static const size_t sizes[] = {
 264                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 265                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 266                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 267                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 268                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 269                 [STATEMENT_IF]          = sizeof(if_statement_t),
 270                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 271                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 272                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 273                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 274                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 275                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 276                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 277                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 278                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 279                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 280                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 281                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 282                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 283         };
 284         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 285         assert(sizes[kind] != 0);
 286         return sizes[kind];
 287 }
 288
 289 /**
 290  * Returns the size of an expression node.
 291  *
 292  * @param kind  the expression kind
 293  */
 294 static size_t get_expression_struct_size(expression_kind_t kind)
 295 {
 296         static const size_t sizes[] = {
 297                 [EXPR_INVALID]                 = sizeof(expression_base_t),
 298                 [EXPR_REFERENCE]               = sizeof(reference_expression_t),
 299                 [EXPR_CONST]                   = sizeof(const_expression_t),
 300                 [EXPR_CHARACTER_CONSTANT]      = sizeof(const_expression_t),
 301                 [EXPR_WIDE_CHARACTER_CONSTANT] = sizeof(const_expression_t),
 302                 [EXPR_STRING_LITERAL]          = sizeof(string_literal_expression_t),
 303                 [EXPR_WIDE_STRING_LITERAL]     = sizeof(wide_string_literal_expression_t),
 304                 [EXPR_COMPOUND_LITERAL]        = sizeof(compound_literal_expression_t),
 305                 [EXPR_CALL]                    = sizeof(call_expression_t),
 306                 [EXPR_UNARY_FIRST]             = sizeof(unary_expression_t),
 307                 [EXPR_BINARY_FIRST]            = sizeof(binary_expression_t),
 308                 [EXPR_CONDITIONAL]             = sizeof(conditional_expression_t),
 309                 [EXPR_SELECT]                  = sizeof(select_expression_t),
 310                 [EXPR_ARRAY_ACCESS]            = sizeof(array_access_expression_t),
 311                 [EXPR_SIZEOF]                  = sizeof(typeprop_expression_t),
 312                 [EXPR_ALIGNOF]                 = sizeof(typeprop_expression_t),
 313                 [EXPR_CLASSIFY_TYPE]           = sizeof(classify_type_expression_t),
 314                 [EXPR_FUNCNAME]                = sizeof(funcname_expression_t),
 315                 [EXPR_BUILTIN_SYMBOL]          = sizeof(builtin_symbol_expression_t),
 316                 [EXPR_BUILTIN_CONSTANT_P]      = sizeof(builtin_constant_expression_t),
 317                 [EXPR_BUILTIN_PREFETCH]        = sizeof(builtin_prefetch_expression_t),
 318                 [EXPR_OFFSETOF]                = sizeof(offsetof_expression_t),
 319                 [EXPR_VA_START]                = sizeof(va_start_expression_t),
 320                 [EXPR_VA_ARG]                  = sizeof(va_arg_expression_t),
 321                 [EXPR_STATEMENT]               = sizeof(statement_expression_t),
 322                 [EXPR_LABEL_ADDRESS]           = sizeof(label_address_expression_t),
 323         };
 324         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 325                 return sizes[EXPR_UNARY_FIRST];
 326         }
 327         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 328                 return sizes[EXPR_BINARY_FIRST];
 329         }
 330         assert(kind <= sizeof(sizes) / sizeof(sizes[0]));
 331         assert(sizes[kind] != 0);
 332         return sizes[kind];
 333 }
 334
 335 /**
 336  * Allocate a statement node of given kind and initialize all
 337  * fields with zero.
 338  */
 339 static statement_t *allocate_statement_zero(statement_kind_t kind)
 340 {
 341         size_t       size = get_statement_struct_size(kind);
 342         statement_t *res  = allocate_ast_zero(size);
 343
 344         res->base.kind   = kind;
 345         res->base.parent = current_parent;
 346         return res;
 347 }
 348
 349 /**
 350  * Allocate an expression node of given kind and initialize all
 351  * fields with zero.
 352  */
 353 static expression_t *allocate_expression_zero(expression_kind_t kind)
 354 {
 355         size_t        size = get_expression_struct_size(kind);
 356         expression_t *res  = allocate_ast_zero(size);
 357
 358         res->base.kind = kind;
 359         res->base.type = type_error_type;
 360         return res;
 361 }
 362
 363 /**
 364  * Creates a new invalid expression.
 365  */
 366 static expression_t *create_invalid_expression(void)
 367 {
 368         expression_t *expression         = allocate_expression_zero(EXPR_INVALID);
 369         expression->base.source_position = token.source_position;
 370         return expression;
 371 }
 372
 373 /**
 374  * Creates a new invalid statement.
 375  */
 376 static statement_t *create_invalid_statement(void)
 377 {
 378         statement_t *statement          = allocate_statement_zero(STATEMENT_INVALID);
 379         statement->base.source_position = token.source_position;
 380         return statement;
 381 }
 382
 383 /**
 384  * Allocate a new empty statement.
 385  */
 386 static statement_t *create_empty_statement(void)
 387 {
 388         statement_t *statement          = allocate_statement_zero(STATEMENT_EMPTY);
 389         statement->base.source_position = token.source_position;
 390         return statement;
 391 }
 392
 393 /**
 394  * Returns the size of a type node.
 395  *
 396  * @param kind  the type kind
 397  */
 398 static size_t get_type_struct_size(type_kind_t kind)
 399 {
 400         static const size_t sizes[] = {
 401                 [TYPE_ATOMIC]          = sizeof(atomic_type_t),
 402                 [TYPE_COMPLEX]         = sizeof(complex_type_t),
 403                 [TYPE_IMAGINARY]       = sizeof(imaginary_type_t),
 404                 [TYPE_BITFIELD]        = sizeof(bitfield_type_t),
 405                 [TYPE_COMPOUND_STRUCT] = sizeof(compound_type_t),
 406                 [TYPE_COMPOUND_UNION]  = sizeof(compound_type_t),
 407                 [TYPE_ENUM]            = sizeof(enum_type_t),
 408                 [TYPE_FUNCTION]        = sizeof(function_type_t),
 409                 [TYPE_POINTER]         = sizeof(pointer_type_t),
 410                 [TYPE_ARRAY]           = sizeof(array_type_t),
 411                 [TYPE_BUILTIN]         = sizeof(builtin_type_t),
 412                 [TYPE_TYPEDEF]         = sizeof(typedef_type_t),
 413                 [TYPE_TYPEOF]          = sizeof(typeof_type_t),
 414         };
 415         assert(sizeof(sizes) / sizeof(sizes[0]) == (int) TYPE_TYPEOF + 1);
 416         assert(kind <= TYPE_TYPEOF);
 417         assert(sizes[kind] != 0);
 418         return sizes[kind];
 419 }
 420
 421 /**
 422  * Allocate a type node of given kind and initialize all
 423  * fields with zero.
 424  *
 425  * @param kind             type kind to allocate
 426  * @param source_position  the source position of the type definition
 427  */
 428 static type_t *allocate_type_zero(type_kind_t kind, const source_position_t *source_position)
 429 {
 430         size_t  size = get_type_struct_size(kind);
 431         type_t *res  = obstack_alloc(type_obst, size);
 432         memset(res, 0, size);
 433
 434         res->base.kind            = kind;
 435         res->base.source_position = *source_position;
 436         return res;
 437 }
 438
 439 /**
 440  * Returns the size of an initializer node.
 441  *
 442  * @param kind  the initializer kind
 443  */
 444 static size_t get_initializer_size(initializer_kind_t kind)
 445 {
 446         static const size_t sizes[] = {
 447                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 448                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 449                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 450                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 451                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 452         };
 453         assert(kind < sizeof(sizes) / sizeof(*sizes));
 454         assert(sizes[kind] != 0);
 455         return sizes[kind];
 456 }
 457
 458 /**
 459  * Allocate an initializer node of given kind and initialize all
 460  * fields with zero.
 461  */
 462 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 463 {
 464         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 465         result->kind          = kind;
 466
 467         return result;
 468 }
 469
 470 /**
 471  * Free a type from the type obstack.
 472  */
 473 static void free_type(void *type)
 474 {
 475         obstack_free(type_obst, type);
 476 }
 477
 478 /**
 479  * Returns the index of the top element of the environment stack.
 480  */
 481 static size_t environment_top(void)
 482 {
 483         return ARR_LEN(environment_stack);
 484 }
 485
 486 /**
 487  * Returns the index of the top element of the global label stack.
 488  */
 489 static size_t label_top(void)
 490 {
 491         return ARR_LEN(label_stack);
 492 }
 493
 494 /**
 495  * Returns the index of the top element of the local label stack.
 496  */
 497 static size_t local_label_top(void)
 498 {
 499         return ARR_LEN(local_label_stack);
 500 }
 501
 502 /**
 503  * Return the next token.
 504  */
 505 static inline void next_token(void)
 506 {
 507         token                              = lookahead_buffer[lookahead_bufpos];
 508         lookahead_buffer[lookahead_bufpos] = lexer_token;
 509         lexer_next_token();
 510
 511         lookahead_bufpos = (lookahead_bufpos+1) % MAX_LOOKAHEAD;
 512
 513 #ifdef PRINT_TOKENS
 514         print_token(stderr, &token);
 515         fprintf(stderr, "\n");
 516 #endif
 517 }
 518
 519 /**
 520  * Return the next token with a given lookahead.
 521  */
 522 static inline const token_t *look_ahead(int num)
 523 {
 524         assert(num > 0 && num <= MAX_LOOKAHEAD);
 525         int pos = (lookahead_bufpos+num-1) % MAX_LOOKAHEAD;
 526         return &lookahead_buffer[pos];
 527 }
 528
 529 /**
 530  * Adds a token to the token anchor set (a multi-set).
 531  */
 532 static void add_anchor_token(int token_type)
 533 {
 534         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 535         ++token_anchor_set[token_type];
 536 }
 537
 538 static int save_and_reset_anchor_state(int token_type)
 539 {
 540         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 541         int count = token_anchor_set[token_type];
 542         token_anchor_set[token_type] = 0;
 543         return count;
 544 }
 545
 546 static void restore_anchor_state(int token_type, int count)
 547 {
 548         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 549         token_anchor_set[token_type] = count;
 550 }
 551
 552 /**
 553  * Remove a token from the token anchor set (a multi-set).
 554  */
 555 static void rem_anchor_token(int token_type)
 556 {
 557         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 558         assert(token_anchor_set[token_type] != 0);
 559         --token_anchor_set[token_type];
 560 }
 561
 562 static bool at_anchor(void)
 563 {
 564         if (token.type < 0)
 565                 return false;
 566         return token_anchor_set[token.type];
 567 }
 568
 569 /**
 570  * Eat tokens until a matching token is found.
 571  */
 572 static void eat_until_matching_token(int type)
 573 {
 574         int end_token;
 575         switch (type) {
 576                 case '(': end_token = ')';  break;
 577                 case '{': end_token = '}';  break;
 578                 case '[': end_token = ']';  break;
 579                 default:  end_token = type; break;
 580         }
 581
 582         unsigned parenthesis_count = 0;
 583         unsigned brace_count       = 0;
 584         unsigned bracket_count     = 0;
 585         while (token.type        != end_token ||
 586                parenthesis_count != 0         ||
 587                brace_count       != 0         ||
 588                bracket_count     != 0) {
 589                 switch (token.type) {
 590                 case T_EOF: return;
 591                 case '(': ++parenthesis_count; break;
 592                 case '{': ++brace_count;       break;
 593                 case '[': ++bracket_count;     break;
 594
 595                 case ')':
 596                         if (parenthesis_count > 0)
 597                                 --parenthesis_count;
 598                         goto check_stop;
 599
 600                 case '}':
 601                         if (brace_count > 0)
 602                                 --brace_count;
 603                         goto check_stop;
 604
 605                 case ']':
 606                         if (bracket_count > 0)
 607                                 --bracket_count;
 608 check_stop:
 609                         if (token.type        == end_token &&
 610                             parenthesis_count == 0         &&
 611                             brace_count       == 0         &&
 612                             bracket_count     == 0)
 613                                 return;
 614                         break;
 615
 616                 default:
 617                         break;
 618                 }
 619                 next_token();
 620         }
 621 }
 622
 623 /**
 624  * Eat input tokens until an anchor is found.
 625  */
 626 static void eat_until_anchor(void)
 627 {
 628         if (token.type == T_EOF)
 629                 return;
 630         while (token_anchor_set[token.type] == 0) {
 631                 if (token.type == '(' || token.type == '{' || token.type == '[')
 632                         eat_until_matching_token(token.type);
 633                 if (token.type == T_EOF)
 634                         break;
 635                 next_token();
 636         }
 637 }
 638
 639 static void eat_block(void)
 640 {
 641         eat_until_matching_token('{');
 642         if (token.type == '}')
 643                 next_token();
 644 }
 645
 646 /**
 647  * eat all token until a ';' is reached or a stop token is found.
 648  */
 649 static void eat_statement(void)
 650 {
 651         eat_until_matching_token(';');
 652         if (token.type == ';')
 653                 next_token();
 654 }
 655
 656 #define eat(token_type)  do { assert(token.type == token_type); next_token(); } while (0)
 657
 658 /**
 659  * Report a parse error because an expected token was not found.
 660  */
 661 static
 662 #if defined __GNUC__ && __GNUC__ >= 4
 663 __attribute__((sentinel))
 664 #endif
 665 void parse_error_expected(const char *message, ...)
 666 {
 667         if (message != NULL) {
 668                 errorf(HERE, "%s", message);
 669         }
 670         va_list ap;
 671         va_start(ap, message);
 672         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 673         va_end(ap);
 674 }
 675
 676 /**
 677  * Report a type error.
 678  */
 679 static void type_error(const char *msg, const source_position_t *source_position,
 680                        type_t *type)
 681 {
 682         errorf(source_position, "%s, but found type '%T'", msg, type);
 683 }
 684
 685 /**
 686  * Report an incompatible type.
 687  */
 688 static void type_error_incompatible(const char *msg,
 689                 const source_position_t *source_position, type_t *type1, type_t *type2)
 690 {
 691         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 692                msg, type1, type2);
 693 }
 694
 695 /**
 696  * Expect the the current token is the expected token.
 697  * If not, generate an error, eat the current statement,
 698  * and goto the end_error label.
 699  */
 700 #define expect(expected)                                  \
 701         do {                                                  \
 702                 if (UNLIKELY(token.type != (expected))) {         \
 703                         parse_error_expected(NULL, (expected), NULL); \
 704                         add_anchor_token(expected);                   \
 705                         eat_until_anchor();                           \
 706                         if (token.type == expected)                   \
 707                                 next_token();                             \
 708                         rem_anchor_token(expected);                   \
 709                         goto end_error;                               \
 710                 }                                                 \
 711                 next_token();                                     \
 712         } while (0)
 713
 714 static void set_scope(scope_t *new_scope)
 715 {
 716         if (scope != NULL) {
 717                 scope->last_declaration = last_declaration;
 718         }
 719         scope = new_scope;
 720
 721         last_declaration = new_scope->last_declaration;
 722 }
 723
 724 /**
 725  * Search a symbol in a given namespace and returns its declaration or
 726  * NULL if this symbol was not found.
 727  */
 728 static declaration_t *get_declaration(const symbol_t *const symbol,
 729                                       const namespace_t namespc)
 730 {
 731         declaration_t *declaration = symbol->declaration;
 732         for( ; declaration != NULL; declaration = declaration->symbol_next) {
 733                 if (declaration->namespc == namespc)
 734                         return declaration;
 735         }
 736
 737         return NULL;
 738 }
 739
 740 /**
 741  * pushs an environment_entry on the environment stack and links the
 742  * corresponding symbol to the new entry
 743  */
 744 static void stack_push(stack_entry_t **stack_ptr, declaration_t *declaration)
 745 {
 746         symbol_t    *symbol  = declaration->symbol;
 747         namespace_t  namespc = (namespace_t) declaration->namespc;
 748
 749         /* replace/add declaration into declaration list of the symbol */
 750         declaration_t *iter = symbol->declaration;
 751         if (iter == NULL) {
 752                 symbol->declaration = declaration;
 753         } else {
 754                 declaration_t *iter_last = NULL;
 755                 for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 756                         /* replace an entry? */
 757                         if (iter->namespc == namespc) {
 758                                 if (iter_last == NULL) {
 759                                         symbol->declaration = declaration;
 760                                 } else {
 761                                         iter_last->symbol_next = declaration;
 762                                 }
 763                                 declaration->symbol_next = iter->symbol_next;
 764                                 break;
 765                         }
 766                 }
 767                 if (iter == NULL) {
 768                         assert(iter_last->symbol_next == NULL);
 769                         iter_last->symbol_next = declaration;
 770                 }
 771         }
 772
 773         /* remember old declaration */
 774         stack_entry_t entry;
 775         entry.symbol          = symbol;
 776         entry.old_declaration = iter;
 777         entry.namespc         = (unsigned short) namespc;
 778         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 779 }
 780
 781 /**
 782  * Push a declaration on the environment stack.
 783  *
 784  * @param declaration  the declaration
 785  */
 786 static void environment_push(declaration_t *declaration)
 787 {
 788         assert(declaration->source_position.input_name != NULL);
 789         assert(declaration->parent_scope != NULL);
 790         stack_push(&environment_stack, declaration);
 791 }
 792
 793 /**
 794  * Push a declaration on the global label stack.
 795  *
 796  * @param declaration  the declaration
 797  */
 798 static void label_push(declaration_t *declaration)
 799 {
 800         declaration->parent_scope = &current_function->scope;
 801         stack_push(&label_stack, declaration);
 802 }
 803
 804 /**
 805  * Push a declaration of the local label stack.
 806  *
 807  * @param declaration  the declaration
 808  */
 809 static void local_label_push(declaration_t *declaration)
 810 {
 811         assert(declaration->parent_scope != NULL);
 812         stack_push(&local_label_stack, declaration);
 813 }
 814
 815 /**
 816  * pops symbols from the environment stack until @p new_top is the top element
 817  */
 818 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 819 {
 820         stack_entry_t *stack = *stack_ptr;
 821         size_t         top   = ARR_LEN(stack);
 822         size_t         i;
 823
 824         assert(new_top <= top);
 825         if (new_top == top)
 826                 return;
 827
 828         for(i = top; i > new_top; --i) {
 829                 stack_entry_t *entry = &stack[i - 1];
 830
 831                 declaration_t *old_declaration = entry->old_declaration;
 832                 symbol_t      *symbol          = entry->symbol;
 833                 namespace_t    namespc         = (namespace_t)entry->namespc;
 834
 835                 /* replace/remove declaration */
 836                 declaration_t *declaration = symbol->declaration;
 837                 assert(declaration != NULL);
 838                 if (declaration->namespc == namespc) {
 839                         if (old_declaration == NULL) {
 840                                 symbol->declaration = declaration->symbol_next;
 841                         } else {
 842                                 symbol->declaration = old_declaration;
 843                         }
 844                 } else {
 845                         declaration_t *iter_last = declaration;
 846                         declaration_t *iter      = declaration->symbol_next;
 847                         for( ; iter != NULL; iter_last = iter, iter = iter->symbol_next) {
 848                                 /* replace an entry? */
 849                                 if (iter->namespc == namespc) {
 850                                         assert(iter_last != NULL);
 851                                         iter_last->symbol_next = old_declaration;
 852                                         if (old_declaration != NULL) {
 853                                                 old_declaration->symbol_next = iter->symbol_next;
 854                                         }
 855                                         break;
 856                                 }
 857                         }
 858                         assert(iter != NULL);
 859                 }
 860         }
 861
 862         ARR_SHRINKLEN(*stack_ptr, (int) new_top);
 863 }
 864
 865 /**
 866  * Pop all entries from the environment stack until the new_top
 867  * is reached.
 868  *
 869  * @param new_top  the new stack top
 870  */
 871 static void environment_pop_to(size_t new_top)
 872 {
 873         stack_pop_to(&environment_stack, new_top);
 874 }
 875
 876 /**
 877  * Pop all entries from the global label stack until the new_top
 878  * is reached.
 879  *
 880  * @param new_top  the new stack top
 881  */
 882 static void label_pop_to(size_t new_top)
 883 {
 884         stack_pop_to(&label_stack, new_top);
 885 }
 886
 887 /**
 888  * Pop all entries from the local label stack until the new_top
 889  * is reached.
 890  *
 891  * @param new_top  the new stack top
 892  */
 893 static void local_label_pop_to(size_t new_top)
 894 {
 895         stack_pop_to(&local_label_stack, new_top);
 896 }
 897
 898
 899 static int get_akind_rank(atomic_type_kind_t akind)
 900 {
 901         return (int) akind;
 902 }
 903
 904 static int get_rank(const type_t *type)
 905 {
 906         assert(!is_typeref(type));
 907         /* The C-standard allows promoting enums to int or unsigned int (see § 7.2.2
 908          * and esp. footnote 108). However we can't fold constants (yet), so we
 909          * can't decide whether unsigned int is possible, while int always works.
 910          * (unsigned int would be preferable when possible... for stuff like
 911          *  struct { enum { ... } bla : 4; } ) */
 912         if (type->kind == TYPE_ENUM)
 913                 return get_akind_rank(ATOMIC_TYPE_INT);
 914
 915         assert(type->kind == TYPE_ATOMIC);
 916         return get_akind_rank(type->atomic.akind);
 917 }
 918
 919 static type_t *promote_integer(type_t *type)
 920 {
 921         if (type->kind == TYPE_BITFIELD)
 922                 type = type->bitfield.base_type;
 923
 924         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
 925                 type = type_int;
 926
 927         return type;
 928 }
 929
 930 /**
 931  * Create a cast expression.
 932  *
 933  * @param expression  the expression to cast
 934  * @param dest_type   the destination type
 935  */
 936 static expression_t *create_cast_expression(expression_t *expression,
 937                                             type_t *dest_type)
 938 {
 939         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
 940
 941         cast->unary.value = expression;
 942         cast->base.type   = dest_type;
 943
 944         return cast;
 945 }
 946
 947 /**
 948  * Check if a given expression represents the 0 pointer constant.
 949  */
 950 static bool is_null_pointer_constant(const expression_t *expression)
 951 {
 952         /* skip void* cast */
 953         if (expression->kind == EXPR_UNARY_CAST
 954                         || expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
 955                 expression = expression->unary.value;
 956         }
 957
 958         /* TODO: not correct yet, should be any constant integer expression
 959          * which evaluates to 0 */
 960         if (expression->kind != EXPR_CONST)
 961                 return false;
 962
 963         type_t *const type = skip_typeref(expression->base.type);
 964         if (!is_type_integer(type))
 965                 return false;
 966
 967         return expression->conste.v.int_value == 0;
 968 }
 969
 970 /**
 971  * Create an implicit cast expression.
 972  *
 973  * @param expression  the expression to cast
 974  * @param dest_type   the destination type
 975  */
 976 static expression_t *create_implicit_cast(expression_t *expression,
 977                                           type_t *dest_type)
 978 {
 979         type_t *const source_type = expression->base.type;
 980
 981         if (source_type == dest_type)
 982                 return expression;
 983
 984         return create_cast_expression(expression, dest_type);
 985 }
 986
 987 typedef enum assign_error_t {
 988         ASSIGN_SUCCESS,
 989         ASSIGN_ERROR_INCOMPATIBLE,
 990         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
 991         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
 992         ASSIGN_WARNING_POINTER_FROM_INT,
 993         ASSIGN_WARNING_INT_FROM_POINTER
 994 } assign_error_t;
 995
 996 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
 997                                 const expression_t *const right,
 998                                 const char *context,
 999                                 const source_position_t *source_position)
1000 {
1001         type_t *const orig_type_right = right->base.type;
1002         type_t *const type_left       = skip_typeref(orig_type_left);
1003         type_t *const type_right      = skip_typeref(orig_type_right);
1004
1005         switch (error) {
1006         case ASSIGN_SUCCESS:
1007                 return;
1008         case ASSIGN_ERROR_INCOMPATIBLE:
1009                 errorf(source_position,
1010                        "destination type '%T' in %s is incompatible with type '%T'",
1011                        orig_type_left, context, orig_type_right);
1012                 return;
1013
1014         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
1015                 type_t *points_to_left
1016                         = skip_typeref(type_left->pointer.points_to);
1017                 type_t *points_to_right
1018                         = skip_typeref(type_right->pointer.points_to);
1019
1020                 /* the left type has all qualifiers from the right type */
1021                 unsigned missing_qualifiers
1022                         = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1023                 warningf(source_position,
1024                          "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
1025                          orig_type_left, context, orig_type_right, missing_qualifiers);
1026                 return;
1027         }
1028
1029         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
1030                 warningf(source_position,
1031                          "destination type '%T' in %s is incompatible with '%E' of type '%T'",
1032                                  orig_type_left, context, right, orig_type_right);
1033                 return;
1034
1035         case ASSIGN_WARNING_POINTER_FROM_INT:
1036                 warningf(source_position,
1037                          "%s makes pointer '%T' from integer '%T' without a cast",
1038                                  context, orig_type_left, orig_type_right);
1039                 return;
1040
1041         case ASSIGN_WARNING_INT_FROM_POINTER:
1042                 warningf(source_position,
1043                                 "%s makes integer '%T' from pointer '%T' without a cast",
1044                                 context, orig_type_left, orig_type_right);
1045                 return;
1046
1047         default:
1048                 panic("invalid error value");
1049         }
1050 }
1051
1052 /** Implements the rules from § 6.5.16.1 */
1053 static assign_error_t semantic_assign(type_t *orig_type_left,
1054                                       const expression_t *const right)
1055 {
1056         type_t *const orig_type_right = right->base.type;
1057         type_t *const type_left       = skip_typeref(orig_type_left);
1058         type_t *const type_right      = skip_typeref(orig_type_right);
1059
1060         if (is_type_pointer(type_left)) {
1061                 if (is_null_pointer_constant(right)) {
1062                         return ASSIGN_SUCCESS;
1063                 } else if (is_type_pointer(type_right)) {
1064                         type_t *points_to_left
1065                                 = skip_typeref(type_left->pointer.points_to);
1066                         type_t *points_to_right
1067                                 = skip_typeref(type_right->pointer.points_to);
1068                         assign_error_t res = ASSIGN_SUCCESS;
1069
1070                         /* the left type has all qualifiers from the right type */
1071                         unsigned missing_qualifiers
1072                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1073                         if (missing_qualifiers != 0) {
1074                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1075                         }
1076
1077                         points_to_left  = get_unqualified_type(points_to_left);
1078                         points_to_right = get_unqualified_type(points_to_right);
1079
1080                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID) ||
1081                                         is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1082                                 return res;
1083                         }
1084
1085                         if (!types_compatible(points_to_left, points_to_right)) {
1086                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1087                         }
1088
1089                         return res;
1090                 } else if (is_type_integer(type_right)) {
1091                         return ASSIGN_WARNING_POINTER_FROM_INT;
1092                 }
1093         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1094             (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1095                 && is_type_pointer(type_right))) {
1096                 return ASSIGN_SUCCESS;
1097         } else if ((is_type_compound(type_left)  && is_type_compound(type_right))
1098                         || (is_type_builtin(type_left) && is_type_builtin(type_right))) {
1099                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1100                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1101                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1102                         return ASSIGN_SUCCESS;
1103                 }
1104         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1105                 return ASSIGN_WARNING_INT_FROM_POINTER;
1106         }
1107
1108         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1109                 return ASSIGN_SUCCESS;
1110
1111         return ASSIGN_ERROR_INCOMPATIBLE;
1112 }
1113
1114 static expression_t *parse_constant_expression(void)
1115 {
1116         /* start parsing at precedence 7 (conditional expression) */
1117         expression_t *result = parse_sub_expression(7);
1118
1119         if (!is_constant_expression(result)) {
1120                 errorf(&result->base.source_position,
1121                        "expression '%E' is not constant\n", result);
1122         }
1123
1124         return result;
1125 }
1126
1127 static expression_t *parse_assignment_expression(void)
1128 {
1129         /* start parsing at precedence 2 (assignment expression) */
1130         return parse_sub_expression(2);
1131 }
1132
1133 static type_t *make_global_typedef(const char *name, type_t *type)
1134 {
1135         symbol_t *const symbol       = symbol_table_insert(name);
1136
1137         declaration_t *const declaration = allocate_declaration_zero();
1138         declaration->namespc                = NAMESPACE_NORMAL;
1139         declaration->storage_class          = STORAGE_CLASS_TYPEDEF;
1140         declaration->declared_storage_class = STORAGE_CLASS_TYPEDEF;
1141         declaration->type                   = type;
1142         declaration->symbol                 = symbol;
1143         declaration->source_position        = builtin_source_position;
1144         declaration->implicit               = true;
1145
1146         record_declaration(declaration, false);
1147
1148         type_t *typedef_type               = allocate_type_zero(TYPE_TYPEDEF, &builtin_source_position);
1149         typedef_type->typedeft.declaration = declaration;
1150
1151         return typedef_type;
1152 }
1153
1154 static string_t parse_string_literals(void)
1155 {
1156         assert(token.type == T_STRING_LITERAL);
1157         string_t result = token.v.string;
1158
1159         next_token();
1160
1161         while (token.type == T_STRING_LITERAL) {
1162                 result = concat_strings(&result, &token.v.string);
1163                 next_token();
1164         }
1165
1166         return result;
1167 }
1168
1169 static const char *const gnu_attribute_names[GNU_AK_LAST] = {
1170         [GNU_AK_CONST]                  = "const",
1171         [GNU_AK_VOLATILE]               = "volatile",
1172         [GNU_AK_CDECL]                  = "cdecl",
1173         [GNU_AK_STDCALL]                = "stdcall",
1174         [GNU_AK_FASTCALL]               = "fastcall",
1175         [GNU_AK_DEPRECATED]             = "deprecated",
1176         [GNU_AK_NOINLINE]               = "noinline",
1177         [GNU_AK_NORETURN]               = "noreturn",
1178         [GNU_AK_NAKED]                  = "naked",
1179         [GNU_AK_PURE]                   = "pure",
1180         [GNU_AK_ALWAYS_INLINE]          = "always_inline",
1181         [GNU_AK_MALLOC]                 = "malloc",
1182         [GNU_AK_WEAK]                   = "weak",
1183         [GNU_AK_CONSTRUCTOR]            = "constructor",
1184         [GNU_AK_DESTRUCTOR]             = "destructor",
1185         [GNU_AK_NOTHROW]                = "nothrow",
1186         [GNU_AK_TRANSPARENT_UNION]      = "transparent_union",
1187         [GNU_AK_COMMON]                 = "common",
1188         [GNU_AK_NOCOMMON]               = "nocommon",
1189         [GNU_AK_PACKED]                 = "packed",
1190         [GNU_AK_SHARED]                 = "shared",
1191         [GNU_AK_NOTSHARED]              = "notshared",
1192         [GNU_AK_USED]                   = "used",
1193         [GNU_AK_UNUSED]                 = "unused",
1194         [GNU_AK_NO_INSTRUMENT_FUNCTION] = "no_instrument_function",
1195         [GNU_AK_WARN_UNUSED_RESULT]     = "warn_unused_result",
1196         [GNU_AK_LONGCALL]               = "longcall",
1197         [GNU_AK_SHORTCALL]              = "shortcall",
1198         [GNU_AK_LONG_CALL]              = "long_call",
1199         [GNU_AK_SHORT_CALL]             = "short_call",
1200         [GNU_AK_FUNCTION_VECTOR]        = "function_vector",
1201         [GNU_AK_INTERRUPT]              = "interrupt",
1202         [GNU_AK_INTERRUPT_HANDLER]      = "interrupt_handler",
1203         [GNU_AK_NMI_HANDLER]            = "nmi_handler",
1204         [GNU_AK_NESTING]                = "nesting",
1205         [GNU_AK_NEAR]                   = "near",
1206         [GNU_AK_FAR]                    = "far",
1207         [GNU_AK_SIGNAL]                 = "signal",
1208         [GNU_AK_EIGTHBIT_DATA]          = "eightbit_data",
1209         [GNU_AK_TINY_DATA]              = "tiny_data",
1210         [GNU_AK_SAVEALL]                = "saveall",
1211         [GNU_AK_FLATTEN]                = "flatten",
1212         [GNU_AK_SSEREGPARM]             = "sseregparm",
1213         [GNU_AK_EXTERNALLY_VISIBLE]     = "externally_visible",
1214         [GNU_AK_RETURN_TWICE]           = "return_twice",
1215         [GNU_AK_MAY_ALIAS]              = "may_alias",
1216         [GNU_AK_MS_STRUCT]              = "ms_struct",
1217         [GNU_AK_GCC_STRUCT]             = "gcc_struct",
1218         [GNU_AK_DLLIMPORT]              = "dllimport",
1219         [GNU_AK_DLLEXPORT]              = "dllexport",
1220         [GNU_AK_ALIGNED]                = "aligned",
1221         [GNU_AK_ALIAS]                  = "alias",
1222         [GNU_AK_SECTION]                = "section",
1223         [GNU_AK_FORMAT]                 = "format",
1224         [GNU_AK_FORMAT_ARG]             = "format_arg",
1225         [GNU_AK_WEAKREF]                = "weakref",
1226         [GNU_AK_NONNULL]                = "nonnull",
1227         [GNU_AK_TLS_MODEL]              = "tls_model",
1228         [GNU_AK_VISIBILITY]             = "visibility",
1229         [GNU_AK_REGPARM]                = "regparm",
1230         [GNU_AK_MODE]                   = "mode",
1231         [GNU_AK_MODEL]                  = "model",
1232         [GNU_AK_TRAP_EXIT]              = "trap_exit",
1233         [GNU_AK_SP_SWITCH]              = "sp_switch",
1234         [GNU_AK_SENTINEL]               = "sentinel"
1235 };
1236
1237 /**
1238  * compare two string, ignoring double underscores on the second.
1239  */
1240 static int strcmp_underscore(const char *s1, const char *s2)
1241 {
1242         if (s2[0] == '_' && s2[1] == '_') {
1243                 size_t len2 = strlen(s2);
1244                 size_t len1 = strlen(s1);
1245                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1246                         return strncmp(s1, s2+2, len2-4);
1247                 }
1248         }
1249
1250         return strcmp(s1, s2);
1251 }
1252
1253 /**
1254  * Allocate a new gnu temporal attribute.
1255  */
1256 static gnu_attribute_t *allocate_gnu_attribute(gnu_attribute_kind_t kind)
1257 {
1258         gnu_attribute_t *attribute = obstack_alloc(&temp_obst, sizeof(*attribute));
1259         attribute->kind            = kind;
1260         attribute->next            = NULL;
1261         attribute->invalid         = false;
1262         attribute->have_arguments  = false;
1263
1264         return attribute;
1265 }
1266
1267 /**
1268  * parse one constant expression argument.
1269  */
1270 static void parse_gnu_attribute_const_arg(gnu_attribute_t *attribute)
1271 {
1272         expression_t *expression;
1273         add_anchor_token(')');
1274         expression = parse_constant_expression();
1275         rem_anchor_token(')');
1276         expect(')');
1277         attribute->u.argument = fold_constant(expression);
1278         return;
1279 end_error:
1280         attribute->invalid = true;
1281 }
1282
1283 /**
1284  * parse a list of constant expressions arguments.
1285  */
1286 static void parse_gnu_attribute_const_arg_list(gnu_attribute_t *attribute)
1287 {
1288         argument_list_t **list = &attribute->u.arguments;
1289         argument_list_t  *entry;
1290         expression_t     *expression;
1291         add_anchor_token(')');
1292         add_anchor_token(',');
1293         while (true) {
1294                 expression = parse_constant_expression();
1295                 entry = obstack_alloc(&temp_obst, sizeof(entry));
1296                 entry->argument = fold_constant(expression);
1297                 entry->next     = NULL;
1298                 *list = entry;
1299                 list = &entry->next;
1300                 if (token.type != ',')
1301                         break;
1302                 next_token();
1303         }
1304         rem_anchor_token(',');
1305         rem_anchor_token(')');
1306         expect(')');
1307         return;
1308 end_error:
1309         attribute->invalid = true;
1310 }
1311
1312 /**
1313  * parse one string literal argument.
1314  */
1315 static void parse_gnu_attribute_string_arg(gnu_attribute_t *attribute,
1316                                            string_t *string)
1317 {
1318         add_anchor_token('(');
1319         if (token.type != T_STRING_LITERAL) {
1320                 parse_error_expected("while parsing attribute directive",
1321                                      T_STRING_LITERAL, NULL);
1322                 goto end_error;
1323         }
1324         *string = parse_string_literals();
1325         rem_anchor_token('(');
1326         expect(')');
1327         return;
1328 end_error:
1329         attribute->invalid = true;
1330 }
1331
1332 /**
1333  * parse one tls model.
1334  */
1335 static void parse_gnu_attribute_tls_model_arg(gnu_attribute_t *attribute)
1336 {
1337         static const char *const tls_models[] = {
1338                 "global-dynamic",
1339                 "local-dynamic",
1340                 "initial-exec",
1341                 "local-exec"
1342         };
1343         string_t string = { NULL, 0 };
1344         parse_gnu_attribute_string_arg(attribute, &string);
1345         if (string.begin != NULL) {
1346                 for(size_t i = 0; i < 4; ++i) {
1347                         if (strcmp(tls_models[i], string.begin) == 0) {
1348                                 attribute->u.value = i;
1349                                 return;
1350                         }
1351                 }
1352                 errorf(HERE, "'%s' is an unrecognized tls model", string.begin);
1353         }
1354         attribute->invalid = true;
1355 }
1356
1357 /**
1358  * parse one tls model.
1359  */
1360 static void parse_gnu_attribute_visibility_arg(gnu_attribute_t *attribute)
1361 {
1362         static const char *const visibilities[] = {
1363                 "default",
1364                 "protected",
1365                 "hidden",
1366                 "internal"
1367         };
1368         string_t string = { NULL, 0 };
1369         parse_gnu_attribute_string_arg(attribute, &string);
1370         if (string.begin != NULL) {
1371                 for(size_t i = 0; i < 4; ++i) {
1372                         if (strcmp(visibilities[i], string.begin) == 0) {
1373                                 attribute->u.value = i;
1374                                 return;
1375                         }
1376                 }
1377                 errorf(HERE, "'%s' is an unrecognized visibility", string.begin);
1378         }
1379         attribute->invalid = true;
1380 }
1381
1382 /**
1383  * parse one (code) model.
1384  */
1385 static void parse_gnu_attribute_model_arg(gnu_attribute_t *attribute)
1386 {
1387         static const char *const visibilities[] = {
1388                 "small",
1389                 "medium",
1390                 "large"
1391         };
1392         string_t string = { NULL, 0 };
1393         parse_gnu_attribute_string_arg(attribute, &string);
1394         if (string.begin != NULL) {
1395                 for(int i = 0; i < 3; ++i) {
1396                         if (strcmp(visibilities[i], string.begin) == 0) {
1397                                 attribute->u.value = i;
1398                                 return;
1399                         }
1400                 }
1401                 errorf(HERE, "'%s' is an unrecognized model", string.begin);
1402         }
1403         attribute->invalid = true;
1404 }
1405
1406 static void parse_gnu_attribute_mode_arg(gnu_attribute_t *attribute)
1407 {
1408         /* TODO: find out what is allowed here... */
1409
1410         /* at least: byte, word, pointer, list of machine modes
1411          * __XXX___ is interpreted as XXX */
1412         add_anchor_token(')');
1413
1414         if (token.type != T_IDENTIFIER) {
1415                 expect(T_IDENTIFIER);
1416         }
1417
1418         /* This isn't really correct, the backend should provide a list of machine
1419          * specific modes (according to gcc philosophy that is...) */
1420         const char *symbol_str = token.v.symbol->string;
1421         if (strcmp_underscore("QI",   symbol_str) == 0 ||
1422             strcmp_underscore("byte", symbol_str) == 0) {
1423                 attribute->u.akind = ATOMIC_TYPE_CHAR;
1424         } else if (strcmp_underscore("HI", symbol_str) == 0) {
1425                 attribute->u.akind = ATOMIC_TYPE_SHORT;
1426         } else if (strcmp_underscore("SI",      symbol_str) == 0
1427                 || strcmp_underscore("word",    symbol_str) == 0
1428                 || strcmp_underscore("pointer", symbol_str) == 0) {
1429                 attribute->u.akind = ATOMIC_TYPE_INT;
1430         } else if (strcmp_underscore("DI", symbol_str) == 0) {
1431                 attribute->u.akind = ATOMIC_TYPE_LONGLONG;
1432         } else {
1433                 warningf(HERE, "ignoring unknown mode '%s'", symbol_str);
1434                 attribute->invalid = true;
1435         }
1436         next_token();
1437
1438         rem_anchor_token(')');
1439         expect(')');
1440         return;
1441 end_error:
1442         attribute->invalid = true;
1443 }
1444
1445 /**
1446  * parse one interrupt argument.
1447  */
1448 static void parse_gnu_attribute_interrupt_arg(gnu_attribute_t *attribute)
1449 {
1450         static const char *const interrupts[] = {
1451                 "IRQ",
1452                 "FIQ",
1453                 "SWI",
1454                 "ABORT",
1455                 "UNDEF"
1456         };
1457         string_t string = { NULL, 0 };
1458         parse_gnu_attribute_string_arg(attribute, &string);
1459         if (string.begin != NULL) {
1460                 for(size_t i = 0; i < 5; ++i) {
1461                         if (strcmp(interrupts[i], string.begin) == 0) {
1462                                 attribute->u.value = i;
1463                                 return;
1464                         }
1465                 }
1466                 errorf(HERE, "'%s' is not an interrupt", string.begin);
1467         }
1468         attribute->invalid = true;
1469 }
1470
1471 /**
1472  * parse ( identifier, const expression, const expression )
1473  */
1474 static void parse_gnu_attribute_format_args(gnu_attribute_t *attribute)
1475 {
1476         static const char *const format_names[] = {
1477                 "printf",
1478                 "scanf",
1479                 "strftime",
1480                 "strfmon"
1481         };
1482         int i;
1483
1484         if (token.type != T_IDENTIFIER) {
1485                 parse_error_expected("while parsing format attribute directive", T_IDENTIFIER, NULL);
1486                 goto end_error;
1487         }
1488         const char *name = token.v.symbol->string;
1489         for(i = 0; i < 4; ++i) {
1490                 if (strcmp_underscore(format_names[i], name) == 0)
1491                         break;
1492         }
1493         if (i >= 4) {
1494                 if (warning.attribute)
1495                         warningf(HERE, "'%s' is an unrecognized format function type", name);
1496         }
1497         next_token();
1498
1499         expect(',');
1500         add_anchor_token(')');
1501         add_anchor_token(',');
1502         parse_constant_expression();
1503         rem_anchor_token(',');
1504         rem_anchor_token(')');
1505
1506         expect(',');
1507         add_anchor_token(')');
1508         parse_constant_expression();
1509         rem_anchor_token(')');
1510         expect(')');
1511         return;
1512 end_error:
1513         attribute->u.value = true;
1514 }
1515
1516 static void check_no_argument(gnu_attribute_t *attribute, const char *name)
1517 {
1518         if (!attribute->have_arguments)
1519                 return;
1520
1521         /* should have no arguments */
1522         errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1523         eat_until_matching_token('(');
1524         /* we have already consumed '(', so we stop before ')', eat it */
1525         eat(')');
1526         attribute->invalid = true;
1527 }
1528
1529 /**
1530  * Parse one GNU attribute.
1531  *
1532  * Note that attribute names can be specified WITH or WITHOUT
1533  * double underscores, ie const or __const__.
1534  *
1535  * The following attributes are parsed without arguments
1536  *  const
1537  *  volatile
1538  *  cdecl
1539  *  stdcall
1540  *  fastcall
1541  *  deprecated
1542  *  noinline
1543  *  noreturn
1544  *  naked
1545  *  pure
1546  *  always_inline
1547  *  malloc
1548  *  weak
1549  *  constructor
1550  *  destructor
1551  *  nothrow
1552  *  transparent_union
1553  *  common
1554  *  nocommon
1555  *  packed
1556  *  shared
1557  *  notshared
1558  *  used
1559  *  unused
1560  *  no_instrument_function
1561  *  warn_unused_result
1562  *  longcall
1563  *  shortcall
1564  *  long_call
1565  *  short_call
1566  *  function_vector
1567  *  interrupt_handler
1568  *  nmi_handler
1569  *  nesting
1570  *  near
1571  *  far
1572  *  signal
1573  *  eightbit_data
1574  *  tiny_data
1575  *  saveall
1576  *  flatten
1577  *  sseregparm
1578  *  externally_visible
1579  *  return_twice
1580  *  may_alias
1581  *  ms_struct
1582  *  gcc_struct
1583  *  dllimport
1584  *  dllexport
1585  *
1586  * The following attributes are parsed with arguments
1587  *  aligned( const expression )
1588  *  alias( string literal )
1589  *  section( string literal )
1590  *  format( identifier, const expression, const expression )
1591  *  format_arg( const expression )
1592  *  tls_model( string literal )
1593  *  visibility( string literal )
1594  *  regparm( const expression )
1595  *  model( string leteral )
1596  *  trap_exit( const expression )
1597  *  sp_switch( string literal )
1598  *
1599  * The following attributes might have arguments
1600  *  weak_ref( string literal )
1601  *  non_null( const expression // ',' )
1602  *  interrupt( string literal )
1603  *  sentinel( constant expression )
1604  */
1605 static decl_modifiers_t parse_gnu_attribute(gnu_attribute_t **attributes)
1606 {
1607         gnu_attribute_t *head      = *attributes;
1608         gnu_attribute_t *last      = *attributes;
1609         decl_modifiers_t modifiers = 0;
1610         gnu_attribute_t *attribute;
1611
1612         eat(T___attribute__);
1613         expect('(');
1614         expect('(');
1615
1616         if (token.type != ')') {
1617                 /* find the end of the list */
1618                 if (last != NULL) {
1619                         while (last->next != NULL)
1620                                 last = last->next;
1621                 }
1622
1623                 /* non-empty attribute list */
1624                 while (true) {
1625                         const char *name;
1626                         if (token.type == T_const) {
1627                                 name = "const";
1628                         } else if (token.type == T_volatile) {
1629                                 name = "volatile";
1630                         } else if (token.type == T_cdecl) {
1631                                 /* __attribute__((cdecl)), WITH ms mode */
1632                                 name = "cdecl";
1633                         } else if (token.type == T_IDENTIFIER) {
1634                                 const symbol_t *sym = token.v.symbol;
1635                                 name = sym->string;
1636                         } else {
1637                                 parse_error_expected("while parsing GNU attribute", T_IDENTIFIER, NULL);
1638                                 break;
1639                         }
1640
1641                         next_token();
1642
1643                         int i;
1644                         for(i = 0; i < GNU_AK_LAST; ++i) {
1645                                 if (strcmp_underscore(gnu_attribute_names[i], name) == 0)
1646                                         break;
1647                         }
1648                         gnu_attribute_kind_t kind = (gnu_attribute_kind_t)i;
1649
1650                         attribute = NULL;
1651                         if (kind == GNU_AK_LAST) {
1652                                 if (warning.attribute)
1653                                         warningf(HERE, "'%s' attribute directive ignored", name);
1654
1655                                 /* skip possible arguments */
1656                                 if (token.type == '(') {
1657                                         eat_until_matching_token(')');
1658                                 }
1659                         } else {
1660                                 /* check for arguments */
1661                                 attribute = allocate_gnu_attribute(kind);
1662                                 if (token.type == '(') {
1663                                         next_token();
1664                                         if (token.type == ')') {
1665                                                 /* empty args are allowed */
1666                                                 next_token();
1667                                         } else
1668                                                 attribute->have_arguments = true;
1669                                 }
1670
1671                                 switch(kind) {
1672                                 case GNU_AK_CONST:
1673                                 case GNU_AK_VOLATILE:
1674                                 case GNU_AK_NAKED:
1675                                 case GNU_AK_MALLOC:
1676                                 case GNU_AK_WEAK:
1677                                 case GNU_AK_COMMON:
1678                                 case GNU_AK_NOCOMMON:
1679                                 case GNU_AK_SHARED:
1680                                 case GNU_AK_NOTSHARED:
1681                                 case GNU_AK_NO_INSTRUMENT_FUNCTION:
1682                                 case GNU_AK_WARN_UNUSED_RESULT:
1683                                 case GNU_AK_LONGCALL:
1684                                 case GNU_AK_SHORTCALL:
1685                                 case GNU_AK_LONG_CALL:
1686                                 case GNU_AK_SHORT_CALL:
1687                                 case GNU_AK_FUNCTION_VECTOR:
1688                                 case GNU_AK_INTERRUPT_HANDLER:
1689                                 case GNU_AK_NMI_HANDLER:
1690                                 case GNU_AK_NESTING:
1691                                 case GNU_AK_NEAR:
1692                                 case GNU_AK_FAR:
1693                                 case GNU_AK_SIGNAL:
1694                                 case GNU_AK_EIGTHBIT_DATA:
1695                                 case GNU_AK_TINY_DATA:
1696                                 case GNU_AK_SAVEALL:
1697                                 case GNU_AK_FLATTEN:
1698                                 case GNU_AK_SSEREGPARM:
1699                                 case GNU_AK_EXTERNALLY_VISIBLE:
1700                                 case GNU_AK_RETURN_TWICE:
1701                                 case GNU_AK_MAY_ALIAS:
1702                                 case GNU_AK_MS_STRUCT:
1703                                 case GNU_AK_GCC_STRUCT:
1704                                         goto no_arg;
1705
1706                                 case GNU_AK_CDECL:             modifiers |= DM_CDECL;             goto no_arg;
1707                                 case GNU_AK_FASTCALL:          modifiers |= DM_FASTCALL;          goto no_arg;
1708                                 case GNU_AK_STDCALL:           modifiers |= DM_STDCALL;           goto no_arg;
1709                                 case GNU_AK_UNUSED:            modifiers |= DM_UNUSED;            goto no_arg;
1710                                 case GNU_AK_USED:              modifiers |= DM_USED;              goto no_arg;
1711                                 case GNU_AK_PURE:              modifiers |= DM_PURE;              goto no_arg;
1712                                 case GNU_AK_ALWAYS_INLINE:     modifiers |= DM_FORCEINLINE;       goto no_arg;
1713                                 case GNU_AK_DLLIMPORT:         modifiers |= DM_DLLIMPORT;         goto no_arg;
1714                                 case GNU_AK_DLLEXPORT:         modifiers |= DM_DLLEXPORT;         goto no_arg;
1715                                 case GNU_AK_PACKED:            modifiers |= DM_PACKED;            goto no_arg;
1716                                 case GNU_AK_NOINLINE:          modifiers |= DM_NOINLINE;          goto no_arg;
1717                                 case GNU_AK_NORETURN:          modifiers |= DM_NORETURN;          goto no_arg;
1718                                 case GNU_AK_NOTHROW:           modifiers |= DM_NOTHROW;           goto no_arg;
1719                                 case GNU_AK_TRANSPARENT_UNION: modifiers |= DM_TRANSPARENT_UNION; goto no_arg;
1720                                 case GNU_AK_CONSTRUCTOR:       modifiers |= DM_CONSTRUCTOR;       goto no_arg;
1721                                 case GNU_AK_DESTRUCTOR:        modifiers |= DM_DESTRUCTOR;        goto no_arg;
1722                                 case GNU_AK_DEPRECATED:        modifiers |= DM_DEPRECATED;        goto no_arg;
1723
1724                                 case GNU_AK_ALIGNED:
1725                                         /* __align__ may be used without an argument */
1726                                         if (attribute->have_arguments) {
1727                                                 parse_gnu_attribute_const_arg(attribute);
1728                                         }
1729                                         break;
1730
1731                                 case GNU_AK_FORMAT_ARG:
1732                                 case GNU_AK_REGPARM:
1733                                 case GNU_AK_TRAP_EXIT:
1734                                         if (!attribute->have_arguments) {
1735                                                 /* should have arguments */
1736                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1737                                                 attribute->invalid = true;
1738                                         } else
1739                                                 parse_gnu_attribute_const_arg(attribute);
1740                                         break;
1741                                 case GNU_AK_ALIAS:
1742                                 case GNU_AK_SECTION:
1743                                 case GNU_AK_SP_SWITCH:
1744                                         if (!attribute->have_arguments) {
1745                                                 /* should have arguments */
1746                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1747                                                 attribute->invalid = true;
1748                                         } else
1749                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1750                                         break;
1751                                 case GNU_AK_FORMAT:
1752                                         if (!attribute->have_arguments) {
1753                                                 /* should have arguments */
1754                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1755                                                 attribute->invalid = true;
1756                                         } else
1757                                                 parse_gnu_attribute_format_args(attribute);
1758                                         break;
1759                                 case GNU_AK_WEAKREF:
1760                                         /* may have one string argument */
1761                                         if (attribute->have_arguments)
1762                                                 parse_gnu_attribute_string_arg(attribute, &attribute->u.string);
1763                                         break;
1764                                 case GNU_AK_NONNULL:
1765                                         if (attribute->have_arguments)
1766                                                 parse_gnu_attribute_const_arg_list(attribute);
1767                                         break;
1768                                 case GNU_AK_TLS_MODEL:
1769                                         if (!attribute->have_arguments) {
1770                                                 /* should have arguments */
1771                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1772                                         } else
1773                                                 parse_gnu_attribute_tls_model_arg(attribute);
1774                                         break;
1775                                 case GNU_AK_VISIBILITY:
1776                                         if (!attribute->have_arguments) {
1777                                                 /* should have arguments */
1778                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1779                                         } else
1780                                                 parse_gnu_attribute_visibility_arg(attribute);
1781                                         break;
1782                                 case GNU_AK_MODEL:
1783                                         if (!attribute->have_arguments) {
1784                                                 /* should have arguments */
1785                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1786                                         } else {
1787                                                 parse_gnu_attribute_model_arg(attribute);
1788                                         }
1789                                         break;
1790                                 case GNU_AK_MODE:
1791                                         if (!attribute->have_arguments) {
1792                                                 /* should have arguments */
1793                                                 errorf(HERE, "wrong number of arguments specified for '%s' attribute", name);
1794                                         } else {
1795                                                 parse_gnu_attribute_mode_arg(attribute);
1796                                         }
1797                                         break;
1798                                 case GNU_AK_INTERRUPT:
1799                                         /* may have one string argument */
1800                                         if (attribute->have_arguments)
1801                                                 parse_gnu_attribute_interrupt_arg(attribute);
1802                                         break;
1803                                 case GNU_AK_SENTINEL:
1804                                         /* may have one string argument */
1805                                         if (attribute->have_arguments)
1806                                                 parse_gnu_attribute_const_arg(attribute);
1807                                         break;
1808                                 case GNU_AK_LAST:
1809                                         /* already handled */
1810                                         break;
1811
1812 no_arg:
1813                                         check_no_argument(attribute, name);
1814                                 }
1815                         }
1816                         if (attribute != NULL) {
1817                                 if (last != NULL) {
1818                                         last->next = attribute;
1819                                         last       = attribute;
1820                                 } else {
1821                                         head = last = attribute;
1822                                 }
1823                         }
1824
1825                         if (token.type != ',')
1826                                 break;
1827                         next_token();
1828                 }
1829         }
1830         expect(')');
1831         expect(')');
1832 end_error:
1833         *attributes = head;
1834
1835         return modifiers;
1836 }
1837
1838 /**
1839  * Parse GNU attributes.
1840  */
1841 static decl_modifiers_t parse_attributes(gnu_attribute_t **attributes)
1842 {
1843         decl_modifiers_t modifiers = 0;
1844
1845         while (true) {
1846                 switch(token.type) {
1847                 case T___attribute__:
1848                         modifiers |= parse_gnu_attribute(attributes);
1849                         continue;
1850
1851                 case T_asm:
1852                         next_token();
1853                         expect('(');
1854                         if (token.type != T_STRING_LITERAL) {
1855                                 parse_error_expected("while parsing assembler attribute",
1856                                                      T_STRING_LITERAL, NULL);
1857                                 eat_until_matching_token('(');
1858                                 break;
1859                         } else {
1860                                 parse_string_literals();
1861                         }
1862                         expect(')');
1863                         continue;
1864
1865                 case T_cdecl:     modifiers |= DM_CDECL;    break;
1866                 case T__fastcall: modifiers |= DM_FASTCALL; break;
1867                 case T__stdcall:  modifiers |= DM_STDCALL;  break;
1868
1869                 case T___thiscall:
1870                         /* TODO record modifier */
1871                         warningf(HERE, "Ignoring declaration modifier %K", &token);
1872                         break;
1873
1874 end_error:
1875                 default: return modifiers;
1876                 }
1877
1878                 next_token();
1879         }
1880 }
1881
1882 static designator_t *parse_designation(void)
1883 {
1884         designator_t *result = NULL;
1885         designator_t *last   = NULL;
1886
1887         while (true) {
1888                 designator_t *designator;
1889                 switch(token.type) {
1890                 case '[':
1891                         designator = allocate_ast_zero(sizeof(designator[0]));
1892                         designator->source_position = token.source_position;
1893                         next_token();
1894                         add_anchor_token(']');
1895                         designator->array_index = parse_constant_expression();
1896                         rem_anchor_token(']');
1897                         expect(']');
1898                         break;
1899                 case '.':
1900                         designator = allocate_ast_zero(sizeof(designator[0]));
1901                         designator->source_position = token.source_position;
1902                         next_token();
1903                         if (token.type != T_IDENTIFIER) {
1904                                 parse_error_expected("while parsing designator",
1905                                                      T_IDENTIFIER, NULL);
1906                                 return NULL;
1907                         }
1908                         designator->symbol = token.v.symbol;
1909                         next_token();
1910                         break;
1911                 default:
1912                         expect('=');
1913                         return result;
1914                 }
1915
1916                 assert(designator != NULL);
1917                 if (last != NULL) {
1918                         last->next = designator;
1919                 } else {
1920                         result = designator;
1921                 }
1922                 last = designator;
1923         }
1924 end_error:
1925         return NULL;
1926 }
1927
1928 static initializer_t *initializer_from_string(array_type_t *type,
1929                                               const string_t *const string)
1930 {
1931         /* TODO: check len vs. size of array type */
1932         (void) type;
1933
1934         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
1935         initializer->string.string = *string;
1936
1937         return initializer;
1938 }
1939
1940 static initializer_t *initializer_from_wide_string(array_type_t *const type,
1941                                                    wide_string_t *const string)
1942 {
1943         /* TODO: check len vs. size of array type */
1944         (void) type;
1945
1946         initializer_t *const initializer =
1947                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
1948         initializer->wide_string.string = *string;
1949
1950         return initializer;
1951 }
1952
1953 /**
1954  * Build an initializer from a given expression.
1955  */
1956 static initializer_t *initializer_from_expression(type_t *orig_type,
1957                                                   expression_t *expression)
1958 {
1959         /* TODO check that expression is a constant expression */
1960
1961         /* § 6.7.8.14/15 char array may be initialized by string literals */
1962         type_t *type           = skip_typeref(orig_type);
1963         type_t *expr_type_orig = expression->base.type;
1964         type_t *expr_type      = skip_typeref(expr_type_orig);
1965         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
1966                 array_type_t *const array_type   = &type->array;
1967                 type_t       *const element_type = skip_typeref(array_type->element_type);
1968
1969                 if (element_type->kind == TYPE_ATOMIC) {
1970                         atomic_type_kind_t akind = element_type->atomic.akind;
1971                         switch (expression->kind) {
1972                                 case EXPR_STRING_LITERAL:
1973                                         if (akind == ATOMIC_TYPE_CHAR
1974                                                         || akind == ATOMIC_TYPE_SCHAR
1975                                                         || akind == ATOMIC_TYPE_UCHAR) {
1976                                                 return initializer_from_string(array_type,
1977                                                         &expression->string.value);
1978                                         }
1979
1980                                 case EXPR_WIDE_STRING_LITERAL: {
1981                                         type_t *bare_wchar_type = skip_typeref(type_wchar_t);
1982                                         if (get_unqualified_type(element_type) == bare_wchar_type) {
1983                                                 return initializer_from_wide_string(array_type,
1984                                                         &expression->wide_string.value);
1985                                         }
1986                                 }
1987
1988                                 default:
1989                                         break;
1990                         }
1991                 }
1992         }
1993
1994         assign_error_t error = semantic_assign(type, expression);
1995         if (error == ASSIGN_ERROR_INCOMPATIBLE)
1996                 return NULL;
1997         report_assign_error(error, type, expression, "initializer",
1998                             &expression->base.source_position);
1999
2000         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
2001         result->value.value = create_implicit_cast(expression, type);
2002
2003         return result;
2004 }
2005
2006 /**
2007  * Checks if a given expression can be used as an constant initializer.
2008  */
2009 static bool is_initializer_constant(const expression_t *expression)
2010 {
2011         return is_constant_expression(expression)
2012                 || is_address_constant(expression);
2013 }
2014
2015 /**
2016  * Parses an scalar initializer.
2017  *
2018  * § 6.7.8.11; eat {} without warning
2019  */
2020 static initializer_t *parse_scalar_initializer(type_t *type,
2021                                                bool must_be_constant)
2022 {
2023         /* there might be extra {} hierarchies */
2024         int braces = 0;
2025         if (token.type == '{') {
2026                 warningf(HERE, "extra curly braces around scalar initializer");
2027                 do {
2028                         ++braces;
2029                         next_token();
2030                 } while (token.type == '{');
2031         }
2032
2033         expression_t *expression = parse_assignment_expression();
2034         if (must_be_constant && !is_initializer_constant(expression)) {
2035                 errorf(&expression->base.source_position,
2036                        "Initialisation expression '%E' is not constant\n",
2037                        expression);
2038         }
2039
2040         initializer_t *initializer = initializer_from_expression(type, expression);
2041
2042         if (initializer == NULL) {
2043                 errorf(&expression->base.source_position,
2044                        "expression '%E' (type '%T') doesn't match expected type '%T'",
2045                        expression, expression->base.type, type);
2046                 /* TODO */
2047                 return NULL;
2048         }
2049
2050         bool additional_warning_displayed = false;
2051         while (braces > 0) {
2052                 if (token.type == ',') {
2053                         next_token();
2054                 }
2055                 if (token.type != '}') {
2056                         if (!additional_warning_displayed) {
2057                                 warningf(HERE, "additional elements in scalar initializer");
2058                                 additional_warning_displayed = true;
2059                         }
2060                 }
2061                 eat_block();
2062                 braces--;
2063         }
2064
2065         return initializer;
2066 }
2067
2068 /**
2069  * An entry in the type path.
2070  */
2071 typedef struct type_path_entry_t type_path_entry_t;
2072 struct type_path_entry_t {
2073         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
2074         union {
2075                 size_t         index;          /**< For array types: the current index. */
2076                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
2077         } v;
2078 };
2079
2080 /**
2081  * A type path expression a position inside compound or array types.
2082  */
2083 typedef struct type_path_t type_path_t;
2084 struct type_path_t {
2085         type_path_entry_t *path;         /**< An flexible array containing the current path. */
2086         type_t            *top_type;     /**< type of the element the path points */
2087         size_t             max_index;    /**< largest index in outermost array */
2088 };
2089
2090 /**
2091  * Prints a type path for debugging.
2092  */
2093 static __attribute__((unused)) void debug_print_type_path(
2094                 const type_path_t *path)
2095 {
2096         size_t len = ARR_LEN(path->path);
2097
2098         for(size_t i = 0; i < len; ++i) {
2099                 const type_path_entry_t *entry = & path->path[i];
2100
2101                 type_t *type = skip_typeref(entry->type);
2102                 if (is_type_compound(type)) {
2103                         /* in gcc mode structs can have no members */
2104                         if (entry->v.compound_entry == NULL) {
2105                                 assert(i == len-1);
2106                                 continue;
2107                         }
2108                         fprintf(stderr, ".%s", entry->v.compound_entry->symbol->string);
2109                 } else if (is_type_array(type)) {
2110                         fprintf(stderr, "[%zu]", entry->v.index);
2111                 } else {
2112                         fprintf(stderr, "-INVALID-");
2113                 }
2114         }
2115         if (path->top_type != NULL) {
2116                 fprintf(stderr, "  (");
2117                 print_type(path->top_type);
2118                 fprintf(stderr, ")");
2119         }
2120 }
2121
2122 /**
2123  * Return the top type path entry, ie. in a path
2124  * (type).a.b returns the b.
2125  */
2126 static type_path_entry_t *get_type_path_top(const type_path_t *path)
2127 {
2128         size_t len = ARR_LEN(path->path);
2129         assert(len > 0);
2130         return &path->path[len-1];
2131 }
2132
2133 /**
2134  * Enlarge the type path by an (empty) element.
2135  */
2136 static type_path_entry_t *append_to_type_path(type_path_t *path)
2137 {
2138         size_t len = ARR_LEN(path->path);
2139         ARR_RESIZE(type_path_entry_t, path->path, len+1);
2140
2141         type_path_entry_t *result = & path->path[len];
2142         memset(result, 0, sizeof(result[0]));
2143         return result;
2144 }
2145
2146 /**
2147  * Descending into a sub-type. Enter the scope of the current
2148  * top_type.
2149  */
2150 static void descend_into_subtype(type_path_t *path)
2151 {
2152         type_t *orig_top_type = path->top_type;
2153         type_t *top_type      = skip_typeref(orig_top_type);
2154
2155         type_path_entry_t *top = append_to_type_path(path);
2156         top->type              = top_type;
2157
2158         if (is_type_compound(top_type)) {
2159                 declaration_t *declaration = top_type->compound.declaration;
2160                 declaration_t *entry       = declaration->scope.declarations;
2161                 top->v.compound_entry      = entry;
2162
2163                 if (entry != NULL) {
2164                         path->top_type         = entry->type;
2165                 } else {
2166                         path->top_type         = NULL;
2167                 }
2168         } else if (is_type_array(top_type)) {
2169                 top->v.index   = 0;
2170                 path->top_type = top_type->array.element_type;
2171         } else {
2172                 assert(!is_type_valid(top_type));
2173         }
2174 }
2175
2176 /**
2177  * Pop an entry from the given type path, ie. returning from
2178  * (type).a.b to (type).a
2179  */
2180 static void ascend_from_subtype(type_path_t *path)
2181 {
2182         type_path_entry_t *top = get_type_path_top(path);
2183
2184         path->top_type = top->type;
2185
2186         size_t len = ARR_LEN(path->path);
2187         ARR_RESIZE(type_path_entry_t, path->path, len-1);
2188 }
2189
2190 /**
2191  * Pop entries from the given type path until the given
2192  * path level is reached.
2193  */
2194 static void ascend_to(type_path_t *path, size_t top_path_level)
2195 {
2196         size_t len = ARR_LEN(path->path);
2197
2198         while (len > top_path_level) {
2199                 ascend_from_subtype(path);
2200                 len = ARR_LEN(path->path);
2201         }
2202 }
2203
2204 static bool walk_designator(type_path_t *path, const designator_t *designator,
2205                             bool used_in_offsetof)
2206 {
2207         for( ; designator != NULL; designator = designator->next) {
2208                 type_path_entry_t *top       = get_type_path_top(path);
2209                 type_t            *orig_type = top->type;
2210
2211                 type_t *type = skip_typeref(orig_type);
2212
2213                 if (designator->symbol != NULL) {
2214                         symbol_t *symbol = designator->symbol;
2215                         if (!is_type_compound(type)) {
2216                                 if (is_type_valid(type)) {
2217                                         errorf(&designator->source_position,
2218                                                "'.%Y' designator used for non-compound type '%T'",
2219                                                symbol, orig_type);
2220                                 }
2221                                 goto failed;
2222                         }
2223
2224                         declaration_t *declaration = type->compound.declaration;
2225                         declaration_t *iter        = declaration->scope.declarations;
2226                         for( ; iter != NULL; iter = iter->next) {
2227                                 if (iter->symbol == symbol) {
2228                                         break;
2229                                 }
2230                         }
2231                         if (iter == NULL) {
2232                                 errorf(&designator->source_position,
2233                                        "'%T' has no member named '%Y'", orig_type, symbol);
2234                                 goto failed;
2235                         }
2236                         if (used_in_offsetof) {
2237                                 type_t *real_type = skip_typeref(iter->type);
2238                                 if (real_type->kind == TYPE_BITFIELD) {
2239                                         errorf(&designator->source_position,
2240                                                "offsetof designator '%Y' may not specify bitfield",
2241                                                symbol);
2242                                         goto failed;
2243                                 }
2244                         }
2245
2246                         top->type             = orig_type;
2247                         top->v.compound_entry = iter;
2248                         orig_type             = iter->type;
2249                 } else {
2250                         expression_t *array_index = designator->array_index;
2251                         assert(designator->array_index != NULL);
2252
2253                         if (!is_type_array(type)) {
2254                                 if (is_type_valid(type)) {
2255                                         errorf(&designator->source_position,
2256                                                "[%E] designator used for non-array type '%T'",
2257                                                array_index, orig_type);
2258                                 }
2259                                 goto failed;
2260                         }
2261                         if (!is_type_valid(array_index->base.type)) {
2262                                 goto failed;
2263                         }
2264
2265                         long index = fold_constant(array_index);
2266                         if (!used_in_offsetof) {
2267                                 if (index < 0) {
2268                                         errorf(&designator->source_position,
2269                                                "array index [%E] must be positive", array_index);
2270                                         goto failed;
2271                                 }
2272                                 if (type->array.size_constant == true) {
2273                                         long array_size = type->array.size;
2274                                         if (index >= array_size) {
2275                                                 errorf(&designator->source_position,
2276                                                        "designator [%E] (%d) exceeds array size %d",
2277                                                        array_index, index, array_size);
2278                                                 goto failed;
2279                                         }
2280                                 }
2281                         }
2282
2283                         top->type    = orig_type;
2284                         top->v.index = (size_t) index;
2285                         orig_type    = type->array.element_type;
2286                 }
2287                 path->top_type = orig_type;
2288
2289                 if (designator->next != NULL) {
2290                         descend_into_subtype(path);
2291                 }
2292         }
2293         return true;
2294
2295 failed:
2296         return false;
2297 }
2298
2299 static void advance_current_object(type_path_t *path, size_t top_path_level)
2300 {
2301         type_path_entry_t *top = get_type_path_top(path);
2302
2303         type_t *type = skip_typeref(top->type);
2304         if (is_type_union(type)) {
2305                 /* in unions only the first element is initialized */
2306                 top->v.compound_entry = NULL;
2307         } else if (is_type_struct(type)) {
2308                 declaration_t *entry = top->v.compound_entry;
2309
2310                 entry                 = entry->next;
2311                 top->v.compound_entry = entry;
2312                 if (entry != NULL) {
2313                         path->top_type = entry->type;
2314                         return;
2315                 }
2316         } else {
2317                 assert(is_type_array(type));
2318
2319                 top->v.index++;
2320
2321                 if (!type->array.size_constant || top->v.index < type->array.size) {
2322                         return;
2323                 }
2324         }
2325
2326         /* we're past the last member of the current sub-aggregate, try if we
2327          * can ascend in the type hierarchy and continue with another subobject */
2328         size_t len = ARR_LEN(path->path);
2329
2330         if (len > top_path_level) {
2331                 ascend_from_subtype(path);
2332                 advance_current_object(path, top_path_level);
2333         } else {
2334                 path->top_type = NULL;
2335         }
2336 }
2337
2338 /**
2339  * skip until token is found.
2340  */
2341 static void skip_until(int type)
2342 {
2343         while (token.type != type) {
2344                 if (token.type == T_EOF)
2345                         return;
2346                 next_token();
2347         }
2348 }
2349
2350 /**
2351  * skip any {...} blocks until a closing bracket is reached.
2352  */
2353 static void skip_initializers(void)
2354 {
2355         if (token.type == '{')
2356                 next_token();
2357
2358         while (token.type != '}') {
2359                 if (token.type == T_EOF)
2360                         return;
2361                 if (token.type == '{') {
2362                         eat_block();
2363                         continue;
2364                 }
2365                 next_token();
2366         }
2367 }
2368
2369 static initializer_t *create_empty_initializer(void)
2370 {
2371         static initializer_t empty_initializer
2372                 = { .list = { { INITIALIZER_LIST }, 0 } };
2373         return &empty_initializer;
2374 }
2375
2376 /**
2377  * Parse a part of an initialiser for a struct or union,
2378  */
2379 static initializer_t *parse_sub_initializer(type_path_t *path,
2380                 type_t *outer_type, size_t top_path_level,
2381                 parse_initializer_env_t *env)
2382 {
2383         if (token.type == '}') {
2384                 /* empty initializer */
2385                 return create_empty_initializer();
2386         }
2387
2388         type_t *orig_type = path->top_type;
2389         type_t *type      = NULL;
2390
2391         if (orig_type == NULL) {
2392                 /* We are initializing an empty compound. */
2393         } else {
2394                 type = skip_typeref(orig_type);
2395
2396                 /* we can't do usefull stuff if we didn't even parse the type. Skip the
2397                  * initializers in this case. */
2398                 if (!is_type_valid(type)) {
2399                         skip_initializers();
2400                         return create_empty_initializer();
2401                 }
2402         }
2403
2404         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2405
2406         while (true) {
2407                 designator_t *designator = NULL;
2408                 if (token.type == '.' || token.type == '[') {
2409                         designator = parse_designation();
2410                         goto finish_designator;
2411                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2412                         /* GNU-style designator ("identifier: value") */
2413                         designator = allocate_ast_zero(sizeof(designator[0]));
2414                         designator->source_position = token.source_position;
2415                         designator->symbol          = token.v.symbol;
2416                         eat(T_IDENTIFIER);
2417                         eat(':');
2418
2419 finish_designator:
2420                         /* reset path to toplevel, evaluate designator from there */
2421                         ascend_to(path, top_path_level);
2422                         if (!walk_designator(path, designator, false)) {
2423                                 /* can't continue after designation error */
2424                                 goto end_error;
2425                         }
2426
2427                         initializer_t *designator_initializer
2428                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2429                         designator_initializer->designator.designator = designator;
2430                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2431
2432                         orig_type = path->top_type;
2433                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2434                 }
2435
2436                 initializer_t *sub;
2437
2438                 if (token.type == '{') {
2439                         if (type != NULL && is_type_scalar(type)) {
2440                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2441                         } else {
2442                                 eat('{');
2443                                 if (type == NULL) {
2444                                         if (env->declaration != NULL) {
2445                                                 errorf(HERE, "extra brace group at end of initializer for '%Y'",
2446                                                        env->declaration->symbol);
2447                                         } else {
2448                                                 errorf(HERE, "extra brace group at end of initializer");
2449                                         }
2450                                 } else
2451                                         descend_into_subtype(path);
2452
2453                                 add_anchor_token('}');
2454                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2455                                                             env);
2456                                 rem_anchor_token('}');
2457
2458                                 if (type != NULL) {
2459                                         ascend_from_subtype(path);
2460                                         expect('}');
2461                                 } else {
2462                                         expect('}');
2463                                         goto error_parse_next;
2464                                 }
2465                         }
2466                 } else {
2467                         /* must be an expression */
2468                         expression_t *expression = parse_assignment_expression();
2469
2470                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2471                                 errorf(&expression->base.source_position,
2472                                        "Initialisation expression '%E' is not constant\n",
2473                                        expression);
2474                         }
2475
2476                         if (type == NULL) {
2477                                 /* we are already outside, ... */
2478                                 if (is_type_compound(outer_type) &&
2479                                     !outer_type->compound.declaration->init.complete) {
2480                                         goto error_parse_next;
2481                                 }
2482                                 goto error_excess;
2483                         }
2484
2485                         /* handle { "string" } special case */
2486                         if ((expression->kind == EXPR_STRING_LITERAL
2487                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2488                                         && outer_type != NULL) {
2489                                 sub = initializer_from_expression(outer_type, expression);
2490                                 if (sub != NULL) {
2491                                         if (token.type == ',') {
2492                                                 next_token();
2493                                         }
2494                                         if (token.type != '}') {
2495                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2496                                                                  orig_type);
2497                                         }
2498                                         /* TODO: eat , ... */
2499                                         return sub;
2500                                 }
2501                         }
2502
2503                         /* descend into subtypes until expression matches type */
2504                         while (true) {
2505                                 orig_type = path->top_type;
2506                                 type      = skip_typeref(orig_type);
2507
2508                                 sub = initializer_from_expression(orig_type, expression);
2509                                 if (sub != NULL) {
2510                                         break;
2511                                 }
2512                                 if (!is_type_valid(type)) {
2513                                         goto end_error;
2514                                 }
2515                                 if (is_type_scalar(type)) {
2516                                         errorf(&expression->base.source_position,
2517                                                         "expression '%E' doesn't match expected type '%T'",
2518                                                         expression, orig_type);
2519                                         goto end_error;
2520                                 }
2521
2522                                 descend_into_subtype(path);
2523                         }
2524                 }
2525
2526                 /* update largest index of top array */
2527                 const type_path_entry_t *first      = &path->path[0];
2528                 type_t                  *first_type = first->type;
2529                 first_type                          = skip_typeref(first_type);
2530                 if (is_type_array(first_type)) {
2531                         size_t index = first->v.index;
2532                         if (index > path->max_index)
2533                                 path->max_index = index;
2534                 }
2535
2536                 if (type != NULL) {
2537                         /* append to initializers list */
2538                         ARR_APP1(initializer_t*, initializers, sub);
2539                 } else {
2540 error_excess:
2541                         if (env->declaration != NULL)
2542                                 warningf(HERE, "excess elements in struct initializer for '%Y'",
2543                                  env->declaration->symbol);
2544                         else
2545                                 warningf(HERE, "excess elements in struct initializer");
2546                 }
2547
2548 error_parse_next:
2549                 if (token.type == '}') {
2550                         break;
2551                 }
2552                 expect(',');
2553                 if (token.type == '}') {
2554                         break;
2555                 }
2556
2557                 if (type != NULL) {
2558                         /* advance to the next declaration if we are not at the end */
2559                         advance_current_object(path, top_path_level);
2560                         orig_type = path->top_type;
2561                         if (orig_type != NULL)
2562                                 type = skip_typeref(orig_type);
2563                         else
2564                                 type = NULL;
2565                 }
2566         }
2567
2568         size_t len  = ARR_LEN(initializers);
2569         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2570         initializer_t *result = allocate_ast_zero(size);
2571         result->kind          = INITIALIZER_LIST;
2572         result->list.len      = len;
2573         memcpy(&result->list.initializers, initializers,
2574                len * sizeof(initializers[0]));
2575
2576         DEL_ARR_F(initializers);
2577         ascend_to(path, top_path_level+1);
2578
2579         return result;
2580
2581 end_error:
2582         skip_initializers();
2583         DEL_ARR_F(initializers);
2584         ascend_to(path, top_path_level+1);
2585         return NULL;
2586 }
2587
2588 /**
2589  * Parses an initializer. Parsers either a compound literal
2590  * (env->declaration == NULL) or an initializer of a declaration.
2591  */
2592 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2593 {
2594         type_t        *type   = skip_typeref(env->type);
2595         initializer_t *result = NULL;
2596         size_t         max_index;
2597
2598         if (is_type_scalar(type)) {
2599                 result = parse_scalar_initializer(type, env->must_be_constant);
2600         } else if (token.type == '{') {
2601                 eat('{');
2602
2603                 type_path_t path;
2604                 memset(&path, 0, sizeof(path));
2605                 path.top_type = env->type;
2606                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2607
2608                 descend_into_subtype(&path);
2609
2610                 add_anchor_token('}');
2611                 result = parse_sub_initializer(&path, env->type, 1, env);
2612                 rem_anchor_token('}');
2613
2614                 max_index = path.max_index;
2615                 DEL_ARR_F(path.path);
2616
2617                 expect('}');
2618         } else {
2619                 /* parse_scalar_initializer() also works in this case: we simply
2620                  * have an expression without {} around it */
2621                 result = parse_scalar_initializer(type, env->must_be_constant);
2622         }
2623
2624         /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
2625          * the array type size */
2626         if (is_type_array(type) && type->array.size_expression == NULL
2627                         && result != NULL) {
2628                 size_t size;
2629                 switch (result->kind) {
2630                 case INITIALIZER_LIST:
2631                         size = max_index + 1;
2632                         break;
2633
2634                 case INITIALIZER_STRING:
2635                         size = result->string.string.size;
2636                         break;
2637
2638                 case INITIALIZER_WIDE_STRING:
2639                         size = result->wide_string.string.size;
2640                         break;
2641
2642                 case INITIALIZER_DESIGNATOR:
2643                 case INITIALIZER_VALUE:
2644                         /* can happen for parse errors */
2645                         size = 0;
2646                         break;
2647
2648                 default:
2649                         internal_errorf(HERE, "invalid initializer type");
2650                 }
2651
2652                 expression_t *cnst       = allocate_expression_zero(EXPR_CONST);
2653                 cnst->base.type          = type_size_t;
2654                 cnst->conste.v.int_value = size;
2655
2656                 type_t *new_type = duplicate_type(type);
2657
2658                 new_type->array.size_expression = cnst;
2659                 new_type->array.size_constant   = true;
2660                 new_type->array.size            = size;
2661                 env->type = new_type;
2662         }
2663
2664         return result;
2665 end_error:
2666         return NULL;
2667 }
2668
2669 static declaration_t *append_declaration(declaration_t *declaration);
2670
2671 static declaration_t *parse_compound_type_specifier(bool is_struct)
2672 {
2673         gnu_attribute_t  *attributes = NULL;
2674         decl_modifiers_t  modifiers  = 0;
2675         if (is_struct) {
2676                 eat(T_struct);
2677         } else {
2678                 eat(T_union);
2679         }
2680
2681         symbol_t      *symbol      = NULL;
2682         declaration_t *declaration = NULL;
2683
2684         if (token.type == T___attribute__) {
2685                 modifiers |= parse_attributes(&attributes);
2686         }
2687
2688         if (token.type == T_IDENTIFIER) {
2689                 symbol = token.v.symbol;
2690                 next_token();
2691
2692                 namespace_t const namespc =
2693                         is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION;
2694                 declaration = get_declaration(symbol, namespc);
2695                 if (declaration != NULL) {
2696                         if (declaration->parent_scope != scope &&
2697                             (token.type == '{' || token.type == ';')) {
2698                                 declaration = NULL;
2699                         } else if (declaration->init.complete &&
2700                                    token.type == '{') {
2701                                 assert(symbol != NULL);
2702                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition at %P)",
2703                                        is_struct ? "struct" : "union", symbol,
2704                                        &declaration->source_position);
2705                                 declaration->scope.declarations = NULL;
2706                         }
2707                 }
2708         } else if (token.type != '{') {
2709                 if (is_struct) {
2710                         parse_error_expected("while parsing struct type specifier",
2711                                              T_IDENTIFIER, '{', NULL);
2712                 } else {
2713                         parse_error_expected("while parsing union type specifier",
2714                                              T_IDENTIFIER, '{', NULL);
2715                 }
2716
2717                 return NULL;
2718         }
2719
2720         if (declaration == NULL) {
2721                 declaration = allocate_declaration_zero();
2722                 declaration->namespc         =
2723                         (is_struct ? NAMESPACE_STRUCT : NAMESPACE_UNION);
2724                 declaration->source_position = token.source_position;
2725                 declaration->symbol          = symbol;
2726                 declaration->parent_scope    = scope;
2727                 if (symbol != NULL) {
2728                         environment_push(declaration);
2729                 }
2730                 append_declaration(declaration);
2731         }
2732
2733         if (token.type == '{') {
2734                 declaration->init.complete = true;
2735
2736                 parse_compound_type_entries(declaration);
2737                 modifiers |= parse_attributes(&attributes);
2738         }
2739
2740         declaration->modifiers |= modifiers;
2741         return declaration;
2742 }
2743
2744 static void parse_enum_entries(type_t *const enum_type)
2745 {
2746         eat('{');
2747
2748         if (token.type == '}') {
2749                 next_token();
2750                 errorf(HERE, "empty enum not allowed");
2751                 return;
2752         }
2753
2754         add_anchor_token('}');
2755         do {
2756                 if (token.type != T_IDENTIFIER) {
2757                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
2758                         eat_block();
2759                         rem_anchor_token('}');
2760                         return;
2761                 }
2762
2763                 declaration_t *const entry = allocate_declaration_zero();
2764                 entry->storage_class   = STORAGE_CLASS_ENUM_ENTRY;
2765                 entry->type            = enum_type;
2766                 entry->symbol          = token.v.symbol;
2767                 entry->source_position = token.source_position;
2768                 next_token();
2769
2770                 if (token.type == '=') {
2771                         next_token();
2772                         expression_t *value = parse_constant_expression();
2773
2774                         value = create_implicit_cast(value, enum_type);
2775                         entry->init.enum_value = value;
2776
2777                         /* TODO semantic */
2778                 }
2779
2780                 record_declaration(entry, false);
2781
2782                 if (token.type != ',')
2783                         break;
2784                 next_token();
2785         } while (token.type != '}');
2786         rem_anchor_token('}');
2787
2788         expect('}');
2789
2790 end_error:
2791         ;
2792 }
2793
2794 static type_t *parse_enum_specifier(void)
2795 {
2796         gnu_attribute_t *attributes = NULL;
2797         declaration_t   *declaration;
2798         symbol_t        *symbol;
2799
2800         eat(T_enum);
2801         if (token.type == T_IDENTIFIER) {
2802                 symbol = token.v.symbol;
2803                 next_token();
2804
2805                 declaration = get_declaration(symbol, NAMESPACE_ENUM);
2806         } else if (token.type != '{') {
2807                 parse_error_expected("while parsing enum type specifier",
2808                                      T_IDENTIFIER, '{', NULL);
2809                 return NULL;
2810         } else {
2811                 declaration = NULL;
2812                 symbol      = NULL;
2813         }
2814
2815         if (declaration == NULL) {
2816                 declaration = allocate_declaration_zero();
2817                 declaration->namespc         = NAMESPACE_ENUM;
2818                 declaration->source_position = token.source_position;
2819                 declaration->symbol          = symbol;
2820                 declaration->parent_scope  = scope;
2821         }
2822
2823         type_t *const type      = allocate_type_zero(TYPE_ENUM, &declaration->source_position);
2824         type->enumt.declaration = declaration;
2825
2826         if (token.type == '{') {
2827                 if (declaration->init.complete) {
2828                         errorf(HERE, "multiple definitions of enum %Y", symbol);
2829                 }
2830                 if (symbol != NULL) {
2831                         environment_push(declaration);
2832                 }
2833                 append_declaration(declaration);
2834                 declaration->init.complete = true;
2835
2836                 parse_enum_entries(type);
2837                 parse_attributes(&attributes);
2838         }
2839
2840         return type;
2841 }
2842
2843 /**
2844  * if a symbol is a typedef to another type, return true
2845  */
2846 static bool is_typedef_symbol(symbol_t *symbol)
2847 {
2848         const declaration_t *const declaration =
2849                 get_declaration(symbol, NAMESPACE_NORMAL);
2850         return
2851                 declaration != NULL &&
2852                 declaration->storage_class == STORAGE_CLASS_TYPEDEF;
2853 }
2854
2855 static type_t *parse_typeof(void)
2856 {
2857         eat(T___typeof__);
2858
2859         type_t *type;
2860
2861         expect('(');
2862         add_anchor_token(')');
2863
2864         expression_t *expression  = NULL;
2865
2866 restart:
2867         switch(token.type) {
2868         case T___extension__:
2869                 /* This can be a prefix to a typename or an expression.  We simply eat
2870                  * it now. */
2871                 do {
2872                         next_token();
2873                 } while (token.type == T___extension__);
2874                 goto restart;
2875
2876         case T_IDENTIFIER:
2877                 if (is_typedef_symbol(token.v.symbol)) {
2878                         type = parse_typename();
2879                 } else {
2880                         expression = parse_expression();
2881                         type       = expression->base.type;
2882                 }
2883                 break;
2884
2885         TYPENAME_START
2886                 type = parse_typename();
2887                 break;
2888
2889         default:
2890                 expression = parse_expression();
2891                 type       = expression->base.type;
2892                 break;
2893         }
2894
2895         rem_anchor_token(')');
2896         expect(')');
2897
2898         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF, &expression->base.source_position);
2899         typeof_type->typeoft.expression  = expression;
2900         typeof_type->typeoft.typeof_type = type;
2901
2902         return typeof_type;
2903 end_error:
2904         return NULL;
2905 }
2906
2907 typedef enum specifiers_t {
2908         SPECIFIER_SIGNED    = 1 << 0,
2909         SPECIFIER_UNSIGNED  = 1 << 1,
2910         SPECIFIER_LONG      = 1 << 2,
2911         SPECIFIER_INT       = 1 << 3,
2912         SPECIFIER_DOUBLE    = 1 << 4,
2913         SPECIFIER_CHAR      = 1 << 5,
2914         SPECIFIER_SHORT     = 1 << 6,
2915         SPECIFIER_LONG_LONG = 1 << 7,
2916         SPECIFIER_FLOAT     = 1 << 8,
2917         SPECIFIER_BOOL      = 1 << 9,
2918         SPECIFIER_VOID      = 1 << 10,
2919         SPECIFIER_INT8      = 1 << 11,
2920         SPECIFIER_INT16     = 1 << 12,
2921         SPECIFIER_INT32     = 1 << 13,
2922         SPECIFIER_INT64     = 1 << 14,
2923         SPECIFIER_INT128    = 1 << 15,
2924         SPECIFIER_COMPLEX   = 1 << 16,
2925         SPECIFIER_IMAGINARY = 1 << 17,
2926 } specifiers_t;
2927
2928 static type_t *create_builtin_type(symbol_t *const symbol,
2929                                    type_t *const real_type)
2930 {
2931         type_t *type            = allocate_type_zero(TYPE_BUILTIN, &builtin_source_position);
2932         type->builtin.symbol    = symbol;
2933         type->builtin.real_type = real_type;
2934
2935         type_t *result = typehash_insert(type);
2936         if (type != result) {
2937                 free_type(type);
2938         }
2939
2940         return result;
2941 }
2942
2943 static type_t *get_typedef_type(symbol_t *symbol)
2944 {
2945         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
2946         if (declaration == NULL ||
2947            declaration->storage_class != STORAGE_CLASS_TYPEDEF)
2948                 return NULL;
2949
2950         type_t *type               = allocate_type_zero(TYPE_TYPEDEF, &declaration->source_position);
2951         type->typedeft.declaration = declaration;
2952
2953         return type;
2954 }
2955
2956 /**
2957  * check for the allowed MS alignment values.
2958  */
2959 static bool check_alignment_value(long long intvalue)
2960 {
2961         if (intvalue < 1 || intvalue > 8192) {
2962                 errorf(HERE, "illegal alignment value");
2963                 return false;
2964         }
2965         unsigned v = (unsigned)intvalue;
2966         for(unsigned i = 1; i <= 8192; i += i) {
2967                 if (i == v)
2968                         return true;
2969         }
2970         errorf(HERE, "alignment must be power of two");
2971         return false;
2972 }
2973
2974 #define DET_MOD(name, tag) do { \
2975         if (*modifiers & tag) warningf(HERE, #name " used more than once"); \
2976         *modifiers |= tag; \
2977 } while (0)
2978
2979 static void parse_microsoft_extended_decl_modifier(declaration_specifiers_t *specifiers)
2980 {
2981         decl_modifiers_t *modifiers = &specifiers->modifiers;
2982
2983         while (true) {
2984                 if (token.type == T_restrict) {
2985                         next_token();
2986                         DET_MOD(restrict, DM_RESTRICT);
2987                         goto end_loop;
2988                 } else if (token.type != T_IDENTIFIER)
2989                         break;
2990                 symbol_t *symbol = token.v.symbol;
2991                 if (symbol == sym_align) {
2992                         next_token();
2993                         expect('(');
2994                         if (token.type != T_INTEGER)
2995                                 goto end_error;
2996                         if (check_alignment_value(token.v.intvalue)) {
2997                                 if (specifiers->alignment != 0)
2998                                         warningf(HERE, "align used more than once");
2999                                 specifiers->alignment = (unsigned char)token.v.intvalue;
3000                         }
3001                         next_token();
3002                         expect(')');
3003                 } else if (symbol == sym_allocate) {
3004                         next_token();
3005                         expect('(');
3006                         if (token.type != T_IDENTIFIER)
3007                                 goto end_error;
3008                         (void)token.v.symbol;
3009                         expect(')');
3010                 } else if (symbol == sym_dllimport) {
3011                         next_token();
3012                         DET_MOD(dllimport, DM_DLLIMPORT);
3013                 } else if (symbol == sym_dllexport) {
3014                         next_token();
3015                         DET_MOD(dllexport, DM_DLLEXPORT);
3016                 } else if (symbol == sym_thread) {
3017                         next_token();
3018                         DET_MOD(thread, DM_THREAD);
3019                 } else if (symbol == sym_naked) {
3020                         next_token();
3021                         DET_MOD(naked, DM_NAKED);
3022                 } else if (symbol == sym_noinline) {
3023                         next_token();
3024                         DET_MOD(noinline, DM_NOINLINE);
3025                 } else if (symbol == sym_noreturn) {
3026                         next_token();
3027                         DET_MOD(noreturn, DM_NORETURN);
3028                 } else if (symbol == sym_nothrow) {
3029                         next_token();
3030                         DET_MOD(nothrow, DM_NOTHROW);
3031                 } else if (symbol == sym_novtable) {
3032                         next_token();
3033                         DET_MOD(novtable, DM_NOVTABLE);
3034                 } else if (symbol == sym_property) {
3035                         next_token();
3036                         expect('(');
3037                         for(;;) {
3038                                 bool is_get = false;
3039                                 if (token.type != T_IDENTIFIER)
3040                                         goto end_error;
3041                                 if (token.v.symbol == sym_get) {
3042                                         is_get = true;
3043                                 } else if (token.v.symbol == sym_put) {
3044                                 } else {
3045                                         errorf(HERE, "Bad property name '%Y'", token.v.symbol);
3046                                         goto end_error;
3047                                 }
3048                                 next_token();
3049                                 expect('=');
3050                                 if (token.type != T_IDENTIFIER)
3051                                         goto end_error;
3052                                 if (is_get) {
3053                                         if (specifiers->get_property_sym != NULL) {
3054                                                 errorf(HERE, "get property name already specified");
3055                                         } else {
3056                                                 specifiers->get_property_sym = token.v.symbol;
3057                                         }
3058                                 } else {
3059                                         if (specifiers->put_property_sym != NULL) {
3060                                                 errorf(HERE, "put property name already specified");
3061                                         } else {
3062                                                 specifiers->put_property_sym = token.v.symbol;
3063                                         }
3064                                 }
3065                                 next_token();
3066                                 if (token.type == ',') {
3067                                         next_token();
3068                                         continue;
3069                                 }
3070                                 break;
3071                         }
3072                         expect(')');
3073                 } else if (symbol == sym_selectany) {
3074                         next_token();
3075                         DET_MOD(selectany, DM_SELECTANY);
3076                 } else if (symbol == sym_uuid) {
3077                         next_token();
3078                         expect('(');
3079                         if (token.type != T_STRING_LITERAL)
3080                                 goto end_error;
3081                         next_token();
3082                         expect(')');
3083                 } else if (symbol == sym_deprecated) {
3084                         next_token();
3085                         if (specifiers->deprecated != 0)
3086                                 warningf(HERE, "deprecated used more than once");
3087                         specifiers->deprecated = 1;
3088                         if (token.type == '(') {
3089                                 next_token();
3090                                 if (token.type == T_STRING_LITERAL) {
3091                                         specifiers->deprecated_string = token.v.string.begin;
3092                                         next_token();
3093                                 } else {
3094                                         errorf(HERE, "string literal expected");
3095                                 }
3096                                 expect(')');
3097                         }
3098                 } else if (symbol == sym_noalias) {
3099                         next_token();
3100                         DET_MOD(noalias, DM_NOALIAS);
3101                 } else {
3102                         warningf(HERE, "Unknown modifier %Y ignored", token.v.symbol);
3103                         next_token();
3104                         if (token.type == '(')
3105                                 skip_until(')');
3106                 }
3107 end_loop:
3108                 if (token.type == ',')
3109                         next_token();
3110         }
3111 end_error:
3112         return;
3113 }
3114
3115 static declaration_t *create_error_declaration(symbol_t *symbol, storage_class_tag_t storage_class)
3116 {
3117         declaration_t *const decl    = allocate_declaration_zero();
3118         decl->source_position        = *HERE;
3119         decl->declared_storage_class = storage_class;
3120         decl->storage_class          =
3121                 storage_class != STORAGE_CLASS_NONE || scope == global_scope ?
3122                         storage_class : STORAGE_CLASS_AUTO;
3123         decl->symbol                 = symbol;
3124         decl->implicit               = true;
3125         record_declaration(decl, false);
3126         return decl;
3127 }
3128
3129 /**
3130  * Finish the construction of a struct type by calculating
3131  * its size, offsets, alignment.
3132  */
3133 static void finish_struct_type(compound_type_t *type) {
3134         if (type->declaration == NULL)
3135                 return;
3136         declaration_t *struct_decl = type->declaration;
3137         if (! struct_decl->init.complete)
3138                 return;
3139
3140         il_size_t      size           = 0;
3141         il_size_t      offset;
3142         il_alignment_t alignment      = 1;
3143         bool           need_pad       = false;
3144
3145         declaration_t *entry = struct_decl->scope.declarations;
3146         for (; entry != NULL; entry = entry->next) {
3147                 if (entry->namespc != NAMESPACE_NORMAL)
3148                         continue;
3149
3150                 type_t *m_type = skip_typeref(entry->type);
3151                 if (! is_type_valid(m_type)) {
3152                         /* simply ignore errors here */
3153                         continue;
3154                 }
3155                 il_alignment_t m_alignment = m_type->base.alignment;
3156                 if (m_alignment > alignment)
3157                         alignment = m_alignment;
3158
3159                 offset = (size + m_alignment - 1) & -m_alignment;
3160
3161                 if (offset > size)
3162                         need_pad = true;
3163                 entry->offset = offset;
3164                 size = offset + m_type->base.size;
3165         }
3166         if (type->base.alignment != 0) {
3167                 alignment = type->base.alignment;
3168         }
3169
3170         offset = (size + alignment - 1) & -alignment;
3171         if (offset > size)
3172                 need_pad = true;
3173
3174         if (warning.padded && need_pad) {
3175                 warningf(&struct_decl->source_position,
3176                         "'%#T' needs padding", type, struct_decl->symbol);
3177         }
3178         if (warning.packed && !need_pad) {
3179                 warningf(&struct_decl->source_position,
3180                         "superfluous packed attribute on '%#T'",
3181                         type, struct_decl->symbol);
3182         }
3183
3184         type->base.size      = offset;
3185         type->base.alignment = alignment;
3186 }
3187
3188 /**
3189  * Finish the construction of an union type by calculating
3190  * its size and alignment.
3191  */
3192 static void finish_union_type(compound_type_t *type) {
3193         if (type->declaration == NULL)
3194                 return;
3195         declaration_t *union_decl = type->declaration;
3196         if (! union_decl->init.complete)
3197                 return;
3198
3199         il_size_t      size      = 0;
3200         il_alignment_t alignment = 1;
3201
3202         declaration_t *entry = union_decl->scope.declarations;
3203         for (; entry != NULL; entry = entry->next) {
3204                 if (entry->namespc != NAMESPACE_NORMAL)
3205                         continue;
3206
3207                 type_t *m_type = skip_typeref(entry->type);
3208                 if (! is_type_valid(m_type))
3209                         continue;
3210
3211                 entry->offset = 0;
3212                 if (m_type->base.size > size)
3213                         size = m_type->base.size;
3214                 if (m_type->base.alignment > alignment)
3215                         alignment = m_type->base.alignment;
3216         }
3217         if (type->base.alignment != 0) {
3218                 alignment = type->base.alignment;
3219         }
3220         size = (size + alignment - 1) & -alignment;
3221         type->base.size      = size;
3222         type->base.alignment = alignment;
3223 }
3224
3225 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
3226 {
3227         type_t            *type            = NULL;
3228         type_qualifiers_t  qualifiers      = TYPE_QUALIFIER_NONE;
3229         type_modifiers_t   modifiers       = TYPE_MODIFIER_NONE;
3230         unsigned           type_specifiers = 0;
3231         bool               newtype         = false;
3232         bool               saw_error       = false;
3233
3234         specifiers->source_position = token.source_position;
3235
3236         while (true) {
3237                 specifiers->modifiers
3238                         |= parse_attributes(&specifiers->gnu_attributes);
3239                 if (specifiers->modifiers & DM_TRANSPARENT_UNION)
3240                         modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3241
3242                 switch(token.type) {
3243
3244                 /* storage class */
3245 #define MATCH_STORAGE_CLASS(token, class)                                  \
3246                 case token:                                                        \
3247                         if (specifiers->declared_storage_class != STORAGE_CLASS_NONE) { \
3248                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
3249                         }                                                              \
3250                         specifiers->declared_storage_class = class;                    \
3251                         next_token();                                                  \
3252                         break;
3253
3254                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
3255                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
3256                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
3257                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
3258                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
3259
3260                 case T__declspec:
3261                         next_token();
3262                         expect('(');
3263                         add_anchor_token(')');
3264                         parse_microsoft_extended_decl_modifier(specifiers);
3265                         rem_anchor_token(')');
3266                         expect(')');
3267                         break;
3268
3269                 case T___thread:
3270                         switch (specifiers->declared_storage_class) {
3271                         case STORAGE_CLASS_NONE:
3272                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD;
3273                                 break;
3274
3275                         case STORAGE_CLASS_EXTERN:
3276                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_EXTERN;
3277                                 break;
3278
3279                         case STORAGE_CLASS_STATIC:
3280                                 specifiers->declared_storage_class = STORAGE_CLASS_THREAD_STATIC;
3281                                 break;
3282
3283                         default:
3284                                 errorf(HERE, "multiple storage classes in declaration specifiers");
3285                                 break;
3286                         }
3287                         next_token();
3288                         break;
3289
3290                 /* type qualifiers */
3291 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
3292                 case token:                                                     \
3293                         qualifiers |= qualifier;                                    \
3294                         next_token();                                               \
3295                         break
3296
3297                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3298                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3299                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3300                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3301                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3302                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3303                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3304                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3305
3306                 case T___extension__:
3307                         /* TODO */
3308                         next_token();
3309                         break;
3310
3311                 /* type specifiers */
3312 #define MATCH_SPECIFIER(token, specifier, name)                         \
3313                 case token:                                                     \
3314                         next_token();                                               \
3315                         if (type_specifiers & specifier) {                           \
3316                                 errorf(HERE, "multiple " name " type specifiers given"); \
3317                         } else {                                                    \
3318                                 type_specifiers |= specifier;                           \
3319                         }                                                           \
3320                         break
3321
3322                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
3323                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
3324                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
3325                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
3326                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
3327                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
3328                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
3329                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
3330                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
3331                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
3332                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
3333                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
3334                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
3335                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
3336                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
3337                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
3338
3339                 case T__forceinline:
3340                         /* only in microsoft mode */
3341                         specifiers->modifiers |= DM_FORCEINLINE;
3342                         /* FALLTHROUGH */
3343
3344                 case T_inline:
3345                         next_token();
3346                         specifiers->is_inline = true;
3347                         break;
3348
3349                 case T_long:
3350                         next_token();
3351                         if (type_specifiers & SPECIFIER_LONG_LONG) {
3352                                 errorf(HERE, "multiple type specifiers given");
3353                         } else if (type_specifiers & SPECIFIER_LONG) {
3354                                 type_specifiers |= SPECIFIER_LONG_LONG;
3355                         } else {
3356                                 type_specifiers |= SPECIFIER_LONG;
3357                         }
3358                         break;
3359
3360                 case T_struct: {
3361                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT, HERE);
3362
3363                         type->compound.declaration = parse_compound_type_specifier(true);
3364                         finish_struct_type(&type->compound);
3365                         break;
3366                 }
3367                 case T_union: {
3368                         type = allocate_type_zero(TYPE_COMPOUND_UNION, HERE);
3369                         type->compound.declaration = parse_compound_type_specifier(false);
3370                         if (type->compound.declaration->modifiers & DM_TRANSPARENT_UNION)
3371                                 modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3372                         break;
3373                         finish_union_type(&type->compound);
3374                 }
3375                 case T_enum:
3376                         type = parse_enum_specifier();
3377                         break;
3378                 case T___typeof__:
3379                         type = parse_typeof();
3380                         break;
3381                 case T___builtin_va_list:
3382                         type = duplicate_type(type_valist);
3383                         next_token();
3384                         break;
3385
3386                 case T_IDENTIFIER: {
3387                         /* only parse identifier if we haven't found a type yet */
3388                         if (type != NULL || type_specifiers != 0) {
3389                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3390                                  * declaration, so it doesn't generate errors about expecting '(' or
3391                                  * '{' later on. */
3392                                 switch (look_ahead(1)->type) {
3393                                         STORAGE_CLASSES
3394                                         TYPE_SPECIFIERS
3395                                         case T_const:
3396                                         case T_restrict:
3397                                         case T_volatile:
3398                                         case T_inline:
3399                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3400                                         case T_IDENTIFIER:
3401                                         case '*':
3402                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3403                                                 next_token();
3404                                                 continue;
3405
3406                                         default:
3407                                                 goto finish_specifiers;
3408                                 }
3409                         }
3410
3411                         type_t *const typedef_type = get_typedef_type(token.v.symbol);
3412                         if (typedef_type == NULL) {
3413                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3414                                  * declaration, so it doesn't generate 'implicit int' followed by more
3415                                  * errors later on. */
3416                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3417                                 switch (la1_type) {
3418                                         DECLARATION_START
3419                                         case T_IDENTIFIER:
3420                                         case '*': {
3421                                                 errorf(HERE, "%K does not name a type", &token);
3422
3423                                                 declaration_t *const decl =
3424                                                         create_error_declaration(token.v.symbol, STORAGE_CLASS_TYPEDEF);
3425
3426                                                 type = allocate_type_zero(TYPE_TYPEDEF, HERE);
3427                                                 type->typedeft.declaration = decl;
3428
3429                                                 next_token();
3430                                                 saw_error = true;
3431                                                 if (la1_type == '*')
3432                                                         goto finish_specifiers;
3433                                                 continue;
3434                                         }
3435
3436                                         default:
3437                                                 goto finish_specifiers;
3438                                 }
3439                         }
3440
3441                         next_token();
3442                         type = typedef_type;
3443                         break;
3444                 }
3445
3446                 /* function specifier */
3447                 default:
3448                         goto finish_specifiers;
3449                 }
3450         }
3451
3452 finish_specifiers:
3453         if (type == NULL || (saw_error && type_specifiers != 0)) {
3454                 atomic_type_kind_t atomic_type;
3455
3456                 /* match valid basic types */
3457                 switch(type_specifiers) {
3458                 case SPECIFIER_VOID:
3459                         atomic_type = ATOMIC_TYPE_VOID;
3460                         break;
3461                 case SPECIFIER_CHAR:
3462                         atomic_type = ATOMIC_TYPE_CHAR;
3463                         break;
3464                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3465                         atomic_type = ATOMIC_TYPE_SCHAR;
3466                         break;
3467                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3468                         atomic_type = ATOMIC_TYPE_UCHAR;
3469                         break;
3470                 case SPECIFIER_SHORT:
3471                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3472                 case SPECIFIER_SHORT | SPECIFIER_INT:
3473                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3474                         atomic_type = ATOMIC_TYPE_SHORT;
3475                         break;
3476                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3477                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3478                         atomic_type = ATOMIC_TYPE_USHORT;
3479                         break;
3480                 case SPECIFIER_INT:
3481                 case SPECIFIER_SIGNED:
3482                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3483                         atomic_type = ATOMIC_TYPE_INT;
3484                         break;
3485                 case SPECIFIER_UNSIGNED:
3486                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3487                         atomic_type = ATOMIC_TYPE_UINT;
3488                         break;
3489                 case SPECIFIER_LONG:
3490                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3491                 case SPECIFIER_LONG | SPECIFIER_INT:
3492                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3493                         atomic_type = ATOMIC_TYPE_LONG;
3494                         break;
3495                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3496                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3497                         atomic_type = ATOMIC_TYPE_ULONG;
3498                         break;
3499
3500                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3501                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3502                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3503                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3504                         | SPECIFIER_INT:
3505                         atomic_type = ATOMIC_TYPE_LONGLONG;
3506                         goto warn_about_long_long;
3507
3508                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3509                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3510                         | SPECIFIER_INT:
3511                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3512 warn_about_long_long:
3513                         if (warning.long_long) {
3514                                 warningf(&specifiers->source_position,
3515                                          "ISO C90 does not support 'long long'");
3516                         }
3517                         break;
3518
3519                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3520                         atomic_type = unsigned_int8_type_kind;
3521                         break;
3522
3523                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3524                         atomic_type = unsigned_int16_type_kind;
3525                         break;
3526
3527                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3528                         atomic_type = unsigned_int32_type_kind;
3529                         break;
3530
3531                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3532                         atomic_type = unsigned_int64_type_kind;
3533                         break;
3534
3535                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3536                         atomic_type = unsigned_int128_type_kind;
3537                         break;
3538
3539                 case SPECIFIER_INT8:
3540                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3541                         atomic_type = int8_type_kind;
3542                         break;
3543
3544                 case SPECIFIER_INT16:
3545                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3546                         atomic_type = int16_type_kind;
3547                         break;
3548
3549                 case SPECIFIER_INT32:
3550                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3551                         atomic_type = int32_type_kind;
3552                         break;
3553
3554                 case SPECIFIER_INT64:
3555                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3556                         atomic_type = int64_type_kind;
3557                         break;
3558
3559                 case SPECIFIER_INT128:
3560                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3561                         atomic_type = int128_type_kind;
3562                         break;
3563
3564                 case SPECIFIER_FLOAT:
3565                         atomic_type = ATOMIC_TYPE_FLOAT;
3566                         break;
3567                 case SPECIFIER_DOUBLE:
3568                         atomic_type = ATOMIC_TYPE_DOUBLE;
3569                         break;
3570                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3571                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3572                         break;
3573                 case SPECIFIER_BOOL:
3574                         atomic_type = ATOMIC_TYPE_BOOL;
3575                         break;
3576                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3577                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3578                         atomic_type = ATOMIC_TYPE_FLOAT;
3579                         break;
3580                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3581                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3582                         atomic_type = ATOMIC_TYPE_DOUBLE;
3583                         break;
3584                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3585                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3586                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3587                         break;
3588                 default:
3589                         /* invalid specifier combination, give an error message */
3590                         if (type_specifiers == 0) {
3591                                 if (saw_error)
3592                                         goto end_error;
3593
3594                                 if (!strict_mode) {
3595                                         if (warning.implicit_int) {
3596                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3597                                         }
3598                                         atomic_type = ATOMIC_TYPE_INT;
3599                                         break;
3600                                 } else {
3601                                         errorf(HERE, "no type specifiers given in declaration");
3602                                 }
3603                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3604                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3605                                 errorf(HERE, "signed and unsigned specifiers given");
3606                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3607                                 errorf(HERE, "only integer types can be signed or unsigned");
3608                         } else {
3609                                 errorf(HERE, "multiple datatypes in declaration");
3610                         }
3611                         goto end_error;
3612                 }
3613
3614                 if (type_specifiers & SPECIFIER_COMPLEX) {
3615                         type                = allocate_type_zero(TYPE_COMPLEX, &builtin_source_position);
3616                         type->complex.akind = atomic_type;
3617                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
3618                         type                  = allocate_type_zero(TYPE_IMAGINARY, &builtin_source_position);
3619                         type->imaginary.akind = atomic_type;
3620                 } else {
3621                         type               = allocate_type_zero(TYPE_ATOMIC, &builtin_source_position);
3622                         type->atomic.akind = atomic_type;
3623                 }
3624                 newtype = true;
3625         } else if (type_specifiers != 0) {
3626                 errorf(HERE, "multiple datatypes in declaration");
3627         }
3628
3629         /* FIXME: check type qualifiers here */
3630
3631         type->base.qualifiers = qualifiers;
3632         type->base.modifiers  = modifiers;
3633
3634         type_t *result = typehash_insert(type);
3635         if (newtype && result != type) {
3636                 free_type(type);
3637         }
3638
3639         specifiers->type = result;
3640         return;
3641
3642 end_error:
3643         specifiers->type = type_error_type;
3644         return;
3645 }
3646
3647 static type_qualifiers_t parse_type_qualifiers(void)
3648 {
3649         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3650
3651         while (true) {
3652                 switch(token.type) {
3653                 /* type qualifiers */
3654                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3655                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3656                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3657                 /* microsoft extended type modifiers */
3658                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3659                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3660                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3661                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3662                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3663
3664                 default:
3665                         return qualifiers;
3666                 }
3667         }
3668 }
3669
3670 static declaration_t *parse_identifier_list(void)
3671 {
3672         declaration_t *declarations     = NULL;
3673         declaration_t *last_declaration = NULL;
3674         do {
3675                 declaration_t *const declaration = allocate_declaration_zero();
3676                 declaration->type            = NULL; /* a K&R parameter list has no types, yet */
3677                 declaration->source_position = token.source_position;
3678                 declaration->symbol          = token.v.symbol;
3679                 next_token();
3680
3681                 if (last_declaration != NULL) {
3682                         last_declaration->next = declaration;
3683                 } else {
3684                         declarations = declaration;
3685                 }
3686                 last_declaration = declaration;
3687
3688                 if (token.type != ',') {
3689                         break;
3690                 }
3691                 next_token();
3692         } while (token.type == T_IDENTIFIER);
3693
3694         return declarations;
3695 }
3696
3697 static type_t *automatic_type_conversion(type_t *orig_type);
3698
3699 static void semantic_parameter(declaration_t *declaration)
3700 {
3701         /* TODO: improve error messages */
3702         source_position_t const* const pos = &declaration->source_position;
3703
3704         switch (declaration->declared_storage_class) {
3705                 case STORAGE_CLASS_TYPEDEF:
3706                         errorf(pos, "typedef not allowed in parameter list");
3707                         break;
3708
3709                 /* Allowed storage classes */
3710                 case STORAGE_CLASS_NONE:
3711                 case STORAGE_CLASS_REGISTER:
3712                         break;
3713
3714                 default:
3715                         errorf(pos, "parameter may only have none or register storage class");
3716                         break;
3717         }
3718
3719         type_t *const orig_type = declaration->type;
3720         /* §6.7.5.3(7): Array as last part of a parameter type is just syntactic
3721          * sugar.  Turn it into a pointer.
3722          * §6.7.5.3(8): A declaration of a parameter as ``function returning type''
3723          * shall be adjusted to ``pointer to function returning type'', as in 6.3.2.1.
3724          */
3725         type_t *const type = automatic_type_conversion(orig_type);
3726         declaration->type = type;
3727
3728         if (is_type_incomplete(skip_typeref(type))) {
3729                 errorf(pos, "parameter '%#T' is of incomplete type",
3730                        orig_type, declaration->symbol);
3731         }
3732 }
3733
3734 static declaration_t *parse_parameter(void)
3735 {
3736         declaration_specifiers_t specifiers;
3737         memset(&specifiers, 0, sizeof(specifiers));
3738
3739         parse_declaration_specifiers(&specifiers);
3740
3741         declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/true);
3742
3743         return declaration;
3744 }
3745
3746 static declaration_t *parse_parameters(function_type_t *type)
3747 {
3748         declaration_t *declarations = NULL;
3749
3750         eat('(');
3751         add_anchor_token(')');
3752         int saved_comma_state = save_and_reset_anchor_state(',');
3753
3754         if (token.type == T_IDENTIFIER &&
3755             !is_typedef_symbol(token.v.symbol)) {
3756                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
3757                 if (la1_type == ',' || la1_type == ')') {
3758                         type->kr_style_parameters = true;
3759                         declarations = parse_identifier_list();
3760                         goto parameters_finished;
3761                 }
3762         }
3763
3764         if (token.type == ')') {
3765                 type->unspecified_parameters = 1;
3766                 goto parameters_finished;
3767         }
3768
3769         declaration_t        *declaration;
3770         declaration_t        *last_declaration = NULL;
3771         function_parameter_t *parameter;
3772         function_parameter_t *last_parameter = NULL;
3773
3774         while (true) {
3775                 switch(token.type) {
3776                 case T_DOTDOTDOT:
3777                         next_token();
3778                         type->variadic = 1;
3779                         goto parameters_finished;
3780
3781                 case T_IDENTIFIER:
3782                 case T___extension__:
3783                 DECLARATION_START
3784                         declaration = parse_parameter();
3785
3786                         /* func(void) is not a parameter */
3787                         if (last_parameter == NULL
3788                                         && token.type == ')'
3789                                         && declaration->symbol == NULL
3790                                         && skip_typeref(declaration->type) == type_void) {
3791                                 goto parameters_finished;
3792                         }
3793                         semantic_parameter(declaration);
3794
3795                         parameter       = obstack_alloc(type_obst, sizeof(parameter[0]));
3796                         memset(parameter, 0, sizeof(parameter[0]));
3797                         parameter->type = declaration->type;
3798
3799                         if (last_parameter != NULL) {
3800                                 last_declaration->next = declaration;
3801                                 last_parameter->next   = parameter;
3802                         } else {
3803                                 type->parameters = parameter;
3804                                 declarations     = declaration;
3805                         }
3806                         last_parameter   = parameter;
3807                         last_declaration = declaration;
3808                         break;
3809
3810                 default:
3811                         goto parameters_finished;
3812                 }
3813                 if (token.type != ',') {
3814                         goto parameters_finished;
3815                 }
3816                 next_token();
3817         }
3818
3819
3820 parameters_finished:
3821         rem_anchor_token(')');
3822         expect(')');
3823
3824         restore_anchor_state(',', saved_comma_state);
3825         return declarations;
3826
3827 end_error:
3828         restore_anchor_state(',', saved_comma_state);
3829         return NULL;
3830 }
3831
3832 typedef enum construct_type_kind_t {
3833         CONSTRUCT_INVALID,
3834         CONSTRUCT_POINTER,
3835         CONSTRUCT_FUNCTION,
3836         CONSTRUCT_ARRAY
3837 } construct_type_kind_t;
3838
3839 typedef struct construct_type_t construct_type_t;
3840 struct construct_type_t {
3841         construct_type_kind_t  kind;
3842         construct_type_t      *next;
3843 };
3844
3845 typedef struct parsed_pointer_t parsed_pointer_t;
3846 struct parsed_pointer_t {
3847         construct_type_t  construct_type;
3848         type_qualifiers_t type_qualifiers;
3849 };
3850
3851 typedef struct construct_function_type_t construct_function_type_t;
3852 struct construct_function_type_t {
3853         construct_type_t  construct_type;
3854         type_t           *function_type;
3855 };
3856
3857 typedef struct parsed_array_t parsed_array_t;
3858 struct parsed_array_t {
3859         construct_type_t  construct_type;
3860         type_qualifiers_t type_qualifiers;
3861         bool              is_static;
3862         bool              is_variable;
3863         expression_t     *size;
3864 };
3865
3866 typedef struct construct_base_type_t construct_base_type_t;
3867 struct construct_base_type_t {
3868         construct_type_t  construct_type;
3869         type_t           *type;
3870 };
3871
3872 static construct_type_t *parse_pointer_declarator(void)
3873 {
3874         eat('*');
3875
3876         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
3877         memset(pointer, 0, sizeof(pointer[0]));
3878         pointer->construct_type.kind = CONSTRUCT_POINTER;
3879         pointer->type_qualifiers     = parse_type_qualifiers();
3880
3881         return (construct_type_t*) pointer;
3882 }
3883
3884 static construct_type_t *parse_array_declarator(void)
3885 {
3886         eat('[');
3887         add_anchor_token(']');
3888
3889         parsed_array_t *array = obstack_alloc(&temp_obst, sizeof(array[0]));
3890         memset(array, 0, sizeof(array[0]));
3891         array->construct_type.kind = CONSTRUCT_ARRAY;
3892
3893         if (token.type == T_static) {
3894                 array->is_static = true;
3895                 next_token();
3896         }
3897
3898         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
3899         if (type_qualifiers != 0) {
3900                 if (token.type == T_static) {
3901                         array->is_static = true;
3902                         next_token();
3903                 }
3904         }
3905         array->type_qualifiers = type_qualifiers;
3906
3907         if (token.type == '*' && look_ahead(1)->type == ']') {
3908                 array->is_variable = true;
3909                 next_token();
3910         } else if (token.type != ']') {
3911                 array->size = parse_assignment_expression();
3912         }
3913
3914         rem_anchor_token(']');
3915         expect(']');
3916
3917         return (construct_type_t*) array;
3918 end_error:
3919         return NULL;
3920 }
3921
3922 static construct_type_t *parse_function_declarator(declaration_t *declaration)
3923 {
3924         type_t *type;
3925         if (declaration != NULL) {
3926                 type = allocate_type_zero(TYPE_FUNCTION, &declaration->source_position);
3927
3928                 unsigned mask = declaration->modifiers & (DM_CDECL|DM_STDCALL|DM_FASTCALL|DM_THISCALL);
3929
3930                 if (mask & (mask-1)) {
3931                         const char *first = NULL, *second = NULL;
3932
3933                         /* more than one calling convention set */
3934                         if (declaration->modifiers & DM_CDECL) {
3935                                 if (first == NULL)       first = "cdecl";
3936                                 else if (second == NULL) second = "cdecl";
3937                         }
3938                         if (declaration->modifiers & DM_STDCALL) {
3939                                 if (first == NULL)       first = "stdcall";
3940                                 else if (second == NULL) second = "stdcall";
3941                         }
3942                         if (declaration->modifiers & DM_FASTCALL) {
3943                                 if (first == NULL)       first = "fastcall";
3944                                 else if (second == NULL) second = "fastcall";
3945                         }
3946                         if (declaration->modifiers & DM_THISCALL) {
3947                                 if (first == NULL)       first = "thiscall";
3948                                 else if (second == NULL) second = "thiscall";
3949                         }
3950                         errorf(&declaration->source_position, "%s and %s attributes are not compatible", first, second);
3951                 }
3952
3953                 if (declaration->modifiers & DM_CDECL)
3954                         type->function.calling_convention = CC_CDECL;
3955                 else if (declaration->modifiers & DM_STDCALL)
3956                         type->function.calling_convention = CC_STDCALL;
3957                 else if (declaration->modifiers & DM_FASTCALL)
3958                         type->function.calling_convention = CC_FASTCALL;
3959                 else if (declaration->modifiers & DM_THISCALL)
3960                         type->function.calling_convention = CC_THISCALL;
3961         } else {
3962                 type = allocate_type_zero(TYPE_FUNCTION, HERE);
3963         }
3964
3965         declaration_t *parameters = parse_parameters(&type->function);
3966         if (declaration != NULL) {
3967                 declaration->scope.declarations = parameters;
3968         }
3969
3970         construct_function_type_t *construct_function_type =
3971                 obstack_alloc(&temp_obst, sizeof(construct_function_type[0]));
3972         memset(construct_function_type, 0, sizeof(construct_function_type[0]));
3973         construct_function_type->construct_type.kind = CONSTRUCT_FUNCTION;
3974         construct_function_type->function_type       = type;
3975
3976         return &construct_function_type->construct_type;
3977 }
3978
3979 static void fix_declaration_type(declaration_t *declaration)
3980 {
3981         decl_modifiers_t declaration_modifiers = declaration->modifiers;
3982         type_modifiers_t type_modifiers        = declaration->type->base.modifiers;
3983
3984         if (declaration_modifiers & DM_TRANSPARENT_UNION)
3985                 type_modifiers |= TYPE_MODIFIER_TRANSPARENT_UNION;
3986
3987         if (declaration->type->base.modifiers == type_modifiers)
3988                 return;
3989
3990         type_t *copy = duplicate_type(declaration->type);
3991         copy->base.modifiers = type_modifiers;
3992
3993         type_t *result = typehash_insert(copy);
3994         if (result != copy) {
3995                 obstack_free(type_obst, copy);
3996         }
3997
3998         declaration->type = result;
3999 }
4000
4001 static construct_type_t *parse_inner_declarator(declaration_t *declaration,
4002                 bool may_be_abstract)
4003 {
4004         /* construct a single linked list of construct_type_t's which describe
4005          * how to construct the final declarator type */
4006         construct_type_t *first = NULL;
4007         construct_type_t *last  = NULL;
4008         gnu_attribute_t  *attributes = NULL;
4009
4010         decl_modifiers_t modifiers = parse_attributes(&attributes);
4011
4012         /* pointers */
4013         while (token.type == '*') {
4014                 construct_type_t *type = parse_pointer_declarator();
4015
4016                 if (last == NULL) {
4017                         first = type;
4018                         last  = type;
4019                 } else {
4020                         last->next = type;
4021                         last       = type;
4022                 }
4023
4024                 /* TODO: find out if this is correct */
4025                 modifiers |= parse_attributes(&attributes);
4026         }
4027
4028         if (declaration != NULL)
4029                 declaration->modifiers |= modifiers;
4030
4031         construct_type_t *inner_types = NULL;
4032
4033         switch(token.type) {
4034         case T_IDENTIFIER:
4035                 if (declaration == NULL) {
4036                         errorf(HERE, "no identifier expected in typename");
4037                 } else {
4038                         declaration->symbol          = token.v.symbol;
4039                         declaration->source_position = token.source_position;
4040                 }
4041                 next_token();
4042                 break;
4043         case '(':
4044                 next_token();
4045                 add_anchor_token(')');
4046                 inner_types = parse_inner_declarator(declaration, may_be_abstract);
4047                 if (inner_types != NULL) {
4048                         /* All later declarators only modify the return type, not declaration */
4049                         declaration = NULL;
4050                 }
4051                 rem_anchor_token(')');
4052                 expect(')');
4053                 break;
4054         default:
4055                 if (may_be_abstract)
4056                         break;
4057                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
4058                 /* avoid a loop in the outermost scope, because eat_statement doesn't
4059                  * eat '}' */
4060                 if (token.type == '}' && current_function == NULL) {
4061                         next_token();
4062                 } else {
4063                         eat_statement();
4064                 }
4065                 return NULL;
4066         }
4067
4068         construct_type_t *p = last;
4069
4070         while(true) {
4071                 construct_type_t *type;
4072                 switch(token.type) {
4073                 case '(':
4074                         type = parse_function_declarator(declaration);
4075                         break;
4076                 case '[':
4077                         type = parse_array_declarator();
4078                         break;
4079                 default:
4080                         goto declarator_finished;
4081                 }
4082
4083                 /* insert in the middle of the list (behind p) */
4084                 if (p != NULL) {
4085                         type->next = p->next;
4086                         p->next    = type;
4087                 } else {
4088                         type->next = first;
4089                         first      = type;
4090                 }
4091                 if (last == p) {
4092                         last = type;
4093                 }
4094         }
4095
4096 declarator_finished:
4097         /* append inner_types at the end of the list, we don't to set last anymore
4098          * as it's not needed anymore */
4099         if (last == NULL) {
4100                 assert(first == NULL);
4101                 first = inner_types;
4102         } else {
4103                 last->next = inner_types;
4104         }
4105
4106         return first;
4107 end_error:
4108         return NULL;
4109 }
4110
4111 static void parse_declaration_attributes(declaration_t *declaration)
4112 {
4113         gnu_attribute_t  *attributes = NULL;
4114         decl_modifiers_t  modifiers  = parse_attributes(&attributes);
4115
4116         if (declaration == NULL)
4117                 return;
4118
4119         declaration->modifiers |= modifiers;
4120         /* check if we have these stupid mode attributes... */
4121         type_t *old_type = declaration->type;
4122         if (old_type == NULL)
4123                 return;
4124
4125         gnu_attribute_t *attribute = attributes;
4126         for ( ; attribute != NULL; attribute = attribute->next) {
4127                 if (attribute->kind != GNU_AK_MODE || attribute->invalid)
4128                         continue;
4129
4130                 atomic_type_kind_t  akind = attribute->u.akind;
4131                 if (!is_type_signed(old_type)) {
4132                         switch(akind) {
4133                         case ATOMIC_TYPE_CHAR: akind = ATOMIC_TYPE_UCHAR; break;
4134                         case ATOMIC_TYPE_SHORT: akind = ATOMIC_TYPE_USHORT; break;
4135                         case ATOMIC_TYPE_INT: akind = ATOMIC_TYPE_UINT; break;
4136                         case ATOMIC_TYPE_LONGLONG: akind = ATOMIC_TYPE_ULONGLONG; break;
4137                         default:
4138                                 panic("invalid akind in mode attribute");
4139                         }
4140                 }
4141                 declaration->type
4142                         = make_atomic_type(akind, old_type->base.qualifiers);
4143         }
4144 }
4145
4146 static type_t *construct_declarator_type(construct_type_t *construct_list,
4147                                          type_t *type)
4148 {
4149         construct_type_t *iter = construct_list;
4150         for( ; iter != NULL; iter = iter->next) {
4151                 switch(iter->kind) {
4152                 case CONSTRUCT_INVALID:
4153                         internal_errorf(HERE, "invalid type construction found");
4154                 case CONSTRUCT_FUNCTION: {
4155                         construct_function_type_t *construct_function_type
4156                                 = (construct_function_type_t*) iter;
4157
4158                         type_t *function_type = construct_function_type->function_type;
4159
4160                         function_type->function.return_type = type;
4161
4162                         type_t *skipped_return_type = skip_typeref(type);
4163                         /* §6.7.5.3(1) */
4164                         if (is_type_function(skipped_return_type)) {
4165                                 errorf(HERE, "function returning function is not allowed");
4166                         } else if (is_type_array(skipped_return_type)) {
4167                                 errorf(HERE, "function returning array is not allowed");
4168                         } else {
4169                                 if (skipped_return_type->base.qualifiers != 0) {
4170                                         warningf(HERE,
4171                                                 "type qualifiers in return type of function type are meaningless");
4172                                 }
4173                         }
4174
4175                         type = function_type;
4176                         break;
4177                 }
4178
4179                 case CONSTRUCT_POINTER: {
4180                         parsed_pointer_t *parsed_pointer = (parsed_pointer_t*) iter;
4181                         type_t           *pointer_type   = allocate_type_zero(TYPE_POINTER, &null_position);
4182                         pointer_type->pointer.points_to  = type;
4183                         pointer_type->base.qualifiers    = parsed_pointer->type_qualifiers;
4184
4185                         type = pointer_type;
4186                         break;
4187                 }
4188
4189                 case CONSTRUCT_ARRAY: {
4190                         parsed_array_t *parsed_array  = (parsed_array_t*) iter;
4191                         type_t         *array_type    = allocate_type_zero(TYPE_ARRAY, &null_position);
4192
4193                         expression_t *size_expression = parsed_array->size;
4194                         if (size_expression != NULL) {
4195                                 size_expression
4196                                         = create_implicit_cast(size_expression, type_size_t);
4197                         }
4198
4199                         array_type->base.qualifiers       = parsed_array->type_qualifiers;
4200                         array_type->array.element_type    = type;
4201                         array_type->array.is_static       = parsed_array->is_static;
4202                         array_type->array.is_variable     = parsed_array->is_variable;
4203                         array_type->array.size_expression = size_expression;
4204
4205                         if (size_expression != NULL) {
4206                                 if (is_constant_expression(size_expression)) {
4207                                         array_type->array.size_constant = true;
4208                                         array_type->array.size
4209                                                 = fold_constant(size_expression);
4210                                 } else {
4211                                         array_type->array.is_vla = true;
4212                                 }
4213                         }
4214
4215                         type_t *skipped_type = skip_typeref(type);
4216                         /* §6.7.5.2(1) */
4217                         if (is_type_incomplete(skipped_type)) {
4218                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
4219                         } else if (is_type_function(skipped_type)) {
4220                                 errorf(HERE, "array of functions is not allowed");
4221                         }
4222                         type = array_type;
4223                         break;
4224                 }
4225                 }
4226
4227                 type_t *hashed_type = typehash_insert(type);
4228                 if (hashed_type != type) {
4229                         /* the function type was constructed earlier freeing it here will
4230                          * destroy other types... */
4231                         if (iter->kind != CONSTRUCT_FUNCTION) {
4232                                 free_type(type);
4233                         }
4234                         type = hashed_type;
4235                 }
4236         }
4237
4238         return type;
4239 }
4240
4241 static declaration_t *parse_declarator(
4242                 const declaration_specifiers_t *specifiers, bool may_be_abstract)
4243 {
4244         declaration_t *const declaration    = allocate_declaration_zero();
4245         declaration->source_position        = specifiers->source_position;
4246         declaration->declared_storage_class = specifiers->declared_storage_class;
4247         declaration->modifiers              = specifiers->modifiers;
4248         declaration->deprecated_string      = specifiers->deprecated_string;
4249         declaration->get_property_sym       = specifiers->get_property_sym;
4250         declaration->put_property_sym       = specifiers->put_property_sym;
4251         declaration->is_inline              = specifiers->is_inline;
4252
4253         declaration->storage_class          = specifiers->declared_storage_class;
4254         if (declaration->storage_class == STORAGE_CLASS_NONE
4255                         && scope != global_scope) {
4256                 declaration->storage_class = STORAGE_CLASS_AUTO;
4257         }
4258
4259         if (specifiers->alignment != 0) {
4260                 /* TODO: add checks here */
4261                 declaration->alignment = specifiers->alignment;
4262         }
4263
4264         construct_type_t *construct_type
4265                 = parse_inner_declarator(declaration, may_be_abstract);
4266         type_t *const type = specifiers->type;
4267         declaration->type = construct_declarator_type(construct_type, type);
4268
4269         parse_declaration_attributes(declaration);
4270
4271         fix_declaration_type(declaration);
4272
4273         if (construct_type != NULL) {
4274                 obstack_free(&temp_obst, construct_type);
4275         }
4276
4277         return declaration;
4278 }
4279
4280 static type_t *parse_abstract_declarator(type_t *base_type)
4281 {
4282         construct_type_t *construct_type = parse_inner_declarator(NULL, 1);
4283
4284         type_t *result = construct_declarator_type(construct_type, base_type);
4285         if (construct_type != NULL) {
4286                 obstack_free(&temp_obst, construct_type);
4287         }
4288
4289         return result;
4290 }
4291
4292 static declaration_t *append_declaration(declaration_t* const declaration)
4293 {
4294         if (last_declaration != NULL) {
4295                 last_declaration->next = declaration;
4296         } else {
4297                 scope->declarations = declaration;
4298         }
4299         last_declaration = declaration;
4300         return declaration;
4301 }
4302
4303 /**
4304  * Check if the declaration of main is suspicious.  main should be a
4305  * function with external linkage, returning int, taking either zero
4306  * arguments, two, or three arguments of appropriate types, ie.
4307  *
4308  * int main([ int argc, char **argv [, char **env ] ]).
4309  *
4310  * @param decl    the declaration to check
4311  * @param type    the function type of the declaration
4312  */
4313 static void check_type_of_main(const declaration_t *const decl, const function_type_t *const func_type)
4314 {
4315         if (decl->storage_class == STORAGE_CLASS_STATIC) {
4316                 warningf(&decl->source_position,
4317                          "'main' is normally a non-static function");
4318         }
4319         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4320                 warningf(&decl->source_position,
4321                          "return type of 'main' should be 'int', but is '%T'",
4322                          func_type->return_type);
4323         }
4324         const function_parameter_t *parm = func_type->parameters;
4325         if (parm != NULL) {
4326                 type_t *const first_type = parm->type;
4327                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4328                         warningf(&decl->source_position,
4329                                  "first argument of 'main' should be 'int', but is '%T'", first_type);
4330                 }
4331                 parm = parm->next;
4332                 if (parm != NULL) {
4333                         type_t *const second_type = parm->type;
4334                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4335                                 warningf(&decl->source_position,
4336                                          "second argument of 'main' should be 'char**', but is '%T'", second_type);
4337                         }
4338                         parm = parm->next;
4339                         if (parm != NULL) {
4340                                 type_t *const third_type = parm->type;
4341                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4342                                         warningf(&decl->source_position,
4343                                                  "third argument of 'main' should be 'char**', but is '%T'", third_type);
4344                                 }
4345                                 parm = parm->next;
4346                                 if (parm != NULL)
4347                                         goto warn_arg_count;
4348                         }
4349                 } else {
4350 warn_arg_count:
4351                         warningf(&decl->source_position, "'main' takes only zero, two or three arguments");
4352                 }
4353         }
4354 }
4355
4356 /**
4357  * Check if a symbol is the equal to "main".
4358  */
4359 static bool is_sym_main(const symbol_t *const sym)
4360 {
4361         return strcmp(sym->string, "main") == 0;
4362 }
4363
4364 static declaration_t *record_declaration(
4365         declaration_t *const declaration,
4366         const bool is_definition)
4367 {
4368         const symbol_t *const symbol  = declaration->symbol;
4369         const namespace_t     namespc = (namespace_t)declaration->namespc;
4370
4371         assert(symbol != NULL);
4372         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4373
4374         type_t *const orig_type = declaration->type;
4375         type_t *const type      = skip_typeref(orig_type);
4376         if (is_type_function(type) &&
4377                         type->function.unspecified_parameters &&
4378                         warning.strict_prototypes &&
4379                         previous_declaration == NULL) {
4380                 warningf(&declaration->source_position,
4381                          "function declaration '%#T' is not a prototype",
4382                          orig_type, declaration->symbol);
4383         }
4384
4385         if (warning.main && is_type_function(type) && is_sym_main(symbol)) {
4386                 check_type_of_main(declaration, &type->function);
4387         }
4388
4389         if (warning.nested_externs                             &&
4390             declaration->storage_class == STORAGE_CLASS_EXTERN &&
4391             scope                      != global_scope) {
4392                 warningf(&declaration->source_position,
4393                          "nested extern declaration of '%#T'", declaration->type, symbol);
4394         }
4395
4396         assert(declaration != previous_declaration);
4397         if (previous_declaration != NULL
4398                         && previous_declaration->parent_scope == scope) {
4399                 /* can happen for K&R style declarations */
4400                 if (previous_declaration->type == NULL) {
4401                         previous_declaration->type = declaration->type;
4402                 }
4403
4404                 const type_t *prev_type = skip_typeref(previous_declaration->type);
4405                 if (!types_compatible(type, prev_type)) {
4406                         errorf(&declaration->source_position,
4407                                    "declaration '%#T' is incompatible with '%#T' (declared %P)",
4408                                    orig_type, symbol, previous_declaration->type, symbol,
4409                                    &previous_declaration->source_position);
4410                 } else {
4411                         unsigned old_storage_class = previous_declaration->storage_class;
4412                         if (old_storage_class == STORAGE_CLASS_ENUM_ENTRY) {
4413                                 errorf(&declaration->source_position,
4414                                            "redeclaration of enum entry '%Y' (declared %P)",
4415                                            symbol, &previous_declaration->source_position);
4416                                 return previous_declaration;
4417                         }
4418
4419                         if (warning.redundant_decls                                     &&
4420                             is_definition                                               &&
4421                             previous_declaration->storage_class == STORAGE_CLASS_STATIC &&
4422                             !(previous_declaration->modifiers & DM_USED)                &&
4423                             !previous_declaration->used) {
4424                                 warningf(&previous_declaration->source_position,
4425                                          "unnecessary static forward declaration for '%#T'",
4426                                          previous_declaration->type, symbol);
4427                         }
4428
4429                         unsigned new_storage_class = declaration->storage_class;
4430
4431                         if (is_type_incomplete(prev_type)) {
4432                                 previous_declaration->type = type;
4433                                 prev_type                  = type;
4434                         }
4435
4436                         /* pretend no storage class means extern for function
4437                          * declarations (except if the previous declaration is neither
4438                          * none nor extern) */
4439                         if (is_type_function(type)) {
4440                                 if (prev_type->function.unspecified_parameters) {
4441                                         previous_declaration->type = type;
4442                                         prev_type                  = type;
4443                                 }
4444
4445                                 switch (old_storage_class) {
4446                                 case STORAGE_CLASS_NONE:
4447                                         old_storage_class = STORAGE_CLASS_EXTERN;
4448                                         /* FALLTHROUGH */
4449
4450                                 case STORAGE_CLASS_EXTERN:
4451                                         if (is_definition) {
4452                                                 if (warning.missing_prototypes &&
4453                                                     prev_type->function.unspecified_parameters &&
4454                                                     !is_sym_main(symbol)) {
4455                                                         warningf(&declaration->source_position,
4456                                                                          "no previous prototype for '%#T'",
4457                                                                          orig_type, symbol);
4458                                                 }
4459                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4460                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4461                                         }
4462                                         break;
4463
4464                                 default:
4465                                         break;
4466                                 }
4467                         }
4468
4469                         if (old_storage_class == STORAGE_CLASS_EXTERN &&
4470                                         new_storage_class == STORAGE_CLASS_EXTERN) {
4471 warn_redundant_declaration:
4472                                 if (!is_definition           &&
4473                                     warning.redundant_decls  &&
4474                                     is_type_valid(prev_type) &&
4475                                     strcmp(previous_declaration->source_position.input_name, "<builtin>") != 0) {
4476                                         warningf(&declaration->source_position,
4477                                                  "redundant declaration for '%Y' (declared %P)",
4478                                                  symbol, &previous_declaration->source_position);
4479                                 }
4480                         } else if (current_function == NULL) {
4481                                 if (old_storage_class != STORAGE_CLASS_STATIC &&
4482                                     new_storage_class == STORAGE_CLASS_STATIC) {
4483                                         errorf(&declaration->source_position,
4484                                                "static declaration of '%Y' follows non-static declaration (declared %P)",
4485                                                symbol, &previous_declaration->source_position);
4486                                 } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4487                                         previous_declaration->storage_class          = STORAGE_CLASS_NONE;
4488                                         previous_declaration->declared_storage_class = STORAGE_CLASS_NONE;
4489                                 } else {
4490                                         goto warn_redundant_declaration;
4491                                 }
4492                         } else if (is_type_valid(prev_type)) {
4493                                 if (old_storage_class == new_storage_class) {
4494                                         errorf(&declaration->source_position,
4495                                                "redeclaration of '%Y' (declared %P)",
4496                                                symbol, &previous_declaration->source_position);
4497                                 } else {
4498                                         errorf(&declaration->source_position,
4499                                                "redeclaration of '%Y' with different linkage (declared %P)",
4500                                                symbol, &previous_declaration->source_position);
4501                                 }
4502                         }
4503                 }
4504
4505                 previous_declaration->modifiers |= declaration->modifiers;
4506                 previous_declaration->is_inline |= declaration->is_inline;
4507                 return previous_declaration;
4508         } else if (is_type_function(type)) {
4509                 if (is_definition &&
4510                     declaration->storage_class != STORAGE_CLASS_STATIC) {
4511                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4512                                 warningf(&declaration->source_position,
4513                                          "no previous prototype for '%#T'", orig_type, symbol);
4514                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4515                                 warningf(&declaration->source_position,
4516                                          "no previous declaration for '%#T'", orig_type,
4517                                          symbol);
4518                         }
4519                 }
4520         } else {
4521                 if (warning.missing_declarations &&
4522                     scope == global_scope && (
4523                       declaration->storage_class == STORAGE_CLASS_NONE ||
4524                       declaration->storage_class == STORAGE_CLASS_THREAD
4525                     )) {
4526                         warningf(&declaration->source_position,
4527                                  "no previous declaration for '%#T'", orig_type, symbol);
4528                 }
4529         }
4530
4531         assert(declaration->parent_scope == NULL);
4532         assert(scope != NULL);
4533
4534         declaration->parent_scope = scope;
4535
4536         environment_push(declaration);
4537         return append_declaration(declaration);
4538 }
4539
4540 static void parser_error_multiple_definition(declaration_t *declaration,
4541                 const source_position_t *source_position)
4542 {
4543         errorf(source_position, "multiple definition of symbol '%Y' (declared %P)",
4544                declaration->symbol, &declaration->source_position);
4545 }
4546
4547 static bool is_declaration_specifier(const token_t *token,
4548                                      bool only_specifiers_qualifiers)
4549 {
4550         switch(token->type) {
4551                 TYPE_SPECIFIERS
4552                 TYPE_QUALIFIERS
4553                         return true;
4554                 case T_IDENTIFIER:
4555                         return is_typedef_symbol(token->v.symbol);
4556
4557                 case T___extension__:
4558                 STORAGE_CLASSES
4559                         return !only_specifiers_qualifiers;
4560
4561                 default:
4562                         return false;
4563         }
4564 }
4565
4566 static void parse_init_declarator_rest(declaration_t *declaration)
4567 {
4568         eat('=');
4569
4570         type_t *orig_type = declaration->type;
4571         type_t *type      = skip_typeref(orig_type);
4572
4573         if (declaration->init.initializer != NULL) {
4574                 parser_error_multiple_definition(declaration, HERE);
4575         }
4576
4577         bool must_be_constant = false;
4578         if (declaration->storage_class == STORAGE_CLASS_STATIC
4579                         || declaration->storage_class == STORAGE_CLASS_THREAD_STATIC
4580                         || declaration->parent_scope == global_scope) {
4581                 must_be_constant = true;
4582         }
4583
4584         if (is_type_function(type)) {
4585                 errorf(&declaration->source_position,
4586                        "function '%#T' is initialized like a variable",
4587                        orig_type, declaration->symbol);
4588                 orig_type = type_error_type;
4589         }
4590
4591         parse_initializer_env_t env;
4592         env.type             = orig_type;
4593         env.must_be_constant = must_be_constant;
4594         env.declaration      = current_init_decl = declaration;
4595
4596         initializer_t *initializer = parse_initializer(&env);
4597         current_init_decl = NULL;
4598
4599         if (!is_type_function(type)) {
4600                 /* § 6.7.5 (22)  array initializers for arrays with unknown size determine
4601                  * the array type size */
4602                 declaration->type             = env.type;
4603                 declaration->init.initializer = initializer;
4604         }
4605 }
4606
4607 /* parse rest of a declaration without any declarator */
4608 static void parse_anonymous_declaration_rest(
4609                 const declaration_specifiers_t *specifiers)
4610 {
4611         eat(';');
4612
4613         declaration_t *const declaration    = allocate_declaration_zero();
4614         declaration->type                   = specifiers->type;
4615         declaration->declared_storage_class = specifiers->declared_storage_class;
4616         declaration->source_position        = specifiers->source_position;
4617         declaration->modifiers              = specifiers->modifiers;
4618
4619         if (declaration->declared_storage_class != STORAGE_CLASS_NONE) {
4620                 warningf(&declaration->source_position,
4621                          "useless storage class in empty declaration");
4622         }
4623         declaration->storage_class = STORAGE_CLASS_NONE;
4624
4625         type_t *type = declaration->type;
4626         switch (type->kind) {
4627                 case TYPE_COMPOUND_STRUCT:
4628                 case TYPE_COMPOUND_UNION: {
4629                         if (type->compound.declaration->symbol == NULL) {
4630                                 warningf(&declaration->source_position,
4631                                          "unnamed struct/union that defines no instances");
4632                         }
4633                         break;
4634                 }
4635
4636                 case TYPE_ENUM:
4637                         break;
4638
4639                 default:
4640                         warningf(&declaration->source_position, "empty declaration");
4641                         break;
4642         }
4643
4644         append_declaration(declaration);
4645 }
4646
4647 static void parse_declaration_rest(declaration_t *ndeclaration,
4648                 const declaration_specifiers_t *specifiers,
4649                 parsed_declaration_func finished_declaration)
4650 {
4651         add_anchor_token(';');
4652         add_anchor_token('=');
4653         add_anchor_token(',');
4654         while(true) {
4655                 declaration_t *declaration =
4656                         finished_declaration(ndeclaration, token.type == '=');
4657
4658                 type_t *orig_type = declaration->type;
4659                 type_t *type      = skip_typeref(orig_type);
4660
4661                 if (type->kind != TYPE_FUNCTION &&
4662                     declaration->is_inline &&
4663                     is_type_valid(type)) {
4664                         warningf(&declaration->source_position,
4665                                  "variable '%Y' declared 'inline'\n", declaration->symbol);
4666                 }
4667
4668                 if (token.type == '=') {
4669                         parse_init_declarator_rest(declaration);
4670                 }
4671
4672                 if (token.type != ',')
4673                         break;
4674                 eat(',');
4675
4676                 ndeclaration = parse_declarator(specifiers, /*may_be_abstract=*/false);
4677         }
4678         expect(';');
4679
4680 end_error:
4681         rem_anchor_token(';');
4682         rem_anchor_token('=');
4683         rem_anchor_token(',');
4684 }
4685
4686 static declaration_t *finished_kr_declaration(declaration_t *declaration, bool is_definition)
4687 {
4688         symbol_t *symbol  = declaration->symbol;
4689         if (symbol == NULL) {
4690                 errorf(HERE, "anonymous declaration not valid as function parameter");
4691                 return declaration;
4692         }
4693         namespace_t namespc = (namespace_t) declaration->namespc;
4694         if (namespc != NAMESPACE_NORMAL) {
4695                 return record_declaration(declaration, false);
4696         }
4697
4698         declaration_t *previous_declaration = get_declaration(symbol, namespc);
4699         if (previous_declaration == NULL ||
4700                         previous_declaration->parent_scope != scope) {
4701                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4702                        symbol);
4703                 return declaration;
4704         }
4705
4706         if (is_definition) {
4707                 errorf(HERE, "parameter %Y is initialised", declaration->symbol);
4708         }
4709
4710         if (previous_declaration->type == NULL) {
4711                 previous_declaration->type          = declaration->type;
4712                 previous_declaration->declared_storage_class = declaration->declared_storage_class;
4713                 previous_declaration->storage_class = declaration->storage_class;
4714                 previous_declaration->parent_scope  = scope;
4715                 return previous_declaration;
4716         } else {
4717                 return record_declaration(declaration, false);
4718         }
4719 }
4720
4721 static void parse_declaration(parsed_declaration_func finished_declaration)
4722 {
4723         declaration_specifiers_t specifiers;
4724         memset(&specifiers, 0, sizeof(specifiers));
4725         parse_declaration_specifiers(&specifiers);
4726
4727         if (token.type == ';') {
4728                 parse_anonymous_declaration_rest(&specifiers);
4729         } else {
4730                 declaration_t *declaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
4731                 parse_declaration_rest(declaration, &specifiers, finished_declaration);
4732         }
4733 }
4734
4735 static type_t *get_default_promoted_type(type_t *orig_type)
4736 {
4737         type_t *result = orig_type;
4738
4739         type_t *type = skip_typeref(orig_type);
4740         if (is_type_integer(type)) {
4741                 result = promote_integer(type);
4742         } else if (type == type_float) {
4743                 result = type_double;
4744         }
4745
4746         return result;
4747 }
4748
4749 static void parse_kr_declaration_list(declaration_t *declaration)
4750 {
4751         type_t *type = skip_typeref(declaration->type);
4752         if (!is_type_function(type))
4753                 return;
4754
4755         if (!type->function.kr_style_parameters)
4756                 return;
4757
4758         /* push function parameters */
4759         int       top        = environment_top();
4760         scope_t  *last_scope = scope;
4761         set_scope(&declaration->scope);
4762
4763         declaration_t *parameter = declaration->scope.declarations;
4764         for ( ; parameter != NULL; parameter = parameter->next) {
4765                 assert(parameter->parent_scope == NULL);
4766                 parameter->parent_scope = scope;
4767                 environment_push(parameter);
4768         }
4769
4770         /* parse declaration list */
4771         while (is_declaration_specifier(&token, false)) {
4772                 parse_declaration(finished_kr_declaration);
4773         }
4774
4775         /* pop function parameters */
4776         assert(scope == &declaration->scope);
4777         set_scope(last_scope);
4778         environment_pop_to(top);
4779
4780         /* update function type */
4781         type_t *new_type = duplicate_type(type);
4782
4783         function_parameter_t *parameters     = NULL;
4784         function_parameter_t *last_parameter = NULL;
4785
4786         declaration_t *parameter_declaration = declaration->scope.declarations;
4787         for( ; parameter_declaration != NULL;
4788                         parameter_declaration = parameter_declaration->next) {
4789                 type_t *parameter_type = parameter_declaration->type;
4790                 if (parameter_type == NULL) {
4791                         if (strict_mode) {
4792                                 errorf(HERE, "no type specified for function parameter '%Y'",
4793                                        parameter_declaration->symbol);
4794                         } else {
4795                                 if (warning.implicit_int) {
4796                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
4797                                                 parameter_declaration->symbol);
4798                                 }
4799                                 parameter_type              = type_int;
4800                                 parameter_declaration->type = parameter_type;
4801                         }
4802                 }
4803
4804                 semantic_parameter(parameter_declaration);
4805                 parameter_type = parameter_declaration->type;
4806
4807                 /*
4808                  * we need the default promoted types for the function type
4809                  */
4810                 parameter_type = get_default_promoted_type(parameter_type);
4811
4812                 function_parameter_t *function_parameter
4813                         = obstack_alloc(type_obst, sizeof(function_parameter[0]));
4814                 memset(function_parameter, 0, sizeof(function_parameter[0]));
4815
4816                 function_parameter->type = parameter_type;
4817                 if (last_parameter != NULL) {
4818                         last_parameter->next = function_parameter;
4819                 } else {
4820                         parameters = function_parameter;
4821                 }
4822                 last_parameter = function_parameter;
4823         }
4824
4825         /* § 6.9.1.7: A K&R style parameter list does NOT act as a function
4826          * prototype */
4827         new_type->function.parameters             = parameters;
4828         new_type->function.unspecified_parameters = true;
4829
4830         type = typehash_insert(new_type);
4831         if (type != new_type) {
4832                 obstack_free(type_obst, new_type);
4833         }
4834
4835         declaration->type = type;
4836 }
4837
4838 static bool first_err = true;
4839
4840 /**
4841  * When called with first_err set, prints the name of the current function,
4842  * else does noting.
4843  */
4844 static void print_in_function(void)
4845 {
4846         if (first_err) {
4847                 first_err = false;
4848                 diagnosticf("%s: In function '%Y':\n",
4849                         current_function->source_position.input_name,
4850                         current_function->symbol);
4851         }
4852 }
4853
4854 /**
4855  * Check if all labels are defined in the current function.
4856  * Check if all labels are used in the current function.
4857  */
4858 static void check_labels(void)
4859 {
4860         for (const goto_statement_t *goto_statement = goto_first;
4861             goto_statement != NULL;
4862             goto_statement = goto_statement->next) {
4863                 /* skip computed gotos */
4864                 if (goto_statement->expression != NULL)
4865                         continue;
4866
4867                 declaration_t *label = goto_statement->label;
4868
4869                 label->used = true;
4870                 if (label->source_position.input_name == NULL) {
4871                         print_in_function();
4872                         errorf(&goto_statement->base.source_position,
4873                                "label '%Y' used but not defined", label->symbol);
4874                  }
4875         }
4876         goto_first = goto_last = NULL;
4877
4878         if (warning.unused_label) {
4879                 for (const label_statement_t *label_statement = label_first;
4880                          label_statement != NULL;
4881                          label_statement = label_statement->next) {
4882                         const declaration_t *label = label_statement->label;
4883
4884                         if (! label->used) {
4885                                 print_in_function();
4886                                 warningf(&label_statement->base.source_position,
4887                                         "label '%Y' defined but not used", label->symbol);
4888                         }
4889                 }
4890         }
4891         label_first = label_last = NULL;
4892 }
4893
4894 /**
4895  * Check declarations of current_function for unused entities.
4896  */
4897 static void check_declarations(void)
4898 {
4899         if (warning.unused_parameter) {
4900                 const scope_t *scope = &current_function->scope;
4901
4902                 if (is_sym_main(current_function->symbol)) {
4903                         /* do not issue unused warnings for main */
4904                         return;
4905                 }
4906                 const declaration_t *parameter = scope->declarations;
4907                 for (; parameter != NULL; parameter = parameter->next) {
4908                         if (! parameter->used) {
4909                                 print_in_function();
4910                                 warningf(&parameter->source_position,
4911                                          "unused parameter '%Y'", parameter->symbol);
4912                         }
4913                 }
4914         }
4915         if (warning.unused_variable) {
4916         }
4917 }
4918
4919 static int determine_truth(expression_t const* const cond)
4920 {
4921         return
4922                 !is_constant_expression(cond) ? 0 :
4923                 fold_constant(cond) != 0      ? 1 :
4924                 -1;
4925 }
4926
4927 static bool noreturn_candidate;
4928
4929 static void check_reachable(statement_t *const stmt)
4930 {
4931         if (stmt->base.reachable)
4932                 return;
4933         if (stmt->kind != STATEMENT_DO_WHILE)
4934                 stmt->base.reachable = true;
4935
4936         statement_t *last = stmt;
4937         statement_t *next;
4938         switch (stmt->kind) {
4939                 case STATEMENT_INVALID:
4940                 case STATEMENT_EMPTY:
4941                 case STATEMENT_DECLARATION:
4942                 case STATEMENT_ASM:
4943                         next = stmt->base.next;
4944                         break;
4945
4946                 case STATEMENT_COMPOUND:
4947                         next = stmt->compound.statements;
4948                         break;
4949
4950                 case STATEMENT_RETURN:
4951                         noreturn_candidate = false;
4952                         return;
4953
4954                 case STATEMENT_IF: {
4955                         if_statement_t const* const ifs = &stmt->ifs;
4956                         int            const        val = determine_truth(ifs->condition);
4957
4958                         if (val >= 0)
4959                                 check_reachable(ifs->true_statement);
4960
4961                         if (val > 0)
4962                                 return;
4963
4964                         if (ifs->false_statement != NULL) {
4965                                 check_reachable(ifs->false_statement);
4966                                 return;
4967                         }
4968
4969                         next = stmt->base.next;
4970                         break;
4971                 }
4972
4973                 case STATEMENT_SWITCH: {
4974                         switch_statement_t const *const switchs = &stmt->switchs;
4975                         expression_t       const *const expr    = switchs->expression;
4976
4977                         if (is_constant_expression(expr)) {
4978                                 long                    const val      = fold_constant(expr);
4979                                 case_label_statement_t *      defaults = NULL;
4980                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4981                                         if (i->expression == NULL) {
4982                                                 defaults = i;
4983                                                 continue;
4984                                         }
4985
4986                                         if (i->first_case <= val && val <= i->last_case) {
4987                                                 check_reachable((statement_t*)i);
4988                                                 return;
4989                                         }
4990                                 }
4991
4992                                 if (defaults != NULL) {
4993                                         check_reachable((statement_t*)defaults);
4994                                         return;
4995                                 }
4996                         } else {
4997                                 bool has_default = false;
4998                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
4999                                         if (i->expression == NULL)
5000                                                 has_default = true;
5001
5002                                         check_reachable((statement_t*)i);
5003                                 }
5004
5005                                 if (has_default)
5006                                         return;
5007                         }
5008
5009                         next = stmt->base.next;
5010                         break;
5011                 }
5012
5013                 case STATEMENT_EXPRESSION: {
5014                         /* Check for noreturn function call */
5015                         expression_t const *const expr = stmt->expression.expression;
5016                         if (expr->kind == EXPR_CALL) {
5017                                 expression_t const *const func = expr->call.function;
5018                                 if (func->kind == EXPR_REFERENCE) {
5019                                         declaration_t const *const decl = func->reference.declaration;
5020                                         if (decl != NULL && decl->modifiers & DM_NORETURN) {
5021                                                 return;
5022                                         }
5023                                 }
5024                         }
5025
5026                         next = stmt->base.next;
5027                         break;
5028                 }
5029
5030                 case STATEMENT_CONTINUE: {
5031                         statement_t *parent = stmt;
5032                         for (;;) {
5033                                 parent = parent->base.parent;
5034                                 if (parent == NULL) /* continue not within loop */
5035                                         return;
5036
5037                                 next = parent;
5038                                 switch (parent->kind) {
5039                                         case STATEMENT_WHILE:    goto continue_while;
5040                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5041                                         case STATEMENT_FOR:      goto continue_for;
5042
5043                                         default: break;
5044                                 }
5045                         }
5046                 }
5047
5048                 case STATEMENT_BREAK: {
5049                         statement_t *parent = stmt;
5050                         for (;;) {
5051                                 parent = parent->base.parent;
5052                                 if (parent == NULL) /* break not within loop/switch */
5053                                         return;
5054
5055                                 switch (parent->kind) {
5056                                         case STATEMENT_SWITCH:
5057                                         case STATEMENT_WHILE:
5058                                         case STATEMENT_DO_WHILE:
5059                                         case STATEMENT_FOR:
5060                                                 last = parent;
5061                                                 next = parent->base.next;
5062                                                 goto found_break_parent;
5063
5064                                         default: break;
5065                                 }
5066                         }
5067 found_break_parent:
5068                         break;
5069                 }
5070
5071                 case STATEMENT_GOTO:
5072                         if (stmt->gotos.expression) {
5073                                 statement_t *parent = stmt->base.parent;
5074                                 if (parent == NULL) /* top level goto */
5075                                         return;
5076                                 next = parent;
5077                         } else {
5078                                 next = stmt->gotos.label->init.statement;
5079                                 if (next == NULL) /* missing label */
5080                                         return;
5081                         }
5082                         break;
5083
5084                 case STATEMENT_LABEL:
5085                         next = stmt->label.statement;
5086                         break;
5087
5088                 case STATEMENT_CASE_LABEL:
5089                         next = stmt->case_label.statement;
5090                         break;
5091
5092                 case STATEMENT_WHILE: {
5093                         while_statement_t const *const whiles = &stmt->whiles;
5094                         int                      const val    = determine_truth(whiles->condition);
5095
5096                         if (val >= 0)
5097                                 check_reachable(whiles->body);
5098
5099                         if (val > 0)
5100                                 return;
5101
5102                         next = stmt->base.next;
5103                         break;
5104                 }
5105
5106                 case STATEMENT_DO_WHILE:
5107                         next = stmt->do_while.body;
5108                         break;
5109
5110                 case STATEMENT_FOR: {
5111                         for_statement_t *const fors = &stmt->fors;
5112
5113                         if (fors->condition_reachable)
5114                                 return;
5115                         fors->condition_reachable = true;
5116
5117                         expression_t const *const cond = fors->condition;
5118                         int          const        val  =
5119                                 cond == NULL ? 1 : determine_truth(cond);
5120
5121                         if (val >= 0)
5122                                 check_reachable(fors->body);
5123
5124                         if (val > 0)
5125                                 return;
5126
5127                         next = stmt->base.next;
5128                         break;
5129                 }
5130
5131                 case STATEMENT_MS_TRY: {
5132                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5133                         check_reachable(ms_try->try_statement);
5134                         next = ms_try->final_statement;
5135                         break;
5136                 }
5137
5138                 case STATEMENT_LEAVE: {
5139                         statement_t *parent = stmt;
5140                         for (;;) {
5141                                 parent = parent->base.parent;
5142                                 if (parent == NULL) /* __leave not within __try */
5143                                         return;
5144
5145                                 if (parent->kind == STATEMENT_MS_TRY) {
5146                                         last = parent;
5147                                         next = parent->ms_try.final_statement;
5148                                         break;
5149                                 }
5150                         }
5151                         break;
5152                 }
5153         }
5154
5155         while (next == NULL) {
5156                 next = last->base.parent;
5157                 if (next == NULL) {
5158                         noreturn_candidate = false;
5159
5160                         type_t *const type = current_function->type;
5161                         assert(is_type_function(type));
5162                         type_t *const ret  = skip_typeref(type->function.return_type);
5163                         if (warning.return_type                    &&
5164                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
5165                             is_type_valid(ret)                     &&
5166                             !is_sym_main(current_function->symbol)) {
5167                                 warningf(&stmt->base.source_position,
5168                                          "control reaches end of non-void function");
5169                         }
5170                         return;
5171                 }
5172
5173                 switch (next->kind) {
5174                         case STATEMENT_INVALID:
5175                         case STATEMENT_EMPTY:
5176                         case STATEMENT_DECLARATION:
5177                         case STATEMENT_EXPRESSION:
5178                         case STATEMENT_ASM:
5179                         case STATEMENT_RETURN:
5180                         case STATEMENT_CONTINUE:
5181                         case STATEMENT_BREAK:
5182                         case STATEMENT_GOTO:
5183                         case STATEMENT_LEAVE:
5184                                 panic("invalid control flow in function");
5185
5186                         case STATEMENT_COMPOUND:
5187                         case STATEMENT_IF:
5188                         case STATEMENT_SWITCH:
5189                         case STATEMENT_LABEL:
5190                         case STATEMENT_CASE_LABEL:
5191                                 last = next;
5192                                 next = next->base.next;
5193                                 break;
5194
5195                         case STATEMENT_WHILE: {
5196 continue_while:
5197                                 if (next->base.reachable)
5198                                         return;
5199                                 next->base.reachable = true;
5200
5201                                 while_statement_t const *const whiles = &next->whiles;
5202                                 int                      const val    = determine_truth(whiles->condition);
5203
5204                                 if (val >= 0)
5205                                         check_reachable(whiles->body);
5206
5207                                 if (val > 0)
5208                                         return;
5209
5210                                 last = next;
5211                                 next = next->base.next;
5212                                 break;
5213                         }
5214
5215                         case STATEMENT_DO_WHILE: {
5216 continue_do_while:
5217                                 if (next->base.reachable)
5218                                         return;
5219                                 next->base.reachable = true;
5220
5221                                 do_while_statement_t const *const dw  = &next->do_while;
5222                                 int                  const        val = determine_truth(dw->condition);
5223
5224                                 if (val >= 0)
5225                                         check_reachable(dw->body);
5226
5227                                 if (val > 0)
5228                                         return;
5229
5230                                 last = next;
5231                                 next = next->base.next;
5232                                 break;
5233                         }
5234
5235                         case STATEMENT_FOR: {
5236 continue_for:;
5237                                 for_statement_t *const fors = &next->fors;
5238
5239                                 fors->step_reachable = true;
5240
5241                                 if (fors->condition_reachable)
5242                                         return;
5243                                 fors->condition_reachable = true;
5244
5245                                 expression_t const *const cond = fors->condition;
5246                                 int          const        val  =
5247                                         cond == NULL ? 1 : determine_truth(cond);
5248
5249                                 if (val >= 0)
5250                                         check_reachable(fors->body);
5251
5252                                 if (val > 0)
5253                                         return;
5254
5255                                 last = next;
5256                                 next = next->base.next;
5257                                 break;
5258                         }
5259
5260                         case STATEMENT_MS_TRY:
5261                                 last = next;
5262                                 next = next->ms_try.final_statement;
5263                                 break;
5264                 }
5265         }
5266
5267         if (next == NULL) {
5268                 next = stmt->base.parent;
5269                 if (next == NULL) {
5270                         warningf(&stmt->base.source_position,
5271                                  "control reaches end of non-void function");
5272                 }
5273         }
5274
5275         check_reachable(next);
5276 }
5277
5278 static void check_unreachable(statement_t const* const stmt)
5279 {
5280         if (!stmt->base.reachable            &&
5281             stmt->kind != STATEMENT_DO_WHILE &&
5282             stmt->kind != STATEMENT_FOR      &&
5283             (stmt->kind != STATEMENT_COMPOUND || stmt->compound.statements == NULL)) {
5284                 warningf(&stmt->base.source_position, "statement is unreachable");
5285         }
5286
5287         switch (stmt->kind) {
5288                 case STATEMENT_INVALID:
5289                 case STATEMENT_EMPTY:
5290                 case STATEMENT_RETURN:
5291                 case STATEMENT_DECLARATION:
5292                 case STATEMENT_EXPRESSION:
5293                 case STATEMENT_CONTINUE:
5294                 case STATEMENT_BREAK:
5295                 case STATEMENT_GOTO:
5296                 case STATEMENT_ASM:
5297                 case STATEMENT_LEAVE:
5298                         break;
5299
5300                 case STATEMENT_COMPOUND:
5301                         if (stmt->compound.statements)
5302                                 check_unreachable(stmt->compound.statements);
5303                         break;
5304
5305                 case STATEMENT_IF:
5306                         check_unreachable(stmt->ifs.true_statement);
5307                         if (stmt->ifs.false_statement != NULL)
5308                                 check_unreachable(stmt->ifs.false_statement);
5309                         break;
5310
5311                 case STATEMENT_SWITCH:
5312                         check_unreachable(stmt->switchs.body);
5313                         break;
5314
5315                 case STATEMENT_LABEL:
5316                         check_unreachable(stmt->label.statement);
5317                         break;
5318
5319                 case STATEMENT_CASE_LABEL:
5320                         check_unreachable(stmt->case_label.statement);
5321                         break;
5322
5323                 case STATEMENT_WHILE:
5324                         check_unreachable(stmt->whiles.body);
5325                         break;
5326
5327                 case STATEMENT_DO_WHILE:
5328                         check_unreachable(stmt->do_while.body);
5329                         if (!stmt->base.reachable) {
5330                                 expression_t const *const cond = stmt->do_while.condition;
5331                                 if (determine_truth(cond) >= 0) {
5332                                         warningf(&cond->base.source_position,
5333                                                  "condition of do-while-loop is unreachable");
5334                                 }
5335                         }
5336                         break;
5337
5338                 case STATEMENT_FOR: {
5339                         for_statement_t const* const fors = &stmt->fors;
5340
5341                         // if init and step are unreachable, cond is unreachable, too
5342                         if (!stmt->base.reachable && !fors->step_reachable) {
5343                                 warningf(&stmt->base.source_position, "statement is unreachable");
5344                         } else {
5345                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5346                                         warningf(&fors->initialisation->base.source_position,
5347                                                  "initialisation of for-statement is unreachable");
5348                                 }
5349
5350                                 if (!fors->condition_reachable && fors->condition != NULL) {
5351                                         warningf(&fors->condition->base.source_position,
5352                                                  "condition of for-statement is unreachable");
5353                                 }
5354
5355                                 if (!fors->step_reachable && fors->step != NULL) {
5356                                         warningf(&fors->step->base.source_position,
5357                                                  "step of for-statement is unreachable");
5358                                 }
5359                         }
5360
5361                         check_unreachable(fors->body);
5362                         break;
5363                 }
5364
5365                 case STATEMENT_MS_TRY: {
5366                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5367                         check_unreachable(ms_try->try_statement);
5368                         check_unreachable(ms_try->final_statement);
5369                 }
5370         }
5371
5372         if (stmt->base.next)
5373                 check_unreachable(stmt->base.next);
5374 }
5375
5376 static void parse_external_declaration(void)
5377 {
5378         /* function-definitions and declarations both start with declaration
5379          * specifiers */
5380         declaration_specifiers_t specifiers;
5381         memset(&specifiers, 0, sizeof(specifiers));
5382
5383         add_anchor_token(';');
5384         parse_declaration_specifiers(&specifiers);
5385         rem_anchor_token(';');
5386
5387         /* must be a declaration */
5388         if (token.type == ';') {
5389                 parse_anonymous_declaration_rest(&specifiers);
5390                 return;
5391         }
5392
5393         add_anchor_token(',');
5394         add_anchor_token('=');
5395         add_anchor_token(';');
5396
5397         /* declarator is common to both function-definitions and declarations */
5398         declaration_t *ndeclaration = parse_declarator(&specifiers, /*may_be_abstract=*/false);
5399
5400         rem_anchor_token(',');
5401         rem_anchor_token('=');
5402         rem_anchor_token(';');
5403
5404         /* must be a declaration */
5405         switch (token.type) {
5406                 case ',':
5407                 case ';':
5408                 case '=':
5409                         parse_declaration_rest(ndeclaration, &specifiers, record_declaration);
5410                         return;
5411         }
5412
5413         /* must be a function definition */
5414         parse_kr_declaration_list(ndeclaration);
5415
5416         if (token.type != '{') {
5417                 parse_error_expected("while parsing function definition", '{', NULL);
5418                 eat_until_matching_token(';');
5419                 return;
5420         }
5421
5422         type_t *type = ndeclaration->type;
5423
5424         /* note that we don't skip typerefs: the standard doesn't allow them here
5425          * (so we can't use is_type_function here) */
5426         if (type->kind != TYPE_FUNCTION) {
5427                 if (is_type_valid(type)) {
5428                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5429                                type, ndeclaration->symbol);
5430                 }
5431                 eat_block();
5432                 return;
5433         }
5434
5435         if (warning.aggregate_return &&
5436             is_type_compound(skip_typeref(type->function.return_type))) {
5437                 warningf(HERE, "function '%Y' returns an aggregate",
5438                          ndeclaration->symbol);
5439         }
5440         if (warning.traditional && !type->function.unspecified_parameters) {
5441                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
5442                         ndeclaration->symbol);
5443         }
5444         if (warning.old_style_definition && type->function.unspecified_parameters) {
5445                 warningf(HERE, "old-style function definition '%Y'",
5446                         ndeclaration->symbol);
5447         }
5448
5449         /* § 6.7.5.3 (14) a function definition with () means no
5450          * parameters (and not unspecified parameters) */
5451         if (type->function.unspecified_parameters
5452                         && type->function.parameters == NULL
5453                         && !type->function.kr_style_parameters) {
5454                 type_t *duplicate = duplicate_type(type);
5455                 duplicate->function.unspecified_parameters = false;
5456
5457                 type = typehash_insert(duplicate);
5458                 if (type != duplicate) {
5459                         obstack_free(type_obst, duplicate);
5460                 }
5461                 ndeclaration->type = type;
5462         }
5463
5464         declaration_t *const declaration = record_declaration(ndeclaration, true);
5465         if (ndeclaration != declaration) {
5466                 declaration->scope = ndeclaration->scope;
5467         }
5468         type = skip_typeref(declaration->type);
5469
5470         /* push function parameters and switch scope */
5471         int       top        = environment_top();
5472         scope_t  *last_scope = scope;
5473         set_scope(&declaration->scope);
5474
5475         declaration_t *parameter = declaration->scope.declarations;
5476         for( ; parameter != NULL; parameter = parameter->next) {
5477                 if (parameter->parent_scope == &ndeclaration->scope) {
5478                         parameter->parent_scope = scope;
5479                 }
5480                 assert(parameter->parent_scope == NULL
5481                                 || parameter->parent_scope == scope);
5482                 parameter->parent_scope = scope;
5483                 if (parameter->symbol == NULL) {
5484                         errorf(&parameter->source_position, "parameter name omitted");
5485                         continue;
5486                 }
5487                 environment_push(parameter);
5488         }
5489
5490         if (declaration->init.statement != NULL) {
5491                 parser_error_multiple_definition(declaration, HERE);
5492                 eat_block();
5493         } else {
5494                 /* parse function body */
5495                 int            label_stack_top      = label_top();
5496                 declaration_t *old_current_function = current_function;
5497                 current_function                    = declaration;
5498                 current_parent                      = NULL;
5499
5500                 statement_t *const body = parse_compound_statement(false);
5501                 declaration->init.statement = body;
5502                 first_err = true;
5503                 check_labels();
5504                 check_declarations();
5505                 if (warning.return_type      ||
5506                     warning.unreachable_code ||
5507                     (warning.missing_noreturn && !(declaration->modifiers & DM_NORETURN))) {
5508                         noreturn_candidate = true;
5509                         check_reachable(body);
5510                         if (warning.unreachable_code)
5511                                 check_unreachable(body);
5512                         if (warning.missing_noreturn &&
5513                             noreturn_candidate       &&
5514                             !(declaration->modifiers & DM_NORETURN)) {
5515                                 warningf(&body->base.source_position,
5516                                          "function '%#T' is candidate for attribute 'noreturn'",
5517                                          type, declaration->symbol);
5518                         }
5519                 }
5520
5521                 assert(current_parent   == NULL);
5522                 assert(current_function == declaration);
5523                 current_function = old_current_function;
5524                 label_pop_to(label_stack_top);
5525         }
5526
5527         assert(scope == &declaration->scope);
5528         set_scope(last_scope);
5529         environment_pop_to(top);
5530 }
5531
5532 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5533                                   source_position_t *source_position,
5534                                   const symbol_t *symbol)
5535 {
5536         type_t *type = allocate_type_zero(TYPE_BITFIELD, source_position);
5537
5538         type->bitfield.base_type       = base_type;
5539         type->bitfield.size_expression = size;
5540
5541         il_size_t bit_size;
5542         type_t *skipped_type = skip_typeref(base_type);
5543         if (!is_type_integer(skipped_type)) {
5544                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5545                         base_type);
5546                 bit_size = 0;
5547         } else {
5548                 bit_size = skipped_type->base.size * 8;
5549         }
5550
5551         if (is_constant_expression(size)) {
5552                 long v = fold_constant(size);
5553
5554                 if (v < 0) {
5555                         errorf(source_position, "negative width in bit-field '%Y'",
5556                                 symbol);
5557                 } else if (v == 0) {
5558                         errorf(source_position, "zero width for bit-field '%Y'",
5559                                 symbol);
5560                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
5561                         errorf(source_position, "width of '%Y' exceeds its type",
5562                                 symbol);
5563                 } else {
5564                         type->bitfield.bit_size = v;
5565                 }
5566         }
5567
5568         return type;
5569 }
5570
5571 static declaration_t *find_compound_entry(declaration_t *compound_declaration,
5572                                           symbol_t *symbol)
5573 {
5574         declaration_t *iter = compound_declaration->scope.declarations;
5575         for( ; iter != NULL; iter = iter->next) {
5576                 if (iter->namespc != NAMESPACE_NORMAL)
5577                         continue;
5578
5579                 if (iter->symbol == NULL) {
5580                         type_t *type = skip_typeref(iter->type);
5581                         if (is_type_compound(type)) {
5582                                 declaration_t *result
5583                                         = find_compound_entry(type->compound.declaration, symbol);
5584                                 if (result != NULL)
5585                                         return result;
5586                         }
5587                         continue;
5588                 }
5589
5590                 if (iter->symbol == symbol) {
5591                         return iter;
5592                 }
5593         }
5594
5595         return NULL;
5596 }
5597
5598 static void parse_compound_declarators(declaration_t *struct_declaration,
5599                 const declaration_specifiers_t *specifiers)
5600 {
5601         declaration_t *last_declaration = struct_declaration->scope.declarations;
5602         if (last_declaration != NULL) {
5603                 while (last_declaration->next != NULL) {
5604                         last_declaration = last_declaration->next;
5605                 }
5606         }
5607
5608         while (true) {
5609                 declaration_t *declaration;
5610
5611                 if (token.type == ':') {
5612                         source_position_t source_position = *HERE;
5613                         next_token();
5614
5615                         type_t *base_type = specifiers->type;
5616                         expression_t *size = parse_constant_expression();
5617
5618                         type_t *type = make_bitfield_type(base_type, size,
5619                                         &source_position, sym_anonymous);
5620
5621                         declaration                         = allocate_declaration_zero();
5622                         declaration->namespc                = NAMESPACE_NORMAL;
5623                         declaration->declared_storage_class = STORAGE_CLASS_NONE;
5624                         declaration->storage_class          = STORAGE_CLASS_NONE;
5625                         declaration->source_position        = source_position;
5626                         declaration->modifiers              = specifiers->modifiers;
5627                         declaration->type                   = type;
5628                 } else {
5629                         declaration = parse_declarator(specifiers,/*may_be_abstract=*/true);
5630
5631                         type_t *orig_type = declaration->type;
5632                         type_t *type      = skip_typeref(orig_type);
5633
5634                         if (token.type == ':') {
5635                                 source_position_t source_position = *HERE;
5636                                 next_token();
5637                                 expression_t *size = parse_constant_expression();
5638
5639                                 type_t *bitfield_type = make_bitfield_type(orig_type, size,
5640                                                 &source_position, declaration->symbol);
5641                                 declaration->type = bitfield_type;
5642                         } else {
5643                                 /* TODO we ignore arrays for now... what is missing is a check
5644                                  * that they're at the end of the struct */
5645                                 if (is_type_incomplete(type) && !is_type_array(type)) {
5646                                         errorf(HERE,
5647                                                "compound member '%Y' has incomplete type '%T'",
5648                                                declaration->symbol, orig_type);
5649                                 } else if (is_type_function(type)) {
5650                                         errorf(HERE, "compound member '%Y' must not have function type '%T'",
5651                                                declaration->symbol, orig_type);
5652                                 }
5653                         }
5654                 }
5655
5656                 /* make sure we don't define a symbol multiple times */
5657                 symbol_t *symbol = declaration->symbol;
5658                 if (symbol != NULL) {
5659                         declaration_t *prev_decl
5660                                 = find_compound_entry(struct_declaration, symbol);
5661
5662                         if (prev_decl != NULL) {
5663                                 assert(prev_decl->symbol == symbol);
5664                                 errorf(&declaration->source_position,
5665                                        "multiple declarations of symbol '%Y' (declared %P)",
5666                                        symbol, &prev_decl->source_position);
5667                         }
5668                 }
5669
5670                 /* append declaration */
5671                 if (last_declaration != NULL) {
5672                         last_declaration->next = declaration;
5673                 } else {
5674                         struct_declaration->scope.declarations = declaration;
5675                 }
5676                 last_declaration = declaration;
5677
5678                 if (token.type != ',')
5679                         break;
5680                 next_token();
5681         }
5682         expect(';');
5683
5684 end_error:
5685         ;
5686 }
5687
5688 static void parse_compound_type_entries(declaration_t *compound_declaration)
5689 {
5690         eat('{');
5691         add_anchor_token('}');
5692
5693         while (token.type != '}' && token.type != T_EOF) {
5694                 declaration_specifiers_t specifiers;
5695                 memset(&specifiers, 0, sizeof(specifiers));
5696                 parse_declaration_specifiers(&specifiers);
5697
5698                 parse_compound_declarators(compound_declaration, &specifiers);
5699         }
5700         rem_anchor_token('}');
5701
5702         if (token.type == T_EOF) {
5703                 errorf(HERE, "EOF while parsing struct");
5704         }
5705         next_token();
5706 }
5707
5708 static type_t *parse_typename(void)
5709 {
5710         declaration_specifiers_t specifiers;
5711         memset(&specifiers, 0, sizeof(specifiers));
5712         parse_declaration_specifiers(&specifiers);
5713         if (specifiers.declared_storage_class != STORAGE_CLASS_NONE) {
5714                 /* TODO: improve error message, user does probably not know what a
5715                  * storage class is...
5716                  */
5717                 errorf(HERE, "typename may not have a storage class");
5718         }
5719
5720         type_t *result = parse_abstract_declarator(specifiers.type);
5721
5722         return result;
5723 }
5724
5725
5726
5727
5728 typedef expression_t* (*parse_expression_function) (unsigned precedence);
5729 typedef expression_t* (*parse_expression_infix_function) (unsigned precedence,
5730                                                           expression_t *left);
5731
5732 typedef struct expression_parser_function_t expression_parser_function_t;
5733 struct expression_parser_function_t {
5734         unsigned                         precedence;
5735         parse_expression_function        parser;
5736         unsigned                         infix_precedence;
5737         parse_expression_infix_function  infix_parser;
5738 };
5739
5740 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5741
5742 /**
5743  * Prints an error message if an expression was expected but not read
5744  */
5745 static expression_t *expected_expression_error(void)
5746 {
5747         /* skip the error message if the error token was read */
5748         if (token.type != T_ERROR) {
5749                 errorf(HERE, "expected expression, got token '%K'", &token);
5750         }
5751         next_token();
5752
5753         return create_invalid_expression();
5754 }
5755
5756 /**
5757  * Parse a string constant.
5758  */
5759 static expression_t *parse_string_const(void)
5760 {
5761         wide_string_t wres;
5762         if (token.type == T_STRING_LITERAL) {
5763                 string_t res = token.v.string;
5764                 next_token();
5765                 while (token.type == T_STRING_LITERAL) {
5766                         res = concat_strings(&res, &token.v.string);
5767                         next_token();
5768                 }
5769                 if (token.type != T_WIDE_STRING_LITERAL) {
5770                         expression_t *const cnst = allocate_expression_zero(EXPR_STRING_LITERAL);
5771                         /* note: that we use type_char_ptr here, which is already the
5772                          * automatic converted type. revert_automatic_type_conversion
5773                          * will construct the array type */
5774                         cnst->base.type    = warning.write_strings ? type_const_char_ptr : type_char_ptr;
5775                         cnst->string.value = res;
5776                         return cnst;
5777                 }
5778
5779                 wres = concat_string_wide_string(&res, &token.v.wide_string);
5780         } else {
5781                 wres = token.v.wide_string;
5782         }
5783         next_token();
5784
5785         for (;;) {
5786                 switch (token.type) {
5787                         case T_WIDE_STRING_LITERAL:
5788                                 wres = concat_wide_strings(&wres, &token.v.wide_string);
5789                                 break;
5790
5791                         case T_STRING_LITERAL:
5792                                 wres = concat_wide_string_string(&wres, &token.v.string);
5793                                 break;
5794
5795                         default: {
5796                                 expression_t *const cnst = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
5797                                 cnst->base.type         = warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
5798                                 cnst->wide_string.value = wres;
5799                                 return cnst;
5800                         }
5801                 }
5802                 next_token();
5803         }
5804 }
5805
5806 /**
5807  * Parse an integer constant.
5808  */
5809 static expression_t *parse_int_const(void)
5810 {
5811         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5812         cnst->base.source_position = *HERE;
5813         cnst->base.type            = token.datatype;
5814         cnst->conste.v.int_value   = token.v.intvalue;
5815
5816         next_token();
5817
5818         return cnst;
5819 }
5820
5821 /**
5822  * Parse a character constant.
5823  */
5824 static expression_t *parse_character_constant(void)
5825 {
5826         expression_t *cnst = allocate_expression_zero(EXPR_CHARACTER_CONSTANT);
5827
5828         cnst->base.source_position = *HERE;
5829         cnst->base.type            = token.datatype;
5830         cnst->conste.v.character   = token.v.string;
5831
5832         if (cnst->conste.v.character.size != 1) {
5833                 if (warning.multichar && (c_mode & _GNUC)) {
5834                         /* TODO */
5835                         warningf(HERE, "multi-character character constant");
5836                 } else {
5837                         errorf(HERE, "more than 1 characters in character constant");
5838                 }
5839         }
5840         next_token();
5841
5842         return cnst;
5843 }
5844
5845 /**
5846  * Parse a wide character constant.
5847  */
5848 static expression_t *parse_wide_character_constant(void)
5849 {
5850         expression_t *cnst = allocate_expression_zero(EXPR_WIDE_CHARACTER_CONSTANT);
5851
5852         cnst->base.source_position    = *HERE;
5853         cnst->base.type               = token.datatype;
5854         cnst->conste.v.wide_character = token.v.wide_string;
5855
5856         if (cnst->conste.v.wide_character.size != 1) {
5857                 if (warning.multichar && (c_mode & _GNUC)) {
5858                         /* TODO */
5859                         warningf(HERE, "multi-character character constant");
5860                 } else {
5861                         errorf(HERE, "more than 1 characters in character constant");
5862                 }
5863         }
5864         next_token();
5865
5866         return cnst;
5867 }
5868
5869 /**
5870  * Parse a float constant.
5871  */
5872 static expression_t *parse_float_const(void)
5873 {
5874         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
5875         cnst->base.type            = token.datatype;
5876         cnst->conste.v.float_value = token.v.floatvalue;
5877
5878         next_token();
5879
5880         return cnst;
5881 }
5882
5883 static declaration_t *create_implicit_function(symbol_t *symbol,
5884                 const source_position_t *source_position)
5885 {
5886         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION, source_position);
5887         ntype->function.return_type            = type_int;
5888         ntype->function.unspecified_parameters = true;
5889
5890         type_t *type = typehash_insert(ntype);
5891         if (type != ntype) {
5892                 free_type(ntype);
5893         }
5894
5895         declaration_t *const declaration    = allocate_declaration_zero();
5896         declaration->storage_class          = STORAGE_CLASS_EXTERN;
5897         declaration->declared_storage_class = STORAGE_CLASS_EXTERN;
5898         declaration->type                   = type;
5899         declaration->symbol                 = symbol;
5900         declaration->source_position        = *source_position;
5901         declaration->implicit               = true;
5902
5903         bool strict_prototypes_old = warning.strict_prototypes;
5904         warning.strict_prototypes  = false;
5905         record_declaration(declaration, false);
5906         warning.strict_prototypes = strict_prototypes_old;
5907
5908         return declaration;
5909 }
5910
5911 /**
5912  * Creates a return_type (func)(argument_type) function type if not
5913  * already exists.
5914  */
5915 static type_t *make_function_2_type(type_t *return_type, type_t *argument_type1,
5916                                     type_t *argument_type2)
5917 {
5918         function_parameter_t *parameter2
5919                 = obstack_alloc(type_obst, sizeof(parameter2[0]));
5920         memset(parameter2, 0, sizeof(parameter2[0]));
5921         parameter2->type = argument_type2;
5922
5923         function_parameter_t *parameter1
5924                 = obstack_alloc(type_obst, sizeof(parameter1[0]));
5925         memset(parameter1, 0, sizeof(parameter1[0]));
5926         parameter1->type = argument_type1;
5927         parameter1->next = parameter2;
5928
5929         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5930         type->function.return_type = return_type;
5931         type->function.parameters  = parameter1;
5932
5933         type_t *result = typehash_insert(type);
5934         if (result != type) {
5935                 free_type(type);
5936         }
5937
5938         return result;
5939 }
5940
5941 /**
5942  * Creates a return_type (func)(argument_type) function type if not
5943  * already exists.
5944  *
5945  * @param return_type    the return type
5946  * @param argument_type  the argument type
5947  */
5948 static type_t *make_function_1_type(type_t *return_type, type_t *argument_type)
5949 {
5950         function_parameter_t *parameter
5951                 = obstack_alloc(type_obst, sizeof(parameter[0]));
5952         memset(parameter, 0, sizeof(parameter[0]));
5953         parameter->type = argument_type;
5954
5955         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5956         type->function.return_type = return_type;
5957         type->function.parameters  = parameter;
5958
5959         type_t *result = typehash_insert(type);
5960         if (result != type) {
5961                 free_type(type);
5962         }
5963
5964         return result;
5965 }
5966
5967 static type_t *make_function_0_type(type_t *return_type)
5968 {
5969         type_t *type               = allocate_type_zero(TYPE_FUNCTION, &builtin_source_position);
5970         type->function.return_type = return_type;
5971         type->function.parameters  = NULL;
5972
5973         type_t *result = typehash_insert(type);
5974         if (result != type) {
5975                 free_type(type);
5976         }
5977
5978         return result;
5979 }
5980
5981 /**
5982  * Creates a function type for some function like builtins.
5983  *
5984  * @param symbol   the symbol describing the builtin
5985  */
5986 static type_t *get_builtin_symbol_type(symbol_t *symbol)
5987 {
5988         switch(symbol->ID) {
5989         case T___builtin_alloca:
5990                 return make_function_1_type(type_void_ptr, type_size_t);
5991         case T___builtin_huge_val:
5992                 return make_function_0_type(type_double);
5993         case T___builtin_nan:
5994                 return make_function_1_type(type_double, type_char_ptr);
5995         case T___builtin_nanf:
5996                 return make_function_1_type(type_float, type_char_ptr);
5997         case T___builtin_nand:
5998                 return make_function_1_type(type_long_double, type_char_ptr);
5999         case T___builtin_va_end:
6000                 return make_function_1_type(type_void, type_valist);
6001         case T___builtin_expect:
6002                 return make_function_2_type(type_long, type_long, type_long);
6003         default:
6004                 internal_errorf(HERE, "not implemented builtin symbol found");
6005         }
6006 }
6007
6008 /**
6009  * Performs automatic type cast as described in § 6.3.2.1.
6010  *
6011  * @param orig_type  the original type
6012  */
6013 static type_t *automatic_type_conversion(type_t *orig_type)
6014 {
6015         type_t *type = skip_typeref(orig_type);
6016         if (is_type_array(type)) {
6017                 array_type_t *array_type   = &type->array;
6018                 type_t       *element_type = array_type->element_type;
6019                 unsigned      qualifiers   = array_type->base.qualifiers;
6020
6021                 return make_pointer_type(element_type, qualifiers);
6022         }
6023
6024         if (is_type_function(type)) {
6025                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6026         }
6027
6028         return orig_type;
6029 }
6030
6031 /**
6032  * reverts the automatic casts of array to pointer types and function
6033  * to function-pointer types as defined § 6.3.2.1
6034  */
6035 type_t *revert_automatic_type_conversion(const expression_t *expression)
6036 {
6037         switch (expression->kind) {
6038                 case EXPR_REFERENCE: return expression->reference.declaration->type;
6039
6040                 case EXPR_SELECT:
6041                         return get_qualified_type(expression->select.compound_entry->type,
6042                                                   expression->base.type->base.qualifiers);
6043
6044                 case EXPR_UNARY_DEREFERENCE: {
6045                         const expression_t *const value = expression->unary.value;
6046                         type_t             *const type  = skip_typeref(value->base.type);
6047                         assert(is_type_pointer(type));
6048                         return type->pointer.points_to;
6049                 }
6050
6051                 case EXPR_BUILTIN_SYMBOL:
6052                         return get_builtin_symbol_type(expression->builtin_symbol.symbol);
6053
6054                 case EXPR_ARRAY_ACCESS: {
6055                         const expression_t *array_ref = expression->array_access.array_ref;
6056                         type_t             *type_left = skip_typeref(array_ref->base.type);
6057                         if (!is_type_valid(type_left))
6058                                 return type_left;
6059                         assert(is_type_pointer(type_left));
6060                         return type_left->pointer.points_to;
6061                 }
6062
6063                 case EXPR_STRING_LITERAL: {
6064                         size_t size = expression->string.value.size;
6065                         return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6066                 }
6067
6068                 case EXPR_WIDE_STRING_LITERAL: {
6069                         size_t size = expression->wide_string.value.size;
6070                         return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6071                 }
6072
6073                 case EXPR_COMPOUND_LITERAL:
6074                         return expression->compound_literal.type;
6075
6076                 default: break;
6077         }
6078
6079         return expression->base.type;
6080 }
6081
6082 static expression_t *parse_reference(void)
6083 {
6084         expression_t *expression = allocate_expression_zero(EXPR_REFERENCE);
6085
6086         reference_expression_t *ref = &expression->reference;
6087         symbol_t *const symbol = token.v.symbol;
6088
6089         declaration_t *declaration = get_declaration(symbol, NAMESPACE_NORMAL);
6090
6091         if (declaration == NULL) {
6092                 if (!strict_mode && look_ahead(1)->type == '(') {
6093                         /* an implicitly declared function */
6094                         if (warning.implicit_function_declaration) {
6095                                 warningf(HERE, "implicit declaration of function '%Y'",
6096                                         symbol);
6097                         }
6098
6099                         declaration = create_implicit_function(symbol, HERE);
6100                 } else {
6101                         errorf(HERE, "unknown symbol '%Y' found.", symbol);
6102                         declaration = create_error_declaration(symbol, STORAGE_CLASS_NONE);
6103                 }
6104         }
6105
6106         type_t *type = declaration->type;
6107
6108         /* we always do the auto-type conversions; the & and sizeof parser contains
6109          * code to revert this! */
6110         type = automatic_type_conversion(type);
6111
6112         ref->declaration = declaration;
6113         ref->base.type   = type;
6114
6115         /* this declaration is used */
6116         declaration->used = true;
6117
6118         /* check for deprecated functions */
6119         if (warning.deprecated_declarations &&
6120             declaration->modifiers & DM_DEPRECATED) {
6121                 char const *const prefix = is_type_function(declaration->type) ?
6122                         "function" : "variable";
6123
6124                 if (declaration->deprecated_string != NULL) {
6125                         warningf(HERE, "%s '%Y' is deprecated (declared %P): \"%s\"",
6126                                 prefix, declaration->symbol, &declaration->source_position,
6127                                 declaration->deprecated_string);
6128                 } else {
6129                         warningf(HERE, "%s '%Y' is deprecated (declared %P)", prefix,
6130                                 declaration->symbol, &declaration->source_position);
6131                 }
6132         }
6133         if (warning.init_self && declaration == current_init_decl) {
6134                 current_init_decl = NULL;
6135                 warningf(HERE, "variable '%#T' is initialized by itself",
6136                         declaration->type, declaration->symbol);
6137         }
6138
6139         next_token();
6140         return expression;
6141 }
6142
6143 static bool semantic_cast(expression_t *cast)
6144 {
6145         expression_t            *expression      = cast->unary.value;
6146         type_t                  *orig_dest_type  = cast->base.type;
6147         type_t                  *orig_type_right = expression->base.type;
6148         type_t            const *dst_type        = skip_typeref(orig_dest_type);
6149         type_t            const *src_type        = skip_typeref(orig_type_right);
6150         source_position_t const *pos             = &cast->base.source_position;
6151
6152         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
6153         if (dst_type == type_void)
6154                 return true;
6155
6156         /* only integer and pointer can be casted to pointer */
6157         if (is_type_pointer(dst_type)  &&
6158             !is_type_pointer(src_type) &&
6159             !is_type_integer(src_type) &&
6160             is_type_valid(src_type)) {
6161                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
6162                 return false;
6163         }
6164
6165         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
6166                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
6167                 return false;
6168         }
6169
6170         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
6171                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
6172                 return false;
6173         }
6174
6175         if (warning.cast_qual &&
6176             is_type_pointer(src_type) &&
6177             is_type_pointer(dst_type)) {
6178                 type_t *src = skip_typeref(src_type->pointer.points_to);
6179                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
6180                 unsigned missing_qualifiers =
6181                         src->base.qualifiers & ~dst->base.qualifiers;
6182                 if (missing_qualifiers != 0) {
6183                         warningf(pos,
6184                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
6185                                  missing_qualifiers, orig_type_right);
6186                 }
6187         }
6188         return true;
6189 }
6190
6191 static expression_t *parse_compound_literal(type_t *type)
6192 {
6193         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
6194
6195         parse_initializer_env_t env;
6196         env.type             = type;
6197         env.declaration      = NULL;
6198         env.must_be_constant = false;
6199         initializer_t *initializer = parse_initializer(&env);
6200         type = env.type;
6201
6202         expression->compound_literal.initializer = initializer;
6203         expression->compound_literal.type        = type;
6204         expression->base.type                    = automatic_type_conversion(type);
6205
6206         return expression;
6207 }
6208
6209 /**
6210  * Parse a cast expression.
6211  */
6212 static expression_t *parse_cast(void)
6213 {
6214         add_anchor_token(')');
6215
6216         source_position_t source_position = token.source_position;
6217
6218         type_t *type  = parse_typename();
6219
6220         rem_anchor_token(')');
6221         expect(')');
6222
6223         if (token.type == '{') {
6224                 return parse_compound_literal(type);
6225         }
6226
6227         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
6228         cast->base.source_position = source_position;
6229
6230         expression_t *value = parse_sub_expression(20);
6231         cast->base.type   = type;
6232         cast->unary.value = value;
6233
6234         if (! semantic_cast(cast)) {
6235                 /* TODO: record the error in the AST. else it is impossible to detect it */
6236         }
6237
6238         return cast;
6239 end_error:
6240         return create_invalid_expression();
6241 }
6242
6243 /**
6244  * Parse a statement expression.
6245  */
6246 static expression_t *parse_statement_expression(void)
6247 {
6248         add_anchor_token(')');
6249
6250         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
6251
6252         statement_t *statement           = parse_compound_statement(true);
6253         expression->statement.statement  = statement;
6254         expression->base.source_position = statement->base.source_position;
6255
6256         /* find last statement and use its type */
6257         type_t *type = type_void;
6258         const statement_t *stmt = statement->compound.statements;
6259         if (stmt != NULL) {
6260                 while (stmt->base.next != NULL)
6261                         stmt = stmt->base.next;
6262
6263                 if (stmt->kind == STATEMENT_EXPRESSION) {
6264                         type = stmt->expression.expression->base.type;
6265                 }
6266         } else {
6267                 warningf(&expression->base.source_position, "empty statement expression ({})");
6268         }
6269         expression->base.type = type;
6270
6271         rem_anchor_token(')');
6272         expect(')');
6273
6274 end_error:
6275         return expression;
6276 }
6277
6278 /**
6279  * Parse a parenthesized expression.
6280  */
6281 static expression_t *parse_parenthesized_expression(void)
6282 {
6283         eat('(');
6284
6285         switch(token.type) {
6286         case '{':
6287                 /* gcc extension: a statement expression */
6288                 return parse_statement_expression();
6289
6290         TYPE_QUALIFIERS
6291         TYPE_SPECIFIERS
6292                 return parse_cast();
6293         case T_IDENTIFIER:
6294                 if (is_typedef_symbol(token.v.symbol)) {
6295                         return parse_cast();
6296                 }
6297         }
6298
6299         add_anchor_token(')');
6300         expression_t *result = parse_expression();
6301         rem_anchor_token(')');
6302         expect(')');
6303
6304 end_error:
6305         return result;
6306 }
6307
6308 static expression_t *parse_function_keyword(void)
6309 {
6310         next_token();
6311         /* TODO */
6312
6313         if (current_function == NULL) {
6314                 errorf(HERE, "'__func__' used outside of a function");
6315         }
6316
6317         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6318         expression->base.type     = type_char_ptr;
6319         expression->funcname.kind = FUNCNAME_FUNCTION;
6320
6321         return expression;
6322 }
6323
6324 static expression_t *parse_pretty_function_keyword(void)
6325 {
6326         eat(T___PRETTY_FUNCTION__);
6327
6328         if (current_function == NULL) {
6329                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
6330         }
6331
6332         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6333         expression->base.type     = type_char_ptr;
6334         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
6335
6336         return expression;
6337 }
6338
6339 static expression_t *parse_funcsig_keyword(void)
6340 {
6341         eat(T___FUNCSIG__);
6342
6343         if (current_function == NULL) {
6344                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
6345         }
6346
6347         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6348         expression->base.type     = type_char_ptr;
6349         expression->funcname.kind = FUNCNAME_FUNCSIG;
6350
6351         return expression;
6352 }
6353
6354 static expression_t *parse_funcdname_keyword(void)
6355 {
6356         eat(T___FUNCDNAME__);
6357
6358         if (current_function == NULL) {
6359                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6360         }
6361
6362         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6363         expression->base.type     = type_char_ptr;
6364         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6365
6366         return expression;
6367 }
6368
6369 static designator_t *parse_designator(void)
6370 {
6371         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6372         result->source_position = *HERE;
6373
6374         if (token.type != T_IDENTIFIER) {
6375                 parse_error_expected("while parsing member designator",
6376                                      T_IDENTIFIER, NULL);
6377                 return NULL;
6378         }
6379         result->symbol = token.v.symbol;
6380         next_token();
6381
6382         designator_t *last_designator = result;
6383         while(true) {
6384                 if (token.type == '.') {
6385                         next_token();
6386                         if (token.type != T_IDENTIFIER) {
6387                                 parse_error_expected("while parsing member designator",
6388                                                      T_IDENTIFIER, NULL);
6389                                 return NULL;
6390                         }
6391                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6392                         designator->source_position = *HERE;
6393                         designator->symbol          = token.v.symbol;
6394                         next_token();
6395
6396                         last_designator->next = designator;
6397                         last_designator       = designator;
6398                         continue;
6399                 }
6400                 if (token.type == '[') {
6401                         next_token();
6402                         add_anchor_token(']');
6403                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6404                         designator->source_position = *HERE;
6405                         designator->array_index     = parse_expression();
6406                         rem_anchor_token(']');
6407                         expect(']');
6408                         if (designator->array_index == NULL) {
6409                                 return NULL;
6410                         }
6411
6412                         last_designator->next = designator;
6413                         last_designator       = designator;
6414                         continue;
6415                 }
6416                 break;
6417         }
6418
6419         return result;
6420 end_error:
6421         return NULL;
6422 }
6423
6424 /**
6425  * Parse the __builtin_offsetof() expression.
6426  */
6427 static expression_t *parse_offsetof(void)
6428 {
6429         eat(T___builtin_offsetof);
6430
6431         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6432         expression->base.type    = type_size_t;
6433
6434         expect('(');
6435         add_anchor_token(',');
6436         type_t *type = parse_typename();
6437         rem_anchor_token(',');
6438         expect(',');
6439         add_anchor_token(')');
6440         designator_t *designator = parse_designator();
6441         rem_anchor_token(')');
6442         expect(')');
6443
6444         expression->offsetofe.type       = type;
6445         expression->offsetofe.designator = designator;
6446
6447         type_path_t path;
6448         memset(&path, 0, sizeof(path));
6449         path.top_type = type;
6450         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6451
6452         descend_into_subtype(&path);
6453
6454         if (!walk_designator(&path, designator, true)) {
6455                 return create_invalid_expression();
6456         }
6457
6458         DEL_ARR_F(path.path);
6459
6460         return expression;
6461 end_error:
6462         return create_invalid_expression();
6463 }
6464
6465 /**
6466  * Parses a _builtin_va_start() expression.
6467  */
6468 static expression_t *parse_va_start(void)
6469 {
6470         eat(T___builtin_va_start);
6471
6472         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6473
6474         expect('(');
6475         add_anchor_token(',');
6476         expression->va_starte.ap = parse_assignment_expression();
6477         rem_anchor_token(',');
6478         expect(',');
6479         expression_t *const expr = parse_assignment_expression();
6480         if (expr->kind == EXPR_REFERENCE) {
6481                 declaration_t *const decl = expr->reference.declaration;
6482                 if (decl->parent_scope != &current_function->scope || decl->next != NULL) {
6483                         errorf(&expr->base.source_position,
6484                                "second argument of 'va_start' must be last parameter of the current function");
6485                 }
6486                 expression->va_starte.parameter = decl;
6487                 expect(')');
6488                 return expression;
6489         }
6490         expect(')');
6491 end_error:
6492         return create_invalid_expression();
6493 }
6494
6495 /**
6496  * Parses a _builtin_va_arg() expression.
6497  */
6498 static expression_t *parse_va_arg(void)
6499 {
6500         eat(T___builtin_va_arg);
6501
6502         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6503
6504         expect('(');
6505         expression->va_arge.ap = parse_assignment_expression();
6506         expect(',');
6507         expression->base.type = parse_typename();
6508         expect(')');
6509
6510         return expression;
6511 end_error:
6512         return create_invalid_expression();
6513 }
6514
6515 static expression_t *parse_builtin_symbol(void)
6516 {
6517         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_SYMBOL);
6518
6519         symbol_t *symbol = token.v.symbol;
6520
6521         expression->builtin_symbol.symbol = symbol;
6522         next_token();
6523
6524         type_t *type = get_builtin_symbol_type(symbol);
6525         type = automatic_type_conversion(type);
6526
6527         expression->base.type = type;
6528         return expression;
6529 }
6530
6531 /**
6532  * Parses a __builtin_constant() expression.
6533  */
6534 static expression_t *parse_builtin_constant(void)
6535 {
6536         eat(T___builtin_constant_p);
6537
6538         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6539
6540         expect('(');
6541         add_anchor_token(')');
6542         expression->builtin_constant.value = parse_assignment_expression();
6543         rem_anchor_token(')');
6544         expect(')');
6545         expression->base.type = type_int;
6546
6547         return expression;
6548 end_error:
6549         return create_invalid_expression();
6550 }
6551
6552 /**
6553  * Parses a __builtin_prefetch() expression.
6554  */
6555 static expression_t *parse_builtin_prefetch(void)
6556 {
6557         eat(T___builtin_prefetch);
6558
6559         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_PREFETCH);
6560
6561         expect('(');
6562         add_anchor_token(')');
6563         expression->builtin_prefetch.adr = parse_assignment_expression();
6564         if (token.type == ',') {
6565                 next_token();
6566                 expression->builtin_prefetch.rw = parse_assignment_expression();
6567         }
6568         if (token.type == ',') {
6569                 next_token();
6570                 expression->builtin_prefetch.locality = parse_assignment_expression();
6571         }
6572         rem_anchor_token(')');
6573         expect(')');
6574         expression->base.type = type_void;
6575
6576         return expression;
6577 end_error:
6578         return create_invalid_expression();
6579 }
6580
6581 /**
6582  * Parses a __builtin_is_*() compare expression.
6583  */
6584 static expression_t *parse_compare_builtin(void)
6585 {
6586         expression_t *expression;
6587
6588         switch(token.type) {
6589         case T___builtin_isgreater:
6590                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6591                 break;
6592         case T___builtin_isgreaterequal:
6593                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6594                 break;
6595         case T___builtin_isless:
6596                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6597                 break;
6598         case T___builtin_islessequal:
6599                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6600                 break;
6601         case T___builtin_islessgreater:
6602                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6603                 break;
6604         case T___builtin_isunordered:
6605                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6606                 break;
6607         default:
6608                 internal_errorf(HERE, "invalid compare builtin found");
6609                 break;
6610         }
6611         expression->base.source_position = *HERE;
6612         next_token();
6613
6614         expect('(');
6615         expression->binary.left = parse_assignment_expression();
6616         expect(',');
6617         expression->binary.right = parse_assignment_expression();
6618         expect(')');
6619
6620         type_t *const orig_type_left  = expression->binary.left->base.type;
6621         type_t *const orig_type_right = expression->binary.right->base.type;
6622
6623         type_t *const type_left  = skip_typeref(orig_type_left);
6624         type_t *const type_right = skip_typeref(orig_type_right);
6625         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6626                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6627                         type_error_incompatible("invalid operands in comparison",
6628                                 &expression->base.source_position, orig_type_left, orig_type_right);
6629                 }
6630         } else {
6631                 semantic_comparison(&expression->binary);
6632         }
6633
6634         return expression;
6635 end_error:
6636         return create_invalid_expression();
6637 }
6638
6639 #if 0
6640 /**
6641  * Parses a __builtin_expect() expression.
6642  */
6643 static expression_t *parse_builtin_expect(void)
6644 {
6645         eat(T___builtin_expect);
6646
6647         expression_t *expression
6648                 = allocate_expression_zero(EXPR_BINARY_BUILTIN_EXPECT);
6649
6650         expect('(');
6651         expression->binary.left = parse_assignment_expression();
6652         expect(',');
6653         expression->binary.right = parse_constant_expression();
6654         expect(')');
6655
6656         expression->base.type = expression->binary.left->base.type;
6657
6658         return expression;
6659 end_error:
6660         return create_invalid_expression();
6661 }
6662 #endif
6663
6664 /**
6665  * Parses a MS assume() expression.
6666  */
6667 static expression_t *parse_assume(void)
6668 {
6669         eat(T__assume);
6670
6671         expression_t *expression
6672                 = allocate_expression_zero(EXPR_UNARY_ASSUME);
6673
6674         expect('(');
6675         add_anchor_token(')');
6676         expression->unary.value = parse_assignment_expression();
6677         rem_anchor_token(')');
6678         expect(')');
6679
6680         expression->base.type = type_void;
6681         return expression;
6682 end_error:
6683         return create_invalid_expression();
6684 }
6685
6686 /**
6687  * Return the declaration for a given label symbol or create a new one.
6688  *
6689  * @param symbol  the symbol of the label
6690  */
6691 static declaration_t *get_label(symbol_t *symbol)
6692 {
6693         declaration_t *candidate;
6694         assert(current_function != NULL);
6695
6696         candidate = get_declaration(symbol, NAMESPACE_LOCAL_LABEL);
6697         /* if we found a local label, we already created the declaration */
6698         if (candidate != NULL) {
6699                 assert(candidate->parent_scope == scope);
6700                 return candidate;
6701         }
6702
6703         candidate = get_declaration(symbol, NAMESPACE_LABEL);
6704         /* if we found a label in the same function, then we already created the
6705          * declaration */
6706         if (candidate != NULL
6707                         && candidate->parent_scope == &current_function->scope) {
6708                 return candidate;
6709         }
6710
6711         /* otherwise we need to create a new one */
6712         declaration_t *const declaration = allocate_declaration_zero();
6713         declaration->namespc       = NAMESPACE_LABEL;
6714         declaration->symbol        = symbol;
6715
6716         label_push(declaration);
6717
6718         return declaration;
6719 }
6720
6721 /**
6722  * Parses a GNU && label address expression.
6723  */
6724 static expression_t *parse_label_address(void)
6725 {
6726         source_position_t source_position = token.source_position;
6727         eat(T_ANDAND);
6728         if (token.type != T_IDENTIFIER) {
6729                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
6730                 goto end_error;
6731         }
6732         symbol_t *symbol = token.v.symbol;
6733         next_token();
6734
6735         declaration_t *label = get_label(symbol);
6736
6737         label->used          = true;
6738         label->address_taken = true;
6739
6740         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
6741         expression->base.source_position = source_position;
6742
6743         /* label address is threaten as a void pointer */
6744         expression->base.type                 = type_void_ptr;
6745         expression->label_address.declaration = label;
6746         return expression;
6747 end_error:
6748         return create_invalid_expression();
6749 }
6750
6751 /**
6752  * Parse a microsoft __noop expression.
6753  */
6754 static expression_t *parse_noop_expression(void)
6755 {
6756         source_position_t source_position = *HERE;
6757         eat(T___noop);
6758
6759         if (token.type == '(') {
6760                 /* parse arguments */
6761                 eat('(');
6762                 add_anchor_token(')');
6763                 add_anchor_token(',');
6764
6765                 if (token.type != ')') {
6766                         while(true) {
6767                                 (void)parse_assignment_expression();
6768                                 if (token.type != ',')
6769                                         break;
6770                                 next_token();
6771                         }
6772                 }
6773         }
6774         rem_anchor_token(',');
6775         rem_anchor_token(')');
6776         expect(')');
6777
6778         /* the result is a (int)0 */
6779         expression_t *cnst         = allocate_expression_zero(EXPR_CONST);
6780         cnst->base.source_position = source_position;
6781         cnst->base.type            = type_int;
6782         cnst->conste.v.int_value   = 0;
6783         cnst->conste.is_ms_noop    = true;
6784
6785         return cnst;
6786
6787 end_error:
6788         return create_invalid_expression();
6789 }
6790
6791 /**
6792  * Parses a primary expression.
6793  */
6794 static expression_t *parse_primary_expression(void)
6795 {
6796         switch (token.type) {
6797                 case T_INTEGER:                  return parse_int_const();
6798                 case T_CHARACTER_CONSTANT:       return parse_character_constant();
6799                 case T_WIDE_CHARACTER_CONSTANT:  return parse_wide_character_constant();
6800                 case T_FLOATINGPOINT:            return parse_float_const();
6801                 case T_STRING_LITERAL:
6802                 case T_WIDE_STRING_LITERAL:      return parse_string_const();
6803                 case T_IDENTIFIER:               return parse_reference();
6804                 case T___FUNCTION__:
6805                 case T___func__:                 return parse_function_keyword();
6806                 case T___PRETTY_FUNCTION__:      return parse_pretty_function_keyword();
6807                 case T___FUNCSIG__:              return parse_funcsig_keyword();
6808                 case T___FUNCDNAME__:            return parse_funcdname_keyword();
6809                 case T___builtin_offsetof:       return parse_offsetof();
6810                 case T___builtin_va_start:       return parse_va_start();
6811                 case T___builtin_va_arg:         return parse_va_arg();
6812                 case T___builtin_expect:
6813                 case T___builtin_alloca:
6814                 case T___builtin_nan:
6815                 case T___builtin_nand:
6816                 case T___builtin_nanf:
6817                 case T___builtin_huge_val:
6818                 case T___builtin_va_end:         return parse_builtin_symbol();
6819                 case T___builtin_isgreater:
6820                 case T___builtin_isgreaterequal:
6821                 case T___builtin_isless:
6822                 case T___builtin_islessequal:
6823                 case T___builtin_islessgreater:
6824                 case T___builtin_isunordered:    return parse_compare_builtin();
6825                 case T___builtin_constant_p:     return parse_builtin_constant();
6826                 case T___builtin_prefetch:       return parse_builtin_prefetch();
6827                 case T__assume:                  return parse_assume();
6828                 case T_ANDAND:
6829                         if (c_mode & _GNUC)
6830                                 return parse_label_address();
6831                         break;
6832
6833                 case '(':                        return parse_parenthesized_expression();
6834                 case T___noop:                   return parse_noop_expression();
6835         }
6836
6837         errorf(HERE, "unexpected token %K, expected an expression", &token);
6838         return create_invalid_expression();
6839 }
6840
6841 /**
6842  * Check if the expression has the character type and issue a warning then.
6843  */
6844 static void check_for_char_index_type(const expression_t *expression)
6845 {
6846         type_t       *const type      = expression->base.type;
6847         const type_t *const base_type = skip_typeref(type);
6848
6849         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
6850                         warning.char_subscripts) {
6851                 warningf(&expression->base.source_position,
6852                          "array subscript has type '%T'", type);
6853         }
6854 }
6855
6856 static expression_t *parse_array_expression(unsigned precedence,
6857                                             expression_t *left)
6858 {
6859         (void) precedence;
6860
6861         eat('[');
6862         add_anchor_token(']');
6863
6864         expression_t *inside = parse_expression();
6865
6866         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
6867
6868         array_access_expression_t *array_access = &expression->array_access;
6869
6870         type_t *const orig_type_left   = left->base.type;
6871         type_t *const orig_type_inside = inside->base.type;
6872
6873         type_t *const type_left   = skip_typeref(orig_type_left);
6874         type_t *const type_inside = skip_typeref(orig_type_inside);
6875
6876         type_t *return_type;
6877         if (is_type_pointer(type_left)) {
6878                 return_type             = type_left->pointer.points_to;
6879                 array_access->array_ref = left;
6880                 array_access->index     = inside;
6881                 check_for_char_index_type(inside);
6882         } else if (is_type_pointer(type_inside)) {
6883                 return_type             = type_inside->pointer.points_to;
6884                 array_access->array_ref = inside;
6885                 array_access->index     = left;
6886                 array_access->flipped   = true;
6887                 check_for_char_index_type(left);
6888         } else {
6889                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
6890                         errorf(HERE,
6891                                 "array access on object with non-pointer types '%T', '%T'",
6892                                 orig_type_left, orig_type_inside);
6893                 }
6894                 return_type             = type_error_type;
6895                 array_access->array_ref = left;
6896                 array_access->index     = inside;
6897         }
6898
6899         expression->base.type = automatic_type_conversion(return_type);
6900
6901         rem_anchor_token(']');
6902         if (token.type == ']') {
6903                 next_token();
6904         } else {
6905                 parse_error_expected("Problem while parsing array access", ']', NULL);
6906         }
6907         return expression;
6908 }
6909
6910 static expression_t *parse_typeprop(expression_kind_t const kind,
6911                                     source_position_t const pos,
6912                                     unsigned const precedence)
6913 {
6914         expression_t *tp_expression = allocate_expression_zero(kind);
6915         tp_expression->base.type            = type_size_t;
6916         tp_expression->base.source_position = pos;
6917
6918         char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
6919
6920         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
6921                 next_token();
6922                 add_anchor_token(')');
6923                 type_t* const orig_type = parse_typename();
6924                 tp_expression->typeprop.type = orig_type;
6925
6926                 type_t const* const type = skip_typeref(orig_type);
6927                 char const* const wrong_type =
6928                         is_type_incomplete(type)    ? "incomplete"          :
6929                         type->kind == TYPE_FUNCTION ? "function designator" :
6930                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6931                         NULL;
6932                 if (wrong_type != NULL) {
6933                         errorf(&pos, "operand of %s expression must not be %s type '%T'",
6934                                what, wrong_type, type);
6935                 }
6936
6937                 rem_anchor_token(')');
6938                 expect(')');
6939         } else {
6940                 expression_t *expression = parse_sub_expression(precedence);
6941
6942                 type_t* const orig_type = revert_automatic_type_conversion(expression);
6943                 expression->base.type = orig_type;
6944
6945                 type_t const* const type = skip_typeref(orig_type);
6946                 char const* const wrong_type =
6947                         is_type_incomplete(type)    ? "incomplete"          :
6948                         type->kind == TYPE_FUNCTION ? "function designator" :
6949                         type->kind == TYPE_BITFIELD ? "bitfield"            :
6950                         NULL;
6951                 if (wrong_type != NULL) {
6952                         errorf(&pos, "operand of %s expression must not be expression of %s type '%T'", what, wrong_type, type);
6953                 }
6954
6955                 tp_expression->typeprop.type          = expression->base.type;
6956                 tp_expression->typeprop.tp_expression = expression;
6957         }
6958
6959 end_error:
6960         return tp_expression;
6961 }
6962
6963 static expression_t *parse_sizeof(unsigned precedence)
6964 {
6965         source_position_t pos = *HERE;
6966         eat(T_sizeof);
6967         return parse_typeprop(EXPR_SIZEOF, pos, precedence);
6968 }
6969
6970 static expression_t *parse_alignof(unsigned precedence)
6971 {
6972         source_position_t pos = *HERE;
6973         eat(T___alignof__);
6974         return parse_typeprop(EXPR_ALIGNOF, pos, precedence);
6975 }
6976
6977 static expression_t *parse_select_expression(unsigned precedence,
6978                                              expression_t *compound)
6979 {
6980         (void) precedence;
6981         assert(token.type == '.' || token.type == T_MINUSGREATER);
6982
6983         bool is_pointer = (token.type == T_MINUSGREATER);
6984         next_token();
6985
6986         expression_t *select    = allocate_expression_zero(EXPR_SELECT);
6987         select->select.compound = compound;
6988
6989         if (token.type != T_IDENTIFIER) {
6990                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
6991                 return select;
6992         }
6993         symbol_t *symbol = token.v.symbol;
6994         next_token();
6995
6996         type_t *const orig_type = compound->base.type;
6997         type_t *const type      = skip_typeref(orig_type);
6998
6999         type_t *type_left;
7000         bool    saw_error = false;
7001         if (is_type_pointer(type)) {
7002                 if (!is_pointer) {
7003                         errorf(HERE,
7004                                "request for member '%Y' in something not a struct or union, but '%T'",
7005                                symbol, orig_type);
7006                         saw_error = true;
7007                 }
7008                 type_left = skip_typeref(type->pointer.points_to);
7009         } else {
7010                 if (is_pointer && is_type_valid(type)) {
7011                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7012                         saw_error = true;
7013                 }
7014                 type_left = type;
7015         }
7016
7017         declaration_t *entry;
7018         if (type_left->kind == TYPE_COMPOUND_STRUCT ||
7019             type_left->kind == TYPE_COMPOUND_UNION) {
7020                 declaration_t *const declaration = type_left->compound.declaration;
7021
7022                 if (!declaration->init.complete) {
7023                         errorf(HERE, "request for member '%Y' of incomplete type '%T'",
7024                                symbol, type_left);
7025                         goto create_error_entry;
7026                 }
7027
7028                 entry = find_compound_entry(declaration, symbol);
7029                 if (entry == NULL) {
7030                         errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
7031                         goto create_error_entry;
7032                 }
7033         } else {
7034                 if (is_type_valid(type_left) && !saw_error) {
7035                         errorf(HERE,
7036                                "request for member '%Y' in something not a struct or union, but '%T'",
7037                                symbol, type_left);
7038                 }
7039 create_error_entry:
7040                 entry         = allocate_declaration_zero();
7041                 entry->symbol = symbol;
7042         }
7043
7044         select->select.compound_entry = entry;
7045
7046         type_t *const res_type =
7047                 get_qualified_type(entry->type, type_left->base.qualifiers);
7048
7049         /* we always do the auto-type conversions; the & and sizeof parser contains
7050          * code to revert this! */
7051         select->base.type = automatic_type_conversion(res_type);
7052
7053         type_t *skipped = skip_typeref(res_type);
7054         if (skipped->kind == TYPE_BITFIELD) {
7055                 select->base.type = skipped->bitfield.base_type;
7056         }
7057
7058         return select;
7059 }
7060
7061 static void check_call_argument(const function_parameter_t *parameter,
7062                                 call_argument_t *argument, unsigned pos)
7063 {
7064         type_t         *expected_type      = parameter->type;
7065         type_t         *expected_type_skip = skip_typeref(expected_type);
7066         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7067         expression_t   *arg_expr           = argument->expression;
7068         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7069
7070         /* handle transparent union gnu extension */
7071         if (is_type_union(expected_type_skip)
7072                         && (expected_type_skip->base.modifiers
7073                                 & TYPE_MODIFIER_TRANSPARENT_UNION)) {
7074                 declaration_t  *union_decl = expected_type_skip->compound.declaration;
7075
7076                 declaration_t *declaration = union_decl->scope.declarations;
7077                 type_t        *best_type   = NULL;
7078                 for ( ; declaration != NULL; declaration = declaration->next) {
7079                         type_t *decl_type = declaration->type;
7080                         error = semantic_assign(decl_type, arg_expr);
7081                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7082                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
7083                                 continue;
7084
7085                         if (error == ASSIGN_SUCCESS) {
7086                                 best_type = decl_type;
7087                         } else if (best_type == NULL) {
7088                                 best_type = decl_type;
7089                         }
7090                 }
7091
7092                 if (best_type != NULL) {
7093                         expected_type = best_type;
7094                 }
7095         }
7096
7097         error                = semantic_assign(expected_type, arg_expr);
7098         argument->expression = create_implicit_cast(argument->expression,
7099                                                     expected_type);
7100
7101         if (error != ASSIGN_SUCCESS) {
7102                 /* report exact scope in error messages (like "in argument 3") */
7103                 char buf[64];
7104                 snprintf(buf, sizeof(buf), "call argument %u", pos);
7105                 report_assign_error(error, expected_type, arg_expr,     buf,
7106                                                         &arg_expr->base.source_position);
7107         } else if (warning.traditional || warning.conversion) {
7108                 type_t *const promoted_type = get_default_promoted_type(arg_type);
7109                 if (!types_compatible(expected_type_skip, promoted_type) &&
7110                     !types_compatible(expected_type_skip, type_void_ptr) &&
7111                     !types_compatible(type_void_ptr,      promoted_type)) {
7112                         /* Deliberately show the skipped types in this warning */
7113                         warningf(&arg_expr->base.source_position,
7114                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
7115                                 pos, expected_type_skip, promoted_type);
7116                 }
7117         }
7118 }
7119
7120 /**
7121  * Parse a call expression, ie. expression '( ... )'.
7122  *
7123  * @param expression  the function address
7124  */
7125 static expression_t *parse_call_expression(unsigned precedence,
7126                                            expression_t *expression)
7127 {
7128         (void) precedence;
7129         expression_t *result = allocate_expression_zero(EXPR_CALL);
7130         result->base.source_position = expression->base.source_position;
7131
7132         call_expression_t *call = &result->call;
7133         call->function          = expression;
7134
7135         type_t *const orig_type = expression->base.type;
7136         type_t *const type      = skip_typeref(orig_type);
7137
7138         function_type_t *function_type = NULL;
7139         if (is_type_pointer(type)) {
7140                 type_t *const to_type = skip_typeref(type->pointer.points_to);
7141
7142                 if (is_type_function(to_type)) {
7143                         function_type   = &to_type->function;
7144                         call->base.type = function_type->return_type;
7145                 }
7146         }
7147
7148         if (function_type == NULL && is_type_valid(type)) {
7149                 errorf(HERE, "called object '%E' (type '%T') is not a pointer to a function", expression, orig_type);
7150         }
7151
7152         /* parse arguments */
7153         eat('(');
7154         add_anchor_token(')');
7155         add_anchor_token(',');
7156
7157         if (token.type != ')') {
7158                 call_argument_t *last_argument = NULL;
7159
7160                 while (true) {
7161                         call_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
7162
7163                         argument->expression = parse_assignment_expression();
7164                         if (last_argument == NULL) {
7165                                 call->arguments = argument;
7166                         } else {
7167                                 last_argument->next = argument;
7168                         }
7169                         last_argument = argument;
7170
7171                         if (token.type != ',')
7172                                 break;
7173                         next_token();
7174                 }
7175         }
7176         rem_anchor_token(',');
7177         rem_anchor_token(')');
7178         expect(')');
7179
7180         if (function_type == NULL)
7181                 return result;
7182
7183         function_parameter_t *parameter = function_type->parameters;
7184         call_argument_t      *argument  = call->arguments;
7185         if (!function_type->unspecified_parameters) {
7186                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
7187                                 parameter = parameter->next, argument = argument->next) {
7188                         check_call_argument(parameter, argument, ++pos);
7189                 }
7190
7191                 if (parameter != NULL) {
7192                         errorf(HERE, "too few arguments to function '%E'", expression);
7193                 } else if (argument != NULL && !function_type->variadic) {
7194                         errorf(HERE, "too many arguments to function '%E'", expression);
7195                 }
7196         }
7197
7198         /* do default promotion */
7199         for( ; argument != NULL; argument = argument->next) {
7200                 type_t *type = argument->expression->base.type;
7201
7202                 type = get_default_promoted_type(type);
7203
7204                 argument->expression
7205                         = create_implicit_cast(argument->expression, type);
7206         }
7207
7208         check_format(&result->call);
7209
7210         if (warning.aggregate_return &&
7211             is_type_compound(skip_typeref(function_type->return_type))) {
7212                 warningf(&result->base.source_position,
7213                          "function call has aggregate value");
7214         }
7215
7216 end_error:
7217         return result;
7218 }
7219
7220 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
7221
7222 static bool same_compound_type(const type_t *type1, const type_t *type2)
7223 {
7224         return
7225                 is_type_compound(type1) &&
7226                 type1->kind == type2->kind &&
7227                 type1->compound.declaration == type2->compound.declaration;
7228 }
7229
7230 /**
7231  * Parse a conditional expression, ie. 'expression ? ... : ...'.
7232  *
7233  * @param expression  the conditional expression
7234  */
7235 static expression_t *parse_conditional_expression(unsigned precedence,
7236                                                   expression_t *expression)
7237 {
7238         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
7239
7240         conditional_expression_t *conditional = &result->conditional;
7241         conditional->base.source_position = *HERE;
7242         conditional->condition            = expression;
7243
7244         eat('?');
7245         add_anchor_token(':');
7246
7247         /* 6.5.15.2 */
7248         type_t *const condition_type_orig = expression->base.type;
7249         type_t *const condition_type      = skip_typeref(condition_type_orig);
7250         if (!is_type_scalar(condition_type) && is_type_valid(condition_type)) {
7251                 type_error("expected a scalar type in conditional condition",
7252                            &expression->base.source_position, condition_type_orig);
7253         }
7254
7255         expression_t *true_expression = expression;
7256         bool          gnu_cond = false;
7257         if ((c_mode & _GNUC) && token.type == ':') {
7258                 gnu_cond = true;
7259         } else
7260                 true_expression = parse_expression();
7261         rem_anchor_token(':');
7262         expect(':');
7263         expression_t *false_expression = parse_sub_expression(precedence);
7264
7265         type_t *const orig_true_type  = true_expression->base.type;
7266         type_t *const orig_false_type = false_expression->base.type;
7267         type_t *const true_type       = skip_typeref(orig_true_type);
7268         type_t *const false_type      = skip_typeref(orig_false_type);
7269
7270         /* 6.5.15.3 */
7271         type_t *result_type;
7272         if (is_type_atomic(true_type, ATOMIC_TYPE_VOID) ||
7273                 is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7274                 if (!is_type_atomic(true_type, ATOMIC_TYPE_VOID)
7275                     || !is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7276                         warningf(&conditional->base.source_position,
7277                                         "ISO C forbids conditional expression with only one void side");
7278                 }
7279                 result_type = type_void;
7280         } else if (is_type_arithmetic(true_type)
7281                    && is_type_arithmetic(false_type)) {
7282                 result_type = semantic_arithmetic(true_type, false_type);
7283
7284                 true_expression  = create_implicit_cast(true_expression, result_type);
7285                 false_expression = create_implicit_cast(false_expression, result_type);
7286
7287                 conditional->true_expression  = true_expression;
7288                 conditional->false_expression = false_expression;
7289                 conditional->base.type        = result_type;
7290         } else if (same_compound_type(true_type, false_type)) {
7291                 /* just take 1 of the 2 types */
7292                 result_type = true_type;
7293         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
7294                 type_t *pointer_type;
7295                 type_t *other_type;
7296                 expression_t *other_expression;
7297                 if (is_type_pointer(true_type) &&
7298                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
7299                         pointer_type     = true_type;
7300                         other_type       = false_type;
7301                         other_expression = false_expression;
7302                 } else {
7303                         pointer_type     = false_type;
7304                         other_type       = true_type;
7305                         other_expression = true_expression;
7306                 }
7307
7308                 if (is_null_pointer_constant(other_expression)) {
7309                         result_type = pointer_type;
7310                 } else if (is_type_pointer(other_type)) {
7311                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
7312                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
7313
7314                         type_t *to;
7315                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
7316                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
7317                                 to = type_void;
7318                         } else if (types_compatible(get_unqualified_type(to1),
7319                                                     get_unqualified_type(to2))) {
7320                                 to = to1;
7321                         } else {
7322                                 warningf(&conditional->base.source_position,
7323                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
7324                                         true_type, false_type);
7325                                 to = type_void;
7326                         }
7327
7328                         type_t *const type =
7329                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
7330                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
7331                 } else if (is_type_integer(other_type)) {
7332                         warningf(&conditional->base.source_position,
7333                                         "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
7334                         result_type = pointer_type;
7335                 } else {
7336                         type_error_incompatible("while parsing conditional",
7337                                         &expression->base.source_position, true_type, false_type);
7338                         result_type = type_error_type;
7339                 }
7340         } else {
7341                 /* TODO: one pointer to void*, other some pointer */
7342
7343                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
7344                         type_error_incompatible("while parsing conditional",
7345                                                 &conditional->base.source_position, true_type,
7346                                                 false_type);
7347                 }
7348                 result_type = type_error_type;
7349         }
7350
7351         conditional->true_expression
7352                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
7353         conditional->false_expression
7354                 = create_implicit_cast(false_expression, result_type);
7355         conditional->base.type = result_type;
7356         return result;
7357 end_error:
7358         return create_invalid_expression();
7359 }
7360
7361 /**
7362  * Parse an extension expression.
7363  */
7364 static expression_t *parse_extension(unsigned precedence)
7365 {
7366         eat(T___extension__);
7367
7368         /* TODO enable extensions */
7369         expression_t *expression = parse_sub_expression(precedence);
7370         /* TODO disable extensions */
7371         return expression;
7372 }
7373
7374 /**
7375  * Parse a __builtin_classify_type() expression.
7376  */
7377 static expression_t *parse_builtin_classify_type(const unsigned precedence)
7378 {
7379         eat(T___builtin_classify_type);
7380
7381         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
7382         result->base.type    = type_int;
7383
7384         expect('(');
7385         add_anchor_token(')');
7386         expression_t *expression = parse_sub_expression(precedence);
7387         rem_anchor_token(')');
7388         expect(')');
7389         result->classify_type.type_expression = expression;
7390
7391         return result;
7392 end_error:
7393         return create_invalid_expression();
7394 }
7395
7396 static bool check_pointer_arithmetic(const source_position_t *source_position,
7397                                      type_t *pointer_type,
7398                                      type_t *orig_pointer_type)
7399 {
7400         type_t *points_to = pointer_type->pointer.points_to;
7401         points_to = skip_typeref(points_to);
7402
7403         if (is_type_incomplete(points_to)) {
7404                 if (!(c_mode & _GNUC) || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7405                         errorf(source_position,
7406                                "arithmetic with pointer to incomplete type '%T' not allowed",
7407                                orig_pointer_type);
7408                         return false;
7409                 } else if (warning.pointer_arith) {
7410                         warningf(source_position,
7411                                  "pointer of type '%T' used in arithmetic",
7412                                  orig_pointer_type);
7413                 }
7414         } else if (is_type_function(points_to)) {
7415                 if (!(c_mode && _GNUC)) {
7416                         errorf(source_position,
7417                                "arithmetic with pointer to function type '%T' not allowed",
7418                                orig_pointer_type);
7419                         return false;
7420                 } else if (warning.pointer_arith) {
7421                         warningf(source_position,
7422                                  "pointer to a function '%T' used in arithmetic",
7423                                  orig_pointer_type);
7424                 }
7425         }
7426         return true;
7427 }
7428
7429 static bool is_lvalue(const expression_t *expression)
7430 {
7431         switch (expression->kind) {
7432         case EXPR_REFERENCE:
7433         case EXPR_ARRAY_ACCESS:
7434         case EXPR_SELECT:
7435         case EXPR_UNARY_DEREFERENCE:
7436                 return true;
7437
7438         default:
7439                 return false;
7440         }
7441 }
7442
7443 static void semantic_incdec(unary_expression_t *expression)
7444 {
7445         type_t *const orig_type = expression->value->base.type;
7446         type_t *const type      = skip_typeref(orig_type);
7447         if (is_type_pointer(type)) {
7448                 if (!check_pointer_arithmetic(&expression->base.source_position,
7449                                               type, orig_type)) {
7450                         return;
7451                 }
7452         } else if (!is_type_real(type) && is_type_valid(type)) {
7453                 /* TODO: improve error message */
7454                 errorf(&expression->base.source_position,
7455                        "operation needs an arithmetic or pointer type");
7456                 return;
7457         }
7458         if (!is_lvalue(expression->value)) {
7459                 /* TODO: improve error message */
7460                 errorf(&expression->base.source_position, "lvalue required as operand");
7461         }
7462         expression->base.type = orig_type;
7463 }
7464
7465 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
7466 {
7467         type_t *const orig_type = expression->value->base.type;
7468         type_t *const type      = skip_typeref(orig_type);
7469         if (!is_type_arithmetic(type)) {
7470                 if (is_type_valid(type)) {
7471                         /* TODO: improve error message */
7472                         errorf(&expression->base.source_position,
7473                                 "operation needs an arithmetic type");
7474                 }
7475                 return;
7476         }
7477
7478         expression->base.type = orig_type;
7479 }
7480
7481 static void semantic_unexpr_plus(unary_expression_t *expression)
7482 {
7483         semantic_unexpr_arithmetic(expression);
7484         if (warning.traditional)
7485                 warningf(&expression->base.source_position,
7486                         "traditional C rejects the unary plus operator");
7487 }
7488
7489 static void semantic_not(unary_expression_t *expression)
7490 {
7491         type_t *const orig_type = expression->value->base.type;
7492         type_t *const type      = skip_typeref(orig_type);
7493         if (!is_type_scalar(type) && is_type_valid(type)) {
7494                 errorf(&expression->base.source_position,
7495                        "operand of ! must be of scalar type");
7496         }
7497
7498         expression->base.type = type_int;
7499 }
7500
7501 static void semantic_unexpr_integer(unary_expression_t *expression)
7502 {
7503         type_t *const orig_type = expression->value->base.type;
7504         type_t *const type      = skip_typeref(orig_type);
7505         if (!is_type_integer(type)) {
7506                 if (is_type_valid(type)) {
7507                         errorf(&expression->base.source_position,
7508                                "operand of ~ must be of integer type");
7509                 }
7510                 return;
7511         }
7512
7513         expression->base.type = orig_type;
7514 }
7515
7516 static void semantic_dereference(unary_expression_t *expression)
7517 {
7518         type_t *const orig_type = expression->value->base.type;
7519         type_t *const type      = skip_typeref(orig_type);
7520         if (!is_type_pointer(type)) {
7521                 if (is_type_valid(type)) {
7522                         errorf(&expression->base.source_position,
7523                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
7524                 }
7525                 return;
7526         }
7527
7528         type_t *result_type   = type->pointer.points_to;
7529         result_type           = automatic_type_conversion(result_type);
7530         expression->base.type = result_type;
7531 }
7532
7533 /**
7534  * Record that an address is taken (expression represents an lvalue).
7535  *
7536  * @param expression       the expression
7537  * @param may_be_register  if true, the expression might be an register
7538  */
7539 static void set_address_taken(expression_t *expression, bool may_be_register)
7540 {
7541         if (expression->kind != EXPR_REFERENCE)
7542                 return;
7543
7544         declaration_t *const declaration = expression->reference.declaration;
7545         /* happens for parse errors */
7546         if (declaration == NULL)
7547                 return;
7548
7549         if (declaration->storage_class == STORAGE_CLASS_REGISTER && !may_be_register) {
7550                 errorf(&expression->base.source_position,
7551                                 "address of register variable '%Y' requested",
7552                                 declaration->symbol);
7553         } else {
7554                 declaration->address_taken = 1;
7555         }
7556 }
7557
7558 /**
7559  * Check the semantic of the address taken expression.
7560  */
7561 static void semantic_take_addr(unary_expression_t *expression)
7562 {
7563         expression_t *value = expression->value;
7564         value->base.type    = revert_automatic_type_conversion(value);
7565
7566         type_t *orig_type = value->base.type;
7567         if (!is_type_valid(orig_type))
7568                 return;
7569
7570         set_address_taken(value, false);
7571
7572         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
7573 }
7574
7575 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc)   \
7576 static expression_t *parse_##unexpression_type(unsigned precedence)            \
7577 {                                                                              \
7578         expression_t *unary_expression                                             \
7579                 = allocate_expression_zero(unexpression_type);                         \
7580         unary_expression->base.source_position = *HERE;                            \
7581         eat(token_type);                                                           \
7582         unary_expression->unary.value = parse_sub_expression(precedence);          \
7583                                                                                    \
7584         sfunc(&unary_expression->unary);                                           \
7585                                                                                    \
7586         return unary_expression;                                                   \
7587 }
7588
7589 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
7590                                semantic_unexpr_arithmetic)
7591 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
7592                                semantic_unexpr_plus)
7593 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
7594                                semantic_not)
7595 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
7596                                semantic_dereference)
7597 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
7598                                semantic_take_addr)
7599 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
7600                                semantic_unexpr_integer)
7601 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
7602                                semantic_incdec)
7603 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
7604                                semantic_incdec)
7605
7606 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
7607                                                sfunc)                         \
7608 static expression_t *parse_##unexpression_type(unsigned precedence,           \
7609                                                expression_t *left)            \
7610 {                                                                             \
7611         (void) precedence;                                                        \
7612                                                                               \
7613         expression_t *unary_expression                                            \
7614                 = allocate_expression_zero(unexpression_type);                        \
7615         unary_expression->base.source_position = *HERE;                           \
7616         eat(token_type);                                                          \
7617         unary_expression->unary.value          = left;                            \
7618                                                                                   \
7619         sfunc(&unary_expression->unary);                                          \
7620                                                                               \
7621         return unary_expression;                                                  \
7622 }
7623
7624 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
7625                                        EXPR_UNARY_POSTFIX_INCREMENT,
7626                                        semantic_incdec)
7627 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
7628                                        EXPR_UNARY_POSTFIX_DECREMENT,
7629                                        semantic_incdec)
7630
7631 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
7632 {
7633         /* TODO: handle complex + imaginary types */
7634
7635         type_left  = get_unqualified_type(type_left);
7636         type_right = get_unqualified_type(type_right);
7637
7638         /* § 6.3.1.8 Usual arithmetic conversions */
7639         if (type_left == type_long_double || type_right == type_long_double) {
7640                 return type_long_double;
7641         } else if (type_left == type_double || type_right == type_double) {
7642                 return type_double;
7643         } else if (type_left == type_float || type_right == type_float) {
7644                 return type_float;
7645         }
7646
7647         type_left  = promote_integer(type_left);
7648         type_right = promote_integer(type_right);
7649
7650         if (type_left == type_right)
7651                 return type_left;
7652
7653         bool const signed_left  = is_type_signed(type_left);
7654         bool const signed_right = is_type_signed(type_right);
7655         int const  rank_left    = get_rank(type_left);
7656         int const  rank_right   = get_rank(type_right);
7657
7658         if (signed_left == signed_right)
7659                 return rank_left >= rank_right ? type_left : type_right;
7660
7661         int     s_rank;
7662         int     u_rank;
7663         type_t *s_type;
7664         type_t *u_type;
7665         if (signed_left) {
7666                 s_rank = rank_left;
7667                 s_type = type_left;
7668                 u_rank = rank_right;
7669                 u_type = type_right;
7670         } else {
7671                 s_rank = rank_right;
7672                 s_type = type_right;
7673                 u_rank = rank_left;
7674                 u_type = type_left;
7675         }
7676
7677         if (u_rank >= s_rank)
7678                 return u_type;
7679
7680         /* casting rank to atomic_type_kind is a bit hacky, but makes things
7681          * easier here... */
7682         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
7683                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
7684                 return s_type;
7685
7686         switch (s_rank) {
7687                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
7688                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
7689                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
7690
7691                 default: panic("invalid atomic type");
7692         }
7693 }
7694
7695 /**
7696  * Check the semantic restrictions for a binary expression.
7697  */
7698 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
7699 {
7700         expression_t *const left            = expression->left;
7701         expression_t *const right           = expression->right;
7702         type_t       *const orig_type_left  = left->base.type;
7703         type_t       *const orig_type_right = right->base.type;
7704         type_t       *const type_left       = skip_typeref(orig_type_left);
7705         type_t       *const type_right      = skip_typeref(orig_type_right);
7706
7707         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7708                 /* TODO: improve error message */
7709                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7710                         errorf(&expression->base.source_position,
7711                                "operation needs arithmetic types");
7712                 }
7713                 return;
7714         }
7715
7716         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7717         expression->left      = create_implicit_cast(left, arithmetic_type);
7718         expression->right     = create_implicit_cast(right, arithmetic_type);
7719         expression->base.type = arithmetic_type;
7720 }
7721
7722 static void warn_div_by_zero(binary_expression_t const *const expression)
7723 {
7724         if (!warning.div_by_zero ||
7725             !is_type_integer(expression->base.type))
7726                 return;
7727
7728         expression_t const *const right = expression->right;
7729         /* The type of the right operand can be different for /= */
7730         if (is_type_integer(right->base.type) &&
7731             is_constant_expression(right)     &&
7732             fold_constant(right) == 0) {
7733                 warningf(&expression->base.source_position, "division by zero");
7734         }
7735 }
7736
7737 /**
7738  * Check the semantic restrictions for a div/mod expression.
7739  */
7740 static void semantic_divmod_arithmetic(binary_expression_t *expression) {
7741         semantic_binexpr_arithmetic(expression);
7742         warn_div_by_zero(expression);
7743 }
7744
7745 static void semantic_shift_op(binary_expression_t *expression)
7746 {
7747         expression_t *const left            = expression->left;
7748         expression_t *const right           = expression->right;
7749         type_t       *const orig_type_left  = left->base.type;
7750         type_t       *const orig_type_right = right->base.type;
7751         type_t       *      type_left       = skip_typeref(orig_type_left);
7752         type_t       *      type_right      = skip_typeref(orig_type_right);
7753
7754         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
7755                 /* TODO: improve error message */
7756                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7757                         errorf(&expression->base.source_position,
7758                                "operands of shift operation must have integer types");
7759                 }
7760                 return;
7761         }
7762
7763         type_left  = promote_integer(type_left);
7764         type_right = promote_integer(type_right);
7765
7766         expression->left      = create_implicit_cast(left, type_left);
7767         expression->right     = create_implicit_cast(right, type_right);
7768         expression->base.type = type_left;
7769 }
7770
7771 static void semantic_add(binary_expression_t *expression)
7772 {
7773         expression_t *const left            = expression->left;
7774         expression_t *const right           = expression->right;
7775         type_t       *const orig_type_left  = left->base.type;
7776         type_t       *const orig_type_right = right->base.type;
7777         type_t       *const type_left       = skip_typeref(orig_type_left);
7778         type_t       *const type_right      = skip_typeref(orig_type_right);
7779
7780         /* § 6.5.6 */
7781         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7782                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7783                 expression->left  = create_implicit_cast(left, arithmetic_type);
7784                 expression->right = create_implicit_cast(right, arithmetic_type);
7785                 expression->base.type = arithmetic_type;
7786                 return;
7787         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7788                 check_pointer_arithmetic(&expression->base.source_position,
7789                                          type_left, orig_type_left);
7790                 expression->base.type = type_left;
7791         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
7792                 check_pointer_arithmetic(&expression->base.source_position,
7793                                          type_right, orig_type_right);
7794                 expression->base.type = type_right;
7795         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7796                 errorf(&expression->base.source_position,
7797                        "invalid operands to binary + ('%T', '%T')",
7798                        orig_type_left, orig_type_right);
7799         }
7800 }
7801
7802 static void semantic_sub(binary_expression_t *expression)
7803 {
7804         expression_t            *const left            = expression->left;
7805         expression_t            *const right           = expression->right;
7806         type_t                  *const orig_type_left  = left->base.type;
7807         type_t                  *const orig_type_right = right->base.type;
7808         type_t                  *const type_left       = skip_typeref(orig_type_left);
7809         type_t                  *const type_right      = skip_typeref(orig_type_right);
7810         source_position_t const *const pos             = &expression->base.source_position;
7811
7812         /* § 5.6.5 */
7813         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7814                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7815                 expression->left        = create_implicit_cast(left, arithmetic_type);
7816                 expression->right       = create_implicit_cast(right, arithmetic_type);
7817                 expression->base.type =  arithmetic_type;
7818                 return;
7819         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
7820                 check_pointer_arithmetic(&expression->base.source_position,
7821                                          type_left, orig_type_left);
7822                 expression->base.type = type_left;
7823         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7824                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
7825                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
7826                 if (!types_compatible(unqual_left, unqual_right)) {
7827                         errorf(pos,
7828                                "subtracting pointers to incompatible types '%T' and '%T'",
7829                                orig_type_left, orig_type_right);
7830                 } else if (!is_type_object(unqual_left)) {
7831                         if (is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
7832                                 warningf(pos, "subtracting pointers to void");
7833                         } else {
7834                                 errorf(pos, "subtracting pointers to non-object types '%T'",
7835                                        orig_type_left);
7836                         }
7837                 }
7838                 expression->base.type = type_ptrdiff_t;
7839         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7840                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
7841                        orig_type_left, orig_type_right);
7842         }
7843 }
7844
7845 /**
7846  * Check the semantics of comparison expressions.
7847  *
7848  * @param expression   The expression to check.
7849  */
7850 static void semantic_comparison(binary_expression_t *expression)
7851 {
7852         expression_t *left            = expression->left;
7853         expression_t *right           = expression->right;
7854         type_t       *orig_type_left  = left->base.type;
7855         type_t       *orig_type_right = right->base.type;
7856
7857         type_t *type_left  = skip_typeref(orig_type_left);
7858         type_t *type_right = skip_typeref(orig_type_right);
7859
7860         /* TODO non-arithmetic types */
7861         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
7862                 /* test for signed vs unsigned compares */
7863                 if (warning.sign_compare &&
7864                     (expression->base.kind != EXPR_BINARY_EQUAL &&
7865                      expression->base.kind != EXPR_BINARY_NOTEQUAL) &&
7866                     (is_type_signed(type_left) != is_type_signed(type_right))) {
7867
7868                         /* check if 1 of the operands is a constant, in this case we just
7869                          * check wether we can safely represent the resulting constant in
7870                          * the type of the other operand. */
7871                         expression_t *const_expr = NULL;
7872                         expression_t *other_expr = NULL;
7873
7874                         if (is_constant_expression(left)) {
7875                                 const_expr = left;
7876                                 other_expr = right;
7877                         } else if (is_constant_expression(right)) {
7878                                 const_expr = right;
7879                                 other_expr = left;
7880                         }
7881
7882                         if (const_expr != NULL) {
7883                                 type_t *other_type = skip_typeref(other_expr->base.type);
7884                                 long    val        = fold_constant(const_expr);
7885                                 /* TODO: check if val can be represented by other_type */
7886                                 (void) other_type;
7887                                 (void) val;
7888                         }
7889                         warningf(&expression->base.source_position,
7890                                  "comparison between signed and unsigned");
7891                 }
7892                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7893                 expression->left        = create_implicit_cast(left, arithmetic_type);
7894                 expression->right       = create_implicit_cast(right, arithmetic_type);
7895                 expression->base.type   = arithmetic_type;
7896                 if (warning.float_equal &&
7897                     (expression->base.kind == EXPR_BINARY_EQUAL ||
7898                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
7899                     is_type_float(arithmetic_type)) {
7900                         warningf(&expression->base.source_position,
7901                                  "comparing floating point with == or != is unsafe");
7902                 }
7903         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
7904                 /* TODO check compatibility */
7905         } else if (is_type_pointer(type_left)) {
7906                 expression->right = create_implicit_cast(right, type_left);
7907         } else if (is_type_pointer(type_right)) {
7908                 expression->left = create_implicit_cast(left, type_right);
7909         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
7910                 type_error_incompatible("invalid operands in comparison",
7911                                         &expression->base.source_position,
7912                                         type_left, type_right);
7913         }
7914         expression->base.type = type_int;
7915 }
7916
7917 /**
7918  * Checks if a compound type has constant fields.
7919  */
7920 static bool has_const_fields(const compound_type_t *type)
7921 {
7922         const scope_t       *scope       = &type->declaration->scope;
7923         const declaration_t *declaration = scope->declarations;
7924
7925         for (; declaration != NULL; declaration = declaration->next) {
7926                 if (declaration->namespc != NAMESPACE_NORMAL)
7927                         continue;
7928
7929                 const type_t *decl_type = skip_typeref(declaration->type);
7930                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
7931                         return true;
7932         }
7933         /* TODO */
7934         return false;
7935 }
7936
7937 static bool is_valid_assignment_lhs(expression_t const* const left)
7938 {
7939         type_t *const orig_type_left = revert_automatic_type_conversion(left);
7940         type_t *const type_left      = skip_typeref(orig_type_left);
7941
7942         if (!is_lvalue(left)) {
7943                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
7944                        left);
7945                 return false;
7946         }
7947
7948         if (is_type_array(type_left)) {
7949                 errorf(HERE, "cannot assign to arrays ('%E')", left);
7950                 return false;
7951         }
7952         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
7953                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
7954                        orig_type_left);
7955                 return false;
7956         }
7957         if (is_type_incomplete(type_left)) {
7958                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
7959                        left, orig_type_left);
7960                 return false;
7961         }
7962         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
7963                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
7964                        left, orig_type_left);
7965                 return false;
7966         }
7967
7968         return true;
7969 }
7970
7971 static void semantic_arithmetic_assign(binary_expression_t *expression)
7972 {
7973         expression_t *left            = expression->left;
7974         expression_t *right           = expression->right;
7975         type_t       *orig_type_left  = left->base.type;
7976         type_t       *orig_type_right = right->base.type;
7977
7978         if (!is_valid_assignment_lhs(left))
7979                 return;
7980
7981         type_t *type_left  = skip_typeref(orig_type_left);
7982         type_t *type_right = skip_typeref(orig_type_right);
7983
7984         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
7985                 /* TODO: improve error message */
7986                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
7987                         errorf(&expression->base.source_position,
7988                                "operation needs arithmetic types");
7989                 }
7990                 return;
7991         }
7992
7993         /* combined instructions are tricky. We can't create an implicit cast on
7994          * the left side, because we need the uncasted form for the store.
7995          * The ast2firm pass has to know that left_type must be right_type
7996          * for the arithmetic operation and create a cast by itself */
7997         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
7998         expression->right       = create_implicit_cast(right, arithmetic_type);
7999         expression->base.type   = type_left;
8000 }
8001
8002 static void semantic_divmod_assign(binary_expression_t *expression)
8003 {
8004         semantic_arithmetic_assign(expression);
8005         warn_div_by_zero(expression);
8006 }
8007
8008 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
8009 {
8010         expression_t *const left            = expression->left;
8011         expression_t *const right           = expression->right;
8012         type_t       *const orig_type_left  = left->base.type;
8013         type_t       *const orig_type_right = right->base.type;
8014         type_t       *const type_left       = skip_typeref(orig_type_left);
8015         type_t       *const type_right      = skip_typeref(orig_type_right);
8016
8017         if (!is_valid_assignment_lhs(left))
8018                 return;
8019
8020         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8021                 /* combined instructions are tricky. We can't create an implicit cast on
8022                  * the left side, because we need the uncasted form for the store.
8023                  * The ast2firm pass has to know that left_type must be right_type
8024                  * for the arithmetic operation and create a cast by itself */
8025                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
8026                 expression->right     = create_implicit_cast(right, arithmetic_type);
8027                 expression->base.type = type_left;
8028         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8029                 check_pointer_arithmetic(&expression->base.source_position,
8030                                          type_left, orig_type_left);
8031                 expression->base.type = type_left;
8032         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8033                 errorf(&expression->base.source_position,
8034                        "incompatible types '%T' and '%T' in assignment",
8035                        orig_type_left, orig_type_right);
8036         }
8037 }
8038
8039 /**
8040  * Check the semantic restrictions of a logical expression.
8041  */
8042 static void semantic_logical_op(binary_expression_t *expression)
8043 {
8044         expression_t *const left            = expression->left;
8045         expression_t *const right           = expression->right;
8046         type_t       *const orig_type_left  = left->base.type;
8047         type_t       *const orig_type_right = right->base.type;
8048         type_t       *const type_left       = skip_typeref(orig_type_left);
8049         type_t       *const type_right      = skip_typeref(orig_type_right);
8050
8051         if (!is_type_scalar(type_left) || !is_type_scalar(type_right)) {
8052                 /* TODO: improve error message */
8053                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8054                         errorf(&expression->base.source_position,
8055                                "operation needs scalar types");
8056                 }
8057                 return;
8058         }
8059
8060         expression->base.type = type_int;
8061 }
8062
8063 /**
8064  * Check the semantic restrictions of a binary assign expression.
8065  */
8066 static void semantic_binexpr_assign(binary_expression_t *expression)
8067 {
8068         expression_t *left           = expression->left;
8069         type_t       *orig_type_left = left->base.type;
8070
8071         if (!is_valid_assignment_lhs(left))
8072                 return;
8073
8074         assign_error_t error = semantic_assign(orig_type_left, expression->right);
8075         report_assign_error(error, orig_type_left, expression->right,
8076                         "assignment", &left->base.source_position);
8077         expression->right = create_implicit_cast(expression->right, orig_type_left);
8078         expression->base.type = orig_type_left;
8079 }
8080
8081 /**
8082  * Determine if the outermost operation (or parts thereof) of the given
8083  * expression has no effect in order to generate a warning about this fact.
8084  * Therefore in some cases this only examines some of the operands of the
8085  * expression (see comments in the function and examples below).
8086  * Examples:
8087  *   f() + 23;    // warning, because + has no effect
8088  *   x || f();    // no warning, because x controls execution of f()
8089  *   x ? y : f(); // warning, because y has no effect
8090  *   (void)x;     // no warning to be able to suppress the warning
8091  * This function can NOT be used for an "expression has definitely no effect"-
8092  * analysis. */
8093 static bool expression_has_effect(const expression_t *const expr)
8094 {
8095         switch (expr->kind) {
8096                 case EXPR_UNKNOWN:                   break;
8097                 case EXPR_INVALID:                   return true; /* do NOT warn */
8098                 case EXPR_REFERENCE:                 return false;
8099                 /* suppress the warning for microsoft __noop operations */
8100                 case EXPR_CONST:                     return expr->conste.is_ms_noop;
8101                 case EXPR_CHARACTER_CONSTANT:        return false;
8102                 case EXPR_WIDE_CHARACTER_CONSTANT:   return false;
8103                 case EXPR_STRING_LITERAL:            return false;
8104                 case EXPR_WIDE_STRING_LITERAL:       return false;
8105                 case EXPR_LABEL_ADDRESS:             return false;
8106
8107                 case EXPR_CALL: {
8108                         const call_expression_t *const call = &expr->call;
8109                         if (call->function->kind != EXPR_BUILTIN_SYMBOL)
8110                                 return true;
8111
8112                         switch (call->function->builtin_symbol.symbol->ID) {
8113                                 case T___builtin_va_end: return true;
8114                                 default:                 return false;
8115                         }
8116                 }
8117
8118                 /* Generate the warning if either the left or right hand side of a
8119                  * conditional expression has no effect */
8120                 case EXPR_CONDITIONAL: {
8121                         const conditional_expression_t *const cond = &expr->conditional;
8122                         return
8123                                 expression_has_effect(cond->true_expression) &&
8124                                 expression_has_effect(cond->false_expression);
8125                 }
8126
8127                 case EXPR_SELECT:                    return false;
8128                 case EXPR_ARRAY_ACCESS:              return false;
8129                 case EXPR_SIZEOF:                    return false;
8130                 case EXPR_CLASSIFY_TYPE:             return false;
8131                 case EXPR_ALIGNOF:                   return false;
8132
8133                 case EXPR_FUNCNAME:                  return false;
8134                 case EXPR_BUILTIN_SYMBOL:            break; /* handled in EXPR_CALL */
8135                 case EXPR_BUILTIN_CONSTANT_P:        return false;
8136                 case EXPR_BUILTIN_PREFETCH:          return true;
8137                 case EXPR_OFFSETOF:                  return false;
8138                 case EXPR_VA_START:                  return true;
8139                 case EXPR_VA_ARG:                    return true;
8140                 case EXPR_STATEMENT:                 return true; // TODO
8141                 case EXPR_COMPOUND_LITERAL:          return false;
8142
8143                 case EXPR_UNARY_NEGATE:              return false;
8144                 case EXPR_UNARY_PLUS:                return false;
8145                 case EXPR_UNARY_BITWISE_NEGATE:      return false;
8146                 case EXPR_UNARY_NOT:                 return false;
8147                 case EXPR_UNARY_DEREFERENCE:         return false;
8148                 case EXPR_UNARY_TAKE_ADDRESS:        return false;
8149                 case EXPR_UNARY_POSTFIX_INCREMENT:   return true;
8150                 case EXPR_UNARY_POSTFIX_DECREMENT:   return true;
8151                 case EXPR_UNARY_PREFIX_INCREMENT:    return true;
8152                 case EXPR_UNARY_PREFIX_DECREMENT:    return true;
8153
8154                 /* Treat void casts as if they have an effect in order to being able to
8155                  * suppress the warning */
8156                 case EXPR_UNARY_CAST: {
8157                         type_t *const type = skip_typeref(expr->base.type);
8158                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
8159                 }
8160
8161                 case EXPR_UNARY_CAST_IMPLICIT:       return true;
8162                 case EXPR_UNARY_ASSUME:              return true;
8163
8164                 case EXPR_BINARY_ADD:                return false;
8165                 case EXPR_BINARY_SUB:                return false;
8166                 case EXPR_BINARY_MUL:                return false;
8167                 case EXPR_BINARY_DIV:                return false;
8168                 case EXPR_BINARY_MOD:                return false;
8169                 case EXPR_BINARY_EQUAL:              return false;
8170                 case EXPR_BINARY_NOTEQUAL:           return false;
8171                 case EXPR_BINARY_LESS:               return false;
8172                 case EXPR_BINARY_LESSEQUAL:          return false;
8173                 case EXPR_BINARY_GREATER:            return false;
8174                 case EXPR_BINARY_GREATEREQUAL:       return false;
8175                 case EXPR_BINARY_BITWISE_AND:        return false;
8176                 case EXPR_BINARY_BITWISE_OR:         return false;
8177                 case EXPR_BINARY_BITWISE_XOR:        return false;
8178                 case EXPR_BINARY_SHIFTLEFT:          return false;
8179                 case EXPR_BINARY_SHIFTRIGHT:         return false;
8180                 case EXPR_BINARY_ASSIGN:             return true;
8181                 case EXPR_BINARY_MUL_ASSIGN:         return true;
8182                 case EXPR_BINARY_DIV_ASSIGN:         return true;
8183                 case EXPR_BINARY_MOD_ASSIGN:         return true;
8184                 case EXPR_BINARY_ADD_ASSIGN:         return true;
8185                 case EXPR_BINARY_SUB_ASSIGN:         return true;
8186                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:   return true;
8187                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:  return true;
8188                 case EXPR_BINARY_BITWISE_AND_ASSIGN: return true;
8189                 case EXPR_BINARY_BITWISE_XOR_ASSIGN: return true;
8190                 case EXPR_BINARY_BITWISE_OR_ASSIGN:  return true;
8191
8192                 /* Only examine the right hand side of && and ||, because the left hand
8193                  * side already has the effect of controlling the execution of the right
8194                  * hand side */
8195                 case EXPR_BINARY_LOGICAL_AND:
8196                 case EXPR_BINARY_LOGICAL_OR:
8197                 /* Only examine the right hand side of a comma expression, because the left
8198                  * hand side has a separate warning */
8199                 case EXPR_BINARY_COMMA:
8200                         return expression_has_effect(expr->binary.right);
8201
8202                 case EXPR_BINARY_BUILTIN_EXPECT:     return true;
8203                 case EXPR_BINARY_ISGREATER:          return false;
8204                 case EXPR_BINARY_ISGREATEREQUAL:     return false;
8205                 case EXPR_BINARY_ISLESS:             return false;
8206                 case EXPR_BINARY_ISLESSEQUAL:        return false;
8207                 case EXPR_BINARY_ISLESSGREATER:      return false;
8208                 case EXPR_BINARY_ISUNORDERED:        return false;
8209         }
8210
8211         internal_errorf(HERE, "unexpected expression");
8212 }
8213
8214 static void semantic_comma(binary_expression_t *expression)
8215 {
8216         if (warning.unused_value) {
8217                 const expression_t *const left = expression->left;
8218                 if (!expression_has_effect(left)) {
8219                         warningf(&left->base.source_position,
8220                                  "left-hand operand of comma expression has no effect");
8221                 }
8222         }
8223         expression->base.type = expression->right->base.type;
8224 }
8225
8226 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, sfunc, lr)  \
8227 static expression_t *parse_##binexpression_type(unsigned precedence,      \
8228                                                 expression_t *left)       \
8229 {                                                                         \
8230         expression_t *binexpr = allocate_expression_zero(binexpression_type); \
8231         binexpr->base.source_position = *HERE;                                \
8232         binexpr->binary.left          = left;                                 \
8233         eat(token_type);                                                      \
8234                                                                           \
8235         expression_t *right = parse_sub_expression(precedence + lr);          \
8236                                                                           \
8237         binexpr->binary.right = right;                                        \
8238         sfunc(&binexpr->binary);                                              \
8239                                                                           \
8240         return binexpr;                                                       \
8241 }
8242
8243 CREATE_BINEXPR_PARSER(',', EXPR_BINARY_COMMA,    semantic_comma, 1)
8244 CREATE_BINEXPR_PARSER('*', EXPR_BINARY_MUL,      semantic_binexpr_arithmetic, 1)
8245 CREATE_BINEXPR_PARSER('/', EXPR_BINARY_DIV,      semantic_divmod_arithmetic, 1)
8246 CREATE_BINEXPR_PARSER('%', EXPR_BINARY_MOD,      semantic_divmod_arithmetic, 1)
8247 CREATE_BINEXPR_PARSER('+', EXPR_BINARY_ADD,      semantic_add, 1)
8248 CREATE_BINEXPR_PARSER('-', EXPR_BINARY_SUB,      semantic_sub, 1)
8249 CREATE_BINEXPR_PARSER('<', EXPR_BINARY_LESS,     semantic_comparison, 1)
8250 CREATE_BINEXPR_PARSER('>', EXPR_BINARY_GREATER,  semantic_comparison, 1)
8251 CREATE_BINEXPR_PARSER('=', EXPR_BINARY_ASSIGN,   semantic_binexpr_assign, 0)
8252
8253 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,
8254                       semantic_comparison, 1)
8255 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,
8256                       semantic_comparison, 1)
8257 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,
8258                       semantic_comparison, 1)
8259 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,
8260                       semantic_comparison, 1)
8261
8262 CREATE_BINEXPR_PARSER('&', EXPR_BINARY_BITWISE_AND,
8263                       semantic_binexpr_arithmetic, 1)
8264 CREATE_BINEXPR_PARSER('|', EXPR_BINARY_BITWISE_OR,
8265                       semantic_binexpr_arithmetic, 1)
8266 CREATE_BINEXPR_PARSER('^', EXPR_BINARY_BITWISE_XOR,
8267                       semantic_binexpr_arithmetic, 1)
8268 CREATE_BINEXPR_PARSER(T_ANDAND, EXPR_BINARY_LOGICAL_AND,
8269                       semantic_logical_op, 1)
8270 CREATE_BINEXPR_PARSER(T_PIPEPIPE, EXPR_BINARY_LOGICAL_OR,
8271                       semantic_logical_op, 1)
8272 CREATE_BINEXPR_PARSER(T_LESSLESS, EXPR_BINARY_SHIFTLEFT,
8273                       semantic_shift_op, 1)
8274 CREATE_BINEXPR_PARSER(T_GREATERGREATER, EXPR_BINARY_SHIFTRIGHT,
8275                       semantic_shift_op, 1)
8276 CREATE_BINEXPR_PARSER(T_PLUSEQUAL, EXPR_BINARY_ADD_ASSIGN,
8277                       semantic_arithmetic_addsubb_assign, 0)
8278 CREATE_BINEXPR_PARSER(T_MINUSEQUAL, EXPR_BINARY_SUB_ASSIGN,
8279                       semantic_arithmetic_addsubb_assign, 0)
8280 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL, EXPR_BINARY_MUL_ASSIGN,
8281                       semantic_arithmetic_assign, 0)
8282 CREATE_BINEXPR_PARSER(T_SLASHEQUAL, EXPR_BINARY_DIV_ASSIGN,
8283                       semantic_divmod_assign, 0)
8284 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL, EXPR_BINARY_MOD_ASSIGN,
8285                       semantic_divmod_assign, 0)
8286 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL, EXPR_BINARY_SHIFTLEFT_ASSIGN,
8287                       semantic_arithmetic_assign, 0)
8288 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL, EXPR_BINARY_SHIFTRIGHT_ASSIGN,
8289                       semantic_arithmetic_assign, 0)
8290 CREATE_BINEXPR_PARSER(T_ANDEQUAL, EXPR_BINARY_BITWISE_AND_ASSIGN,
8291                       semantic_arithmetic_assign, 0)
8292 CREATE_BINEXPR_PARSER(T_PIPEEQUAL, EXPR_BINARY_BITWISE_OR_ASSIGN,
8293                       semantic_arithmetic_assign, 0)
8294 CREATE_BINEXPR_PARSER(T_CARETEQUAL, EXPR_BINARY_BITWISE_XOR_ASSIGN,
8295                       semantic_arithmetic_assign, 0)
8296
8297 static expression_t *parse_sub_expression(unsigned precedence)
8298 {
8299         if (token.type < 0) {
8300                 return expected_expression_error();
8301         }
8302
8303         expression_parser_function_t *parser
8304                 = &expression_parsers[token.type];
8305         source_position_t             source_position = token.source_position;
8306         expression_t                 *left;
8307
8308         if (parser->parser != NULL) {
8309                 left = parser->parser(parser->precedence);
8310         } else {
8311                 left = parse_primary_expression();
8312         }
8313         assert(left != NULL);
8314         left->base.source_position = source_position;
8315
8316         while(true) {
8317                 if (token.type < 0) {
8318                         return expected_expression_error();
8319                 }
8320
8321                 parser = &expression_parsers[token.type];
8322                 if (parser->infix_parser == NULL)
8323                         break;
8324                 if (parser->infix_precedence < precedence)
8325                         break;
8326
8327                 left = parser->infix_parser(parser->infix_precedence, left);
8328
8329                 assert(left != NULL);
8330                 assert(left->kind != EXPR_UNKNOWN);
8331                 left->base.source_position = source_position;
8332         }
8333
8334         return left;
8335 }
8336
8337 /**
8338  * Parse an expression.
8339  */
8340 static expression_t *parse_expression(void)
8341 {
8342         return parse_sub_expression(1);
8343 }
8344
8345 /**
8346  * Register a parser for a prefix-like operator with given precedence.
8347  *
8348  * @param parser      the parser function
8349  * @param token_type  the token type of the prefix token
8350  * @param precedence  the precedence of the operator
8351  */
8352 static void register_expression_parser(parse_expression_function parser,
8353                                        int token_type, unsigned precedence)
8354 {
8355         expression_parser_function_t *entry = &expression_parsers[token_type];
8356
8357         if (entry->parser != NULL) {
8358                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8359                 panic("trying to register multiple expression parsers for a token");
8360         }
8361         entry->parser     = parser;
8362         entry->precedence = precedence;
8363 }
8364
8365 /**
8366  * Register a parser for an infix operator with given precedence.
8367  *
8368  * @param parser      the parser function
8369  * @param token_type  the token type of the infix operator
8370  * @param precedence  the precedence of the operator
8371  */
8372 static void register_infix_parser(parse_expression_infix_function parser,
8373                 int token_type, unsigned precedence)
8374 {
8375         expression_parser_function_t *entry = &expression_parsers[token_type];
8376
8377         if (entry->infix_parser != NULL) {
8378                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8379                 panic("trying to register multiple infix expression parsers for a "
8380                       "token");
8381         }
8382         entry->infix_parser     = parser;
8383         entry->infix_precedence = precedence;
8384 }
8385
8386 /**
8387  * Initialize the expression parsers.
8388  */
8389 static void init_expression_parsers(void)
8390 {
8391         memset(&expression_parsers, 0, sizeof(expression_parsers));
8392
8393         register_infix_parser(parse_array_expression,         '[',              30);
8394         register_infix_parser(parse_call_expression,          '(',              30);
8395         register_infix_parser(parse_select_expression,        '.',              30);
8396         register_infix_parser(parse_select_expression,        T_MINUSGREATER,   30);
8397         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,
8398                                                               T_PLUSPLUS,       30);
8399         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,
8400                                                               T_MINUSMINUS,     30);
8401
8402         register_infix_parser(parse_EXPR_BINARY_MUL,          '*',              17);
8403         register_infix_parser(parse_EXPR_BINARY_DIV,          '/',              17);
8404         register_infix_parser(parse_EXPR_BINARY_MOD,          '%',              17);
8405         register_infix_parser(parse_EXPR_BINARY_ADD,          '+',              16);
8406         register_infix_parser(parse_EXPR_BINARY_SUB,          '-',              16);
8407         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,    T_LESSLESS,       15);
8408         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,   T_GREATERGREATER, 15);
8409         register_infix_parser(parse_EXPR_BINARY_LESS,         '<',              14);
8410         register_infix_parser(parse_EXPR_BINARY_GREATER,      '>',              14);
8411         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,    T_LESSEQUAL,      14);
8412         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL, T_GREATEREQUAL,   14);
8413         register_infix_parser(parse_EXPR_BINARY_EQUAL,        T_EQUALEQUAL,     13);
8414         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,
8415                                                     T_EXCLAMATIONMARKEQUAL, 13);
8416         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,  '&',              12);
8417         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,  '^',              11);
8418         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,   '|',              10);
8419         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,  T_ANDAND,          9);
8420         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,   T_PIPEPIPE,        8);
8421         register_infix_parser(parse_conditional_expression,   '?',               7);
8422         register_infix_parser(parse_EXPR_BINARY_ASSIGN,       '=',               2);
8423         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,   T_PLUSEQUAL,       2);
8424         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,   T_MINUSEQUAL,      2);
8425         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,   T_ASTERISKEQUAL,   2);
8426         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,   T_SLASHEQUAL,      2);
8427         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,   T_PERCENTEQUAL,    2);
8428         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,
8429                                                                 T_LESSLESSEQUAL, 2);
8430         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,
8431                                                           T_GREATERGREATEREQUAL, 2);
8432         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN,
8433                                                                      T_ANDEQUAL, 2);
8434         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,
8435                                                                     T_PIPEEQUAL, 2);
8436         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN,
8437                                                                    T_CARETEQUAL, 2);
8438
8439         register_infix_parser(parse_EXPR_BINARY_COMMA,        ',',               1);
8440
8441         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-',      25);
8442         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+',      25);
8443         register_expression_parser(parse_EXPR_UNARY_NOT,              '!',      25);
8444         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~',      25);
8445         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*',      25);
8446         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&',      25);
8447         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT,
8448                                                                   T_PLUSPLUS,   25);
8449         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT,
8450                                                                   T_MINUSMINUS, 25);
8451         register_expression_parser(parse_sizeof,                      T_sizeof, 25);
8452         register_expression_parser(parse_alignof,                T___alignof__, 25);
8453         register_expression_parser(parse_extension,            T___extension__, 25);
8454         register_expression_parser(parse_builtin_classify_type,
8455                                                      T___builtin_classify_type, 25);
8456 }
8457
8458 /**
8459  * Parse a asm statement arguments specification.
8460  */
8461 static asm_argument_t *parse_asm_arguments(bool is_out)
8462 {
8463         asm_argument_t *result = NULL;
8464         asm_argument_t *last   = NULL;
8465
8466         while (token.type == T_STRING_LITERAL || token.type == '[') {
8467                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
8468                 memset(argument, 0, sizeof(argument[0]));
8469
8470                 if (token.type == '[') {
8471                         eat('[');
8472                         if (token.type != T_IDENTIFIER) {
8473                                 parse_error_expected("while parsing asm argument",
8474                                                      T_IDENTIFIER, NULL);
8475                                 return NULL;
8476                         }
8477                         argument->symbol = token.v.symbol;
8478
8479                         expect(']');
8480                 }
8481
8482                 argument->constraints = parse_string_literals();
8483                 expect('(');
8484                 add_anchor_token(')');
8485                 expression_t *expression = parse_expression();
8486                 rem_anchor_token(')');
8487                 if (is_out) {
8488                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
8489                          * change size or type representation (e.g. int -> long is ok, but
8490                          * int -> float is not) */
8491                         if (expression->kind == EXPR_UNARY_CAST) {
8492                                 type_t      *const type = expression->base.type;
8493                                 type_kind_t  const kind = type->kind;
8494                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
8495                                         unsigned flags;
8496                                         unsigned size;
8497                                         if (kind == TYPE_ATOMIC) {
8498                                                 atomic_type_kind_t const akind = type->atomic.akind;
8499                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8500                                                 size  = get_atomic_type_size(akind);
8501                                         } else {
8502                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8503                                                 size  = get_atomic_type_size(get_intptr_kind());
8504                                         }
8505
8506                                         do {
8507                                                 expression_t *const value      = expression->unary.value;
8508                                                 type_t       *const value_type = value->base.type;
8509                                                 type_kind_t   const value_kind = value_type->kind;
8510
8511                                                 unsigned value_flags;
8512                                                 unsigned value_size;
8513                                                 if (value_kind == TYPE_ATOMIC) {
8514                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
8515                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
8516                                                         value_size  = get_atomic_type_size(value_akind);
8517                                                 } else if (value_kind == TYPE_POINTER) {
8518                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
8519                                                         value_size  = get_atomic_type_size(get_intptr_kind());
8520                                                 } else {
8521                                                         break;
8522                                                 }
8523
8524                                                 if (value_flags != flags || value_size != size)
8525                                                         break;
8526
8527                                                 expression = value;
8528                                         } while (expression->kind == EXPR_UNARY_CAST);
8529                                 }
8530                         }
8531
8532                         if (!is_lvalue(expression)) {
8533                                 errorf(&expression->base.source_position,
8534                                        "asm output argument is not an lvalue");
8535                         }
8536                 }
8537                 argument->expression = expression;
8538                 expect(')');
8539
8540                 set_address_taken(expression, true);
8541
8542                 if (last != NULL) {
8543                         last->next = argument;
8544                 } else {
8545                         result = argument;
8546                 }
8547                 last = argument;
8548
8549                 if (token.type != ',')
8550                         break;
8551                 eat(',');
8552         }
8553
8554         return result;
8555 end_error:
8556         return NULL;
8557 }
8558
8559 /**
8560  * Parse a asm statement clobber specification.
8561  */
8562 static asm_clobber_t *parse_asm_clobbers(void)
8563 {
8564         asm_clobber_t *result = NULL;
8565         asm_clobber_t *last   = NULL;
8566
8567         while(token.type == T_STRING_LITERAL) {
8568                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
8569                 clobber->clobber       = parse_string_literals();
8570
8571                 if (last != NULL) {
8572                         last->next = clobber;
8573                 } else {
8574                         result = clobber;
8575                 }
8576                 last = clobber;
8577
8578                 if (token.type != ',')
8579                         break;
8580                 eat(',');
8581         }
8582
8583         return result;
8584 }
8585
8586 /**
8587  * Parse an asm statement.
8588  */
8589 static statement_t *parse_asm_statement(void)
8590 {
8591         eat(T_asm);
8592
8593         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
8594         statement->base.source_position = token.source_position;
8595
8596         asm_statement_t *asm_statement = &statement->asms;
8597
8598         if (token.type == T_volatile) {
8599                 next_token();
8600                 asm_statement->is_volatile = true;
8601         }
8602
8603         expect('(');
8604         add_anchor_token(')');
8605         add_anchor_token(':');
8606         asm_statement->asm_text = parse_string_literals();
8607
8608         if (token.type != ':') {
8609                 rem_anchor_token(':');
8610                 goto end_of_asm;
8611         }
8612         eat(':');
8613
8614         asm_statement->outputs = parse_asm_arguments(true);
8615         if (token.type != ':') {
8616                 rem_anchor_token(':');
8617                 goto end_of_asm;
8618         }
8619         eat(':');
8620
8621         asm_statement->inputs = parse_asm_arguments(false);
8622         if (token.type != ':') {
8623                 rem_anchor_token(':');
8624                 goto end_of_asm;
8625         }
8626         rem_anchor_token(':');
8627         eat(':');
8628
8629         asm_statement->clobbers = parse_asm_clobbers();
8630
8631 end_of_asm:
8632         rem_anchor_token(')');
8633         expect(')');
8634         expect(';');
8635
8636         if (asm_statement->outputs == NULL) {
8637                 /* GCC: An 'asm' instruction without any output operands will be treated
8638                  * identically to a volatile 'asm' instruction. */
8639                 asm_statement->is_volatile = true;
8640         }
8641
8642         return statement;
8643 end_error:
8644         return create_invalid_statement();
8645 }
8646
8647 /**
8648  * Parse a case statement.
8649  */
8650 static statement_t *parse_case_statement(void)
8651 {
8652         eat(T_case);
8653
8654         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8655         source_position_t *const pos       = &statement->base.source_position;
8656
8657         *pos                             = token.source_position;
8658         expression_t *const expression   = parse_expression();
8659         statement->case_label.expression = expression;
8660         if (!is_constant_expression(expression)) {
8661                 /* This check does not prevent the error message in all cases of an
8662                  * prior error while parsing the expression.  At least it catches the
8663                  * common case of a mistyped enum entry. */
8664                 if (is_type_valid(expression->base.type)) {
8665                         errorf(pos, "case label does not reduce to an integer constant");
8666                 }
8667                 statement->case_label.is_bad = true;
8668         } else {
8669                 long const val = fold_constant(expression);
8670                 statement->case_label.first_case = val;
8671                 statement->case_label.last_case  = val;
8672         }
8673
8674         if (c_mode & _GNUC) {
8675                 if (token.type == T_DOTDOTDOT) {
8676                         next_token();
8677                         expression_t *const end_range   = parse_expression();
8678                         statement->case_label.end_range = end_range;
8679                         if (!is_constant_expression(end_range)) {
8680                                 /* This check does not prevent the error message in all cases of an
8681                                  * prior error while parsing the expression.  At least it catches the
8682                                  * common case of a mistyped enum entry. */
8683                                 if (is_type_valid(end_range->base.type)) {
8684                                         errorf(pos, "case range does not reduce to an integer constant");
8685                                 }
8686                                 statement->case_label.is_bad = true;
8687                         } else {
8688                                 long const val = fold_constant(end_range);
8689                                 statement->case_label.last_case = val;
8690
8691                                 if (val < statement->case_label.first_case) {
8692                                         statement->case_label.is_empty_range = true;
8693                                         warningf(pos, "empty range specified");
8694                                 }
8695                         }
8696                 }
8697         }
8698
8699         PUSH_PARENT(statement);
8700
8701         expect(':');
8702
8703         if (current_switch != NULL) {
8704                 if (! statement->case_label.is_bad) {
8705                         /* Check for duplicate case values */
8706                         case_label_statement_t *c = &statement->case_label;
8707                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
8708                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
8709                                         continue;
8710
8711                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
8712                                         continue;
8713
8714                                 errorf(pos, "duplicate case value (previously used %P)",
8715                                        &l->base.source_position);
8716                                 break;
8717                         }
8718                 }
8719                 /* link all cases into the switch statement */
8720                 if (current_switch->last_case == NULL) {
8721                         current_switch->first_case      = &statement->case_label;
8722                 } else {
8723                         current_switch->last_case->next = &statement->case_label;
8724                 }
8725                 current_switch->last_case = &statement->case_label;
8726         } else {
8727                 errorf(pos, "case label not within a switch statement");
8728         }
8729
8730         statement_t *const inner_stmt = parse_statement();
8731         statement->case_label.statement = inner_stmt;
8732         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8733                 errorf(&inner_stmt->base.source_position, "declaration after case label");
8734         }
8735
8736         POP_PARENT;
8737         return statement;
8738 end_error:
8739         POP_PARENT;
8740         return create_invalid_statement();
8741 }
8742
8743 /**
8744  * Parse a default statement.
8745  */
8746 static statement_t *parse_default_statement(void)
8747 {
8748         eat(T_default);
8749
8750         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
8751         statement->base.source_position = token.source_position;
8752
8753         PUSH_PARENT(statement);
8754
8755         expect(':');
8756         if (current_switch != NULL) {
8757                 const case_label_statement_t *def_label = current_switch->default_label;
8758                 if (def_label != NULL) {
8759                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
8760                                &def_label->base.source_position);
8761                 } else {
8762                         current_switch->default_label = &statement->case_label;
8763
8764                         /* link all cases into the switch statement */
8765                         if (current_switch->last_case == NULL) {
8766                                 current_switch->first_case      = &statement->case_label;
8767                         } else {
8768                                 current_switch->last_case->next = &statement->case_label;
8769                         }
8770                         current_switch->last_case = &statement->case_label;
8771                 }
8772         } else {
8773                 errorf(&statement->base.source_position,
8774                         "'default' label not within a switch statement");
8775         }
8776
8777         statement_t *const inner_stmt = parse_statement();
8778         statement->case_label.statement = inner_stmt;
8779         if (inner_stmt->kind == STATEMENT_DECLARATION) {
8780                 errorf(&inner_stmt->base.source_position, "declaration after default label");
8781         }
8782
8783         POP_PARENT;
8784         return statement;
8785 end_error:
8786         POP_PARENT;
8787         return create_invalid_statement();
8788 }
8789
8790 /**
8791  * Parse a label statement.
8792  */
8793 static statement_t *parse_label_statement(void)
8794 {
8795         assert(token.type == T_IDENTIFIER);
8796         symbol_t *symbol = token.v.symbol;
8797         next_token();
8798
8799         declaration_t *label = get_label(symbol);
8800
8801         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
8802         statement->base.source_position = token.source_position;
8803         statement->label.label          = label;
8804
8805         PUSH_PARENT(statement);
8806
8807         /* if statement is already set then the label is defined twice,
8808          * otherwise it was just mentioned in a goto/local label declaration so far */
8809         if (label->init.statement != NULL) {
8810                 errorf(HERE, "duplicate label '%Y' (declared %P)",
8811                        symbol, &label->source_position);
8812         } else {
8813                 label->source_position = token.source_position;
8814                 label->init.statement  = statement;
8815         }
8816
8817         eat(':');
8818
8819         if (token.type == '}') {
8820                 /* TODO only warn? */
8821                 if (false) {
8822                         warningf(HERE, "label at end of compound statement");
8823                         statement->label.statement = create_empty_statement();
8824                 } else {
8825                         errorf(HERE, "label at end of compound statement");
8826                         statement->label.statement = create_invalid_statement();
8827                 }
8828         } else if (token.type == ';') {
8829                 /* Eat an empty statement here, to avoid the warning about an empty
8830                  * statement after a label.  label:; is commonly used to have a label
8831                  * before a closing brace. */
8832                 statement->label.statement = create_empty_statement();
8833                 next_token();
8834         } else {
8835                 statement_t *const inner_stmt = parse_statement();
8836                 statement->label.statement = inner_stmt;
8837                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
8838                         errorf(&inner_stmt->base.source_position, "declaration after label");
8839                 }
8840         }
8841
8842         /* remember the labels in a list for later checking */
8843         if (label_last == NULL) {
8844                 label_first = &statement->label;
8845         } else {
8846                 label_last->next = &statement->label;
8847         }
8848         label_last = &statement->label;
8849
8850         POP_PARENT;
8851         return statement;
8852 }
8853
8854 /**
8855  * Parse an if statement.
8856  */
8857 static statement_t *parse_if(void)
8858 {
8859         eat(T_if);
8860
8861         statement_t *statement          = allocate_statement_zero(STATEMENT_IF);
8862         statement->base.source_position = token.source_position;
8863
8864         PUSH_PARENT(statement);
8865
8866         expect('(');
8867         add_anchor_token(')');
8868         statement->ifs.condition = parse_expression();
8869         rem_anchor_token(')');
8870         expect(')');
8871
8872         add_anchor_token(T_else);
8873         statement->ifs.true_statement = parse_statement();
8874         rem_anchor_token(T_else);
8875
8876         if (token.type == T_else) {
8877                 next_token();
8878                 statement->ifs.false_statement = parse_statement();
8879         }
8880
8881         POP_PARENT;
8882         return statement;
8883 end_error:
8884         POP_PARENT;
8885         return create_invalid_statement();
8886 }
8887
8888 /**
8889  * Check that all enums are handled in a switch.
8890  *
8891  * @param statement  the switch statement to check
8892  */
8893 static void check_enum_cases(const switch_statement_t *statement) {
8894         const type_t *type = skip_typeref(statement->expression->base.type);
8895         if (! is_type_enum(type))
8896                 return;
8897         const enum_type_t *enumt = &type->enumt;
8898
8899         /* if we have a default, no warnings */
8900         if (statement->default_label != NULL)
8901                 return;
8902
8903         /* FIXME: calculation of value should be done while parsing */
8904         const declaration_t *declaration;
8905         long last_value = -1;
8906         for (declaration = enumt->declaration->next;
8907              declaration != NULL && declaration->storage_class == STORAGE_CLASS_ENUM_ENTRY;
8908                  declaration = declaration->next) {
8909                 const expression_t *expression = declaration->init.enum_value;
8910                 long                value      = expression != NULL ? fold_constant(expression) : last_value + 1;
8911                 bool                found      = false;
8912                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
8913                         if (l->expression == NULL)
8914                                 continue;
8915                         if (l->first_case <= value && value <= l->last_case) {
8916                                 found = true;
8917                                 break;
8918                         }
8919                 }
8920                 if (! found) {
8921                         warningf(&statement->base.source_position,
8922                                 "enumeration value '%Y' not handled in switch", declaration->symbol);
8923                 }
8924                 last_value = value;
8925         }
8926 }
8927
8928 /**
8929  * Parse a switch statement.
8930  */
8931 static statement_t *parse_switch(void)
8932 {
8933         eat(T_switch);
8934
8935         statement_t *statement          = allocate_statement_zero(STATEMENT_SWITCH);
8936         statement->base.source_position = token.source_position;
8937
8938         PUSH_PARENT(statement);
8939
8940         expect('(');
8941         add_anchor_token(')');
8942         expression_t *const expr = parse_expression();
8943         type_t       *      type = skip_typeref(expr->base.type);
8944         if (is_type_integer(type)) {
8945                 type = promote_integer(type);
8946                 if (warning.traditional) {
8947                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
8948                                 warningf(&expr->base.source_position,
8949                                         "'%T' switch expression not converted to '%T' in ISO C",
8950                                         type, type_int);
8951                         }
8952                 }
8953         } else if (is_type_valid(type)) {
8954                 errorf(&expr->base.source_position,
8955                        "switch quantity is not an integer, but '%T'", type);
8956                 type = type_error_type;
8957         }
8958         statement->switchs.expression = create_implicit_cast(expr, type);
8959         expect(')');
8960         rem_anchor_token(')');
8961
8962         switch_statement_t *rem = current_switch;
8963         current_switch          = &statement->switchs;
8964         statement->switchs.body = parse_statement();
8965         current_switch          = rem;
8966
8967         if (warning.switch_default &&
8968             statement->switchs.default_label == NULL) {
8969                 warningf(&statement->base.source_position, "switch has no default case");
8970         }
8971         if (warning.switch_enum)
8972                 check_enum_cases(&statement->switchs);
8973
8974         POP_PARENT;
8975         return statement;
8976 end_error:
8977         POP_PARENT;
8978         return create_invalid_statement();
8979 }
8980
8981 static statement_t *parse_loop_body(statement_t *const loop)
8982 {
8983         statement_t *const rem = current_loop;
8984         current_loop = loop;
8985
8986         statement_t *const body = parse_statement();
8987
8988         current_loop = rem;
8989         return body;
8990 }
8991
8992 /**
8993  * Parse a while statement.
8994  */
8995 static statement_t *parse_while(void)
8996 {
8997         eat(T_while);
8998
8999         statement_t *statement          = allocate_statement_zero(STATEMENT_WHILE);
9000         statement->base.source_position = token.source_position;
9001
9002         PUSH_PARENT(statement);
9003
9004         expect('(');
9005         add_anchor_token(')');
9006         statement->whiles.condition = parse_expression();
9007         rem_anchor_token(')');
9008         expect(')');
9009
9010         statement->whiles.body = parse_loop_body(statement);
9011
9012         POP_PARENT;
9013         return statement;
9014 end_error:
9015         POP_PARENT;
9016         return create_invalid_statement();
9017 }
9018
9019 /**
9020  * Parse a do statement.
9021  */
9022 static statement_t *parse_do(void)
9023 {
9024         eat(T_do);
9025
9026         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
9027         statement->base.source_position = token.source_position;
9028
9029         PUSH_PARENT(statement)
9030
9031         add_anchor_token(T_while);
9032         statement->do_while.body = parse_loop_body(statement);
9033         rem_anchor_token(T_while);
9034
9035         expect(T_while);
9036         expect('(');
9037         add_anchor_token(')');
9038         statement->do_while.condition = parse_expression();
9039         rem_anchor_token(')');
9040         expect(')');
9041         expect(';');
9042
9043         POP_PARENT;
9044         return statement;
9045 end_error:
9046         POP_PARENT;
9047         return create_invalid_statement();
9048 }
9049
9050 /**
9051  * Parse a for statement.
9052  */
9053 static statement_t *parse_for(void)
9054 {
9055         eat(T_for);
9056
9057         statement_t *statement          = allocate_statement_zero(STATEMENT_FOR);
9058         statement->base.source_position = token.source_position;
9059
9060         PUSH_PARENT(statement);
9061
9062         int      top        = environment_top();
9063         scope_t *last_scope = scope;
9064         set_scope(&statement->fors.scope);
9065
9066         expect('(');
9067         add_anchor_token(')');
9068
9069         if (token.type != ';') {
9070                 if (is_declaration_specifier(&token, false)) {
9071                         parse_declaration(record_declaration);
9072                 } else {
9073                         add_anchor_token(';');
9074                         expression_t *const init = parse_expression();
9075                         statement->fors.initialisation = init;
9076                         if (warning.unused_value && !expression_has_effect(init)) {
9077                                 warningf(&init->base.source_position,
9078                                          "initialisation of 'for'-statement has no effect");
9079                         }
9080                         rem_anchor_token(';');
9081                         expect(';');
9082                 }
9083         } else {
9084                 expect(';');
9085         }
9086
9087         if (token.type != ';') {
9088                 add_anchor_token(';');
9089                 statement->fors.condition = parse_expression();
9090                 rem_anchor_token(';');
9091         }
9092         expect(';');
9093         if (token.type != ')') {
9094                 expression_t *const step = parse_expression();
9095                 statement->fors.step = step;
9096                 if (warning.unused_value && !expression_has_effect(step)) {
9097                         warningf(&step->base.source_position,
9098                                  "step of 'for'-statement has no effect");
9099                 }
9100         }
9101         rem_anchor_token(')');
9102         expect(')');
9103         statement->fors.body = parse_loop_body(statement);
9104
9105         assert(scope == &statement->fors.scope);
9106         set_scope(last_scope);
9107         environment_pop_to(top);
9108
9109         POP_PARENT;
9110         return statement;
9111
9112 end_error:
9113         POP_PARENT;
9114         rem_anchor_token(')');
9115         assert(scope == &statement->fors.scope);
9116         set_scope(last_scope);
9117         environment_pop_to(top);
9118
9119         return create_invalid_statement();
9120 }
9121
9122 /**
9123  * Parse a goto statement.
9124  */
9125 static statement_t *parse_goto(void)
9126 {
9127         source_position_t source_position = token.source_position;
9128         eat(T_goto);
9129
9130         statement_t *statement;
9131         if (c_mode & _GNUC && token.type == '*') {
9132                 next_token();
9133                 expression_t *expression = parse_expression();
9134
9135                 /* Argh: although documentation say the expression must be of type void *,
9136                  * gcc excepts anything that can be casted into void * without error */
9137                 type_t *type = expression->base.type;
9138
9139                 if (type != type_error_type) {
9140                         if (!is_type_pointer(type) && !is_type_integer(type)) {
9141                                 errorf(&source_position, "cannot convert to a pointer type");
9142                         } else if (type != type_void_ptr) {
9143                                 warningf(&source_position,
9144                                         "type of computed goto expression should be 'void*' not '%T'", type);
9145                         }
9146                         expression = create_implicit_cast(expression, type_void_ptr);
9147                 }
9148
9149                 statement                       = allocate_statement_zero(STATEMENT_GOTO);
9150                 statement->base.source_position = source_position;
9151                 statement->gotos.expression     = expression;
9152         } else {
9153                 if (token.type != T_IDENTIFIER) {
9154                         if (c_mode & _GNUC)
9155                                 parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
9156                         else
9157                                 parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
9158                         eat_statement();
9159                         goto end_error;
9160                 }
9161                 symbol_t *symbol = token.v.symbol;
9162                 next_token();
9163
9164                 statement                       = allocate_statement_zero(STATEMENT_GOTO);
9165                 statement->base.source_position = source_position;
9166                 statement->gotos.label          = get_label(symbol);
9167         }
9168
9169         /* remember the goto's in a list for later checking */
9170         if (goto_last == NULL) {
9171                 goto_first = &statement->gotos;
9172         } else {
9173                 goto_last->next = &statement->gotos;
9174         }
9175         goto_last = &statement->gotos;
9176
9177         expect(';');
9178
9179         return statement;
9180 end_error:
9181         return create_invalid_statement();
9182 }
9183
9184 /**
9185  * Parse a continue statement.
9186  */
9187 static statement_t *parse_continue(void)
9188 {
9189         if (current_loop == NULL) {
9190                 errorf(HERE, "continue statement not within loop");
9191         }
9192
9193         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
9194         statement->base.source_position = token.source_position;
9195
9196         eat(T_continue);
9197         expect(';');
9198
9199 end_error:
9200         return statement;
9201 }
9202
9203 /**
9204  * Parse a break statement.
9205  */
9206 static statement_t *parse_break(void)
9207 {
9208         if (current_switch == NULL && current_loop == NULL) {
9209                 errorf(HERE, "break statement not within loop or switch");
9210         }
9211
9212         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
9213         statement->base.source_position = token.source_position;
9214
9215         eat(T_break);
9216         expect(';');
9217
9218 end_error:
9219         return statement;
9220 }
9221
9222 /**
9223  * Parse a __leave statement.
9224  */
9225 static statement_t *parse_leave_statement(void)
9226 {
9227         if (current_try == NULL) {
9228                 errorf(HERE, "__leave statement not within __try");
9229         }
9230
9231         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
9232         statement->base.source_position = token.source_position;
9233
9234         eat(T___leave);
9235         expect(';');
9236
9237 end_error:
9238         return statement;
9239 }
9240
9241 /**
9242  * Check if a given declaration represents a local variable.
9243  */
9244 static bool is_local_var_declaration(const declaration_t *declaration)
9245 {
9246         switch ((storage_class_tag_t) declaration->storage_class) {
9247         case STORAGE_CLASS_AUTO:
9248         case STORAGE_CLASS_REGISTER: {
9249                 const type_t *type = skip_typeref(declaration->type);
9250                 if (is_type_function(type)) {
9251                         return false;
9252                 } else {
9253                         return true;
9254                 }
9255         }
9256         default:
9257                 return false;
9258         }
9259 }
9260
9261 /**
9262  * Check if a given declaration represents a variable.
9263  */
9264 static bool is_var_declaration(const declaration_t *declaration)
9265 {
9266         if (declaration->storage_class == STORAGE_CLASS_TYPEDEF)
9267                 return false;
9268
9269         const type_t *type = skip_typeref(declaration->type);
9270         return !is_type_function(type);
9271 }
9272
9273 /**
9274  * Check if a given expression represents a local variable.
9275  */
9276 static bool is_local_variable(const expression_t *expression)
9277 {
9278         if (expression->base.kind != EXPR_REFERENCE) {
9279                 return false;
9280         }
9281         const declaration_t *declaration = expression->reference.declaration;
9282         return is_local_var_declaration(declaration);
9283 }
9284
9285 /**
9286  * Check if a given expression represents a local variable and
9287  * return its declaration then, else return NULL.
9288  */
9289 declaration_t *expr_is_variable(const expression_t *expression)
9290 {
9291         if (expression->base.kind != EXPR_REFERENCE) {
9292                 return NULL;
9293         }
9294         declaration_t *declaration = expression->reference.declaration;
9295         if (is_var_declaration(declaration))
9296                 return declaration;
9297         return NULL;
9298 }
9299
9300 /**
9301  * Parse a return statement.
9302  */
9303 static statement_t *parse_return(void)
9304 {
9305         statement_t *statement          = allocate_statement_zero(STATEMENT_RETURN);
9306         statement->base.source_position = token.source_position;
9307
9308         eat(T_return);
9309
9310         expression_t *return_value = NULL;
9311         if (token.type != ';') {
9312                 return_value = parse_expression();
9313         }
9314
9315         const type_t *const func_type = current_function->type;
9316         assert(is_type_function(func_type));
9317         type_t *const return_type = skip_typeref(func_type->function.return_type);
9318
9319         if (return_value != NULL) {
9320                 type_t *return_value_type = skip_typeref(return_value->base.type);
9321
9322                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)
9323                                 && !is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
9324                         warningf(&statement->base.source_position,
9325                                  "'return' with a value, in function returning void");
9326                         return_value = NULL;
9327                 } else {
9328                         assign_error_t error = semantic_assign(return_type, return_value);
9329                         report_assign_error(error, return_type, return_value, "'return'",
9330                                             &statement->base.source_position);
9331                         return_value = create_implicit_cast(return_value, return_type);
9332                 }
9333                 /* check for returning address of a local var */
9334                 if (return_value != NULL &&
9335                                 return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
9336                         const expression_t *expression = return_value->unary.value;
9337                         if (is_local_variable(expression)) {
9338                                 warningf(&statement->base.source_position,
9339                                          "function returns address of local variable");
9340                         }
9341                 }
9342         } else {
9343                 if (!is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
9344                         warningf(&statement->base.source_position,
9345                                  "'return' without value, in function returning non-void");
9346                 }
9347         }
9348         statement->returns.value = return_value;
9349
9350         expect(';');
9351
9352 end_error:
9353         return statement;
9354 }
9355
9356 /**
9357  * Parse a declaration statement.
9358  */
9359 static statement_t *parse_declaration_statement(void)
9360 {
9361         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9362
9363         statement->base.source_position = token.source_position;
9364
9365         declaration_t *before = last_declaration;
9366         parse_declaration(record_declaration);
9367
9368         if (before == NULL) {
9369                 statement->declaration.declarations_begin = scope->declarations;
9370         } else {
9371                 statement->declaration.declarations_begin = before->next;
9372         }
9373         statement->declaration.declarations_end = last_declaration;
9374
9375         return statement;
9376 }
9377
9378 /**
9379  * Parse an expression statement, ie. expr ';'.
9380  */
9381 static statement_t *parse_expression_statement(void)
9382 {
9383         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
9384
9385         statement->base.source_position  = token.source_position;
9386         expression_t *const expr         = parse_expression();
9387         statement->expression.expression = expr;
9388
9389         expect(';');
9390
9391 end_error:
9392         return statement;
9393 }
9394
9395 /**
9396  * Parse a microsoft __try { } __finally { } or
9397  * __try{ } __except() { }
9398  */
9399 static statement_t *parse_ms_try_statment(void)
9400 {
9401         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
9402         statement->base.source_position  = token.source_position;
9403         eat(T___try);
9404
9405         PUSH_PARENT(statement);
9406
9407         ms_try_statement_t *rem = current_try;
9408         current_try = &statement->ms_try;
9409         statement->ms_try.try_statement = parse_compound_statement(false);
9410         current_try = rem;
9411
9412         POP_PARENT;
9413
9414         if (token.type == T___except) {
9415                 eat(T___except);
9416                 expect('(');
9417                 add_anchor_token(')');
9418                 expression_t *const expr = parse_expression();
9419                 type_t       *      type = skip_typeref(expr->base.type);
9420                 if (is_type_integer(type)) {
9421                         type = promote_integer(type);
9422                 } else if (is_type_valid(type)) {
9423                         errorf(&expr->base.source_position,
9424                                "__expect expression is not an integer, but '%T'", type);
9425                         type = type_error_type;
9426                 }
9427                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
9428                 rem_anchor_token(')');
9429                 expect(')');
9430                 statement->ms_try.final_statement = parse_compound_statement(false);
9431         } else if (token.type == T__finally) {
9432                 eat(T___finally);
9433                 statement->ms_try.final_statement = parse_compound_statement(false);
9434         } else {
9435                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
9436                 return create_invalid_statement();
9437         }
9438         return statement;
9439 end_error:
9440         return create_invalid_statement();
9441 }
9442
9443 static statement_t *parse_empty_statement(void)
9444 {
9445         if (warning.empty_statement) {
9446                 warningf(HERE, "statement is empty");
9447         }
9448         statement_t *const statement = create_empty_statement();
9449         eat(';');
9450         return statement;
9451 }
9452
9453 static statement_t *parse_local_label_declaration(void) {
9454         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9455         statement->base.source_position = token.source_position;
9456
9457         eat(T___label__);
9458
9459         declaration_t *begin = NULL, *end = NULL;
9460
9461         while (true) {
9462                 if (token.type != T_IDENTIFIER) {
9463                         parse_error_expected("while parsing local label declaration",
9464                                 T_IDENTIFIER, NULL);
9465                         goto end_error;
9466                 }
9467                 symbol_t      *symbol      = token.v.symbol;
9468                 declaration_t *declaration = get_declaration(symbol, NAMESPACE_LOCAL_LABEL);
9469                 if (declaration != NULL) {
9470                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition at %P)",
9471                                 symbol, &declaration->source_position);
9472                 } else {
9473                         declaration = allocate_declaration_zero();
9474                         declaration->namespc         = NAMESPACE_LOCAL_LABEL;
9475                         declaration->source_position = token.source_position;
9476                         declaration->symbol          = symbol;
9477                         declaration->parent_scope    = scope;
9478                         declaration->init.statement  = NULL;
9479
9480                         if (end != NULL)
9481                                 end->next = declaration;
9482                         end = declaration;
9483                         if (begin == NULL)
9484                                 begin = declaration;
9485
9486                         local_label_push(declaration);
9487                 }
9488                 next_token();
9489
9490                 if (token.type != ',')
9491                         break;
9492                 next_token();
9493         }
9494         eat(';');
9495 end_error:
9496         statement->declaration.declarations_begin = begin;
9497         statement->declaration.declarations_end   = end;
9498         return statement;
9499 }
9500
9501 /**
9502  * Parse a statement.
9503  * There's also parse_statement() which additionally checks for
9504  * "statement has no effect" warnings
9505  */
9506 static statement_t *intern_parse_statement(void)
9507 {
9508         statement_t *statement = NULL;
9509
9510         /* declaration or statement */
9511         add_anchor_token(';');
9512         switch (token.type) {
9513         case T_IDENTIFIER: {
9514                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
9515                 if (la1_type == ':') {
9516                         statement = parse_label_statement();
9517                 } else if (is_typedef_symbol(token.v.symbol)) {
9518                         statement = parse_declaration_statement();
9519                 } else switch (la1_type) {
9520                         case '*':
9521                                 if (get_declaration(token.v.symbol, NAMESPACE_NORMAL) != NULL)
9522                                         goto expression_statment;
9523                                 /* FALLTHROUGH */
9524
9525                         DECLARATION_START
9526                         case T_IDENTIFIER:
9527                                 statement = parse_declaration_statement();
9528                                 break;
9529
9530                         default:
9531 expression_statment:
9532                                 statement = parse_expression_statement();
9533                                 break;
9534                 }
9535                 break;
9536         }
9537
9538         case T___extension__:
9539                 /* This can be a prefix to a declaration or an expression statement.
9540                  * We simply eat it now and parse the rest with tail recursion. */
9541                 do {
9542                         next_token();
9543                 } while (token.type == T___extension__);
9544                 statement = parse_statement();
9545                 break;
9546
9547         DECLARATION_START
9548                 statement = parse_declaration_statement();
9549                 break;
9550
9551         case T___label__:
9552                 statement = parse_local_label_declaration();
9553                 break;
9554
9555         case ';':        statement = parse_empty_statement();         break;
9556         case '{':        statement = parse_compound_statement(false); break;
9557         case T___leave:  statement = parse_leave_statement();         break;
9558         case T___try:    statement = parse_ms_try_statment();         break;
9559         case T_asm:      statement = parse_asm_statement();           break;
9560         case T_break:    statement = parse_break();                   break;
9561         case T_case:     statement = parse_case_statement();          break;
9562         case T_continue: statement = parse_continue();                break;
9563         case T_default:  statement = parse_default_statement();       break;
9564         case T_do:       statement = parse_do();                      break;
9565         case T_for:      statement = parse_for();                     break;
9566         case T_goto:     statement = parse_goto();                    break;
9567         case T_if:       statement = parse_if ();                     break;
9568         case T_return:   statement = parse_return();                  break;
9569         case T_switch:   statement = parse_switch();                  break;
9570         case T_while:    statement = parse_while();                   break;
9571
9572         case '!':
9573         case '&':
9574         case '(':
9575         case '*':
9576         case '+':
9577         case '-':
9578         case '~':
9579         case T_ANDAND:
9580         case T_CHARACTER_CONSTANT:
9581         case T_FLOATINGPOINT:
9582         case T_INTEGER:
9583         case T_MINUSMINUS:
9584         case T_PLUSPLUS:
9585         case T_STRING_LITERAL:
9586         case T_WIDE_CHARACTER_CONSTANT:
9587         case T_WIDE_STRING_LITERAL:
9588         case T___FUNCDNAME__:
9589         case T___FUNCSIG__:
9590         case T___FUNCTION__:
9591         case T___PRETTY_FUNCTION__:
9592         case T___builtin_alloca:
9593         case T___builtin_classify_type:
9594         case T___builtin_constant_p:
9595         case T___builtin_expect:
9596         case T___builtin_huge_val:
9597         case T___builtin_isgreater:
9598         case T___builtin_isgreaterequal:
9599         case T___builtin_isless:
9600         case T___builtin_islessequal:
9601         case T___builtin_islessgreater:
9602         case T___builtin_isunordered:
9603         case T___builtin_nan:
9604         case T___builtin_nand:
9605         case T___builtin_nanf:
9606         case T___builtin_offsetof:
9607         case T___builtin_prefetch:
9608         case T___builtin_va_arg:
9609         case T___builtin_va_end:
9610         case T___builtin_va_start:
9611         case T___func__:
9612         case T___noop:
9613         case T__assume:
9614                 statement = parse_expression_statement();
9615                 break;
9616
9617         default:
9618                 errorf(HERE, "unexpected token %K while parsing statement", &token);
9619                 statement = create_invalid_statement();
9620                 if (!at_anchor())
9621                         next_token();
9622                 break;
9623         }
9624         rem_anchor_token(';');
9625
9626         assert(statement != NULL
9627                         && statement->base.source_position.input_name != NULL);
9628
9629         return statement;
9630 }
9631
9632 /**
9633  * parse a statement and emits "statement has no effect" warning if needed
9634  * (This is really a wrapper around intern_parse_statement with check for 1
9635  *  single warning. It is needed, because for statement expressions we have
9636  *  to avoid the warning on the last statement)
9637  */
9638 static statement_t *parse_statement(void)
9639 {
9640         statement_t *statement = intern_parse_statement();
9641
9642         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
9643                 expression_t *expression = statement->expression.expression;
9644                 if (!expression_has_effect(expression)) {
9645                         warningf(&expression->base.source_position,
9646                                         "statement has no effect");
9647                 }
9648         }
9649
9650         return statement;
9651 }
9652
9653 /**
9654  * Parse a compound statement.
9655  */
9656 static statement_t *parse_compound_statement(bool inside_expression_statement)
9657 {
9658         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
9659         statement->base.source_position = token.source_position;
9660
9661         PUSH_PARENT(statement);
9662
9663         eat('{');
9664         add_anchor_token('}');
9665
9666         int      top        = environment_top();
9667         int      top_local  = local_label_top();
9668         scope_t *last_scope = scope;
9669         set_scope(&statement->compound.scope);
9670
9671         statement_t **anchor            = &statement->compound.statements;
9672         bool          only_decls_so_far = true;
9673         while (token.type != '}' && token.type != T_EOF) {
9674                 statement_t *sub_statement = intern_parse_statement();
9675                 if (is_invalid_statement(sub_statement)) {
9676                         /* an error occurred. if we are at an anchor, return */
9677                         if (at_anchor())
9678                                 goto end_error;
9679                         continue;
9680                 }
9681
9682                 if (warning.declaration_after_statement) {
9683                         if (sub_statement->kind != STATEMENT_DECLARATION) {
9684                                 only_decls_so_far = false;
9685                         } else if (!only_decls_so_far) {
9686                                 warningf(&sub_statement->base.source_position,
9687                                          "ISO C90 forbids mixed declarations and code");
9688                         }
9689                 }
9690
9691                 *anchor = sub_statement;
9692
9693                 while (sub_statement->base.next != NULL)
9694                         sub_statement = sub_statement->base.next;
9695
9696                 anchor = &sub_statement->base.next;
9697         }
9698
9699         if (token.type == '}') {
9700                 next_token();
9701         } else {
9702                 errorf(&statement->base.source_position,
9703                        "end of file while looking for closing '}'");
9704         }
9705
9706         /* look over all statements again to produce no effect warnings */
9707         if (warning.unused_value) {
9708                 statement_t *sub_statement = statement->compound.statements;
9709                 for( ; sub_statement != NULL; sub_statement = sub_statement->base.next) {
9710                         if (sub_statement->kind != STATEMENT_EXPRESSION)
9711                                 continue;
9712                         /* don't emit a warning for the last expression in an expression
9713                          * statement as it has always an effect */
9714                         if (inside_expression_statement && sub_statement->base.next == NULL)
9715                                 continue;
9716
9717                         expression_t *expression = sub_statement->expression.expression;
9718                         if (!expression_has_effect(expression)) {
9719                                 warningf(&expression->base.source_position,
9720                                          "statement has no effect");
9721                         }
9722                 }
9723         }
9724
9725 end_error:
9726         rem_anchor_token('}');
9727         assert(scope == &statement->compound.scope);
9728         set_scope(last_scope);
9729         environment_pop_to(top);
9730         local_label_pop_to(top_local);
9731
9732         POP_PARENT;
9733         return statement;
9734 }
9735
9736 /**
9737  * Initialize builtin types.
9738  */
9739 static void initialize_builtin_types(void)
9740 {
9741         type_intmax_t    = make_global_typedef("__intmax_t__",      type_long_long);
9742         type_size_t      = make_global_typedef("__SIZE_TYPE__",     type_unsigned_long);
9743         type_ssize_t     = make_global_typedef("__SSIZE_TYPE__",    type_long);
9744         type_ptrdiff_t   = make_global_typedef("__PTRDIFF_TYPE__",  type_long);
9745         type_uintmax_t   = make_global_typedef("__uintmax_t__",     type_unsigned_long_long);
9746         type_uptrdiff_t  = make_global_typedef("__UPTRDIFF_TYPE__", type_unsigned_long);
9747         type_wchar_t     = make_global_typedef("__WCHAR_TYPE__",    opt_short_wchar_t ? type_unsigned_short : type_int);
9748         type_wint_t      = make_global_typedef("__WINT_TYPE__",     type_int);
9749
9750         type_intmax_t_ptr  = make_pointer_type(type_intmax_t,  TYPE_QUALIFIER_NONE);
9751         type_ptrdiff_t_ptr = make_pointer_type(type_ptrdiff_t, TYPE_QUALIFIER_NONE);
9752         type_ssize_t_ptr   = make_pointer_type(type_ssize_t,   TYPE_QUALIFIER_NONE);
9753         type_wchar_t_ptr   = make_pointer_type(type_wchar_t,   TYPE_QUALIFIER_NONE);
9754
9755         /* const version of wchar_t */
9756         type_const_wchar_t = allocate_type_zero(TYPE_TYPEDEF, &builtin_source_position);
9757         type_const_wchar_t->typedeft.declaration  = type_wchar_t->typedeft.declaration;
9758         type_const_wchar_t->base.qualifiers      |= TYPE_QUALIFIER_CONST;
9759
9760         type_const_wchar_t_ptr = make_pointer_type(type_const_wchar_t, TYPE_QUALIFIER_NONE);
9761 }
9762
9763 /**
9764  * Check for unused global static functions and variables
9765  */
9766 static void check_unused_globals(void)
9767 {
9768         if (!warning.unused_function && !warning.unused_variable)
9769                 return;
9770
9771         for (const declaration_t *decl = global_scope->declarations; decl != NULL; decl = decl->next) {
9772                 if (decl->used                  ||
9773                     decl->modifiers & DM_UNUSED ||
9774                     decl->modifiers & DM_USED   ||
9775                     decl->storage_class != STORAGE_CLASS_STATIC)
9776                         continue;
9777
9778                 type_t *const type = decl->type;
9779                 const char *s;
9780                 if (is_type_function(skip_typeref(type))) {
9781                         if (!warning.unused_function || decl->is_inline)
9782                                 continue;
9783
9784                         s = (decl->init.statement != NULL ? "defined" : "declared");
9785                 } else {
9786                         if (!warning.unused_variable)
9787                                 continue;
9788
9789                         s = "defined";
9790                 }
9791
9792                 warningf(&decl->source_position, "'%#T' %s but not used",
9793                         type, decl->symbol, s);
9794         }
9795 }
9796
9797 static void parse_global_asm(void)
9798 {
9799         eat(T_asm);
9800         expect('(');
9801
9802         statement_t *statement          = allocate_statement_zero(STATEMENT_ASM);
9803         statement->base.source_position = token.source_position;
9804         statement->asms.asm_text        = parse_string_literals();
9805         statement->base.next            = unit->global_asm;
9806         unit->global_asm                = statement;
9807
9808         expect(')');
9809         expect(';');
9810
9811 end_error:;
9812 }
9813
9814 /**
9815  * Parse a translation unit.
9816  */
9817 static void parse_translation_unit(void)
9818 {
9819         for (;;) {
9820 #ifndef NDEBUG
9821                 bool anchor_leak = false;
9822                 for (token_type_t i = 0; i != T_LAST_TOKEN; ++i) {
9823                         unsigned char count = token_anchor_set[i];
9824                         if (count != 0) {
9825                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
9826                                 anchor_leak = true;
9827                         }
9828                 }
9829                 if (anchor_leak)
9830                         abort();
9831 #endif
9832
9833                 switch (token.type) {
9834                         DECLARATION_START
9835                         case T_IDENTIFIER:
9836                         case T___extension__:
9837                                 parse_external_declaration();
9838                                 break;
9839
9840                         case T_asm:
9841                                 parse_global_asm();
9842                                 break;
9843
9844                         case T_EOF:
9845                                 return;
9846
9847                         case ';':
9848                                 /* TODO error in strict mode */
9849                                 warningf(HERE, "stray ';' outside of function");
9850                                 next_token();
9851                                 break;
9852
9853                         default:
9854                                 errorf(HERE, "stray %K outside of function", &token);
9855                                 if (token.type == '(' || token.type == '{' || token.type == '[')
9856                                         eat_until_matching_token(token.type);
9857                                 next_token();
9858                                 break;
9859                 }
9860         }
9861 }
9862
9863 /**
9864  * Parse the input.
9865  *
9866  * @return  the translation unit or NULL if errors occurred.
9867  */
9868 void start_parsing(void)
9869 {
9870         environment_stack = NEW_ARR_F(stack_entry_t, 0);
9871         label_stack       = NEW_ARR_F(stack_entry_t, 0);
9872         local_label_stack = NEW_ARR_F(stack_entry_t, 0);
9873         diagnostic_count  = 0;
9874         error_count       = 0;
9875         warning_count     = 0;
9876
9877         type_set_output(stderr);
9878         ast_set_output(stderr);
9879
9880         assert(unit == NULL);
9881         unit = allocate_ast_zero(sizeof(unit[0]));
9882
9883         assert(global_scope == NULL);
9884         global_scope = &unit->scope;
9885
9886         assert(scope == NULL);
9887         set_scope(&unit->scope);
9888
9889         initialize_builtin_types();
9890 }
9891
9892 translation_unit_t *finish_parsing(void)
9893 {
9894         assert(scope == &unit->scope);
9895         scope          = NULL;
9896         last_declaration = NULL;
9897
9898         assert(global_scope == &unit->scope);
9899         check_unused_globals();
9900         global_scope = NULL;
9901
9902         DEL_ARR_F(environment_stack);
9903         DEL_ARR_F(label_stack);
9904         DEL_ARR_F(local_label_stack);
9905
9906         translation_unit_t *result = unit;
9907         unit = NULL;
9908         return result;
9909 }
9910
9911 void parse(void)
9912 {
9913         lookahead_bufpos = 0;
9914         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
9915                 next_token();
9916         }
9917         parse_translation_unit();
9918 }
9919
9920 /**
9921  * Initialize the parser.
9922  */
9923 void init_parser(void)
9924 {
9925         sym_anonymous = symbol_table_insert("<anonymous>");
9926
9927         if (c_mode & _MS) {
9928                 /* add predefined symbols for extended-decl-modifier */
9929                 sym_align      = symbol_table_insert("align");
9930                 sym_allocate   = symbol_table_insert("allocate");
9931                 sym_dllimport  = symbol_table_insert("dllimport");
9932                 sym_dllexport  = symbol_table_insert("dllexport");
9933                 sym_naked      = symbol_table_insert("naked");
9934                 sym_noinline   = symbol_table_insert("noinline");
9935                 sym_noreturn   = symbol_table_insert("noreturn");
9936                 sym_nothrow    = symbol_table_insert("nothrow");
9937                 sym_novtable   = symbol_table_insert("novtable");
9938                 sym_property   = symbol_table_insert("property");
9939                 sym_get        = symbol_table_insert("get");
9940                 sym_put        = symbol_table_insert("put");
9941                 sym_selectany  = symbol_table_insert("selectany");
9942                 sym_thread     = symbol_table_insert("thread");
9943                 sym_uuid       = symbol_table_insert("uuid");
9944                 sym_deprecated = symbol_table_insert("deprecated");
9945                 sym_restrict   = symbol_table_insert("restrict");
9946                 sym_noalias    = symbol_table_insert("noalias");
9947         }
9948         memset(token_anchor_set, 0, sizeof(token_anchor_set));
9949
9950         init_expression_parsers();
9951         obstack_init(&temp_obst);
9952
9953         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
9954         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
9955 }
9956
9957 /**
9958  * Terminate the parser.
9959  */
9960 void exit_parser(void)
9961 {
9962         obstack_free(&temp_obst, NULL);
9963 }