nsz Git - cparser/blob - parser.c

   1 /*
   2  * This file is part of cparser.
   3  * Copyright (C) 2007-2009 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 "entity_t.h"
  37 #include "attribute_t.h"
  38 #include "lang_features.h"
  39 #include "walk_statements.h"
  40 #include "warning.h"
  41 #include "printer.h"
  42 #include "adt/bitfiddle.h"
  43 #include "adt/error.h"
  44 #include "adt/array.h"
  45
  46 //#define PRINT_TOKENS
  47 #define MAX_LOOKAHEAD 1
  48
  49 typedef struct {
  50         entity_t           *old_entity;
  51         symbol_t           *symbol;
  52         entity_namespace_t  namespc;
  53 } stack_entry_t;
  54
  55 typedef struct declaration_specifiers_t  declaration_specifiers_t;
  56 struct declaration_specifiers_t {
  57         source_position_t  source_position;
  58         storage_class_t    storage_class;
  59         unsigned char      alignment;         /**< Alignment, 0 if not set. */
  60         bool               is_inline    : 1;
  61         bool               thread_local : 1;  /**< GCC __thread */
  62         attribute_t       *attributes;        /**< list of attributes */
  63         type_t            *type;
  64 };
  65
  66 /**
  67  * An environment for parsing initializers (and compound literals).
  68  */
  69 typedef struct parse_initializer_env_t {
  70         type_t     *type;   /**< the type of the initializer. In case of an
  71                                  array type with unspecified size this gets
  72                                  adjusted to the actual size. */
  73         entity_t   *entity; /**< the variable that is initialized if any */
  74         bool        must_be_constant;
  75 } parse_initializer_env_t;
  76
  77 typedef entity_t* (*parsed_declaration_func) (entity_t *declaration, bool is_definition);
  78
  79 /** The current token. */
  80 static token_t              token;
  81 /** The lookahead ring-buffer. */
  82 static token_t              lookahead_buffer[MAX_LOOKAHEAD];
  83 /** Position of the next token in the lookahead buffer. */
  84 static size_t               lookahead_bufpos;
  85 static stack_entry_t       *environment_stack = NULL;
  86 static stack_entry_t       *label_stack       = NULL;
  87 static scope_t             *file_scope        = NULL;
  88 static scope_t             *current_scope     = NULL;
  89 /** Point to the current function declaration if inside a function. */
  90 static function_t          *current_function  = NULL;
  91 static entity_t            *current_entity    = NULL;
  92 static entity_t            *current_init_decl = NULL;
  93 static switch_statement_t  *current_switch    = NULL;
  94 static statement_t         *current_loop      = NULL;
  95 static statement_t         *current_parent    = NULL;
  96 static ms_try_statement_t  *current_try       = NULL;
  97 static linkage_kind_t       current_linkage   = LINKAGE_INVALID;
  98 static goto_statement_t    *goto_first        = NULL;
  99 static goto_statement_t   **goto_anchor       = NULL;
 100 static label_statement_t   *label_first       = NULL;
 101 static label_statement_t  **label_anchor      = NULL;
 102 /** current translation unit. */
 103 static translation_unit_t  *unit              = NULL;
 104 /** true if we are in a type property context (evaluation only for type) */
 105 static bool                 in_type_prop      = false;
 106 /** true if we are in an __extension__ context. */
 107 static bool                 in_gcc_extension  = false;
 108 static struct obstack       temp_obst;
 109 static entity_t            *anonymous_entity;
 110 static declaration_t      **incomplete_arrays;
 111
 112
 113 #define PUSH_PARENT(stmt)                          \
 114         statement_t *const prev_parent = current_parent; \
 115         ((void)(current_parent = (stmt)))
 116 #define POP_PARENT ((void)(current_parent = prev_parent))
 117
 118 /** special symbol used for anonymous entities. */
 119 static symbol_t *sym_anonymous = NULL;
 120
 121 /** The token anchor set */
 122 static unsigned char token_anchor_set[T_LAST_TOKEN];
 123
 124 /** The current source position. */
 125 #define HERE (&token.source_position)
 126
 127 /** true if we are in GCC mode. */
 128 #define GNU_MODE ((c_mode & _GNUC) || in_gcc_extension)
 129
 130 static statement_t *parse_compound_statement(bool inside_expression_statement);
 131 static statement_t *parse_statement(void);
 132
 133 static expression_t *parse_subexpression(precedence_t);
 134 static expression_t *parse_expression(void);
 135 static type_t       *parse_typename(void);
 136 static void          parse_externals(void);
 137 static void          parse_external(void);
 138
 139 static void parse_compound_type_entries(compound_t *compound_declaration);
 140
 141 static void check_call_argument(type_t          *expected_type,
 142                                                                 call_argument_t *argument, unsigned pos);
 143
 144 typedef enum declarator_flags_t {
 145         DECL_FLAGS_NONE             = 0,
 146         DECL_MAY_BE_ABSTRACT        = 1U << 0,
 147         DECL_CREATE_COMPOUND_MEMBER = 1U << 1,
 148         DECL_IS_PARAMETER           = 1U << 2
 149 } declarator_flags_t;
 150
 151 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
 152                                   declarator_flags_t flags);
 153
 154 static void semantic_comparison(binary_expression_t *expression);
 155
 156 #define STORAGE_CLASSES       \
 157         STORAGE_CLASSES_NO_EXTERN \
 158         case T_extern:
 159
 160 #define STORAGE_CLASSES_NO_EXTERN \
 161         case T_typedef:         \
 162         case T_static:          \
 163         case T_auto:            \
 164         case T_register:        \
 165         case T___thread:
 166
 167 #define TYPE_QUALIFIERS     \
 168         case T_const:           \
 169         case T_restrict:        \
 170         case T_volatile:        \
 171         case T_inline:          \
 172         case T__forceinline:    \
 173         case T___attribute__:
 174
 175 #define COMPLEX_SPECIFIERS  \
 176         case T__Complex:
 177 #define IMAGINARY_SPECIFIERS \
 178         case T__Imaginary:
 179
 180 #define TYPE_SPECIFIERS       \
 181         case T__Bool:             \
 182         case T___builtin_va_list: \
 183         case T___typeof__:        \
 184         case T__declspec:         \
 185         case T_bool:              \
 186         case T_char:              \
 187         case T_double:            \
 188         case T_enum:              \
 189         case T_float:             \
 190         case T_int:               \
 191         case T_long:              \
 192         case T_short:             \
 193         case T_signed:            \
 194         case T_struct:            \
 195         case T_union:             \
 196         case T_unsigned:          \
 197         case T_void:              \
 198         case T_wchar_t:           \
 199         case T__int8:             \
 200         case T__int16:            \
 201         case T__int32:            \
 202         case T__int64:            \
 203         case T__int128:           \
 204         COMPLEX_SPECIFIERS        \
 205         IMAGINARY_SPECIFIERS
 206
 207 #define DECLARATION_START   \
 208         STORAGE_CLASSES         \
 209         TYPE_QUALIFIERS         \
 210         TYPE_SPECIFIERS
 211
 212 #define DECLARATION_START_NO_EXTERN \
 213         STORAGE_CLASSES_NO_EXTERN       \
 214         TYPE_QUALIFIERS                 \
 215         TYPE_SPECIFIERS
 216
 217 #define TYPENAME_START      \
 218         TYPE_QUALIFIERS         \
 219         TYPE_SPECIFIERS
 220
 221 #define EXPRESSION_START              \
 222         case '!':                         \
 223         case '&':                         \
 224         case '(':                         \
 225         case '*':                         \
 226         case '+':                         \
 227         case '-':                         \
 228         case '~':                         \
 229         case T_ANDAND:                    \
 230         case T_CHARACTER_CONSTANT:        \
 231         case T_FLOATINGPOINT:             \
 232         case T_FLOATINGPOINT_HEXADECIMAL: \
 233         case T_INTEGER:                   \
 234         case T_INTEGER_HEXADECIMAL:       \
 235         case T_INTEGER_OCTAL:             \
 236         case T_MINUSMINUS:                \
 237         case T_PLUSPLUS:                  \
 238         case T_STRING_LITERAL:            \
 239         case T_WIDE_CHARACTER_CONSTANT:   \
 240         case T_WIDE_STRING_LITERAL:       \
 241         case T___FUNCDNAME__:             \
 242         case T___FUNCSIG__:               \
 243         case T___FUNCTION__:              \
 244         case T___PRETTY_FUNCTION__:       \
 245         case T___alignof__:               \
 246         case T___builtin_classify_type:   \
 247         case T___builtin_constant_p:      \
 248         case T___builtin_isgreater:       \
 249         case T___builtin_isgreaterequal:  \
 250         case T___builtin_isless:          \
 251         case T___builtin_islessequal:     \
 252         case T___builtin_islessgreater:   \
 253         case T___builtin_isunordered:     \
 254         case T___builtin_offsetof:        \
 255         case T___builtin_va_arg:          \
 256         case T___builtin_va_copy:         \
 257         case T___builtin_va_start:        \
 258         case T___func__:                  \
 259         case T___noop:                    \
 260         case T__assume:                   \
 261         case T_delete:                    \
 262         case T_false:                     \
 263         case T_sizeof:                    \
 264         case T_throw:                     \
 265         case T_true:
 266
 267 /**
 268  * Returns the size of a statement node.
 269  *
 270  * @param kind  the statement kind
 271  */
 272 static size_t get_statement_struct_size(statement_kind_t kind)
 273 {
 274         static const size_t sizes[] = {
 275                 [STATEMENT_INVALID]     = sizeof(invalid_statement_t),
 276                 [STATEMENT_EMPTY]       = sizeof(empty_statement_t),
 277                 [STATEMENT_COMPOUND]    = sizeof(compound_statement_t),
 278                 [STATEMENT_RETURN]      = sizeof(return_statement_t),
 279                 [STATEMENT_DECLARATION] = sizeof(declaration_statement_t),
 280                 [STATEMENT_IF]          = sizeof(if_statement_t),
 281                 [STATEMENT_SWITCH]      = sizeof(switch_statement_t),
 282                 [STATEMENT_EXPRESSION]  = sizeof(expression_statement_t),
 283                 [STATEMENT_CONTINUE]    = sizeof(statement_base_t),
 284                 [STATEMENT_BREAK]       = sizeof(statement_base_t),
 285                 [STATEMENT_GOTO]        = sizeof(goto_statement_t),
 286                 [STATEMENT_LABEL]       = sizeof(label_statement_t),
 287                 [STATEMENT_CASE_LABEL]  = sizeof(case_label_statement_t),
 288                 [STATEMENT_WHILE]       = sizeof(while_statement_t),
 289                 [STATEMENT_DO_WHILE]    = sizeof(do_while_statement_t),
 290                 [STATEMENT_FOR]         = sizeof(for_statement_t),
 291                 [STATEMENT_ASM]         = sizeof(asm_statement_t),
 292                 [STATEMENT_MS_TRY]      = sizeof(ms_try_statement_t),
 293                 [STATEMENT_LEAVE]       = sizeof(leave_statement_t)
 294         };
 295         assert(kind < lengthof(sizes));
 296         assert(sizes[kind] != 0);
 297         return sizes[kind];
 298 }
 299
 300 /**
 301  * Returns the size of an expression node.
 302  *
 303  * @param kind  the expression kind
 304  */
 305 static size_t get_expression_struct_size(expression_kind_t kind)
 306 {
 307         static const size_t sizes[] = {
 308                 [EXPR_INVALID]                    = sizeof(expression_base_t),
 309                 [EXPR_REFERENCE]                  = sizeof(reference_expression_t),
 310                 [EXPR_REFERENCE_ENUM_VALUE]       = sizeof(reference_expression_t),
 311                 [EXPR_LITERAL_INTEGER]            = sizeof(literal_expression_t),
 312                 [EXPR_LITERAL_INTEGER_OCTAL]      = sizeof(literal_expression_t),
 313                 [EXPR_LITERAL_INTEGER_HEXADECIMAL]= sizeof(literal_expression_t),
 314                 [EXPR_LITERAL_FLOATINGPOINT]      = sizeof(literal_expression_t),
 315                 [EXPR_LITERAL_FLOATINGPOINT_HEXADECIMAL] = sizeof(literal_expression_t),
 316                 [EXPR_LITERAL_CHARACTER]          = sizeof(literal_expression_t),
 317                 [EXPR_LITERAL_WIDE_CHARACTER]     = sizeof(literal_expression_t),
 318                 [EXPR_STRING_LITERAL]             = sizeof(string_literal_expression_t),
 319                 [EXPR_WIDE_STRING_LITERAL]        = sizeof(string_literal_expression_t),
 320                 [EXPR_COMPOUND_LITERAL]           = sizeof(compound_literal_expression_t),
 321                 [EXPR_CALL]                       = sizeof(call_expression_t),
 322                 [EXPR_UNARY_FIRST]                = sizeof(unary_expression_t),
 323                 [EXPR_BINARY_FIRST]               = sizeof(binary_expression_t),
 324                 [EXPR_CONDITIONAL]                = sizeof(conditional_expression_t),
 325                 [EXPR_SELECT]                     = sizeof(select_expression_t),
 326                 [EXPR_ARRAY_ACCESS]               = sizeof(array_access_expression_t),
 327                 [EXPR_SIZEOF]                     = sizeof(typeprop_expression_t),
 328                 [EXPR_ALIGNOF]                    = sizeof(typeprop_expression_t),
 329                 [EXPR_CLASSIFY_TYPE]              = sizeof(classify_type_expression_t),
 330                 [EXPR_FUNCNAME]                   = sizeof(funcname_expression_t),
 331                 [EXPR_BUILTIN_CONSTANT_P]         = sizeof(builtin_constant_expression_t),
 332                 [EXPR_BUILTIN_TYPES_COMPATIBLE_P] = sizeof(builtin_types_compatible_expression_t),
 333                 [EXPR_OFFSETOF]                   = sizeof(offsetof_expression_t),
 334                 [EXPR_VA_START]                   = sizeof(va_start_expression_t),
 335                 [EXPR_VA_ARG]                     = sizeof(va_arg_expression_t),
 336                 [EXPR_VA_COPY]                    = sizeof(va_copy_expression_t),
 337                 [EXPR_STATEMENT]                  = sizeof(statement_expression_t),
 338                 [EXPR_LABEL_ADDRESS]              = sizeof(label_address_expression_t),
 339         };
 340         if (kind >= EXPR_UNARY_FIRST && kind <= EXPR_UNARY_LAST) {
 341                 return sizes[EXPR_UNARY_FIRST];
 342         }
 343         if (kind >= EXPR_BINARY_FIRST && kind <= EXPR_BINARY_LAST) {
 344                 return sizes[EXPR_BINARY_FIRST];
 345         }
 346         assert(kind < lengthof(sizes));
 347         assert(sizes[kind] != 0);
 348         return sizes[kind];
 349 }
 350
 351 /**
 352  * Allocate a statement node of given kind and initialize all
 353  * fields with zero. Sets its source position to the position
 354  * of the current token.
 355  */
 356 static statement_t *allocate_statement_zero(statement_kind_t kind)
 357 {
 358         size_t       size = get_statement_struct_size(kind);
 359         statement_t *res  = allocate_ast_zero(size);
 360
 361         res->base.kind            = kind;
 362         res->base.parent          = current_parent;
 363         res->base.source_position = token.source_position;
 364         return res;
 365 }
 366
 367 /**
 368  * Allocate an expression node of given kind and initialize all
 369  * fields with zero.
 370  *
 371  * @param kind  the kind of the expression to allocate
 372  */
 373 static expression_t *allocate_expression_zero(expression_kind_t kind)
 374 {
 375         size_t        size = get_expression_struct_size(kind);
 376         expression_t *res  = allocate_ast_zero(size);
 377
 378         res->base.kind            = kind;
 379         res->base.type            = type_error_type;
 380         res->base.source_position = token.source_position;
 381         return res;
 382 }
 383
 384 /**
 385  * Creates a new invalid expression at the source position
 386  * of the current token.
 387  */
 388 static expression_t *create_invalid_expression(void)
 389 {
 390         return allocate_expression_zero(EXPR_INVALID);
 391 }
 392
 393 /**
 394  * Creates a new invalid statement.
 395  */
 396 static statement_t *create_invalid_statement(void)
 397 {
 398         return allocate_statement_zero(STATEMENT_INVALID);
 399 }
 400
 401 /**
 402  * Allocate a new empty statement.
 403  */
 404 static statement_t *create_empty_statement(void)
 405 {
 406         return allocate_statement_zero(STATEMENT_EMPTY);
 407 }
 408
 409 static function_parameter_t *allocate_parameter(type_t *const type)
 410 {
 411         function_parameter_t *const param
 412                 = obstack_alloc(type_obst, sizeof(*param));
 413         memset(param, 0, sizeof(*param));
 414         param->type = type;
 415         return param;
 416 }
 417
 418 /**
 419  * Returns the size of an initializer node.
 420  *
 421  * @param kind  the initializer kind
 422  */
 423 static size_t get_initializer_size(initializer_kind_t kind)
 424 {
 425         static const size_t sizes[] = {
 426                 [INITIALIZER_VALUE]       = sizeof(initializer_value_t),
 427                 [INITIALIZER_STRING]      = sizeof(initializer_string_t),
 428                 [INITIALIZER_WIDE_STRING] = sizeof(initializer_wide_string_t),
 429                 [INITIALIZER_LIST]        = sizeof(initializer_list_t),
 430                 [INITIALIZER_DESIGNATOR]  = sizeof(initializer_designator_t)
 431         };
 432         assert(kind < lengthof(sizes));
 433         assert(sizes[kind] != 0);
 434         return sizes[kind];
 435 }
 436
 437 /**
 438  * Allocate an initializer node of given kind and initialize all
 439  * fields with zero.
 440  */
 441 static initializer_t *allocate_initializer_zero(initializer_kind_t kind)
 442 {
 443         initializer_t *result = allocate_ast_zero(get_initializer_size(kind));
 444         result->kind          = kind;
 445
 446         return result;
 447 }
 448
 449 /**
 450  * Returns the index of the top element of the environment stack.
 451  */
 452 static size_t environment_top(void)
 453 {
 454         return ARR_LEN(environment_stack);
 455 }
 456
 457 /**
 458  * Returns the index of the top element of the global label stack.
 459  */
 460 static size_t label_top(void)
 461 {
 462         return ARR_LEN(label_stack);
 463 }
 464
 465 /**
 466  * Return the next token.
 467  */
 468 static inline void next_token(void)
 469 {
 470         token                              = lookahead_buffer[lookahead_bufpos];
 471         lookahead_buffer[lookahead_bufpos] = lexer_token;
 472         lexer_next_token();
 473
 474         lookahead_bufpos = (lookahead_bufpos + 1) % MAX_LOOKAHEAD;
 475
 476 #ifdef PRINT_TOKENS
 477         print_token(stderr, &token);
 478         fprintf(stderr, "\n");
 479 #endif
 480 }
 481
 482 static inline bool next_if(int const type)
 483 {
 484         if (token.type == type) {
 485                 next_token();
 486                 return true;
 487         } else {
 488                 return false;
 489         }
 490 }
 491
 492 /**
 493  * Return the next token with a given lookahead.
 494  */
 495 static inline const token_t *look_ahead(size_t num)
 496 {
 497         assert(0 < num && num <= MAX_LOOKAHEAD);
 498         size_t pos = (lookahead_bufpos + num - 1) % MAX_LOOKAHEAD;
 499         return &lookahead_buffer[pos];
 500 }
 501
 502 /**
 503  * Adds a token type to the token type anchor set (a multi-set).
 504  */
 505 static void add_anchor_token(int token_type)
 506 {
 507         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 508         ++token_anchor_set[token_type];
 509 }
 510
 511 /**
 512  * Set the number of tokens types of the given type
 513  * to zero and return the old count.
 514  */
 515 static int save_and_reset_anchor_state(int token_type)
 516 {
 517         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 518         int count = token_anchor_set[token_type];
 519         token_anchor_set[token_type] = 0;
 520         return count;
 521 }
 522
 523 /**
 524  * Restore the number of token types to the given count.
 525  */
 526 static void restore_anchor_state(int token_type, int count)
 527 {
 528         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 529         token_anchor_set[token_type] = count;
 530 }
 531
 532 /**
 533  * Remove a token type from the token type anchor set (a multi-set).
 534  */
 535 static void rem_anchor_token(int token_type)
 536 {
 537         assert(0 <= token_type && token_type < T_LAST_TOKEN);
 538         assert(token_anchor_set[token_type] != 0);
 539         --token_anchor_set[token_type];
 540 }
 541
 542 /**
 543  * Return true if the token type of the current token is
 544  * in the anchor set.
 545  */
 546 static bool at_anchor(void)
 547 {
 548         if (token.type < 0)
 549                 return false;
 550         return token_anchor_set[token.type];
 551 }
 552
 553 /**
 554  * Eat tokens until a matching token type is found.
 555  */
 556 static void eat_until_matching_token(int type)
 557 {
 558         int end_token;
 559         switch (type) {
 560                 case '(': end_token = ')';  break;
 561                 case '{': end_token = '}';  break;
 562                 case '[': end_token = ']';  break;
 563                 default:  end_token = type; break;
 564         }
 565
 566         unsigned parenthesis_count = 0;
 567         unsigned brace_count       = 0;
 568         unsigned bracket_count     = 0;
 569         while (token.type        != end_token ||
 570                parenthesis_count != 0         ||
 571                brace_count       != 0         ||
 572                bracket_count     != 0) {
 573                 switch (token.type) {
 574                 case T_EOF: return;
 575                 case '(': ++parenthesis_count; break;
 576                 case '{': ++brace_count;       break;
 577                 case '[': ++bracket_count;     break;
 578
 579                 case ')':
 580                         if (parenthesis_count > 0)
 581                                 --parenthesis_count;
 582                         goto check_stop;
 583
 584                 case '}':
 585                         if (brace_count > 0)
 586                                 --brace_count;
 587                         goto check_stop;
 588
 589                 case ']':
 590                         if (bracket_count > 0)
 591                                 --bracket_count;
 592 check_stop:
 593                         if (token.type        == end_token &&
 594                             parenthesis_count == 0         &&
 595                             brace_count       == 0         &&
 596                             bracket_count     == 0)
 597                                 return;
 598                         break;
 599
 600                 default:
 601                         break;
 602                 }
 603                 next_token();
 604         }
 605 }
 606
 607 /**
 608  * Eat input tokens until an anchor is found.
 609  */
 610 static void eat_until_anchor(void)
 611 {
 612         while (token_anchor_set[token.type] == 0) {
 613                 if (token.type == '(' || token.type == '{' || token.type == '[')
 614                         eat_until_matching_token(token.type);
 615                 next_token();
 616         }
 617 }
 618
 619 /**
 620  * Eat a whole block from input tokens.
 621  */
 622 static void eat_block(void)
 623 {
 624         eat_until_matching_token('{');
 625         next_if('}');
 626 }
 627
 628 #define eat(token_type) (assert(token.type == (token_type)), next_token())
 629
 630 /**
 631  * Report a parse error because an expected token was not found.
 632  */
 633 static
 634 #if defined __GNUC__ && __GNUC__ >= 4
 635 __attribute__((sentinel))
 636 #endif
 637 void parse_error_expected(const char *message, ...)
 638 {
 639         if (message != NULL) {
 640                 errorf(HERE, "%s", message);
 641         }
 642         va_list ap;
 643         va_start(ap, message);
 644         errorf(HERE, "got %K, expected %#k", &token, &ap, ", ");
 645         va_end(ap);
 646 }
 647
 648 /**
 649  * Report an incompatible type.
 650  */
 651 static void type_error_incompatible(const char *msg,
 652                 const source_position_t *source_position, type_t *type1, type_t *type2)
 653 {
 654         errorf(source_position, "%s, incompatible types: '%T' - '%T'",
 655                msg, type1, type2);
 656 }
 657
 658 /**
 659  * Expect the current token is the expected token.
 660  * If not, generate an error, eat the current statement,
 661  * and goto the error_label label.
 662  */
 663 #define expect(expected, error_label)                     \
 664         do {                                                  \
 665                 if (UNLIKELY(token.type != (expected))) {         \
 666                         parse_error_expected(NULL, (expected), NULL); \
 667                         add_anchor_token(expected);                   \
 668                         eat_until_anchor();                           \
 669                         next_if((expected));                          \
 670                         rem_anchor_token(expected);                   \
 671                         goto error_label;                             \
 672                 }                                                 \
 673                 next_token();                                     \
 674         } while (0)
 675
 676 /**
 677  * Push a given scope on the scope stack and make it the
 678  * current scope
 679  */
 680 static scope_t *scope_push(scope_t *new_scope)
 681 {
 682         if (current_scope != NULL) {
 683                 new_scope->depth = current_scope->depth + 1;
 684         }
 685
 686         scope_t *old_scope = current_scope;
 687         current_scope      = new_scope;
 688         return old_scope;
 689 }
 690
 691 /**
 692  * Pop the current scope from the scope stack.
 693  */
 694 static void scope_pop(scope_t *old_scope)
 695 {
 696         current_scope = old_scope;
 697 }
 698
 699 /**
 700  * Search an entity by its symbol in a given namespace.
 701  */
 702 static entity_t *get_entity(const symbol_t *const symbol,
 703                             namespace_tag_t namespc)
 704 {
 705         assert(namespc != NAMESPACE_INVALID);
 706         entity_t *entity = symbol->entity;
 707         for (; entity != NULL; entity = entity->base.symbol_next) {
 708                 if (entity->base.namespc == namespc)
 709                         return entity;
 710         }
 711
 712         return NULL;
 713 }
 714
 715 /* §6.2.3:1 24)  There is only one name space for tags even though three are
 716  * possible. */
 717 static entity_t *get_tag(symbol_t const *const symbol,
 718                          entity_kind_tag_t const kind)
 719 {
 720         entity_t *entity = get_entity(symbol, NAMESPACE_TAG);
 721         if (entity != NULL && entity->kind != kind) {
 722                 errorf(HERE,
 723                                 "'%Y' defined as wrong kind of tag (previous definition %P)",
 724                                 symbol, &entity->base.source_position);
 725                 entity = NULL;
 726         }
 727         return entity;
 728 }
 729
 730 /**
 731  * pushs an entity on the environment stack and links the corresponding symbol
 732  * it.
 733  */
 734 static void stack_push(stack_entry_t **stack_ptr, entity_t *entity)
 735 {
 736         symbol_t           *symbol  = entity->base.symbol;
 737         entity_namespace_t  namespc = entity->base.namespc;
 738         assert(namespc != NAMESPACE_INVALID);
 739
 740         /* replace/add entity into entity list of the symbol */
 741         entity_t **anchor;
 742         entity_t  *iter;
 743         for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 744                 iter = *anchor;
 745                 if (iter == NULL)
 746                         break;
 747
 748                 /* replace an entry? */
 749                 if (iter->base.namespc == namespc) {
 750                         entity->base.symbol_next = iter->base.symbol_next;
 751                         break;
 752                 }
 753         }
 754         *anchor = entity;
 755
 756         /* remember old declaration */
 757         stack_entry_t entry;
 758         entry.symbol     = symbol;
 759         entry.old_entity = iter;
 760         entry.namespc    = namespc;
 761         ARR_APP1(stack_entry_t, *stack_ptr, entry);
 762 }
 763
 764 /**
 765  * Push an entity on the environment stack.
 766  */
 767 static void environment_push(entity_t *entity)
 768 {
 769         assert(entity->base.source_position.input_name != NULL);
 770         assert(entity->base.parent_scope != NULL);
 771         stack_push(&environment_stack, entity);
 772 }
 773
 774 /**
 775  * Push a declaration on the global label stack.
 776  *
 777  * @param declaration  the declaration
 778  */
 779 static void label_push(entity_t *label)
 780 {
 781         /* we abuse the parameters scope as parent for the labels */
 782         label->base.parent_scope = &current_function->parameters;
 783         stack_push(&label_stack, label);
 784 }
 785
 786 /**
 787  * pops symbols from the environment stack until @p new_top is the top element
 788  */
 789 static void stack_pop_to(stack_entry_t **stack_ptr, size_t new_top)
 790 {
 791         stack_entry_t *stack = *stack_ptr;
 792         size_t         top   = ARR_LEN(stack);
 793         size_t         i;
 794
 795         assert(new_top <= top);
 796         if (new_top == top)
 797                 return;
 798
 799         for (i = top; i > new_top; --i) {
 800                 stack_entry_t *entry = &stack[i - 1];
 801
 802                 entity_t           *old_entity = entry->old_entity;
 803                 symbol_t           *symbol     = entry->symbol;
 804                 entity_namespace_t  namespc    = entry->namespc;
 805
 806                 /* replace with old_entity/remove */
 807                 entity_t **anchor;
 808                 entity_t  *iter;
 809                 for (anchor = &symbol->entity; ; anchor = &iter->base.symbol_next) {
 810                         iter = *anchor;
 811                         assert(iter != NULL);
 812                         /* replace an entry? */
 813                         if (iter->base.namespc == namespc)
 814                                 break;
 815                 }
 816
 817                 /* restore definition from outer scopes (if there was one) */
 818                 if (old_entity != NULL) {
 819                         old_entity->base.symbol_next = iter->base.symbol_next;
 820                         *anchor                      = old_entity;
 821                 } else {
 822                         /* remove entry from list */
 823                         *anchor = iter->base.symbol_next;
 824                 }
 825         }
 826
 827         ARR_SHRINKLEN(*stack_ptr, new_top);
 828 }
 829
 830 /**
 831  * Pop all entries from the environment stack until the new_top
 832  * is reached.
 833  *
 834  * @param new_top  the new stack top
 835  */
 836 static void environment_pop_to(size_t new_top)
 837 {
 838         stack_pop_to(&environment_stack, new_top);
 839 }
 840
 841 /**
 842  * Pop all entries from the global label stack until the new_top
 843  * is reached.
 844  *
 845  * @param new_top  the new stack top
 846  */
 847 static void label_pop_to(size_t new_top)
 848 {
 849         stack_pop_to(&label_stack, new_top);
 850 }
 851
 852 static int get_akind_rank(atomic_type_kind_t akind)
 853 {
 854         return (int) akind;
 855 }
 856
 857 /**
 858  * Return the type rank for an atomic type.
 859  */
 860 static int get_rank(const type_t *type)
 861 {
 862         assert(!is_typeref(type));
 863         if (type->kind == TYPE_ENUM)
 864                 return get_akind_rank(type->enumt.akind);
 865
 866         assert(type->kind == TYPE_ATOMIC);
 867         return get_akind_rank(type->atomic.akind);
 868 }
 869
 870 /**
 871  * §6.3.1.1:2  Do integer promotion for a given type.
 872  *
 873  * @param type  the type to promote
 874  * @return the promoted type
 875  */
 876 static type_t *promote_integer(type_t *type)
 877 {
 878         if (type->kind == TYPE_BITFIELD)
 879                 type = type->bitfield.base_type;
 880
 881         if (get_rank(type) < get_akind_rank(ATOMIC_TYPE_INT))
 882                 type = type_int;
 883
 884         return type;
 885 }
 886
 887 /**
 888  * Create a cast expression.
 889  *
 890  * @param expression  the expression to cast
 891  * @param dest_type   the destination type
 892  */
 893 static expression_t *create_cast_expression(expression_t *expression,
 894                                             type_t *dest_type)
 895 {
 896         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST_IMPLICIT);
 897
 898         cast->unary.value = expression;
 899         cast->base.type   = dest_type;
 900
 901         return cast;
 902 }
 903
 904 /**
 905  * Check if a given expression represents a null pointer constant.
 906  *
 907  * @param expression  the expression to check
 908  */
 909 static bool is_null_pointer_constant(const expression_t *expression)
 910 {
 911         /* skip void* cast */
 912         if (expression->kind == EXPR_UNARY_CAST ||
 913                         expression->kind == EXPR_UNARY_CAST_IMPLICIT) {
 914                 type_t *const type = skip_typeref(expression->base.type);
 915                 if (types_compatible(type, type_void_ptr))
 916                         expression = expression->unary.value;
 917         }
 918
 919         type_t *const type = skip_typeref(expression->base.type);
 920         if (!is_type_integer(type))
 921                 return false;
 922         switch (is_constant_expression(expression)) {
 923                 case EXPR_CLASS_ERROR:    return true;
 924                 case EXPR_CLASS_CONSTANT: return !fold_constant_to_bool(expression);
 925                 default:                  return false;
 926         }
 927 }
 928
 929 /**
 930  * Create an implicit cast expression.
 931  *
 932  * @param expression  the expression to cast
 933  * @param dest_type   the destination type
 934  */
 935 static expression_t *create_implicit_cast(expression_t *expression,
 936                                           type_t *dest_type)
 937 {
 938         type_t *const source_type = expression->base.type;
 939
 940         if (source_type == dest_type)
 941                 return expression;
 942
 943         return create_cast_expression(expression, dest_type);
 944 }
 945
 946 typedef enum assign_error_t {
 947         ASSIGN_SUCCESS,
 948         ASSIGN_ERROR_INCOMPATIBLE,
 949         ASSIGN_ERROR_POINTER_QUALIFIER_MISSING,
 950         ASSIGN_WARNING_POINTER_INCOMPATIBLE,
 951         ASSIGN_WARNING_POINTER_FROM_INT,
 952         ASSIGN_WARNING_INT_FROM_POINTER
 953 } assign_error_t;
 954
 955 static void report_assign_error(assign_error_t error, type_t *orig_type_left,
 956                                 const expression_t *const right,
 957                                 const char *context,
 958                                 const source_position_t *source_position)
 959 {
 960         type_t *const orig_type_right = right->base.type;
 961         type_t *const type_left       = skip_typeref(orig_type_left);
 962         type_t *const type_right      = skip_typeref(orig_type_right);
 963
 964         switch (error) {
 965         case ASSIGN_SUCCESS:
 966                 return;
 967         case ASSIGN_ERROR_INCOMPATIBLE:
 968                 errorf(source_position,
 969                        "destination type '%T' in %s is incompatible with type '%T'",
 970                        orig_type_left, context, orig_type_right);
 971                 return;
 972
 973         case ASSIGN_ERROR_POINTER_QUALIFIER_MISSING: {
 974                 if (warning.other) {
 975                         type_t *points_to_left  = skip_typeref(type_left->pointer.points_to);
 976                         type_t *points_to_right = skip_typeref(type_right->pointer.points_to);
 977
 978                         /* the left type has all qualifiers from the right type */
 979                         unsigned missing_qualifiers
 980                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
 981                         warningf(source_position,
 982                                         "destination type '%T' in %s from type '%T' lacks qualifiers '%Q' in pointer target type",
 983                                         orig_type_left, context, orig_type_right, missing_qualifiers);
 984                 }
 985                 return;
 986         }
 987
 988         case ASSIGN_WARNING_POINTER_INCOMPATIBLE:
 989                 if (warning.other) {
 990                         warningf(source_position,
 991                                         "destination type '%T' in %s is incompatible with '%E' of type '%T'",
 992                                         orig_type_left, context, right, orig_type_right);
 993                 }
 994                 return;
 995
 996         case ASSIGN_WARNING_POINTER_FROM_INT:
 997                 if (warning.other) {
 998                         warningf(source_position,
 999                                         "%s makes pointer '%T' from integer '%T' without a cast",
1000                                         context, orig_type_left, orig_type_right);
1001                 }
1002                 return;
1003
1004         case ASSIGN_WARNING_INT_FROM_POINTER:
1005                 if (warning.other) {
1006                         warningf(source_position,
1007                                         "%s makes integer '%T' from pointer '%T' without a cast",
1008                                         context, orig_type_left, orig_type_right);
1009                 }
1010                 return;
1011
1012         default:
1013                 panic("invalid error value");
1014         }
1015 }
1016
1017 /** Implements the rules from §6.5.16.1 */
1018 static assign_error_t semantic_assign(type_t *orig_type_left,
1019                                       const expression_t *const right)
1020 {
1021         type_t *const orig_type_right = right->base.type;
1022         type_t *const type_left       = skip_typeref(orig_type_left);
1023         type_t *const type_right      = skip_typeref(orig_type_right);
1024
1025         if (is_type_pointer(type_left)) {
1026                 if (is_null_pointer_constant(right)) {
1027                         return ASSIGN_SUCCESS;
1028                 } else if (is_type_pointer(type_right)) {
1029                         type_t *points_to_left
1030                                 = skip_typeref(type_left->pointer.points_to);
1031                         type_t *points_to_right
1032                                 = skip_typeref(type_right->pointer.points_to);
1033                         assign_error_t res = ASSIGN_SUCCESS;
1034
1035                         /* the left type has all qualifiers from the right type */
1036                         unsigned missing_qualifiers
1037                                 = points_to_right->base.qualifiers & ~points_to_left->base.qualifiers;
1038                         if (missing_qualifiers != 0) {
1039                                 res = ASSIGN_ERROR_POINTER_QUALIFIER_MISSING;
1040                         }
1041
1042                         points_to_left  = get_unqualified_type(points_to_left);
1043                         points_to_right = get_unqualified_type(points_to_right);
1044
1045                         if (is_type_atomic(points_to_left, ATOMIC_TYPE_VOID))
1046                                 return res;
1047
1048                         if (is_type_atomic(points_to_right, ATOMIC_TYPE_VOID)) {
1049                                 /* ISO/IEC 14882:1998(E) §C.1.2:6 */
1050                                 return c_mode & _CXX ? ASSIGN_ERROR_INCOMPATIBLE : res;
1051                         }
1052
1053                         if (!types_compatible(points_to_left, points_to_right)) {
1054                                 return ASSIGN_WARNING_POINTER_INCOMPATIBLE;
1055                         }
1056
1057                         return res;
1058                 } else if (is_type_integer(type_right)) {
1059                         return ASSIGN_WARNING_POINTER_FROM_INT;
1060                 }
1061         } else if ((is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) ||
1062                         (is_type_atomic(type_left, ATOMIC_TYPE_BOOL)
1063                                 && is_type_pointer(type_right))) {
1064                 return ASSIGN_SUCCESS;
1065         } else if (is_type_compound(type_left) && is_type_compound(type_right)) {
1066                 type_t *const unqual_type_left  = get_unqualified_type(type_left);
1067                 type_t *const unqual_type_right = get_unqualified_type(type_right);
1068                 if (types_compatible(unqual_type_left, unqual_type_right)) {
1069                         return ASSIGN_SUCCESS;
1070                 }
1071         } else if (is_type_integer(type_left) && is_type_pointer(type_right)) {
1072                 return ASSIGN_WARNING_INT_FROM_POINTER;
1073         }
1074
1075         if (!is_type_valid(type_left) || !is_type_valid(type_right))
1076                 return ASSIGN_SUCCESS;
1077
1078         return ASSIGN_ERROR_INCOMPATIBLE;
1079 }
1080
1081 static expression_t *parse_constant_expression(void)
1082 {
1083         expression_t *result = parse_subexpression(PREC_CONDITIONAL);
1084
1085         if (is_constant_expression(result) == EXPR_CLASS_VARIABLE) {
1086                 errorf(&result->base.source_position,
1087                        "expression '%E' is not constant", result);
1088         }
1089
1090         return result;
1091 }
1092
1093 static expression_t *parse_assignment_expression(void)
1094 {
1095         return parse_subexpression(PREC_ASSIGNMENT);
1096 }
1097
1098 static void warn_string_concat(const source_position_t *pos)
1099 {
1100         if (warning.traditional) {
1101                 warningf(pos, "traditional C rejects string constant concatenation");
1102         }
1103 }
1104
1105 static string_t parse_string_literals(void)
1106 {
1107         assert(token.type == T_STRING_LITERAL);
1108         string_t result = token.literal;
1109
1110         next_token();
1111
1112         while (token.type == T_STRING_LITERAL) {
1113                 warn_string_concat(&token.source_position);
1114                 result = concat_strings(&result, &token.literal);
1115                 next_token();
1116         }
1117
1118         return result;
1119 }
1120
1121 /**
1122  * compare two string, ignoring double underscores on the second.
1123  */
1124 static int strcmp_underscore(const char *s1, const char *s2)
1125 {
1126         if (s2[0] == '_' && s2[1] == '_') {
1127                 size_t len2 = strlen(s2);
1128                 size_t len1 = strlen(s1);
1129                 if (len1 == len2-4 && s2[len2-2] == '_' && s2[len2-1] == '_') {
1130                         return strncmp(s1, s2+2, len2-4);
1131                 }
1132         }
1133
1134         return strcmp(s1, s2);
1135 }
1136
1137 static attribute_t *allocate_attribute_zero(attribute_kind_t kind)
1138 {
1139         attribute_t *attribute = allocate_ast_zero(sizeof(*attribute));
1140         attribute->kind        = kind;
1141         return attribute;
1142 }
1143
1144 /**
1145  * Parse (gcc) attribute argument. From gcc comments in gcc source:
1146  *
1147  *  attribute:
1148  *    __attribute__ ( ( attribute-list ) )
1149  *
1150  *  attribute-list:
1151  *    attrib
1152  *    attribute_list , attrib
1153  *
1154  *  attrib:
1155  *    empty
1156  *    any-word
1157  *    any-word ( identifier )
1158  *    any-word ( identifier , nonempty-expr-list )
1159  *    any-word ( expr-list )
1160  *
1161  *  where the "identifier" must not be declared as a type, and
1162  *  "any-word" may be any identifier (including one declared as a
1163  *  type), a reserved word storage class specifier, type specifier or
1164  *  type qualifier.  ??? This still leaves out most reserved keywords
1165  *  (following the old parser), shouldn't we include them, and why not
1166  *  allow identifiers declared as types to start the arguments?
1167  *
1168  *  Matze: this all looks confusing and little systematic, so we're even less
1169  *  strict and parse any list of things which are identifiers or
1170  *  (assignment-)expressions.
1171  */
1172 static attribute_argument_t *parse_attribute_arguments(void)
1173 {
1174         attribute_argument_t  *first  = NULL;
1175         attribute_argument_t **anchor = &first;
1176         if (token.type != ')') do {
1177                 attribute_argument_t *argument = allocate_ast_zero(sizeof(*argument));
1178
1179                 /* is it an identifier */
1180                 if (token.type == T_IDENTIFIER
1181                                 && (look_ahead(1)->type == ',' || look_ahead(1)->type == ')')) {
1182                         symbol_t *symbol   = token.symbol;
1183                         argument->kind     = ATTRIBUTE_ARGUMENT_SYMBOL;
1184                         argument->v.symbol = symbol;
1185                         next_token();
1186                 } else {
1187                         /* must be an expression */
1188                         expression_t *expression = parse_assignment_expression();
1189
1190                         argument->kind         = ATTRIBUTE_ARGUMENT_EXPRESSION;
1191                         argument->v.expression = expression;
1192                 }
1193
1194                 /* append argument */
1195                 *anchor = argument;
1196                 anchor  = &argument->next;
1197         } while (next_if(','));
1198         expect(')', end_error);
1199
1200         return first;
1201
1202 end_error:
1203         /* TODO... */
1204         return first;
1205 }
1206
1207 static attribute_t *parse_attribute_asm(void)
1208 {
1209         eat(T_asm);
1210
1211         attribute_t *attribute = allocate_attribute_zero(ATTRIBUTE_GNU_ASM);
1212
1213         expect('(', end_error);
1214         attribute->a.arguments = parse_attribute_arguments();
1215         return attribute;
1216
1217 end_error:
1218         return NULL;
1219 }
1220
1221 static symbol_t *get_symbol_from_token(void)
1222 {
1223         switch(token.type) {
1224         case T_IDENTIFIER:
1225                 return token.symbol;
1226         case T_auto:
1227         case T_char:
1228         case T_double:
1229         case T_enum:
1230         case T_extern:
1231         case T_float:
1232         case T_int:
1233         case T_long:
1234         case T_register:
1235         case T_short:
1236         case T_static:
1237         case T_struct:
1238         case T_union:
1239         case T_unsigned:
1240         case T_void:
1241         case T_bool:
1242         case T__Bool:
1243         case T_class:
1244         case T_explicit:
1245         case T_export:
1246         case T_wchar_t:
1247         case T_const:
1248         case T_signed:
1249         case T___real__:
1250         case T___imag__:
1251         case T_restrict:
1252         case T_volatile:
1253         case T_inline:
1254                 /* maybe we need more tokens ... add them on demand */
1255                 return get_token_symbol(&token);
1256         default:
1257                 return NULL;
1258         }
1259 }
1260
1261 static attribute_t *parse_attribute_gnu_single(void)
1262 {
1263         /* parse "any-word" */
1264         symbol_t *symbol = get_symbol_from_token();
1265         if (symbol == NULL) {
1266                 parse_error_expected("while parsing attribute((", T_IDENTIFIER, NULL);
1267                 return NULL;
1268         }
1269
1270         const char *name = symbol->string;
1271         next_token();
1272
1273         attribute_kind_t kind;
1274         for (kind = ATTRIBUTE_GNU_FIRST; kind <= ATTRIBUTE_GNU_LAST; ++kind) {
1275                 const char *attribute_name = get_attribute_name(kind);
1276                 if (attribute_name != NULL
1277                                 && strcmp_underscore(attribute_name, name) == 0)
1278                         break;
1279         }
1280
1281         if (kind >= ATTRIBUTE_GNU_LAST) {
1282                 if (warning.attribute) {
1283                         warningf(HERE, "unknown attribute '%s' ignored", name);
1284                 }
1285                 /* TODO: we should still save the attribute in the list... */
1286                 kind = ATTRIBUTE_UNKNOWN;
1287         }
1288
1289         attribute_t *attribute = allocate_attribute_zero(kind);
1290
1291         /* parse arguments */
1292         if (next_if('('))
1293                 attribute->a.arguments = parse_attribute_arguments();
1294
1295         return attribute;
1296 }
1297
1298 static attribute_t *parse_attribute_gnu(void)
1299 {
1300         attribute_t  *first  = NULL;
1301         attribute_t **anchor = &first;
1302
1303         eat(T___attribute__);
1304         expect('(', end_error);
1305         expect('(', end_error);
1306
1307         if (token.type != ')') do {
1308                 attribute_t *attribute = parse_attribute_gnu_single();
1309                 if (attribute == NULL)
1310                         goto end_error;
1311
1312                 *anchor = attribute;
1313                 anchor  = &attribute->next;
1314         } while (next_if(','));
1315         expect(')', end_error);
1316         expect(')', end_error);
1317
1318 end_error:
1319         return first;
1320 }
1321
1322 /** Parse attributes. */
1323 static attribute_t *parse_attributes(attribute_t *first)
1324 {
1325         attribute_t **anchor = &first;
1326         for (;;) {
1327                 while (*anchor != NULL)
1328                         anchor = &(*anchor)->next;
1329
1330                 attribute_t *attribute;
1331                 switch (token.type) {
1332                 case T___attribute__:
1333                         attribute = parse_attribute_gnu();
1334                         if (attribute == NULL)
1335                                 continue;
1336                         break;
1337
1338                 case T_asm:
1339                         attribute = parse_attribute_asm();
1340                         break;
1341
1342                 case T_cdecl:
1343                         next_token();
1344                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_CDECL);
1345                         break;
1346
1347                 case T__fastcall:
1348                         next_token();
1349                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_FASTCALL);
1350                         break;
1351
1352                 case T__forceinline:
1353                         next_token();
1354                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_FORCEINLINE);
1355                         break;
1356
1357                 case T__stdcall:
1358                         next_token();
1359                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_STDCALL);
1360                         break;
1361
1362                 case T___thiscall:
1363                         next_token();
1364                         /* TODO record modifier */
1365                         if (warning.other)
1366                                 warningf(HERE, "Ignoring declaration modifier %K", &token);
1367                         attribute = allocate_attribute_zero(ATTRIBUTE_MS_THISCALL);
1368                         break;
1369
1370                 default:
1371                         return first;
1372                 }
1373
1374                 *anchor = attribute;
1375                 anchor  = &attribute->next;
1376         }
1377 }
1378
1379 static void mark_vars_read(expression_t *expr, entity_t *lhs_ent);
1380
1381 static entity_t *determine_lhs_ent(expression_t *const expr,
1382                                    entity_t *lhs_ent)
1383 {
1384         switch (expr->kind) {
1385                 case EXPR_REFERENCE: {
1386                         entity_t *const entity = expr->reference.entity;
1387                         /* we should only find variables as lvalues... */
1388                         if (entity->base.kind != ENTITY_VARIABLE
1389                                         && entity->base.kind != ENTITY_PARAMETER)
1390                                 return NULL;
1391
1392                         return entity;
1393                 }
1394
1395                 case EXPR_ARRAY_ACCESS: {
1396                         expression_t *const ref = expr->array_access.array_ref;
1397                         entity_t     *      ent = NULL;
1398                         if (is_type_array(skip_typeref(revert_automatic_type_conversion(ref)))) {
1399                                 ent     = determine_lhs_ent(ref, lhs_ent);
1400                                 lhs_ent = ent;
1401                         } else {
1402                                 mark_vars_read(expr->select.compound, lhs_ent);
1403                         }
1404                         mark_vars_read(expr->array_access.index, lhs_ent);
1405                         return ent;
1406                 }
1407
1408                 case EXPR_SELECT: {
1409                         if (is_type_compound(skip_typeref(expr->base.type))) {
1410                                 return determine_lhs_ent(expr->select.compound, lhs_ent);
1411                         } else {
1412                                 mark_vars_read(expr->select.compound, lhs_ent);
1413                                 return NULL;
1414                         }
1415                 }
1416
1417                 case EXPR_UNARY_DEREFERENCE: {
1418                         expression_t *const val = expr->unary.value;
1419                         if (val->kind == EXPR_UNARY_TAKE_ADDRESS) {
1420                                 /* *&x is a NOP */
1421                                 return determine_lhs_ent(val->unary.value, lhs_ent);
1422                         } else {
1423                                 mark_vars_read(val, NULL);
1424                                 return NULL;
1425                         }
1426                 }
1427
1428                 default:
1429                         mark_vars_read(expr, NULL);
1430                         return NULL;
1431         }
1432 }
1433
1434 #define ENT_ANY ((entity_t*)-1)
1435
1436 /**
1437  * Mark declarations, which are read.  This is used to detect variables, which
1438  * are never read.
1439  * Example:
1440  * x = x + 1;
1441  *   x is not marked as "read", because it is only read to calculate its own new
1442  *   value.
1443  *
1444  * x += y; y += x;
1445  *   x and y are not detected as "not read", because multiple variables are
1446  *   involved.
1447  */
1448 static void mark_vars_read(expression_t *const expr, entity_t *lhs_ent)
1449 {
1450         switch (expr->kind) {
1451                 case EXPR_REFERENCE: {
1452                         entity_t *const entity = expr->reference.entity;
1453                         if (entity->kind != ENTITY_VARIABLE
1454                                         && entity->kind != ENTITY_PARAMETER)
1455                                 return;
1456
1457                         if (lhs_ent != entity && lhs_ent != ENT_ANY) {
1458                                 if (entity->kind == ENTITY_VARIABLE) {
1459                                         entity->variable.read = true;
1460                                 } else {
1461                                         entity->parameter.read = true;
1462                                 }
1463                         }
1464                         return;
1465                 }
1466
1467                 case EXPR_CALL:
1468                         // TODO respect pure/const
1469                         mark_vars_read(expr->call.function, NULL);
1470                         for (call_argument_t *arg = expr->call.arguments; arg != NULL; arg = arg->next) {
1471                                 mark_vars_read(arg->expression, NULL);
1472                         }
1473                         return;
1474
1475                 case EXPR_CONDITIONAL:
1476                         // TODO lhs_decl should depend on whether true/false have an effect
1477                         mark_vars_read(expr->conditional.condition, NULL);
1478                         if (expr->conditional.true_expression != NULL)
1479                                 mark_vars_read(expr->conditional.true_expression, lhs_ent);
1480                         mark_vars_read(expr->conditional.false_expression, lhs_ent);
1481                         return;
1482
1483                 case EXPR_SELECT:
1484                         if (lhs_ent == ENT_ANY
1485                                         && !is_type_compound(skip_typeref(expr->base.type)))
1486                                 lhs_ent = NULL;
1487                         mark_vars_read(expr->select.compound, lhs_ent);
1488                         return;
1489
1490                 case EXPR_ARRAY_ACCESS: {
1491                         expression_t *const ref = expr->array_access.array_ref;
1492                         mark_vars_read(ref, lhs_ent);
1493                         lhs_ent = determine_lhs_ent(ref, lhs_ent);
1494                         mark_vars_read(expr->array_access.index, lhs_ent);
1495                         return;
1496                 }
1497
1498                 case EXPR_VA_ARG:
1499                         mark_vars_read(expr->va_arge.ap, lhs_ent);
1500                         return;
1501
1502                 case EXPR_VA_COPY:
1503                         mark_vars_read(expr->va_copye.src, lhs_ent);
1504                         return;
1505
1506                 case EXPR_UNARY_CAST:
1507                         /* Special case: Use void cast to mark a variable as "read" */
1508                         if (is_type_atomic(skip_typeref(expr->base.type), ATOMIC_TYPE_VOID))
1509                                 lhs_ent = NULL;
1510                         goto unary;
1511
1512
1513                 case EXPR_UNARY_THROW:
1514                         if (expr->unary.value == NULL)
1515                                 return;
1516                         /* FALLTHROUGH */
1517                 case EXPR_UNARY_DEREFERENCE:
1518                 case EXPR_UNARY_DELETE:
1519                 case EXPR_UNARY_DELETE_ARRAY:
1520                         if (lhs_ent == ENT_ANY)
1521                                 lhs_ent = NULL;
1522                         goto unary;
1523
1524                 case EXPR_UNARY_NEGATE:
1525                 case EXPR_UNARY_PLUS:
1526                 case EXPR_UNARY_BITWISE_NEGATE:
1527                 case EXPR_UNARY_NOT:
1528                 case EXPR_UNARY_TAKE_ADDRESS:
1529                 case EXPR_UNARY_POSTFIX_INCREMENT:
1530                 case EXPR_UNARY_POSTFIX_DECREMENT:
1531                 case EXPR_UNARY_PREFIX_INCREMENT:
1532                 case EXPR_UNARY_PREFIX_DECREMENT:
1533                 case EXPR_UNARY_CAST_IMPLICIT:
1534                 case EXPR_UNARY_ASSUME:
1535 unary:
1536                         mark_vars_read(expr->unary.value, lhs_ent);
1537                         return;
1538
1539                 case EXPR_BINARY_ADD:
1540                 case EXPR_BINARY_SUB:
1541                 case EXPR_BINARY_MUL:
1542                 case EXPR_BINARY_DIV:
1543                 case EXPR_BINARY_MOD:
1544                 case EXPR_BINARY_EQUAL:
1545                 case EXPR_BINARY_NOTEQUAL:
1546                 case EXPR_BINARY_LESS:
1547                 case EXPR_BINARY_LESSEQUAL:
1548                 case EXPR_BINARY_GREATER:
1549                 case EXPR_BINARY_GREATEREQUAL:
1550                 case EXPR_BINARY_BITWISE_AND:
1551                 case EXPR_BINARY_BITWISE_OR:
1552                 case EXPR_BINARY_BITWISE_XOR:
1553                 case EXPR_BINARY_LOGICAL_AND:
1554                 case EXPR_BINARY_LOGICAL_OR:
1555                 case EXPR_BINARY_SHIFTLEFT:
1556                 case EXPR_BINARY_SHIFTRIGHT:
1557                 case EXPR_BINARY_COMMA:
1558                 case EXPR_BINARY_ISGREATER:
1559                 case EXPR_BINARY_ISGREATEREQUAL:
1560                 case EXPR_BINARY_ISLESS:
1561                 case EXPR_BINARY_ISLESSEQUAL:
1562                 case EXPR_BINARY_ISLESSGREATER:
1563                 case EXPR_BINARY_ISUNORDERED:
1564                         mark_vars_read(expr->binary.left,  lhs_ent);
1565                         mark_vars_read(expr->binary.right, lhs_ent);
1566                         return;
1567
1568                 case EXPR_BINARY_ASSIGN:
1569                 case EXPR_BINARY_MUL_ASSIGN:
1570                 case EXPR_BINARY_DIV_ASSIGN:
1571                 case EXPR_BINARY_MOD_ASSIGN:
1572                 case EXPR_BINARY_ADD_ASSIGN:
1573                 case EXPR_BINARY_SUB_ASSIGN:
1574                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:
1575                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:
1576                 case EXPR_BINARY_BITWISE_AND_ASSIGN:
1577                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:
1578                 case EXPR_BINARY_BITWISE_OR_ASSIGN: {
1579                         if (lhs_ent == ENT_ANY)
1580                                 lhs_ent = NULL;
1581                         lhs_ent = determine_lhs_ent(expr->binary.left, lhs_ent);
1582                         mark_vars_read(expr->binary.right, lhs_ent);
1583                         return;
1584                 }
1585
1586                 case EXPR_VA_START:
1587                         determine_lhs_ent(expr->va_starte.ap, lhs_ent);
1588                         return;
1589
1590                 EXPR_LITERAL_CASES
1591                 case EXPR_UNKNOWN:
1592                 case EXPR_INVALID:
1593                 case EXPR_STRING_LITERAL:
1594                 case EXPR_WIDE_STRING_LITERAL:
1595                 case EXPR_COMPOUND_LITERAL: // TODO init?
1596                 case EXPR_SIZEOF:
1597                 case EXPR_CLASSIFY_TYPE:
1598                 case EXPR_ALIGNOF:
1599                 case EXPR_FUNCNAME:
1600                 case EXPR_BUILTIN_CONSTANT_P:
1601                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P:
1602                 case EXPR_OFFSETOF:
1603                 case EXPR_STATEMENT: // TODO
1604                 case EXPR_LABEL_ADDRESS:
1605                 case EXPR_REFERENCE_ENUM_VALUE:
1606                         return;
1607         }
1608
1609         panic("unhandled expression");
1610 }
1611
1612 static designator_t *parse_designation(void)
1613 {
1614         designator_t  *result = NULL;
1615         designator_t **anchor = &result;
1616
1617         for (;;) {
1618                 designator_t *designator;
1619                 switch (token.type) {
1620                 case '[':
1621                         designator = allocate_ast_zero(sizeof(designator[0]));
1622                         designator->source_position = token.source_position;
1623                         next_token();
1624                         add_anchor_token(']');
1625                         designator->array_index = parse_constant_expression();
1626                         rem_anchor_token(']');
1627                         expect(']', end_error);
1628                         break;
1629                 case '.':
1630                         designator = allocate_ast_zero(sizeof(designator[0]));
1631                         designator->source_position = token.source_position;
1632                         next_token();
1633                         if (token.type != T_IDENTIFIER) {
1634                                 parse_error_expected("while parsing designator",
1635                                                      T_IDENTIFIER, NULL);
1636                                 return NULL;
1637                         }
1638                         designator->symbol = token.symbol;
1639                         next_token();
1640                         break;
1641                 default:
1642                         expect('=', end_error);
1643                         return result;
1644                 }
1645
1646                 assert(designator != NULL);
1647                 *anchor = designator;
1648                 anchor  = &designator->next;
1649         }
1650 end_error:
1651         return NULL;
1652 }
1653
1654 static initializer_t *initializer_from_string(array_type_t *const type,
1655                                               const string_t *const string)
1656 {
1657         /* TODO: check len vs. size of array type */
1658         (void) type;
1659
1660         initializer_t *initializer = allocate_initializer_zero(INITIALIZER_STRING);
1661         initializer->string.string = *string;
1662
1663         return initializer;
1664 }
1665
1666 static initializer_t *initializer_from_wide_string(array_type_t *const type,
1667                                                    const string_t *const string)
1668 {
1669         /* TODO: check len vs. size of array type */
1670         (void) type;
1671
1672         initializer_t *const initializer =
1673                 allocate_initializer_zero(INITIALIZER_WIDE_STRING);
1674         initializer->wide_string.string = *string;
1675
1676         return initializer;
1677 }
1678
1679 /**
1680  * Build an initializer from a given expression.
1681  */
1682 static initializer_t *initializer_from_expression(type_t *orig_type,
1683                                                   expression_t *expression)
1684 {
1685         /* TODO check that expression is a constant expression */
1686
1687         /* §6.7.8.14/15 char array may be initialized by string literals */
1688         type_t *type           = skip_typeref(orig_type);
1689         type_t *expr_type_orig = expression->base.type;
1690         type_t *expr_type      = skip_typeref(expr_type_orig);
1691
1692         if (is_type_array(type) && expr_type->kind == TYPE_POINTER) {
1693                 array_type_t *const array_type   = &type->array;
1694                 type_t       *const element_type = skip_typeref(array_type->element_type);
1695
1696                 if (element_type->kind == TYPE_ATOMIC) {
1697                         atomic_type_kind_t akind = element_type->atomic.akind;
1698                         switch (expression->kind) {
1699                         case EXPR_STRING_LITERAL:
1700                                 if (akind == ATOMIC_TYPE_CHAR
1701                                                 || akind == ATOMIC_TYPE_SCHAR
1702                                                 || akind == ATOMIC_TYPE_UCHAR) {
1703                                         return initializer_from_string(array_type,
1704                                                         &expression->string_literal.value);
1705                                 }
1706                                 break;
1707
1708                         case EXPR_WIDE_STRING_LITERAL: {
1709                                 type_t *bare_wchar_type = skip_typeref(type_wchar_t);
1710                                 if (get_unqualified_type(element_type) == bare_wchar_type) {
1711                                         return initializer_from_wide_string(array_type,
1712                                                         &expression->string_literal.value);
1713                                 }
1714                                 break;
1715                         }
1716
1717                         default:
1718                                 break;
1719                         }
1720                 }
1721         }
1722
1723         assign_error_t error = semantic_assign(type, expression);
1724         if (error == ASSIGN_ERROR_INCOMPATIBLE)
1725                 return NULL;
1726         report_assign_error(error, type, expression, "initializer",
1727                             &expression->base.source_position);
1728
1729         initializer_t *const result = allocate_initializer_zero(INITIALIZER_VALUE);
1730         result->value.value = create_implicit_cast(expression, type);
1731
1732         return result;
1733 }
1734
1735 /**
1736  * Checks if a given expression can be used as an constant initializer.
1737  */
1738 static bool is_initializer_constant(const expression_t *expression)
1739 {
1740         return
1741                 is_constant_expression(expression) != EXPR_CLASS_VARIABLE ||
1742                 is_address_constant(expression)    != EXPR_CLASS_VARIABLE;
1743 }
1744
1745 /**
1746  * Parses an scalar initializer.
1747  *
1748  * §6.7.8.11; eat {} without warning
1749  */
1750 static initializer_t *parse_scalar_initializer(type_t *type,
1751                                                bool must_be_constant)
1752 {
1753         /* there might be extra {} hierarchies */
1754         int braces = 0;
1755         if (next_if('{')) {
1756                 if (warning.other)
1757                         warningf(HERE, "extra curly braces around scalar initializer");
1758                 do {
1759                         ++braces;
1760                 } while (next_if('{'));
1761         }
1762
1763         expression_t *expression = parse_assignment_expression();
1764         mark_vars_read(expression, NULL);
1765         if (must_be_constant && !is_initializer_constant(expression)) {
1766                 errorf(&expression->base.source_position,
1767                        "initialisation expression '%E' is not constant",
1768                        expression);
1769         }
1770
1771         initializer_t *initializer = initializer_from_expression(type, expression);
1772
1773         if (initializer == NULL) {
1774                 errorf(&expression->base.source_position,
1775                        "expression '%E' (type '%T') doesn't match expected type '%T'",
1776                        expression, expression->base.type, type);
1777                 /* TODO */
1778                 return NULL;
1779         }
1780
1781         bool additional_warning_displayed = false;
1782         while (braces > 0) {
1783                 next_if(',');
1784                 if (token.type != '}') {
1785                         if (!additional_warning_displayed && warning.other) {
1786                                 warningf(HERE, "additional elements in scalar initializer");
1787                                 additional_warning_displayed = true;
1788                         }
1789                 }
1790                 eat_block();
1791                 braces--;
1792         }
1793
1794         return initializer;
1795 }
1796
1797 /**
1798  * An entry in the type path.
1799  */
1800 typedef struct type_path_entry_t type_path_entry_t;
1801 struct type_path_entry_t {
1802         type_t *type;       /**< the upper top type. restored to path->top_tye if this entry is popped. */
1803         union {
1804                 size_t         index;          /**< For array types: the current index. */
1805                 declaration_t *compound_entry; /**< For compound types: the current declaration. */
1806         } v;
1807 };
1808
1809 /**
1810  * A type path expression a position inside compound or array types.
1811  */
1812 typedef struct type_path_t type_path_t;
1813 struct type_path_t {
1814         type_path_entry_t *path;         /**< An flexible array containing the current path. */
1815         type_t            *top_type;     /**< type of the element the path points */
1816         size_t             max_index;    /**< largest index in outermost array */
1817 };
1818
1819 /**
1820  * Prints a type path for debugging.
1821  */
1822 static __attribute__((unused)) void debug_print_type_path(
1823                 const type_path_t *path)
1824 {
1825         size_t len = ARR_LEN(path->path);
1826
1827         for (size_t i = 0; i < len; ++i) {
1828                 const type_path_entry_t *entry = & path->path[i];
1829
1830                 type_t *type = skip_typeref(entry->type);
1831                 if (is_type_compound(type)) {
1832                         /* in gcc mode structs can have no members */
1833                         if (entry->v.compound_entry == NULL) {
1834                                 assert(i == len-1);
1835                                 continue;
1836                         }
1837                         fprintf(stderr, ".%s",
1838                                 entry->v.compound_entry->base.symbol->string);
1839                 } else if (is_type_array(type)) {
1840                         fprintf(stderr, "[%u]", (unsigned) entry->v.index);
1841                 } else {
1842                         fprintf(stderr, "-INVALID-");
1843                 }
1844         }
1845         if (path->top_type != NULL) {
1846                 fprintf(stderr, "  (");
1847                 print_type(path->top_type);
1848                 fprintf(stderr, ")");
1849         }
1850 }
1851
1852 /**
1853  * Return the top type path entry, ie. in a path
1854  * (type).a.b returns the b.
1855  */
1856 static type_path_entry_t *get_type_path_top(const type_path_t *path)
1857 {
1858         size_t len = ARR_LEN(path->path);
1859         assert(len > 0);
1860         return &path->path[len-1];
1861 }
1862
1863 /**
1864  * Enlarge the type path by an (empty) element.
1865  */
1866 static type_path_entry_t *append_to_type_path(type_path_t *path)
1867 {
1868         size_t len = ARR_LEN(path->path);
1869         ARR_RESIZE(type_path_entry_t, path->path, len+1);
1870
1871         type_path_entry_t *result = & path->path[len];
1872         memset(result, 0, sizeof(result[0]));
1873         return result;
1874 }
1875
1876 /**
1877  * Descending into a sub-type. Enter the scope of the current top_type.
1878  */
1879 static void descend_into_subtype(type_path_t *path)
1880 {
1881         type_t *orig_top_type = path->top_type;
1882         type_t *top_type      = skip_typeref(orig_top_type);
1883
1884         type_path_entry_t *top = append_to_type_path(path);
1885         top->type              = top_type;
1886
1887         if (is_type_compound(top_type)) {
1888                 compound_t *compound  = top_type->compound.compound;
1889                 entity_t   *entry     = compound->members.entities;
1890
1891                 if (entry != NULL) {
1892                         assert(entry->kind == ENTITY_COMPOUND_MEMBER);
1893                         top->v.compound_entry = &entry->declaration;
1894                         path->top_type = entry->declaration.type;
1895                 } else {
1896                         path->top_type = NULL;
1897                 }
1898         } else if (is_type_array(top_type)) {
1899                 top->v.index   = 0;
1900                 path->top_type = top_type->array.element_type;
1901         } else {
1902                 assert(!is_type_valid(top_type));
1903         }
1904 }
1905
1906 /**
1907  * Pop an entry from the given type path, ie. returning from
1908  * (type).a.b to (type).a
1909  */
1910 static void ascend_from_subtype(type_path_t *path)
1911 {
1912         type_path_entry_t *top = get_type_path_top(path);
1913
1914         path->top_type = top->type;
1915
1916         size_t len = ARR_LEN(path->path);
1917         ARR_RESIZE(type_path_entry_t, path->path, len-1);
1918 }
1919
1920 /**
1921  * Pop entries from the given type path until the given
1922  * path level is reached.
1923  */
1924 static void ascend_to(type_path_t *path, size_t top_path_level)
1925 {
1926         size_t len = ARR_LEN(path->path);
1927
1928         while (len > top_path_level) {
1929                 ascend_from_subtype(path);
1930                 len = ARR_LEN(path->path);
1931         }
1932 }
1933
1934 static bool walk_designator(type_path_t *path, const designator_t *designator,
1935                             bool used_in_offsetof)
1936 {
1937         for (; designator != NULL; designator = designator->next) {
1938                 type_path_entry_t *top       = get_type_path_top(path);
1939                 type_t            *orig_type = top->type;
1940
1941                 type_t *type = skip_typeref(orig_type);
1942
1943                 if (designator->symbol != NULL) {
1944                         symbol_t *symbol = designator->symbol;
1945                         if (!is_type_compound(type)) {
1946                                 if (is_type_valid(type)) {
1947                                         errorf(&designator->source_position,
1948                                                "'.%Y' designator used for non-compound type '%T'",
1949                                                symbol, orig_type);
1950                                 }
1951
1952                                 top->type             = type_error_type;
1953                                 top->v.compound_entry = NULL;
1954                                 orig_type             = type_error_type;
1955                         } else {
1956                                 compound_t *compound = type->compound.compound;
1957                                 entity_t   *iter     = compound->members.entities;
1958                                 for (; iter != NULL; iter = iter->base.next) {
1959                                         if (iter->base.symbol == symbol) {
1960                                                 break;
1961                                         }
1962                                 }
1963                                 if (iter == NULL) {
1964                                         errorf(&designator->source_position,
1965                                                "'%T' has no member named '%Y'", orig_type, symbol);
1966                                         goto failed;
1967                                 }
1968                                 assert(iter->kind == ENTITY_COMPOUND_MEMBER);
1969                                 if (used_in_offsetof) {
1970                                         type_t *real_type = skip_typeref(iter->declaration.type);
1971                                         if (real_type->kind == TYPE_BITFIELD) {
1972                                                 errorf(&designator->source_position,
1973                                                        "offsetof designator '%Y' must not specify bitfield",
1974                                                        symbol);
1975                                                 goto failed;
1976                                         }
1977                                 }
1978
1979                                 top->type             = orig_type;
1980                                 top->v.compound_entry = &iter->declaration;
1981                                 orig_type             = iter->declaration.type;
1982                         }
1983                 } else {
1984                         expression_t *array_index = designator->array_index;
1985                         assert(designator->array_index != NULL);
1986
1987                         if (!is_type_array(type)) {
1988                                 if (is_type_valid(type)) {
1989                                         errorf(&designator->source_position,
1990                                                "[%E] designator used for non-array type '%T'",
1991                                                array_index, orig_type);
1992                                 }
1993                                 goto failed;
1994                         }
1995
1996                         long index = fold_constant_to_int(array_index);
1997                         if (!used_in_offsetof) {
1998                                 if (index < 0) {
1999                                         errorf(&designator->source_position,
2000                                                "array index [%E] must be positive", array_index);
2001                                 } else if (type->array.size_constant) {
2002                                         long array_size = type->array.size;
2003                                         if (index >= array_size) {
2004                                                 errorf(&designator->source_position,
2005                                                        "designator [%E] (%d) exceeds array size %d",
2006                                                        array_index, index, array_size);
2007                                         }
2008                                 }
2009                         }
2010
2011                         top->type    = orig_type;
2012                         top->v.index = (size_t) index;
2013                         orig_type    = type->array.element_type;
2014                 }
2015                 path->top_type = orig_type;
2016
2017                 if (designator->next != NULL) {
2018                         descend_into_subtype(path);
2019                 }
2020         }
2021         return true;
2022
2023 failed:
2024         return false;
2025 }
2026
2027 static void advance_current_object(type_path_t *path, size_t top_path_level)
2028 {
2029         type_path_entry_t *top = get_type_path_top(path);
2030
2031         type_t *type = skip_typeref(top->type);
2032         if (is_type_union(type)) {
2033                 /* in unions only the first element is initialized */
2034                 top->v.compound_entry = NULL;
2035         } else if (is_type_struct(type)) {
2036                 declaration_t *entry = top->v.compound_entry;
2037
2038                 entity_t *next_entity = entry->base.next;
2039                 if (next_entity != NULL) {
2040                         assert(is_declaration(next_entity));
2041                         entry = &next_entity->declaration;
2042                 } else {
2043                         entry = NULL;
2044                 }
2045
2046                 top->v.compound_entry = entry;
2047                 if (entry != NULL) {
2048                         path->top_type = entry->type;
2049                         return;
2050                 }
2051         } else if (is_type_array(type)) {
2052                 assert(is_type_array(type));
2053
2054                 top->v.index++;
2055
2056                 if (!type->array.size_constant || top->v.index < type->array.size) {
2057                         return;
2058                 }
2059         } else {
2060                 assert(!is_type_valid(type));
2061                 return;
2062         }
2063
2064         /* we're past the last member of the current sub-aggregate, try if we
2065          * can ascend in the type hierarchy and continue with another subobject */
2066         size_t len = ARR_LEN(path->path);
2067
2068         if (len > top_path_level) {
2069                 ascend_from_subtype(path);
2070                 advance_current_object(path, top_path_level);
2071         } else {
2072                 path->top_type = NULL;
2073         }
2074 }
2075
2076 /**
2077  * skip any {...} blocks until a closing bracket is reached.
2078  */
2079 static void skip_initializers(void)
2080 {
2081         next_if('{');
2082
2083         while (token.type != '}') {
2084                 if (token.type == T_EOF)
2085                         return;
2086                 if (token.type == '{') {
2087                         eat_block();
2088                         continue;
2089                 }
2090                 next_token();
2091         }
2092 }
2093
2094 static initializer_t *create_empty_initializer(void)
2095 {
2096         static initializer_t empty_initializer
2097                 = { .list = { { INITIALIZER_LIST }, 0 } };
2098         return &empty_initializer;
2099 }
2100
2101 /**
2102  * Parse a part of an initialiser for a struct or union,
2103  */
2104 static initializer_t *parse_sub_initializer(type_path_t *path,
2105                 type_t *outer_type, size_t top_path_level,
2106                 parse_initializer_env_t *env)
2107 {
2108         if (token.type == '}') {
2109                 /* empty initializer */
2110                 return create_empty_initializer();
2111         }
2112
2113         type_t *orig_type = path->top_type;
2114         type_t *type      = NULL;
2115
2116         if (orig_type == NULL) {
2117                 /* We are initializing an empty compound. */
2118         } else {
2119                 type = skip_typeref(orig_type);
2120         }
2121
2122         initializer_t **initializers = NEW_ARR_F(initializer_t*, 0);
2123
2124         while (true) {
2125                 designator_t *designator = NULL;
2126                 if (token.type == '.' || token.type == '[') {
2127                         designator = parse_designation();
2128                         goto finish_designator;
2129                 } else if (token.type == T_IDENTIFIER && look_ahead(1)->type == ':') {
2130                         /* GNU-style designator ("identifier: value") */
2131                         designator = allocate_ast_zero(sizeof(designator[0]));
2132                         designator->source_position = token.source_position;
2133                         designator->symbol          = token.symbol;
2134                         eat(T_IDENTIFIER);
2135                         eat(':');
2136
2137 finish_designator:
2138                         /* reset path to toplevel, evaluate designator from there */
2139                         ascend_to(path, top_path_level);
2140                         if (!walk_designator(path, designator, false)) {
2141                                 /* can't continue after designation error */
2142                                 goto end_error;
2143                         }
2144
2145                         initializer_t *designator_initializer
2146                                 = allocate_initializer_zero(INITIALIZER_DESIGNATOR);
2147                         designator_initializer->designator.designator = designator;
2148                         ARR_APP1(initializer_t*, initializers, designator_initializer);
2149
2150                         orig_type = path->top_type;
2151                         type      = orig_type != NULL ? skip_typeref(orig_type) : NULL;
2152                 }
2153
2154                 initializer_t *sub;
2155
2156                 if (token.type == '{') {
2157                         if (type != NULL && is_type_scalar(type)) {
2158                                 sub = parse_scalar_initializer(type, env->must_be_constant);
2159                         } else {
2160                                 eat('{');
2161                                 if (type == NULL) {
2162                                         if (env->entity != NULL) {
2163                                                 errorf(HERE,
2164                                                      "extra brace group at end of initializer for '%Y'",
2165                                                      env->entity->base.symbol);
2166                                         } else {
2167                                                 errorf(HERE, "extra brace group at end of initializer");
2168                                         }
2169                                 } else
2170                                         descend_into_subtype(path);
2171
2172                                 add_anchor_token('}');
2173                                 sub = parse_sub_initializer(path, orig_type, top_path_level+1,
2174                                                             env);
2175                                 rem_anchor_token('}');
2176
2177                                 if (type != NULL) {
2178                                         ascend_from_subtype(path);
2179                                         expect('}', end_error);
2180                                 } else {
2181                                         expect('}', end_error);
2182                                         goto error_parse_next;
2183                                 }
2184                         }
2185                 } else {
2186                         /* must be an expression */
2187                         expression_t *expression = parse_assignment_expression();
2188                         mark_vars_read(expression, NULL);
2189
2190                         if (env->must_be_constant && !is_initializer_constant(expression)) {
2191                                 errorf(&expression->base.source_position,
2192                                        "Initialisation expression '%E' is not constant",
2193                                        expression);
2194                         }
2195
2196                         if (type == NULL) {
2197                                 /* we are already outside, ... */
2198                                 if (outer_type == NULL)
2199                                         goto error_parse_next;
2200                                 type_t *const outer_type_skip = skip_typeref(outer_type);
2201                                 if (is_type_compound(outer_type_skip) &&
2202                                     !outer_type_skip->compound.compound->complete) {
2203                                         goto error_parse_next;
2204                                 }
2205                                 goto error_excess;
2206                         }
2207
2208                         /* handle { "string" } special case */
2209                         if ((expression->kind == EXPR_STRING_LITERAL
2210                                         || expression->kind == EXPR_WIDE_STRING_LITERAL)
2211                                         && outer_type != NULL) {
2212                                 sub = initializer_from_expression(outer_type, expression);
2213                                 if (sub != NULL) {
2214                                         next_if(',');
2215                                         if (token.type != '}' && warning.other) {
2216                                                 warningf(HERE, "excessive elements in initializer for type '%T'",
2217                                                                  orig_type);
2218                                         }
2219                                         /* TODO: eat , ... */
2220                                         return sub;
2221                                 }
2222                         }
2223
2224                         /* descend into subtypes until expression matches type */
2225                         while (true) {
2226                                 orig_type = path->top_type;
2227                                 type      = skip_typeref(orig_type);
2228
2229                                 sub = initializer_from_expression(orig_type, expression);
2230                                 if (sub != NULL) {
2231                                         break;
2232                                 }
2233                                 if (!is_type_valid(type)) {
2234                                         goto end_error;
2235                                 }
2236                                 if (is_type_scalar(type)) {
2237                                         errorf(&expression->base.source_position,
2238                                                         "expression '%E' doesn't match expected type '%T'",
2239                                                         expression, orig_type);
2240                                         goto end_error;
2241                                 }
2242
2243                                 descend_into_subtype(path);
2244                         }
2245                 }
2246
2247                 /* update largest index of top array */
2248                 const type_path_entry_t *first      = &path->path[0];
2249                 type_t                  *first_type = first->type;
2250                 first_type                          = skip_typeref(first_type);
2251                 if (is_type_array(first_type)) {
2252                         size_t index = first->v.index;
2253                         if (index > path->max_index)
2254                                 path->max_index = index;
2255                 }
2256
2257                 if (type != NULL) {
2258                         /* append to initializers list */
2259                         ARR_APP1(initializer_t*, initializers, sub);
2260                 } else {
2261 error_excess:
2262                         if (warning.other) {
2263                                 if (env->entity != NULL) {
2264                                         warningf(HERE, "excess elements in initializer for '%Y'",
2265                                                  env->entity->base.symbol);
2266                                 } else {
2267                                         warningf(HERE, "excess elements in initializer");
2268                                 }
2269                         }
2270                 }
2271
2272 error_parse_next:
2273                 if (token.type == '}') {
2274                         break;
2275                 }
2276                 expect(',', end_error);
2277                 if (token.type == '}') {
2278                         break;
2279                 }
2280
2281                 if (type != NULL) {
2282                         /* advance to the next declaration if we are not at the end */
2283                         advance_current_object(path, top_path_level);
2284                         orig_type = path->top_type;
2285                         if (orig_type != NULL)
2286                                 type = skip_typeref(orig_type);
2287                         else
2288                                 type = NULL;
2289                 }
2290         }
2291
2292         size_t len  = ARR_LEN(initializers);
2293         size_t size = sizeof(initializer_list_t) + len * sizeof(initializers[0]);
2294         initializer_t *result = allocate_ast_zero(size);
2295         result->kind          = INITIALIZER_LIST;
2296         result->list.len      = len;
2297         memcpy(&result->list.initializers, initializers,
2298                len * sizeof(initializers[0]));
2299
2300         DEL_ARR_F(initializers);
2301         ascend_to(path, top_path_level+1);
2302
2303         return result;
2304
2305 end_error:
2306         skip_initializers();
2307         DEL_ARR_F(initializers);
2308         ascend_to(path, top_path_level+1);
2309         return NULL;
2310 }
2311
2312 static expression_t *make_size_literal(size_t value)
2313 {
2314         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_INTEGER);
2315         literal->base.type    = type_size_t;
2316
2317         char buf[128];
2318         snprintf(buf, sizeof(buf), "%u", (unsigned) value);
2319         literal->literal.value = make_string(buf);
2320
2321         return literal;
2322 }
2323
2324 /**
2325  * Parses an initializer. Parsers either a compound literal
2326  * (env->declaration == NULL) or an initializer of a declaration.
2327  */
2328 static initializer_t *parse_initializer(parse_initializer_env_t *env)
2329 {
2330         type_t        *type      = skip_typeref(env->type);
2331         size_t         max_index = 0;
2332         initializer_t *result;
2333
2334         if (is_type_scalar(type)) {
2335                 result = parse_scalar_initializer(type, env->must_be_constant);
2336         } else if (token.type == '{') {
2337                 eat('{');
2338
2339                 type_path_t path;
2340                 memset(&path, 0, sizeof(path));
2341                 path.top_type = env->type;
2342                 path.path     = NEW_ARR_F(type_path_entry_t, 0);
2343
2344                 descend_into_subtype(&path);
2345
2346                 add_anchor_token('}');
2347                 result = parse_sub_initializer(&path, env->type, 1, env);
2348                 rem_anchor_token('}');
2349
2350                 max_index = path.max_index;
2351                 DEL_ARR_F(path.path);
2352
2353                 expect('}', end_error);
2354         } else {
2355                 /* parse_scalar_initializer() also works in this case: we simply
2356                  * have an expression without {} around it */
2357                 result = parse_scalar_initializer(type, env->must_be_constant);
2358         }
2359
2360         /* §6.7.8:22 array initializers for arrays with unknown size determine
2361          * the array type size */
2362         if (is_type_array(type) && type->array.size_expression == NULL
2363                         && result != NULL) {
2364                 size_t size;
2365                 switch (result->kind) {
2366                 case INITIALIZER_LIST:
2367                         assert(max_index != 0xdeadbeaf);
2368                         size = max_index + 1;
2369                         break;
2370
2371                 case INITIALIZER_STRING:
2372                         size = result->string.string.size;
2373                         break;
2374
2375                 case INITIALIZER_WIDE_STRING:
2376                         size = result->wide_string.string.size;
2377                         break;
2378
2379                 case INITIALIZER_DESIGNATOR:
2380                 case INITIALIZER_VALUE:
2381                         /* can happen for parse errors */
2382                         size = 0;
2383                         break;
2384
2385                 default:
2386                         internal_errorf(HERE, "invalid initializer type");
2387                 }
2388
2389                 type_t *new_type = duplicate_type(type);
2390
2391                 new_type->array.size_expression   = make_size_literal(size);
2392                 new_type->array.size_constant     = true;
2393                 new_type->array.has_implicit_size = true;
2394                 new_type->array.size              = size;
2395                 env->type = new_type;
2396         }
2397
2398         return result;
2399 end_error:
2400         return NULL;
2401 }
2402
2403 static void append_entity(scope_t *scope, entity_t *entity)
2404 {
2405         if (scope->last_entity != NULL) {
2406                 scope->last_entity->base.next = entity;
2407         } else {
2408                 scope->entities = entity;
2409         }
2410         entity->base.parent_entity = current_entity;
2411         scope->last_entity         = entity;
2412 }
2413
2414
2415 static compound_t *parse_compound_type_specifier(bool is_struct)
2416 {
2417         eat(is_struct ? T_struct : T_union);
2418
2419         symbol_t    *symbol     = NULL;
2420         entity_t    *entity     = NULL;
2421         attribute_t *attributes = NULL;
2422
2423         if (token.type == T___attribute__) {
2424                 attributes = parse_attributes(NULL);
2425         }
2426
2427         entity_kind_tag_t const kind = is_struct ? ENTITY_STRUCT : ENTITY_UNION;
2428         if (token.type == T_IDENTIFIER) {
2429                 /* the compound has a name, check if we have seen it already */
2430                 symbol = token.symbol;
2431                 next_token();
2432
2433                 entity = get_tag(symbol, kind);
2434                 if (entity != NULL) {
2435                         if (entity->base.parent_scope != current_scope &&
2436                             (token.type == '{' || token.type == ';')) {
2437                                 /* we're in an inner scope and have a definition. Shadow
2438                                  * existing definition in outer scope */
2439                                 entity = NULL;
2440                         } else if (entity->compound.complete && token.type == '{') {
2441                                 assert(symbol != NULL);
2442                                 errorf(HERE, "multiple definitions of '%s %Y' (previous definition %P)",
2443                                        is_struct ? "struct" : "union", symbol,
2444                                        &entity->base.source_position);
2445                                 /* clear members in the hope to avoid further errors */
2446                                 entity->compound.members.entities = NULL;
2447                         }
2448                 }
2449         } else if (token.type != '{') {
2450                 if (is_struct) {
2451                         parse_error_expected("while parsing struct type specifier",
2452                                              T_IDENTIFIER, '{', NULL);
2453                 } else {
2454                         parse_error_expected("while parsing union type specifier",
2455                                              T_IDENTIFIER, '{', NULL);
2456                 }
2457
2458                 return NULL;
2459         }
2460
2461         if (entity == NULL) {
2462                 entity = allocate_entity_zero(kind);
2463
2464                 entity->compound.alignment   = 1;
2465                 entity->base.namespc         = NAMESPACE_TAG;
2466                 entity->base.source_position = token.source_position;
2467                 entity->base.symbol          = symbol;
2468                 entity->base.parent_scope    = current_scope;
2469                 if (symbol != NULL) {
2470                         environment_push(entity);
2471                 }
2472                 append_entity(current_scope, entity);
2473         }
2474
2475         if (token.type == '{') {
2476                 parse_compound_type_entries(&entity->compound);
2477
2478                 /* ISO/IEC 14882:1998(E) §7.1.3:5 */
2479                 if (symbol == NULL) {
2480                         assert(anonymous_entity == NULL);
2481                         anonymous_entity = entity;
2482                 }
2483         }
2484
2485         if (attributes != NULL) {
2486                 handle_entity_attributes(attributes, entity);
2487         }
2488
2489         return &entity->compound;
2490 }
2491
2492 static void parse_enum_entries(type_t *const enum_type)
2493 {
2494         eat('{');
2495
2496         if (token.type == '}') {
2497                 errorf(HERE, "empty enum not allowed");
2498                 next_token();
2499                 return;
2500         }
2501
2502         add_anchor_token('}');
2503         do {
2504                 if (token.type != T_IDENTIFIER) {
2505                         parse_error_expected("while parsing enum entry", T_IDENTIFIER, NULL);
2506                         eat_block();
2507                         rem_anchor_token('}');
2508                         return;
2509                 }
2510
2511                 entity_t *entity             = allocate_entity_zero(ENTITY_ENUM_VALUE);
2512                 entity->enum_value.enum_type = enum_type;
2513                 entity->base.namespc         = NAMESPACE_NORMAL;
2514                 entity->base.symbol          = token.symbol;
2515                 entity->base.source_position = token.source_position;
2516                 next_token();
2517
2518                 if (next_if('=')) {
2519                         expression_t *value = parse_constant_expression();
2520
2521                         value = create_implicit_cast(value, enum_type);
2522                         entity->enum_value.value = value;
2523
2524                         /* TODO semantic */
2525                 }
2526
2527                 record_entity(entity, false);
2528         } while (next_if(',') && token.type != '}');
2529         rem_anchor_token('}');
2530
2531         expect('}', end_error);
2532
2533 end_error:
2534         ;
2535 }
2536
2537 static type_t *parse_enum_specifier(void)
2538 {
2539         entity_t *entity;
2540         symbol_t *symbol;
2541
2542         eat(T_enum);
2543         switch (token.type) {
2544                 case T_IDENTIFIER:
2545                         symbol = token.symbol;
2546                         next_token();
2547
2548                         entity = get_tag(symbol, ENTITY_ENUM);
2549                         if (entity != NULL) {
2550                                 if (entity->base.parent_scope != current_scope &&
2551                                                 (token.type == '{' || token.type == ';')) {
2552                                         /* we're in an inner scope and have a definition. Shadow
2553                                          * existing definition in outer scope */
2554                                         entity = NULL;
2555                                 } else if (entity->enume.complete && token.type == '{') {
2556                                         errorf(HERE, "multiple definitions of 'enum %Y' (previous definition %P)",
2557                                                         symbol, &entity->base.source_position);
2558                                 }
2559                         }
2560                         break;
2561
2562                 case '{':
2563                         entity = NULL;
2564                         symbol = NULL;
2565                         break;
2566
2567                 default:
2568                         parse_error_expected("while parsing enum type specifier",
2569                                         T_IDENTIFIER, '{', NULL);
2570                         return NULL;
2571         }
2572
2573         if (entity == NULL) {
2574                 entity                       = allocate_entity_zero(ENTITY_ENUM);
2575                 entity->base.namespc         = NAMESPACE_TAG;
2576                 entity->base.source_position = token.source_position;
2577                 entity->base.symbol          = symbol;
2578                 entity->base.parent_scope    = current_scope;
2579         }
2580
2581         type_t *const type = allocate_type_zero(TYPE_ENUM);
2582         type->enumt.enume  = &entity->enume;
2583         type->enumt.akind  = ATOMIC_TYPE_INT;
2584
2585         if (token.type == '{') {
2586                 if (symbol != NULL) {
2587                         environment_push(entity);
2588                 }
2589                 append_entity(current_scope, entity);
2590                 entity->enume.complete = true;
2591
2592                 parse_enum_entries(type);
2593                 parse_attributes(NULL);
2594
2595                 /* ISO/IEC 14882:1998(E) §7.1.3:5 */
2596                 if (symbol == NULL) {
2597                         assert(anonymous_entity == NULL);
2598                         anonymous_entity = entity;
2599                 }
2600         } else if (!entity->enume.complete && !(c_mode & _GNUC)) {
2601                 errorf(HERE, "'enum %Y' used before definition (incomplete enums are a GNU extension)",
2602                        symbol);
2603         }
2604
2605         return type;
2606 }
2607
2608 /**
2609  * if a symbol is a typedef to another type, return true
2610  */
2611 static bool is_typedef_symbol(symbol_t *symbol)
2612 {
2613         const entity_t *const entity = get_entity(symbol, NAMESPACE_NORMAL);
2614         return entity != NULL && entity->kind == ENTITY_TYPEDEF;
2615 }
2616
2617 static type_t *parse_typeof(void)
2618 {
2619         eat(T___typeof__);
2620
2621         type_t *type;
2622
2623         expect('(', end_error);
2624         add_anchor_token(')');
2625
2626         expression_t *expression  = NULL;
2627
2628         bool old_type_prop     = in_type_prop;
2629         bool old_gcc_extension = in_gcc_extension;
2630         in_type_prop           = true;
2631
2632         while (next_if(T___extension__)) {
2633                 /* This can be a prefix to a typename or an expression. */
2634                 in_gcc_extension = true;
2635         }
2636         switch (token.type) {
2637         case T_IDENTIFIER:
2638                 if (is_typedef_symbol(token.symbol)) {
2639         TYPENAME_START
2640                         type = parse_typename();
2641                 } else {
2642         default:
2643                         expression = parse_expression();
2644                         type       = revert_automatic_type_conversion(expression);
2645                 }
2646                 break;
2647         }
2648         in_type_prop     = old_type_prop;
2649         in_gcc_extension = old_gcc_extension;
2650
2651         rem_anchor_token(')');
2652         expect(')', end_error);
2653
2654         type_t *typeof_type              = allocate_type_zero(TYPE_TYPEOF);
2655         typeof_type->typeoft.expression  = expression;
2656         typeof_type->typeoft.typeof_type = type;
2657
2658         return typeof_type;
2659 end_error:
2660         return NULL;
2661 }
2662
2663 typedef enum specifiers_t {
2664         SPECIFIER_SIGNED    = 1 << 0,
2665         SPECIFIER_UNSIGNED  = 1 << 1,
2666         SPECIFIER_LONG      = 1 << 2,
2667         SPECIFIER_INT       = 1 << 3,
2668         SPECIFIER_DOUBLE    = 1 << 4,
2669         SPECIFIER_CHAR      = 1 << 5,
2670         SPECIFIER_WCHAR_T   = 1 << 6,
2671         SPECIFIER_SHORT     = 1 << 7,
2672         SPECIFIER_LONG_LONG = 1 << 8,
2673         SPECIFIER_FLOAT     = 1 << 9,
2674         SPECIFIER_BOOL      = 1 << 10,
2675         SPECIFIER_VOID      = 1 << 11,
2676         SPECIFIER_INT8      = 1 << 12,
2677         SPECIFIER_INT16     = 1 << 13,
2678         SPECIFIER_INT32     = 1 << 14,
2679         SPECIFIER_INT64     = 1 << 15,
2680         SPECIFIER_INT128    = 1 << 16,
2681         SPECIFIER_COMPLEX   = 1 << 17,
2682         SPECIFIER_IMAGINARY = 1 << 18,
2683 } specifiers_t;
2684
2685 static type_t *get_typedef_type(symbol_t *symbol)
2686 {
2687         entity_t *entity = get_entity(symbol, NAMESPACE_NORMAL);
2688         if (entity == NULL || entity->kind != ENTITY_TYPEDEF)
2689                 return NULL;
2690
2691         type_t *type            = allocate_type_zero(TYPE_TYPEDEF);
2692         type->typedeft.typedefe = &entity->typedefe;
2693
2694         return type;
2695 }
2696
2697 static attribute_t *parse_attribute_ms_property(attribute_t *attribute)
2698 {
2699         expect('(', end_error);
2700
2701         attribute_property_argument_t *property
2702                 = allocate_ast_zero(sizeof(*property));
2703
2704         do {
2705                 if (token.type != T_IDENTIFIER) {
2706                         parse_error_expected("while parsing property declspec",
2707                                              T_IDENTIFIER, NULL);
2708                         goto end_error;
2709                 }
2710
2711                 bool is_put;
2712                 symbol_t *symbol = token.symbol;
2713                 next_token();
2714                 if (strcmp(symbol->string, "put") == 0) {
2715                         is_put = true;
2716                 } else if (strcmp(symbol->string, "get") == 0) {
2717                         is_put = false;
2718                 } else {
2719                         errorf(HERE, "expected put or get in property declspec");
2720                         goto end_error;
2721                 }
2722                 expect('=', end_error);
2723                 if (token.type != T_IDENTIFIER) {
2724                         parse_error_expected("while parsing property declspec",
2725                                              T_IDENTIFIER, NULL);
2726                         goto end_error;
2727                 }
2728                 if (is_put) {
2729                         property->put_symbol = token.symbol;
2730                 } else {
2731                         property->get_symbol = token.symbol;
2732                 }
2733                 next_token();
2734         } while (next_if(','));
2735
2736         attribute->a.property = property;
2737
2738         expect(')', end_error);
2739
2740 end_error:
2741         return attribute;
2742 }
2743
2744 static attribute_t *parse_microsoft_extended_decl_modifier_single(void)
2745 {
2746         attribute_kind_t kind = ATTRIBUTE_UNKNOWN;
2747         if (next_if(T_restrict)) {
2748                 kind = ATTRIBUTE_MS_RESTRICT;
2749         } else if (token.type == T_IDENTIFIER) {
2750                 const char *name = token.symbol->string;
2751                 next_token();
2752                 for (attribute_kind_t k = ATTRIBUTE_MS_FIRST; k <= ATTRIBUTE_MS_LAST;
2753                      ++k) {
2754                         const char *attribute_name = get_attribute_name(k);
2755                         if (attribute_name != NULL && strcmp(attribute_name, name) == 0) {
2756                                 kind = k;
2757                                 break;
2758                         }
2759                 }
2760
2761                 if (kind == ATTRIBUTE_UNKNOWN && warning.attribute) {
2762                         warningf(HERE, "unknown __declspec '%s' ignored", name);
2763                 }
2764         } else {
2765                 parse_error_expected("while parsing __declspec", T_IDENTIFIER, NULL);
2766                 return NULL;
2767         }
2768
2769         attribute_t *attribute = allocate_attribute_zero(kind);
2770
2771         if (kind == ATTRIBUTE_MS_PROPERTY) {
2772                 return parse_attribute_ms_property(attribute);
2773         }
2774
2775         /* parse arguments */
2776         if (next_if('('))
2777                 attribute->a.arguments = parse_attribute_arguments();
2778
2779         return attribute;
2780 }
2781
2782 static attribute_t *parse_microsoft_extended_decl_modifier(attribute_t *first)
2783 {
2784         eat(T__declspec);
2785
2786         expect('(', end_error);
2787
2788         if (next_if(')'))
2789                 return NULL;
2790
2791         add_anchor_token(')');
2792
2793         attribute_t **anchor = &first;
2794         do {
2795                 while (*anchor != NULL)
2796                         anchor = &(*anchor)->next;
2797
2798                 attribute_t *attribute
2799                         = parse_microsoft_extended_decl_modifier_single();
2800                 if (attribute == NULL)
2801                         goto end_error;
2802
2803                 *anchor = attribute;
2804                 anchor  = &attribute->next;
2805         } while (next_if(','));
2806
2807         rem_anchor_token(')');
2808         expect(')', end_error);
2809         return first;
2810
2811 end_error:
2812         rem_anchor_token(')');
2813         return first;
2814 }
2815
2816 static entity_t *create_error_entity(symbol_t *symbol, entity_kind_tag_t kind)
2817 {
2818         entity_t *entity             = allocate_entity_zero(kind);
2819         entity->base.namespc         = NAMESPACE_NORMAL;
2820         entity->base.source_position = *HERE;
2821         entity->base.symbol          = symbol;
2822         if (is_declaration(entity)) {
2823                 entity->declaration.type     = type_error_type;
2824                 entity->declaration.implicit = true;
2825         } else if (kind == ENTITY_TYPEDEF) {
2826                 entity->typedefe.type    = type_error_type;
2827                 entity->typedefe.builtin = true;
2828         }
2829         if (kind != ENTITY_COMPOUND_MEMBER)
2830                 record_entity(entity, false);
2831         return entity;
2832 }
2833
2834 static void parse_declaration_specifiers(declaration_specifiers_t *specifiers)
2835 {
2836         type_t            *type              = NULL;
2837         type_qualifiers_t  qualifiers        = TYPE_QUALIFIER_NONE;
2838         unsigned           type_specifiers   = 0;
2839         bool               newtype           = false;
2840         bool               saw_error         = false;
2841         bool               old_gcc_extension = in_gcc_extension;
2842
2843         specifiers->source_position = token.source_position;
2844
2845         while (true) {
2846                 specifiers->attributes = parse_attributes(specifiers->attributes);
2847
2848                 switch (token.type) {
2849                 /* storage class */
2850 #define MATCH_STORAGE_CLASS(token, class)                                  \
2851                 case token:                                                        \
2852                         if (specifiers->storage_class != STORAGE_CLASS_NONE) {         \
2853                                 errorf(HERE, "multiple storage classes in declaration specifiers"); \
2854                         }                                                              \
2855                         specifiers->storage_class = class;                             \
2856                         if (specifiers->thread_local)                                  \
2857                                 goto check_thread_storage_class;                           \
2858                         next_token();                                                  \
2859                         break;
2860
2861                 MATCH_STORAGE_CLASS(T_typedef,  STORAGE_CLASS_TYPEDEF)
2862                 MATCH_STORAGE_CLASS(T_extern,   STORAGE_CLASS_EXTERN)
2863                 MATCH_STORAGE_CLASS(T_static,   STORAGE_CLASS_STATIC)
2864                 MATCH_STORAGE_CLASS(T_auto,     STORAGE_CLASS_AUTO)
2865                 MATCH_STORAGE_CLASS(T_register, STORAGE_CLASS_REGISTER)
2866
2867                 case T__declspec:
2868                         specifiers->attributes
2869                                 = parse_microsoft_extended_decl_modifier(specifiers->attributes);
2870                         break;
2871
2872                 case T___thread:
2873                         if (specifiers->thread_local) {
2874                                 errorf(HERE, "duplicate '__thread'");
2875                         } else {
2876                                 specifiers->thread_local = true;
2877 check_thread_storage_class:
2878                                 switch (specifiers->storage_class) {
2879                                         case STORAGE_CLASS_EXTERN:
2880                                         case STORAGE_CLASS_NONE:
2881                                         case STORAGE_CLASS_STATIC:
2882                                                 break;
2883
2884                                                 char const* wrong;
2885                                         case STORAGE_CLASS_AUTO:     wrong = "auto";     goto wrong_thread_storage_class;
2886                                         case STORAGE_CLASS_REGISTER: wrong = "register"; goto wrong_thread_storage_class;
2887                                         case STORAGE_CLASS_TYPEDEF:  wrong = "typedef";  goto wrong_thread_storage_class;
2888 wrong_thread_storage_class:
2889                                                 errorf(HERE, "'__thread' used with '%s'", wrong);
2890                                                 break;
2891                                 }
2892                         }
2893                         next_token();
2894                         break;
2895
2896                 /* type qualifiers */
2897 #define MATCH_TYPE_QUALIFIER(token, qualifier)                          \
2898                 case token:                                                     \
2899                         qualifiers |= qualifier;                                    \
2900                         next_token();                                               \
2901                         break
2902
2903                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
2904                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
2905                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
2906                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
2907                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
2908                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
2909                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
2910                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
2911
2912                 case T___extension__:
2913                         next_token();
2914                         in_gcc_extension = true;
2915                         break;
2916
2917                 /* type specifiers */
2918 #define MATCH_SPECIFIER(token, specifier, name)                         \
2919                 case token:                                                     \
2920                         if (type_specifiers & specifier) {                           \
2921                                 errorf(HERE, "multiple " name " type specifiers given"); \
2922                         } else {                                                    \
2923                                 type_specifiers |= specifier;                           \
2924                         }                                                           \
2925                         next_token();                                               \
2926                         break
2927
2928                 MATCH_SPECIFIER(T__Bool,      SPECIFIER_BOOL,      "_Bool");
2929                 MATCH_SPECIFIER(T__Complex,   SPECIFIER_COMPLEX,   "_Complex");
2930                 MATCH_SPECIFIER(T__Imaginary, SPECIFIER_IMAGINARY, "_Imaginary");
2931                 MATCH_SPECIFIER(T__int128,    SPECIFIER_INT128,    "_int128");
2932                 MATCH_SPECIFIER(T__int16,     SPECIFIER_INT16,     "_int16");
2933                 MATCH_SPECIFIER(T__int32,     SPECIFIER_INT32,     "_int32");
2934                 MATCH_SPECIFIER(T__int64,     SPECIFIER_INT64,     "_int64");
2935                 MATCH_SPECIFIER(T__int8,      SPECIFIER_INT8,      "_int8");
2936                 MATCH_SPECIFIER(T_bool,       SPECIFIER_BOOL,      "bool");
2937                 MATCH_SPECIFIER(T_char,       SPECIFIER_CHAR,      "char");
2938                 MATCH_SPECIFIER(T_double,     SPECIFIER_DOUBLE,    "double");
2939                 MATCH_SPECIFIER(T_float,      SPECIFIER_FLOAT,     "float");
2940                 MATCH_SPECIFIER(T_int,        SPECIFIER_INT,       "int");
2941                 MATCH_SPECIFIER(T_short,      SPECIFIER_SHORT,     "short");
2942                 MATCH_SPECIFIER(T_signed,     SPECIFIER_SIGNED,    "signed");
2943                 MATCH_SPECIFIER(T_unsigned,   SPECIFIER_UNSIGNED,  "unsigned");
2944                 MATCH_SPECIFIER(T_void,       SPECIFIER_VOID,      "void");
2945                 MATCH_SPECIFIER(T_wchar_t,    SPECIFIER_WCHAR_T,   "wchar_t");
2946
2947                 case T_inline:
2948                         next_token();
2949                         specifiers->is_inline = true;
2950                         break;
2951
2952 #if 0
2953                 case T__forceinline:
2954                         next_token();
2955                         specifiers->modifiers |= DM_FORCEINLINE;
2956                         break;
2957 #endif
2958
2959                 case T_long:
2960                         if (type_specifiers & SPECIFIER_LONG_LONG) {
2961                                 errorf(HERE, "multiple type specifiers given");
2962                         } else if (type_specifiers & SPECIFIER_LONG) {
2963                                 type_specifiers |= SPECIFIER_LONG_LONG;
2964                         } else {
2965                                 type_specifiers |= SPECIFIER_LONG;
2966                         }
2967                         next_token();
2968                         break;
2969
2970 #define CHECK_DOUBLE_TYPE()        \
2971                         if ( type != NULL)     \
2972                                 errorf(HERE, "multiple data types in declaration specifiers");
2973
2974                 case T_struct:
2975                         CHECK_DOUBLE_TYPE();
2976                         type = allocate_type_zero(TYPE_COMPOUND_STRUCT);
2977
2978                         type->compound.compound = parse_compound_type_specifier(true);
2979                         break;
2980                 case T_union:
2981                         CHECK_DOUBLE_TYPE();
2982                         type = allocate_type_zero(TYPE_COMPOUND_UNION);
2983                         type->compound.compound = parse_compound_type_specifier(false);
2984                         break;
2985                 case T_enum:
2986                         CHECK_DOUBLE_TYPE();
2987                         type = parse_enum_specifier();
2988                         break;
2989                 case T___typeof__:
2990                         CHECK_DOUBLE_TYPE();
2991                         type = parse_typeof();
2992                         break;
2993                 case T___builtin_va_list:
2994                         CHECK_DOUBLE_TYPE();
2995                         type = duplicate_type(type_valist);
2996                         next_token();
2997                         break;
2998
2999                 case T_IDENTIFIER: {
3000                         /* only parse identifier if we haven't found a type yet */
3001                         if (type != NULL || type_specifiers != 0) {
3002                                 /* Be somewhat resilient to typos like 'unsigned lng* f()' in a
3003                                  * declaration, so it doesn't generate errors about expecting '(' or
3004                                  * '{' later on. */
3005                                 switch (look_ahead(1)->type) {
3006                                         STORAGE_CLASSES
3007                                         TYPE_SPECIFIERS
3008                                         case T_const:
3009                                         case T_restrict:
3010                                         case T_volatile:
3011                                         case T_inline:
3012                                         case T__forceinline: /* ^ DECLARATION_START except for __attribute__ */
3013                                         case T_IDENTIFIER:
3014                                         case '&':
3015                                         case '*':
3016                                                 errorf(HERE, "discarding stray %K in declaration specifier", &token);
3017                                                 next_token();
3018                                                 continue;
3019
3020                                         default:
3021                                                 goto finish_specifiers;
3022                                 }
3023                         }
3024
3025                         type_t *const typedef_type = get_typedef_type(token.symbol);
3026                         if (typedef_type == NULL) {
3027                                 /* Be somewhat resilient to typos like 'vodi f()' at the beginning of a
3028                                  * declaration, so it doesn't generate 'implicit int' followed by more
3029                                  * errors later on. */
3030                                 token_type_t const la1_type = (token_type_t)look_ahead(1)->type;
3031                                 switch (la1_type) {
3032                                         DECLARATION_START
3033                                         case T_IDENTIFIER:
3034                                         case '&':
3035                                         case '*': {
3036                                                 errorf(HERE, "%K does not name a type", &token);
3037
3038                                                 entity_t *entity =
3039                                                         create_error_entity(token.symbol, ENTITY_TYPEDEF);
3040
3041                                                 type = allocate_type_zero(TYPE_TYPEDEF);
3042                                                 type->typedeft.typedefe = &entity->typedefe;
3043
3044                                                 next_token();
3045                                                 saw_error = true;
3046                                                 if (la1_type == '&' || la1_type == '*')
3047                                                         goto finish_specifiers;
3048                                                 continue;
3049                                         }
3050
3051                                         default:
3052                                                 goto finish_specifiers;
3053                                 }
3054                         }
3055
3056                         next_token();
3057                         type = typedef_type;
3058                         break;
3059                 }
3060
3061                 /* function specifier */
3062                 default:
3063                         goto finish_specifiers;
3064                 }
3065         }
3066
3067 finish_specifiers:
3068         specifiers->attributes = parse_attributes(specifiers->attributes);
3069
3070         in_gcc_extension = old_gcc_extension;
3071
3072         if (type == NULL || (saw_error && type_specifiers != 0)) {
3073                 atomic_type_kind_t atomic_type;
3074
3075                 /* match valid basic types */
3076                 switch (type_specifiers) {
3077                 case SPECIFIER_VOID:
3078                         atomic_type = ATOMIC_TYPE_VOID;
3079                         break;
3080                 case SPECIFIER_WCHAR_T:
3081                         atomic_type = ATOMIC_TYPE_WCHAR_T;
3082                         break;
3083                 case SPECIFIER_CHAR:
3084                         atomic_type = ATOMIC_TYPE_CHAR;
3085                         break;
3086                 case SPECIFIER_SIGNED | SPECIFIER_CHAR:
3087                         atomic_type = ATOMIC_TYPE_SCHAR;
3088                         break;
3089                 case SPECIFIER_UNSIGNED | SPECIFIER_CHAR:
3090                         atomic_type = ATOMIC_TYPE_UCHAR;
3091                         break;
3092                 case SPECIFIER_SHORT:
3093                 case SPECIFIER_SIGNED | SPECIFIER_SHORT:
3094                 case SPECIFIER_SHORT | SPECIFIER_INT:
3095                 case SPECIFIER_SIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3096                         atomic_type = ATOMIC_TYPE_SHORT;
3097                         break;
3098                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT:
3099                 case SPECIFIER_UNSIGNED | SPECIFIER_SHORT | SPECIFIER_INT:
3100                         atomic_type = ATOMIC_TYPE_USHORT;
3101                         break;
3102                 case SPECIFIER_INT:
3103                 case SPECIFIER_SIGNED:
3104                 case SPECIFIER_SIGNED | SPECIFIER_INT:
3105                         atomic_type = ATOMIC_TYPE_INT;
3106                         break;
3107                 case SPECIFIER_UNSIGNED:
3108                 case SPECIFIER_UNSIGNED | SPECIFIER_INT:
3109                         atomic_type = ATOMIC_TYPE_UINT;
3110                         break;
3111                 case SPECIFIER_LONG:
3112                 case SPECIFIER_SIGNED | SPECIFIER_LONG:
3113                 case SPECIFIER_LONG | SPECIFIER_INT:
3114                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3115                         atomic_type = ATOMIC_TYPE_LONG;
3116                         break;
3117                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG:
3118                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_INT:
3119                         atomic_type = ATOMIC_TYPE_ULONG;
3120                         break;
3121
3122                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3123                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3124                 case SPECIFIER_LONG | SPECIFIER_LONG_LONG | SPECIFIER_INT:
3125                 case SPECIFIER_SIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3126                         | SPECIFIER_INT:
3127                         atomic_type = ATOMIC_TYPE_LONGLONG;
3128                         goto warn_about_long_long;
3129
3130                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG:
3131                 case SPECIFIER_UNSIGNED | SPECIFIER_LONG | SPECIFIER_LONG_LONG
3132                         | SPECIFIER_INT:
3133                         atomic_type = ATOMIC_TYPE_ULONGLONG;
3134 warn_about_long_long:
3135                         if (warning.long_long) {
3136                                 warningf(&specifiers->source_position,
3137                                          "ISO C90 does not support 'long long'");
3138                         }
3139                         break;
3140
3141                 case SPECIFIER_UNSIGNED | SPECIFIER_INT8:
3142                         atomic_type = unsigned_int8_type_kind;
3143                         break;
3144
3145                 case SPECIFIER_UNSIGNED | SPECIFIER_INT16:
3146                         atomic_type = unsigned_int16_type_kind;
3147                         break;
3148
3149                 case SPECIFIER_UNSIGNED | SPECIFIER_INT32:
3150                         atomic_type = unsigned_int32_type_kind;
3151                         break;
3152
3153                 case SPECIFIER_UNSIGNED | SPECIFIER_INT64:
3154                         atomic_type = unsigned_int64_type_kind;
3155                         break;
3156
3157                 case SPECIFIER_UNSIGNED | SPECIFIER_INT128:
3158                         atomic_type = unsigned_int128_type_kind;
3159                         break;
3160
3161                 case SPECIFIER_INT8:
3162                 case SPECIFIER_SIGNED | SPECIFIER_INT8:
3163                         atomic_type = int8_type_kind;
3164                         break;
3165
3166                 case SPECIFIER_INT16:
3167                 case SPECIFIER_SIGNED | SPECIFIER_INT16:
3168                         atomic_type = int16_type_kind;
3169                         break;
3170
3171                 case SPECIFIER_INT32:
3172                 case SPECIFIER_SIGNED | SPECIFIER_INT32:
3173                         atomic_type = int32_type_kind;
3174                         break;
3175
3176                 case SPECIFIER_INT64:
3177                 case SPECIFIER_SIGNED | SPECIFIER_INT64:
3178                         atomic_type = int64_type_kind;
3179                         break;
3180
3181                 case SPECIFIER_INT128:
3182                 case SPECIFIER_SIGNED | SPECIFIER_INT128:
3183                         atomic_type = int128_type_kind;
3184                         break;
3185
3186                 case SPECIFIER_FLOAT:
3187                         atomic_type = ATOMIC_TYPE_FLOAT;
3188                         break;
3189                 case SPECIFIER_DOUBLE:
3190                         atomic_type = ATOMIC_TYPE_DOUBLE;
3191                         break;
3192                 case SPECIFIER_LONG | SPECIFIER_DOUBLE:
3193                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3194                         break;
3195                 case SPECIFIER_BOOL:
3196                         atomic_type = ATOMIC_TYPE_BOOL;
3197                         break;
3198                 case SPECIFIER_FLOAT | SPECIFIER_COMPLEX:
3199                 case SPECIFIER_FLOAT | SPECIFIER_IMAGINARY:
3200                         atomic_type = ATOMIC_TYPE_FLOAT;
3201                         break;
3202                 case SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3203                 case SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3204                         atomic_type = ATOMIC_TYPE_DOUBLE;
3205                         break;
3206                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_COMPLEX:
3207                 case SPECIFIER_LONG | SPECIFIER_DOUBLE | SPECIFIER_IMAGINARY:
3208                         atomic_type = ATOMIC_TYPE_LONG_DOUBLE;
3209                         break;
3210                 default:
3211                         /* invalid specifier combination, give an error message */
3212                         if (type_specifiers == 0) {
3213                                 if (saw_error)
3214                                         goto end_error;
3215
3216                                 /* ISO/IEC 14882:1998(E) §C.1.5:4 */
3217                                 if (!(c_mode & _CXX) && !strict_mode) {
3218                                         if (warning.implicit_int) {
3219                                                 warningf(HERE, "no type specifiers in declaration, using 'int'");
3220                                         }
3221                                         atomic_type = ATOMIC_TYPE_INT;
3222                                         break;
3223                                 } else {
3224                                         errorf(HERE, "no type specifiers given in declaration");
3225                                 }
3226                         } else if ((type_specifiers & SPECIFIER_SIGNED) &&
3227                                   (type_specifiers & SPECIFIER_UNSIGNED)) {
3228                                 errorf(HERE, "signed and unsigned specifiers given");
3229                         } else if (type_specifiers & (SPECIFIER_SIGNED | SPECIFIER_UNSIGNED)) {
3230                                 errorf(HERE, "only integer types can be signed or unsigned");
3231                         } else {
3232                                 errorf(HERE, "multiple datatypes in declaration");
3233                         }
3234                         goto end_error;
3235                 }
3236
3237                 if (type_specifiers & SPECIFIER_COMPLEX) {
3238                         type                = allocate_type_zero(TYPE_COMPLEX);
3239                         type->complex.akind = atomic_type;
3240                 } else if (type_specifiers & SPECIFIER_IMAGINARY) {
3241                         type                  = allocate_type_zero(TYPE_IMAGINARY);
3242                         type->imaginary.akind = atomic_type;
3243                 } else {
3244                         type                 = allocate_type_zero(TYPE_ATOMIC);
3245                         type->atomic.akind   = atomic_type;
3246                 }
3247                 newtype = true;
3248         } else if (type_specifiers != 0) {
3249                 errorf(HERE, "multiple datatypes in declaration");
3250         }
3251
3252         /* FIXME: check type qualifiers here */
3253         type->base.qualifiers = qualifiers;
3254
3255         if (newtype) {
3256                 type = identify_new_type(type);
3257         } else {
3258                 type = typehash_insert(type);
3259         }
3260
3261         if (specifiers->attributes != NULL)
3262                 type = handle_type_attributes(specifiers->attributes, type);
3263         specifiers->type = type;
3264         return;
3265
3266 end_error:
3267         specifiers->type = type_error_type;
3268 }
3269
3270 static type_qualifiers_t parse_type_qualifiers(void)
3271 {
3272         type_qualifiers_t qualifiers = TYPE_QUALIFIER_NONE;
3273
3274         while (true) {
3275                 switch (token.type) {
3276                 /* type qualifiers */
3277                 MATCH_TYPE_QUALIFIER(T_const,    TYPE_QUALIFIER_CONST);
3278                 MATCH_TYPE_QUALIFIER(T_restrict, TYPE_QUALIFIER_RESTRICT);
3279                 MATCH_TYPE_QUALIFIER(T_volatile, TYPE_QUALIFIER_VOLATILE);
3280                 /* microsoft extended type modifiers */
3281                 MATCH_TYPE_QUALIFIER(T__w64,     TYPE_QUALIFIER_W64);
3282                 MATCH_TYPE_QUALIFIER(T___ptr32,  TYPE_QUALIFIER_PTR32);
3283                 MATCH_TYPE_QUALIFIER(T___ptr64,  TYPE_QUALIFIER_PTR64);
3284                 MATCH_TYPE_QUALIFIER(T___uptr,   TYPE_QUALIFIER_UPTR);
3285                 MATCH_TYPE_QUALIFIER(T___sptr,   TYPE_QUALIFIER_SPTR);
3286
3287                 default:
3288                         return qualifiers;
3289                 }
3290         }
3291 }
3292
3293 /**
3294  * Parses an K&R identifier list
3295  */
3296 static void parse_identifier_list(scope_t *scope)
3297 {
3298         do {
3299                 entity_t *entity = allocate_entity_zero(ENTITY_PARAMETER);
3300                 entity->base.source_position = token.source_position;
3301                 entity->base.namespc         = NAMESPACE_NORMAL;
3302                 entity->base.symbol          = token.symbol;
3303                 /* a K&R parameter has no type, yet */
3304                 next_token();
3305
3306                 if (scope != NULL)
3307                         append_entity(scope, entity);
3308         } while (next_if(',') && token.type == T_IDENTIFIER);
3309 }
3310
3311 static entity_t *parse_parameter(void)
3312 {
3313         declaration_specifiers_t specifiers;
3314         memset(&specifiers, 0, sizeof(specifiers));
3315
3316         parse_declaration_specifiers(&specifiers);
3317
3318         entity_t *entity = parse_declarator(&specifiers,
3319                         DECL_MAY_BE_ABSTRACT | DECL_IS_PARAMETER);
3320         anonymous_entity = NULL;
3321         return entity;
3322 }
3323
3324 static void semantic_parameter_incomplete(const entity_t *entity)
3325 {
3326         assert(entity->kind == ENTITY_PARAMETER);
3327
3328         /* §6.7.5.3:4  After adjustment, the parameters in a parameter type
3329          *             list in a function declarator that is part of a
3330          *             definition of that function shall not have
3331          *             incomplete type. */
3332         type_t *type = skip_typeref(entity->declaration.type);
3333         if (is_type_incomplete(type)) {
3334                 errorf(&entity->base.source_position,
3335                                 "parameter '%#T' has incomplete type",
3336                                 entity->declaration.type, entity->base.symbol);
3337         }
3338 }
3339
3340 static bool has_parameters(void)
3341 {
3342         /* func(void) is not a parameter */
3343         if (token.type == T_IDENTIFIER) {
3344                 entity_t const *const entity = get_entity(token.symbol, NAMESPACE_NORMAL);
3345                 if (entity == NULL)
3346                         return true;
3347                 if (entity->kind != ENTITY_TYPEDEF)
3348                         return true;
3349                 if (skip_typeref(entity->typedefe.type) != type_void)
3350                         return true;
3351         } else if (token.type != T_void) {
3352                 return true;
3353         }
3354         if (look_ahead(1)->type != ')')
3355                 return true;
3356         next_token();
3357         return false;
3358 }
3359
3360 /**
3361  * Parses function type parameters (and optionally creates variable_t entities
3362  * for them in a scope)
3363  */
3364 static void parse_parameters(function_type_t *type, scope_t *scope)
3365 {
3366         eat('(');
3367         add_anchor_token(')');
3368         int saved_comma_state = save_and_reset_anchor_state(',');
3369
3370         if (token.type == T_IDENTIFIER &&
3371             !is_typedef_symbol(token.symbol)) {
3372                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
3373                 if (la1_type == ',' || la1_type == ')') {
3374                         type->kr_style_parameters = true;
3375                         parse_identifier_list(scope);
3376                         goto parameters_finished;
3377                 }
3378         }
3379
3380         if (token.type == ')') {
3381                 /* ISO/IEC 14882:1998(E) §C.1.6:1 */
3382                 if (!(c_mode & _CXX))
3383                         type->unspecified_parameters = true;
3384                 goto parameters_finished;
3385         }
3386
3387         if (has_parameters()) {
3388                 function_parameter_t **anchor = &type->parameters;
3389                 do {
3390                         switch (token.type) {
3391                         case T_DOTDOTDOT:
3392                                 next_token();
3393                                 type->variadic = true;
3394                                 goto parameters_finished;
3395
3396                         case T_IDENTIFIER:
3397                         case T___extension__:
3398                         DECLARATION_START
3399                         {
3400                                 entity_t *entity = parse_parameter();
3401                                 if (entity->kind == ENTITY_TYPEDEF) {
3402                                         errorf(&entity->base.source_position,
3403                                                         "typedef not allowed as function parameter");
3404                                         break;
3405                                 }
3406                                 assert(is_declaration(entity));
3407
3408                                 semantic_parameter_incomplete(entity);
3409
3410                                 function_parameter_t *const parameter =
3411                                         allocate_parameter(entity->declaration.type);
3412
3413                                 if (scope != NULL) {
3414                                         append_entity(scope, entity);
3415                                 }
3416
3417                                 *anchor = parameter;
3418                                 anchor  = &parameter->next;
3419                                 break;
3420                         }
3421
3422                         default:
3423                                 goto parameters_finished;
3424                         }
3425                 } while (next_if(','));
3426         }
3427
3428
3429 parameters_finished:
3430         rem_anchor_token(')');
3431         expect(')', end_error);
3432
3433 end_error:
3434         restore_anchor_state(',', saved_comma_state);
3435 }
3436
3437 typedef enum construct_type_kind_t {
3438         CONSTRUCT_INVALID,
3439         CONSTRUCT_POINTER,
3440         CONSTRUCT_REFERENCE,
3441         CONSTRUCT_FUNCTION,
3442         CONSTRUCT_ARRAY
3443 } construct_type_kind_t;
3444
3445 typedef union construct_type_t construct_type_t;
3446
3447 typedef struct construct_type_base_t {
3448         construct_type_kind_t  kind;
3449         source_position_t      pos;
3450         construct_type_t      *next;
3451 } construct_type_base_t;
3452
3453 typedef struct parsed_pointer_t {
3454         construct_type_base_t  base;
3455         type_qualifiers_t      type_qualifiers;
3456         variable_t            *base_variable;  /**< MS __based extension. */
3457 } parsed_pointer_t;
3458
3459 typedef struct parsed_reference_t {
3460         construct_type_base_t base;
3461 } parsed_reference_t;
3462
3463 typedef struct construct_function_type_t {
3464         construct_type_base_t  base;
3465         type_t                *function_type;
3466 } construct_function_type_t;
3467
3468 typedef struct parsed_array_t {
3469         construct_type_base_t  base;
3470         type_qualifiers_t      type_qualifiers;
3471         bool                   is_static;
3472         bool                   is_variable;
3473         expression_t          *size;
3474 } parsed_array_t;
3475
3476 union construct_type_t {
3477         construct_type_kind_t     kind;
3478         construct_type_base_t     base;
3479         parsed_pointer_t          pointer;
3480         parsed_reference_t        reference;
3481         construct_function_type_t function;
3482         parsed_array_t            array;
3483 };
3484
3485 static construct_type_t *allocate_declarator_zero(construct_type_kind_t const kind, size_t const size)
3486 {
3487         construct_type_t *const cons = obstack_alloc(&temp_obst, size);
3488         memset(cons, 0, size);
3489         cons->kind     = kind;
3490         cons->base.pos = *HERE;
3491         return cons;
3492 }
3493
3494 /* §6.7.5.1 */
3495 static construct_type_t *parse_pointer_declarator(void)
3496 {
3497         construct_type_t *const cons = allocate_declarator_zero(CONSTRUCT_POINTER, sizeof(parsed_pointer_t));
3498         eat('*');
3499         cons->pointer.type_qualifiers = parse_type_qualifiers();
3500         //cons->pointer.base_variable   = base_variable;
3501
3502         return cons;
3503 }
3504
3505 /* ISO/IEC 14882:1998(E) §8.3.2 */
3506 static construct_type_t *parse_reference_declarator(void)
3507 {
3508         if (!(c_mode & _CXX))
3509                 errorf(HERE, "references are only available for C++");
3510
3511         construct_type_t *const cons = allocate_declarator_zero(CONSTRUCT_REFERENCE, sizeof(parsed_reference_t));
3512         eat('&');
3513
3514         return cons;
3515 }
3516
3517 /* §6.7.5.2 */
3518 static construct_type_t *parse_array_declarator(void)
3519 {
3520         construct_type_t *const cons  = allocate_declarator_zero(CONSTRUCT_ARRAY, sizeof(parsed_array_t));
3521         parsed_array_t   *const array = &cons->array;
3522
3523         eat('[');
3524         add_anchor_token(']');
3525
3526         bool is_static = next_if(T_static);
3527
3528         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
3529
3530         if (!is_static)
3531                 is_static = next_if(T_static);
3532
3533         array->type_qualifiers = type_qualifiers;
3534         array->is_static       = is_static;
3535
3536         expression_t *size = NULL;
3537         if (token.type == '*' && look_ahead(1)->type == ']') {
3538                 array->is_variable = true;
3539                 next_token();
3540         } else if (token.type != ']') {
3541                 size = parse_assignment_expression();
3542
3543                 /* §6.7.5.2:1  Array size must have integer type */
3544                 type_t *const orig_type = size->base.type;
3545                 type_t *const type      = skip_typeref(orig_type);
3546                 if (!is_type_integer(type) && is_type_valid(type)) {
3547                         errorf(&size->base.source_position,
3548                                "array size '%E' must have integer type but has type '%T'",
3549                                size, orig_type);
3550                 }
3551
3552                 array->size = size;
3553                 mark_vars_read(size, NULL);
3554         }
3555
3556         if (is_static && size == NULL)
3557                 errorf(HERE, "static array parameters require a size");
3558
3559         rem_anchor_token(']');
3560         expect(']', end_error);
3561
3562 end_error:
3563         return cons;
3564 }
3565
3566 /* §6.7.5.3 */
3567 static construct_type_t *parse_function_declarator(scope_t *scope)
3568 {
3569         construct_type_t *const cons = allocate_declarator_zero(CONSTRUCT_FUNCTION, sizeof(construct_function_type_t));
3570
3571         type_t          *type  = allocate_type_zero(TYPE_FUNCTION);
3572         function_type_t *ftype = &type->function;
3573
3574         ftype->linkage            = current_linkage;
3575         ftype->calling_convention = CC_DEFAULT;
3576
3577         parse_parameters(ftype, scope);
3578
3579         cons->function.function_type = type;
3580
3581         return cons;
3582 }
3583
3584 typedef struct parse_declarator_env_t {
3585         bool               may_be_abstract : 1;
3586         bool               must_be_abstract : 1;
3587         decl_modifiers_t   modifiers;
3588         symbol_t          *symbol;
3589         source_position_t  source_position;
3590         scope_t            parameters;
3591         attribute_t       *attributes;
3592 } parse_declarator_env_t;
3593
3594 /* §6.7.5 */
3595 static construct_type_t *parse_inner_declarator(parse_declarator_env_t *env)
3596 {
3597         /* construct a single linked list of construct_type_t's which describe
3598          * how to construct the final declarator type */
3599         construct_type_t  *first      = NULL;
3600         construct_type_t **anchor     = &first;
3601
3602         env->attributes = parse_attributes(env->attributes);
3603
3604         for (;;) {
3605                 construct_type_t *type;
3606                 //variable_t       *based = NULL; /* MS __based extension */
3607                 switch (token.type) {
3608                         case '&':
3609                                 type = parse_reference_declarator();
3610                                 break;
3611
3612                         case T__based: {
3613                                 panic("based not supported anymore");
3614                                 /* FALLTHROUGH */
3615                         }
3616
3617                         case '*':
3618                                 type = parse_pointer_declarator();
3619                                 break;
3620
3621                         default:
3622                                 goto ptr_operator_end;
3623                 }
3624
3625                 *anchor = type;
3626                 anchor  = &type->base.next;
3627
3628                 /* TODO: find out if this is correct */
3629                 env->attributes = parse_attributes(env->attributes);
3630         }
3631
3632 ptr_operator_end: ;
3633         construct_type_t *inner_types = NULL;
3634
3635         switch (token.type) {
3636         case T_IDENTIFIER:
3637                 if (env->must_be_abstract) {
3638                         errorf(HERE, "no identifier expected in typename");
3639                 } else {
3640                         env->symbol          = token.symbol;
3641                         env->source_position = token.source_position;
3642                 }
3643                 next_token();
3644                 break;
3645         case '(':
3646                 /* §6.7.6:2 footnote 126:  Empty parentheses in a type name are
3647                  * interpreted as ``function with no parameter specification'', rather
3648                  * than redundant parentheses around the omitted identifier. */
3649                 if (look_ahead(1)->type != ')') {
3650                         next_token();
3651                         add_anchor_token(')');
3652                         inner_types = parse_inner_declarator(env);
3653                         if (inner_types != NULL) {
3654                                 /* All later declarators only modify the return type */
3655                                 env->must_be_abstract = true;
3656                         }
3657                         rem_anchor_token(')');
3658                         expect(')', end_error);
3659                 } else if (!env->may_be_abstract) {
3660                         errorf(HERE, "declarator must have a name");
3661                         goto error_out;
3662                 }
3663                 break;
3664         default:
3665                 if (env->may_be_abstract)
3666                         break;
3667                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
3668 error_out:
3669                 eat_until_anchor();
3670                 return NULL;
3671         }
3672
3673         construct_type_t **const p = anchor;
3674
3675         for (;;) {
3676                 construct_type_t *type;
3677                 switch (token.type) {
3678                 case '(': {
3679                         scope_t *scope = NULL;
3680                         if (!env->must_be_abstract) {
3681                                 scope = &env->parameters;
3682                         }
3683
3684                         type = parse_function_declarator(scope);
3685                         break;
3686                 }
3687                 case '[':
3688                         type = parse_array_declarator();
3689                         break;
3690                 default:
3691                         goto declarator_finished;
3692                 }
3693
3694                 /* insert in the middle of the list (at p) */
3695                 type->base.next = *p;
3696                 *p              = type;
3697                 if (anchor == p)
3698                         anchor = &type->base.next;
3699         }
3700
3701 declarator_finished:
3702         /* append inner_types at the end of the list, we don't to set anchor anymore
3703          * as it's not needed anymore */
3704         *anchor = inner_types;
3705
3706         return first;
3707 end_error:
3708         return NULL;
3709 }
3710
3711 static type_t *construct_declarator_type(construct_type_t *construct_list,
3712                                          type_t *type)
3713 {
3714         construct_type_t *iter = construct_list;
3715         for (; iter != NULL; iter = iter->base.next) {
3716                 source_position_t const* const pos = &iter->base.pos;
3717                 switch (iter->kind) {
3718                 case CONSTRUCT_INVALID:
3719                         break;
3720                 case CONSTRUCT_FUNCTION: {
3721                         construct_function_type_t *function      = &iter->function;
3722                         type_t                    *function_type = function->function_type;
3723
3724                         function_type->function.return_type = type;
3725
3726                         type_t *skipped_return_type = skip_typeref(type);
3727                         /* §6.7.5.3:1 */
3728                         if (is_type_function(skipped_return_type)) {
3729                                 errorf(pos, "function returning function is not allowed");
3730                         } else if (is_type_array(skipped_return_type)) {
3731                                 errorf(pos, "function returning array is not allowed");
3732                         } else {
3733                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
3734                                         warningf(pos, "type qualifiers in return type of function type are meaningless");
3735                                 }
3736                         }
3737
3738                         /* The function type was constructed earlier.  Freeing it here will
3739                          * destroy other types. */
3740                         type = typehash_insert(function_type);
3741                         continue;
3742                 }
3743
3744                 case CONSTRUCT_POINTER: {
3745                         if (is_type_reference(skip_typeref(type)))
3746                                 errorf(pos, "cannot declare a pointer to reference");
3747
3748                         parsed_pointer_t *pointer = &iter->pointer;
3749                         type = make_based_pointer_type(type, pointer->type_qualifiers, pointer->base_variable);
3750                         continue;
3751                 }
3752
3753                 case CONSTRUCT_REFERENCE:
3754                         if (is_type_reference(skip_typeref(type)))
3755                                 errorf(pos, "cannot declare a reference to reference");
3756
3757                         type = make_reference_type(type);
3758                         continue;
3759
3760                 case CONSTRUCT_ARRAY: {
3761                         if (is_type_reference(skip_typeref(type)))
3762                                 errorf(pos, "cannot declare an array of references");
3763
3764                         parsed_array_t *array      = &iter->array;
3765                         type_t         *array_type = allocate_type_zero(TYPE_ARRAY);
3766
3767                         expression_t *size_expression = array->size;
3768                         if (size_expression != NULL) {
3769                                 size_expression
3770                                         = create_implicit_cast(size_expression, type_size_t);
3771                         }
3772
3773                         array_type->base.qualifiers       = array->type_qualifiers;
3774                         array_type->array.element_type    = type;
3775                         array_type->array.is_static       = array->is_static;
3776                         array_type->array.is_variable     = array->is_variable;
3777                         array_type->array.size_expression = size_expression;
3778
3779                         if (size_expression != NULL) {
3780                                 switch (is_constant_expression(size_expression)) {
3781                                         case EXPR_CLASS_CONSTANT: {
3782                                                 long const size = fold_constant_to_int(size_expression);
3783                                                 array_type->array.size          = size;
3784                                                 array_type->array.size_constant = true;
3785                                                 /* §6.7.5.2:1  If the expression is a constant expression, it shall
3786                                                  * have a value greater than zero. */
3787                                                 if (size <= 0) {
3788                                                         if (size < 0 || !GNU_MODE) {
3789                                                                 errorf(&size_expression->base.source_position,
3790                                                                                 "size of array must be greater than zero");
3791                                                         } else if (warning.other) {
3792                                                                 warningf(&size_expression->base.source_position,
3793                                                                                 "zero length arrays are a GCC extension");
3794                                                         }
3795                                                 }
3796                                                 break;
3797                                         }
3798
3799                                         case EXPR_CLASS_VARIABLE:
3800                                                 array_type->array.is_vla = true;
3801                                                 break;
3802
3803                                         case EXPR_CLASS_ERROR:
3804                                                 break;
3805                                 }
3806                         }
3807
3808                         type_t *skipped_type = skip_typeref(type);
3809                         /* §6.7.5.2:1 */
3810                         if (is_type_incomplete(skipped_type)) {
3811                                 errorf(pos, "array of incomplete type '%T' is not allowed", type);
3812                         } else if (is_type_function(skipped_type)) {
3813                                 errorf(pos, "array of functions is not allowed");
3814                         }
3815                         type = identify_new_type(array_type);
3816                         continue;
3817                 }
3818                 }
3819                 internal_errorf(pos, "invalid type construction found");
3820         }
3821
3822         return type;
3823 }
3824
3825 static type_t *automatic_type_conversion(type_t *orig_type);
3826
3827 static type_t *semantic_parameter(const source_position_t *pos,
3828                                   type_t *type,
3829                                   const declaration_specifiers_t *specifiers,
3830                                   symbol_t *symbol)
3831 {
3832         /* §6.7.5.3:7  A declaration of a parameter as ``array of type''
3833          *             shall be adjusted to ``qualified pointer to type'',
3834          *             [...]
3835          * §6.7.5.3:8  A declaration of a parameter as ``function returning
3836          *             type'' shall be adjusted to ``pointer to function
3837          *             returning type'', as in 6.3.2.1. */
3838         type = automatic_type_conversion(type);
3839
3840         if (specifiers->is_inline && is_type_valid(type)) {
3841                 errorf(pos, "parameter '%#T' declared 'inline'", type, symbol);
3842         }
3843
3844         /* §6.9.1:6  The declarations in the declaration list shall contain
3845          *           no storage-class specifier other than register and no
3846          *           initializations. */
3847         if (specifiers->thread_local || (
3848                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
3849                         specifiers->storage_class != STORAGE_CLASS_REGISTER)
3850            ) {
3851                 errorf(pos, "invalid storage class for parameter '%#T'", type, symbol);
3852         }
3853
3854         /* delay test for incomplete type, because we might have (void)
3855          * which is legal but incomplete... */
3856
3857         return type;
3858 }
3859
3860 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
3861                                   declarator_flags_t flags)
3862 {
3863         parse_declarator_env_t env;
3864         memset(&env, 0, sizeof(env));
3865         env.may_be_abstract = (flags & DECL_MAY_BE_ABSTRACT) != 0;
3866
3867         construct_type_t *construct_type = parse_inner_declarator(&env);
3868         type_t           *orig_type      =
3869                 construct_declarator_type(construct_type, specifiers->type);
3870         type_t           *type           = skip_typeref(orig_type);
3871
3872         if (construct_type != NULL) {
3873                 obstack_free(&temp_obst, construct_type);
3874         }
3875
3876         attribute_t *attributes = parse_attributes(env.attributes);
3877         /* append (shared) specifier attribute behind attributes of this
3878          * declarator */
3879         attribute_t **anchor = &attributes;
3880         while (*anchor != NULL)
3881                 anchor = &(*anchor)->next;
3882         *anchor = specifiers->attributes;
3883
3884         entity_t *entity;
3885         if (specifiers->storage_class == STORAGE_CLASS_TYPEDEF) {
3886                 entity                       = allocate_entity_zero(ENTITY_TYPEDEF);
3887                 entity->base.namespc         = NAMESPACE_NORMAL;
3888                 entity->base.symbol          = env.symbol;
3889                 entity->base.source_position = env.source_position;
3890                 entity->typedefe.type        = orig_type;
3891
3892                 if (anonymous_entity != NULL) {
3893                         if (is_type_compound(type)) {
3894                                 assert(anonymous_entity->compound.alias == NULL);
3895                                 assert(anonymous_entity->kind == ENTITY_STRUCT ||
3896                                        anonymous_entity->kind == ENTITY_UNION);
3897                                 anonymous_entity->compound.alias = entity;
3898                                 anonymous_entity = NULL;
3899                         } else if (is_type_enum(type)) {
3900                                 assert(anonymous_entity->enume.alias == NULL);
3901                                 assert(anonymous_entity->kind == ENTITY_ENUM);
3902                                 anonymous_entity->enume.alias = entity;
3903                                 anonymous_entity = NULL;
3904                         }
3905                 }
3906         } else {
3907                 /* create a declaration type entity */
3908                 if (flags & DECL_CREATE_COMPOUND_MEMBER) {
3909                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
3910
3911                         if (env.symbol != NULL) {
3912                                 if (specifiers->is_inline && is_type_valid(type)) {
3913                                         errorf(&env.source_position,
3914                                                         "compound member '%Y' declared 'inline'", env.symbol);
3915                                 }
3916
3917                                 if (specifiers->thread_local ||
3918                                                 specifiers->storage_class != STORAGE_CLASS_NONE) {
3919                                         errorf(&env.source_position,
3920                                                         "compound member '%Y' must have no storage class",
3921                                                         env.symbol);
3922                                 }
3923                         }
3924                 } else if (flags & DECL_IS_PARAMETER) {
3925                         orig_type = semantic_parameter(&env.source_position, orig_type,
3926                                                        specifiers, env.symbol);
3927
3928                         entity = allocate_entity_zero(ENTITY_PARAMETER);
3929                 } else if (is_type_function(type)) {
3930                         entity = allocate_entity_zero(ENTITY_FUNCTION);
3931
3932                         entity->function.is_inline  = specifiers->is_inline;
3933                         entity->function.parameters = env.parameters;
3934
3935                         if (env.symbol != NULL) {
3936                                 /* this needs fixes for C++ */
3937                                 bool in_function_scope = current_function != NULL;
3938
3939                                 if (specifiers->thread_local || (
3940                                                         specifiers->storage_class != STORAGE_CLASS_EXTERN &&
3941                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
3942                                                         (in_function_scope || specifiers->storage_class != STORAGE_CLASS_STATIC)
3943                                                 )) {
3944                                         errorf(&env.source_position,
3945                                                         "invalid storage class for function '%Y'", env.symbol);
3946                                 }
3947                         }
3948                 } else {
3949                         entity = allocate_entity_zero(ENTITY_VARIABLE);
3950
3951                         entity->variable.thread_local = specifiers->thread_local;
3952
3953                         if (env.symbol != NULL) {
3954                                 if (specifiers->is_inline && is_type_valid(type)) {
3955                                         errorf(&env.source_position,
3956                                                         "variable '%Y' declared 'inline'", env.symbol);
3957                                 }
3958
3959                                 bool invalid_storage_class = false;
3960                                 if (current_scope == file_scope) {
3961                                         if (specifiers->storage_class != STORAGE_CLASS_EXTERN &&
3962                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
3963                                                         specifiers->storage_class != STORAGE_CLASS_STATIC) {
3964                                                 invalid_storage_class = true;
3965                                         }
3966                                 } else {
3967                                         if (specifiers->thread_local &&
3968                                                         specifiers->storage_class == STORAGE_CLASS_NONE) {
3969                                                 invalid_storage_class = true;
3970                                         }
3971                                 }
3972                                 if (invalid_storage_class) {
3973                                         errorf(&env.source_position,
3974                                                         "invalid storage class for variable '%Y'", env.symbol);
3975                                 }
3976                         }
3977                 }
3978
3979                 if (env.symbol != NULL) {
3980                         entity->base.symbol          = env.symbol;
3981                         entity->base.source_position = env.source_position;
3982                 } else {
3983                         entity->base.source_position = specifiers->source_position;
3984                 }
3985                 entity->base.namespc           = NAMESPACE_NORMAL;
3986                 entity->declaration.type       = orig_type;
3987                 entity->declaration.alignment  = get_type_alignment(orig_type);
3988                 entity->declaration.modifiers  = env.modifiers;
3989                 entity->declaration.attributes = attributes;
3990
3991                 storage_class_t storage_class = specifiers->storage_class;
3992                 entity->declaration.declared_storage_class = storage_class;
3993
3994                 if (storage_class == STORAGE_CLASS_NONE && current_function != NULL)
3995                         storage_class = STORAGE_CLASS_AUTO;
3996                 entity->declaration.storage_class = storage_class;
3997         }
3998
3999         if (attributes != NULL) {
4000                 handle_entity_attributes(attributes, entity);
4001         }
4002
4003         return entity;
4004 }
4005
4006 static type_t *parse_abstract_declarator(type_t *base_type)
4007 {
4008         parse_declarator_env_t env;
4009         memset(&env, 0, sizeof(env));
4010         env.may_be_abstract = true;
4011         env.must_be_abstract = true;
4012
4013         construct_type_t *construct_type = parse_inner_declarator(&env);
4014
4015         type_t *result = construct_declarator_type(construct_type, base_type);
4016         if (construct_type != NULL) {
4017                 obstack_free(&temp_obst, construct_type);
4018         }
4019         result = handle_type_attributes(env.attributes, result);
4020
4021         return result;
4022 }
4023
4024 /**
4025  * Check if the declaration of main is suspicious.  main should be a
4026  * function with external linkage, returning int, taking either zero
4027  * arguments, two, or three arguments of appropriate types, ie.
4028  *
4029  * int main([ int argc, char **argv [, char **env ] ]).
4030  *
4031  * @param decl    the declaration to check
4032  * @param type    the function type of the declaration
4033  */
4034 static void check_main(const entity_t *entity)
4035 {
4036         const source_position_t *pos = &entity->base.source_position;
4037         if (entity->kind != ENTITY_FUNCTION) {
4038                 warningf(pos, "'main' is not a function");
4039                 return;
4040         }
4041
4042         if (entity->declaration.storage_class == STORAGE_CLASS_STATIC) {
4043                 warningf(pos, "'main' is normally a non-static function");
4044         }
4045
4046         type_t *type = skip_typeref(entity->declaration.type);
4047         assert(is_type_function(type));
4048
4049         function_type_t *func_type = &type->function;
4050         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4051                 warningf(pos, "return type of 'main' should be 'int', but is '%T'",
4052                          func_type->return_type);
4053         }
4054         const function_parameter_t *parm = func_type->parameters;
4055         if (parm != NULL) {
4056                 type_t *const first_type        = skip_typeref(parm->type);
4057                 type_t *const first_type_unqual = get_unqualified_type(first_type);
4058                 if (!types_compatible(first_type_unqual, type_int)) {
4059                         warningf(pos,
4060                                  "first argument of 'main' should be 'int', but is '%T'",
4061                                  parm->type);
4062                 }
4063                 parm = parm->next;
4064                 if (parm != NULL) {
4065                         type_t *const second_type = skip_typeref(parm->type);
4066                         type_t *const second_type_unqual
4067                                 = get_unqualified_type(second_type);
4068                         if (!types_compatible(second_type_unqual, type_char_ptr_ptr)) {
4069                                 warningf(pos, "second argument of 'main' should be 'char**', but is '%T'",
4070                                          parm->type);
4071                         }
4072                         parm = parm->next;
4073                         if (parm != NULL) {
4074                                 type_t *const third_type = skip_typeref(parm->type);
4075                                 type_t *const third_type_unqual
4076                                         = get_unqualified_type(third_type);
4077                                 if (!types_compatible(third_type_unqual, type_char_ptr_ptr)) {
4078                                         warningf(pos, "third argument of 'main' should be 'char**', but is '%T'",
4079                                                  parm->type);
4080                                 }
4081                                 parm = parm->next;
4082                                 if (parm != NULL)
4083                                         goto warn_arg_count;
4084                         }
4085                 } else {
4086 warn_arg_count:
4087                         warningf(pos, "'main' takes only zero, two or three arguments");
4088                 }
4089         }
4090 }
4091
4092 /**
4093  * Check if a symbol is the equal to "main".
4094  */
4095 static bool is_sym_main(const symbol_t *const sym)
4096 {
4097         return strcmp(sym->string, "main") == 0;
4098 }
4099
4100 static void error_redefined_as_different_kind(const source_position_t *pos,
4101                 const entity_t *old, entity_kind_t new_kind)
4102 {
4103         errorf(pos, "redeclaration of %s '%Y' as %s (declared %P)",
4104                get_entity_kind_name(old->kind), old->base.symbol,
4105                get_entity_kind_name(new_kind), &old->base.source_position);
4106 }
4107
4108 static bool is_entity_valid(entity_t *const ent)
4109 {
4110         if (is_declaration(ent)) {
4111                 return is_type_valid(skip_typeref(ent->declaration.type));
4112         } else if (ent->kind == ENTITY_TYPEDEF) {
4113                 return is_type_valid(skip_typeref(ent->typedefe.type));
4114         }
4115         return true;
4116 }
4117
4118 static bool contains_attribute(const attribute_t *list, const attribute_t *attr)
4119 {
4120         for (const attribute_t *tattr = list; tattr != NULL; tattr = tattr->next) {
4121                 if (attributes_equal(tattr, attr))
4122                         return true;
4123         }
4124         return false;
4125 }
4126
4127 /**
4128  * test wether new_list contains any attributes not included in old_list
4129  */
4130 static bool has_new_attributes(const attribute_t *old_list,
4131                                const attribute_t *new_list)
4132 {
4133         for (const attribute_t *attr = new_list; attr != NULL; attr = attr->next) {
4134                 if (!contains_attribute(old_list, attr))
4135                         return true;
4136         }
4137         return false;
4138 }
4139
4140 /**
4141  * Merge in attributes from an attribute list (probably from a previous
4142  * declaration with the same name). Warning: destroys the old structure
4143  * of the attribute list - don't reuse attributes after this call.
4144  */
4145 static void merge_in_attributes(declaration_t *decl, attribute_t *attributes)
4146 {
4147         attribute_t *next;
4148         for (attribute_t *attr = attributes; attr != NULL; attr = next) {
4149                 next = attr->next;
4150                 if (contains_attribute(decl->attributes, attr))
4151                         continue;
4152
4153                 /* move attribute to new declarations attributes list */
4154                 attr->next       = decl->attributes;
4155                 decl->attributes = attr;
4156         }
4157 }
4158
4159 /**
4160  * record entities for the NAMESPACE_NORMAL, and produce error messages/warnings
4161  * for various problems that occur for multiple definitions
4162  */
4163 entity_t *record_entity(entity_t *entity, const bool is_definition)
4164 {
4165         const symbol_t *const    symbol  = entity->base.symbol;
4166         const namespace_tag_t    namespc = (namespace_tag_t)entity->base.namespc;
4167         const source_position_t *pos     = &entity->base.source_position;
4168
4169         /* can happen in error cases */
4170         if (symbol == NULL)
4171                 return entity;
4172
4173         entity_t *const previous_entity = get_entity(symbol, namespc);
4174         /* pushing the same entity twice will break the stack structure */
4175         assert(previous_entity != entity);
4176
4177         if (entity->kind == ENTITY_FUNCTION) {
4178                 type_t *const orig_type = entity->declaration.type;
4179                 type_t *const type      = skip_typeref(orig_type);
4180
4181                 assert(is_type_function(type));
4182                 if (type->function.unspecified_parameters &&
4183                                 warning.strict_prototypes &&
4184                                 previous_entity == NULL) {
4185                         warningf(pos, "function declaration '%#T' is not a prototype",
4186                                          orig_type, symbol);
4187                 }
4188
4189                 if (warning.main && current_scope == file_scope
4190                                 && is_sym_main(symbol)) {
4191                         check_main(entity);
4192                 }
4193         }
4194
4195         if (is_declaration(entity) &&
4196                         warning.nested_externs &&
4197                         entity->declaration.storage_class == STORAGE_CLASS_EXTERN &&
4198                         current_scope != file_scope) {
4199                 warningf(pos, "nested extern declaration of '%#T'",
4200                          entity->declaration.type, symbol);
4201         }
4202
4203         if (previous_entity != NULL) {
4204                 if (previous_entity->base.parent_scope == &current_function->parameters &&
4205                                 previous_entity->base.parent_scope->depth + 1 == current_scope->depth) {
4206                         assert(previous_entity->kind == ENTITY_PARAMETER);
4207                         errorf(pos,
4208                                         "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
4209                                         entity->declaration.type, symbol,
4210                                         previous_entity->declaration.type, symbol,
4211                                         &previous_entity->base.source_position);
4212                         goto finish;
4213                 }
4214
4215                 if (previous_entity->base.parent_scope == current_scope) {
4216                         if (previous_entity->kind != entity->kind) {
4217                                 if (is_entity_valid(previous_entity) && is_entity_valid(entity)) {
4218                                         error_redefined_as_different_kind(pos, previous_entity,
4219                                                         entity->kind);
4220                                 }
4221                                 goto finish;
4222                         }
4223                         if (previous_entity->kind == ENTITY_ENUM_VALUE) {
4224                                 errorf(pos, "redeclaration of enum entry '%Y' (declared %P)",
4225                                                 symbol, &previous_entity->base.source_position);
4226                                 goto finish;
4227                         }
4228                         if (previous_entity->kind == ENTITY_TYPEDEF) {
4229                                 /* TODO: C++ allows this for exactly the same type */
4230                                 errorf(pos, "redefinition of typedef '%Y' (declared %P)",
4231                                                 symbol, &previous_entity->base.source_position);
4232                                 goto finish;
4233                         }
4234
4235                         /* at this point we should have only VARIABLES or FUNCTIONS */
4236                         assert(is_declaration(previous_entity) && is_declaration(entity));
4237
4238                         declaration_t *const prev_decl = &previous_entity->declaration;
4239                         declaration_t *const decl      = &entity->declaration;
4240
4241                         /* can happen for K&R style declarations */
4242                         if (prev_decl->type       == NULL             &&
4243                                         previous_entity->kind == ENTITY_PARAMETER &&
4244                                         entity->kind          == ENTITY_PARAMETER) {
4245                                 prev_decl->type                   = decl->type;
4246                                 prev_decl->storage_class          = decl->storage_class;
4247                                 prev_decl->declared_storage_class = decl->declared_storage_class;
4248                                 prev_decl->modifiers              = decl->modifiers;
4249                                 return previous_entity;
4250                         }
4251
4252                         type_t *const orig_type = decl->type;
4253                         assert(orig_type != NULL);
4254                         type_t *const type      = skip_typeref(orig_type);
4255                         type_t *const prev_type = skip_typeref(prev_decl->type);
4256
4257                         if (!types_compatible(type, prev_type)) {
4258                                 errorf(pos,
4259                                                 "declaration '%#T' is incompatible with '%#T' (declared %P)",
4260                                                 orig_type, symbol, prev_decl->type, symbol,
4261                                                 &previous_entity->base.source_position);
4262                         } else {
4263                                 unsigned old_storage_class = prev_decl->storage_class;
4264
4265                                 if (warning.redundant_decls               &&
4266                                                 is_definition                     &&
4267                                                 !prev_decl->used                  &&
4268                                                 !(prev_decl->modifiers & DM_USED) &&
4269                                                 prev_decl->storage_class == STORAGE_CLASS_STATIC) {
4270                                         warningf(&previous_entity->base.source_position,
4271                                                         "unnecessary static forward declaration for '%#T'",
4272                                                         prev_decl->type, symbol);
4273                                 }
4274
4275                                 storage_class_t new_storage_class = decl->storage_class;
4276
4277                                 /* pretend no storage class means extern for function
4278                                  * declarations (except if the previous declaration is neither
4279                                  * none nor extern) */
4280                                 if (entity->kind == ENTITY_FUNCTION) {
4281                                         /* the previous declaration could have unspecified parameters or
4282                                          * be a typedef, so use the new type */
4283                                         if (prev_type->function.unspecified_parameters || is_definition)
4284                                                 prev_decl->type = type;
4285
4286                                         switch (old_storage_class) {
4287                                                 case STORAGE_CLASS_NONE:
4288                                                         old_storage_class = STORAGE_CLASS_EXTERN;
4289                                                         /* FALLTHROUGH */
4290
4291                                                 case STORAGE_CLASS_EXTERN:
4292                                                         if (is_definition) {
4293                                                                 if (warning.missing_prototypes &&
4294                                                                                 prev_type->function.unspecified_parameters &&
4295                                                                                 !is_sym_main(symbol)) {
4296                                                                         warningf(pos, "no previous prototype for '%#T'",
4297                                                                                         orig_type, symbol);
4298                                                                 }
4299                                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4300                                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4301                                                         }
4302                                                         break;
4303
4304                                                 default:
4305                                                         break;
4306                                         }
4307                                 } else if (is_type_incomplete(prev_type)) {
4308                                         prev_decl->type = type;
4309                                 }
4310
4311                                 if (old_storage_class == STORAGE_CLASS_EXTERN &&
4312                                                 new_storage_class == STORAGE_CLASS_EXTERN) {
4313
4314 warn_redundant_declaration: ;
4315                                         bool has_new_attrs
4316                                                 = has_new_attributes(prev_decl->attributes,
4317                                                                      decl->attributes);
4318                                         if (has_new_attrs) {
4319                                                 merge_in_attributes(decl, prev_decl->attributes);
4320                                         } else if (!is_definition        &&
4321                                                         warning.redundant_decls  &&
4322                                                         is_type_valid(prev_type) &&
4323                                                         strcmp(previous_entity->base.source_position.input_name,
4324                                                                 "<builtin>") != 0) {
4325                                                 warningf(pos,
4326                                                          "redundant declaration for '%Y' (declared %P)",
4327                                                          symbol, &previous_entity->base.source_position);
4328                                         }
4329                                 } else if (current_function == NULL) {
4330                                         if (old_storage_class != STORAGE_CLASS_STATIC &&
4331                                                         new_storage_class == STORAGE_CLASS_STATIC) {
4332                                                 errorf(pos,
4333                                                        "static declaration of '%Y' follows non-static declaration (declared %P)",
4334                                                        symbol, &previous_entity->base.source_position);
4335                                         } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4336                                                 prev_decl->storage_class          = STORAGE_CLASS_NONE;
4337                                                 prev_decl->declared_storage_class = STORAGE_CLASS_NONE;
4338                                         } else {
4339                                                 /* ISO/IEC 14882:1998(E) §C.1.2:1 */
4340                                                 if (c_mode & _CXX)
4341                                                         goto error_redeclaration;
4342                                                 goto warn_redundant_declaration;
4343                                         }
4344                                 } else if (is_type_valid(prev_type)) {
4345                                         if (old_storage_class == new_storage_class) {
4346 error_redeclaration:
4347                                                 errorf(pos, "redeclaration of '%Y' (declared %P)",
4348                                                                 symbol, &previous_entity->base.source_position);
4349                                         } else {
4350                                                 errorf(pos,
4351                                                                 "redeclaration of '%Y' with different linkage (declared %P)",
4352                                                                 symbol, &previous_entity->base.source_position);
4353                                         }
4354                                 }
4355                         }
4356
4357                         prev_decl->modifiers |= decl->modifiers;
4358                         if (entity->kind == ENTITY_FUNCTION) {
4359                                 previous_entity->function.is_inline |= entity->function.is_inline;
4360                         }
4361                         return previous_entity;
4362                 }
4363
4364                 if (warning.shadow) {
4365                         warningf(pos, "%s '%Y' shadows %s (declared %P)",
4366                                         get_entity_kind_name(entity->kind), symbol,
4367                                         get_entity_kind_name(previous_entity->kind),
4368                                         &previous_entity->base.source_position);
4369                 }
4370         }
4371
4372         if (entity->kind == ENTITY_FUNCTION) {
4373                 if (is_definition &&
4374                                 entity->declaration.storage_class != STORAGE_CLASS_STATIC) {
4375                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4376                                 warningf(pos, "no previous prototype for '%#T'",
4377                                          entity->declaration.type, symbol);
4378                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4379                                 warningf(pos, "no previous declaration for '%#T'",
4380                                          entity->declaration.type, symbol);
4381                         }
4382                 }
4383         } else if (warning.missing_declarations &&
4384                         entity->kind == ENTITY_VARIABLE &&
4385                         current_scope == file_scope) {
4386                 declaration_t *declaration = &entity->declaration;
4387                 if (declaration->storage_class == STORAGE_CLASS_NONE) {
4388                         warningf(pos, "no previous declaration for '%#T'",
4389                                  declaration->type, symbol);
4390                 }
4391         }
4392
4393 finish:
4394         assert(entity->base.parent_scope == NULL);
4395         assert(current_scope != NULL);
4396
4397         entity->base.parent_scope = current_scope;
4398         entity->base.namespc      = NAMESPACE_NORMAL;
4399         environment_push(entity);
4400         append_entity(current_scope, entity);
4401
4402         return entity;
4403 }
4404
4405 static void parser_error_multiple_definition(entity_t *entity,
4406                 const source_position_t *source_position)
4407 {
4408         errorf(source_position, "multiple definition of '%Y' (declared %P)",
4409                entity->base.symbol, &entity->base.source_position);
4410 }
4411
4412 static bool is_declaration_specifier(const token_t *token,
4413                                      bool only_specifiers_qualifiers)
4414 {
4415         switch (token->type) {
4416                 TYPE_SPECIFIERS
4417                 TYPE_QUALIFIERS
4418                         return true;
4419                 case T_IDENTIFIER:
4420                         return is_typedef_symbol(token->symbol);
4421
4422                 case T___extension__:
4423                 STORAGE_CLASSES
4424                         return !only_specifiers_qualifiers;
4425
4426                 default:
4427                         return false;
4428         }
4429 }
4430
4431 static void parse_init_declarator_rest(entity_t *entity)
4432 {
4433         type_t *orig_type = type_error_type;
4434
4435         if (entity->base.kind == ENTITY_TYPEDEF) {
4436                 errorf(&entity->base.source_position,
4437                        "typedef '%Y' is initialized (use __typeof__ instead)",
4438                        entity->base.symbol);
4439         } else {
4440                 assert(is_declaration(entity));
4441                 orig_type = entity->declaration.type;
4442         }
4443         eat('=');
4444
4445         type_t *type = skip_typeref(orig_type);
4446
4447         if (entity->kind == ENTITY_VARIABLE
4448                         && entity->variable.initializer != NULL) {
4449                 parser_error_multiple_definition(entity, HERE);
4450         }
4451
4452         declaration_t *const declaration = &entity->declaration;
4453         bool must_be_constant = false;
4454         if (declaration->storage_class == STORAGE_CLASS_STATIC ||
4455             entity->base.parent_scope  == file_scope) {
4456                 must_be_constant = true;
4457         }
4458
4459         if (is_type_function(type)) {
4460                 errorf(&entity->base.source_position,
4461                        "function '%#T' is initialized like a variable",
4462                        orig_type, entity->base.symbol);
4463                 orig_type = type_error_type;
4464         }
4465
4466         parse_initializer_env_t env;
4467         env.type             = orig_type;
4468         env.must_be_constant = must_be_constant;
4469         env.entity           = entity;
4470         current_init_decl    = entity;
4471
4472         initializer_t *initializer = parse_initializer(&env);
4473         current_init_decl = NULL;
4474
4475         if (entity->kind == ENTITY_VARIABLE) {
4476                 /* §6.7.5:22  array initializers for arrays with unknown size
4477                  * determine the array type size */
4478                 declaration->type            = env.type;
4479                 entity->variable.initializer = initializer;
4480         }
4481 }
4482
4483 /* parse rest of a declaration without any declarator */
4484 static void parse_anonymous_declaration_rest(
4485                 const declaration_specifiers_t *specifiers)
4486 {
4487         eat(';');
4488         anonymous_entity = NULL;
4489
4490         if (warning.other) {
4491                 if (specifiers->storage_class != STORAGE_CLASS_NONE ||
4492                                 specifiers->thread_local) {
4493                         warningf(&specifiers->source_position,
4494                                  "useless storage class in empty declaration");
4495                 }
4496
4497                 type_t *type = specifiers->type;
4498                 switch (type->kind) {
4499                         case TYPE_COMPOUND_STRUCT:
4500                         case TYPE_COMPOUND_UNION: {
4501                                 if (type->compound.compound->base.symbol == NULL) {
4502                                         warningf(&specifiers->source_position,
4503                                                  "unnamed struct/union that defines no instances");
4504                                 }
4505                                 break;
4506                         }
4507
4508                         case TYPE_ENUM:
4509                                 break;
4510
4511                         default:
4512                                 warningf(&specifiers->source_position, "empty declaration");
4513                                 break;
4514                 }
4515         }
4516 }
4517
4518 static void check_variable_type_complete(entity_t *ent)
4519 {
4520         if (ent->kind != ENTITY_VARIABLE)
4521                 return;
4522
4523         /* §6.7:7  If an identifier for an object is declared with no linkage, the
4524          *         type for the object shall be complete [...] */
4525         declaration_t *decl = &ent->declaration;
4526         if (decl->storage_class == STORAGE_CLASS_EXTERN ||
4527                         decl->storage_class == STORAGE_CLASS_STATIC)
4528                 return;
4529
4530         type_t *const orig_type = decl->type;
4531         type_t *const type      = skip_typeref(orig_type);
4532         if (!is_type_incomplete(type))
4533                 return;
4534
4535         /* §6.9.2:2 and §6.9.2:5: At the end of the translation incomplete arrays
4536          * are given length one. */
4537         if (is_type_array(type) && ent->base.parent_scope == file_scope) {
4538                 ARR_APP1(declaration_t*, incomplete_arrays, decl);
4539                 return;
4540         }
4541
4542         errorf(&ent->base.source_position, "variable '%#T' has incomplete type",
4543                         orig_type, ent->base.symbol);
4544 }
4545
4546
4547 static void parse_declaration_rest(entity_t *ndeclaration,
4548                 const declaration_specifiers_t *specifiers,
4549                 parsed_declaration_func         finished_declaration,
4550                 declarator_flags_t              flags)
4551 {
4552         add_anchor_token(';');
4553         add_anchor_token(',');
4554         while (true) {
4555                 entity_t *entity = finished_declaration(ndeclaration, token.type == '=');
4556
4557                 if (token.type == '=') {
4558                         parse_init_declarator_rest(entity);
4559                 } else if (entity->kind == ENTITY_VARIABLE) {
4560                         /* ISO/IEC 14882:1998(E) §8.5.3:3  The initializer can be omitted
4561                          * [...] where the extern specifier is explicitly used. */
4562                         declaration_t *decl = &entity->declaration;
4563                         if (decl->storage_class != STORAGE_CLASS_EXTERN) {
4564                                 type_t *type = decl->type;
4565                                 if (is_type_reference(skip_typeref(type))) {
4566                                         errorf(&entity->base.source_position,
4567                                                         "reference '%#T' must be initialized",
4568                                                         type, entity->base.symbol);
4569                                 }
4570                         }
4571                 }
4572
4573                 check_variable_type_complete(entity);
4574
4575                 if (!next_if(','))
4576                         break;
4577
4578                 add_anchor_token('=');
4579                 ndeclaration = parse_declarator(specifiers, flags);
4580                 rem_anchor_token('=');
4581         }
4582         expect(';', end_error);
4583
4584 end_error:
4585         anonymous_entity = NULL;
4586         rem_anchor_token(';');
4587         rem_anchor_token(',');
4588 }
4589
4590 static entity_t *finished_kr_declaration(entity_t *entity, bool is_definition)
4591 {
4592         symbol_t *symbol = entity->base.symbol;
4593         if (symbol == NULL) {
4594                 errorf(HERE, "anonymous declaration not valid as function parameter");
4595                 return entity;
4596         }
4597
4598         assert(entity->base.namespc == NAMESPACE_NORMAL);
4599         entity_t *previous_entity = get_entity(symbol, NAMESPACE_NORMAL);
4600         if (previous_entity == NULL
4601                         || previous_entity->base.parent_scope != current_scope) {
4602                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4603                        symbol);
4604                 return entity;
4605         }
4606
4607         if (is_definition) {
4608                 errorf(HERE, "parameter '%Y' is initialised", entity->base.symbol);
4609         }
4610
4611         return record_entity(entity, false);
4612 }
4613
4614 static void parse_declaration(parsed_declaration_func finished_declaration,
4615                               declarator_flags_t      flags)
4616 {
4617         declaration_specifiers_t specifiers;
4618         memset(&specifiers, 0, sizeof(specifiers));
4619
4620         add_anchor_token(';');
4621         parse_declaration_specifiers(&specifiers);
4622         rem_anchor_token(';');
4623
4624         if (token.type == ';') {
4625                 parse_anonymous_declaration_rest(&specifiers);
4626         } else {
4627                 entity_t *entity = parse_declarator(&specifiers, flags);
4628                 parse_declaration_rest(entity, &specifiers, finished_declaration, flags);
4629         }
4630 }
4631
4632 /* §6.5.2.2:6 */
4633 static type_t *get_default_promoted_type(type_t *orig_type)
4634 {
4635         type_t *result = orig_type;
4636
4637         type_t *type = skip_typeref(orig_type);
4638         if (is_type_integer(type)) {
4639                 result = promote_integer(type);
4640         } else if (is_type_atomic(type, ATOMIC_TYPE_FLOAT)) {
4641                 result = type_double;
4642         }
4643
4644         return result;
4645 }
4646
4647 static void parse_kr_declaration_list(entity_t *entity)
4648 {
4649         if (entity->kind != ENTITY_FUNCTION)
4650                 return;
4651
4652         type_t *type = skip_typeref(entity->declaration.type);
4653         assert(is_type_function(type));
4654         if (!type->function.kr_style_parameters)
4655                 return;
4656
4657         add_anchor_token('{');
4658
4659         /* push function parameters */
4660         size_t const  top       = environment_top();
4661         scope_t      *old_scope = scope_push(&entity->function.parameters);
4662
4663         entity_t *parameter = entity->function.parameters.entities;
4664         for ( ; parameter != NULL; parameter = parameter->base.next) {
4665                 assert(parameter->base.parent_scope == NULL);
4666                 parameter->base.parent_scope = current_scope;
4667                 environment_push(parameter);
4668         }
4669
4670         /* parse declaration list */
4671         for (;;) {
4672                 switch (token.type) {
4673                         DECLARATION_START
4674                         case T___extension__:
4675                         /* This covers symbols, which are no type, too, and results in
4676                          * better error messages.  The typical cases are misspelled type
4677                          * names and missing includes. */
4678                         case T_IDENTIFIER:
4679                                 parse_declaration(finished_kr_declaration, DECL_IS_PARAMETER);
4680                                 break;
4681                         default:
4682                                 goto decl_list_end;
4683                 }
4684         }
4685 decl_list_end:
4686
4687         /* pop function parameters */
4688         assert(current_scope == &entity->function.parameters);
4689         scope_pop(old_scope);
4690         environment_pop_to(top);
4691
4692         /* update function type */
4693         type_t *new_type = duplicate_type(type);
4694
4695         function_parameter_t  *parameters = NULL;
4696         function_parameter_t **anchor     = &parameters;
4697
4698         /* did we have an earlier prototype? */
4699         entity_t *proto_type = get_entity(entity->base.symbol, NAMESPACE_NORMAL);
4700         if (proto_type != NULL && proto_type->kind != ENTITY_FUNCTION)
4701                 proto_type = NULL;
4702
4703         function_parameter_t *proto_parameter = NULL;
4704         if (proto_type != NULL) {
4705                 type_t *proto_type_type = proto_type->declaration.type;
4706                 proto_parameter         = proto_type_type->function.parameters;
4707                 /* If a K&R function definition has a variadic prototype earlier, then
4708                  * make the function definition variadic, too. This should conform to
4709                  * §6.7.5.3:15 and §6.9.1:8. */
4710                 new_type->function.variadic = proto_type_type->function.variadic;
4711         } else {
4712                 /* §6.9.1.7: A K&R style parameter list does NOT act as a function
4713                  * prototype */
4714                 new_type->function.unspecified_parameters = true;
4715         }
4716
4717         bool need_incompatible_warning = false;
4718         parameter = entity->function.parameters.entities;
4719         for (; parameter != NULL; parameter = parameter->base.next,
4720                         proto_parameter =
4721                                 proto_parameter == NULL ? NULL : proto_parameter->next) {
4722                 if (parameter->kind != ENTITY_PARAMETER)
4723                         continue;
4724
4725                 type_t *parameter_type = parameter->declaration.type;
4726                 if (parameter_type == NULL) {
4727                         if (strict_mode) {
4728                                 errorf(HERE, "no type specified for function parameter '%Y'",
4729                                        parameter->base.symbol);
4730                                 parameter_type = type_error_type;
4731                         } else {
4732                                 if (warning.implicit_int) {
4733                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
4734                                                  parameter->base.symbol);
4735                                 }
4736                                 parameter_type = type_int;
4737                         }
4738                         parameter->declaration.type = parameter_type;
4739                 }
4740
4741                 semantic_parameter_incomplete(parameter);
4742
4743                 /* we need the default promoted types for the function type */
4744                 type_t *not_promoted = parameter_type;
4745                 parameter_type       = get_default_promoted_type(parameter_type);
4746
4747                 /* gcc special: if the type of the prototype matches the unpromoted
4748                  * type don't promote */
4749                 if (!strict_mode && proto_parameter != NULL) {
4750                         type_t *proto_p_type = skip_typeref(proto_parameter->type);
4751                         type_t *promo_skip   = skip_typeref(parameter_type);
4752                         type_t *param_skip   = skip_typeref(not_promoted);
4753                         if (!types_compatible(proto_p_type, promo_skip)
4754                                 && types_compatible(proto_p_type, param_skip)) {
4755                                 /* don't promote */
4756                                 need_incompatible_warning = true;
4757                                 parameter_type = not_promoted;
4758                         }
4759                 }
4760                 function_parameter_t *const parameter
4761                         = allocate_parameter(parameter_type);
4762
4763                 *anchor = parameter;
4764                 anchor  = &parameter->next;
4765         }
4766
4767         new_type->function.parameters = parameters;
4768         new_type = identify_new_type(new_type);
4769
4770         if (warning.other && need_incompatible_warning) {
4771                 type_t *proto_type_type = proto_type->declaration.type;
4772                 warningf(HERE,
4773                          "declaration '%#T' is incompatible with '%#T' (declared %P)",
4774                          proto_type_type, proto_type->base.symbol,
4775                          new_type, entity->base.symbol,
4776                          &proto_type->base.source_position);
4777         }
4778
4779         entity->declaration.type = new_type;
4780
4781         rem_anchor_token('{');
4782 }
4783
4784 static bool first_err = true;
4785
4786 /**
4787  * When called with first_err set, prints the name of the current function,
4788  * else does noting.
4789  */
4790 static void print_in_function(void)
4791 {
4792         if (first_err) {
4793                 first_err = false;
4794                 diagnosticf("%s: In function '%Y':\n",
4795                             current_function->base.base.source_position.input_name,
4796                             current_function->base.base.symbol);
4797         }
4798 }
4799
4800 /**
4801  * Check if all labels are defined in the current function.
4802  * Check if all labels are used in the current function.
4803  */
4804 static void check_labels(void)
4805 {
4806         for (const goto_statement_t *goto_statement = goto_first;
4807             goto_statement != NULL;
4808             goto_statement = goto_statement->next) {
4809                 /* skip computed gotos */
4810                 if (goto_statement->expression != NULL)
4811                         continue;
4812
4813                 label_t *label = goto_statement->label;
4814
4815                 label->used = true;
4816                 if (label->base.source_position.input_name == NULL) {
4817                         print_in_function();
4818                         errorf(&goto_statement->base.source_position,
4819                                "label '%Y' used but not defined", label->base.symbol);
4820                  }
4821         }
4822
4823         if (warning.unused_label) {
4824                 for (const label_statement_t *label_statement = label_first;
4825                          label_statement != NULL;
4826                          label_statement = label_statement->next) {
4827                         label_t *label = label_statement->label;
4828
4829                         if (! label->used) {
4830                                 print_in_function();
4831                                 warningf(&label_statement->base.source_position,
4832                                          "label '%Y' defined but not used", label->base.symbol);
4833                         }
4834                 }
4835         }
4836 }
4837
4838 static void warn_unused_entity(entity_t *entity, entity_t *last)
4839 {
4840         entity_t const *const end = last != NULL ? last->base.next : NULL;
4841         for (; entity != end; entity = entity->base.next) {
4842                 if (!is_declaration(entity))
4843                         continue;
4844
4845                 declaration_t *declaration = &entity->declaration;
4846                 if (declaration->implicit)
4847                         continue;
4848
4849                 if (!declaration->used) {
4850                         print_in_function();
4851                         const char *what = get_entity_kind_name(entity->kind);
4852                         warningf(&entity->base.source_position, "%s '%Y' is unused",
4853                                  what, entity->base.symbol);
4854                 } else if (entity->kind == ENTITY_VARIABLE && !entity->variable.read) {
4855                         print_in_function();
4856                         const char *what = get_entity_kind_name(entity->kind);
4857                         warningf(&entity->base.source_position, "%s '%Y' is never read",
4858                                  what, entity->base.symbol);
4859                 }
4860         }
4861 }
4862
4863 static void check_unused_variables(statement_t *const stmt, void *const env)
4864 {
4865         (void)env;
4866
4867         switch (stmt->kind) {
4868                 case STATEMENT_DECLARATION: {
4869                         declaration_statement_t const *const decls = &stmt->declaration;
4870                         warn_unused_entity(decls->declarations_begin,
4871                                            decls->declarations_end);
4872                         return;
4873                 }
4874
4875                 case STATEMENT_FOR:
4876                         warn_unused_entity(stmt->fors.scope.entities, NULL);
4877                         return;
4878
4879                 default:
4880                         return;
4881         }
4882 }
4883
4884 /**
4885  * Check declarations of current_function for unused entities.
4886  */
4887 static void check_declarations(void)
4888 {
4889         if (warning.unused_parameter) {
4890                 const scope_t *scope = &current_function->parameters;
4891
4892                 /* do not issue unused warnings for main */
4893                 if (!is_sym_main(current_function->base.base.symbol)) {
4894                         warn_unused_entity(scope->entities, NULL);
4895                 }
4896         }
4897         if (warning.unused_variable) {
4898                 walk_statements(current_function->statement, check_unused_variables,
4899                                 NULL);
4900         }
4901 }
4902
4903 static int determine_truth(expression_t const* const cond)
4904 {
4905         return
4906                 is_constant_expression(cond) != EXPR_CLASS_CONSTANT ? 0 :
4907                 fold_constant_to_bool(cond)                         ? 1 :
4908                 -1;
4909 }
4910
4911 static void check_reachable(statement_t *);
4912 static bool reaches_end;
4913
4914 static bool expression_returns(expression_t const *const expr)
4915 {
4916         switch (expr->kind) {
4917                 case EXPR_CALL: {
4918                         expression_t const *const func = expr->call.function;
4919                         if (func->kind == EXPR_REFERENCE) {
4920                                 entity_t *entity = func->reference.entity;
4921                                 if (entity->kind == ENTITY_FUNCTION
4922                                                 && entity->declaration.modifiers & DM_NORETURN)
4923                                         return false;
4924                         }
4925
4926                         if (!expression_returns(func))
4927                                 return false;
4928
4929                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
4930                                 if (!expression_returns(arg->expression))
4931                                         return false;
4932                         }
4933
4934                         return true;
4935                 }
4936
4937                 case EXPR_REFERENCE:
4938                 case EXPR_REFERENCE_ENUM_VALUE:
4939                 EXPR_LITERAL_CASES
4940                 case EXPR_STRING_LITERAL:
4941                 case EXPR_WIDE_STRING_LITERAL:
4942                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
4943                 case EXPR_LABEL_ADDRESS:
4944                 case EXPR_CLASSIFY_TYPE:
4945                 case EXPR_SIZEOF: // TODO handle obscure VLA case
4946                 case EXPR_ALIGNOF:
4947                 case EXPR_FUNCNAME:
4948                 case EXPR_BUILTIN_CONSTANT_P:
4949                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P:
4950                 case EXPR_OFFSETOF:
4951                 case EXPR_INVALID:
4952                         return true;
4953
4954                 case EXPR_STATEMENT: {
4955                         bool old_reaches_end = reaches_end;
4956                         reaches_end = false;
4957                         check_reachable(expr->statement.statement);
4958                         bool returns = reaches_end;
4959                         reaches_end = old_reaches_end;
4960                         return returns;
4961                 }
4962
4963                 case EXPR_CONDITIONAL:
4964                         // TODO handle constant expression
4965
4966                         if (!expression_returns(expr->conditional.condition))
4967                                 return false;
4968
4969                         if (expr->conditional.true_expression != NULL
4970                                         && expression_returns(expr->conditional.true_expression))
4971                                 return true;
4972
4973                         return expression_returns(expr->conditional.false_expression);
4974
4975                 case EXPR_SELECT:
4976                         return expression_returns(expr->select.compound);
4977
4978                 case EXPR_ARRAY_ACCESS:
4979                         return
4980                                 expression_returns(expr->array_access.array_ref) &&
4981                                 expression_returns(expr->array_access.index);
4982
4983                 case EXPR_VA_START:
4984                         return expression_returns(expr->va_starte.ap);
4985
4986                 case EXPR_VA_ARG:
4987                         return expression_returns(expr->va_arge.ap);
4988
4989                 case EXPR_VA_COPY:
4990                         return expression_returns(expr->va_copye.src);
4991
4992                 EXPR_UNARY_CASES_MANDATORY
4993                         return expression_returns(expr->unary.value);
4994
4995                 case EXPR_UNARY_THROW:
4996                         return false;
4997
4998                 EXPR_BINARY_CASES
4999                         // TODO handle constant lhs of && and ||
5000                         return
5001                                 expression_returns(expr->binary.left) &&
5002                                 expression_returns(expr->binary.right);
5003
5004                 case EXPR_UNKNOWN:
5005                         break;
5006         }
5007
5008         panic("unhandled expression");
5009 }
5010
5011 static bool initializer_returns(initializer_t const *const init)
5012 {
5013         switch (init->kind) {
5014                 case INITIALIZER_VALUE:
5015                         return expression_returns(init->value.value);
5016
5017                 case INITIALIZER_LIST: {
5018                         initializer_t * const*       i       = init->list.initializers;
5019                         initializer_t * const* const end     = i + init->list.len;
5020                         bool                         returns = true;
5021                         for (; i != end; ++i) {
5022                                 if (!initializer_returns(*i))
5023                                         returns = false;
5024                         }
5025                         return returns;
5026                 }
5027
5028                 case INITIALIZER_STRING:
5029                 case INITIALIZER_WIDE_STRING:
5030                 case INITIALIZER_DESIGNATOR: // designators have no payload
5031                         return true;
5032         }
5033         panic("unhandled initializer");
5034 }
5035
5036 static bool noreturn_candidate;
5037
5038 static void check_reachable(statement_t *const stmt)
5039 {
5040         if (stmt->base.reachable)
5041                 return;
5042         if (stmt->kind != STATEMENT_DO_WHILE)
5043                 stmt->base.reachable = true;
5044
5045         statement_t *last = stmt;
5046         statement_t *next;
5047         switch (stmt->kind) {
5048                 case STATEMENT_INVALID:
5049                 case STATEMENT_EMPTY:
5050                 case STATEMENT_ASM:
5051                         next = stmt->base.next;
5052                         break;
5053
5054                 case STATEMENT_DECLARATION: {
5055                         declaration_statement_t const *const decl = &stmt->declaration;
5056                         entity_t                const *      ent  = decl->declarations_begin;
5057                         entity_t                const *const last = decl->declarations_end;
5058                         if (ent != NULL) {
5059                                 for (;; ent = ent->base.next) {
5060                                         if (ent->kind                 == ENTITY_VARIABLE &&
5061                                                         ent->variable.initializer != NULL            &&
5062                                                         !initializer_returns(ent->variable.initializer)) {
5063                                                 return;
5064                                         }
5065                                         if (ent == last)
5066                                                 break;
5067                                 }
5068                         }
5069                         next = stmt->base.next;
5070                         break;
5071                 }
5072
5073                 case STATEMENT_COMPOUND:
5074                         next = stmt->compound.statements;
5075                         if (next == NULL)
5076                                 next = stmt->base.next;
5077                         break;
5078
5079                 case STATEMENT_RETURN: {
5080                         expression_t const *const val = stmt->returns.value;
5081                         if (val == NULL || expression_returns(val))
5082                                 noreturn_candidate = false;
5083                         return;
5084                 }
5085
5086                 case STATEMENT_IF: {
5087                         if_statement_t const *const ifs  = &stmt->ifs;
5088                         expression_t   const *const cond = ifs->condition;
5089
5090                         if (!expression_returns(cond))
5091                                 return;
5092
5093                         int const val = determine_truth(cond);
5094
5095                         if (val >= 0)
5096                                 check_reachable(ifs->true_statement);
5097
5098                         if (val > 0)
5099                                 return;
5100
5101                         if (ifs->false_statement != NULL) {
5102                                 check_reachable(ifs->false_statement);
5103                                 return;
5104                         }
5105
5106                         next = stmt->base.next;
5107                         break;
5108                 }
5109
5110                 case STATEMENT_SWITCH: {
5111                         switch_statement_t const *const switchs = &stmt->switchs;
5112                         expression_t       const *const expr    = switchs->expression;
5113
5114                         if (!expression_returns(expr))
5115                                 return;
5116
5117                         if (is_constant_expression(expr) == EXPR_CLASS_CONSTANT) {
5118                                 long                    const val      = fold_constant_to_int(expr);
5119                                 case_label_statement_t *      defaults = NULL;
5120                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5121                                         if (i->expression == NULL) {
5122                                                 defaults = i;
5123                                                 continue;
5124                                         }
5125
5126                                         if (i->first_case <= val && val <= i->last_case) {
5127                                                 check_reachable((statement_t*)i);
5128                                                 return;
5129                                         }
5130                                 }
5131
5132                                 if (defaults != NULL) {
5133                                         check_reachable((statement_t*)defaults);
5134                                         return;
5135                                 }
5136                         } else {
5137                                 bool has_default = false;
5138                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5139                                         if (i->expression == NULL)
5140                                                 has_default = true;
5141
5142                                         check_reachable((statement_t*)i);
5143                                 }
5144
5145                                 if (has_default)
5146                                         return;
5147                         }
5148
5149                         next = stmt->base.next;
5150                         break;
5151                 }
5152
5153                 case STATEMENT_EXPRESSION: {
5154                         /* Check for noreturn function call */
5155                         expression_t const *const expr = stmt->expression.expression;
5156                         if (!expression_returns(expr))
5157                                 return;
5158
5159                         next = stmt->base.next;
5160                         break;
5161                 }
5162
5163                 case STATEMENT_CONTINUE:
5164                         for (statement_t *parent = stmt;;) {
5165                                 parent = parent->base.parent;
5166                                 if (parent == NULL) /* continue not within loop */
5167                                         return;
5168
5169                                 next = parent;
5170                                 switch (parent->kind) {
5171                                         case STATEMENT_WHILE:    goto continue_while;
5172                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5173                                         case STATEMENT_FOR:      goto continue_for;
5174
5175                                         default: break;
5176                                 }
5177                         }
5178
5179                 case STATEMENT_BREAK:
5180                         for (statement_t *parent = stmt;;) {
5181                                 parent = parent->base.parent;
5182                                 if (parent == NULL) /* break not within loop/switch */
5183                                         return;
5184
5185                                 switch (parent->kind) {
5186                                         case STATEMENT_SWITCH:
5187                                         case STATEMENT_WHILE:
5188                                         case STATEMENT_DO_WHILE:
5189                                         case STATEMENT_FOR:
5190                                                 last = parent;
5191                                                 next = parent->base.next;
5192                                                 goto found_break_parent;
5193
5194                                         default: break;
5195                                 }
5196                         }
5197 found_break_parent:
5198                         break;
5199
5200                 case STATEMENT_GOTO:
5201                         if (stmt->gotos.expression) {
5202                                 if (!expression_returns(stmt->gotos.expression))
5203                                         return;
5204
5205                                 statement_t *parent = stmt->base.parent;
5206                                 if (parent == NULL) /* top level goto */
5207                                         return;
5208                                 next = parent;
5209                         } else {
5210                                 next = stmt->gotos.label->statement;
5211                                 if (next == NULL) /* missing label */
5212                                         return;
5213                         }
5214                         break;
5215
5216                 case STATEMENT_LABEL:
5217                         next = stmt->label.statement;
5218                         break;
5219
5220                 case STATEMENT_CASE_LABEL:
5221                         next = stmt->case_label.statement;
5222                         break;
5223
5224                 case STATEMENT_WHILE: {
5225                         while_statement_t const *const whiles = &stmt->whiles;
5226                         expression_t      const *const cond   = whiles->condition;
5227
5228                         if (!expression_returns(cond))
5229                                 return;
5230
5231                         int const val = determine_truth(cond);
5232
5233                         if (val >= 0)
5234                                 check_reachable(whiles->body);
5235
5236                         if (val > 0)
5237                                 return;
5238
5239                         next = stmt->base.next;
5240                         break;
5241                 }
5242
5243                 case STATEMENT_DO_WHILE:
5244                         next = stmt->do_while.body;
5245                         break;
5246
5247                 case STATEMENT_FOR: {
5248                         for_statement_t *const fors = &stmt->fors;
5249
5250                         if (fors->condition_reachable)
5251                                 return;
5252                         fors->condition_reachable = true;
5253
5254                         expression_t const *const cond = fors->condition;
5255
5256                         int val;
5257                         if (cond == NULL) {
5258                                 val = 1;
5259                         } else if (expression_returns(cond)) {
5260                                 val = determine_truth(cond);
5261                         } else {
5262                                 return;
5263                         }
5264
5265                         if (val >= 0)
5266                                 check_reachable(fors->body);
5267
5268                         if (val > 0)
5269                                 return;
5270
5271                         next = stmt->base.next;
5272                         break;
5273                 }
5274
5275                 case STATEMENT_MS_TRY: {
5276                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5277                         check_reachable(ms_try->try_statement);
5278                         next = ms_try->final_statement;
5279                         break;
5280                 }
5281
5282                 case STATEMENT_LEAVE: {
5283                         statement_t *parent = stmt;
5284                         for (;;) {
5285                                 parent = parent->base.parent;
5286                                 if (parent == NULL) /* __leave not within __try */
5287                                         return;
5288
5289                                 if (parent->kind == STATEMENT_MS_TRY) {
5290                                         last = parent;
5291                                         next = parent->ms_try.final_statement;
5292                                         break;
5293                                 }
5294                         }
5295                         break;
5296                 }
5297
5298                 default:
5299                         panic("invalid statement kind");
5300         }
5301
5302         while (next == NULL) {
5303                 next = last->base.parent;
5304                 if (next == NULL) {
5305                         noreturn_candidate = false;
5306
5307                         type_t *const type = skip_typeref(current_function->base.type);
5308                         assert(is_type_function(type));
5309                         type_t *const ret  = skip_typeref(type->function.return_type);
5310                         if (warning.return_type                    &&
5311                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
5312                             is_type_valid(ret)                     &&
5313                             !is_sym_main(current_function->base.base.symbol)) {
5314                                 warningf(&stmt->base.source_position,
5315                                          "control reaches end of non-void function");
5316                         }
5317                         return;
5318                 }
5319
5320                 switch (next->kind) {
5321                         case STATEMENT_INVALID:
5322                         case STATEMENT_EMPTY:
5323                         case STATEMENT_DECLARATION:
5324                         case STATEMENT_EXPRESSION:
5325                         case STATEMENT_ASM:
5326                         case STATEMENT_RETURN:
5327                         case STATEMENT_CONTINUE:
5328                         case STATEMENT_BREAK:
5329                         case STATEMENT_GOTO:
5330                         case STATEMENT_LEAVE:
5331                                 panic("invalid control flow in function");
5332
5333                         case STATEMENT_COMPOUND:
5334                                 if (next->compound.stmt_expr) {
5335                                         reaches_end = true;
5336                                         return;
5337                                 }
5338                                 /* FALLTHROUGH */
5339                         case STATEMENT_IF:
5340                         case STATEMENT_SWITCH:
5341                         case STATEMENT_LABEL:
5342                         case STATEMENT_CASE_LABEL:
5343                                 last = next;
5344                                 next = next->base.next;
5345                                 break;
5346
5347                         case STATEMENT_WHILE: {
5348 continue_while:
5349                                 if (next->base.reachable)
5350                                         return;
5351                                 next->base.reachable = true;
5352
5353                                 while_statement_t const *const whiles = &next->whiles;
5354                                 expression_t      const *const cond   = whiles->condition;
5355
5356                                 if (!expression_returns(cond))
5357                                         return;
5358
5359                                 int const val = determine_truth(cond);
5360
5361                                 if (val >= 0)
5362                                         check_reachable(whiles->body);
5363
5364                                 if (val > 0)
5365                                         return;
5366
5367                                 last = next;
5368                                 next = next->base.next;
5369                                 break;
5370                         }
5371
5372                         case STATEMENT_DO_WHILE: {
5373 continue_do_while:
5374                                 if (next->base.reachable)
5375                                         return;
5376                                 next->base.reachable = true;
5377
5378                                 do_while_statement_t const *const dw   = &next->do_while;
5379                                 expression_t         const *const cond = dw->condition;
5380
5381                                 if (!expression_returns(cond))
5382                                         return;
5383
5384                                 int const val = determine_truth(cond);
5385
5386                                 if (val >= 0)
5387                                         check_reachable(dw->body);
5388
5389                                 if (val > 0)
5390                                         return;
5391
5392                                 last = next;
5393                                 next = next->base.next;
5394                                 break;
5395                         }
5396
5397                         case STATEMENT_FOR: {
5398 continue_for:;
5399                                 for_statement_t *const fors = &next->fors;
5400
5401                                 fors->step_reachable = true;
5402
5403                                 if (fors->condition_reachable)
5404                                         return;
5405                                 fors->condition_reachable = true;
5406
5407                                 expression_t const *const cond = fors->condition;
5408
5409                                 int val;
5410                                 if (cond == NULL) {
5411                                         val = 1;
5412                                 } else if (expression_returns(cond)) {
5413                                         val = determine_truth(cond);
5414                                 } else {
5415                                         return;
5416                                 }
5417
5418                                 if (val >= 0)
5419                                         check_reachable(fors->body);
5420
5421                                 if (val > 0)
5422                                         return;
5423
5424                                 last = next;
5425                                 next = next->base.next;
5426                                 break;
5427                         }
5428
5429                         case STATEMENT_MS_TRY:
5430                                 last = next;
5431                                 next = next->ms_try.final_statement;
5432                                 break;
5433                 }
5434         }
5435
5436         check_reachable(next);
5437 }
5438
5439 static void check_unreachable(statement_t* const stmt, void *const env)
5440 {
5441         (void)env;
5442
5443         switch (stmt->kind) {
5444                 case STATEMENT_DO_WHILE:
5445                         if (!stmt->base.reachable) {
5446                                 expression_t const *const cond = stmt->do_while.condition;
5447                                 if (determine_truth(cond) >= 0) {
5448                                         warningf(&cond->base.source_position,
5449                                                  "condition of do-while-loop is unreachable");
5450                                 }
5451                         }
5452                         return;
5453
5454                 case STATEMENT_FOR: {
5455                         for_statement_t const* const fors = &stmt->fors;
5456
5457                         // if init and step are unreachable, cond is unreachable, too
5458                         if (!stmt->base.reachable && !fors->step_reachable) {
5459                                 warningf(&stmt->base.source_position, "statement is unreachable");
5460                         } else {
5461                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5462                                         warningf(&fors->initialisation->base.source_position,
5463                                                  "initialisation of for-statement is unreachable");
5464                                 }
5465
5466                                 if (!fors->condition_reachable && fors->condition != NULL) {
5467                                         warningf(&fors->condition->base.source_position,
5468                                                  "condition of for-statement is unreachable");
5469                                 }
5470
5471                                 if (!fors->step_reachable && fors->step != NULL) {
5472                                         warningf(&fors->step->base.source_position,
5473                                                  "step of for-statement is unreachable");
5474                                 }
5475                         }
5476                         return;
5477                 }
5478
5479                 case STATEMENT_COMPOUND:
5480                         if (stmt->compound.statements != NULL)
5481                                 return;
5482                         goto warn_unreachable;
5483
5484                 case STATEMENT_DECLARATION: {
5485                         /* Only warn if there is at least one declarator with an initializer.
5486                          * This typically occurs in switch statements. */
5487                         declaration_statement_t const *const decl = &stmt->declaration;
5488                         entity_t                const *      ent  = decl->declarations_begin;
5489                         entity_t                const *const last = decl->declarations_end;
5490                         if (ent != NULL) {
5491                                 for (;; ent = ent->base.next) {
5492                                         if (ent->kind                 == ENTITY_VARIABLE &&
5493                                                         ent->variable.initializer != NULL) {
5494                                                 goto warn_unreachable;
5495                                         }
5496                                         if (ent == last)
5497                                                 return;
5498                                 }
5499                         }
5500                 }
5501
5502                 default:
5503 warn_unreachable:
5504                         if (!stmt->base.reachable)
5505                                 warningf(&stmt->base.source_position, "statement is unreachable");
5506                         return;
5507         }
5508 }
5509
5510 static void parse_external_declaration(void)
5511 {
5512         /* function-definitions and declarations both start with declaration
5513          * specifiers */
5514         declaration_specifiers_t specifiers;
5515         memset(&specifiers, 0, sizeof(specifiers));
5516
5517         add_anchor_token(';');
5518         parse_declaration_specifiers(&specifiers);
5519         rem_anchor_token(';');
5520
5521         /* must be a declaration */
5522         if (token.type == ';') {
5523                 parse_anonymous_declaration_rest(&specifiers);
5524                 return;
5525         }
5526
5527         add_anchor_token(',');
5528         add_anchor_token('=');
5529         add_anchor_token(';');
5530         add_anchor_token('{');
5531
5532         /* declarator is common to both function-definitions and declarations */
5533         entity_t *ndeclaration = parse_declarator(&specifiers, DECL_FLAGS_NONE);
5534
5535         rem_anchor_token('{');
5536         rem_anchor_token(';');
5537         rem_anchor_token('=');
5538         rem_anchor_token(',');
5539
5540         /* must be a declaration */
5541         switch (token.type) {
5542                 case ',':
5543                 case ';':
5544                 case '=':
5545                         parse_declaration_rest(ndeclaration, &specifiers, record_entity,
5546                                         DECL_FLAGS_NONE);
5547                         return;
5548         }
5549
5550         /* must be a function definition */
5551         parse_kr_declaration_list(ndeclaration);
5552
5553         if (token.type != '{') {
5554                 parse_error_expected("while parsing function definition", '{', NULL);
5555                 eat_until_matching_token(';');
5556                 return;
5557         }
5558
5559         assert(is_declaration(ndeclaration));
5560         type_t *const orig_type = ndeclaration->declaration.type;
5561         type_t *      type      = skip_typeref(orig_type);
5562
5563         if (!is_type_function(type)) {
5564                 if (is_type_valid(type)) {
5565                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5566                                type, ndeclaration->base.symbol);
5567                 }
5568                 eat_block();
5569                 return;
5570         } else if (is_typeref(orig_type)) {
5571                 /* §6.9.1:2 */
5572                 errorf(&ndeclaration->base.source_position,
5573                                 "type of function definition '%#T' is a typedef",
5574                                 orig_type, ndeclaration->base.symbol);
5575         }
5576
5577         if (warning.aggregate_return &&
5578             is_type_compound(skip_typeref(type->function.return_type))) {
5579                 warningf(HERE, "function '%Y' returns an aggregate",
5580                          ndeclaration->base.symbol);
5581         }
5582         if (warning.traditional && !type->function.unspecified_parameters) {
5583                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
5584                         ndeclaration->base.symbol);
5585         }
5586         if (warning.old_style_definition && type->function.unspecified_parameters) {
5587                 warningf(HERE, "old-style function definition '%Y'",
5588                         ndeclaration->base.symbol);
5589         }
5590
5591         /* §6.7.5.3:14 a function definition with () means no
5592          * parameters (and not unspecified parameters) */
5593         if (type->function.unspecified_parameters &&
5594                         type->function.parameters == NULL) {
5595                 type_t *copy                          = duplicate_type(type);
5596                 copy->function.unspecified_parameters = false;
5597                 type                                  = identify_new_type(copy);
5598
5599                 ndeclaration->declaration.type = type;
5600         }
5601
5602         entity_t *const entity = record_entity(ndeclaration, true);
5603         assert(entity->kind == ENTITY_FUNCTION);
5604         assert(ndeclaration->kind == ENTITY_FUNCTION);
5605
5606         function_t *const function = &entity->function;
5607         if (ndeclaration != entity) {
5608                 function->parameters = ndeclaration->function.parameters;
5609         }
5610         assert(is_declaration(entity));
5611         type = skip_typeref(entity->declaration.type);
5612
5613         /* push function parameters and switch scope */
5614         size_t const  top       = environment_top();
5615         scope_t      *old_scope = scope_push(&function->parameters);
5616
5617         entity_t *parameter = function->parameters.entities;
5618         for (; parameter != NULL; parameter = parameter->base.next) {
5619                 if (parameter->base.parent_scope == &ndeclaration->function.parameters) {
5620                         parameter->base.parent_scope = current_scope;
5621                 }
5622                 assert(parameter->base.parent_scope == NULL
5623                                 || parameter->base.parent_scope == current_scope);
5624                 parameter->base.parent_scope = current_scope;
5625                 if (parameter->base.symbol == NULL) {
5626                         errorf(&parameter->base.source_position, "parameter name omitted");
5627                         continue;
5628                 }
5629                 environment_push(parameter);
5630         }
5631
5632         if (function->statement != NULL) {
5633                 parser_error_multiple_definition(entity, HERE);
5634                 eat_block();
5635         } else {
5636                 /* parse function body */
5637                 int         label_stack_top      = label_top();
5638                 function_t *old_current_function = current_function;
5639                 entity_t   *old_current_entity   = current_entity;
5640                 current_function                 = function;
5641                 current_entity                   = entity;
5642                 current_parent                   = NULL;
5643
5644                 goto_first   = NULL;
5645                 goto_anchor  = &goto_first;
5646                 label_first  = NULL;
5647                 label_anchor = &label_first;
5648
5649                 statement_t *const body = parse_compound_statement(false);
5650                 function->statement = body;
5651                 first_err = true;
5652                 check_labels();
5653                 check_declarations();
5654                 if (warning.return_type      ||
5655                     warning.unreachable_code ||
5656                     (warning.missing_noreturn
5657                      && !(function->base.modifiers & DM_NORETURN))) {
5658                         noreturn_candidate = true;
5659                         check_reachable(body);
5660                         if (warning.unreachable_code)
5661                                 walk_statements(body, check_unreachable, NULL);
5662                         if (warning.missing_noreturn &&
5663                             noreturn_candidate       &&
5664                             !(function->base.modifiers & DM_NORETURN)) {
5665                                 warningf(&body->base.source_position,
5666                                          "function '%#T' is candidate for attribute 'noreturn'",
5667                                          type, entity->base.symbol);
5668                         }
5669                 }
5670
5671                 assert(current_parent   == NULL);
5672                 assert(current_function == function);
5673                 assert(current_entity   == entity);
5674                 current_entity   = old_current_entity;
5675                 current_function = old_current_function;
5676                 label_pop_to(label_stack_top);
5677         }
5678
5679         assert(current_scope == &function->parameters);
5680         scope_pop(old_scope);
5681         environment_pop_to(top);
5682 }
5683
5684 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5685                                   source_position_t *source_position,
5686                                   const symbol_t *symbol)
5687 {
5688         type_t *type = allocate_type_zero(TYPE_BITFIELD);
5689
5690         type->bitfield.base_type       = base_type;
5691         type->bitfield.size_expression = size;
5692
5693         il_size_t bit_size;
5694         type_t *skipped_type = skip_typeref(base_type);
5695         if (!is_type_integer(skipped_type)) {
5696                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5697                        base_type);
5698                 bit_size = 0;
5699         } else {
5700                 bit_size = get_type_size(base_type) * 8;
5701         }
5702
5703         if (is_constant_expression(size) == EXPR_CLASS_CONSTANT) {
5704                 long v = fold_constant_to_int(size);
5705                 const symbol_t *user_symbol = symbol == NULL ? sym_anonymous : symbol;
5706
5707                 if (v < 0) {
5708                         errorf(source_position, "negative width in bit-field '%Y'",
5709                                user_symbol);
5710                 } else if (v == 0 && symbol != NULL) {
5711                         errorf(source_position, "zero width for bit-field '%Y'",
5712                                user_symbol);
5713                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
5714                         errorf(source_position, "width of '%Y' exceeds its type",
5715                                user_symbol);
5716                 } else {
5717                         type->bitfield.bit_size = v;
5718                 }
5719         }
5720
5721         return type;
5722 }
5723
5724 static entity_t *find_compound_entry(compound_t *compound, symbol_t *symbol)
5725 {
5726         entity_t *iter = compound->members.entities;
5727         for (; iter != NULL; iter = iter->base.next) {
5728                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
5729                         continue;
5730
5731                 if (iter->base.symbol == symbol) {
5732                         return iter;
5733                 } else if (iter->base.symbol == NULL) {
5734                         /* search in anonymous structs and unions */
5735                         type_t *type = skip_typeref(iter->declaration.type);
5736                         if (is_type_compound(type)) {
5737                                 if (find_compound_entry(type->compound.compound, symbol)
5738                                                 != NULL)
5739                                         return iter;
5740                         }
5741                         continue;
5742                 }
5743         }
5744
5745         return NULL;
5746 }
5747
5748 static void check_deprecated(const source_position_t *source_position,
5749                              const entity_t *entity)
5750 {
5751         if (!warning.deprecated_declarations)
5752                 return;
5753         if (!is_declaration(entity))
5754                 return;
5755         if ((entity->declaration.modifiers & DM_DEPRECATED) == 0)
5756                 return;
5757
5758         char const *const prefix = get_entity_kind_name(entity->kind);
5759         const char *deprecated_string
5760                         = get_deprecated_string(entity->declaration.attributes);
5761         if (deprecated_string != NULL) {
5762                 warningf(source_position, "%s '%Y' is deprecated (declared %P): \"%s\"",
5763                                  prefix, entity->base.symbol, &entity->base.source_position,
5764                                  deprecated_string);
5765         } else {
5766                 warningf(source_position, "%s '%Y' is deprecated (declared %P)", prefix,
5767                                  entity->base.symbol, &entity->base.source_position);
5768         }
5769 }
5770
5771
5772 static expression_t *create_select(const source_position_t *pos,
5773                                    expression_t *addr,
5774                                    type_qualifiers_t qualifiers,
5775                                                                    entity_t *entry)
5776 {
5777         assert(entry->kind == ENTITY_COMPOUND_MEMBER);
5778
5779         check_deprecated(pos, entry);
5780
5781         expression_t *select          = allocate_expression_zero(EXPR_SELECT);
5782         select->select.compound       = addr;
5783         select->select.compound_entry = entry;
5784
5785         type_t *entry_type = entry->declaration.type;
5786         type_t *res_type   = get_qualified_type(entry_type, qualifiers);
5787
5788         /* we always do the auto-type conversions; the & and sizeof parser contains
5789          * code to revert this! */
5790         select->base.type = automatic_type_conversion(res_type);
5791         if (res_type->kind == TYPE_BITFIELD) {
5792                 select->base.type = res_type->bitfield.base_type;
5793         }
5794
5795         return select;
5796 }
5797
5798 /**
5799  * Find entry with symbol in compound. Search anonymous structs and unions and
5800  * creates implicit select expressions for them.
5801  * Returns the adress for the innermost compound.
5802  */
5803 static expression_t *find_create_select(const source_position_t *pos,
5804                                         expression_t *addr,
5805                                         type_qualifiers_t qualifiers,
5806                                         compound_t *compound, symbol_t *symbol)
5807 {
5808         entity_t *iter = compound->members.entities;
5809         for (; iter != NULL; iter = iter->base.next) {
5810                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
5811                         continue;
5812
5813                 symbol_t *iter_symbol = iter->base.symbol;
5814                 if (iter_symbol == NULL) {
5815                         type_t *type = iter->declaration.type;
5816                         if (type->kind != TYPE_COMPOUND_STRUCT
5817                                         && type->kind != TYPE_COMPOUND_UNION)
5818                                 continue;
5819
5820                         compound_t *sub_compound = type->compound.compound;
5821
5822                         if (find_compound_entry(sub_compound, symbol) == NULL)
5823                                 continue;
5824
5825                         expression_t *sub_addr = create_select(pos, addr, qualifiers, iter);
5826                         sub_addr->base.source_position = *pos;
5827                         sub_addr->select.implicit      = true;
5828                         return find_create_select(pos, sub_addr, qualifiers, sub_compound,
5829                                                   symbol);
5830                 }
5831
5832                 if (iter_symbol == symbol) {
5833                         return create_select(pos, addr, qualifiers, iter);
5834                 }
5835         }
5836
5837         return NULL;
5838 }
5839
5840 static void parse_compound_declarators(compound_t *compound,
5841                 const declaration_specifiers_t *specifiers)
5842 {
5843         do {
5844                 entity_t *entity;
5845
5846                 if (token.type == ':') {
5847                         source_position_t source_position = *HERE;
5848                         next_token();
5849
5850                         type_t *base_type = specifiers->type;
5851                         expression_t *size = parse_constant_expression();
5852
5853                         type_t *type = make_bitfield_type(base_type, size,
5854                                         &source_position, NULL);
5855
5856                         attribute_t  *attributes = parse_attributes(NULL);
5857                         attribute_t **anchor     = &attributes;
5858                         while (*anchor != NULL)
5859                                 anchor = &(*anchor)->next;
5860                         *anchor = specifiers->attributes;
5861
5862                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
5863                         entity->base.namespc                       = NAMESPACE_NORMAL;
5864                         entity->base.source_position               = source_position;
5865                         entity->declaration.declared_storage_class = STORAGE_CLASS_NONE;
5866                         entity->declaration.storage_class          = STORAGE_CLASS_NONE;
5867                         entity->declaration.type                   = type;
5868                         entity->declaration.attributes             = attributes;
5869
5870                         if (attributes != NULL) {
5871                                 handle_entity_attributes(attributes, entity);
5872                         }
5873                         append_entity(&compound->members, entity);
5874                 } else {
5875                         entity = parse_declarator(specifiers,
5876                                         DECL_MAY_BE_ABSTRACT | DECL_CREATE_COMPOUND_MEMBER);
5877                         if (entity->kind == ENTITY_TYPEDEF) {
5878                                 errorf(&entity->base.source_position,
5879                                                 "typedef not allowed as compound member");
5880                         } else {
5881                                 assert(entity->kind == ENTITY_COMPOUND_MEMBER);
5882
5883                                 /* make sure we don't define a symbol multiple times */
5884                                 symbol_t *symbol = entity->base.symbol;
5885                                 if (symbol != NULL) {
5886                                         entity_t *prev = find_compound_entry(compound, symbol);
5887                                         if (prev != NULL) {
5888                                                 errorf(&entity->base.source_position,
5889                                                                 "multiple declarations of symbol '%Y' (declared %P)",
5890                                                                 symbol, &prev->base.source_position);
5891                                         }
5892                                 }
5893
5894                                 if (token.type == ':') {
5895                                         source_position_t source_position = *HERE;
5896                                         next_token();
5897                                         expression_t *size = parse_constant_expression();
5898
5899                                         type_t *type          = entity->declaration.type;
5900                                         type_t *bitfield_type = make_bitfield_type(type, size,
5901                                                         &source_position, entity->base.symbol);
5902
5903                                         attribute_t *attributes = parse_attributes(NULL);
5904                                         entity->declaration.type = bitfield_type;
5905                                         handle_entity_attributes(attributes, entity);
5906                                 } else {
5907                                         type_t *orig_type = entity->declaration.type;
5908                                         type_t *type      = skip_typeref(orig_type);
5909                                         if (is_type_function(type)) {
5910                                                 errorf(&entity->base.source_position,
5911                                                        "compound member '%Y' must not have function type '%T'",
5912                                                                 entity->base.symbol, orig_type);
5913                                         } else if (is_type_incomplete(type)) {
5914                                                 /* §6.7.2.1:16 flexible array member */
5915                                                 if (!is_type_array(type)       ||
5916                                                                 token.type          != ';' ||
5917                                                                 look_ahead(1)->type != '}') {
5918                                                         errorf(&entity->base.source_position,
5919                                                                "compound member '%Y' has incomplete type '%T'",
5920                                                                         entity->base.symbol, orig_type);
5921                                                 }
5922                                         }
5923                                 }
5924
5925                                 append_entity(&compound->members, entity);
5926                         }
5927                 }
5928         } while (next_if(','));
5929         expect(';', end_error);
5930
5931 end_error:
5932         anonymous_entity = NULL;
5933 }
5934
5935 static void parse_compound_type_entries(compound_t *compound)
5936 {
5937         eat('{');
5938         add_anchor_token('}');
5939
5940         while (token.type != '}') {
5941                 if (token.type == T_EOF) {
5942                         errorf(HERE, "EOF while parsing struct");
5943                         break;
5944                 }
5945                 declaration_specifiers_t specifiers;
5946                 memset(&specifiers, 0, sizeof(specifiers));
5947                 parse_declaration_specifiers(&specifiers);
5948
5949                 parse_compound_declarators(compound, &specifiers);
5950         }
5951         rem_anchor_token('}');
5952         next_token();
5953
5954         /* §6.7.2.1:7 */
5955         compound->complete = true;
5956 }
5957
5958 static type_t *parse_typename(void)
5959 {
5960         declaration_specifiers_t specifiers;
5961         memset(&specifiers, 0, sizeof(specifiers));
5962         parse_declaration_specifiers(&specifiers);
5963         if (specifiers.storage_class != STORAGE_CLASS_NONE
5964                         || specifiers.thread_local) {
5965                 /* TODO: improve error message, user does probably not know what a
5966                  * storage class is...
5967                  */
5968                 errorf(HERE, "typename must not have a storage class");
5969         }
5970
5971         type_t *result = parse_abstract_declarator(specifiers.type);
5972
5973         return result;
5974 }
5975
5976
5977
5978
5979 typedef expression_t* (*parse_expression_function)(void);
5980 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
5981
5982 typedef struct expression_parser_function_t expression_parser_function_t;
5983 struct expression_parser_function_t {
5984         parse_expression_function        parser;
5985         precedence_t                     infix_precedence;
5986         parse_expression_infix_function  infix_parser;
5987 };
5988
5989 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5990
5991 /**
5992  * Prints an error message if an expression was expected but not read
5993  */
5994 static expression_t *expected_expression_error(void)
5995 {
5996         /* skip the error message if the error token was read */
5997         if (token.type != T_ERROR) {
5998                 errorf(HERE, "expected expression, got token %K", &token);
5999         }
6000         next_token();
6001
6002         return create_invalid_expression();
6003 }
6004
6005 static type_t *get_string_type(void)
6006 {
6007         return warning.write_strings ? type_const_char_ptr : type_char_ptr;
6008 }
6009
6010 static type_t *get_wide_string_type(void)
6011 {
6012         return warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
6013 }
6014
6015 /**
6016  * Parse a string constant.
6017  */
6018 static expression_t *parse_string_literal(void)
6019 {
6020         source_position_t begin   = token.source_position;
6021         string_t          res     = token.literal;
6022         bool              is_wide = (token.type == T_WIDE_STRING_LITERAL);
6023
6024         next_token();
6025         while (token.type == T_STRING_LITERAL
6026                         || token.type == T_WIDE_STRING_LITERAL) {
6027                 warn_string_concat(&token.source_position);
6028                 res = concat_strings(&res, &token.literal);
6029                 next_token();
6030                 is_wide |= token.type == T_WIDE_STRING_LITERAL;
6031         }
6032
6033         expression_t *literal;
6034         if (is_wide) {
6035                 literal = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6036                 literal->base.type = get_wide_string_type();
6037         } else {
6038                 literal = allocate_expression_zero(EXPR_STRING_LITERAL);
6039                 literal->base.type = get_string_type();
6040         }
6041         literal->base.source_position = begin;
6042         literal->literal.value        = res;
6043
6044         return literal;
6045 }
6046
6047 /**
6048  * Parse a boolean constant.
6049  */
6050 static expression_t *parse_boolean_literal(bool value)
6051 {
6052         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_BOOLEAN);
6053         literal->base.source_position = token.source_position;
6054         literal->base.type            = type_bool;
6055         literal->literal.value.begin  = value ? "true" : "false";
6056         literal->literal.value.size   = value ? 4 : 5;
6057
6058         next_token();
6059         return literal;
6060 }
6061
6062 static void warn_traditional_suffix(void)
6063 {
6064         if (!warning.traditional)
6065                 return;
6066         warningf(&token.source_position, "traditional C rejects the '%Y' suffix",
6067                  token.symbol);
6068 }
6069
6070 static void check_integer_suffix(void)
6071 {
6072         symbol_t *suffix = token.symbol;
6073         if (suffix == NULL)
6074                 return;
6075
6076         bool not_traditional = false;
6077         const char *c = suffix->string;
6078         if (*c == 'l' || *c == 'L') {
6079                 ++c;
6080                 if (*c == *(c-1)) {
6081                         not_traditional = true;
6082                         ++c;
6083                         if (*c == 'u' || *c == 'U') {
6084                                 ++c;
6085                         }
6086                 } else if (*c == 'u' || *c == 'U') {
6087                         not_traditional = true;
6088                         ++c;
6089                 }
6090         } else if (*c == 'u' || *c == 'U') {
6091                 not_traditional = true;
6092                 ++c;
6093                 if (*c == 'l' || *c == 'L') {
6094                         ++c;
6095                         if (*c == *(c-1)) {
6096                                 ++c;
6097                         }
6098                 }
6099         }
6100         if (*c != '\0') {
6101                 errorf(&token.source_position,
6102                        "invalid suffix '%s' on integer constant", suffix->string);
6103         } else if (not_traditional) {
6104                 warn_traditional_suffix();
6105         }
6106 }
6107
6108 static type_t *check_floatingpoint_suffix(void)
6109 {
6110         symbol_t *suffix = token.symbol;
6111         type_t   *type   = type_double;
6112         if (suffix == NULL)
6113                 return type;
6114
6115         bool not_traditional = false;
6116         const char *c = suffix->string;
6117         if (*c == 'f' || *c == 'F') {
6118                 ++c;
6119                 type = type_float;
6120         } else if (*c == 'l' || *c == 'L') {
6121                 ++c;
6122                 type = type_long_double;
6123         }
6124         if (*c != '\0') {
6125                 errorf(&token.source_position,
6126                        "invalid suffix '%s' on floatingpoint constant", suffix->string);
6127         } else if (not_traditional) {
6128                 warn_traditional_suffix();
6129         }
6130
6131         return type;
6132 }
6133
6134 /**
6135  * Parse an integer constant.
6136  */
6137 static expression_t *parse_number_literal(void)
6138 {
6139         expression_kind_t  kind;
6140         type_t            *type;
6141
6142         switch (token.type) {
6143         case T_INTEGER:
6144                 kind = EXPR_LITERAL_INTEGER;
6145                 check_integer_suffix();
6146                 type = type_int;
6147                 break;
6148         case T_INTEGER_OCTAL:
6149                 kind = EXPR_LITERAL_INTEGER_OCTAL;
6150                 check_integer_suffix();
6151                 type = type_int;
6152                 break;
6153         case T_INTEGER_HEXADECIMAL:
6154                 kind = EXPR_LITERAL_INTEGER_HEXADECIMAL;
6155                 check_integer_suffix();
6156                 type = type_int;
6157                 break;
6158         case T_FLOATINGPOINT:
6159                 kind = EXPR_LITERAL_FLOATINGPOINT;
6160                 type = check_floatingpoint_suffix();
6161                 break;
6162         case T_FLOATINGPOINT_HEXADECIMAL:
6163                 kind = EXPR_LITERAL_FLOATINGPOINT_HEXADECIMAL;
6164                 type = check_floatingpoint_suffix();
6165                 break;
6166         default:
6167                 panic("unexpected token type in parse_number_literal");
6168         }
6169
6170         expression_t *literal = allocate_expression_zero(kind);
6171         literal->base.source_position = token.source_position;
6172         literal->base.type            = type;
6173         literal->literal.value        = token.literal;
6174         literal->literal.suffix       = token.symbol;
6175         next_token();
6176
6177         /* integer type depends on the size of the number and the size
6178          * representable by the types. The backend/codegeneration has to determine
6179          * that
6180          */
6181         determine_literal_type(&literal->literal);
6182         return literal;
6183 }
6184
6185 /**
6186  * Parse a character constant.
6187  */
6188 static expression_t *parse_character_constant(void)
6189 {
6190         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_CHARACTER);
6191         literal->base.source_position = token.source_position;
6192         literal->base.type            = c_mode & _CXX ? type_char : type_int;
6193         literal->literal.value        = token.literal;
6194
6195         size_t len = literal->literal.value.size;
6196         if (len != 1) {
6197                 if (!GNU_MODE && !(c_mode & _C99)) {
6198                         errorf(HERE, "more than 1 character in character constant");
6199                 } else if (warning.multichar) {
6200                         literal->base.type = type_int;
6201                         warningf(HERE, "multi-character character constant");
6202                 }
6203         }
6204
6205         next_token();
6206         return literal;
6207 }
6208
6209 /**
6210  * Parse a wide character constant.
6211  */
6212 static expression_t *parse_wide_character_constant(void)
6213 {
6214         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_WIDE_CHARACTER);
6215         literal->base.source_position = token.source_position;
6216         literal->base.type            = type_int;
6217         literal->literal.value        = token.literal;
6218
6219         size_t len = wstrlen(&literal->literal.value);
6220         if (len != 1) {
6221                 warningf(HERE, "multi-character character constant");
6222         }
6223
6224         next_token();
6225         return literal;
6226 }
6227
6228 static entity_t *create_implicit_function(symbol_t *symbol,
6229                 const source_position_t *source_position)
6230 {
6231         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6232         ntype->function.return_type            = type_int;
6233         ntype->function.unspecified_parameters = true;
6234         ntype->function.linkage                = LINKAGE_C;
6235         type_t *type                           = identify_new_type(ntype);
6236
6237         entity_t *entity = allocate_entity_zero(ENTITY_FUNCTION);
6238         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
6239         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
6240         entity->declaration.type                   = type;
6241         entity->declaration.implicit               = true;
6242         entity->base.namespc                       = NAMESPACE_NORMAL;
6243         entity->base.symbol                        = symbol;
6244         entity->base.source_position               = *source_position;
6245
6246         if (current_scope != NULL) {
6247                 bool strict_prototypes_old = warning.strict_prototypes;
6248                 warning.strict_prototypes  = false;
6249                 record_entity(entity, false);
6250                 warning.strict_prototypes = strict_prototypes_old;
6251         }
6252
6253         return entity;
6254 }
6255
6256 /**
6257  * Performs automatic type cast as described in §6.3.2.1.
6258  *
6259  * @param orig_type  the original type
6260  */
6261 static type_t *automatic_type_conversion(type_t *orig_type)
6262 {
6263         type_t *type = skip_typeref(orig_type);
6264         if (is_type_array(type)) {
6265                 array_type_t *array_type   = &type->array;
6266                 type_t       *element_type = array_type->element_type;
6267                 unsigned      qualifiers   = array_type->base.qualifiers;
6268
6269                 return make_pointer_type(element_type, qualifiers);
6270         }
6271
6272         if (is_type_function(type)) {
6273                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6274         }
6275
6276         return orig_type;
6277 }
6278
6279 /**
6280  * reverts the automatic casts of array to pointer types and function
6281  * to function-pointer types as defined §6.3.2.1
6282  */
6283 type_t *revert_automatic_type_conversion(const expression_t *expression)
6284 {
6285         switch (expression->kind) {
6286         case EXPR_REFERENCE: {
6287                 entity_t *entity = expression->reference.entity;
6288                 if (is_declaration(entity)) {
6289                         return entity->declaration.type;
6290                 } else if (entity->kind == ENTITY_ENUM_VALUE) {
6291                         return entity->enum_value.enum_type;
6292                 } else {
6293                         panic("no declaration or enum in reference");
6294                 }
6295         }
6296
6297         case EXPR_SELECT: {
6298                 entity_t *entity = expression->select.compound_entry;
6299                 assert(is_declaration(entity));
6300                 type_t   *type   = entity->declaration.type;
6301                 return get_qualified_type(type,
6302                                 expression->base.type->base.qualifiers);
6303         }
6304
6305         case EXPR_UNARY_DEREFERENCE: {
6306                 const expression_t *const value = expression->unary.value;
6307                 type_t             *const type  = skip_typeref(value->base.type);
6308                 if (!is_type_pointer(type))
6309                         return type_error_type;
6310                 return type->pointer.points_to;
6311         }
6312
6313         case EXPR_ARRAY_ACCESS: {
6314                 const expression_t *array_ref = expression->array_access.array_ref;
6315                 type_t             *type_left = skip_typeref(array_ref->base.type);
6316                 if (!is_type_pointer(type_left))
6317                         return type_error_type;
6318                 return type_left->pointer.points_to;
6319         }
6320
6321         case EXPR_STRING_LITERAL: {
6322                 size_t size = expression->string_literal.value.size;
6323                 return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6324         }
6325
6326         case EXPR_WIDE_STRING_LITERAL: {
6327                 size_t size = wstrlen(&expression->string_literal.value);
6328                 return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6329         }
6330
6331         case EXPR_COMPOUND_LITERAL:
6332                 return expression->compound_literal.type;
6333
6334         default:
6335                 break;
6336         }
6337         return expression->base.type;
6338 }
6339
6340 /**
6341  * Find an entity matching a symbol in a scope.
6342  * Uses current scope if scope is NULL
6343  */
6344 static entity_t *lookup_entity(const scope_t *scope, symbol_t *symbol,
6345                                namespace_tag_t namespc)
6346 {
6347         if (scope == NULL) {
6348                 return get_entity(symbol, namespc);
6349         }
6350
6351         /* we should optimize here, if scope grows above a certain size we should
6352            construct a hashmap here... */
6353         entity_t *entity = scope->entities;
6354         for ( ; entity != NULL; entity = entity->base.next) {
6355                 if (entity->base.symbol == symbol && entity->base.namespc == namespc)
6356                         break;
6357         }
6358
6359         return entity;
6360 }
6361
6362 static entity_t *parse_qualified_identifier(void)
6363 {
6364         /* namespace containing the symbol */
6365         symbol_t          *symbol;
6366         source_position_t  pos;
6367         const scope_t     *lookup_scope = NULL;
6368
6369         if (next_if(T_COLONCOLON))
6370                 lookup_scope = &unit->scope;
6371
6372         entity_t *entity;
6373         while (true) {
6374                 if (token.type != T_IDENTIFIER) {
6375                         parse_error_expected("while parsing identifier", T_IDENTIFIER, NULL);
6376                         return create_error_entity(sym_anonymous, ENTITY_VARIABLE);
6377                 }
6378                 symbol = token.symbol;
6379                 pos    = *HERE;
6380                 next_token();
6381
6382                 /* lookup entity */
6383                 entity = lookup_entity(lookup_scope, symbol, NAMESPACE_NORMAL);
6384
6385                 if (!next_if(T_COLONCOLON))
6386                         break;
6387
6388                 switch (entity->kind) {
6389                 case ENTITY_NAMESPACE:
6390                         lookup_scope = &entity->namespacee.members;
6391                         break;
6392                 case ENTITY_STRUCT:
6393                 case ENTITY_UNION:
6394                 case ENTITY_CLASS:
6395                         lookup_scope = &entity->compound.members;
6396                         break;
6397                 default:
6398                         errorf(&pos, "'%Y' must be a namespace, class, struct or union (but is a %s)",
6399                                symbol, get_entity_kind_name(entity->kind));
6400                         goto end_error;
6401                 }
6402         }
6403
6404         if (entity == NULL) {
6405                 if (!strict_mode && token.type == '(') {
6406                         /* an implicitly declared function */
6407                         if (warning.error_implicit_function_declaration) {
6408                                 errorf(&pos, "implicit declaration of function '%Y'", symbol);
6409                         } else if (warning.implicit_function_declaration) {
6410                                 warningf(&pos, "implicit declaration of function '%Y'", symbol);
6411                         }
6412
6413                         entity = create_implicit_function(symbol, &pos);
6414                 } else {
6415                         errorf(&pos, "unknown identifier '%Y' found.", symbol);
6416                         entity = create_error_entity(symbol, ENTITY_VARIABLE);
6417                 }
6418         }
6419
6420         return entity;
6421
6422 end_error:
6423         /* skip further qualifications */
6424         while (next_if(T_IDENTIFIER) && next_if(T_COLONCOLON)) {}
6425
6426         return create_error_entity(sym_anonymous, ENTITY_VARIABLE);
6427 }
6428
6429 static expression_t *parse_reference(void)
6430 {
6431         entity_t *entity = parse_qualified_identifier();
6432
6433         type_t *orig_type;
6434         if (is_declaration(entity)) {
6435                 orig_type = entity->declaration.type;
6436         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6437                 orig_type = entity->enum_value.enum_type;
6438         } else {
6439                 panic("expected declaration or enum value in reference");
6440         }
6441
6442         /* we always do the auto-type conversions; the & and sizeof parser contains
6443          * code to revert this! */
6444         type_t *type = automatic_type_conversion(orig_type);
6445
6446         expression_kind_t kind = EXPR_REFERENCE;
6447         if (entity->kind == ENTITY_ENUM_VALUE)
6448                 kind = EXPR_REFERENCE_ENUM_VALUE;
6449
6450         expression_t *expression     = allocate_expression_zero(kind);
6451         expression->reference.entity = entity;
6452         expression->base.type        = type;
6453
6454         /* this declaration is used */
6455         if (is_declaration(entity)) {
6456                 entity->declaration.used = true;
6457         }
6458
6459         if (entity->base.parent_scope != file_scope
6460                 && (current_function != NULL
6461                         && entity->base.parent_scope->depth < current_function->parameters.depth)
6462                 && (entity->kind == ENTITY_VARIABLE || entity->kind == ENTITY_PARAMETER)) {
6463                 if (entity->kind == ENTITY_VARIABLE) {
6464                         /* access of a variable from an outer function */
6465                         entity->variable.address_taken = true;
6466                 } else if (entity->kind == ENTITY_PARAMETER) {
6467                         entity->parameter.address_taken = true;
6468                 }
6469                 current_function->need_closure = true;
6470         }
6471
6472         check_deprecated(HERE, entity);
6473
6474         if (warning.init_self && entity == current_init_decl && !in_type_prop
6475             && entity->kind == ENTITY_VARIABLE) {
6476                 current_init_decl = NULL;
6477                 warningf(HERE, "variable '%#T' is initialized by itself",
6478                          entity->declaration.type, entity->base.symbol);
6479         }
6480
6481         return expression;
6482 }
6483
6484 static bool semantic_cast(expression_t *cast)
6485 {
6486         expression_t            *expression      = cast->unary.value;
6487         type_t                  *orig_dest_type  = cast->base.type;
6488         type_t                  *orig_type_right = expression->base.type;
6489         type_t            const *dst_type        = skip_typeref(orig_dest_type);
6490         type_t            const *src_type        = skip_typeref(orig_type_right);
6491         source_position_t const *pos             = &cast->base.source_position;
6492
6493         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
6494         if (dst_type == type_void)
6495                 return true;
6496
6497         /* only integer and pointer can be casted to pointer */
6498         if (is_type_pointer(dst_type)  &&
6499             !is_type_pointer(src_type) &&
6500             !is_type_integer(src_type) &&
6501             is_type_valid(src_type)) {
6502                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
6503                 return false;
6504         }
6505
6506         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
6507                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
6508                 return false;
6509         }
6510
6511         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
6512                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
6513                 return false;
6514         }
6515
6516         if (warning.cast_qual &&
6517             is_type_pointer(src_type) &&
6518             is_type_pointer(dst_type)) {
6519                 type_t *src = skip_typeref(src_type->pointer.points_to);
6520                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
6521                 unsigned missing_qualifiers =
6522                         src->base.qualifiers & ~dst->base.qualifiers;
6523                 if (missing_qualifiers != 0) {
6524                         warningf(pos,
6525                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
6526                                  missing_qualifiers, orig_type_right);
6527                 }
6528         }
6529         return true;
6530 }
6531
6532 static expression_t *parse_compound_literal(type_t *type)
6533 {
6534         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
6535
6536         parse_initializer_env_t env;
6537         env.type             = type;
6538         env.entity           = NULL;
6539         env.must_be_constant = false;
6540         initializer_t *initializer = parse_initializer(&env);
6541         type = env.type;
6542
6543         expression->compound_literal.initializer = initializer;
6544         expression->compound_literal.type        = type;
6545         expression->base.type                    = automatic_type_conversion(type);
6546
6547         return expression;
6548 }
6549
6550 /**
6551  * Parse a cast expression.
6552  */
6553 static expression_t *parse_cast(void)
6554 {
6555         add_anchor_token(')');
6556
6557         source_position_t source_position = token.source_position;
6558
6559         type_t *type = parse_typename();
6560
6561         rem_anchor_token(')');
6562         expect(')', end_error);
6563
6564         if (token.type == '{') {
6565                 return parse_compound_literal(type);
6566         }
6567
6568         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
6569         cast->base.source_position = source_position;
6570
6571         expression_t *value = parse_subexpression(PREC_CAST);
6572         cast->base.type   = type;
6573         cast->unary.value = value;
6574
6575         if (! semantic_cast(cast)) {
6576                 /* TODO: record the error in the AST. else it is impossible to detect it */
6577         }
6578
6579         return cast;
6580 end_error:
6581         return create_invalid_expression();
6582 }
6583
6584 /**
6585  * Parse a statement expression.
6586  */
6587 static expression_t *parse_statement_expression(void)
6588 {
6589         add_anchor_token(')');
6590
6591         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
6592
6593         statement_t *statement          = parse_compound_statement(true);
6594         statement->compound.stmt_expr   = true;
6595         expression->statement.statement = statement;
6596
6597         /* find last statement and use its type */
6598         type_t *type = type_void;
6599         const statement_t *stmt = statement->compound.statements;
6600         if (stmt != NULL) {
6601                 while (stmt->base.next != NULL)
6602                         stmt = stmt->base.next;
6603
6604                 if (stmt->kind == STATEMENT_EXPRESSION) {
6605                         type = stmt->expression.expression->base.type;
6606                 }
6607         } else if (warning.other) {
6608                 warningf(&expression->base.source_position, "empty statement expression ({})");
6609         }
6610         expression->base.type = type;
6611
6612         rem_anchor_token(')');
6613         expect(')', end_error);
6614
6615 end_error:
6616         return expression;
6617 }
6618
6619 /**
6620  * Parse a parenthesized expression.
6621  */
6622 static expression_t *parse_parenthesized_expression(void)
6623 {
6624         eat('(');
6625
6626         switch (token.type) {
6627         case '{':
6628                 /* gcc extension: a statement expression */
6629                 return parse_statement_expression();
6630
6631         TYPE_QUALIFIERS
6632         TYPE_SPECIFIERS
6633                 return parse_cast();
6634         case T_IDENTIFIER:
6635                 if (is_typedef_symbol(token.symbol)) {
6636                         return parse_cast();
6637                 }
6638         }
6639
6640         add_anchor_token(')');
6641         expression_t *result = parse_expression();
6642         result->base.parenthesized = true;
6643         rem_anchor_token(')');
6644         expect(')', end_error);
6645
6646 end_error:
6647         return result;
6648 }
6649
6650 static expression_t *parse_function_keyword(void)
6651 {
6652         /* TODO */
6653
6654         if (current_function == NULL) {
6655                 errorf(HERE, "'__func__' used outside of a function");
6656         }
6657
6658         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6659         expression->base.type     = type_char_ptr;
6660         expression->funcname.kind = FUNCNAME_FUNCTION;
6661
6662         next_token();
6663
6664         return expression;
6665 }
6666
6667 static expression_t *parse_pretty_function_keyword(void)
6668 {
6669         if (current_function == NULL) {
6670                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
6671         }
6672
6673         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6674         expression->base.type     = type_char_ptr;
6675         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
6676
6677         eat(T___PRETTY_FUNCTION__);
6678
6679         return expression;
6680 }
6681
6682 static expression_t *parse_funcsig_keyword(void)
6683 {
6684         if (current_function == NULL) {
6685                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
6686         }
6687
6688         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6689         expression->base.type     = type_char_ptr;
6690         expression->funcname.kind = FUNCNAME_FUNCSIG;
6691
6692         eat(T___FUNCSIG__);
6693
6694         return expression;
6695 }
6696
6697 static expression_t *parse_funcdname_keyword(void)
6698 {
6699         if (current_function == NULL) {
6700                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6701         }
6702
6703         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6704         expression->base.type     = type_char_ptr;
6705         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6706
6707         eat(T___FUNCDNAME__);
6708
6709         return expression;
6710 }
6711
6712 static designator_t *parse_designator(void)
6713 {
6714         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6715         result->source_position = *HERE;
6716
6717         if (token.type != T_IDENTIFIER) {
6718                 parse_error_expected("while parsing member designator",
6719                                      T_IDENTIFIER, NULL);
6720                 return NULL;
6721         }
6722         result->symbol = token.symbol;
6723         next_token();
6724
6725         designator_t *last_designator = result;
6726         while (true) {
6727                 if (next_if('.')) {
6728                         if (token.type != T_IDENTIFIER) {
6729                                 parse_error_expected("while parsing member designator",
6730                                                      T_IDENTIFIER, NULL);
6731                                 return NULL;
6732                         }
6733                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6734                         designator->source_position = *HERE;
6735                         designator->symbol          = token.symbol;
6736                         next_token();
6737
6738                         last_designator->next = designator;
6739                         last_designator       = designator;
6740                         continue;
6741                 }
6742                 if (next_if('[')) {
6743                         add_anchor_token(']');
6744                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6745                         designator->source_position = *HERE;
6746                         designator->array_index     = parse_expression();
6747                         rem_anchor_token(']');
6748                         expect(']', end_error);
6749                         if (designator->array_index == NULL) {
6750                                 return NULL;
6751                         }
6752
6753                         last_designator->next = designator;
6754                         last_designator       = designator;
6755                         continue;
6756                 }
6757                 break;
6758         }
6759
6760         return result;
6761 end_error:
6762         return NULL;
6763 }
6764
6765 /**
6766  * Parse the __builtin_offsetof() expression.
6767  */
6768 static expression_t *parse_offsetof(void)
6769 {
6770         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6771         expression->base.type    = type_size_t;
6772
6773         eat(T___builtin_offsetof);
6774
6775         expect('(', end_error);
6776         add_anchor_token(',');
6777         type_t *type = parse_typename();
6778         rem_anchor_token(',');
6779         expect(',', end_error);
6780         add_anchor_token(')');
6781         designator_t *designator = parse_designator();
6782         rem_anchor_token(')');
6783         expect(')', end_error);
6784
6785         expression->offsetofe.type       = type;
6786         expression->offsetofe.designator = designator;
6787
6788         type_path_t path;
6789         memset(&path, 0, sizeof(path));
6790         path.top_type = type;
6791         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6792
6793         descend_into_subtype(&path);
6794
6795         if (!walk_designator(&path, designator, true)) {
6796                 return create_invalid_expression();
6797         }
6798
6799         DEL_ARR_F(path.path);
6800
6801         return expression;
6802 end_error:
6803         return create_invalid_expression();
6804 }
6805
6806 /**
6807  * Parses a _builtin_va_start() expression.
6808  */
6809 static expression_t *parse_va_start(void)
6810 {
6811         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6812
6813         eat(T___builtin_va_start);
6814
6815         expect('(', end_error);
6816         add_anchor_token(',');
6817         expression->va_starte.ap = parse_assignment_expression();
6818         rem_anchor_token(',');
6819         expect(',', end_error);
6820         expression_t *const expr = parse_assignment_expression();
6821         if (expr->kind == EXPR_REFERENCE) {
6822                 entity_t *const entity = expr->reference.entity;
6823                 if (!current_function->base.type->function.variadic) {
6824                         errorf(&expr->base.source_position,
6825                                         "'va_start' used in non-variadic function");
6826                 } else if (entity->base.parent_scope != &current_function->parameters ||
6827                                 entity->base.next != NULL ||
6828                                 entity->kind != ENTITY_PARAMETER) {
6829                         errorf(&expr->base.source_position,
6830                                "second argument of 'va_start' must be last parameter of the current function");
6831                 } else {
6832                         expression->va_starte.parameter = &entity->variable;
6833                 }
6834                 expect(')', end_error);
6835                 return expression;
6836         }
6837         expect(')', end_error);
6838 end_error:
6839         return create_invalid_expression();
6840 }
6841
6842 /**
6843  * Parses a __builtin_va_arg() expression.
6844  */
6845 static expression_t *parse_va_arg(void)
6846 {
6847         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6848
6849         eat(T___builtin_va_arg);
6850
6851         expect('(', end_error);
6852         call_argument_t ap;
6853         ap.expression = parse_assignment_expression();
6854         expression->va_arge.ap = ap.expression;
6855         check_call_argument(type_valist, &ap, 1);
6856
6857         expect(',', end_error);
6858         expression->base.type = parse_typename();
6859         expect(')', end_error);
6860
6861         return expression;
6862 end_error:
6863         return create_invalid_expression();
6864 }
6865
6866 /**
6867  * Parses a __builtin_va_copy() expression.
6868  */
6869 static expression_t *parse_va_copy(void)
6870 {
6871         expression_t *expression = allocate_expression_zero(EXPR_VA_COPY);
6872
6873         eat(T___builtin_va_copy);
6874
6875         expect('(', end_error);
6876         expression_t *dst = parse_assignment_expression();
6877         assign_error_t error = semantic_assign(type_valist, dst);
6878         report_assign_error(error, type_valist, dst, "call argument 1",
6879                             &dst->base.source_position);
6880         expression->va_copye.dst = dst;
6881
6882         expect(',', end_error);
6883
6884         call_argument_t src;
6885         src.expression = parse_assignment_expression();
6886         check_call_argument(type_valist, &src, 2);
6887         expression->va_copye.src = src.expression;
6888         expect(')', end_error);
6889
6890         return expression;
6891 end_error:
6892         return create_invalid_expression();
6893 }
6894
6895 /**
6896  * Parses a __builtin_constant_p() expression.
6897  */
6898 static expression_t *parse_builtin_constant(void)
6899 {
6900         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6901
6902         eat(T___builtin_constant_p);
6903
6904         expect('(', end_error);
6905         add_anchor_token(')');
6906         expression->builtin_constant.value = parse_assignment_expression();
6907         rem_anchor_token(')');
6908         expect(')', end_error);
6909         expression->base.type = type_int;
6910
6911         return expression;
6912 end_error:
6913         return create_invalid_expression();
6914 }
6915
6916 /**
6917  * Parses a __builtin_types_compatible_p() expression.
6918  */
6919 static expression_t *parse_builtin_types_compatible(void)
6920 {
6921         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_TYPES_COMPATIBLE_P);
6922
6923         eat(T___builtin_types_compatible_p);
6924
6925         expect('(', end_error);
6926         add_anchor_token(')');
6927         add_anchor_token(',');
6928         expression->builtin_types_compatible.left = parse_typename();
6929         rem_anchor_token(',');
6930         expect(',', end_error);
6931         expression->builtin_types_compatible.right = parse_typename();
6932         rem_anchor_token(')');
6933         expect(')', end_error);
6934         expression->base.type = type_int;
6935
6936         return expression;
6937 end_error:
6938         return create_invalid_expression();
6939 }
6940
6941 /**
6942  * Parses a __builtin_is_*() compare expression.
6943  */
6944 static expression_t *parse_compare_builtin(void)
6945 {
6946         expression_t *expression;
6947
6948         switch (token.type) {
6949         case T___builtin_isgreater:
6950                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6951                 break;
6952         case T___builtin_isgreaterequal:
6953                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6954                 break;
6955         case T___builtin_isless:
6956                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6957                 break;
6958         case T___builtin_islessequal:
6959                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6960                 break;
6961         case T___builtin_islessgreater:
6962                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6963                 break;
6964         case T___builtin_isunordered:
6965                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6966                 break;
6967         default:
6968                 internal_errorf(HERE, "invalid compare builtin found");
6969         }
6970         expression->base.source_position = *HERE;
6971         next_token();
6972
6973         expect('(', end_error);
6974         expression->binary.left = parse_assignment_expression();
6975         expect(',', end_error);
6976         expression->binary.right = parse_assignment_expression();
6977         expect(')', end_error);
6978
6979         type_t *const orig_type_left  = expression->binary.left->base.type;
6980         type_t *const orig_type_right = expression->binary.right->base.type;
6981
6982         type_t *const type_left  = skip_typeref(orig_type_left);
6983         type_t *const type_right = skip_typeref(orig_type_right);
6984         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6985                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6986                         type_error_incompatible("invalid operands in comparison",
6987                                 &expression->base.source_position, orig_type_left, orig_type_right);
6988                 }
6989         } else {
6990                 semantic_comparison(&expression->binary);
6991         }
6992
6993         return expression;
6994 end_error:
6995         return create_invalid_expression();
6996 }
6997
6998 /**
6999  * Parses a MS assume() expression.
7000  */
7001 static expression_t *parse_assume(void)
7002 {
7003         expression_t *expression = allocate_expression_zero(EXPR_UNARY_ASSUME);
7004
7005         eat(T__assume);
7006
7007         expect('(', end_error);
7008         add_anchor_token(')');
7009         expression->unary.value = parse_assignment_expression();
7010         rem_anchor_token(')');
7011         expect(')', end_error);
7012
7013         expression->base.type = type_void;
7014         return expression;
7015 end_error:
7016         return create_invalid_expression();
7017 }
7018
7019 /**
7020  * Return the declaration for a given label symbol or create a new one.
7021  *
7022  * @param symbol  the symbol of the label
7023  */
7024 static label_t *get_label(symbol_t *symbol)
7025 {
7026         entity_t *label;
7027         assert(current_function != NULL);
7028
7029         label = get_entity(symbol, NAMESPACE_LABEL);
7030         /* if we found a local label, we already created the declaration */
7031         if (label != NULL && label->kind == ENTITY_LOCAL_LABEL) {
7032                 if (label->base.parent_scope != current_scope) {
7033                         assert(label->base.parent_scope->depth < current_scope->depth);
7034                         current_function->goto_to_outer = true;
7035                 }
7036                 return &label->label;
7037         }
7038
7039         label = get_entity(symbol, NAMESPACE_LABEL);
7040         /* if we found a label in the same function, then we already created the
7041          * declaration */
7042         if (label != NULL
7043                         && label->base.parent_scope == &current_function->parameters) {
7044                 return &label->label;
7045         }
7046
7047         /* otherwise we need to create a new one */
7048         label               = allocate_entity_zero(ENTITY_LABEL);
7049         label->base.namespc = NAMESPACE_LABEL;
7050         label->base.symbol  = symbol;
7051
7052         label_push(label);
7053
7054         return &label->label;
7055 }
7056
7057 /**
7058  * Parses a GNU && label address expression.
7059  */
7060 static expression_t *parse_label_address(void)
7061 {
7062         source_position_t source_position = token.source_position;
7063         eat(T_ANDAND);
7064         if (token.type != T_IDENTIFIER) {
7065                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7066                 goto end_error;
7067         }
7068         symbol_t *symbol = token.symbol;
7069         next_token();
7070
7071         label_t *label       = get_label(symbol);
7072         label->used          = true;
7073         label->address_taken = true;
7074
7075         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7076         expression->base.source_position = source_position;
7077
7078         /* label address is threaten as a void pointer */
7079         expression->base.type           = type_void_ptr;
7080         expression->label_address.label = label;
7081         return expression;
7082 end_error:
7083         return create_invalid_expression();
7084 }
7085
7086 /**
7087  * Parse a microsoft __noop expression.
7088  */
7089 static expression_t *parse_noop_expression(void)
7090 {
7091         /* the result is a (int)0 */
7092         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_MS_NOOP);
7093         literal->base.type            = type_int;
7094         literal->base.source_position = token.source_position;
7095         literal->literal.value.begin  = "__noop";
7096         literal->literal.value.size   = 6;
7097
7098         eat(T___noop);
7099
7100         if (token.type == '(') {
7101                 /* parse arguments */
7102                 eat('(');
7103                 add_anchor_token(')');
7104                 add_anchor_token(',');
7105
7106                 if (token.type != ')') do {
7107                         (void)parse_assignment_expression();
7108                 } while (next_if(','));
7109         }
7110         rem_anchor_token(',');
7111         rem_anchor_token(')');
7112         expect(')', end_error);
7113
7114 end_error:
7115         return literal;
7116 }
7117
7118 /**
7119  * Parses a primary expression.
7120  */
7121 static expression_t *parse_primary_expression(void)
7122 {
7123         switch (token.type) {
7124         case T_false:                        return parse_boolean_literal(false);
7125         case T_true:                         return parse_boolean_literal(true);
7126         case T_INTEGER:
7127         case T_INTEGER_OCTAL:
7128         case T_INTEGER_HEXADECIMAL:
7129         case T_FLOATINGPOINT:
7130         case T_FLOATINGPOINT_HEXADECIMAL:    return parse_number_literal();
7131         case T_CHARACTER_CONSTANT:           return parse_character_constant();
7132         case T_WIDE_CHARACTER_CONSTANT:      return parse_wide_character_constant();
7133         case T_STRING_LITERAL:
7134         case T_WIDE_STRING_LITERAL:          return parse_string_literal();
7135         case T___FUNCTION__:
7136         case T___func__:                     return parse_function_keyword();
7137         case T___PRETTY_FUNCTION__:          return parse_pretty_function_keyword();
7138         case T___FUNCSIG__:                  return parse_funcsig_keyword();
7139         case T___FUNCDNAME__:                return parse_funcdname_keyword();
7140         case T___builtin_offsetof:           return parse_offsetof();
7141         case T___builtin_va_start:           return parse_va_start();
7142         case T___builtin_va_arg:             return parse_va_arg();
7143         case T___builtin_va_copy:            return parse_va_copy();
7144         case T___builtin_isgreater:
7145         case T___builtin_isgreaterequal:
7146         case T___builtin_isless:
7147         case T___builtin_islessequal:
7148         case T___builtin_islessgreater:
7149         case T___builtin_isunordered:        return parse_compare_builtin();
7150         case T___builtin_constant_p:         return parse_builtin_constant();
7151         case T___builtin_types_compatible_p: return parse_builtin_types_compatible();
7152         case T__assume:                      return parse_assume();
7153         case T_ANDAND:
7154                 if (GNU_MODE)
7155                         return parse_label_address();
7156                 break;
7157
7158         case '(':                            return parse_parenthesized_expression();
7159         case T___noop:                       return parse_noop_expression();
7160
7161         /* Gracefully handle type names while parsing expressions. */
7162         case T_COLONCOLON:
7163                 return parse_reference();
7164         case T_IDENTIFIER:
7165                 if (!is_typedef_symbol(token.symbol)) {
7166                         return parse_reference();
7167                 }
7168                 /* FALLTHROUGH */
7169         TYPENAME_START {
7170                 source_position_t  const pos  = *HERE;
7171                 type_t const      *const type = parse_typename();
7172                 errorf(&pos, "encountered type '%T' while parsing expression", type);
7173                 return create_invalid_expression();
7174         }
7175         }
7176
7177         errorf(HERE, "unexpected token %K, expected an expression", &token);
7178         eat_until_anchor();
7179         return create_invalid_expression();
7180 }
7181
7182 /**
7183  * Check if the expression has the character type and issue a warning then.
7184  */
7185 static void check_for_char_index_type(const expression_t *expression)
7186 {
7187         type_t       *const type      = expression->base.type;
7188         const type_t *const base_type = skip_typeref(type);
7189
7190         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7191                         warning.char_subscripts) {
7192                 warningf(&expression->base.source_position,
7193                          "array subscript has type '%T'", type);
7194         }
7195 }
7196
7197 static expression_t *parse_array_expression(expression_t *left)
7198 {
7199         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7200
7201         eat('[');
7202         add_anchor_token(']');
7203
7204         expression_t *inside = parse_expression();
7205
7206         type_t *const orig_type_left   = left->base.type;
7207         type_t *const orig_type_inside = inside->base.type;
7208
7209         type_t *const type_left   = skip_typeref(orig_type_left);
7210         type_t *const type_inside = skip_typeref(orig_type_inside);
7211
7212         type_t                    *return_type;
7213         array_access_expression_t *array_access = &expression->array_access;
7214         if (is_type_pointer(type_left)) {
7215                 return_type             = type_left->pointer.points_to;
7216                 array_access->array_ref = left;
7217                 array_access->index     = inside;
7218                 check_for_char_index_type(inside);
7219         } else if (is_type_pointer(type_inside)) {
7220                 return_type             = type_inside->pointer.points_to;
7221                 array_access->array_ref = inside;
7222                 array_access->index     = left;
7223                 array_access->flipped   = true;
7224                 check_for_char_index_type(left);
7225         } else {
7226                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7227                         errorf(HERE,
7228                                 "array access on object with non-pointer types '%T', '%T'",
7229                                 orig_type_left, orig_type_inside);
7230                 }
7231                 return_type             = type_error_type;
7232                 array_access->array_ref = left;
7233                 array_access->index     = inside;
7234         }
7235
7236         expression->base.type = automatic_type_conversion(return_type);
7237
7238         rem_anchor_token(']');
7239         expect(']', end_error);
7240 end_error:
7241         return expression;
7242 }
7243
7244 static expression_t *parse_typeprop(expression_kind_t const kind)
7245 {
7246         expression_t  *tp_expression = allocate_expression_zero(kind);
7247         tp_expression->base.type     = type_size_t;
7248
7249         eat(kind == EXPR_SIZEOF ? T_sizeof : T___alignof__);
7250
7251         /* we only refer to a type property, mark this case */
7252         bool old     = in_type_prop;
7253         in_type_prop = true;
7254
7255         type_t       *orig_type;
7256         expression_t *expression;
7257         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7258                 next_token();
7259                 add_anchor_token(')');
7260                 orig_type = parse_typename();
7261                 rem_anchor_token(')');
7262                 expect(')', end_error);
7263
7264                 if (token.type == '{') {
7265                         /* It was not sizeof(type) after all.  It is sizeof of an expression
7266                          * starting with a compound literal */
7267                         expression = parse_compound_literal(orig_type);
7268                         goto typeprop_expression;
7269                 }
7270         } else {
7271                 expression = parse_subexpression(PREC_UNARY);
7272
7273 typeprop_expression:
7274                 tp_expression->typeprop.tp_expression = expression;
7275
7276                 orig_type = revert_automatic_type_conversion(expression);
7277                 expression->base.type = orig_type;
7278         }
7279
7280         tp_expression->typeprop.type   = orig_type;
7281         type_t const* const type       = skip_typeref(orig_type);
7282         char   const*       wrong_type = NULL;
7283         if (is_type_incomplete(type)) {
7284                 if (!is_type_atomic(type, ATOMIC_TYPE_VOID) || !GNU_MODE)
7285                         wrong_type = "incomplete";
7286         } else if (type->kind == TYPE_FUNCTION) {
7287                 if (GNU_MODE) {
7288                         /* function types are allowed (and return 1) */
7289                         if (warning.other) {
7290                                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7291                                 warningf(&tp_expression->base.source_position,
7292                                          "%s expression with function argument returns invalid result", what);
7293                         }
7294                 } else {
7295                         wrong_type = "function";
7296                 }
7297         } else {
7298                 if (is_type_incomplete(type))
7299                         wrong_type = "incomplete";
7300         }
7301         if (type->kind == TYPE_BITFIELD)
7302                 wrong_type = "bitfield";
7303
7304         if (wrong_type != NULL) {
7305                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7306                 errorf(&tp_expression->base.source_position,
7307                                 "operand of %s expression must not be of %s type '%T'",
7308                                 what, wrong_type, orig_type);
7309         }
7310
7311 end_error:
7312         in_type_prop = old;
7313         return tp_expression;
7314 }
7315
7316 static expression_t *parse_sizeof(void)
7317 {
7318         return parse_typeprop(EXPR_SIZEOF);
7319 }
7320
7321 static expression_t *parse_alignof(void)
7322 {
7323         return parse_typeprop(EXPR_ALIGNOF);
7324 }
7325
7326 static expression_t *parse_select_expression(expression_t *addr)
7327 {
7328         assert(token.type == '.' || token.type == T_MINUSGREATER);
7329         bool select_left_arrow = (token.type == T_MINUSGREATER);
7330         source_position_t const pos = *HERE;
7331         next_token();
7332
7333         if (token.type != T_IDENTIFIER) {
7334                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7335                 return create_invalid_expression();
7336         }
7337         symbol_t *symbol = token.symbol;
7338         next_token();
7339
7340         type_t *const orig_type = addr->base.type;
7341         type_t *const type      = skip_typeref(orig_type);
7342
7343         type_t *type_left;
7344         bool    saw_error = false;
7345         if (is_type_pointer(type)) {
7346                 if (!select_left_arrow) {
7347                         errorf(&pos,
7348                                "request for member '%Y' in something not a struct or union, but '%T'",
7349                                symbol, orig_type);
7350                         saw_error = true;
7351                 }
7352                 type_left = skip_typeref(type->pointer.points_to);
7353         } else {
7354                 if (select_left_arrow && is_type_valid(type)) {
7355                         errorf(&pos, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7356                         saw_error = true;
7357                 }
7358                 type_left = type;
7359         }
7360
7361         if (type_left->kind != TYPE_COMPOUND_STRUCT &&
7362             type_left->kind != TYPE_COMPOUND_UNION) {
7363
7364                 if (is_type_valid(type_left) && !saw_error) {
7365                         errorf(&pos,
7366                                "request for member '%Y' in something not a struct or union, but '%T'",
7367                                symbol, type_left);
7368                 }
7369                 return create_invalid_expression();
7370         }
7371
7372         compound_t *compound = type_left->compound.compound;
7373         if (!compound->complete) {
7374                 errorf(&pos, "request for member '%Y' in incomplete type '%T'",
7375                        symbol, type_left);
7376                 return create_invalid_expression();
7377         }
7378
7379         type_qualifiers_t  qualifiers = type_left->base.qualifiers;
7380         expression_t      *result     =
7381                 find_create_select(&pos, addr, qualifiers, compound, symbol);
7382
7383         if (result == NULL) {
7384                 errorf(&pos, "'%T' has no member named '%Y'", orig_type, symbol);
7385                 return create_invalid_expression();
7386         }
7387
7388         return result;
7389 }
7390
7391 static void check_call_argument(type_t          *expected_type,
7392                                 call_argument_t *argument, unsigned pos)
7393 {
7394         type_t         *expected_type_skip = skip_typeref(expected_type);
7395         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7396         expression_t   *arg_expr           = argument->expression;
7397         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7398
7399         /* handle transparent union gnu extension */
7400         if (is_type_union(expected_type_skip)
7401                         && (get_type_modifiers(expected_type) & DM_TRANSPARENT_UNION)) {
7402                 compound_t *union_decl  = expected_type_skip->compound.compound;
7403                 type_t     *best_type   = NULL;
7404                 entity_t   *entry       = union_decl->members.entities;
7405                 for ( ; entry != NULL; entry = entry->base.next) {
7406                         assert(is_declaration(entry));
7407                         type_t *decl_type = entry->declaration.type;
7408                         error = semantic_assign(decl_type, arg_expr);
7409                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7410                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
7411                                 continue;
7412
7413                         if (error == ASSIGN_SUCCESS) {
7414                                 best_type = decl_type;
7415                         } else if (best_type == NULL) {
7416                                 best_type = decl_type;
7417                         }
7418                 }
7419
7420                 if (best_type != NULL) {
7421                         expected_type = best_type;
7422                 }
7423         }
7424
7425         error                = semantic_assign(expected_type, arg_expr);
7426         argument->expression = create_implicit_cast(arg_expr, expected_type);
7427
7428         if (error != ASSIGN_SUCCESS) {
7429                 /* report exact scope in error messages (like "in argument 3") */
7430                 char buf[64];
7431                 snprintf(buf, sizeof(buf), "call argument %u", pos);
7432                 report_assign_error(error, expected_type, arg_expr, buf,
7433                                     &arg_expr->base.source_position);
7434         } else if (warning.traditional || warning.conversion) {
7435                 type_t *const promoted_type = get_default_promoted_type(arg_type);
7436                 if (!types_compatible(expected_type_skip, promoted_type) &&
7437                     !types_compatible(expected_type_skip, type_void_ptr) &&
7438                     !types_compatible(type_void_ptr,      promoted_type)) {
7439                         /* Deliberately show the skipped types in this warning */
7440                         warningf(&arg_expr->base.source_position,
7441                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
7442                                 pos, expected_type_skip, promoted_type);
7443                 }
7444         }
7445 }
7446
7447 /**
7448  * Handle the semantic restrictions of builtin calls
7449  */
7450 static void handle_builtin_argument_restrictions(call_expression_t *call) {
7451         switch (call->function->reference.entity->function.btk) {
7452                 case bk_gnu_builtin_return_address:
7453                 case bk_gnu_builtin_frame_address: {
7454                         /* argument must be constant */
7455                         call_argument_t *argument = call->arguments;
7456
7457                         if (is_constant_expression(argument->expression) == EXPR_CLASS_VARIABLE) {
7458                                 errorf(&call->base.source_position,
7459                                        "argument of '%Y' must be a constant expression",
7460                                        call->function->reference.entity->base.symbol);
7461                         }
7462                         break;
7463                 }
7464                 case bk_gnu_builtin_object_size:
7465                         if (call->arguments == NULL)
7466                                 break;
7467
7468                         call_argument_t *arg = call->arguments->next;
7469                         if (arg != NULL && is_constant_expression(arg->expression) == EXPR_CLASS_VARIABLE) {
7470                                 errorf(&call->base.source_position,
7471                                            "second argument of '%Y' must be a constant expression",
7472                                            call->function->reference.entity->base.symbol);
7473                         }
7474                         break;
7475                 case bk_gnu_builtin_prefetch:
7476                         /* second and third argument must be constant if existent */
7477                         if (call->arguments == NULL)
7478                                 break;
7479                         call_argument_t *rw = call->arguments->next;
7480                         call_argument_t *locality = NULL;
7481
7482                         if (rw != NULL) {
7483                                 if (is_constant_expression(rw->expression) == EXPR_CLASS_VARIABLE) {
7484                                         errorf(&call->base.source_position,
7485                                                "second argument of '%Y' must be a constant expression",
7486                                                call->function->reference.entity->base.symbol);
7487                                 }
7488                                 locality = rw->next;
7489                         }
7490                         if (locality != NULL) {
7491                                 if (is_constant_expression(locality->expression) == EXPR_CLASS_VARIABLE) {
7492                                         errorf(&call->base.source_position,
7493                                                "third argument of '%Y' must be a constant expression",
7494                                                call->function->reference.entity->base.symbol);
7495                                 }
7496                                 locality = rw->next;
7497                         }
7498                         break;
7499                 default:
7500                         break;
7501         }
7502 }
7503
7504 /**
7505  * Parse a call expression, ie. expression '( ... )'.
7506  *
7507  * @param expression  the function address
7508  */
7509 static expression_t *parse_call_expression(expression_t *expression)
7510 {
7511         expression_t      *result = allocate_expression_zero(EXPR_CALL);
7512         call_expression_t *call   = &result->call;
7513         call->function            = expression;
7514
7515         type_t *const orig_type = expression->base.type;
7516         type_t *const type      = skip_typeref(orig_type);
7517
7518         function_type_t *function_type = NULL;
7519         if (is_type_pointer(type)) {
7520                 type_t *const to_type = skip_typeref(type->pointer.points_to);
7521
7522                 if (is_type_function(to_type)) {
7523                         function_type   = &to_type->function;
7524                         call->base.type = function_type->return_type;
7525                 }
7526         }
7527
7528         if (function_type == NULL && is_type_valid(type)) {
7529                 errorf(HERE,
7530                        "called object '%E' (type '%T') is not a pointer to a function",
7531                        expression, orig_type);
7532         }
7533
7534         /* parse arguments */
7535         eat('(');
7536         add_anchor_token(')');
7537         add_anchor_token(',');
7538
7539         if (token.type != ')') {
7540                 call_argument_t **anchor = &call->arguments;
7541                 do {
7542                         call_argument_t *argument = allocate_ast_zero(sizeof(*argument));
7543                         argument->expression = parse_assignment_expression();
7544
7545                         *anchor = argument;
7546                         anchor  = &argument->next;
7547                 } while (next_if(','));
7548         }
7549         rem_anchor_token(',');
7550         rem_anchor_token(')');
7551         expect(')', end_error);
7552
7553         if (function_type == NULL)
7554                 return result;
7555
7556         /* check type and count of call arguments */
7557         function_parameter_t *parameter = function_type->parameters;
7558         call_argument_t      *argument  = call->arguments;
7559         if (!function_type->unspecified_parameters) {
7560                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
7561                                 parameter = parameter->next, argument = argument->next) {
7562                         check_call_argument(parameter->type, argument, ++pos);
7563                 }
7564
7565                 if (parameter != NULL) {
7566                         errorf(HERE, "too few arguments to function '%E'", expression);
7567                 } else if (argument != NULL && !function_type->variadic) {
7568                         errorf(HERE, "too many arguments to function '%E'", expression);
7569                 }
7570         }
7571
7572         /* do default promotion for other arguments */
7573         for (; argument != NULL; argument = argument->next) {
7574                 type_t *type = argument->expression->base.type;
7575                 if (!is_type_object(skip_typeref(type))) {
7576                         errorf(&argument->expression->base.source_position,
7577                                "call argument '%E' must not be void", argument->expression);
7578                 }
7579
7580                 type = get_default_promoted_type(type);
7581
7582                 argument->expression
7583                         = create_implicit_cast(argument->expression, type);
7584         }
7585
7586         check_format(&result->call);
7587
7588         if (warning.aggregate_return &&
7589             is_type_compound(skip_typeref(function_type->return_type))) {
7590                 warningf(&result->base.source_position,
7591                          "function call has aggregate value");
7592         }
7593
7594         if (call->function->kind == EXPR_REFERENCE) {
7595                 reference_expression_t *reference = &call->function->reference;
7596                 if (reference->entity->kind == ENTITY_FUNCTION &&
7597                     reference->entity->function.btk != bk_none)
7598                         handle_builtin_argument_restrictions(call);
7599         }
7600
7601 end_error:
7602         return result;
7603 }
7604
7605 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
7606
7607 static bool same_compound_type(const type_t *type1, const type_t *type2)
7608 {
7609         return
7610                 is_type_compound(type1) &&
7611                 type1->kind == type2->kind &&
7612                 type1->compound.compound == type2->compound.compound;
7613 }
7614
7615 static expression_t const *get_reference_address(expression_t const *expr)
7616 {
7617         bool regular_take_address = true;
7618         for (;;) {
7619                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
7620                         expr = expr->unary.value;
7621                 } else {
7622                         regular_take_address = false;
7623                 }
7624
7625                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
7626                         break;
7627
7628                 expr = expr->unary.value;
7629         }
7630
7631         if (expr->kind != EXPR_REFERENCE)
7632                 return NULL;
7633
7634         /* special case for functions which are automatically converted to a
7635          * pointer to function without an extra TAKE_ADDRESS operation */
7636         if (!regular_take_address &&
7637                         expr->reference.entity->kind != ENTITY_FUNCTION) {
7638                 return NULL;
7639         }
7640
7641         return expr;
7642 }
7643
7644 static void warn_reference_address_as_bool(expression_t const* expr)
7645 {
7646         if (!warning.address)
7647                 return;
7648
7649         expr = get_reference_address(expr);
7650         if (expr != NULL) {
7651                 warningf(&expr->base.source_position,
7652                          "the address of '%Y' will always evaluate as 'true'",
7653                          expr->reference.entity->base.symbol);
7654         }
7655 }
7656
7657 static void warn_assignment_in_condition(const expression_t *const expr)
7658 {
7659         if (!warning.parentheses)
7660                 return;
7661         if (expr->base.kind != EXPR_BINARY_ASSIGN)
7662                 return;
7663         if (expr->base.parenthesized)
7664                 return;
7665         warningf(&expr->base.source_position,
7666                         "suggest parentheses around assignment used as truth value");
7667 }
7668
7669 static void semantic_condition(expression_t const *const expr,
7670                                char const *const context)
7671 {
7672         type_t *const type = skip_typeref(expr->base.type);
7673         if (is_type_scalar(type)) {
7674                 warn_reference_address_as_bool(expr);
7675                 warn_assignment_in_condition(expr);
7676         } else if (is_type_valid(type)) {
7677                 errorf(&expr->base.source_position,
7678                                 "%s must have scalar type", context);
7679         }
7680 }
7681
7682 /**
7683  * Parse a conditional expression, ie. 'expression ? ... : ...'.
7684  *
7685  * @param expression  the conditional expression
7686  */
7687 static expression_t *parse_conditional_expression(expression_t *expression)
7688 {
7689         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
7690
7691         conditional_expression_t *conditional = &result->conditional;
7692         conditional->condition                = expression;
7693
7694         eat('?');
7695         add_anchor_token(':');
7696
7697         /* §6.5.15:2  The first operand shall have scalar type. */
7698         semantic_condition(expression, "condition of conditional operator");
7699
7700         expression_t *true_expression = expression;
7701         bool          gnu_cond = false;
7702         if (GNU_MODE && token.type == ':') {
7703                 gnu_cond = true;
7704         } else {
7705                 true_expression = parse_expression();
7706         }
7707         rem_anchor_token(':');
7708         expect(':', end_error);
7709 end_error:;
7710         expression_t *false_expression =
7711                 parse_subexpression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
7712
7713         type_t *const orig_true_type  = true_expression->base.type;
7714         type_t *const orig_false_type = false_expression->base.type;
7715         type_t *const true_type       = skip_typeref(orig_true_type);
7716         type_t *const false_type      = skip_typeref(orig_false_type);
7717
7718         /* 6.5.15.3 */
7719         type_t *result_type;
7720         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
7721                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7722                 /* ISO/IEC 14882:1998(E) §5.16:2 */
7723                 if (true_expression->kind == EXPR_UNARY_THROW) {
7724                         result_type = false_type;
7725                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
7726                         result_type = true_type;
7727                 } else {
7728                         if (warning.other && (
7729                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
7730                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
7731                                         )) {
7732                                 warningf(&conditional->base.source_position,
7733                                                 "ISO C forbids conditional expression with only one void side");
7734                         }
7735                         result_type = type_void;
7736                 }
7737         } else if (is_type_arithmetic(true_type)
7738                    && is_type_arithmetic(false_type)) {
7739                 result_type = semantic_arithmetic(true_type, false_type);
7740         } else if (same_compound_type(true_type, false_type)) {
7741                 /* just take 1 of the 2 types */
7742                 result_type = true_type;
7743         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
7744                 type_t *pointer_type;
7745                 type_t *other_type;
7746                 expression_t *other_expression;
7747                 if (is_type_pointer(true_type) &&
7748                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
7749                         pointer_type     = true_type;
7750                         other_type       = false_type;
7751                         other_expression = false_expression;
7752                 } else {
7753                         pointer_type     = false_type;
7754                         other_type       = true_type;
7755                         other_expression = true_expression;
7756                 }
7757
7758                 if (is_null_pointer_constant(other_expression)) {
7759                         result_type = pointer_type;
7760                 } else if (is_type_pointer(other_type)) {
7761                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
7762                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
7763
7764                         type_t *to;
7765                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
7766                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
7767                                 to = type_void;
7768                         } else if (types_compatible(get_unqualified_type(to1),
7769                                                     get_unqualified_type(to2))) {
7770                                 to = to1;
7771                         } else {
7772                                 if (warning.other) {
7773                                         warningf(&conditional->base.source_position,
7774                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
7775                                                         true_type, false_type);
7776                                 }
7777                                 to = type_void;
7778                         }
7779
7780                         type_t *const type =
7781                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
7782                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
7783                 } else if (is_type_integer(other_type)) {
7784                         if (warning.other) {
7785                                 warningf(&conditional->base.source_position,
7786                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
7787                         }
7788                         result_type = pointer_type;
7789                 } else {
7790                         if (is_type_valid(other_type)) {
7791                                 type_error_incompatible("while parsing conditional",
7792                                                 &expression->base.source_position, true_type, false_type);
7793                         }
7794                         result_type = type_error_type;
7795                 }
7796         } else {
7797                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
7798                         type_error_incompatible("while parsing conditional",
7799                                                 &conditional->base.source_position, true_type,
7800                                                 false_type);
7801                 }
7802                 result_type = type_error_type;
7803         }
7804
7805         conditional->true_expression
7806                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
7807         conditional->false_expression
7808                 = create_implicit_cast(false_expression, result_type);
7809         conditional->base.type = result_type;
7810         return result;
7811 }
7812
7813 /**
7814  * Parse an extension expression.
7815  */
7816 static expression_t *parse_extension(void)
7817 {
7818         eat(T___extension__);
7819
7820         bool old_gcc_extension   = in_gcc_extension;
7821         in_gcc_extension         = true;
7822         expression_t *expression = parse_subexpression(PREC_UNARY);
7823         in_gcc_extension         = old_gcc_extension;
7824         return expression;
7825 }
7826
7827 /**
7828  * Parse a __builtin_classify_type() expression.
7829  */
7830 static expression_t *parse_builtin_classify_type(void)
7831 {
7832         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
7833         result->base.type    = type_int;
7834
7835         eat(T___builtin_classify_type);
7836
7837         expect('(', end_error);
7838         add_anchor_token(')');
7839         expression_t *expression = parse_expression();
7840         rem_anchor_token(')');
7841         expect(')', end_error);
7842         result->classify_type.type_expression = expression;
7843
7844         return result;
7845 end_error:
7846         return create_invalid_expression();
7847 }
7848
7849 /**
7850  * Parse a delete expression
7851  * ISO/IEC 14882:1998(E) §5.3.5
7852  */
7853 static expression_t *parse_delete(void)
7854 {
7855         expression_t *const result = allocate_expression_zero(EXPR_UNARY_DELETE);
7856         result->base.type          = type_void;
7857
7858         eat(T_delete);
7859
7860         if (next_if('[')) {
7861                 result->kind = EXPR_UNARY_DELETE_ARRAY;
7862                 expect(']', end_error);
7863 end_error:;
7864         }
7865
7866         expression_t *const value = parse_subexpression(PREC_CAST);
7867         result->unary.value = value;
7868
7869         type_t *const type = skip_typeref(value->base.type);
7870         if (!is_type_pointer(type)) {
7871                 if (is_type_valid(type)) {
7872                         errorf(&value->base.source_position,
7873                                         "operand of delete must have pointer type");
7874                 }
7875         } else if (warning.other &&
7876                         is_type_atomic(skip_typeref(type->pointer.points_to), ATOMIC_TYPE_VOID)) {
7877                 warningf(&value->base.source_position,
7878                                 "deleting 'void*' is undefined");
7879         }
7880
7881         return result;
7882 }
7883
7884 /**
7885  * Parse a throw expression
7886  * ISO/IEC 14882:1998(E) §15:1
7887  */
7888 static expression_t *parse_throw(void)
7889 {
7890         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
7891         result->base.type          = type_void;
7892
7893         eat(T_throw);
7894
7895         expression_t *value = NULL;
7896         switch (token.type) {
7897                 EXPRESSION_START {
7898                         value = parse_assignment_expression();
7899                         /* ISO/IEC 14882:1998(E) §15.1:3 */
7900                         type_t *const orig_type = value->base.type;
7901                         type_t *const type      = skip_typeref(orig_type);
7902                         if (is_type_incomplete(type)) {
7903                                 errorf(&value->base.source_position,
7904                                                 "cannot throw object of incomplete type '%T'", orig_type);
7905                         } else if (is_type_pointer(type)) {
7906                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
7907                                 if (is_type_incomplete(points_to) &&
7908                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7909                                         errorf(&value->base.source_position,
7910                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
7911                                 }
7912                         }
7913                 }
7914
7915                 default:
7916                         break;
7917         }
7918         result->unary.value = value;
7919
7920         return result;
7921 }
7922
7923 static bool check_pointer_arithmetic(const source_position_t *source_position,
7924                                      type_t *pointer_type,
7925                                      type_t *orig_pointer_type)
7926 {
7927         type_t *points_to = pointer_type->pointer.points_to;
7928         points_to = skip_typeref(points_to);
7929
7930         if (is_type_incomplete(points_to)) {
7931                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7932                         errorf(source_position,
7933                                "arithmetic with pointer to incomplete type '%T' not allowed",
7934                                orig_pointer_type);
7935                         return false;
7936                 } else if (warning.pointer_arith) {
7937                         warningf(source_position,
7938                                  "pointer of type '%T' used in arithmetic",
7939                                  orig_pointer_type);
7940                 }
7941         } else if (is_type_function(points_to)) {
7942                 if (!GNU_MODE) {
7943                         errorf(source_position,
7944                                "arithmetic with pointer to function type '%T' not allowed",
7945                                orig_pointer_type);
7946                         return false;
7947                 } else if (warning.pointer_arith) {
7948                         warningf(source_position,
7949                                  "pointer to a function '%T' used in arithmetic",
7950                                  orig_pointer_type);
7951                 }
7952         }
7953         return true;
7954 }
7955
7956 static bool is_lvalue(const expression_t *expression)
7957 {
7958         /* TODO: doesn't seem to be consistent with §6.3.2.1:1 */
7959         switch (expression->kind) {
7960         case EXPR_ARRAY_ACCESS:
7961         case EXPR_COMPOUND_LITERAL:
7962         case EXPR_REFERENCE:
7963         case EXPR_SELECT:
7964         case EXPR_UNARY_DEREFERENCE:
7965                 return true;
7966
7967         default: {
7968                 type_t *type = skip_typeref(expression->base.type);
7969                 return
7970                         /* ISO/IEC 14882:1998(E) §3.10:3 */
7971                         is_type_reference(type) ||
7972                         /* Claim it is an lvalue, if the type is invalid.  There was a parse
7973                          * error before, which maybe prevented properly recognizing it as
7974                          * lvalue. */
7975                         !is_type_valid(type);
7976         }
7977         }
7978 }
7979
7980 static void semantic_incdec(unary_expression_t *expression)
7981 {
7982         type_t *const orig_type = expression->value->base.type;
7983         type_t *const type      = skip_typeref(orig_type);
7984         if (is_type_pointer(type)) {
7985                 if (!check_pointer_arithmetic(&expression->base.source_position,
7986                                               type, orig_type)) {
7987                         return;
7988                 }
7989         } else if (!is_type_real(type) && is_type_valid(type)) {
7990                 /* TODO: improve error message */
7991                 errorf(&expression->base.source_position,
7992                        "operation needs an arithmetic or pointer type");
7993                 return;
7994         }
7995         if (!is_lvalue(expression->value)) {
7996                 /* TODO: improve error message */
7997                 errorf(&expression->base.source_position, "lvalue required as operand");
7998         }
7999         expression->base.type = orig_type;
8000 }
8001
8002 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
8003 {
8004         type_t *const orig_type = expression->value->base.type;
8005         type_t *const type      = skip_typeref(orig_type);
8006         if (!is_type_arithmetic(type)) {
8007                 if (is_type_valid(type)) {
8008                         /* TODO: improve error message */
8009                         errorf(&expression->base.source_position,
8010                                 "operation needs an arithmetic type");
8011                 }
8012                 return;
8013         }
8014
8015         expression->base.type = orig_type;
8016 }
8017
8018 static void semantic_unexpr_plus(unary_expression_t *expression)
8019 {
8020         semantic_unexpr_arithmetic(expression);
8021         if (warning.traditional)
8022                 warningf(&expression->base.source_position,
8023                         "traditional C rejects the unary plus operator");
8024 }
8025
8026 static void semantic_not(unary_expression_t *expression)
8027 {
8028         /* §6.5.3.3:1  The operand [...] of the ! operator, scalar type. */
8029         semantic_condition(expression->value, "operand of !");
8030         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8031 }
8032
8033 static void semantic_unexpr_integer(unary_expression_t *expression)
8034 {
8035         type_t *const orig_type = expression->value->base.type;
8036         type_t *const type      = skip_typeref(orig_type);
8037         if (!is_type_integer(type)) {
8038                 if (is_type_valid(type)) {
8039                         errorf(&expression->base.source_position,
8040                                "operand of ~ must be of integer type");
8041                 }
8042                 return;
8043         }
8044
8045         expression->base.type = orig_type;
8046 }
8047
8048 static void semantic_dereference(unary_expression_t *expression)
8049 {
8050         type_t *const orig_type = expression->value->base.type;
8051         type_t *const type      = skip_typeref(orig_type);
8052         if (!is_type_pointer(type)) {
8053                 if (is_type_valid(type)) {
8054                         errorf(&expression->base.source_position,
8055                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
8056                 }
8057                 return;
8058         }
8059
8060         type_t *result_type   = type->pointer.points_to;
8061         result_type           = automatic_type_conversion(result_type);
8062         expression->base.type = result_type;
8063 }
8064
8065 /**
8066  * Record that an address is taken (expression represents an lvalue).
8067  *
8068  * @param expression       the expression
8069  * @param may_be_register  if true, the expression might be an register
8070  */
8071 static void set_address_taken(expression_t *expression, bool may_be_register)
8072 {
8073         if (expression->kind != EXPR_REFERENCE)
8074                 return;
8075
8076         entity_t *const entity = expression->reference.entity;
8077
8078         if (entity->kind != ENTITY_VARIABLE && entity->kind != ENTITY_PARAMETER)
8079                 return;
8080
8081         if (entity->declaration.storage_class == STORAGE_CLASS_REGISTER
8082                         && !may_be_register) {
8083                 errorf(&expression->base.source_position,
8084                        "address of register %s '%Y' requested",
8085                        get_entity_kind_name(entity->kind), entity->base.symbol);
8086         }
8087
8088         if (entity->kind == ENTITY_VARIABLE) {
8089                 entity->variable.address_taken = true;
8090         } else {
8091                 assert(entity->kind == ENTITY_PARAMETER);
8092                 entity->parameter.address_taken = true;
8093         }
8094 }
8095
8096 /**
8097  * Check the semantic of the address taken expression.
8098  */
8099 static void semantic_take_addr(unary_expression_t *expression)
8100 {
8101         expression_t *value = expression->value;
8102         value->base.type    = revert_automatic_type_conversion(value);
8103
8104         type_t *orig_type = value->base.type;
8105         type_t *type      = skip_typeref(orig_type);
8106         if (!is_type_valid(type))
8107                 return;
8108
8109         /* §6.5.3.2 */
8110         if (!is_lvalue(value)) {
8111                 errorf(&expression->base.source_position, "'&' requires an lvalue");
8112         }
8113         if (type->kind == TYPE_BITFIELD) {
8114                 errorf(&expression->base.source_position,
8115                        "'&' not allowed on object with bitfield type '%T'",
8116                        type);
8117         }
8118
8119         set_address_taken(value, false);
8120
8121         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8122 }
8123
8124 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8125 static expression_t *parse_##unexpression_type(void)                         \
8126 {                                                                            \
8127         expression_t *unary_expression                                           \
8128                 = allocate_expression_zero(unexpression_type);                       \
8129         eat(token_type);                                                         \
8130         unary_expression->unary.value = parse_subexpression(PREC_UNARY);         \
8131                                                                                  \
8132         sfunc(&unary_expression->unary);                                         \
8133                                                                                  \
8134         return unary_expression;                                                 \
8135 }
8136
8137 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8138                                semantic_unexpr_arithmetic)
8139 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8140                                semantic_unexpr_plus)
8141 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8142                                semantic_not)
8143 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8144                                semantic_dereference)
8145 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8146                                semantic_take_addr)
8147 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8148                                semantic_unexpr_integer)
8149 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8150                                semantic_incdec)
8151 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8152                                semantic_incdec)
8153
8154 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8155                                                sfunc)                         \
8156 static expression_t *parse_##unexpression_type(expression_t *left)            \
8157 {                                                                             \
8158         expression_t *unary_expression                                            \
8159                 = allocate_expression_zero(unexpression_type);                        \
8160         eat(token_type);                                                          \
8161         unary_expression->unary.value = left;                                     \
8162                                                                                   \
8163         sfunc(&unary_expression->unary);                                          \
8164                                                                               \
8165         return unary_expression;                                                  \
8166 }
8167
8168 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8169                                        EXPR_UNARY_POSTFIX_INCREMENT,
8170                                        semantic_incdec)
8171 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8172                                        EXPR_UNARY_POSTFIX_DECREMENT,
8173                                        semantic_incdec)
8174
8175 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8176 {
8177         /* TODO: handle complex + imaginary types */
8178
8179         type_left  = get_unqualified_type(type_left);
8180         type_right = get_unqualified_type(type_right);
8181
8182         /* §6.3.1.8 Usual arithmetic conversions */
8183         if (type_left == type_long_double || type_right == type_long_double) {
8184                 return type_long_double;
8185         } else if (type_left == type_double || type_right == type_double) {
8186                 return type_double;
8187         } else if (type_left == type_float || type_right == type_float) {
8188                 return type_float;
8189         }
8190
8191         type_left  = promote_integer(type_left);
8192         type_right = promote_integer(type_right);
8193
8194         if (type_left == type_right)
8195                 return type_left;
8196
8197         bool const signed_left  = is_type_signed(type_left);
8198         bool const signed_right = is_type_signed(type_right);
8199         int const  rank_left    = get_rank(type_left);
8200         int const  rank_right   = get_rank(type_right);
8201
8202         if (signed_left == signed_right)
8203                 return rank_left >= rank_right ? type_left : type_right;
8204
8205         int     s_rank;
8206         int     u_rank;
8207         type_t *s_type;
8208         type_t *u_type;
8209         if (signed_left) {
8210                 s_rank = rank_left;
8211                 s_type = type_left;
8212                 u_rank = rank_right;
8213                 u_type = type_right;
8214         } else {
8215                 s_rank = rank_right;
8216                 s_type = type_right;
8217                 u_rank = rank_left;
8218                 u_type = type_left;
8219         }
8220
8221         if (u_rank >= s_rank)
8222                 return u_type;
8223
8224         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8225          * easier here... */
8226         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8227                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8228                 return s_type;
8229
8230         switch (s_rank) {
8231                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8232                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8233                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8234
8235                 default: panic("invalid atomic type");
8236         }
8237 }
8238
8239 /**
8240  * Check the semantic restrictions for a binary expression.
8241  */
8242 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8243 {
8244         expression_t *const left            = expression->left;
8245         expression_t *const right           = expression->right;
8246         type_t       *const orig_type_left  = left->base.type;
8247         type_t       *const orig_type_right = right->base.type;
8248         type_t       *const type_left       = skip_typeref(orig_type_left);
8249         type_t       *const type_right      = skip_typeref(orig_type_right);
8250
8251         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8252                 /* TODO: improve error message */
8253                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8254                         errorf(&expression->base.source_position,
8255                                "operation needs arithmetic types");
8256                 }
8257                 return;
8258         }
8259
8260         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8261         expression->left      = create_implicit_cast(left, arithmetic_type);
8262         expression->right     = create_implicit_cast(right, arithmetic_type);
8263         expression->base.type = arithmetic_type;
8264 }
8265
8266 static void semantic_binexpr_integer(binary_expression_t *const expression)
8267 {
8268         expression_t *const left            = expression->left;
8269         expression_t *const right           = expression->right;
8270         type_t       *const orig_type_left  = left->base.type;
8271         type_t       *const orig_type_right = right->base.type;
8272         type_t       *const type_left       = skip_typeref(orig_type_left);
8273         type_t       *const type_right      = skip_typeref(orig_type_right);
8274
8275         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8276                 /* TODO: improve error message */
8277                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8278                         errorf(&expression->base.source_position,
8279                                "operation needs integer types");
8280                 }
8281                 return;
8282         }
8283
8284         type_t *const result_type = semantic_arithmetic(type_left, type_right);
8285         expression->left      = create_implicit_cast(left, result_type);
8286         expression->right     = create_implicit_cast(right, result_type);
8287         expression->base.type = result_type;
8288 }
8289
8290 static void warn_div_by_zero(binary_expression_t const *const expression)
8291 {
8292         if (!warning.div_by_zero ||
8293             !is_type_integer(expression->base.type))
8294                 return;
8295
8296         expression_t const *const right = expression->right;
8297         /* The type of the right operand can be different for /= */
8298         if (is_type_integer(right->base.type)                    &&
8299             is_constant_expression(right) == EXPR_CLASS_CONSTANT &&
8300             !fold_constant_to_bool(right)) {
8301                 warningf(&expression->base.source_position, "division by zero");
8302         }
8303 }
8304
8305 /**
8306  * Check the semantic restrictions for a div/mod expression.
8307  */
8308 static void semantic_divmod_arithmetic(binary_expression_t *expression)
8309 {
8310         semantic_binexpr_arithmetic(expression);
8311         warn_div_by_zero(expression);
8312 }
8313
8314 static void warn_addsub_in_shift(const expression_t *const expr)
8315 {
8316         if (expr->base.parenthesized)
8317                 return;
8318
8319         char op;
8320         switch (expr->kind) {
8321                 case EXPR_BINARY_ADD: op = '+'; break;
8322                 case EXPR_BINARY_SUB: op = '-'; break;
8323                 default:              return;
8324         }
8325
8326         warningf(&expr->base.source_position,
8327                         "suggest parentheses around '%c' inside shift", op);
8328 }
8329
8330 static bool semantic_shift(binary_expression_t *expression)
8331 {
8332         expression_t *const left            = expression->left;
8333         expression_t *const right           = expression->right;
8334         type_t       *const orig_type_left  = left->base.type;
8335         type_t       *const orig_type_right = right->base.type;
8336         type_t       *      type_left       = skip_typeref(orig_type_left);
8337         type_t       *      type_right      = skip_typeref(orig_type_right);
8338
8339         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8340                 /* TODO: improve error message */
8341                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8342                         errorf(&expression->base.source_position,
8343                                "operands of shift operation must have integer types");
8344                 }
8345                 return false;
8346         }
8347
8348         type_left = promote_integer(type_left);
8349
8350         if (is_constant_expression(right) == EXPR_CLASS_CONSTANT) {
8351                 long count = fold_constant_to_int(right);
8352                 if (count < 0) {
8353                         warningf(&right->base.source_position,
8354                                         "shift count must be non-negative");
8355                 } else if ((unsigned long)count >=
8356                                 get_atomic_type_size(type_left->atomic.akind) * 8) {
8357                         warningf(&right->base.source_position,
8358                                         "shift count must be less than type width");
8359                 }
8360         }
8361
8362         type_right        = promote_integer(type_right);
8363         expression->right = create_implicit_cast(right, type_right);
8364
8365         return true;
8366 }
8367
8368 static void semantic_shift_op(binary_expression_t *expression)
8369 {
8370         expression_t *const left  = expression->left;
8371         expression_t *const right = expression->right;
8372
8373         if (!semantic_shift(expression))
8374                 return;
8375
8376         if (warning.parentheses) {
8377                 warn_addsub_in_shift(left);
8378                 warn_addsub_in_shift(right);
8379         }
8380
8381         type_t *const orig_type_left = left->base.type;
8382         type_t *      type_left      = skip_typeref(orig_type_left);
8383
8384         type_left             = promote_integer(type_left);
8385         expression->left      = create_implicit_cast(left, type_left);
8386         expression->base.type = type_left;
8387 }
8388
8389 static void semantic_add(binary_expression_t *expression)
8390 {
8391         expression_t *const left            = expression->left;
8392         expression_t *const right           = expression->right;
8393         type_t       *const orig_type_left  = left->base.type;
8394         type_t       *const orig_type_right = right->base.type;
8395         type_t       *const type_left       = skip_typeref(orig_type_left);
8396         type_t       *const type_right      = skip_typeref(orig_type_right);
8397
8398         /* §6.5.6 */
8399         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8400                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8401                 expression->left  = create_implicit_cast(left, arithmetic_type);
8402                 expression->right = create_implicit_cast(right, arithmetic_type);
8403                 expression->base.type = arithmetic_type;
8404         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8405                 check_pointer_arithmetic(&expression->base.source_position,
8406                                          type_left, orig_type_left);
8407                 expression->base.type = type_left;
8408         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8409                 check_pointer_arithmetic(&expression->base.source_position,
8410                                          type_right, orig_type_right);
8411                 expression->base.type = type_right;
8412         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8413                 errorf(&expression->base.source_position,
8414                        "invalid operands to binary + ('%T', '%T')",
8415                        orig_type_left, orig_type_right);
8416         }
8417 }
8418
8419 static void semantic_sub(binary_expression_t *expression)
8420 {
8421         expression_t            *const left            = expression->left;
8422         expression_t            *const right           = expression->right;
8423         type_t                  *const orig_type_left  = left->base.type;
8424         type_t                  *const orig_type_right = right->base.type;
8425         type_t                  *const type_left       = skip_typeref(orig_type_left);
8426         type_t                  *const type_right      = skip_typeref(orig_type_right);
8427         source_position_t const *const pos             = &expression->base.source_position;
8428
8429         /* §5.6.5 */
8430         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8431                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8432                 expression->left        = create_implicit_cast(left, arithmetic_type);
8433                 expression->right       = create_implicit_cast(right, arithmetic_type);
8434                 expression->base.type =  arithmetic_type;
8435         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8436                 check_pointer_arithmetic(&expression->base.source_position,
8437                                          type_left, orig_type_left);
8438                 expression->base.type = type_left;
8439         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8440                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8441                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8442                 if (!types_compatible(unqual_left, unqual_right)) {
8443                         errorf(pos,
8444                                "subtracting pointers to incompatible types '%T' and '%T'",
8445                                orig_type_left, orig_type_right);
8446                 } else if (!is_type_object(unqual_left)) {
8447                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8448                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8449                                        orig_type_left);
8450                         } else if (warning.other) {
8451                                 warningf(pos, "subtracting pointers to void");
8452                         }
8453                 }
8454                 expression->base.type = type_ptrdiff_t;
8455         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8456                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
8457                        orig_type_left, orig_type_right);
8458         }
8459 }
8460
8461 static void warn_string_literal_address(expression_t const* expr)
8462 {
8463         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8464                 expr = expr->unary.value;
8465                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8466                         return;
8467                 expr = expr->unary.value;
8468         }
8469
8470         if (expr->kind == EXPR_STRING_LITERAL
8471                         || expr->kind == EXPR_WIDE_STRING_LITERAL) {
8472                 warningf(&expr->base.source_position,
8473                         "comparison with string literal results in unspecified behaviour");
8474         }
8475 }
8476
8477 static void warn_comparison_in_comparison(const expression_t *const expr)
8478 {
8479         if (expr->base.parenthesized)
8480                 return;
8481         switch (expr->base.kind) {
8482                 case EXPR_BINARY_LESS:
8483                 case EXPR_BINARY_GREATER:
8484                 case EXPR_BINARY_LESSEQUAL:
8485                 case EXPR_BINARY_GREATEREQUAL:
8486                 case EXPR_BINARY_NOTEQUAL:
8487                 case EXPR_BINARY_EQUAL:
8488                         warningf(&expr->base.source_position,
8489                                         "comparisons like 'x <= y < z' do not have their mathematical meaning");
8490                         break;
8491                 default:
8492                         break;
8493         }
8494 }
8495
8496 static bool maybe_negative(expression_t const *const expr)
8497 {
8498         switch (is_constant_expression(expr)) {
8499                 case EXPR_CLASS_ERROR:    return false;
8500                 case EXPR_CLASS_CONSTANT: return fold_constant_to_int(expr) < 0;
8501                 default:                  return true;
8502         }
8503 }
8504
8505 /**
8506  * Check the semantics of comparison expressions.
8507  *
8508  * @param expression   The expression to check.
8509  */
8510 static void semantic_comparison(binary_expression_t *expression)
8511 {
8512         expression_t *left  = expression->left;
8513         expression_t *right = expression->right;
8514
8515         if (warning.address) {
8516                 warn_string_literal_address(left);
8517                 warn_string_literal_address(right);
8518
8519                 expression_t const* const func_left = get_reference_address(left);
8520                 if (func_left != NULL && is_null_pointer_constant(right)) {
8521                         warningf(&expression->base.source_position,
8522                                  "the address of '%Y' will never be NULL",
8523                                  func_left->reference.entity->base.symbol);
8524                 }
8525
8526                 expression_t const* const func_right = get_reference_address(right);
8527                 if (func_right != NULL && is_null_pointer_constant(right)) {
8528                         warningf(&expression->base.source_position,
8529                                  "the address of '%Y' will never be NULL",
8530                                  func_right->reference.entity->base.symbol);
8531                 }
8532         }
8533
8534         if (warning.parentheses) {
8535                 warn_comparison_in_comparison(left);
8536                 warn_comparison_in_comparison(right);
8537         }
8538
8539         type_t *orig_type_left  = left->base.type;
8540         type_t *orig_type_right = right->base.type;
8541         type_t *type_left       = skip_typeref(orig_type_left);
8542         type_t *type_right      = skip_typeref(orig_type_right);
8543
8544         /* TODO non-arithmetic types */
8545         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8546                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8547
8548                 /* test for signed vs unsigned compares */
8549                 if (warning.sign_compare && is_type_integer(arithmetic_type)) {
8550                         bool const signed_left  = is_type_signed(type_left);
8551                         bool const signed_right = is_type_signed(type_right);
8552                         if (signed_left != signed_right) {
8553                                 /* FIXME long long needs better const folding magic */
8554                                 /* TODO check whether constant value can be represented by other type */
8555                                 if ((signed_left  && maybe_negative(left)) ||
8556                                                 (signed_right && maybe_negative(right))) {
8557                                         warningf(&expression->base.source_position,
8558                                                         "comparison between signed and unsigned");
8559                                 }
8560                         }
8561                 }
8562
8563                 expression->left        = create_implicit_cast(left, arithmetic_type);
8564                 expression->right       = create_implicit_cast(right, arithmetic_type);
8565                 expression->base.type   = arithmetic_type;
8566                 if (warning.float_equal &&
8567                     (expression->base.kind == EXPR_BINARY_EQUAL ||
8568                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
8569                     is_type_float(arithmetic_type)) {
8570                         warningf(&expression->base.source_position,
8571                                  "comparing floating point with == or != is unsafe");
8572                 }
8573         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8574                 /* TODO check compatibility */
8575         } else if (is_type_pointer(type_left)) {
8576                 expression->right = create_implicit_cast(right, type_left);
8577         } else if (is_type_pointer(type_right)) {
8578                 expression->left = create_implicit_cast(left, type_right);
8579         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8580                 type_error_incompatible("invalid operands in comparison",
8581                                         &expression->base.source_position,
8582                                         type_left, type_right);
8583         }
8584         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8585 }
8586
8587 /**
8588  * Checks if a compound type has constant fields.
8589  */
8590 static bool has_const_fields(const compound_type_t *type)
8591 {
8592         compound_t *compound = type->compound;
8593         entity_t   *entry    = compound->members.entities;
8594
8595         for (; entry != NULL; entry = entry->base.next) {
8596                 if (!is_declaration(entry))
8597                         continue;
8598
8599                 const type_t *decl_type = skip_typeref(entry->declaration.type);
8600                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
8601                         return true;
8602         }
8603
8604         return false;
8605 }
8606
8607 static bool is_valid_assignment_lhs(expression_t const* const left)
8608 {
8609         type_t *const orig_type_left = revert_automatic_type_conversion(left);
8610         type_t *const type_left      = skip_typeref(orig_type_left);
8611
8612         if (!is_lvalue(left)) {
8613                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
8614                        left);
8615                 return false;
8616         }
8617
8618         if (left->kind == EXPR_REFERENCE
8619                         && left->reference.entity->kind == ENTITY_FUNCTION) {
8620                 errorf(HERE, "cannot assign to function '%E'", left);
8621                 return false;
8622         }
8623
8624         if (is_type_array(type_left)) {
8625                 errorf(HERE, "cannot assign to array '%E'", left);
8626                 return false;
8627         }
8628         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
8629                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
8630                        orig_type_left);
8631                 return false;
8632         }
8633         if (is_type_incomplete(type_left)) {
8634                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
8635                        left, orig_type_left);
8636                 return false;
8637         }
8638         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
8639                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
8640                        left, orig_type_left);
8641                 return false;
8642         }
8643
8644         return true;
8645 }
8646
8647 static void semantic_arithmetic_assign(binary_expression_t *expression)
8648 {
8649         expression_t *left            = expression->left;
8650         expression_t *right           = expression->right;
8651         type_t       *orig_type_left  = left->base.type;
8652         type_t       *orig_type_right = right->base.type;
8653
8654         if (!is_valid_assignment_lhs(left))
8655                 return;
8656
8657         type_t *type_left  = skip_typeref(orig_type_left);
8658         type_t *type_right = skip_typeref(orig_type_right);
8659
8660         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8661                 /* TODO: improve error message */
8662                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8663                         errorf(&expression->base.source_position,
8664                                "operation needs arithmetic types");
8665                 }
8666                 return;
8667         }
8668
8669         /* combined instructions are tricky. We can't create an implicit cast on
8670          * the left side, because we need the uncasted form for the store.
8671          * The ast2firm pass has to know that left_type must be right_type
8672          * for the arithmetic operation and create a cast by itself */
8673         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8674         expression->right       = create_implicit_cast(right, arithmetic_type);
8675         expression->base.type   = type_left;
8676 }
8677
8678 static void semantic_divmod_assign(binary_expression_t *expression)
8679 {
8680         semantic_arithmetic_assign(expression);
8681         warn_div_by_zero(expression);
8682 }
8683
8684 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
8685 {
8686         expression_t *const left            = expression->left;
8687         expression_t *const right           = expression->right;
8688         type_t       *const orig_type_left  = left->base.type;
8689         type_t       *const orig_type_right = right->base.type;
8690         type_t       *const type_left       = skip_typeref(orig_type_left);
8691         type_t       *const type_right      = skip_typeref(orig_type_right);
8692
8693         if (!is_valid_assignment_lhs(left))
8694                 return;
8695
8696         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8697                 /* combined instructions are tricky. We can't create an implicit cast on
8698                  * the left side, because we need the uncasted form for the store.
8699                  * The ast2firm pass has to know that left_type must be right_type
8700                  * for the arithmetic operation and create a cast by itself */
8701                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
8702                 expression->right     = create_implicit_cast(right, arithmetic_type);
8703                 expression->base.type = type_left;
8704         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8705                 check_pointer_arithmetic(&expression->base.source_position,
8706                                          type_left, orig_type_left);
8707                 expression->base.type = type_left;
8708         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8709                 errorf(&expression->base.source_position,
8710                        "incompatible types '%T' and '%T' in assignment",
8711                        orig_type_left, orig_type_right);
8712         }
8713 }
8714
8715 static void semantic_integer_assign(binary_expression_t *expression)
8716 {
8717         expression_t *left            = expression->left;
8718         expression_t *right           = expression->right;
8719         type_t       *orig_type_left  = left->base.type;
8720         type_t       *orig_type_right = right->base.type;
8721
8722         if (!is_valid_assignment_lhs(left))
8723                 return;
8724
8725         type_t *type_left  = skip_typeref(orig_type_left);
8726         type_t *type_right = skip_typeref(orig_type_right);
8727
8728         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8729                 /* TODO: improve error message */
8730                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8731                         errorf(&expression->base.source_position,
8732                                "operation needs integer types");
8733                 }
8734                 return;
8735         }
8736
8737         /* combined instructions are tricky. We can't create an implicit cast on
8738          * the left side, because we need the uncasted form for the store.
8739          * The ast2firm pass has to know that left_type must be right_type
8740          * for the arithmetic operation and create a cast by itself */
8741         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8742         expression->right       = create_implicit_cast(right, arithmetic_type);
8743         expression->base.type   = type_left;
8744 }
8745
8746 static void semantic_shift_assign(binary_expression_t *expression)
8747 {
8748         expression_t *left           = expression->left;
8749
8750         if (!is_valid_assignment_lhs(left))
8751                 return;
8752
8753         if (!semantic_shift(expression))
8754                 return;
8755
8756         expression->base.type = skip_typeref(left->base.type);
8757 }
8758
8759 static void warn_logical_and_within_or(const expression_t *const expr)
8760 {
8761         if (expr->base.kind != EXPR_BINARY_LOGICAL_AND)
8762                 return;
8763         if (expr->base.parenthesized)
8764                 return;
8765         warningf(&expr->base.source_position,
8766                         "suggest parentheses around && within ||");
8767 }
8768
8769 /**
8770  * Check the semantic restrictions of a logical expression.
8771  */
8772 static void semantic_logical_op(binary_expression_t *expression)
8773 {
8774         /* §6.5.13:2  Each of the operands shall have scalar type.
8775          * §6.5.14:2  Each of the operands shall have scalar type. */
8776         semantic_condition(expression->left,   "left operand of logical operator");
8777         semantic_condition(expression->right, "right operand of logical operator");
8778         if (expression->base.kind == EXPR_BINARY_LOGICAL_OR &&
8779                         warning.parentheses) {
8780                 warn_logical_and_within_or(expression->left);
8781                 warn_logical_and_within_or(expression->right);
8782         }
8783         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8784 }
8785
8786 /**
8787  * Check the semantic restrictions of a binary assign expression.
8788  */
8789 static void semantic_binexpr_assign(binary_expression_t *expression)
8790 {
8791         expression_t *left           = expression->left;
8792         type_t       *orig_type_left = left->base.type;
8793
8794         if (!is_valid_assignment_lhs(left))
8795                 return;
8796
8797         assign_error_t error = semantic_assign(orig_type_left, expression->right);
8798         report_assign_error(error, orig_type_left, expression->right,
8799                         "assignment", &left->base.source_position);
8800         expression->right = create_implicit_cast(expression->right, orig_type_left);
8801         expression->base.type = orig_type_left;
8802 }
8803
8804 /**
8805  * Determine if the outermost operation (or parts thereof) of the given
8806  * expression has no effect in order to generate a warning about this fact.
8807  * Therefore in some cases this only examines some of the operands of the
8808  * expression (see comments in the function and examples below).
8809  * Examples:
8810  *   f() + 23;    // warning, because + has no effect
8811  *   x || f();    // no warning, because x controls execution of f()
8812  *   x ? y : f(); // warning, because y has no effect
8813  *   (void)x;     // no warning to be able to suppress the warning
8814  * This function can NOT be used for an "expression has definitely no effect"-
8815  * analysis. */
8816 static bool expression_has_effect(const expression_t *const expr)
8817 {
8818         switch (expr->kind) {
8819                 case EXPR_UNKNOWN:                    break;
8820                 case EXPR_INVALID:                    return true; /* do NOT warn */
8821                 case EXPR_REFERENCE:                  return false;
8822                 case EXPR_REFERENCE_ENUM_VALUE:       return false;
8823                 case EXPR_LABEL_ADDRESS:              return false;
8824
8825                 /* suppress the warning for microsoft __noop operations */
8826                 case EXPR_LITERAL_MS_NOOP:            return true;
8827                 case EXPR_LITERAL_BOOLEAN:
8828                 case EXPR_LITERAL_CHARACTER:
8829                 case EXPR_LITERAL_WIDE_CHARACTER:
8830                 case EXPR_LITERAL_INTEGER:
8831                 case EXPR_LITERAL_INTEGER_OCTAL:
8832                 case EXPR_LITERAL_INTEGER_HEXADECIMAL:
8833                 case EXPR_LITERAL_FLOATINGPOINT:
8834                 case EXPR_LITERAL_FLOATINGPOINT_HEXADECIMAL: return false;
8835                 case EXPR_STRING_LITERAL:             return false;
8836                 case EXPR_WIDE_STRING_LITERAL:        return false;
8837
8838                 case EXPR_CALL: {
8839                         const call_expression_t *const call = &expr->call;
8840                         if (call->function->kind != EXPR_REFERENCE)
8841                                 return true;
8842
8843                         switch (call->function->reference.entity->function.btk) {
8844                                 /* FIXME: which builtins have no effect? */
8845                                 default:                      return true;
8846                         }
8847                 }
8848
8849                 /* Generate the warning if either the left or right hand side of a
8850                  * conditional expression has no effect */
8851                 case EXPR_CONDITIONAL: {
8852                         conditional_expression_t const *const cond = &expr->conditional;
8853                         expression_t             const *const t    = cond->true_expression;
8854                         return
8855                                 (t == NULL || expression_has_effect(t)) &&
8856                                 expression_has_effect(cond->false_expression);
8857                 }
8858
8859                 case EXPR_SELECT:                     return false;
8860                 case EXPR_ARRAY_ACCESS:               return false;
8861                 case EXPR_SIZEOF:                     return false;
8862                 case EXPR_CLASSIFY_TYPE:              return false;
8863                 case EXPR_ALIGNOF:                    return false;
8864
8865                 case EXPR_FUNCNAME:                   return false;
8866                 case EXPR_BUILTIN_CONSTANT_P:         return false;
8867                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P: return false;
8868                 case EXPR_OFFSETOF:                   return false;
8869                 case EXPR_VA_START:                   return true;
8870                 case EXPR_VA_ARG:                     return true;
8871                 case EXPR_VA_COPY:                    return true;
8872                 case EXPR_STATEMENT:                  return true; // TODO
8873                 case EXPR_COMPOUND_LITERAL:           return false;
8874
8875                 case EXPR_UNARY_NEGATE:               return false;
8876                 case EXPR_UNARY_PLUS:                 return false;
8877                 case EXPR_UNARY_BITWISE_NEGATE:       return false;
8878                 case EXPR_UNARY_NOT:                  return false;
8879                 case EXPR_UNARY_DEREFERENCE:          return false;
8880                 case EXPR_UNARY_TAKE_ADDRESS:         return false;
8881                 case EXPR_UNARY_POSTFIX_INCREMENT:    return true;
8882                 case EXPR_UNARY_POSTFIX_DECREMENT:    return true;
8883                 case EXPR_UNARY_PREFIX_INCREMENT:     return true;
8884                 case EXPR_UNARY_PREFIX_DECREMENT:     return true;
8885
8886                 /* Treat void casts as if they have an effect in order to being able to
8887                  * suppress the warning */
8888                 case EXPR_UNARY_CAST: {
8889                         type_t *const type = skip_typeref(expr->base.type);
8890                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
8891                 }
8892
8893                 case EXPR_UNARY_CAST_IMPLICIT:        return true;
8894                 case EXPR_UNARY_ASSUME:               return true;
8895                 case EXPR_UNARY_DELETE:               return true;
8896                 case EXPR_UNARY_DELETE_ARRAY:         return true;
8897                 case EXPR_UNARY_THROW:                return true;
8898
8899                 case EXPR_BINARY_ADD:                 return false;
8900                 case EXPR_BINARY_SUB:                 return false;
8901                 case EXPR_BINARY_MUL:                 return false;
8902                 case EXPR_BINARY_DIV:                 return false;
8903                 case EXPR_BINARY_MOD:                 return false;
8904                 case EXPR_BINARY_EQUAL:               return false;
8905                 case EXPR_BINARY_NOTEQUAL:            return false;
8906                 case EXPR_BINARY_LESS:                return false;
8907                 case EXPR_BINARY_LESSEQUAL:           return false;
8908                 case EXPR_BINARY_GREATER:             return false;
8909                 case EXPR_BINARY_GREATEREQUAL:        return false;
8910                 case EXPR_BINARY_BITWISE_AND:         return false;
8911                 case EXPR_BINARY_BITWISE_OR:          return false;
8912                 case EXPR_BINARY_BITWISE_XOR:         return false;
8913                 case EXPR_BINARY_SHIFTLEFT:           return false;
8914                 case EXPR_BINARY_SHIFTRIGHT:          return false;
8915                 case EXPR_BINARY_ASSIGN:              return true;
8916                 case EXPR_BINARY_MUL_ASSIGN:          return true;
8917                 case EXPR_BINARY_DIV_ASSIGN:          return true;
8918                 case EXPR_BINARY_MOD_ASSIGN:          return true;
8919                 case EXPR_BINARY_ADD_ASSIGN:          return true;
8920                 case EXPR_BINARY_SUB_ASSIGN:          return true;
8921                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:    return true;
8922                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:   return true;
8923                 case EXPR_BINARY_BITWISE_AND_ASSIGN:  return true;
8924                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:  return true;
8925                 case EXPR_BINARY_BITWISE_OR_ASSIGN:   return true;
8926
8927                 /* Only examine the right hand side of && and ||, because the left hand
8928                  * side already has the effect of controlling the execution of the right
8929                  * hand side */
8930                 case EXPR_BINARY_LOGICAL_AND:
8931                 case EXPR_BINARY_LOGICAL_OR:
8932                 /* Only examine the right hand side of a comma expression, because the left
8933                  * hand side has a separate warning */
8934                 case EXPR_BINARY_COMMA:
8935                         return expression_has_effect(expr->binary.right);
8936
8937                 case EXPR_BINARY_ISGREATER:           return false;
8938                 case EXPR_BINARY_ISGREATEREQUAL:      return false;
8939                 case EXPR_BINARY_ISLESS:              return false;
8940                 case EXPR_BINARY_ISLESSEQUAL:         return false;
8941                 case EXPR_BINARY_ISLESSGREATER:       return false;
8942                 case EXPR_BINARY_ISUNORDERED:         return false;
8943         }
8944
8945         internal_errorf(HERE, "unexpected expression");
8946 }
8947
8948 static void semantic_comma(binary_expression_t *expression)
8949 {
8950         if (warning.unused_value) {
8951                 const expression_t *const left = expression->left;
8952                 if (!expression_has_effect(left)) {
8953                         warningf(&left->base.source_position,
8954                                  "left-hand operand of comma expression has no effect");
8955                 }
8956         }
8957         expression->base.type = expression->right->base.type;
8958 }
8959
8960 /**
8961  * @param prec_r precedence of the right operand
8962  */
8963 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
8964 static expression_t *parse_##binexpression_type(expression_t *left)          \
8965 {                                                                            \
8966         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
8967         binexpr->binary.left  = left;                                            \
8968         eat(token_type);                                                         \
8969                                                                              \
8970         expression_t *right = parse_subexpression(prec_r);                       \
8971                                                                              \
8972         binexpr->binary.right = right;                                           \
8973         sfunc(&binexpr->binary);                                                 \
8974                                                                              \
8975         return binexpr;                                                          \
8976 }
8977
8978 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
8979 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
8980 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
8981 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
8982 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
8983 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
8984 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
8985 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
8986 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
8987 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
8988 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
8989 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
8990 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
8991 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_integer)
8992 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_integer)
8993 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_integer)
8994 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
8995 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
8996 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
8997 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
8998 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
8999 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
9000 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9001 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
9002 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_shift_assign)
9003 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_shift_assign)
9004 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_integer_assign)
9005 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_integer_assign)
9006 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_integer_assign)
9007 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
9008
9009
9010 static expression_t *parse_subexpression(precedence_t precedence)
9011 {
9012         if (token.type < 0) {
9013                 return expected_expression_error();
9014         }
9015
9016         expression_parser_function_t *parser
9017                 = &expression_parsers[token.type];
9018         source_position_t             source_position = token.source_position;
9019         expression_t                 *left;
9020
9021         if (parser->parser != NULL) {
9022                 left = parser->parser();
9023         } else {
9024                 left = parse_primary_expression();
9025         }
9026         assert(left != NULL);
9027         left->base.source_position = source_position;
9028
9029         while (true) {
9030                 if (token.type < 0) {
9031                         return expected_expression_error();
9032                 }
9033
9034                 parser = &expression_parsers[token.type];
9035                 if (parser->infix_parser == NULL)
9036                         break;
9037                 if (parser->infix_precedence < precedence)
9038                         break;
9039
9040                 left = parser->infix_parser(left);
9041
9042                 assert(left != NULL);
9043                 assert(left->kind != EXPR_UNKNOWN);
9044                 left->base.source_position = source_position;
9045         }
9046
9047         return left;
9048 }
9049
9050 /**
9051  * Parse an expression.
9052  */
9053 static expression_t *parse_expression(void)
9054 {
9055         return parse_subexpression(PREC_EXPRESSION);
9056 }
9057
9058 /**
9059  * Register a parser for a prefix-like operator.
9060  *
9061  * @param parser      the parser function
9062  * @param token_type  the token type of the prefix token
9063  */
9064 static void register_expression_parser(parse_expression_function parser,
9065                                        int token_type)
9066 {
9067         expression_parser_function_t *entry = &expression_parsers[token_type];
9068
9069         if (entry->parser != NULL) {
9070                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9071                 panic("trying to register multiple expression parsers for a token");
9072         }
9073         entry->parser = parser;
9074 }
9075
9076 /**
9077  * Register a parser for an infix operator with given precedence.
9078  *
9079  * @param parser      the parser function
9080  * @param token_type  the token type of the infix operator
9081  * @param precedence  the precedence of the operator
9082  */
9083 static void register_infix_parser(parse_expression_infix_function parser,
9084                                   int token_type, precedence_t precedence)
9085 {
9086         expression_parser_function_t *entry = &expression_parsers[token_type];
9087
9088         if (entry->infix_parser != NULL) {
9089                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9090                 panic("trying to register multiple infix expression parsers for a "
9091                       "token");
9092         }
9093         entry->infix_parser     = parser;
9094         entry->infix_precedence = precedence;
9095 }
9096
9097 /**
9098  * Initialize the expression parsers.
9099  */
9100 static void init_expression_parsers(void)
9101 {
9102         memset(&expression_parsers, 0, sizeof(expression_parsers));
9103
9104         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
9105         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
9106         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
9107         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
9108         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
9109         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
9110         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
9111         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
9112         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
9113         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
9114         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
9115         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
9116         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
9117         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
9118         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
9119         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
9120         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
9121         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
9122         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
9123         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
9124         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
9125         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
9126         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
9127         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
9128         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
9129         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
9130         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
9131         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
9132         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
9133         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
9134         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
9135         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
9136         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
9137         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
9138         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
9139         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
9140         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
9141
9142         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
9143         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
9144         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
9145         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
9146         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
9147         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
9148         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
9149         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
9150         register_expression_parser(parse_sizeof,                      T_sizeof);
9151         register_expression_parser(parse_alignof,                     T___alignof__);
9152         register_expression_parser(parse_extension,                   T___extension__);
9153         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
9154         register_expression_parser(parse_delete,                      T_delete);
9155         register_expression_parser(parse_throw,                       T_throw);
9156 }
9157
9158 /**
9159  * Parse a asm statement arguments specification.
9160  */
9161 static asm_argument_t *parse_asm_arguments(bool is_out)
9162 {
9163         asm_argument_t  *result = NULL;
9164         asm_argument_t **anchor = &result;
9165
9166         while (token.type == T_STRING_LITERAL || token.type == '[') {
9167                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
9168                 memset(argument, 0, sizeof(argument[0]));
9169
9170                 if (next_if('[')) {
9171                         if (token.type != T_IDENTIFIER) {
9172                                 parse_error_expected("while parsing asm argument",
9173                                                      T_IDENTIFIER, NULL);
9174                                 return NULL;
9175                         }
9176                         argument->symbol = token.symbol;
9177
9178                         expect(']', end_error);
9179                 }
9180
9181                 argument->constraints = parse_string_literals();
9182                 expect('(', end_error);
9183                 add_anchor_token(')');
9184                 expression_t *expression = parse_expression();
9185                 rem_anchor_token(')');
9186                 if (is_out) {
9187                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
9188                          * change size or type representation (e.g. int -> long is ok, but
9189                          * int -> float is not) */
9190                         if (expression->kind == EXPR_UNARY_CAST) {
9191                                 type_t      *const type = expression->base.type;
9192                                 type_kind_t  const kind = type->kind;
9193                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
9194                                         unsigned flags;
9195                                         unsigned size;
9196                                         if (kind == TYPE_ATOMIC) {
9197                                                 atomic_type_kind_t const akind = type->atomic.akind;
9198                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9199                                                 size  = get_atomic_type_size(akind);
9200                                         } else {
9201                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9202                                                 size  = get_atomic_type_size(get_intptr_kind());
9203                                         }
9204
9205                                         do {
9206                                                 expression_t *const value      = expression->unary.value;
9207                                                 type_t       *const value_type = value->base.type;
9208                                                 type_kind_t   const value_kind = value_type->kind;
9209
9210                                                 unsigned value_flags;
9211                                                 unsigned value_size;
9212                                                 if (value_kind == TYPE_ATOMIC) {
9213                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
9214                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9215                                                         value_size  = get_atomic_type_size(value_akind);
9216                                                 } else if (value_kind == TYPE_POINTER) {
9217                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9218                                                         value_size  = get_atomic_type_size(get_intptr_kind());
9219                                                 } else {
9220                                                         break;
9221                                                 }
9222
9223                                                 if (value_flags != flags || value_size != size)
9224                                                         break;
9225
9226                                                 expression = value;
9227                                         } while (expression->kind == EXPR_UNARY_CAST);
9228                                 }
9229                         }
9230
9231                         if (!is_lvalue(expression)) {
9232                                 errorf(&expression->base.source_position,
9233                                        "asm output argument is not an lvalue");
9234                         }
9235
9236                         if (argument->constraints.begin[0] == '=')
9237                                 determine_lhs_ent(expression, NULL);
9238                         else
9239                                 mark_vars_read(expression, NULL);
9240                 } else {
9241                         mark_vars_read(expression, NULL);
9242                 }
9243                 argument->expression = expression;
9244                 expect(')', end_error);
9245
9246                 set_address_taken(expression, true);
9247
9248                 *anchor = argument;
9249                 anchor  = &argument->next;
9250
9251                 if (!next_if(','))
9252                         break;
9253         }
9254
9255         return result;
9256 end_error:
9257         return NULL;
9258 }
9259
9260 /**
9261  * Parse a asm statement clobber specification.
9262  */
9263 static asm_clobber_t *parse_asm_clobbers(void)
9264 {
9265         asm_clobber_t *result  = NULL;
9266         asm_clobber_t **anchor = &result;
9267
9268         while (token.type == T_STRING_LITERAL) {
9269                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9270                 clobber->clobber       = parse_string_literals();
9271
9272                 *anchor = clobber;
9273                 anchor  = &clobber->next;
9274
9275                 if (!next_if(','))
9276                         break;
9277         }
9278
9279         return result;
9280 }
9281
9282 /**
9283  * Parse an asm statement.
9284  */
9285 static statement_t *parse_asm_statement(void)
9286 {
9287         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9288         asm_statement_t *asm_statement = &statement->asms;
9289
9290         eat(T_asm);
9291
9292         if (next_if(T_volatile))
9293                 asm_statement->is_volatile = true;
9294
9295         expect('(', end_error);
9296         add_anchor_token(')');
9297         if (token.type != T_STRING_LITERAL) {
9298                 parse_error_expected("after asm(", T_STRING_LITERAL, NULL);
9299                 goto end_of_asm;
9300         }
9301         asm_statement->asm_text = parse_string_literals();
9302
9303         add_anchor_token(':');
9304         if (!next_if(':')) {
9305                 rem_anchor_token(':');
9306                 goto end_of_asm;
9307         }
9308
9309         asm_statement->outputs = parse_asm_arguments(true);
9310         if (!next_if(':')) {
9311                 rem_anchor_token(':');
9312                 goto end_of_asm;
9313         }
9314
9315         asm_statement->inputs = parse_asm_arguments(false);
9316         if (!next_if(':')) {
9317                 rem_anchor_token(':');
9318                 goto end_of_asm;
9319         }
9320         rem_anchor_token(':');
9321
9322         asm_statement->clobbers = parse_asm_clobbers();
9323
9324 end_of_asm:
9325         rem_anchor_token(')');
9326         expect(')', end_error);
9327         expect(';', end_error);
9328
9329         if (asm_statement->outputs == NULL) {
9330                 /* GCC: An 'asm' instruction without any output operands will be treated
9331                  * identically to a volatile 'asm' instruction. */
9332                 asm_statement->is_volatile = true;
9333         }
9334
9335         return statement;
9336 end_error:
9337         return create_invalid_statement();
9338 }
9339
9340 static statement_t *parse_label_inner_statement(statement_t const *const label, char const *const label_kind)
9341 {
9342         statement_t *inner_stmt;
9343         switch (token.type) {
9344                 case '}':
9345                         errorf(&label->base.source_position, "%s at end of compound statement", label_kind);
9346                         inner_stmt = create_invalid_statement();
9347                         break;
9348
9349                 case ';':
9350                         if (label->kind == STATEMENT_LABEL) {
9351                                 /* Eat an empty statement here, to avoid the warning about an empty
9352                                  * statement after a label.  label:; is commonly used to have a label
9353                                  * before a closing brace. */
9354                                 inner_stmt = create_empty_statement();
9355                                 next_token();
9356                                 break;
9357                         }
9358                         /* FALLTHROUGH */
9359
9360                 default:
9361                         inner_stmt = parse_statement();
9362                         /* ISO/IEC 14882:1998(E) §6:1/§6.7  Declarations are statements */
9363                         if (inner_stmt->kind == STATEMENT_DECLARATION && !(c_mode & _CXX)) {
9364                                 errorf(&inner_stmt->base.source_position, "declaration after %s", label_kind);
9365                         }
9366                         break;
9367         }
9368         return inner_stmt;
9369 }
9370
9371 /**
9372  * Parse a case statement.
9373  */
9374 static statement_t *parse_case_statement(void)
9375 {
9376         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9377         source_position_t *const pos       = &statement->base.source_position;
9378
9379         eat(T_case);
9380
9381         expression_t *const expression   = parse_expression();
9382         statement->case_label.expression = expression;
9383         expression_classification_t const expr_class = is_constant_expression(expression);
9384         if (expr_class != EXPR_CLASS_CONSTANT) {
9385                 if (expr_class != EXPR_CLASS_ERROR) {
9386                         errorf(pos, "case label does not reduce to an integer constant");
9387                 }
9388                 statement->case_label.is_bad = true;
9389         } else {
9390                 long const val = fold_constant_to_int(expression);
9391                 statement->case_label.first_case = val;
9392                 statement->case_label.last_case  = val;
9393         }
9394
9395         if (GNU_MODE) {
9396                 if (next_if(T_DOTDOTDOT)) {
9397                         expression_t *const end_range   = parse_expression();
9398                         statement->case_label.end_range = end_range;
9399                         expression_classification_t const end_class = is_constant_expression(end_range);
9400                         if (end_class != EXPR_CLASS_CONSTANT) {
9401                                 if (end_class != EXPR_CLASS_ERROR) {
9402                                         errorf(pos, "case range does not reduce to an integer constant");
9403                                 }
9404                                 statement->case_label.is_bad = true;
9405                         } else {
9406                                 long const val = fold_constant_to_int(end_range);
9407                                 statement->case_label.last_case = val;
9408
9409                                 if (warning.other && val < statement->case_label.first_case) {
9410                                         statement->case_label.is_empty_range = true;
9411                                         warningf(pos, "empty range specified");
9412                                 }
9413                         }
9414                 }
9415         }
9416
9417         PUSH_PARENT(statement);
9418
9419         expect(':', end_error);
9420 end_error:
9421
9422         if (current_switch != NULL) {
9423                 if (! statement->case_label.is_bad) {
9424                         /* Check for duplicate case values */
9425                         case_label_statement_t *c = &statement->case_label;
9426                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9427                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9428                                         continue;
9429
9430                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9431                                         continue;
9432
9433                                 errorf(pos, "duplicate case value (previously used %P)",
9434                                        &l->base.source_position);
9435                                 break;
9436                         }
9437                 }
9438                 /* link all cases into the switch statement */
9439                 if (current_switch->last_case == NULL) {
9440                         current_switch->first_case      = &statement->case_label;
9441                 } else {
9442                         current_switch->last_case->next = &statement->case_label;
9443                 }
9444                 current_switch->last_case = &statement->case_label;
9445         } else {
9446                 errorf(pos, "case label not within a switch statement");
9447         }
9448
9449         statement->case_label.statement = parse_label_inner_statement(statement, "case label");
9450
9451         POP_PARENT;
9452         return statement;
9453 }
9454
9455 /**
9456  * Parse a default statement.
9457  */
9458 static statement_t *parse_default_statement(void)
9459 {
9460         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9461
9462         eat(T_default);
9463
9464         PUSH_PARENT(statement);
9465
9466         expect(':', end_error);
9467 end_error:
9468
9469         if (current_switch != NULL) {
9470                 const case_label_statement_t *def_label = current_switch->default_label;
9471                 if (def_label != NULL) {
9472                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9473                                &def_label->base.source_position);
9474                 } else {
9475                         current_switch->default_label = &statement->case_label;
9476
9477                         /* link all cases into the switch statement */
9478                         if (current_switch->last_case == NULL) {
9479                                 current_switch->first_case      = &statement->case_label;
9480                         } else {
9481                                 current_switch->last_case->next = &statement->case_label;
9482                         }
9483                         current_switch->last_case = &statement->case_label;
9484                 }
9485         } else {
9486                 errorf(&statement->base.source_position,
9487                         "'default' label not within a switch statement");
9488         }
9489
9490         statement->case_label.statement = parse_label_inner_statement(statement, "default label");
9491
9492         POP_PARENT;
9493         return statement;
9494 }
9495
9496 /**
9497  * Parse a label statement.
9498  */
9499 static statement_t *parse_label_statement(void)
9500 {
9501         assert(token.type == T_IDENTIFIER);
9502         symbol_t *symbol = token.symbol;
9503         label_t  *label  = get_label(symbol);
9504
9505         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9506         statement->label.label       = label;
9507
9508         next_token();
9509
9510         PUSH_PARENT(statement);
9511
9512         /* if statement is already set then the label is defined twice,
9513          * otherwise it was just mentioned in a goto/local label declaration so far
9514          */
9515         if (label->statement != NULL) {
9516                 errorf(HERE, "duplicate label '%Y' (declared %P)",
9517                        symbol, &label->base.source_position);
9518         } else {
9519                 label->base.source_position = token.source_position;
9520                 label->statement            = statement;
9521         }
9522
9523         eat(':');
9524
9525         statement->label.statement = parse_label_inner_statement(statement, "label");
9526
9527         /* remember the labels in a list for later checking */
9528         *label_anchor = &statement->label;
9529         label_anchor  = &statement->label.next;
9530
9531         POP_PARENT;
9532         return statement;
9533 }
9534
9535 /**
9536  * Parse an if statement.
9537  */
9538 static statement_t *parse_if(void)
9539 {
9540         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
9541
9542         eat(T_if);
9543
9544         PUSH_PARENT(statement);
9545
9546         add_anchor_token('{');
9547
9548         expect('(', end_error);
9549         add_anchor_token(')');
9550         expression_t *const expr = parse_expression();
9551         statement->ifs.condition = expr;
9552         /* §6.8.4.1:1  The controlling expression of an if statement shall have
9553          *             scalar type. */
9554         semantic_condition(expr, "condition of 'if'-statment");
9555         mark_vars_read(expr, NULL);
9556         rem_anchor_token(')');
9557         expect(')', end_error);
9558
9559 end_error:
9560         rem_anchor_token('{');
9561
9562         add_anchor_token(T_else);
9563         statement_t *const true_stmt = parse_statement();
9564         statement->ifs.true_statement = true_stmt;
9565         rem_anchor_token(T_else);
9566
9567         if (next_if(T_else)) {
9568                 statement->ifs.false_statement = parse_statement();
9569         } else if (warning.parentheses &&
9570                         true_stmt->kind == STATEMENT_IF &&
9571                         true_stmt->ifs.false_statement != NULL) {
9572                 warningf(&true_stmt->base.source_position,
9573                                 "suggest explicit braces to avoid ambiguous 'else'");
9574         }
9575
9576         POP_PARENT;
9577         return statement;
9578 }
9579
9580 /**
9581  * Check that all enums are handled in a switch.
9582  *
9583  * @param statement  the switch statement to check
9584  */
9585 static void check_enum_cases(const switch_statement_t *statement)
9586 {
9587         const type_t *type = skip_typeref(statement->expression->base.type);
9588         if (! is_type_enum(type))
9589                 return;
9590         const enum_type_t *enumt = &type->enumt;
9591
9592         /* if we have a default, no warnings */
9593         if (statement->default_label != NULL)
9594                 return;
9595
9596         /* FIXME: calculation of value should be done while parsing */
9597         /* TODO: quadratic algorithm here. Change to an n log n one */
9598         long            last_value = -1;
9599         const entity_t *entry      = enumt->enume->base.next;
9600         for (; entry != NULL && entry->kind == ENTITY_ENUM_VALUE;
9601              entry = entry->base.next) {
9602                 const expression_t *expression = entry->enum_value.value;
9603                 long                value      = expression != NULL ? fold_constant_to_int(expression) : last_value + 1;
9604                 bool                found      = false;
9605                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
9606                         if (l->expression == NULL)
9607                                 continue;
9608                         if (l->first_case <= value && value <= l->last_case) {
9609                                 found = true;
9610                                 break;
9611                         }
9612                 }
9613                 if (! found) {
9614                         warningf(&statement->base.source_position,
9615                                  "enumeration value '%Y' not handled in switch",
9616                                  entry->base.symbol);
9617                 }
9618                 last_value = value;
9619         }
9620 }
9621
9622 /**
9623  * Parse a switch statement.
9624  */
9625 static statement_t *parse_switch(void)
9626 {
9627         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
9628
9629         eat(T_switch);
9630
9631         PUSH_PARENT(statement);
9632
9633         expect('(', end_error);
9634         add_anchor_token(')');
9635         expression_t *const expr = parse_expression();
9636         mark_vars_read(expr, NULL);
9637         type_t       *      type = skip_typeref(expr->base.type);
9638         if (is_type_integer(type)) {
9639                 type = promote_integer(type);
9640                 if (warning.traditional) {
9641                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
9642                                 warningf(&expr->base.source_position,
9643                                         "'%T' switch expression not converted to '%T' in ISO C",
9644                                         type, type_int);
9645                         }
9646                 }
9647         } else if (is_type_valid(type)) {
9648                 errorf(&expr->base.source_position,
9649                        "switch quantity is not an integer, but '%T'", type);
9650                 type = type_error_type;
9651         }
9652         statement->switchs.expression = create_implicit_cast(expr, type);
9653         expect(')', end_error);
9654         rem_anchor_token(')');
9655
9656         switch_statement_t *rem = current_switch;
9657         current_switch          = &statement->switchs;
9658         statement->switchs.body = parse_statement();
9659         current_switch          = rem;
9660
9661         if (warning.switch_default &&
9662             statement->switchs.default_label == NULL) {
9663                 warningf(&statement->base.source_position, "switch has no default case");
9664         }
9665         if (warning.switch_enum)
9666                 check_enum_cases(&statement->switchs);
9667
9668         POP_PARENT;
9669         return statement;
9670 end_error:
9671         POP_PARENT;
9672         return create_invalid_statement();
9673 }
9674
9675 static statement_t *parse_loop_body(statement_t *const loop)
9676 {
9677         statement_t *const rem = current_loop;
9678         current_loop = loop;
9679
9680         statement_t *const body = parse_statement();
9681
9682         current_loop = rem;
9683         return body;
9684 }
9685
9686 /**
9687  * Parse a while statement.
9688  */
9689 static statement_t *parse_while(void)
9690 {
9691         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
9692
9693         eat(T_while);
9694
9695         PUSH_PARENT(statement);
9696
9697         expect('(', end_error);
9698         add_anchor_token(')');
9699         expression_t *const cond = parse_expression();
9700         statement->whiles.condition = cond;
9701         /* §6.8.5:2    The controlling expression of an iteration statement shall
9702          *             have scalar type. */
9703         semantic_condition(cond, "condition of 'while'-statement");
9704         mark_vars_read(cond, NULL);
9705         rem_anchor_token(')');
9706         expect(')', end_error);
9707
9708         statement->whiles.body = parse_loop_body(statement);
9709
9710         POP_PARENT;
9711         return statement;
9712 end_error:
9713         POP_PARENT;
9714         return create_invalid_statement();
9715 }
9716
9717 /**
9718  * Parse a do statement.
9719  */
9720 static statement_t *parse_do(void)
9721 {
9722         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
9723
9724         eat(T_do);
9725
9726         PUSH_PARENT(statement);
9727
9728         add_anchor_token(T_while);
9729         statement->do_while.body = parse_loop_body(statement);
9730         rem_anchor_token(T_while);
9731
9732         expect(T_while, end_error);
9733         expect('(', end_error);
9734         add_anchor_token(')');
9735         expression_t *const cond = parse_expression();
9736         statement->do_while.condition = cond;
9737         /* §6.8.5:2    The controlling expression of an iteration statement shall
9738          *             have scalar type. */
9739         semantic_condition(cond, "condition of 'do-while'-statement");
9740         mark_vars_read(cond, NULL);
9741         rem_anchor_token(')');
9742         expect(')', end_error);
9743         expect(';', end_error);
9744
9745         POP_PARENT;
9746         return statement;
9747 end_error:
9748         POP_PARENT;
9749         return create_invalid_statement();
9750 }
9751
9752 /**
9753  * Parse a for statement.
9754  */
9755 static statement_t *parse_for(void)
9756 {
9757         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
9758
9759         eat(T_for);
9760
9761         expect('(', end_error1);
9762         add_anchor_token(')');
9763
9764         PUSH_PARENT(statement);
9765
9766         size_t const  top       = environment_top();
9767         scope_t      *old_scope = scope_push(&statement->fors.scope);
9768
9769         bool old_gcc_extension = in_gcc_extension;
9770         while (next_if(T___extension__)) {
9771                 in_gcc_extension = true;
9772         }
9773
9774         if (next_if(';')) {
9775         } else if (is_declaration_specifier(&token, false)) {
9776                 parse_declaration(record_entity, DECL_FLAGS_NONE);
9777         } else {
9778                 add_anchor_token(';');
9779                 expression_t *const init = parse_expression();
9780                 statement->fors.initialisation = init;
9781                 mark_vars_read(init, ENT_ANY);
9782                 if (warning.unused_value && !expression_has_effect(init)) {
9783                         warningf(&init->base.source_position,
9784                                         "initialisation of 'for'-statement has no effect");
9785                 }
9786                 rem_anchor_token(';');
9787                 expect(';', end_error2);
9788         }
9789         in_gcc_extension = old_gcc_extension;
9790
9791         if (token.type != ';') {
9792                 add_anchor_token(';');
9793                 expression_t *const cond = parse_expression();
9794                 statement->fors.condition = cond;
9795                 /* §6.8.5:2    The controlling expression of an iteration statement
9796                  *             shall have scalar type. */
9797                 semantic_condition(cond, "condition of 'for'-statement");
9798                 mark_vars_read(cond, NULL);
9799                 rem_anchor_token(';');
9800         }
9801         expect(';', end_error2);
9802         if (token.type != ')') {
9803                 expression_t *const step = parse_expression();
9804                 statement->fors.step = step;
9805                 mark_vars_read(step, ENT_ANY);
9806                 if (warning.unused_value && !expression_has_effect(step)) {
9807                         warningf(&step->base.source_position,
9808                                  "step of 'for'-statement has no effect");
9809                 }
9810         }
9811         expect(')', end_error2);
9812         rem_anchor_token(')');
9813         statement->fors.body = parse_loop_body(statement);
9814
9815         assert(current_scope == &statement->fors.scope);
9816         scope_pop(old_scope);
9817         environment_pop_to(top);
9818
9819         POP_PARENT;
9820         return statement;
9821
9822 end_error2:
9823         POP_PARENT;
9824         rem_anchor_token(')');
9825         assert(current_scope == &statement->fors.scope);
9826         scope_pop(old_scope);
9827         environment_pop_to(top);
9828         /* fallthrough */
9829
9830 end_error1:
9831         return create_invalid_statement();
9832 }
9833
9834 /**
9835  * Parse a goto statement.
9836  */
9837 static statement_t *parse_goto(void)
9838 {
9839         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
9840         eat(T_goto);
9841
9842         if (GNU_MODE && next_if('*')) {
9843                 expression_t *expression = parse_expression();
9844                 mark_vars_read(expression, NULL);
9845
9846                 /* Argh: although documentation says the expression must be of type void*,
9847                  * gcc accepts anything that can be casted into void* without error */
9848                 type_t *type = expression->base.type;
9849
9850                 if (type != type_error_type) {
9851                         if (!is_type_pointer(type) && !is_type_integer(type)) {
9852                                 errorf(&expression->base.source_position,
9853                                         "cannot convert to a pointer type");
9854                         } else if (warning.other && type != type_void_ptr) {
9855                                 warningf(&expression->base.source_position,
9856                                         "type of computed goto expression should be 'void*' not '%T'", type);
9857                         }
9858                         expression = create_implicit_cast(expression, type_void_ptr);
9859                 }
9860
9861                 statement->gotos.expression = expression;
9862         } else if (token.type == T_IDENTIFIER) {
9863                 symbol_t *symbol = token.symbol;
9864                 next_token();
9865                 statement->gotos.label = get_label(symbol);
9866         } else {
9867                 if (GNU_MODE)
9868                         parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
9869                 else
9870                         parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
9871                 eat_until_anchor();
9872                 return create_invalid_statement();
9873         }
9874
9875         /* remember the goto's in a list for later checking */
9876         *goto_anchor = &statement->gotos;
9877         goto_anchor  = &statement->gotos.next;
9878
9879         expect(';', end_error);
9880
9881 end_error:
9882         return statement;
9883 }
9884
9885 /**
9886  * Parse a continue statement.
9887  */
9888 static statement_t *parse_continue(void)
9889 {
9890         if (current_loop == NULL) {
9891                 errorf(HERE, "continue statement not within loop");
9892         }
9893
9894         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
9895
9896         eat(T_continue);
9897         expect(';', end_error);
9898
9899 end_error:
9900         return statement;
9901 }
9902
9903 /**
9904  * Parse a break statement.
9905  */
9906 static statement_t *parse_break(void)
9907 {
9908         if (current_switch == NULL && current_loop == NULL) {
9909                 errorf(HERE, "break statement not within loop or switch");
9910         }
9911
9912         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
9913
9914         eat(T_break);
9915         expect(';', end_error);
9916
9917 end_error:
9918         return statement;
9919 }
9920
9921 /**
9922  * Parse a __leave statement.
9923  */
9924 static statement_t *parse_leave_statement(void)
9925 {
9926         if (current_try == NULL) {
9927                 errorf(HERE, "__leave statement not within __try");
9928         }
9929
9930         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
9931
9932         eat(T___leave);
9933         expect(';', end_error);
9934
9935 end_error:
9936         return statement;
9937 }
9938
9939 /**
9940  * Check if a given entity represents a local variable.
9941  */
9942 static bool is_local_variable(const entity_t *entity)
9943 {
9944         if (entity->kind != ENTITY_VARIABLE)
9945                 return false;
9946
9947         switch ((storage_class_tag_t) entity->declaration.storage_class) {
9948         case STORAGE_CLASS_AUTO:
9949         case STORAGE_CLASS_REGISTER: {
9950                 const type_t *type = skip_typeref(entity->declaration.type);
9951                 if (is_type_function(type)) {
9952                         return false;
9953                 } else {
9954                         return true;
9955                 }
9956         }
9957         default:
9958                 return false;
9959         }
9960 }
9961
9962 /**
9963  * Check if a given expression represents a local variable.
9964  */
9965 static bool expression_is_local_variable(const expression_t *expression)
9966 {
9967         if (expression->base.kind != EXPR_REFERENCE) {
9968                 return false;
9969         }
9970         const entity_t *entity = expression->reference.entity;
9971         return is_local_variable(entity);
9972 }
9973
9974 /**
9975  * Check if a given expression represents a local variable and
9976  * return its declaration then, else return NULL.
9977  */
9978 entity_t *expression_is_variable(const expression_t *expression)
9979 {
9980         if (expression->base.kind != EXPR_REFERENCE) {
9981                 return NULL;
9982         }
9983         entity_t *entity = expression->reference.entity;
9984         if (entity->kind != ENTITY_VARIABLE)
9985                 return NULL;
9986
9987         return entity;
9988 }
9989
9990 /**
9991  * Parse a return statement.
9992  */
9993 static statement_t *parse_return(void)
9994 {
9995         eat(T_return);
9996
9997         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
9998
9999         expression_t *return_value = NULL;
10000         if (token.type != ';') {
10001                 return_value = parse_expression();
10002                 mark_vars_read(return_value, NULL);
10003         }
10004
10005         const type_t *const func_type = skip_typeref(current_function->base.type);
10006         assert(is_type_function(func_type));
10007         type_t *const return_type = skip_typeref(func_type->function.return_type);
10008
10009         source_position_t const *const pos = &statement->base.source_position;
10010         if (return_value != NULL) {
10011                 type_t *return_value_type = skip_typeref(return_value->base.type);
10012
10013                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10014                         if (is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
10015                                 /* ISO/IEC 14882:1998(E) §6.6.3:2 */
10016                                 /* Only warn in C mode, because GCC does the same */
10017                                 if (c_mode & _CXX || strict_mode) {
10018                                         errorf(pos,
10019                                                         "'return' with a value, in function returning 'void'");
10020                                 } else if (warning.other) {
10021                                         warningf(pos,
10022                                                         "'return' with a value, in function returning 'void'");
10023                                 }
10024                         } else if (!(c_mode & _CXX)) { /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10025                                 /* Only warn in C mode, because GCC does the same */
10026                                 if (strict_mode) {
10027                                         errorf(pos,
10028                                                         "'return' with expression in function returning 'void'");
10029                                 } else if (warning.other) {
10030                                         warningf(pos,
10031                                                         "'return' with expression in function returning 'void'");
10032                                 }
10033                         }
10034                 } else {
10035                         assign_error_t error = semantic_assign(return_type, return_value);
10036                         report_assign_error(error, return_type, return_value, "'return'",
10037                                             pos);
10038                 }
10039                 return_value = create_implicit_cast(return_value, return_type);
10040                 /* check for returning address of a local var */
10041                 if (warning.other && return_value != NULL
10042                     && return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
10043                         const expression_t *expression = return_value->unary.value;
10044                         if (expression_is_local_variable(expression)) {
10045                                 warningf(pos, "function returns address of local variable");
10046                         }
10047                 }
10048         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
10049                 /* ISO/IEC 14882:1998(E) §6.6.3:3 */
10050                 if (c_mode & _CXX || strict_mode) {
10051                         errorf(pos,
10052                                "'return' without value, in function returning non-void");
10053                 } else {
10054                         warningf(pos,
10055                                  "'return' without value, in function returning non-void");
10056                 }
10057         }
10058         statement->returns.value = return_value;
10059
10060         expect(';', end_error);
10061
10062 end_error:
10063         return statement;
10064 }
10065
10066 /**
10067  * Parse a declaration statement.
10068  */
10069 static statement_t *parse_declaration_statement(void)
10070 {
10071         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10072
10073         entity_t *before = current_scope->last_entity;
10074         if (GNU_MODE) {
10075                 parse_external_declaration();
10076         } else {
10077                 parse_declaration(record_entity, DECL_FLAGS_NONE);
10078         }
10079
10080         declaration_statement_t *const decl  = &statement->declaration;
10081         entity_t                *const begin =
10082                 before != NULL ? before->base.next : current_scope->entities;
10083         decl->declarations_begin = begin;
10084         decl->declarations_end   = begin != NULL ? current_scope->last_entity : NULL;
10085
10086         return statement;
10087 }
10088
10089 /**
10090  * Parse an expression statement, ie. expr ';'.
10091  */
10092 static statement_t *parse_expression_statement(void)
10093 {
10094         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10095
10096         expression_t *const expr         = parse_expression();
10097         statement->expression.expression = expr;
10098         mark_vars_read(expr, ENT_ANY);
10099
10100         expect(';', end_error);
10101
10102 end_error:
10103         return statement;
10104 }
10105
10106 /**
10107  * Parse a microsoft __try { } __finally { } or
10108  * __try{ } __except() { }
10109  */
10110 static statement_t *parse_ms_try_statment(void)
10111 {
10112         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
10113         eat(T___try);
10114
10115         PUSH_PARENT(statement);
10116
10117         ms_try_statement_t *rem = current_try;
10118         current_try = &statement->ms_try;
10119         statement->ms_try.try_statement = parse_compound_statement(false);
10120         current_try = rem;
10121
10122         POP_PARENT;
10123
10124         if (next_if(T___except)) {
10125                 expect('(', end_error);
10126                 add_anchor_token(')');
10127                 expression_t *const expr = parse_expression();
10128                 mark_vars_read(expr, NULL);
10129                 type_t       *      type = skip_typeref(expr->base.type);
10130                 if (is_type_integer(type)) {
10131                         type = promote_integer(type);
10132                 } else if (is_type_valid(type)) {
10133                         errorf(&expr->base.source_position,
10134                                "__expect expression is not an integer, but '%T'", type);
10135                         type = type_error_type;
10136                 }
10137                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
10138                 rem_anchor_token(')');
10139                 expect(')', end_error);
10140                 statement->ms_try.final_statement = parse_compound_statement(false);
10141         } else if (next_if(T__finally)) {
10142                 statement->ms_try.final_statement = parse_compound_statement(false);
10143         } else {
10144                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
10145                 return create_invalid_statement();
10146         }
10147         return statement;
10148 end_error:
10149         return create_invalid_statement();
10150 }
10151
10152 static statement_t *parse_empty_statement(void)
10153 {
10154         if (warning.empty_statement) {
10155                 warningf(HERE, "statement is empty");
10156         }
10157         statement_t *const statement = create_empty_statement();
10158         eat(';');
10159         return statement;
10160 }
10161
10162 static statement_t *parse_local_label_declaration(void)
10163 {
10164         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10165
10166         eat(T___label__);
10167
10168         entity_t *begin   = NULL;
10169         entity_t *end     = NULL;
10170         entity_t **anchor = &begin;
10171         do {
10172                 if (token.type != T_IDENTIFIER) {
10173                         parse_error_expected("while parsing local label declaration",
10174                                 T_IDENTIFIER, NULL);
10175                         goto end_error;
10176                 }
10177                 symbol_t *symbol = token.symbol;
10178                 entity_t *entity = get_entity(symbol, NAMESPACE_LABEL);
10179                 if (entity != NULL && entity->base.parent_scope == current_scope) {
10180                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition %P)",
10181                                symbol, &entity->base.source_position);
10182                 } else {
10183                         entity = allocate_entity_zero(ENTITY_LOCAL_LABEL);
10184
10185                         entity->base.parent_scope    = current_scope;
10186                         entity->base.namespc         = NAMESPACE_LABEL;
10187                         entity->base.source_position = token.source_position;
10188                         entity->base.symbol          = symbol;
10189
10190                         *anchor = entity;
10191                         anchor  = &entity->base.next;
10192                         end     = entity;
10193
10194                         environment_push(entity);
10195                 }
10196                 next_token();
10197         } while (next_if(','));
10198         expect(';', end_error);
10199 end_error:
10200         statement->declaration.declarations_begin = begin;
10201         statement->declaration.declarations_end   = end;
10202         return statement;
10203 }
10204
10205 static void parse_namespace_definition(void)
10206 {
10207         eat(T_namespace);
10208
10209         entity_t *entity = NULL;
10210         symbol_t *symbol = NULL;
10211
10212         if (token.type == T_IDENTIFIER) {
10213                 symbol = token.symbol;
10214                 next_token();
10215
10216                 entity = get_entity(symbol, NAMESPACE_NORMAL);
10217                 if (entity != NULL
10218                                 && entity->kind != ENTITY_NAMESPACE
10219                                 && entity->base.parent_scope == current_scope) {
10220                         if (is_entity_valid(entity)) {
10221                                 error_redefined_as_different_kind(&token.source_position,
10222                                                 entity, ENTITY_NAMESPACE);
10223                         }
10224                         entity = NULL;
10225                 }
10226         }
10227
10228         if (entity == NULL) {
10229                 entity                       = allocate_entity_zero(ENTITY_NAMESPACE);
10230                 entity->base.symbol          = symbol;
10231                 entity->base.source_position = token.source_position;
10232                 entity->base.namespc         = NAMESPACE_NORMAL;
10233                 entity->base.parent_scope    = current_scope;
10234         }
10235
10236         if (token.type == '=') {
10237                 /* TODO: parse namespace alias */
10238                 panic("namespace alias definition not supported yet");
10239         }
10240
10241         environment_push(entity);
10242         append_entity(current_scope, entity);
10243
10244         size_t const  top       = environment_top();
10245         scope_t      *old_scope = scope_push(&entity->namespacee.members);
10246
10247         entity_t     *old_current_entity = current_entity;
10248         current_entity = entity;
10249
10250         expect('{', end_error);
10251         parse_externals();
10252         expect('}', end_error);
10253
10254 end_error:
10255         assert(current_scope == &entity->namespacee.members);
10256         assert(current_entity == entity);
10257         current_entity = old_current_entity;
10258         scope_pop(old_scope);
10259         environment_pop_to(top);
10260 }
10261
10262 /**
10263  * Parse a statement.
10264  * There's also parse_statement() which additionally checks for
10265  * "statement has no effect" warnings
10266  */
10267 static statement_t *intern_parse_statement(void)
10268 {
10269         statement_t *statement = NULL;
10270
10271         /* declaration or statement */
10272         add_anchor_token(';');
10273         switch (token.type) {
10274         case T_IDENTIFIER: {
10275                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
10276                 if (la1_type == ':') {
10277                         statement = parse_label_statement();
10278                 } else if (is_typedef_symbol(token.symbol)) {
10279                         statement = parse_declaration_statement();
10280                 } else {
10281                         /* it's an identifier, the grammar says this must be an
10282                          * expression statement. However it is common that users mistype
10283                          * declaration types, so we guess a bit here to improve robustness
10284                          * for incorrect programs */
10285                         switch (la1_type) {
10286                         case '&':
10287                         case '*':
10288                                 if (get_entity(token.symbol, NAMESPACE_NORMAL) != NULL) {
10289                         default:
10290                                         statement = parse_expression_statement();
10291                                 } else {
10292                         DECLARATION_START
10293                         case T_IDENTIFIER:
10294                                         statement = parse_declaration_statement();
10295                                 }
10296                                 break;
10297                         }
10298                 }
10299                 break;
10300         }
10301
10302         case T___extension__:
10303                 /* This can be a prefix to a declaration or an expression statement.
10304                  * We simply eat it now and parse the rest with tail recursion. */
10305                 while (next_if(T___extension__)) {}
10306                 bool old_gcc_extension = in_gcc_extension;
10307                 in_gcc_extension       = true;
10308                 statement = intern_parse_statement();
10309                 in_gcc_extension = old_gcc_extension;
10310                 break;
10311
10312         DECLARATION_START
10313                 statement = parse_declaration_statement();
10314                 break;
10315
10316         case T___label__:
10317                 statement = parse_local_label_declaration();
10318                 break;
10319
10320         case ';':         statement = parse_empty_statement();         break;
10321         case '{':         statement = parse_compound_statement(false); break;
10322         case T___leave:   statement = parse_leave_statement();         break;
10323         case T___try:     statement = parse_ms_try_statment();         break;
10324         case T_asm:       statement = parse_asm_statement();           break;
10325         case T_break:     statement = parse_break();                   break;
10326         case T_case:      statement = parse_case_statement();          break;
10327         case T_continue:  statement = parse_continue();                break;
10328         case T_default:   statement = parse_default_statement();       break;
10329         case T_do:        statement = parse_do();                      break;
10330         case T_for:       statement = parse_for();                     break;
10331         case T_goto:      statement = parse_goto();                    break;
10332         case T_if:        statement = parse_if();                      break;
10333         case T_return:    statement = parse_return();                  break;
10334         case T_switch:    statement = parse_switch();                  break;
10335         case T_while:     statement = parse_while();                   break;
10336
10337         EXPRESSION_START
10338                 statement = parse_expression_statement();
10339                 break;
10340
10341         default:
10342                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10343                 statement = create_invalid_statement();
10344                 if (!at_anchor())
10345                         next_token();
10346                 break;
10347         }
10348         rem_anchor_token(';');
10349
10350         assert(statement != NULL
10351                         && statement->base.source_position.input_name != NULL);
10352
10353         return statement;
10354 }
10355
10356 /**
10357  * parse a statement and emits "statement has no effect" warning if needed
10358  * (This is really a wrapper around intern_parse_statement with check for 1
10359  *  single warning. It is needed, because for statement expressions we have
10360  *  to avoid the warning on the last statement)
10361  */
10362 static statement_t *parse_statement(void)
10363 {
10364         statement_t *statement = intern_parse_statement();
10365
10366         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10367                 expression_t *expression = statement->expression.expression;
10368                 if (!expression_has_effect(expression)) {
10369                         warningf(&expression->base.source_position,
10370                                         "statement has no effect");
10371                 }
10372         }
10373
10374         return statement;
10375 }
10376
10377 /**
10378  * Parse a compound statement.
10379  */
10380 static statement_t *parse_compound_statement(bool inside_expression_statement)
10381 {
10382         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10383
10384         PUSH_PARENT(statement);
10385
10386         eat('{');
10387         add_anchor_token('}');
10388         /* tokens, which can start a statement */
10389         /* TODO MS, __builtin_FOO */
10390         add_anchor_token('!');
10391         add_anchor_token('&');
10392         add_anchor_token('(');
10393         add_anchor_token('*');
10394         add_anchor_token('+');
10395         add_anchor_token('-');
10396         add_anchor_token('{');
10397         add_anchor_token('~');
10398         add_anchor_token(T_CHARACTER_CONSTANT);
10399         add_anchor_token(T_COLONCOLON);
10400         add_anchor_token(T_FLOATINGPOINT);
10401         add_anchor_token(T_IDENTIFIER);
10402         add_anchor_token(T_INTEGER);
10403         add_anchor_token(T_MINUSMINUS);
10404         add_anchor_token(T_PLUSPLUS);
10405         add_anchor_token(T_STRING_LITERAL);
10406         add_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10407         add_anchor_token(T_WIDE_STRING_LITERAL);
10408         add_anchor_token(T__Bool);
10409         add_anchor_token(T__Complex);
10410         add_anchor_token(T__Imaginary);
10411         add_anchor_token(T___FUNCTION__);
10412         add_anchor_token(T___PRETTY_FUNCTION__);
10413         add_anchor_token(T___alignof__);
10414         add_anchor_token(T___attribute__);
10415         add_anchor_token(T___builtin_va_start);
10416         add_anchor_token(T___extension__);
10417         add_anchor_token(T___func__);
10418         add_anchor_token(T___imag__);
10419         add_anchor_token(T___label__);
10420         add_anchor_token(T___real__);
10421         add_anchor_token(T___thread);
10422         add_anchor_token(T_asm);
10423         add_anchor_token(T_auto);
10424         add_anchor_token(T_bool);
10425         add_anchor_token(T_break);
10426         add_anchor_token(T_case);
10427         add_anchor_token(T_char);
10428         add_anchor_token(T_class);
10429         add_anchor_token(T_const);
10430         add_anchor_token(T_const_cast);
10431         add_anchor_token(T_continue);
10432         add_anchor_token(T_default);
10433         add_anchor_token(T_delete);
10434         add_anchor_token(T_double);
10435         add_anchor_token(T_do);
10436         add_anchor_token(T_dynamic_cast);
10437         add_anchor_token(T_enum);
10438         add_anchor_token(T_extern);
10439         add_anchor_token(T_false);
10440         add_anchor_token(T_float);
10441         add_anchor_token(T_for);
10442         add_anchor_token(T_goto);
10443         add_anchor_token(T_if);
10444         add_anchor_token(T_inline);
10445         add_anchor_token(T_int);
10446         add_anchor_token(T_long);
10447         add_anchor_token(T_new);
10448         add_anchor_token(T_operator);
10449         add_anchor_token(T_register);
10450         add_anchor_token(T_reinterpret_cast);
10451         add_anchor_token(T_restrict);
10452         add_anchor_token(T_return);
10453         add_anchor_token(T_short);
10454         add_anchor_token(T_signed);
10455         add_anchor_token(T_sizeof);
10456         add_anchor_token(T_static);
10457         add_anchor_token(T_static_cast);
10458         add_anchor_token(T_struct);
10459         add_anchor_token(T_switch);
10460         add_anchor_token(T_template);
10461         add_anchor_token(T_this);
10462         add_anchor_token(T_throw);
10463         add_anchor_token(T_true);
10464         add_anchor_token(T_try);
10465         add_anchor_token(T_typedef);
10466         add_anchor_token(T_typeid);
10467         add_anchor_token(T_typename);
10468         add_anchor_token(T_typeof);
10469         add_anchor_token(T_union);
10470         add_anchor_token(T_unsigned);
10471         add_anchor_token(T_using);
10472         add_anchor_token(T_void);
10473         add_anchor_token(T_volatile);
10474         add_anchor_token(T_wchar_t);
10475         add_anchor_token(T_while);
10476
10477         size_t const  top       = environment_top();
10478         scope_t      *old_scope = scope_push(&statement->compound.scope);
10479
10480         statement_t **anchor            = &statement->compound.statements;
10481         bool          only_decls_so_far = true;
10482         while (token.type != '}') {
10483                 if (token.type == T_EOF) {
10484                         errorf(&statement->base.source_position,
10485                                "EOF while parsing compound statement");
10486                         break;
10487                 }
10488                 statement_t *sub_statement = intern_parse_statement();
10489                 if (is_invalid_statement(sub_statement)) {
10490                         /* an error occurred. if we are at an anchor, return */
10491                         if (at_anchor())
10492                                 goto end_error;
10493                         continue;
10494                 }
10495
10496                 if (warning.declaration_after_statement) {
10497                         if (sub_statement->kind != STATEMENT_DECLARATION) {
10498                                 only_decls_so_far = false;
10499                         } else if (!only_decls_so_far) {
10500                                 warningf(&sub_statement->base.source_position,
10501                                          "ISO C90 forbids mixed declarations and code");
10502                         }
10503                 }
10504
10505                 *anchor = sub_statement;
10506
10507                 while (sub_statement->base.next != NULL)
10508                         sub_statement = sub_statement->base.next;
10509
10510                 anchor = &sub_statement->base.next;
10511         }
10512         next_token();
10513
10514         /* look over all statements again to produce no effect warnings */
10515         if (warning.unused_value) {
10516                 statement_t *sub_statement = statement->compound.statements;
10517                 for (; sub_statement != NULL; sub_statement = sub_statement->base.next) {
10518                         if (sub_statement->kind != STATEMENT_EXPRESSION)
10519                                 continue;
10520                         /* don't emit a warning for the last expression in an expression
10521                          * statement as it has always an effect */
10522                         if (inside_expression_statement && sub_statement->base.next == NULL)
10523                                 continue;
10524
10525                         expression_t *expression = sub_statement->expression.expression;
10526                         if (!expression_has_effect(expression)) {
10527                                 warningf(&expression->base.source_position,
10528                                          "statement has no effect");
10529                         }
10530                 }
10531         }
10532
10533 end_error:
10534         rem_anchor_token(T_while);
10535         rem_anchor_token(T_wchar_t);
10536         rem_anchor_token(T_volatile);
10537         rem_anchor_token(T_void);
10538         rem_anchor_token(T_using);
10539         rem_anchor_token(T_unsigned);
10540         rem_anchor_token(T_union);
10541         rem_anchor_token(T_typeof);
10542         rem_anchor_token(T_typename);
10543         rem_anchor_token(T_typeid);
10544         rem_anchor_token(T_typedef);
10545         rem_anchor_token(T_try);
10546         rem_anchor_token(T_true);
10547         rem_anchor_token(T_throw);
10548         rem_anchor_token(T_this);
10549         rem_anchor_token(T_template);
10550         rem_anchor_token(T_switch);
10551         rem_anchor_token(T_struct);
10552         rem_anchor_token(T_static_cast);
10553         rem_anchor_token(T_static);
10554         rem_anchor_token(T_sizeof);
10555         rem_anchor_token(T_signed);
10556         rem_anchor_token(T_short);
10557         rem_anchor_token(T_return);
10558         rem_anchor_token(T_restrict);
10559         rem_anchor_token(T_reinterpret_cast);
10560         rem_anchor_token(T_register);
10561         rem_anchor_token(T_operator);
10562         rem_anchor_token(T_new);
10563         rem_anchor_token(T_long);
10564         rem_anchor_token(T_int);
10565         rem_anchor_token(T_inline);
10566         rem_anchor_token(T_if);
10567         rem_anchor_token(T_goto);
10568         rem_anchor_token(T_for);
10569         rem_anchor_token(T_float);
10570         rem_anchor_token(T_false);
10571         rem_anchor_token(T_extern);
10572         rem_anchor_token(T_enum);
10573         rem_anchor_token(T_dynamic_cast);
10574         rem_anchor_token(T_do);
10575         rem_anchor_token(T_double);
10576         rem_anchor_token(T_delete);
10577         rem_anchor_token(T_default);
10578         rem_anchor_token(T_continue);
10579         rem_anchor_token(T_const_cast);
10580         rem_anchor_token(T_const);
10581         rem_anchor_token(T_class);
10582         rem_anchor_token(T_char);
10583         rem_anchor_token(T_case);
10584         rem_anchor_token(T_break);
10585         rem_anchor_token(T_bool);
10586         rem_anchor_token(T_auto);
10587         rem_anchor_token(T_asm);
10588         rem_anchor_token(T___thread);
10589         rem_anchor_token(T___real__);
10590         rem_anchor_token(T___label__);
10591         rem_anchor_token(T___imag__);
10592         rem_anchor_token(T___func__);
10593         rem_anchor_token(T___extension__);
10594         rem_anchor_token(T___builtin_va_start);
10595         rem_anchor_token(T___attribute__);
10596         rem_anchor_token(T___alignof__);
10597         rem_anchor_token(T___PRETTY_FUNCTION__);
10598         rem_anchor_token(T___FUNCTION__);
10599         rem_anchor_token(T__Imaginary);
10600         rem_anchor_token(T__Complex);
10601         rem_anchor_token(T__Bool);
10602         rem_anchor_token(T_WIDE_STRING_LITERAL);
10603         rem_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10604         rem_anchor_token(T_STRING_LITERAL);
10605         rem_anchor_token(T_PLUSPLUS);
10606         rem_anchor_token(T_MINUSMINUS);
10607         rem_anchor_token(T_INTEGER);
10608         rem_anchor_token(T_IDENTIFIER);
10609         rem_anchor_token(T_FLOATINGPOINT);
10610         rem_anchor_token(T_COLONCOLON);
10611         rem_anchor_token(T_CHARACTER_CONSTANT);
10612         rem_anchor_token('~');
10613         rem_anchor_token('{');
10614         rem_anchor_token('-');
10615         rem_anchor_token('+');
10616         rem_anchor_token('*');
10617         rem_anchor_token('(');
10618         rem_anchor_token('&');
10619         rem_anchor_token('!');
10620         rem_anchor_token('}');
10621         assert(current_scope == &statement->compound.scope);
10622         scope_pop(old_scope);
10623         environment_pop_to(top);
10624
10625         POP_PARENT;
10626         return statement;
10627 }
10628
10629 /**
10630  * Check for unused global static functions and variables
10631  */
10632 static void check_unused_globals(void)
10633 {
10634         if (!warning.unused_function && !warning.unused_variable)
10635                 return;
10636
10637         for (const entity_t *entity = file_scope->entities; entity != NULL;
10638              entity = entity->base.next) {
10639                 if (!is_declaration(entity))
10640                         continue;
10641
10642                 const declaration_t *declaration = &entity->declaration;
10643                 if (declaration->used                  ||
10644                     declaration->modifiers & DM_UNUSED ||
10645                     declaration->modifiers & DM_USED   ||
10646                     declaration->storage_class != STORAGE_CLASS_STATIC)
10647                         continue;
10648
10649                 type_t *const type = declaration->type;
10650                 const char *s;
10651                 if (entity->kind == ENTITY_FUNCTION) {
10652                         /* inhibit warning for static inline functions */
10653                         if (entity->function.is_inline)
10654                                 continue;
10655
10656                         s = entity->function.statement != NULL ? "defined" : "declared";
10657                 } else {
10658                         s = "defined";
10659                 }
10660
10661                 warningf(&declaration->base.source_position, "'%#T' %s but not used",
10662                         type, declaration->base.symbol, s);
10663         }
10664 }
10665
10666 static void parse_global_asm(void)
10667 {
10668         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
10669
10670         eat(T_asm);
10671         expect('(', end_error);
10672
10673         statement->asms.asm_text = parse_string_literals();
10674         statement->base.next     = unit->global_asm;
10675         unit->global_asm         = statement;
10676
10677         expect(')', end_error);
10678         expect(';', end_error);
10679
10680 end_error:;
10681 }
10682
10683 static void parse_linkage_specification(void)
10684 {
10685         eat(T_extern);
10686
10687         const char *linkage = parse_string_literals().begin;
10688
10689         linkage_kind_t old_linkage = current_linkage;
10690         linkage_kind_t new_linkage;
10691         if (strcmp(linkage, "C") == 0) {
10692                 new_linkage = LINKAGE_C;
10693         } else if (strcmp(linkage, "C++") == 0) {
10694                 new_linkage = LINKAGE_CXX;
10695         } else {
10696                 errorf(HERE, "linkage string \"%s\" not recognized", linkage);
10697                 new_linkage = LINKAGE_INVALID;
10698         }
10699         current_linkage = new_linkage;
10700
10701         if (next_if('{')) {
10702                 parse_externals();
10703                 expect('}', end_error);
10704         } else {
10705                 parse_external();
10706         }
10707
10708 end_error:
10709         assert(current_linkage == new_linkage);
10710         current_linkage = old_linkage;
10711 }
10712
10713 static void parse_external(void)
10714 {
10715         switch (token.type) {
10716                 DECLARATION_START_NO_EXTERN
10717                 case T_IDENTIFIER:
10718                 case T___extension__:
10719                 /* tokens below are for implicit int */
10720                 case '&': /* & x; -> int& x; (and error later, because C++ has no
10721                              implicit int) */
10722                 case '*': /* * x; -> int* x; */
10723                 case '(': /* (x); -> int (x); */
10724                         parse_external_declaration();
10725                         return;
10726
10727                 case T_extern:
10728                         if (look_ahead(1)->type == T_STRING_LITERAL) {
10729                                 parse_linkage_specification();
10730                         } else {
10731                                 parse_external_declaration();
10732                         }
10733                         return;
10734
10735                 case T_asm:
10736                         parse_global_asm();
10737                         return;
10738
10739                 case T_namespace:
10740                         parse_namespace_definition();
10741                         return;
10742
10743                 case ';':
10744                         if (!strict_mode) {
10745                                 if (warning.other)
10746                                         warningf(HERE, "stray ';' outside of function");
10747                                 next_token();
10748                                 return;
10749                         }
10750                         /* FALLTHROUGH */
10751
10752                 default:
10753                         errorf(HERE, "stray %K outside of function", &token);
10754                         if (token.type == '(' || token.type == '{' || token.type == '[')
10755                                 eat_until_matching_token(token.type);
10756                         next_token();
10757                         return;
10758         }
10759 }
10760
10761 static void parse_externals(void)
10762 {
10763         add_anchor_token('}');
10764         add_anchor_token(T_EOF);
10765
10766 #ifndef NDEBUG
10767         /* make a copy of the anchor set, so we can check if it is restored after parsing */
10768         unsigned char token_anchor_copy[T_LAST_TOKEN];
10769         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
10770 #endif
10771
10772         while (token.type != T_EOF && token.type != '}') {
10773 #ifndef NDEBUG
10774                 bool anchor_leak = false;
10775                 for (int i = 0; i < T_LAST_TOKEN; ++i) {
10776                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
10777                         if (count != 0) {
10778                                 /* the anchor set and its copy differs */
10779                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
10780                                 anchor_leak = true;
10781                         }
10782                 }
10783                 if (in_gcc_extension) {
10784                         /* an gcc extension scope was not closed */
10785                         errorf(HERE, "Leaked __extension__");
10786                         anchor_leak = true;
10787                 }
10788
10789                 if (anchor_leak)
10790                         abort();
10791 #endif
10792
10793                 parse_external();
10794         }
10795
10796         rem_anchor_token(T_EOF);
10797         rem_anchor_token('}');
10798 }
10799
10800 /**
10801  * Parse a translation unit.
10802  */
10803 static void parse_translation_unit(void)
10804 {
10805         add_anchor_token(T_EOF);
10806
10807         while (true) {
10808                 parse_externals();
10809
10810                 if (token.type == T_EOF)
10811                         break;
10812
10813                 errorf(HERE, "stray %K outside of function", &token);
10814                 if (token.type == '(' || token.type == '{' || token.type == '[')
10815                         eat_until_matching_token(token.type);
10816                 next_token();
10817         }
10818 }
10819
10820 /**
10821  * Parse the input.
10822  *
10823  * @return  the translation unit or NULL if errors occurred.
10824  */
10825 void start_parsing(void)
10826 {
10827         environment_stack = NEW_ARR_F(stack_entry_t, 0);
10828         label_stack       = NEW_ARR_F(stack_entry_t, 0);
10829         diagnostic_count  = 0;
10830         error_count       = 0;
10831         warning_count     = 0;
10832
10833         print_to_file(stderr);
10834
10835         assert(unit == NULL);
10836         unit = allocate_ast_zero(sizeof(unit[0]));
10837
10838         assert(file_scope == NULL);
10839         file_scope = &unit->scope;
10840
10841         assert(current_scope == NULL);
10842         scope_push(&unit->scope);
10843
10844         create_gnu_builtins();
10845         if (c_mode & _MS)
10846                 create_microsoft_intrinsics();
10847 }
10848
10849 translation_unit_t *finish_parsing(void)
10850 {
10851         assert(current_scope == &unit->scope);
10852         scope_pop(NULL);
10853
10854         assert(file_scope == &unit->scope);
10855         check_unused_globals();
10856         file_scope = NULL;
10857
10858         DEL_ARR_F(environment_stack);
10859         DEL_ARR_F(label_stack);
10860
10861         translation_unit_t *result = unit;
10862         unit = NULL;
10863         return result;
10864 }
10865
10866 /* §6.9.2:2 and §6.9.2:5: At the end of the translation incomplete arrays
10867  * are given length one. */
10868 static void complete_incomplete_arrays(void)
10869 {
10870         size_t n = ARR_LEN(incomplete_arrays);
10871         for (size_t i = 0; i != n; ++i) {
10872                 declaration_t *const decl      = incomplete_arrays[i];
10873                 type_t        *const orig_type = decl->type;
10874                 type_t        *const type      = skip_typeref(orig_type);
10875
10876                 if (!is_type_incomplete(type))
10877                         continue;
10878
10879                 if (warning.other) {
10880                         warningf(&decl->base.source_position,
10881                                         "array '%#T' assumed to have one element",
10882                                         orig_type, decl->base.symbol);
10883                 }
10884
10885                 type_t *const new_type = duplicate_type(type);
10886                 new_type->array.size_constant     = true;
10887                 new_type->array.has_implicit_size = true;
10888                 new_type->array.size              = 1;
10889
10890                 type_t *const result = identify_new_type(new_type);
10891
10892                 decl->type = result;
10893         }
10894 }
10895
10896 void prepare_main_collect2(entity_t *entity)
10897 {
10898         // create call to __main
10899         symbol_t *symbol         = symbol_table_insert("__main");
10900         entity_t *subsubmain_ent
10901                 = create_implicit_function(symbol, &builtin_source_position);
10902
10903         expression_t *ref         = allocate_expression_zero(EXPR_REFERENCE);
10904         type_t       *ftype       = subsubmain_ent->declaration.type;
10905         ref->base.source_position = builtin_source_position;
10906         ref->base.type            = make_pointer_type(ftype, TYPE_QUALIFIER_NONE);
10907         ref->reference.entity     = subsubmain_ent;
10908
10909         expression_t *call = allocate_expression_zero(EXPR_CALL);
10910         call->base.source_position = builtin_source_position;
10911         call->base.type            = type_void;
10912         call->call.function        = ref;
10913
10914         statement_t *expr_statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10915         expr_statement->base.source_position  = builtin_source_position;
10916         expr_statement->expression.expression = call;
10917
10918         statement_t *statement = entity->function.statement;
10919         assert(statement->kind == STATEMENT_COMPOUND);
10920         compound_statement_t *compounds = &statement->compound;
10921
10922         expr_statement->base.next = compounds->statements;
10923         compounds->statements     = expr_statement;
10924 }
10925
10926 void parse(void)
10927 {
10928         lookahead_bufpos = 0;
10929         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
10930                 next_token();
10931         }
10932         current_linkage   = c_mode & _CXX ? LINKAGE_CXX : LINKAGE_C;
10933         incomplete_arrays = NEW_ARR_F(declaration_t*, 0);
10934         parse_translation_unit();
10935         complete_incomplete_arrays();
10936         DEL_ARR_F(incomplete_arrays);
10937         incomplete_arrays = NULL;
10938 }
10939
10940 /**
10941  * Initialize the parser.
10942  */
10943 void init_parser(void)
10944 {
10945         sym_anonymous = symbol_table_insert("<anonymous>");
10946
10947         memset(token_anchor_set, 0, sizeof(token_anchor_set));
10948
10949         init_expression_parsers();
10950         obstack_init(&temp_obst);
10951 }
10952
10953 /**
10954  * Terminate the parser.
10955  */
10956 void exit_parser(void)
10957 {
10958         obstack_free(&temp_obst, NULL);
10959 }