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