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 static construct_type_t *parse_pointer_declarator(void)
3491 {
3492         eat('*');
3493
3494         parsed_pointer_t *pointer = obstack_alloc(&temp_obst, sizeof(pointer[0]));
3495         memset(pointer, 0, sizeof(pointer[0]));
3496         pointer->base.kind       = CONSTRUCT_POINTER;
3497         pointer->type_qualifiers = parse_type_qualifiers();
3498         //pointer->base_variable       = base_variable;
3499
3500         return (construct_type_t*) pointer;
3501 }
3502
3503 static construct_type_t *parse_reference_declarator(void)
3504 {
3505         eat('&');
3506
3507         construct_type_t   *cons      = obstack_alloc(&temp_obst, sizeof(cons->reference));
3508         parsed_reference_t *reference = &cons->reference;
3509         memset(reference, 0, sizeof(*reference));
3510         cons->kind = CONSTRUCT_REFERENCE;
3511
3512         return cons;
3513 }
3514
3515 static construct_type_t *parse_array_declarator(void)
3516 {
3517         eat('[');
3518         add_anchor_token(']');
3519
3520         construct_type_t *cons  = obstack_alloc(&temp_obst, sizeof(cons->array));
3521         parsed_array_t   *array = &cons->array;
3522         memset(array, 0, sizeof(*array));
3523         cons->kind = CONSTRUCT_ARRAY;
3524
3525         if (next_if(T_static))
3526                 array->is_static = true;
3527
3528         type_qualifiers_t type_qualifiers = parse_type_qualifiers();
3529         if (type_qualifiers != 0 && next_if(T_static))
3530                         array->is_static = true;
3531         array->type_qualifiers = type_qualifiers;
3532
3533         if (token.type == '*' && look_ahead(1)->type == ']') {
3534                 array->is_variable = true;
3535                 next_token();
3536         } else if (token.type != ']') {
3537                 expression_t *const size = parse_assignment_expression();
3538
3539                 /* §6.7.5.2:1  Array size must have integer type */
3540                 type_t *const orig_type = size->base.type;
3541                 type_t *const type      = skip_typeref(orig_type);
3542                 if (!is_type_integer(type) && is_type_valid(type)) {
3543                         errorf(&size->base.source_position,
3544                                "array size '%E' must have integer type but has type '%T'",
3545                                size, orig_type);
3546                 }
3547
3548                 array->size = size;
3549                 mark_vars_read(size, NULL);
3550         }
3551
3552         rem_anchor_token(']');
3553         expect(']', end_error);
3554
3555 end_error:
3556         return cons;
3557 }
3558
3559 static construct_type_t *parse_function_declarator(scope_t *scope)
3560 {
3561         type_t          *type  = allocate_type_zero(TYPE_FUNCTION);
3562         function_type_t *ftype = &type->function;
3563
3564         ftype->linkage            = current_linkage;
3565         ftype->calling_convention = CC_DEFAULT;
3566
3567         parse_parameters(ftype, scope);
3568
3569         construct_type_t          *cons     = obstack_alloc(&temp_obst, sizeof(cons->function));
3570         construct_function_type_t *function = &cons->function;
3571         memset(function, 0, sizeof(*function));
3572         cons->kind              = CONSTRUCT_FUNCTION;
3573         function->function_type = type;
3574
3575         return cons;
3576 }
3577
3578 typedef struct parse_declarator_env_t {
3579         bool               may_be_abstract : 1;
3580         bool               must_be_abstract : 1;
3581         decl_modifiers_t   modifiers;
3582         symbol_t          *symbol;
3583         source_position_t  source_position;
3584         scope_t            parameters;
3585         attribute_t       *attributes;
3586 } parse_declarator_env_t;
3587
3588 static construct_type_t *parse_inner_declarator(parse_declarator_env_t *env)
3589 {
3590         /* construct a single linked list of construct_type_t's which describe
3591          * how to construct the final declarator type */
3592         construct_type_t  *first      = NULL;
3593         construct_type_t **anchor     = &first;
3594
3595         env->attributes = parse_attributes(env->attributes);
3596
3597         for (;;) {
3598                 construct_type_t *type;
3599                 //variable_t       *based = NULL; /* MS __based extension */
3600                 switch (token.type) {
3601                         case '&':
3602                                 if (!(c_mode & _CXX))
3603                                         errorf(HERE, "references are only available for C++");
3604                                 type = parse_reference_declarator();
3605                                 break;
3606
3607                         case T__based: {
3608                                 panic("based not supported anymore");
3609                                 /* FALLTHROUGH */
3610                         }
3611
3612                         case '*':
3613                                 type = parse_pointer_declarator();
3614                                 break;
3615
3616                         default:
3617                                 goto ptr_operator_end;
3618                 }
3619
3620                 *anchor = type;
3621                 anchor  = &type->base.next;
3622
3623                 /* TODO: find out if this is correct */
3624                 env->attributes = parse_attributes(env->attributes);
3625         }
3626
3627 ptr_operator_end: ;
3628         construct_type_t *inner_types = NULL;
3629
3630         switch (token.type) {
3631         case T_IDENTIFIER:
3632                 if (env->must_be_abstract) {
3633                         errorf(HERE, "no identifier expected in typename");
3634                 } else {
3635                         env->symbol          = token.symbol;
3636                         env->source_position = token.source_position;
3637                 }
3638                 next_token();
3639                 break;
3640         case '(':
3641                 /* §6.7.6:2 footnote 126:  Empty parentheses in a type name are
3642                  * interpreted as ``function with no parameter specification'', rather
3643                  * than redundant parentheses around the omitted identifier. */
3644                 if (look_ahead(1)->type != ')') {
3645                         next_token();
3646                         add_anchor_token(')');
3647                         inner_types = parse_inner_declarator(env);
3648                         if (inner_types != NULL) {
3649                                 /* All later declarators only modify the return type */
3650                                 env->must_be_abstract = true;
3651                         }
3652                         rem_anchor_token(')');
3653                         expect(')', end_error);
3654                 }
3655                 break;
3656         default:
3657                 if (env->may_be_abstract)
3658                         break;
3659                 parse_error_expected("while parsing declarator", T_IDENTIFIER, '(', NULL);
3660                 eat_until_anchor();
3661                 return NULL;
3662         }
3663
3664         construct_type_t **const p = anchor;
3665
3666         for (;;) {
3667                 construct_type_t *type;
3668                 switch (token.type) {
3669                 case '(': {
3670                         scope_t *scope = NULL;
3671                         if (!env->must_be_abstract) {
3672                                 scope = &env->parameters;
3673                         }
3674
3675                         type = parse_function_declarator(scope);
3676                         break;
3677                 }
3678                 case '[':
3679                         type = parse_array_declarator();
3680                         break;
3681                 default:
3682                         goto declarator_finished;
3683                 }
3684
3685                 /* insert in the middle of the list (at p) */
3686                 type->base.next = *p;
3687                 *p              = type;
3688                 if (anchor == p)
3689                         anchor = &type->base.next;
3690         }
3691
3692 declarator_finished:
3693         /* append inner_types at the end of the list, we don't to set anchor anymore
3694          * as it's not needed anymore */
3695         *anchor = inner_types;
3696
3697         return first;
3698 end_error:
3699         return NULL;
3700 }
3701
3702 static type_t *construct_declarator_type(construct_type_t *construct_list,
3703                                          type_t *type)
3704 {
3705         construct_type_t *iter = construct_list;
3706         for (; iter != NULL; iter = iter->base.next) {
3707                 switch (iter->kind) {
3708                 case CONSTRUCT_INVALID:
3709                         break;
3710                 case CONSTRUCT_FUNCTION: {
3711                         construct_function_type_t *function      = &iter->function;
3712                         type_t                    *function_type = function->function_type;
3713
3714                         function_type->function.return_type = type;
3715
3716                         type_t *skipped_return_type = skip_typeref(type);
3717                         /* §6.7.5.3:1 */
3718                         if (is_type_function(skipped_return_type)) {
3719                                 errorf(HERE, "function returning function is not allowed");
3720                         } else if (is_type_array(skipped_return_type)) {
3721                                 errorf(HERE, "function returning array is not allowed");
3722                         } else {
3723                                 if (skipped_return_type->base.qualifiers != 0 && warning.other) {
3724                                         warningf(HERE,
3725                                                 "type qualifiers in return type of function type are meaningless");
3726                                 }
3727                         }
3728
3729                         /* The function type was constructed earlier.  Freeing it here will
3730                          * destroy other types. */
3731                         type = typehash_insert(function_type);
3732                         continue;
3733                 }
3734
3735                 case CONSTRUCT_POINTER: {
3736                         if (is_type_reference(skip_typeref(type)))
3737                                 errorf(HERE, "cannot declare a pointer to reference");
3738
3739                         parsed_pointer_t *pointer = &iter->pointer;
3740                         type = make_based_pointer_type(type, pointer->type_qualifiers, pointer->base_variable);
3741                         continue;
3742                 }
3743
3744                 case CONSTRUCT_REFERENCE:
3745                         if (is_type_reference(skip_typeref(type)))
3746                                 errorf(HERE, "cannot declare a reference to reference");
3747
3748                         type = make_reference_type(type);
3749                         continue;
3750
3751                 case CONSTRUCT_ARRAY: {
3752                         if (is_type_reference(skip_typeref(type)))
3753                                 errorf(HERE, "cannot declare an array of references");
3754
3755                         parsed_array_t *array      = &iter->array;
3756                         type_t         *array_type = allocate_type_zero(TYPE_ARRAY);
3757
3758                         expression_t *size_expression = array->size;
3759                         if (size_expression != NULL) {
3760                                 size_expression
3761                                         = create_implicit_cast(size_expression, type_size_t);
3762                         }
3763
3764                         array_type->base.qualifiers       = array->type_qualifiers;
3765                         array_type->array.element_type    = type;
3766                         array_type->array.is_static       = array->is_static;
3767                         array_type->array.is_variable     = array->is_variable;
3768                         array_type->array.size_expression = size_expression;
3769
3770                         if (size_expression != NULL) {
3771                                 if (is_constant_expression(size_expression)) {
3772                                         long const size
3773                                                 = fold_constant_to_int(size_expression);
3774                                         array_type->array.size          = size;
3775                                         array_type->array.size_constant = true;
3776                                         /* §6.7.5.2:1  If the expression is a constant expression, it shall
3777                                          * have a value greater than zero. */
3778                                         if (size <= 0) {
3779                                                 if (size < 0 || !GNU_MODE) {
3780                                                         errorf(&size_expression->base.source_position,
3781                                                                         "size of array must be greater than zero");
3782                                                 } else if (warning.other) {
3783                                                         warningf(&size_expression->base.source_position,
3784                                                                         "zero length arrays are a GCC extension");
3785                                                 }
3786                                         }
3787                                 } else {
3788                                         array_type->array.is_vla = true;
3789                                 }
3790                         }
3791
3792                         type_t *skipped_type = skip_typeref(type);
3793                         /* §6.7.5.2:1 */
3794                         if (is_type_incomplete(skipped_type)) {
3795                                 errorf(HERE, "array of incomplete type '%T' is not allowed", type);
3796                         } else if (is_type_function(skipped_type)) {
3797                                 errorf(HERE, "array of functions is not allowed");
3798                         }
3799                         type = identify_new_type(array_type);
3800                         continue;
3801                 }
3802                 }
3803                 internal_errorf(HERE, "invalid type construction found");
3804         }
3805
3806         return type;
3807 }
3808
3809 static type_t *automatic_type_conversion(type_t *orig_type);
3810
3811 static type_t *semantic_parameter(const source_position_t *pos,
3812                                   type_t *type,
3813                                   const declaration_specifiers_t *specifiers,
3814                                   symbol_t *symbol)
3815 {
3816         /* §6.7.5.3:7  A declaration of a parameter as ``array of type''
3817          *             shall be adjusted to ``qualified pointer to type'',
3818          *             [...]
3819          * §6.7.5.3:8  A declaration of a parameter as ``function returning
3820          *             type'' shall be adjusted to ``pointer to function
3821          *             returning type'', as in 6.3.2.1. */
3822         type = automatic_type_conversion(type);
3823
3824         if (specifiers->is_inline && is_type_valid(type)) {
3825                 errorf(pos, "parameter '%#T' declared 'inline'", type, symbol);
3826         }
3827
3828         /* §6.9.1:6  The declarations in the declaration list shall contain
3829          *           no storage-class specifier other than register and no
3830          *           initializations. */
3831         if (specifiers->thread_local || (
3832                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
3833                         specifiers->storage_class != STORAGE_CLASS_REGISTER)
3834            ) {
3835                 errorf(pos, "invalid storage class for parameter '%#T'", type, symbol);
3836         }
3837
3838         /* delay test for incomplete type, because we might have (void)
3839          * which is legal but incomplete... */
3840
3841         return type;
3842 }
3843
3844 static entity_t *parse_declarator(const declaration_specifiers_t *specifiers,
3845                                   declarator_flags_t flags)
3846 {
3847         parse_declarator_env_t env;
3848         memset(&env, 0, sizeof(env));
3849         env.may_be_abstract = (flags & DECL_MAY_BE_ABSTRACT) != 0;
3850
3851         construct_type_t *construct_type = parse_inner_declarator(&env);
3852         type_t           *orig_type      =
3853                 construct_declarator_type(construct_type, specifiers->type);
3854         type_t           *type           = skip_typeref(orig_type);
3855
3856         if (construct_type != NULL) {
3857                 obstack_free(&temp_obst, construct_type);
3858         }
3859
3860         attribute_t *attributes = parse_attributes(env.attributes);
3861         /* append (shared) specifier attribute behind attributes of this
3862          * declarator */
3863         attribute_t **anchor = &attributes;
3864         while (*anchor != NULL)
3865                 anchor = &(*anchor)->next;
3866         *anchor = specifiers->attributes;
3867
3868         entity_t *entity;
3869         if (specifiers->storage_class == STORAGE_CLASS_TYPEDEF) {
3870                 entity                       = allocate_entity_zero(ENTITY_TYPEDEF);
3871                 entity->base.symbol          = env.symbol;
3872                 entity->base.source_position = env.source_position;
3873                 entity->typedefe.type        = orig_type;
3874
3875                 if (anonymous_entity != NULL) {
3876                         if (is_type_compound(type)) {
3877                                 assert(anonymous_entity->compound.alias == NULL);
3878                                 assert(anonymous_entity->kind == ENTITY_STRUCT ||
3879                                        anonymous_entity->kind == ENTITY_UNION);
3880                                 anonymous_entity->compound.alias = entity;
3881                                 anonymous_entity = NULL;
3882                         } else if (is_type_enum(type)) {
3883                                 assert(anonymous_entity->enume.alias == NULL);
3884                                 assert(anonymous_entity->kind == ENTITY_ENUM);
3885                                 anonymous_entity->enume.alias = entity;
3886                                 anonymous_entity = NULL;
3887                         }
3888                 }
3889         } else {
3890                 /* create a declaration type entity */
3891                 if (flags & DECL_CREATE_COMPOUND_MEMBER) {
3892                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
3893
3894                         if (env.symbol != NULL) {
3895                                 if (specifiers->is_inline && is_type_valid(type)) {
3896                                         errorf(&env.source_position,
3897                                                         "compound member '%Y' declared 'inline'", env.symbol);
3898                                 }
3899
3900                                 if (specifiers->thread_local ||
3901                                                 specifiers->storage_class != STORAGE_CLASS_NONE) {
3902                                         errorf(&env.source_position,
3903                                                         "compound member '%Y' must have no storage class",
3904                                                         env.symbol);
3905                                 }
3906                         }
3907                 } else if (flags & DECL_IS_PARAMETER) {
3908                         orig_type = semantic_parameter(&env.source_position, orig_type,
3909                                                        specifiers, env.symbol);
3910
3911                         entity = allocate_entity_zero(ENTITY_PARAMETER);
3912                 } else if (is_type_function(type)) {
3913                         entity = allocate_entity_zero(ENTITY_FUNCTION);
3914
3915                         entity->function.is_inline  = specifiers->is_inline;
3916                         entity->function.parameters = env.parameters;
3917
3918                         if (env.symbol != NULL) {
3919                                 /* this needs fixes for C++ */
3920                                 bool in_function_scope = current_function != NULL;
3921
3922                                 if (specifiers->thread_local || (
3923                                       specifiers->storage_class != STORAGE_CLASS_EXTERN &&
3924                                           specifiers->storage_class != STORAGE_CLASS_NONE   &&
3925                                           (in_function_scope || specifiers->storage_class != STORAGE_CLASS_STATIC)
3926                                    )) {
3927                                         errorf(&env.source_position,
3928                                                         "invalid storage class for function '%Y'", env.symbol);
3929                                 }
3930                         }
3931                 } else {
3932                         entity = allocate_entity_zero(ENTITY_VARIABLE);
3933
3934                         entity->variable.thread_local = specifiers->thread_local;
3935
3936                         if (env.symbol != NULL) {
3937                                 if (specifiers->is_inline && is_type_valid(type)) {
3938                                         errorf(&env.source_position,
3939                                                         "variable '%Y' declared 'inline'", env.symbol);
3940                                 }
3941
3942                                 bool invalid_storage_class = false;
3943                                 if (current_scope == file_scope) {
3944                                         if (specifiers->storage_class != STORAGE_CLASS_EXTERN &&
3945                                                         specifiers->storage_class != STORAGE_CLASS_NONE   &&
3946                                                         specifiers->storage_class != STORAGE_CLASS_STATIC) {
3947                                                 invalid_storage_class = true;
3948                                         }
3949                                 } else {
3950                                         if (specifiers->thread_local &&
3951                                                         specifiers->storage_class == STORAGE_CLASS_NONE) {
3952                                                 invalid_storage_class = true;
3953                                         }
3954                                 }
3955                                 if (invalid_storage_class) {
3956                                         errorf(&env.source_position,
3957                                                         "invalid storage class for variable '%Y'", env.symbol);
3958                                 }
3959                         }
3960                 }
3961
3962                 if (env.symbol != NULL) {
3963                         entity->base.symbol          = env.symbol;
3964                         entity->base.source_position = env.source_position;
3965                 } else {
3966                         entity->base.source_position = specifiers->source_position;
3967                 }
3968                 entity->base.namespc           = NAMESPACE_NORMAL;
3969                 entity->declaration.type       = orig_type;
3970                 entity->declaration.alignment  = get_type_alignment(orig_type);
3971                 entity->declaration.modifiers  = env.modifiers;
3972                 entity->declaration.attributes = attributes;
3973
3974                 storage_class_t storage_class = specifiers->storage_class;
3975                 entity->declaration.declared_storage_class = storage_class;
3976
3977                 if (storage_class == STORAGE_CLASS_NONE && current_function != NULL)
3978                         storage_class = STORAGE_CLASS_AUTO;
3979                 entity->declaration.storage_class = storage_class;
3980         }
3981
3982         if (attributes != NULL) {
3983                 handle_entity_attributes(attributes, entity);
3984         }
3985
3986         return entity;
3987 }
3988
3989 static type_t *parse_abstract_declarator(type_t *base_type)
3990 {
3991         parse_declarator_env_t env;
3992         memset(&env, 0, sizeof(env));
3993         env.may_be_abstract = true;
3994         env.must_be_abstract = true;
3995
3996         construct_type_t *construct_type = parse_inner_declarator(&env);
3997
3998         type_t *result = construct_declarator_type(construct_type, base_type);
3999         if (construct_type != NULL) {
4000                 obstack_free(&temp_obst, construct_type);
4001         }
4002         result = handle_type_attributes(env.attributes, result);
4003
4004         return result;
4005 }
4006
4007 /**
4008  * Check if the declaration of main is suspicious.  main should be a
4009  * function with external linkage, returning int, taking either zero
4010  * arguments, two, or three arguments of appropriate types, ie.
4011  *
4012  * int main([ int argc, char **argv [, char **env ] ]).
4013  *
4014  * @param decl    the declaration to check
4015  * @param type    the function type of the declaration
4016  */
4017 static void check_main(const entity_t *entity)
4018 {
4019         const source_position_t *pos = &entity->base.source_position;
4020         if (entity->kind != ENTITY_FUNCTION) {
4021                 warningf(pos, "'main' is not a function");
4022                 return;
4023         }
4024
4025         if (entity->declaration.storage_class == STORAGE_CLASS_STATIC) {
4026                 warningf(pos, "'main' is normally a non-static function");
4027         }
4028
4029         type_t *type = skip_typeref(entity->declaration.type);
4030         assert(is_type_function(type));
4031
4032         function_type_t *func_type = &type->function;
4033         if (!types_compatible(skip_typeref(func_type->return_type), type_int)) {
4034                 warningf(pos, "return type of 'main' should be 'int', but is '%T'",
4035                          func_type->return_type);
4036         }
4037         const function_parameter_t *parm = func_type->parameters;
4038         if (parm != NULL) {
4039                 type_t *const first_type = parm->type;
4040                 if (!types_compatible(skip_typeref(first_type), type_int)) {
4041                         warningf(pos,
4042                                  "first argument of 'main' should be 'int', but is '%T'",
4043                                  first_type);
4044                 }
4045                 parm = parm->next;
4046                 if (parm != NULL) {
4047                         type_t *const second_type = parm->type;
4048                         if (!types_compatible(skip_typeref(second_type), type_char_ptr_ptr)) {
4049                                 warningf(pos, "second argument of 'main' should be 'char**', but is '%T'", second_type);
4050                         }
4051                         parm = parm->next;
4052                         if (parm != NULL) {
4053                                 type_t *const third_type = parm->type;
4054                                 if (!types_compatible(skip_typeref(third_type), type_char_ptr_ptr)) {
4055                                         warningf(pos, "third argument of 'main' should be 'char**', but is '%T'", third_type);
4056                                 }
4057                                 parm = parm->next;
4058                                 if (parm != NULL)
4059                                         goto warn_arg_count;
4060                         }
4061                 } else {
4062 warn_arg_count:
4063                         warningf(pos, "'main' takes only zero, two or three arguments");
4064                 }
4065         }
4066 }
4067
4068 /**
4069  * Check if a symbol is the equal to "main".
4070  */
4071 static bool is_sym_main(const symbol_t *const sym)
4072 {
4073         return strcmp(sym->string, "main") == 0;
4074 }
4075
4076 static void error_redefined_as_different_kind(const source_position_t *pos,
4077                 const entity_t *old, entity_kind_t new_kind)
4078 {
4079         errorf(pos, "redeclaration of %s '%Y' as %s (declared %P)",
4080                get_entity_kind_name(old->kind), old->base.symbol,
4081                get_entity_kind_name(new_kind), &old->base.source_position);
4082 }
4083
4084 static bool is_error_entity(entity_t *const ent)
4085 {
4086         if (is_declaration(ent)) {
4087                 return is_type_valid(skip_typeref(ent->declaration.type));
4088         } else if (ent->kind == ENTITY_TYPEDEF) {
4089                 return is_type_valid(skip_typeref(ent->typedefe.type));
4090         }
4091         return false;
4092 }
4093
4094 static bool contains_attribute(const attribute_t *list, const attribute_t *attr)
4095 {
4096         for (const attribute_t *tattr = list; tattr != NULL; tattr = tattr->next) {
4097                 if (attributes_equal(tattr, attr))
4098                         return true;
4099         }
4100         return false;
4101 }
4102
4103 /**
4104  * test wether new_list contains any attributes not included in old_list
4105  */
4106 static bool has_new_attributes(const attribute_t *old_list,
4107                                const attribute_t *new_list)
4108 {
4109         for (const attribute_t *attr = new_list; attr != NULL; attr = attr->next) {
4110                 if (!contains_attribute(old_list, attr))
4111                         return true;
4112         }
4113         return false;
4114 }
4115
4116 /**
4117  * Merge in attributes from an attribute list (probably from a previous
4118  * declaration with the same name). Warning: destroys the old structure
4119  * of the attribute list - don't reuse attributes after this call.
4120  */
4121 static void merge_in_attributes(declaration_t *decl, attribute_t *attributes)
4122 {
4123         attribute_t *next;
4124         for (attribute_t *attr = attributes; attr != NULL; attr = next) {
4125                 next = attr->next;
4126                 if (contains_attribute(decl->attributes, attr))
4127                         continue;
4128
4129                 /* move attribute to new declarations attributes list */
4130                 attr->next       = decl->attributes;
4131                 decl->attributes = attr;
4132         }
4133 }
4134
4135 /**
4136  * record entities for the NAMESPACE_NORMAL, and produce error messages/warnings
4137  * for various problems that occur for multiple definitions
4138  */
4139 entity_t *record_entity(entity_t *entity, const bool is_definition)
4140 {
4141         const symbol_t *const    symbol  = entity->base.symbol;
4142         const namespace_tag_t    namespc = (namespace_tag_t)entity->base.namespc;
4143         const source_position_t *pos     = &entity->base.source_position;
4144
4145         /* can happen in error cases */
4146         if (symbol == NULL)
4147                 return entity;
4148
4149         entity_t *const previous_entity = get_entity(symbol, namespc);
4150         /* pushing the same entity twice will break the stack structure */
4151         assert(previous_entity != entity);
4152
4153         if (entity->kind == ENTITY_FUNCTION) {
4154                 type_t *const orig_type = entity->declaration.type;
4155                 type_t *const type      = skip_typeref(orig_type);
4156
4157                 assert(is_type_function(type));
4158                 if (type->function.unspecified_parameters &&
4159                                 warning.strict_prototypes &&
4160                                 previous_entity == NULL) {
4161                         warningf(pos, "function declaration '%#T' is not a prototype",
4162                                          orig_type, symbol);
4163                 }
4164
4165                 if (warning.main && current_scope == file_scope
4166                                 && is_sym_main(symbol)) {
4167                         check_main(entity);
4168                 }
4169         }
4170
4171         if (is_declaration(entity) &&
4172                         warning.nested_externs &&
4173                         entity->declaration.storage_class == STORAGE_CLASS_EXTERN &&
4174                         current_scope != file_scope) {
4175                 warningf(pos, "nested extern declaration of '%#T'",
4176                          entity->declaration.type, symbol);
4177         }
4178
4179         if (previous_entity != NULL) {
4180                 if (previous_entity->base.parent_scope == &current_function->parameters &&
4181                                 previous_entity->base.parent_scope->depth + 1 == current_scope->depth) {
4182                         assert(previous_entity->kind == ENTITY_PARAMETER);
4183                         errorf(pos,
4184                                         "declaration '%#T' redeclares the parameter '%#T' (declared %P)",
4185                                         entity->declaration.type, symbol,
4186                                         previous_entity->declaration.type, symbol,
4187                                         &previous_entity->base.source_position);
4188                         goto finish;
4189                 }
4190
4191                 if (previous_entity->base.parent_scope == current_scope) {
4192                         if (previous_entity->kind != entity->kind) {
4193                                 if (!is_error_entity(previous_entity) && !is_error_entity(entity)) {
4194                                         error_redefined_as_different_kind(pos, previous_entity,
4195                                                         entity->kind);
4196                                 }
4197                                 goto finish;
4198                         }
4199                         if (previous_entity->kind == ENTITY_ENUM_VALUE) {
4200                                 errorf(pos, "redeclaration of enum entry '%Y' (declared %P)",
4201                                                 symbol, &previous_entity->base.source_position);
4202                                 goto finish;
4203                         }
4204                         if (previous_entity->kind == ENTITY_TYPEDEF) {
4205                                 /* TODO: C++ allows this for exactly the same type */
4206                                 errorf(pos, "redefinition of typedef '%Y' (declared %P)",
4207                                                 symbol, &previous_entity->base.source_position);
4208                                 goto finish;
4209                         }
4210
4211                         /* at this point we should have only VARIABLES or FUNCTIONS */
4212                         assert(is_declaration(previous_entity) && is_declaration(entity));
4213
4214                         declaration_t *const prev_decl = &previous_entity->declaration;
4215                         declaration_t *const decl      = &entity->declaration;
4216
4217                         /* can happen for K&R style declarations */
4218                         if (prev_decl->type       == NULL             &&
4219                                         previous_entity->kind == ENTITY_PARAMETER &&
4220                                         entity->kind          == ENTITY_PARAMETER) {
4221                                 prev_decl->type                   = decl->type;
4222                                 prev_decl->storage_class          = decl->storage_class;
4223                                 prev_decl->declared_storage_class = decl->declared_storage_class;
4224                                 prev_decl->modifiers              = decl->modifiers;
4225                                 return previous_entity;
4226                         }
4227
4228                         type_t *const orig_type = decl->type;
4229                         assert(orig_type != NULL);
4230                         type_t *const type      = skip_typeref(orig_type);
4231                         type_t *const prev_type = skip_typeref(prev_decl->type);
4232
4233                         if (!types_compatible(type, prev_type)) {
4234                                 errorf(pos,
4235                                                 "declaration '%#T' is incompatible with '%#T' (declared %P)",
4236                                                 orig_type, symbol, prev_decl->type, symbol,
4237                                                 &previous_entity->base.source_position);
4238                         } else {
4239                                 unsigned old_storage_class = prev_decl->storage_class;
4240
4241                                 if (warning.redundant_decls               &&
4242                                                 is_definition                     &&
4243                                                 !prev_decl->used                  &&
4244                                                 !(prev_decl->modifiers & DM_USED) &&
4245                                                 prev_decl->storage_class == STORAGE_CLASS_STATIC) {
4246                                         warningf(&previous_entity->base.source_position,
4247                                                         "unnecessary static forward declaration for '%#T'",
4248                                                         prev_decl->type, symbol);
4249                                 }
4250
4251                                 storage_class_t new_storage_class = decl->storage_class;
4252
4253                                 /* pretend no storage class means extern for function
4254                                  * declarations (except if the previous declaration is neither
4255                                  * none nor extern) */
4256                                 if (entity->kind == ENTITY_FUNCTION) {
4257                                         /* the previous declaration could have unspecified parameters or
4258                                          * be a typedef, so use the new type */
4259                                         if (prev_type->function.unspecified_parameters || is_definition)
4260                                                 prev_decl->type = type;
4261
4262                                         switch (old_storage_class) {
4263                                                 case STORAGE_CLASS_NONE:
4264                                                         old_storage_class = STORAGE_CLASS_EXTERN;
4265                                                         /* FALLTHROUGH */
4266
4267                                                 case STORAGE_CLASS_EXTERN:
4268                                                         if (is_definition) {
4269                                                                 if (warning.missing_prototypes &&
4270                                                                                 prev_type->function.unspecified_parameters &&
4271                                                                                 !is_sym_main(symbol)) {
4272                                                                         warningf(pos, "no previous prototype for '%#T'",
4273                                                                                         orig_type, symbol);
4274                                                                 }
4275                                                         } else if (new_storage_class == STORAGE_CLASS_NONE) {
4276                                                                 new_storage_class = STORAGE_CLASS_EXTERN;
4277                                                         }
4278                                                         break;
4279
4280                                                 default:
4281                                                         break;
4282                                         }
4283                                 } else if (is_type_incomplete(prev_type)) {
4284                                         prev_decl->type = type;
4285                                 }
4286
4287                                 if (old_storage_class == STORAGE_CLASS_EXTERN &&
4288                                                 new_storage_class == STORAGE_CLASS_EXTERN) {
4289
4290 warn_redundant_declaration: ;
4291                                         bool has_new_attrs
4292                                                 = has_new_attributes(prev_decl->attributes,
4293                                                                      decl->attributes);
4294                                         if (has_new_attrs) {
4295                                                 merge_in_attributes(decl, prev_decl->attributes);
4296                                         } else if (!is_definition        &&
4297                                                         warning.redundant_decls  &&
4298                                                         is_type_valid(prev_type) &&
4299                                                         strcmp(previous_entity->base.source_position.input_name,
4300                                                                 "<builtin>") != 0) {
4301                                                 warningf(pos,
4302                                                          "redundant declaration for '%Y' (declared %P)",
4303                                                          symbol, &previous_entity->base.source_position);
4304                                         }
4305                                 } else if (current_function == NULL) {
4306                                         if (old_storage_class != STORAGE_CLASS_STATIC &&
4307                                                         new_storage_class == STORAGE_CLASS_STATIC) {
4308                                                 errorf(pos,
4309                                                        "static declaration of '%Y' follows non-static declaration (declared %P)",
4310                                                        symbol, &previous_entity->base.source_position);
4311                                         } else if (old_storage_class == STORAGE_CLASS_EXTERN) {
4312                                                 prev_decl->storage_class          = STORAGE_CLASS_NONE;
4313                                                 prev_decl->declared_storage_class = STORAGE_CLASS_NONE;
4314                                         } else {
4315                                                 /* ISO/IEC 14882:1998(E) §C.1.2:1 */
4316                                                 if (c_mode & _CXX)
4317                                                         goto error_redeclaration;
4318                                                 goto warn_redundant_declaration;
4319                                         }
4320                                 } else if (is_type_valid(prev_type)) {
4321                                         if (old_storage_class == new_storage_class) {
4322 error_redeclaration:
4323                                                 errorf(pos, "redeclaration of '%Y' (declared %P)",
4324                                                                 symbol, &previous_entity->base.source_position);
4325                                         } else {
4326                                                 errorf(pos,
4327                                                                 "redeclaration of '%Y' with different linkage (declared %P)",
4328                                                                 symbol, &previous_entity->base.source_position);
4329                                         }
4330                                 }
4331                         }
4332
4333                         prev_decl->modifiers |= decl->modifiers;
4334                         if (entity->kind == ENTITY_FUNCTION) {
4335                                 previous_entity->function.is_inline |= entity->function.is_inline;
4336                         }
4337                         return previous_entity;
4338                 }
4339
4340                 if (warning.shadow) {
4341                         warningf(pos, "%s '%Y' shadows %s (declared %P)",
4342                                         get_entity_kind_name(entity->kind), symbol,
4343                                         get_entity_kind_name(previous_entity->kind),
4344                                         &previous_entity->base.source_position);
4345                 }
4346         }
4347
4348         if (entity->kind == ENTITY_FUNCTION) {
4349                 if (is_definition &&
4350                                 entity->declaration.storage_class != STORAGE_CLASS_STATIC) {
4351                         if (warning.missing_prototypes && !is_sym_main(symbol)) {
4352                                 warningf(pos, "no previous prototype for '%#T'",
4353                                          entity->declaration.type, symbol);
4354                         } else if (warning.missing_declarations && !is_sym_main(symbol)) {
4355                                 warningf(pos, "no previous declaration for '%#T'",
4356                                          entity->declaration.type, symbol);
4357                         }
4358                 }
4359         } else if (warning.missing_declarations &&
4360                         entity->kind == ENTITY_VARIABLE &&
4361                         current_scope == file_scope) {
4362                 declaration_t *declaration = &entity->declaration;
4363                 if (declaration->storage_class == STORAGE_CLASS_NONE) {
4364                         warningf(pos, "no previous declaration for '%#T'",
4365                                  declaration->type, symbol);
4366                 }
4367         }
4368
4369 finish:
4370         assert(entity->base.parent_scope == NULL);
4371         assert(current_scope != NULL);
4372
4373         entity->base.parent_scope = current_scope;
4374         entity->base.namespc      = NAMESPACE_NORMAL;
4375         environment_push(entity);
4376         append_entity(current_scope, entity);
4377
4378         return entity;
4379 }
4380
4381 static void parser_error_multiple_definition(entity_t *entity,
4382                 const source_position_t *source_position)
4383 {
4384         errorf(source_position, "multiple definition of '%Y' (declared %P)",
4385                entity->base.symbol, &entity->base.source_position);
4386 }
4387
4388 static bool is_declaration_specifier(const token_t *token,
4389                                      bool only_specifiers_qualifiers)
4390 {
4391         switch (token->type) {
4392                 TYPE_SPECIFIERS
4393                 TYPE_QUALIFIERS
4394                         return true;
4395                 case T_IDENTIFIER:
4396                         return is_typedef_symbol(token->symbol);
4397
4398                 case T___extension__:
4399                 STORAGE_CLASSES
4400                         return !only_specifiers_qualifiers;
4401
4402                 default:
4403                         return false;
4404         }
4405 }
4406
4407 static void parse_init_declarator_rest(entity_t *entity)
4408 {
4409         assert(is_declaration(entity));
4410         declaration_t *const declaration = &entity->declaration;
4411
4412         eat('=');
4413
4414         type_t *orig_type = declaration->type;
4415         type_t *type      = skip_typeref(orig_type);
4416
4417         if (entity->kind == ENTITY_VARIABLE
4418                         && entity->variable.initializer != NULL) {
4419                 parser_error_multiple_definition(entity, HERE);
4420         }
4421
4422         bool must_be_constant = false;
4423         if (declaration->storage_class == STORAGE_CLASS_STATIC ||
4424             entity->base.parent_scope  == file_scope) {
4425                 must_be_constant = true;
4426         }
4427
4428         if (is_type_function(type)) {
4429                 errorf(&entity->base.source_position,
4430                        "function '%#T' is initialized like a variable",
4431                        orig_type, entity->base.symbol);
4432                 orig_type = type_error_type;
4433         }
4434
4435         parse_initializer_env_t env;
4436         env.type             = orig_type;
4437         env.must_be_constant = must_be_constant;
4438         env.entity           = entity;
4439         current_init_decl    = entity;
4440
4441         initializer_t *initializer = parse_initializer(&env);
4442         current_init_decl = NULL;
4443
4444         if (entity->kind == ENTITY_VARIABLE) {
4445                 /* §6.7.5:22  array initializers for arrays with unknown size
4446                  * determine the array type size */
4447                 declaration->type            = env.type;
4448                 entity->variable.initializer = initializer;
4449         }
4450 }
4451
4452 /* parse rest of a declaration without any declarator */
4453 static void parse_anonymous_declaration_rest(
4454                 const declaration_specifiers_t *specifiers)
4455 {
4456         eat(';');
4457         anonymous_entity = NULL;
4458
4459         if (warning.other) {
4460                 if (specifiers->storage_class != STORAGE_CLASS_NONE ||
4461                                 specifiers->thread_local) {
4462                         warningf(&specifiers->source_position,
4463                                  "useless storage class in empty declaration");
4464                 }
4465
4466                 type_t *type = specifiers->type;
4467                 switch (type->kind) {
4468                         case TYPE_COMPOUND_STRUCT:
4469                         case TYPE_COMPOUND_UNION: {
4470                                 if (type->compound.compound->base.symbol == NULL) {
4471                                         warningf(&specifiers->source_position,
4472                                                  "unnamed struct/union that defines no instances");
4473                                 }
4474                                 break;
4475                         }
4476
4477                         case TYPE_ENUM:
4478                                 break;
4479
4480                         default:
4481                                 warningf(&specifiers->source_position, "empty declaration");
4482                                 break;
4483                 }
4484         }
4485 }
4486
4487 static void check_variable_type_complete(entity_t *ent)
4488 {
4489         if (ent->kind != ENTITY_VARIABLE)
4490                 return;
4491
4492         /* §6.7:7  If an identifier for an object is declared with no linkage, the
4493          *         type for the object shall be complete [...] */
4494         declaration_t *decl = &ent->declaration;
4495         if (decl->storage_class == STORAGE_CLASS_EXTERN ||
4496                         decl->storage_class == STORAGE_CLASS_STATIC)
4497                 return;
4498
4499         type_t *const orig_type = decl->type;
4500         type_t *const type      = skip_typeref(orig_type);
4501         if (!is_type_incomplete(type))
4502                 return;
4503
4504         /* §6.9.2:2 and §6.9.2:5: At the end of the translation incomplete arrays
4505          * are given length one. */
4506         if (is_type_array(type) && ent->base.parent_scope == file_scope) {
4507                 ARR_APP1(declaration_t*, incomplete_arrays, decl);
4508                 return;
4509         }
4510
4511         errorf(&ent->base.source_position, "variable '%#T' has incomplete type",
4512                         orig_type, ent->base.symbol);
4513 }
4514
4515
4516 static void parse_declaration_rest(entity_t *ndeclaration,
4517                 const declaration_specifiers_t *specifiers,
4518                 parsed_declaration_func         finished_declaration,
4519                 declarator_flags_t              flags)
4520 {
4521         add_anchor_token(';');
4522         add_anchor_token(',');
4523         while (true) {
4524                 entity_t *entity = finished_declaration(ndeclaration, token.type == '=');
4525
4526                 if (token.type == '=') {
4527                         parse_init_declarator_rest(entity);
4528                 } else if (entity->kind == ENTITY_VARIABLE) {
4529                         /* ISO/IEC 14882:1998(E) §8.5.3:3  The initializer can be omitted
4530                          * [...] where the extern specifier is explicitly used. */
4531                         declaration_t *decl = &entity->declaration;
4532                         if (decl->storage_class != STORAGE_CLASS_EXTERN) {
4533                                 type_t *type = decl->type;
4534                                 if (is_type_reference(skip_typeref(type))) {
4535                                         errorf(&entity->base.source_position,
4536                                                         "reference '%#T' must be initialized",
4537                                                         type, entity->base.symbol);
4538                                 }
4539                         }
4540                 }
4541
4542                 check_variable_type_complete(entity);
4543
4544                 if (!next_if(','))
4545                         break;
4546
4547                 add_anchor_token('=');
4548                 ndeclaration = parse_declarator(specifiers, flags);
4549                 rem_anchor_token('=');
4550         }
4551         expect(';', end_error);
4552
4553 end_error:
4554         anonymous_entity = NULL;
4555         rem_anchor_token(';');
4556         rem_anchor_token(',');
4557 }
4558
4559 static entity_t *finished_kr_declaration(entity_t *entity, bool is_definition)
4560 {
4561         symbol_t *symbol = entity->base.symbol;
4562         if (symbol == NULL) {
4563                 errorf(HERE, "anonymous declaration not valid as function parameter");
4564                 return entity;
4565         }
4566
4567         assert(entity->base.namespc == NAMESPACE_NORMAL);
4568         entity_t *previous_entity = get_entity(symbol, NAMESPACE_NORMAL);
4569         if (previous_entity == NULL
4570                         || previous_entity->base.parent_scope != current_scope) {
4571                 errorf(HERE, "expected declaration of a function parameter, found '%Y'",
4572                        symbol);
4573                 return entity;
4574         }
4575
4576         if (is_definition) {
4577                 errorf(HERE, "parameter '%Y' is initialised", entity->base.symbol);
4578         }
4579
4580         return record_entity(entity, false);
4581 }
4582
4583 static void parse_declaration(parsed_declaration_func finished_declaration,
4584                               declarator_flags_t      flags)
4585 {
4586         declaration_specifiers_t specifiers;
4587         memset(&specifiers, 0, sizeof(specifiers));
4588
4589         add_anchor_token(';');
4590         parse_declaration_specifiers(&specifiers);
4591         rem_anchor_token(';');
4592
4593         if (token.type == ';') {
4594                 parse_anonymous_declaration_rest(&specifiers);
4595         } else {
4596                 entity_t *entity = parse_declarator(&specifiers, flags);
4597                 parse_declaration_rest(entity, &specifiers, finished_declaration, flags);
4598         }
4599 }
4600
4601 /* §6.5.2.2:6 */
4602 static type_t *get_default_promoted_type(type_t *orig_type)
4603 {
4604         type_t *result = orig_type;
4605
4606         type_t *type = skip_typeref(orig_type);
4607         if (is_type_integer(type)) {
4608                 result = promote_integer(type);
4609         } else if (is_type_atomic(type, ATOMIC_TYPE_FLOAT)) {
4610                 result = type_double;
4611         }
4612
4613         return result;
4614 }
4615
4616 static void parse_kr_declaration_list(entity_t *entity)
4617 {
4618         if (entity->kind != ENTITY_FUNCTION)
4619                 return;
4620
4621         type_t *type = skip_typeref(entity->declaration.type);
4622         assert(is_type_function(type));
4623         if (!type->function.kr_style_parameters)
4624                 return;
4625
4626         add_anchor_token('{');
4627
4628         /* push function parameters */
4629         size_t const  top       = environment_top();
4630         scope_t      *old_scope = scope_push(&entity->function.parameters);
4631
4632         entity_t *parameter = entity->function.parameters.entities;
4633         for ( ; parameter != NULL; parameter = parameter->base.next) {
4634                 assert(parameter->base.parent_scope == NULL);
4635                 parameter->base.parent_scope = current_scope;
4636                 environment_push(parameter);
4637         }
4638
4639         /* parse declaration list */
4640         for (;;) {
4641                 switch (token.type) {
4642                         DECLARATION_START
4643                         case T___extension__:
4644                         /* This covers symbols, which are no type, too, and results in
4645                          * better error messages.  The typical cases are misspelled type
4646                          * names and missing includes. */
4647                         case T_IDENTIFIER:
4648                                 parse_declaration(finished_kr_declaration, DECL_IS_PARAMETER);
4649                                 break;
4650                         default:
4651                                 goto decl_list_end;
4652                 }
4653         }
4654 decl_list_end:
4655
4656         /* pop function parameters */
4657         assert(current_scope == &entity->function.parameters);
4658         scope_pop(old_scope);
4659         environment_pop_to(top);
4660
4661         /* update function type */
4662         type_t *new_type = duplicate_type(type);
4663
4664         function_parameter_t  *parameters = NULL;
4665         function_parameter_t **anchor     = &parameters;
4666
4667         /* did we have an earlier prototype? */
4668         entity_t *proto_type = get_entity(entity->base.symbol, NAMESPACE_NORMAL);
4669         if (proto_type != NULL && proto_type->kind != ENTITY_FUNCTION)
4670                 proto_type = NULL;
4671
4672         function_parameter_t *proto_parameter = NULL;
4673         if (proto_type != NULL) {
4674                 type_t *proto_type_type = proto_type->declaration.type;
4675                 proto_parameter         = proto_type_type->function.parameters;
4676                 /* If a K&R function definition has a variadic prototype earlier, then
4677                  * make the function definition variadic, too. This should conform to
4678                  * §6.7.5.3:15 and §6.9.1:8. */
4679                 new_type->function.variadic = proto_type_type->function.variadic;
4680         } else {
4681                 /* §6.9.1.7: A K&R style parameter list does NOT act as a function
4682                  * prototype */
4683                 new_type->function.unspecified_parameters = true;
4684         }
4685
4686         bool need_incompatible_warning = false;
4687         parameter = entity->function.parameters.entities;
4688         for (; parameter != NULL; parameter = parameter->base.next,
4689                         proto_parameter =
4690                                 proto_parameter == NULL ? NULL : proto_parameter->next) {
4691                 if (parameter->kind != ENTITY_PARAMETER)
4692                         continue;
4693
4694                 type_t *parameter_type = parameter->declaration.type;
4695                 if (parameter_type == NULL) {
4696                         if (strict_mode) {
4697                                 errorf(HERE, "no type specified for function parameter '%Y'",
4698                                        parameter->base.symbol);
4699                                 parameter_type = type_error_type;
4700                         } else {
4701                                 if (warning.implicit_int) {
4702                                         warningf(HERE, "no type specified for function parameter '%Y', using 'int'",
4703                                                  parameter->base.symbol);
4704                                 }
4705                                 parameter_type = type_int;
4706                         }
4707                         parameter->declaration.type = parameter_type;
4708                 }
4709
4710                 semantic_parameter_incomplete(parameter);
4711
4712                 /* we need the default promoted types for the function type */
4713                 type_t *not_promoted = parameter_type;
4714                 parameter_type       = get_default_promoted_type(parameter_type);
4715
4716                 /* gcc special: if the type of the prototype matches the unpromoted
4717                  * type don't promote */
4718                 if (!strict_mode && proto_parameter != NULL) {
4719                         type_t *proto_p_type = skip_typeref(proto_parameter->type);
4720                         type_t *promo_skip   = skip_typeref(parameter_type);
4721                         type_t *param_skip   = skip_typeref(not_promoted);
4722                         if (!types_compatible(proto_p_type, promo_skip)
4723                                 && types_compatible(proto_p_type, param_skip)) {
4724                                 /* don't promote */
4725                                 need_incompatible_warning = true;
4726                                 parameter_type = not_promoted;
4727                         }
4728                 }
4729                 function_parameter_t *const parameter
4730                         = allocate_parameter(parameter_type);
4731
4732                 *anchor = parameter;
4733                 anchor  = &parameter->next;
4734         }
4735
4736         new_type->function.parameters = parameters;
4737         new_type = identify_new_type(new_type);
4738
4739         if (warning.other && need_incompatible_warning) {
4740                 type_t *proto_type_type = proto_type->declaration.type;
4741                 warningf(HERE,
4742                          "declaration '%#T' is incompatible with '%#T' (declared %P)",
4743                          proto_type_type, proto_type->base.symbol,
4744                          new_type, entity->base.symbol,
4745                          &proto_type->base.source_position);
4746         }
4747
4748         entity->declaration.type = new_type;
4749
4750         rem_anchor_token('{');
4751 }
4752
4753 static bool first_err = true;
4754
4755 /**
4756  * When called with first_err set, prints the name of the current function,
4757  * else does noting.
4758  */
4759 static void print_in_function(void)
4760 {
4761         if (first_err) {
4762                 first_err = false;
4763                 diagnosticf("%s: In function '%Y':\n",
4764                             current_function->base.base.source_position.input_name,
4765                             current_function->base.base.symbol);
4766         }
4767 }
4768
4769 /**
4770  * Check if all labels are defined in the current function.
4771  * Check if all labels are used in the current function.
4772  */
4773 static void check_labels(void)
4774 {
4775         for (const goto_statement_t *goto_statement = goto_first;
4776             goto_statement != NULL;
4777             goto_statement = goto_statement->next) {
4778                 /* skip computed gotos */
4779                 if (goto_statement->expression != NULL)
4780                         continue;
4781
4782                 label_t *label = goto_statement->label;
4783
4784                 label->used = true;
4785                 if (label->base.source_position.input_name == NULL) {
4786                         print_in_function();
4787                         errorf(&goto_statement->base.source_position,
4788                                "label '%Y' used but not defined", label->base.symbol);
4789                  }
4790         }
4791
4792         if (warning.unused_label) {
4793                 for (const label_statement_t *label_statement = label_first;
4794                          label_statement != NULL;
4795                          label_statement = label_statement->next) {
4796                         label_t *label = label_statement->label;
4797
4798                         if (! label->used) {
4799                                 print_in_function();
4800                                 warningf(&label_statement->base.source_position,
4801                                          "label '%Y' defined but not used", label->base.symbol);
4802                         }
4803                 }
4804         }
4805 }
4806
4807 static void warn_unused_entity(entity_t *entity, entity_t *last)
4808 {
4809         entity_t const *const end = last != NULL ? last->base.next : NULL;
4810         for (; entity != end; entity = entity->base.next) {
4811                 if (!is_declaration(entity))
4812                         continue;
4813
4814                 declaration_t *declaration = &entity->declaration;
4815                 if (declaration->implicit)
4816                         continue;
4817
4818                 if (!declaration->used) {
4819                         print_in_function();
4820                         const char *what = get_entity_kind_name(entity->kind);
4821                         warningf(&entity->base.source_position, "%s '%Y' is unused",
4822                                  what, entity->base.symbol);
4823                 } else if (entity->kind == ENTITY_VARIABLE && !entity->variable.read) {
4824                         print_in_function();
4825                         const char *what = get_entity_kind_name(entity->kind);
4826                         warningf(&entity->base.source_position, "%s '%Y' is never read",
4827                                  what, entity->base.symbol);
4828                 }
4829         }
4830 }
4831
4832 static void check_unused_variables(statement_t *const stmt, void *const env)
4833 {
4834         (void)env;
4835
4836         switch (stmt->kind) {
4837                 case STATEMENT_DECLARATION: {
4838                         declaration_statement_t const *const decls = &stmt->declaration;
4839                         warn_unused_entity(decls->declarations_begin,
4840                                            decls->declarations_end);
4841                         return;
4842                 }
4843
4844                 case STATEMENT_FOR:
4845                         warn_unused_entity(stmt->fors.scope.entities, NULL);
4846                         return;
4847
4848                 default:
4849                         return;
4850         }
4851 }
4852
4853 /**
4854  * Check declarations of current_function for unused entities.
4855  */
4856 static void check_declarations(void)
4857 {
4858         if (warning.unused_parameter) {
4859                 const scope_t *scope = &current_function->parameters;
4860
4861                 /* do not issue unused warnings for main */
4862                 if (!is_sym_main(current_function->base.base.symbol)) {
4863                         warn_unused_entity(scope->entities, NULL);
4864                 }
4865         }
4866         if (warning.unused_variable) {
4867                 walk_statements(current_function->statement, check_unused_variables,
4868                                 NULL);
4869         }
4870 }
4871
4872 static int determine_truth(expression_t const* const cond)
4873 {
4874         return
4875                 !is_constant_expression(cond) ? 0 :
4876                 fold_constant_to_bool(cond)   ? 1 :
4877                 -1;
4878 }
4879
4880 static void check_reachable(statement_t *);
4881 static bool reaches_end;
4882
4883 static bool expression_returns(expression_t const *const expr)
4884 {
4885         switch (expr->kind) {
4886                 case EXPR_CALL: {
4887                         expression_t const *const func = expr->call.function;
4888                         if (func->kind == EXPR_REFERENCE) {
4889                                 entity_t *entity = func->reference.entity;
4890                                 if (entity->kind == ENTITY_FUNCTION
4891                                                 && entity->declaration.modifiers & DM_NORETURN)
4892                                         return false;
4893                         }
4894
4895                         if (!expression_returns(func))
4896                                 return false;
4897
4898                         for (call_argument_t const* arg = expr->call.arguments; arg != NULL; arg = arg->next) {
4899                                 if (!expression_returns(arg->expression))
4900                                         return false;
4901                         }
4902
4903                         return true;
4904                 }
4905
4906                 case EXPR_REFERENCE:
4907                 case EXPR_REFERENCE_ENUM_VALUE:
4908                 EXPR_LITERAL_CASES
4909                 case EXPR_STRING_LITERAL:
4910                 case EXPR_WIDE_STRING_LITERAL:
4911                 case EXPR_COMPOUND_LITERAL: // TODO descend into initialisers
4912                 case EXPR_LABEL_ADDRESS:
4913                 case EXPR_CLASSIFY_TYPE:
4914                 case EXPR_SIZEOF: // TODO handle obscure VLA case
4915                 case EXPR_ALIGNOF:
4916                 case EXPR_FUNCNAME:
4917                 case EXPR_BUILTIN_CONSTANT_P:
4918                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P:
4919                 case EXPR_OFFSETOF:
4920                 case EXPR_INVALID:
4921                         return true;
4922
4923                 case EXPR_STATEMENT: {
4924                         bool old_reaches_end = reaches_end;
4925                         reaches_end = false;
4926                         check_reachable(expr->statement.statement);
4927                         bool returns = reaches_end;
4928                         reaches_end = old_reaches_end;
4929                         return returns;
4930                 }
4931
4932                 case EXPR_CONDITIONAL:
4933                         // TODO handle constant expression
4934
4935                         if (!expression_returns(expr->conditional.condition))
4936                                 return false;
4937
4938                         if (expr->conditional.true_expression != NULL
4939                                         && expression_returns(expr->conditional.true_expression))
4940                                 return true;
4941
4942                         return expression_returns(expr->conditional.false_expression);
4943
4944                 case EXPR_SELECT:
4945                         return expression_returns(expr->select.compound);
4946
4947                 case EXPR_ARRAY_ACCESS:
4948                         return
4949                                 expression_returns(expr->array_access.array_ref) &&
4950                                 expression_returns(expr->array_access.index);
4951
4952                 case EXPR_VA_START:
4953                         return expression_returns(expr->va_starte.ap);
4954
4955                 case EXPR_VA_ARG:
4956                         return expression_returns(expr->va_arge.ap);
4957
4958                 case EXPR_VA_COPY:
4959                         return expression_returns(expr->va_copye.src);
4960
4961                 EXPR_UNARY_CASES_MANDATORY
4962                         return expression_returns(expr->unary.value);
4963
4964                 case EXPR_UNARY_THROW:
4965                         return false;
4966
4967                 EXPR_BINARY_CASES
4968                         // TODO handle constant lhs of && and ||
4969                         return
4970                                 expression_returns(expr->binary.left) &&
4971                                 expression_returns(expr->binary.right);
4972
4973                 case EXPR_UNKNOWN:
4974                         break;
4975         }
4976
4977         panic("unhandled expression");
4978 }
4979
4980 static bool initializer_returns(initializer_t const *const init)
4981 {
4982         switch (init->kind) {
4983                 case INITIALIZER_VALUE:
4984                         return expression_returns(init->value.value);
4985
4986                 case INITIALIZER_LIST: {
4987                         initializer_t * const*       i       = init->list.initializers;
4988                         initializer_t * const* const end     = i + init->list.len;
4989                         bool                         returns = true;
4990                         for (; i != end; ++i) {
4991                                 if (!initializer_returns(*i))
4992                                         returns = false;
4993                         }
4994                         return returns;
4995                 }
4996
4997                 case INITIALIZER_STRING:
4998                 case INITIALIZER_WIDE_STRING:
4999                 case INITIALIZER_DESIGNATOR: // designators have no payload
5000                         return true;
5001         }
5002         panic("unhandled initializer");
5003 }
5004
5005 static bool noreturn_candidate;
5006
5007 static void check_reachable(statement_t *const stmt)
5008 {
5009         if (stmt->base.reachable)
5010                 return;
5011         if (stmt->kind != STATEMENT_DO_WHILE)
5012                 stmt->base.reachable = true;
5013
5014         statement_t *last = stmt;
5015         statement_t *next;
5016         switch (stmt->kind) {
5017                 case STATEMENT_INVALID:
5018                 case STATEMENT_EMPTY:
5019                 case STATEMENT_ASM:
5020                         next = stmt->base.next;
5021                         break;
5022
5023                 case STATEMENT_DECLARATION: {
5024                         declaration_statement_t const *const decl = &stmt->declaration;
5025                         entity_t                const *      ent  = decl->declarations_begin;
5026                         entity_t                const *const last = decl->declarations_end;
5027                         if (ent != NULL) {
5028                                 for (;; ent = ent->base.next) {
5029                                         if (ent->kind                 == ENTITY_VARIABLE &&
5030                                                         ent->variable.initializer != NULL            &&
5031                                                         !initializer_returns(ent->variable.initializer)) {
5032                                                 return;
5033                                         }
5034                                         if (ent == last)
5035                                                 break;
5036                                 }
5037                         }
5038                         next = stmt->base.next;
5039                         break;
5040                 }
5041
5042                 case STATEMENT_COMPOUND:
5043                         next = stmt->compound.statements;
5044                         if (next == NULL)
5045                                 next = stmt->base.next;
5046                         break;
5047
5048                 case STATEMENT_RETURN: {
5049                         expression_t const *const val = stmt->returns.value;
5050                         if (val == NULL || expression_returns(val))
5051                                 noreturn_candidate = false;
5052                         return;
5053                 }
5054
5055                 case STATEMENT_IF: {
5056                         if_statement_t const *const ifs  = &stmt->ifs;
5057                         expression_t   const *const cond = ifs->condition;
5058
5059                         if (!expression_returns(cond))
5060                                 return;
5061
5062                         int const val = determine_truth(cond);
5063
5064                         if (val >= 0)
5065                                 check_reachable(ifs->true_statement);
5066
5067                         if (val > 0)
5068                                 return;
5069
5070                         if (ifs->false_statement != NULL) {
5071                                 check_reachable(ifs->false_statement);
5072                                 return;
5073                         }
5074
5075                         next = stmt->base.next;
5076                         break;
5077                 }
5078
5079                 case STATEMENT_SWITCH: {
5080                         switch_statement_t const *const switchs = &stmt->switchs;
5081                         expression_t       const *const expr    = switchs->expression;
5082
5083                         if (!expression_returns(expr))
5084                                 return;
5085
5086                         if (is_constant_expression(expr)) {
5087                                 long                    const val      = fold_constant_to_int(expr);
5088                                 case_label_statement_t *      defaults = NULL;
5089                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5090                                         if (i->expression == NULL) {
5091                                                 defaults = i;
5092                                                 continue;
5093                                         }
5094
5095                                         if (i->first_case <= val && val <= i->last_case) {
5096                                                 check_reachable((statement_t*)i);
5097                                                 return;
5098                                         }
5099                                 }
5100
5101                                 if (defaults != NULL) {
5102                                         check_reachable((statement_t*)defaults);
5103                                         return;
5104                                 }
5105                         } else {
5106                                 bool has_default = false;
5107                                 for (case_label_statement_t *i = switchs->first_case; i != NULL; i = i->next) {
5108                                         if (i->expression == NULL)
5109                                                 has_default = true;
5110
5111                                         check_reachable((statement_t*)i);
5112                                 }
5113
5114                                 if (has_default)
5115                                         return;
5116                         }
5117
5118                         next = stmt->base.next;
5119                         break;
5120                 }
5121
5122                 case STATEMENT_EXPRESSION: {
5123                         /* Check for noreturn function call */
5124                         expression_t const *const expr = stmt->expression.expression;
5125                         if (!expression_returns(expr))
5126                                 return;
5127
5128                         next = stmt->base.next;
5129                         break;
5130                 }
5131
5132                 case STATEMENT_CONTINUE:
5133                         for (statement_t *parent = stmt;;) {
5134                                 parent = parent->base.parent;
5135                                 if (parent == NULL) /* continue not within loop */
5136                                         return;
5137
5138                                 next = parent;
5139                                 switch (parent->kind) {
5140                                         case STATEMENT_WHILE:    goto continue_while;
5141                                         case STATEMENT_DO_WHILE: goto continue_do_while;
5142                                         case STATEMENT_FOR:      goto continue_for;
5143
5144                                         default: break;
5145                                 }
5146                         }
5147
5148                 case STATEMENT_BREAK:
5149                         for (statement_t *parent = stmt;;) {
5150                                 parent = parent->base.parent;
5151                                 if (parent == NULL) /* break not within loop/switch */
5152                                         return;
5153
5154                                 switch (parent->kind) {
5155                                         case STATEMENT_SWITCH:
5156                                         case STATEMENT_WHILE:
5157                                         case STATEMENT_DO_WHILE:
5158                                         case STATEMENT_FOR:
5159                                                 last = parent;
5160                                                 next = parent->base.next;
5161                                                 goto found_break_parent;
5162
5163                                         default: break;
5164                                 }
5165                         }
5166 found_break_parent:
5167                         break;
5168
5169                 case STATEMENT_GOTO:
5170                         if (stmt->gotos.expression) {
5171                                 if (!expression_returns(stmt->gotos.expression))
5172                                         return;
5173
5174                                 statement_t *parent = stmt->base.parent;
5175                                 if (parent == NULL) /* top level goto */
5176                                         return;
5177                                 next = parent;
5178                         } else {
5179                                 next = stmt->gotos.label->statement;
5180                                 if (next == NULL) /* missing label */
5181                                         return;
5182                         }
5183                         break;
5184
5185                 case STATEMENT_LABEL:
5186                         next = stmt->label.statement;
5187                         break;
5188
5189                 case STATEMENT_CASE_LABEL:
5190                         next = stmt->case_label.statement;
5191                         break;
5192
5193                 case STATEMENT_WHILE: {
5194                         while_statement_t const *const whiles = &stmt->whiles;
5195                         expression_t      const *const cond   = whiles->condition;
5196
5197                         if (!expression_returns(cond))
5198                                 return;
5199
5200                         int const val = determine_truth(cond);
5201
5202                         if (val >= 0)
5203                                 check_reachable(whiles->body);
5204
5205                         if (val > 0)
5206                                 return;
5207
5208                         next = stmt->base.next;
5209                         break;
5210                 }
5211
5212                 case STATEMENT_DO_WHILE:
5213                         next = stmt->do_while.body;
5214                         break;
5215
5216                 case STATEMENT_FOR: {
5217                         for_statement_t *const fors = &stmt->fors;
5218
5219                         if (fors->condition_reachable)
5220                                 return;
5221                         fors->condition_reachable = true;
5222
5223                         expression_t const *const cond = fors->condition;
5224
5225                         int val;
5226                         if (cond == NULL) {
5227                                 val = 1;
5228                         } else if (expression_returns(cond)) {
5229                                 val = determine_truth(cond);
5230                         } else {
5231                                 return;
5232                         }
5233
5234                         if (val >= 0)
5235                                 check_reachable(fors->body);
5236
5237                         if (val > 0)
5238                                 return;
5239
5240                         next = stmt->base.next;
5241                         break;
5242                 }
5243
5244                 case STATEMENT_MS_TRY: {
5245                         ms_try_statement_t const *const ms_try = &stmt->ms_try;
5246                         check_reachable(ms_try->try_statement);
5247                         next = ms_try->final_statement;
5248                         break;
5249                 }
5250
5251                 case STATEMENT_LEAVE: {
5252                         statement_t *parent = stmt;
5253                         for (;;) {
5254                                 parent = parent->base.parent;
5255                                 if (parent == NULL) /* __leave not within __try */
5256                                         return;
5257
5258                                 if (parent->kind == STATEMENT_MS_TRY) {
5259                                         last = parent;
5260                                         next = parent->ms_try.final_statement;
5261                                         break;
5262                                 }
5263                         }
5264                         break;
5265                 }
5266
5267                 default:
5268                         panic("invalid statement kind");
5269         }
5270
5271         while (next == NULL) {
5272                 next = last->base.parent;
5273                 if (next == NULL) {
5274                         noreturn_candidate = false;
5275
5276                         type_t *const type = skip_typeref(current_function->base.type);
5277                         assert(is_type_function(type));
5278                         type_t *const ret  = skip_typeref(type->function.return_type);
5279                         if (warning.return_type                    &&
5280                             !is_type_atomic(ret, ATOMIC_TYPE_VOID) &&
5281                             is_type_valid(ret)                     &&
5282                             !is_sym_main(current_function->base.base.symbol)) {
5283                                 warningf(&stmt->base.source_position,
5284                                          "control reaches end of non-void function");
5285                         }
5286                         return;
5287                 }
5288
5289                 switch (next->kind) {
5290                         case STATEMENT_INVALID:
5291                         case STATEMENT_EMPTY:
5292                         case STATEMENT_DECLARATION:
5293                         case STATEMENT_EXPRESSION:
5294                         case STATEMENT_ASM:
5295                         case STATEMENT_RETURN:
5296                         case STATEMENT_CONTINUE:
5297                         case STATEMENT_BREAK:
5298                         case STATEMENT_GOTO:
5299                         case STATEMENT_LEAVE:
5300                                 panic("invalid control flow in function");
5301
5302                         case STATEMENT_COMPOUND:
5303                                 if (next->compound.stmt_expr) {
5304                                         reaches_end = true;
5305                                         return;
5306                                 }
5307                                 /* FALLTHROUGH */
5308                         case STATEMENT_IF:
5309                         case STATEMENT_SWITCH:
5310                         case STATEMENT_LABEL:
5311                         case STATEMENT_CASE_LABEL:
5312                                 last = next;
5313                                 next = next->base.next;
5314                                 break;
5315
5316                         case STATEMENT_WHILE: {
5317 continue_while:
5318                                 if (next->base.reachable)
5319                                         return;
5320                                 next->base.reachable = true;
5321
5322                                 while_statement_t const *const whiles = &next->whiles;
5323                                 expression_t      const *const cond   = whiles->condition;
5324
5325                                 if (!expression_returns(cond))
5326                                         return;
5327
5328                                 int const val = determine_truth(cond);
5329
5330                                 if (val >= 0)
5331                                         check_reachable(whiles->body);
5332
5333                                 if (val > 0)
5334                                         return;
5335
5336                                 last = next;
5337                                 next = next->base.next;
5338                                 break;
5339                         }
5340
5341                         case STATEMENT_DO_WHILE: {
5342 continue_do_while:
5343                                 if (next->base.reachable)
5344                                         return;
5345                                 next->base.reachable = true;
5346
5347                                 do_while_statement_t const *const dw   = &next->do_while;
5348                                 expression_t         const *const cond = dw->condition;
5349
5350                                 if (!expression_returns(cond))
5351                                         return;
5352
5353                                 int const val = determine_truth(cond);
5354
5355                                 if (val >= 0)
5356                                         check_reachable(dw->body);
5357
5358                                 if (val > 0)
5359                                         return;
5360
5361                                 last = next;
5362                                 next = next->base.next;
5363                                 break;
5364                         }
5365
5366                         case STATEMENT_FOR: {
5367 continue_for:;
5368                                 for_statement_t *const fors = &next->fors;
5369
5370                                 fors->step_reachable = true;
5371
5372                                 if (fors->condition_reachable)
5373                                         return;
5374                                 fors->condition_reachable = true;
5375
5376                                 expression_t const *const cond = fors->condition;
5377
5378                                 int val;
5379                                 if (cond == NULL) {
5380                                         val = 1;
5381                                 } else if (expression_returns(cond)) {
5382                                         val = determine_truth(cond);
5383                                 } else {
5384                                         return;
5385                                 }
5386
5387                                 if (val >= 0)
5388                                         check_reachable(fors->body);
5389
5390                                 if (val > 0)
5391                                         return;
5392
5393                                 last = next;
5394                                 next = next->base.next;
5395                                 break;
5396                         }
5397
5398                         case STATEMENT_MS_TRY:
5399                                 last = next;
5400                                 next = next->ms_try.final_statement;
5401                                 break;
5402                 }
5403         }
5404
5405         check_reachable(next);
5406 }
5407
5408 static void check_unreachable(statement_t* const stmt, void *const env)
5409 {
5410         (void)env;
5411
5412         switch (stmt->kind) {
5413                 case STATEMENT_DO_WHILE:
5414                         if (!stmt->base.reachable) {
5415                                 expression_t const *const cond = stmt->do_while.condition;
5416                                 if (determine_truth(cond) >= 0) {
5417                                         warningf(&cond->base.source_position,
5418                                                  "condition of do-while-loop is unreachable");
5419                                 }
5420                         }
5421                         return;
5422
5423                 case STATEMENT_FOR: {
5424                         for_statement_t const* const fors = &stmt->fors;
5425
5426                         // if init and step are unreachable, cond is unreachable, too
5427                         if (!stmt->base.reachable && !fors->step_reachable) {
5428                                 warningf(&stmt->base.source_position, "statement is unreachable");
5429                         } else {
5430                                 if (!stmt->base.reachable && fors->initialisation != NULL) {
5431                                         warningf(&fors->initialisation->base.source_position,
5432                                                  "initialisation of for-statement is unreachable");
5433                                 }
5434
5435                                 if (!fors->condition_reachable && fors->condition != NULL) {
5436                                         warningf(&fors->condition->base.source_position,
5437                                                  "condition of for-statement is unreachable");
5438                                 }
5439
5440                                 if (!fors->step_reachable && fors->step != NULL) {
5441                                         warningf(&fors->step->base.source_position,
5442                                                  "step of for-statement is unreachable");
5443                                 }
5444                         }
5445                         return;
5446                 }
5447
5448                 case STATEMENT_COMPOUND:
5449                         if (stmt->compound.statements != NULL)
5450                                 return;
5451                         goto warn_unreachable;
5452
5453                 case STATEMENT_DECLARATION: {
5454                         /* Only warn if there is at least one declarator with an initializer.
5455                          * This typically occurs in switch statements. */
5456                         declaration_statement_t const *const decl = &stmt->declaration;
5457                         entity_t                const *      ent  = decl->declarations_begin;
5458                         entity_t                const *const last = decl->declarations_end;
5459                         if (ent != NULL) {
5460                                 for (;; ent = ent->base.next) {
5461                                         if (ent->kind                 == ENTITY_VARIABLE &&
5462                                                         ent->variable.initializer != NULL) {
5463                                                 goto warn_unreachable;
5464                                         }
5465                                         if (ent == last)
5466                                                 return;
5467                                 }
5468                         }
5469                 }
5470
5471                 default:
5472 warn_unreachable:
5473                         if (!stmt->base.reachable)
5474                                 warningf(&stmt->base.source_position, "statement is unreachable");
5475                         return;
5476         }
5477 }
5478
5479 static void parse_external_declaration(void)
5480 {
5481         /* function-definitions and declarations both start with declaration
5482          * specifiers */
5483         declaration_specifiers_t specifiers;
5484         memset(&specifiers, 0, sizeof(specifiers));
5485
5486         add_anchor_token(';');
5487         parse_declaration_specifiers(&specifiers);
5488         rem_anchor_token(';');
5489
5490         /* must be a declaration */
5491         if (token.type == ';') {
5492                 parse_anonymous_declaration_rest(&specifiers);
5493                 return;
5494         }
5495
5496         add_anchor_token(',');
5497         add_anchor_token('=');
5498         add_anchor_token(';');
5499         add_anchor_token('{');
5500
5501         /* declarator is common to both function-definitions and declarations */
5502         entity_t *ndeclaration = parse_declarator(&specifiers, DECL_FLAGS_NONE);
5503
5504         rem_anchor_token('{');
5505         rem_anchor_token(';');
5506         rem_anchor_token('=');
5507         rem_anchor_token(',');
5508
5509         /* must be a declaration */
5510         switch (token.type) {
5511                 case ',':
5512                 case ';':
5513                 case '=':
5514                         parse_declaration_rest(ndeclaration, &specifiers, record_entity,
5515                                         DECL_FLAGS_NONE);
5516                         return;
5517         }
5518
5519         /* must be a function definition */
5520         parse_kr_declaration_list(ndeclaration);
5521
5522         if (token.type != '{') {
5523                 parse_error_expected("while parsing function definition", '{', NULL);
5524                 eat_until_matching_token(';');
5525                 return;
5526         }
5527
5528         assert(is_declaration(ndeclaration));
5529         type_t *const orig_type = ndeclaration->declaration.type;
5530         type_t *      type      = skip_typeref(orig_type);
5531
5532         if (!is_type_function(type)) {
5533                 if (is_type_valid(type)) {
5534                         errorf(HERE, "declarator '%#T' has a body but is not a function type",
5535                                type, ndeclaration->base.symbol);
5536                 }
5537                 eat_block();
5538                 return;
5539         } else if (is_typeref(orig_type)) {
5540                 /* §6.9.1:2 */
5541                 errorf(&ndeclaration->base.source_position,
5542                                 "type of function definition '%#T' is a typedef",
5543                                 orig_type, ndeclaration->base.symbol);
5544         }
5545
5546         if (warning.aggregate_return &&
5547             is_type_compound(skip_typeref(type->function.return_type))) {
5548                 warningf(HERE, "function '%Y' returns an aggregate",
5549                          ndeclaration->base.symbol);
5550         }
5551         if (warning.traditional && !type->function.unspecified_parameters) {
5552                 warningf(HERE, "traditional C rejects ISO C style function definition of function '%Y'",
5553                         ndeclaration->base.symbol);
5554         }
5555         if (warning.old_style_definition && type->function.unspecified_parameters) {
5556                 warningf(HERE, "old-style function definition '%Y'",
5557                         ndeclaration->base.symbol);
5558         }
5559
5560         /* §6.7.5.3:14 a function definition with () means no
5561          * parameters (and not unspecified parameters) */
5562         if (type->function.unspecified_parameters &&
5563                         type->function.parameters == NULL) {
5564                 type_t *copy                          = duplicate_type(type);
5565                 copy->function.unspecified_parameters = false;
5566                 type                                  = identify_new_type(copy);
5567
5568                 ndeclaration->declaration.type = type;
5569         }
5570
5571         entity_t *const entity = record_entity(ndeclaration, true);
5572         assert(entity->kind == ENTITY_FUNCTION);
5573         assert(ndeclaration->kind == ENTITY_FUNCTION);
5574
5575         function_t *function = &entity->function;
5576         if (ndeclaration != entity) {
5577                 function->parameters = ndeclaration->function.parameters;
5578         }
5579         assert(is_declaration(entity));
5580         type = skip_typeref(entity->declaration.type);
5581
5582         /* push function parameters and switch scope */
5583         size_t const  top       = environment_top();
5584         scope_t      *old_scope = scope_push(&function->parameters);
5585
5586         entity_t *parameter = function->parameters.entities;
5587         for (; parameter != NULL; parameter = parameter->base.next) {
5588                 if (parameter->base.parent_scope == &ndeclaration->function.parameters) {
5589                         parameter->base.parent_scope = current_scope;
5590                 }
5591                 assert(parameter->base.parent_scope == NULL
5592                                 || parameter->base.parent_scope == current_scope);
5593                 parameter->base.parent_scope = current_scope;
5594                 if (parameter->base.symbol == NULL) {
5595                         errorf(&parameter->base.source_position, "parameter name omitted");
5596                         continue;
5597                 }
5598                 environment_push(parameter);
5599         }
5600
5601         if (function->statement != NULL) {
5602                 parser_error_multiple_definition(entity, HERE);
5603                 eat_block();
5604         } else {
5605                 /* parse function body */
5606                 int         label_stack_top      = label_top();
5607                 function_t *old_current_function = current_function;
5608                 entity_t   *old_current_entity   = current_entity;
5609                 current_function                 = function;
5610                 current_entity                   = (entity_t*) function;
5611                 current_parent                   = NULL;
5612
5613                 goto_first   = NULL;
5614                 goto_anchor  = &goto_first;
5615                 label_first  = NULL;
5616                 label_anchor = &label_first;
5617
5618                 statement_t *const body = parse_compound_statement(false);
5619                 function->statement = body;
5620                 first_err = true;
5621                 check_labels();
5622                 check_declarations();
5623                 if (warning.return_type      ||
5624                     warning.unreachable_code ||
5625                     (warning.missing_noreturn
5626                      && !(function->base.modifiers & DM_NORETURN))) {
5627                         noreturn_candidate = true;
5628                         check_reachable(body);
5629                         if (warning.unreachable_code)
5630                                 walk_statements(body, check_unreachable, NULL);
5631                         if (warning.missing_noreturn &&
5632                             noreturn_candidate       &&
5633                             !(function->base.modifiers & DM_NORETURN)) {
5634                                 warningf(&body->base.source_position,
5635                                          "function '%#T' is candidate for attribute 'noreturn'",
5636                                          type, entity->base.symbol);
5637                         }
5638                 }
5639
5640                 assert(current_parent   == NULL);
5641                 assert(current_function == function);
5642                 assert(current_entity   == (entity_t*) function);
5643                 current_entity   = old_current_entity;
5644                 current_function = old_current_function;
5645                 label_pop_to(label_stack_top);
5646         }
5647
5648         assert(current_scope == &function->parameters);
5649         scope_pop(old_scope);
5650         environment_pop_to(top);
5651 }
5652
5653 static type_t *make_bitfield_type(type_t *base_type, expression_t *size,
5654                                   source_position_t *source_position,
5655                                   const symbol_t *symbol)
5656 {
5657         type_t *type = allocate_type_zero(TYPE_BITFIELD);
5658
5659         type->bitfield.base_type       = base_type;
5660         type->bitfield.size_expression = size;
5661
5662         il_size_t bit_size;
5663         type_t *skipped_type = skip_typeref(base_type);
5664         if (!is_type_integer(skipped_type)) {
5665                 errorf(HERE, "bitfield base type '%T' is not an integer type",
5666                        base_type);
5667                 bit_size = 0;
5668         } else {
5669                 bit_size = get_type_size(base_type) * 8;
5670         }
5671
5672         if (is_constant_expression(size)) {
5673                 long v = fold_constant_to_int(size);
5674                 const symbol_t *user_symbol = symbol == NULL ? sym_anonymous : symbol;
5675
5676                 if (v < 0) {
5677                         errorf(source_position, "negative width in bit-field '%Y'",
5678                                user_symbol);
5679                 } else if (v == 0 && symbol != NULL) {
5680                         errorf(source_position, "zero width for bit-field '%Y'",
5681                                user_symbol);
5682                 } else if (bit_size > 0 && (il_size_t)v > bit_size) {
5683                         errorf(source_position, "width of '%Y' exceeds its type",
5684                                user_symbol);
5685                 } else {
5686                         type->bitfield.bit_size = v;
5687                 }
5688         }
5689
5690         return type;
5691 }
5692
5693 static entity_t *find_compound_entry(compound_t *compound, symbol_t *symbol)
5694 {
5695         entity_t *iter = compound->members.entities;
5696         for (; iter != NULL; iter = iter->base.next) {
5697                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
5698                         continue;
5699
5700                 if (iter->base.symbol == symbol) {
5701                         return iter;
5702                 } else if (iter->base.symbol == NULL) {
5703                         /* search in anonymous structs and unions */
5704                         type_t *type = skip_typeref(iter->declaration.type);
5705                         if (is_type_compound(type)) {
5706                                 if (find_compound_entry(type->compound.compound, symbol)
5707                                                 != NULL)
5708                                         return iter;
5709                         }
5710                         continue;
5711                 }
5712         }
5713
5714         return NULL;
5715 }
5716
5717 static void check_deprecated(const source_position_t *source_position,
5718                              const entity_t *entity)
5719 {
5720         if (!warning.deprecated_declarations)
5721                 return;
5722         if (!is_declaration(entity))
5723                 return;
5724         if ((entity->declaration.modifiers & DM_DEPRECATED) == 0)
5725                 return;
5726
5727         char const *const prefix = get_entity_kind_name(entity->kind);
5728         const char *deprecated_string
5729                         = get_deprecated_string(entity->declaration.attributes);
5730         if (deprecated_string != NULL) {
5731                 warningf(source_position, "%s '%Y' is deprecated (declared %P): \"%s\"",
5732                                  prefix, entity->base.symbol, &entity->base.source_position,
5733                                  deprecated_string);
5734         } else {
5735                 warningf(source_position, "%s '%Y' is deprecated (declared %P)", prefix,
5736                                  entity->base.symbol, &entity->base.source_position);
5737         }
5738 }
5739
5740
5741 static expression_t *create_select(const source_position_t *pos,
5742                                    expression_t *addr,
5743                                    type_qualifiers_t qualifiers,
5744                                                                    entity_t *entry)
5745 {
5746         assert(entry->kind == ENTITY_COMPOUND_MEMBER);
5747
5748         check_deprecated(pos, entry);
5749
5750         expression_t *select          = allocate_expression_zero(EXPR_SELECT);
5751         select->select.compound       = addr;
5752         select->select.compound_entry = entry;
5753
5754         type_t *entry_type = entry->declaration.type;
5755         type_t *res_type   = get_qualified_type(entry_type, qualifiers);
5756
5757         /* we always do the auto-type conversions; the & and sizeof parser contains
5758          * code to revert this! */
5759         select->base.type = automatic_type_conversion(res_type);
5760         if (res_type->kind == TYPE_BITFIELD) {
5761                 select->base.type = res_type->bitfield.base_type;
5762         }
5763
5764         return select;
5765 }
5766
5767 /**
5768  * Find entry with symbol in compound. Search anonymous structs and unions and
5769  * creates implicit select expressions for them.
5770  * Returns the adress for the innermost compound.
5771  */
5772 static expression_t *find_create_select(const source_position_t *pos,
5773                                         expression_t *addr,
5774                                         type_qualifiers_t qualifiers,
5775                                         compound_t *compound, symbol_t *symbol)
5776 {
5777         entity_t *iter = compound->members.entities;
5778         for (; iter != NULL; iter = iter->base.next) {
5779                 if (iter->kind != ENTITY_COMPOUND_MEMBER)
5780                         continue;
5781
5782                 symbol_t *iter_symbol = iter->base.symbol;
5783                 if (iter_symbol == NULL) {
5784                         type_t *type = iter->declaration.type;
5785                         if (type->kind != TYPE_COMPOUND_STRUCT
5786                                         && type->kind != TYPE_COMPOUND_UNION)
5787                                 continue;
5788
5789                         compound_t *sub_compound = type->compound.compound;
5790
5791                         if (find_compound_entry(sub_compound, symbol) == NULL)
5792                                 continue;
5793
5794                         expression_t *sub_addr = create_select(pos, addr, qualifiers, iter);
5795                         sub_addr->base.source_position = *pos;
5796                         sub_addr->select.implicit      = true;
5797                         return find_create_select(pos, sub_addr, qualifiers, sub_compound,
5798                                                   symbol);
5799                 }
5800
5801                 if (iter_symbol == symbol) {
5802                         return create_select(pos, addr, qualifiers, iter);
5803                 }
5804         }
5805
5806         return NULL;
5807 }
5808
5809 static void parse_compound_declarators(compound_t *compound,
5810                 const declaration_specifiers_t *specifiers)
5811 {
5812         do {
5813                 entity_t *entity;
5814
5815                 if (token.type == ':') {
5816                         source_position_t source_position = *HERE;
5817                         next_token();
5818
5819                         type_t *base_type = specifiers->type;
5820                         expression_t *size = parse_constant_expression();
5821
5822                         type_t *type = make_bitfield_type(base_type, size,
5823                                         &source_position, NULL);
5824
5825                         attribute_t  *attributes = parse_attributes(NULL);
5826                         attribute_t **anchor     = &attributes;
5827                         while (*anchor != NULL)
5828                                 anchor = &(*anchor)->next;
5829                         *anchor = specifiers->attributes;
5830
5831                         entity = allocate_entity_zero(ENTITY_COMPOUND_MEMBER);
5832                         entity->base.namespc                       = NAMESPACE_NORMAL;
5833                         entity->base.source_position               = source_position;
5834                         entity->declaration.declared_storage_class = STORAGE_CLASS_NONE;
5835                         entity->declaration.storage_class          = STORAGE_CLASS_NONE;
5836                         entity->declaration.type                   = type;
5837                         entity->declaration.attributes             = attributes;
5838
5839                         if (attributes != NULL) {
5840                                 handle_entity_attributes(attributes, entity);
5841                         }
5842                         append_entity(&compound->members, entity);
5843                 } else {
5844                         entity = parse_declarator(specifiers,
5845                                         DECL_MAY_BE_ABSTRACT | DECL_CREATE_COMPOUND_MEMBER);
5846                         if (entity->kind == ENTITY_TYPEDEF) {
5847                                 errorf(&entity->base.source_position,
5848                                                 "typedef not allowed as compound member");
5849                         } else {
5850                                 assert(entity->kind == ENTITY_COMPOUND_MEMBER);
5851
5852                                 /* make sure we don't define a symbol multiple times */
5853                                 symbol_t *symbol = entity->base.symbol;
5854                                 if (symbol != NULL) {
5855                                         entity_t *prev = find_compound_entry(compound, symbol);
5856                                         if (prev != NULL) {
5857                                                 errorf(&entity->base.source_position,
5858                                                                 "multiple declarations of symbol '%Y' (declared %P)",
5859                                                                 symbol, &prev->base.source_position);
5860                                         }
5861                                 }
5862
5863                                 if (token.type == ':') {
5864                                         source_position_t source_position = *HERE;
5865                                         next_token();
5866                                         expression_t *size = parse_constant_expression();
5867
5868                                         type_t *type          = entity->declaration.type;
5869                                         type_t *bitfield_type = make_bitfield_type(type, size,
5870                                                         &source_position, entity->base.symbol);
5871
5872                                         attribute_t *attributes = parse_attributes(NULL);
5873                                         entity->declaration.type = bitfield_type;
5874                                         handle_entity_attributes(attributes, entity);
5875                                 } else {
5876                                         type_t *orig_type = entity->declaration.type;
5877                                         type_t *type      = skip_typeref(orig_type);
5878                                         if (is_type_function(type)) {
5879                                                 errorf(&entity->base.source_position,
5880                                                        "compound member '%Y' must not have function type '%T'",
5881                                                                 entity->base.symbol, orig_type);
5882                                         } else if (is_type_incomplete(type)) {
5883                                                 /* §6.7.2.1:16 flexible array member */
5884                                                 if (!is_type_array(type)       ||
5885                                                                 token.type          != ';' ||
5886                                                                 look_ahead(1)->type != '}') {
5887                                                         errorf(&entity->base.source_position,
5888                                                                "compound member '%Y' has incomplete type '%T'",
5889                                                                         entity->base.symbol, orig_type);
5890                                                 }
5891                                         }
5892                                 }
5893
5894                                 append_entity(&compound->members, entity);
5895                         }
5896                 }
5897         } while (next_if(','));
5898         expect(';', end_error);
5899
5900 end_error:
5901         anonymous_entity = NULL;
5902 }
5903
5904 static void parse_compound_type_entries(compound_t *compound)
5905 {
5906         eat('{');
5907         add_anchor_token('}');
5908
5909         while (token.type != '}') {
5910                 if (token.type == T_EOF) {
5911                         errorf(HERE, "EOF while parsing struct");
5912                         break;
5913                 }
5914                 declaration_specifiers_t specifiers;
5915                 memset(&specifiers, 0, sizeof(specifiers));
5916                 parse_declaration_specifiers(&specifiers);
5917
5918                 parse_compound_declarators(compound, &specifiers);
5919         }
5920         rem_anchor_token('}');
5921         next_token();
5922
5923         /* §6.7.2.1:7 */
5924         compound->complete = true;
5925 }
5926
5927 static type_t *parse_typename(void)
5928 {
5929         declaration_specifiers_t specifiers;
5930         memset(&specifiers, 0, sizeof(specifiers));
5931         parse_declaration_specifiers(&specifiers);
5932         if (specifiers.storage_class != STORAGE_CLASS_NONE
5933                         || specifiers.thread_local) {
5934                 /* TODO: improve error message, user does probably not know what a
5935                  * storage class is...
5936                  */
5937                 errorf(HERE, "typename must not have a storage class");
5938         }
5939
5940         type_t *result = parse_abstract_declarator(specifiers.type);
5941
5942         return result;
5943 }
5944
5945
5946
5947
5948 typedef expression_t* (*parse_expression_function)(void);
5949 typedef expression_t* (*parse_expression_infix_function)(expression_t *left);
5950
5951 typedef struct expression_parser_function_t expression_parser_function_t;
5952 struct expression_parser_function_t {
5953         parse_expression_function        parser;
5954         precedence_t                     infix_precedence;
5955         parse_expression_infix_function  infix_parser;
5956 };
5957
5958 expression_parser_function_t expression_parsers[T_LAST_TOKEN];
5959
5960 /**
5961  * Prints an error message if an expression was expected but not read
5962  */
5963 static expression_t *expected_expression_error(void)
5964 {
5965         /* skip the error message if the error token was read */
5966         if (token.type != T_ERROR) {
5967                 errorf(HERE, "expected expression, got token %K", &token);
5968         }
5969         next_token();
5970
5971         return create_invalid_expression();
5972 }
5973
5974 static type_t *get_string_type(void)
5975 {
5976         return warning.write_strings ? type_const_char_ptr : type_char_ptr;
5977 }
5978
5979 static type_t *get_wide_string_type(void)
5980 {
5981         return warning.write_strings ? type_const_wchar_t_ptr : type_wchar_t_ptr;
5982 }
5983
5984 /**
5985  * Parse a string constant.
5986  */
5987 static expression_t *parse_string_literal(void)
5988 {
5989         source_position_t begin   = token.source_position;
5990         string_t          res     = token.literal;
5991         bool              is_wide = (token.type == T_WIDE_STRING_LITERAL);
5992
5993         next_token();
5994         while (token.type == T_STRING_LITERAL
5995                         || token.type == T_WIDE_STRING_LITERAL) {
5996                 warn_string_concat(&token.source_position);
5997                 res = concat_strings(&res, &token.literal);
5998                 next_token();
5999                 is_wide |= token.type == T_WIDE_STRING_LITERAL;
6000         }
6001
6002         expression_t *literal;
6003         if (is_wide) {
6004                 literal = allocate_expression_zero(EXPR_WIDE_STRING_LITERAL);
6005                 literal->base.type = get_wide_string_type();
6006         } else {
6007                 literal = allocate_expression_zero(EXPR_STRING_LITERAL);
6008                 literal->base.type = get_string_type();
6009         }
6010         literal->base.source_position = begin;
6011         literal->literal.value        = res;
6012
6013         return literal;
6014 }
6015
6016 /**
6017  * Parse a boolean constant.
6018  */
6019 static expression_t *parse_boolean_literal(bool value)
6020 {
6021         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_BOOLEAN);
6022         literal->base.source_position = token.source_position;
6023         literal->base.type            = type_bool;
6024         literal->literal.value.begin  = value ? "true" : "false";
6025         literal->literal.value.size   = value ? 4 : 5;
6026
6027         next_token();
6028         return literal;
6029 }
6030
6031 static void warn_traditional_suffix(void)
6032 {
6033         if (!warning.traditional)
6034                 return;
6035         warningf(&token.source_position, "traditional C rejects the '%Y' suffix",
6036                  token.symbol);
6037 }
6038
6039 static void check_integer_suffix(void)
6040 {
6041         symbol_t *suffix = token.symbol;
6042         if (suffix == NULL)
6043                 return;
6044
6045         bool not_traditional = false;
6046         const char *c = suffix->string;
6047         if (*c == 'l' || *c == 'L') {
6048                 ++c;
6049                 if (*c == *(c-1)) {
6050                         not_traditional = true;
6051                         ++c;
6052                         if (*c == 'u' || *c == 'U') {
6053                                 ++c;
6054                         }
6055                 } else if (*c == 'u' || *c == 'U') {
6056                         not_traditional = true;
6057                         ++c;
6058                 }
6059         } else if (*c == 'u' || *c == 'U') {
6060                 not_traditional = true;
6061                 ++c;
6062                 if (*c == 'l' || *c == 'L') {
6063                         ++c;
6064                         if (*c == *(c-1)) {
6065                                 ++c;
6066                         }
6067                 }
6068         }
6069         if (*c != '\0') {
6070                 errorf(&token.source_position,
6071                        "invalid suffix '%s' on integer constant", suffix->string);
6072         } else if (not_traditional) {
6073                 warn_traditional_suffix();
6074         }
6075 }
6076
6077 static type_t *check_floatingpoint_suffix(void)
6078 {
6079         symbol_t *suffix = token.symbol;
6080         type_t   *type   = type_double;
6081         if (suffix == NULL)
6082                 return type;
6083
6084         bool not_traditional = false;
6085         const char *c = suffix->string;
6086         if (*c == 'f' || *c == 'F') {
6087                 ++c;
6088                 type = type_float;
6089         } else if (*c == 'l' || *c == 'L') {
6090                 ++c;
6091                 type = type_long_double;
6092         }
6093         if (*c != '\0') {
6094                 errorf(&token.source_position,
6095                        "invalid suffix '%s' on floatingpoint constant", suffix->string);
6096         } else if (not_traditional) {
6097                 warn_traditional_suffix();
6098         }
6099
6100         return type;
6101 }
6102
6103 /**
6104  * Parse an integer constant.
6105  */
6106 static expression_t *parse_number_literal(void)
6107 {
6108         expression_kind_t  kind;
6109         type_t            *type;
6110
6111         switch (token.type) {
6112         case T_INTEGER:
6113                 kind = EXPR_LITERAL_INTEGER;
6114                 check_integer_suffix();
6115                 type = type_int;
6116                 break;
6117         case T_INTEGER_OCTAL:
6118                 kind = EXPR_LITERAL_INTEGER_OCTAL;
6119                 check_integer_suffix();
6120                 type = type_int;
6121                 break;
6122         case T_INTEGER_HEXADECIMAL:
6123                 kind = EXPR_LITERAL_INTEGER_HEXADECIMAL;
6124                 check_integer_suffix();
6125                 type = type_int;
6126                 break;
6127         case T_FLOATINGPOINT:
6128                 kind = EXPR_LITERAL_FLOATINGPOINT;
6129                 type = check_floatingpoint_suffix();
6130                 break;
6131         case T_FLOATINGPOINT_HEXADECIMAL:
6132                 kind = EXPR_LITERAL_FLOATINGPOINT_HEXADECIMAL;
6133                 type = check_floatingpoint_suffix();
6134                 break;
6135         default:
6136                 panic("unexpected token type in parse_number_literal");
6137         }
6138
6139         expression_t *literal = allocate_expression_zero(kind);
6140         literal->base.source_position = token.source_position;
6141         literal->base.type            = type;
6142         literal->literal.value        = token.literal;
6143         literal->literal.suffix       = token.symbol;
6144         next_token();
6145
6146         /* integer type depends on the size of the number and the size
6147          * representable by the types. The backend/codegeneration has to determine
6148          * that
6149          */
6150         determine_literal_type(&literal->literal);
6151         return literal;
6152 }
6153
6154 /**
6155  * Parse a character constant.
6156  */
6157 static expression_t *parse_character_constant(void)
6158 {
6159         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_CHARACTER);
6160         literal->base.source_position = token.source_position;
6161         literal->base.type            = c_mode & _CXX ? type_char : type_int;
6162         literal->literal.value        = token.literal;
6163
6164         size_t len = literal->literal.value.size;
6165         if (len != 1) {
6166                 if (!GNU_MODE && !(c_mode & _C99)) {
6167                         errorf(HERE, "more than 1 character in character constant");
6168                 } else if (warning.multichar) {
6169                         literal->base.type = type_int;
6170                         warningf(HERE, "multi-character character constant");
6171                 }
6172         }
6173
6174         next_token();
6175         return literal;
6176 }
6177
6178 /**
6179  * Parse a wide character constant.
6180  */
6181 static expression_t *parse_wide_character_constant(void)
6182 {
6183         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_WIDE_CHARACTER);
6184         literal->base.source_position = token.source_position;
6185         literal->base.type            = type_int;
6186         literal->literal.value        = token.literal;
6187
6188         size_t len = wstrlen(&literal->literal.value);
6189         if (len != 1) {
6190                 warningf(HERE, "multi-character character constant");
6191         }
6192
6193         next_token();
6194         return literal;
6195 }
6196
6197 static entity_t *create_implicit_function(symbol_t *symbol,
6198                 const source_position_t *source_position)
6199 {
6200         type_t *ntype                          = allocate_type_zero(TYPE_FUNCTION);
6201         ntype->function.return_type            = type_int;
6202         ntype->function.unspecified_parameters = true;
6203         ntype->function.linkage                = LINKAGE_C;
6204         type_t *type                           = identify_new_type(ntype);
6205
6206         entity_t *entity = allocate_entity_zero(ENTITY_FUNCTION);
6207         entity->declaration.storage_class          = STORAGE_CLASS_EXTERN;
6208         entity->declaration.declared_storage_class = STORAGE_CLASS_EXTERN;
6209         entity->declaration.type                   = type;
6210         entity->declaration.implicit               = true;
6211         entity->base.symbol                        = symbol;
6212         entity->base.source_position               = *source_position;
6213
6214         if (current_scope != NULL) {
6215                 bool strict_prototypes_old = warning.strict_prototypes;
6216                 warning.strict_prototypes  = false;
6217                 record_entity(entity, false);
6218                 warning.strict_prototypes = strict_prototypes_old;
6219         }
6220
6221         return entity;
6222 }
6223
6224 /**
6225  * Performs automatic type cast as described in §6.3.2.1.
6226  *
6227  * @param orig_type  the original type
6228  */
6229 static type_t *automatic_type_conversion(type_t *orig_type)
6230 {
6231         type_t *type = skip_typeref(orig_type);
6232         if (is_type_array(type)) {
6233                 array_type_t *array_type   = &type->array;
6234                 type_t       *element_type = array_type->element_type;
6235                 unsigned      qualifiers   = array_type->base.qualifiers;
6236
6237                 return make_pointer_type(element_type, qualifiers);
6238         }
6239
6240         if (is_type_function(type)) {
6241                 return make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
6242         }
6243
6244         return orig_type;
6245 }
6246
6247 /**
6248  * reverts the automatic casts of array to pointer types and function
6249  * to function-pointer types as defined §6.3.2.1
6250  */
6251 type_t *revert_automatic_type_conversion(const expression_t *expression)
6252 {
6253         switch (expression->kind) {
6254         case EXPR_REFERENCE: {
6255                 entity_t *entity = expression->reference.entity;
6256                 if (is_declaration(entity)) {
6257                         return entity->declaration.type;
6258                 } else if (entity->kind == ENTITY_ENUM_VALUE) {
6259                         return entity->enum_value.enum_type;
6260                 } else {
6261                         panic("no declaration or enum in reference");
6262                 }
6263         }
6264
6265         case EXPR_SELECT: {
6266                 entity_t *entity = expression->select.compound_entry;
6267                 assert(is_declaration(entity));
6268                 type_t   *type   = entity->declaration.type;
6269                 return get_qualified_type(type,
6270                                 expression->base.type->base.qualifiers);
6271         }
6272
6273         case EXPR_UNARY_DEREFERENCE: {
6274                 const expression_t *const value = expression->unary.value;
6275                 type_t             *const type  = skip_typeref(value->base.type);
6276                 if (!is_type_pointer(type))
6277                         return type_error_type;
6278                 return type->pointer.points_to;
6279         }
6280
6281         case EXPR_ARRAY_ACCESS: {
6282                 const expression_t *array_ref = expression->array_access.array_ref;
6283                 type_t             *type_left = skip_typeref(array_ref->base.type);
6284                 if (!is_type_pointer(type_left))
6285                         return type_error_type;
6286                 return type_left->pointer.points_to;
6287         }
6288
6289         case EXPR_STRING_LITERAL: {
6290                 size_t size = expression->string_literal.value.size;
6291                 return make_array_type(type_char, size, TYPE_QUALIFIER_NONE);
6292         }
6293
6294         case EXPR_WIDE_STRING_LITERAL: {
6295                 size_t size = wstrlen(&expression->string_literal.value);
6296                 return make_array_type(type_wchar_t, size, TYPE_QUALIFIER_NONE);
6297         }
6298
6299         case EXPR_COMPOUND_LITERAL:
6300                 return expression->compound_literal.type;
6301
6302         default:
6303                 break;
6304         }
6305         return expression->base.type;
6306 }
6307
6308 /**
6309  * Find an entity matching a symbol in a scope.
6310  * Uses current scope if scope is NULL
6311  */
6312 static entity_t *lookup_entity(const scope_t *scope, symbol_t *symbol,
6313                                namespace_tag_t namespc)
6314 {
6315         if (scope == NULL) {
6316                 return get_entity(symbol, namespc);
6317         }
6318
6319         /* we should optimize here, if scope grows above a certain size we should
6320            construct a hashmap here... */
6321         entity_t *entity = scope->entities;
6322         for ( ; entity != NULL; entity = entity->base.next) {
6323                 if (entity->base.symbol == symbol && entity->base.namespc == namespc)
6324                         break;
6325         }
6326
6327         return entity;
6328 }
6329
6330 static entity_t *parse_qualified_identifier(void)
6331 {
6332         /* namespace containing the symbol */
6333         symbol_t          *symbol;
6334         source_position_t  pos;
6335         const scope_t     *lookup_scope = NULL;
6336
6337         if (next_if(T_COLONCOLON))
6338                 lookup_scope = &unit->scope;
6339
6340         entity_t *entity;
6341         while (true) {
6342                 if (token.type != T_IDENTIFIER) {
6343                         parse_error_expected("while parsing identifier", T_IDENTIFIER, NULL);
6344                         return create_error_entity(sym_anonymous, ENTITY_VARIABLE);
6345                 }
6346                 symbol = token.symbol;
6347                 pos    = *HERE;
6348                 next_token();
6349
6350                 /* lookup entity */
6351                 entity = lookup_entity(lookup_scope, symbol, NAMESPACE_NORMAL);
6352
6353                 if (!next_if(T_COLONCOLON))
6354                         break;
6355
6356                 switch (entity->kind) {
6357                 case ENTITY_NAMESPACE:
6358                         lookup_scope = &entity->namespacee.members;
6359                         break;
6360                 case ENTITY_STRUCT:
6361                 case ENTITY_UNION:
6362                 case ENTITY_CLASS:
6363                         lookup_scope = &entity->compound.members;
6364                         break;
6365                 default:
6366                         errorf(&pos, "'%Y' must be a namespace, class, struct or union (but is a %s)",
6367                                symbol, get_entity_kind_name(entity->kind));
6368                         goto end_error;
6369                 }
6370         }
6371
6372         if (entity == NULL) {
6373                 if (!strict_mode && token.type == '(') {
6374                         /* an implicitly declared function */
6375                         if (warning.error_implicit_function_declaration) {
6376                                 errorf(&pos, "implicit declaration of function '%Y'", symbol);
6377                         } else if (warning.implicit_function_declaration) {
6378                                 warningf(&pos, "implicit declaration of function '%Y'", symbol);
6379                         }
6380
6381                         entity = create_implicit_function(symbol, &pos);
6382                 } else {
6383                         errorf(&pos, "unknown identifier '%Y' found.", symbol);
6384                         entity = create_error_entity(symbol, ENTITY_VARIABLE);
6385                 }
6386         }
6387
6388         return entity;
6389
6390 end_error:
6391         /* skip further qualifications */
6392         while (next_if(T_IDENTIFIER) && next_if(T_COLONCOLON)) {}
6393
6394         return create_error_entity(sym_anonymous, ENTITY_VARIABLE);
6395 }
6396
6397 static expression_t *parse_reference(void)
6398 {
6399         entity_t *entity = parse_qualified_identifier();
6400
6401         type_t *orig_type;
6402         if (is_declaration(entity)) {
6403                 orig_type = entity->declaration.type;
6404         } else if (entity->kind == ENTITY_ENUM_VALUE) {
6405                 orig_type = entity->enum_value.enum_type;
6406         } else {
6407                 panic("expected declaration or enum value in reference");
6408         }
6409
6410         /* we always do the auto-type conversions; the & and sizeof parser contains
6411          * code to revert this! */
6412         type_t *type = automatic_type_conversion(orig_type);
6413
6414         expression_kind_t kind = EXPR_REFERENCE;
6415         if (entity->kind == ENTITY_ENUM_VALUE)
6416                 kind = EXPR_REFERENCE_ENUM_VALUE;
6417
6418         expression_t *expression     = allocate_expression_zero(kind);
6419         expression->reference.entity = entity;
6420         expression->base.type        = type;
6421
6422         /* this declaration is used */
6423         if (is_declaration(entity)) {
6424                 entity->declaration.used = true;
6425         }
6426
6427         if (entity->base.parent_scope != file_scope
6428                 && (current_function != NULL
6429                         && entity->base.parent_scope->depth < current_function->parameters.depth)
6430                 && (entity->kind == ENTITY_VARIABLE || entity->kind == ENTITY_PARAMETER)) {
6431                 if (entity->kind == ENTITY_VARIABLE) {
6432                         /* access of a variable from an outer function */
6433                         entity->variable.address_taken = true;
6434                 } else if (entity->kind == ENTITY_PARAMETER) {
6435                         entity->parameter.address_taken = true;
6436                 }
6437                 current_function->need_closure = true;
6438         }
6439
6440         check_deprecated(HERE, entity);
6441
6442         if (warning.init_self && entity == current_init_decl && !in_type_prop
6443             && entity->kind == ENTITY_VARIABLE) {
6444                 current_init_decl = NULL;
6445                 warningf(HERE, "variable '%#T' is initialized by itself",
6446                          entity->declaration.type, entity->base.symbol);
6447         }
6448
6449         return expression;
6450 }
6451
6452 static bool semantic_cast(expression_t *cast)
6453 {
6454         expression_t            *expression      = cast->unary.value;
6455         type_t                  *orig_dest_type  = cast->base.type;
6456         type_t                  *orig_type_right = expression->base.type;
6457         type_t            const *dst_type        = skip_typeref(orig_dest_type);
6458         type_t            const *src_type        = skip_typeref(orig_type_right);
6459         source_position_t const *pos             = &cast->base.source_position;
6460
6461         /* §6.5.4 A (void) cast is explicitly permitted, more for documentation than for utility. */
6462         if (dst_type == type_void)
6463                 return true;
6464
6465         /* only integer and pointer can be casted to pointer */
6466         if (is_type_pointer(dst_type)  &&
6467             !is_type_pointer(src_type) &&
6468             !is_type_integer(src_type) &&
6469             is_type_valid(src_type)) {
6470                 errorf(pos, "cannot convert type '%T' to a pointer type", orig_type_right);
6471                 return false;
6472         }
6473
6474         if (!is_type_scalar(dst_type) && is_type_valid(dst_type)) {
6475                 errorf(pos, "conversion to non-scalar type '%T' requested", orig_dest_type);
6476                 return false;
6477         }
6478
6479         if (!is_type_scalar(src_type) && is_type_valid(src_type)) {
6480                 errorf(pos, "conversion from non-scalar type '%T' requested", orig_type_right);
6481                 return false;
6482         }
6483
6484         if (warning.cast_qual &&
6485             is_type_pointer(src_type) &&
6486             is_type_pointer(dst_type)) {
6487                 type_t *src = skip_typeref(src_type->pointer.points_to);
6488                 type_t *dst = skip_typeref(dst_type->pointer.points_to);
6489                 unsigned missing_qualifiers =
6490                         src->base.qualifiers & ~dst->base.qualifiers;
6491                 if (missing_qualifiers != 0) {
6492                         warningf(pos,
6493                                  "cast discards qualifiers '%Q' in pointer target type of '%T'",
6494                                  missing_qualifiers, orig_type_right);
6495                 }
6496         }
6497         return true;
6498 }
6499
6500 static expression_t *parse_compound_literal(type_t *type)
6501 {
6502         expression_t *expression = allocate_expression_zero(EXPR_COMPOUND_LITERAL);
6503
6504         parse_initializer_env_t env;
6505         env.type             = type;
6506         env.entity           = NULL;
6507         env.must_be_constant = false;
6508         initializer_t *initializer = parse_initializer(&env);
6509         type = env.type;
6510
6511         expression->compound_literal.initializer = initializer;
6512         expression->compound_literal.type        = type;
6513         expression->base.type                    = automatic_type_conversion(type);
6514
6515         return expression;
6516 }
6517
6518 /**
6519  * Parse a cast expression.
6520  */
6521 static expression_t *parse_cast(void)
6522 {
6523         add_anchor_token(')');
6524
6525         source_position_t source_position = token.source_position;
6526
6527         type_t *type = parse_typename();
6528
6529         rem_anchor_token(')');
6530         expect(')', end_error);
6531
6532         if (token.type == '{') {
6533                 return parse_compound_literal(type);
6534         }
6535
6536         expression_t *cast = allocate_expression_zero(EXPR_UNARY_CAST);
6537         cast->base.source_position = source_position;
6538
6539         expression_t *value = parse_sub_expression(PREC_CAST);
6540         cast->base.type   = type;
6541         cast->unary.value = value;
6542
6543         if (! semantic_cast(cast)) {
6544                 /* TODO: record the error in the AST. else it is impossible to detect it */
6545         }
6546
6547         return cast;
6548 end_error:
6549         return create_invalid_expression();
6550 }
6551
6552 /**
6553  * Parse a statement expression.
6554  */
6555 static expression_t *parse_statement_expression(void)
6556 {
6557         add_anchor_token(')');
6558
6559         expression_t *expression = allocate_expression_zero(EXPR_STATEMENT);
6560
6561         statement_t *statement          = parse_compound_statement(true);
6562         statement->compound.stmt_expr   = true;
6563         expression->statement.statement = statement;
6564
6565         /* find last statement and use its type */
6566         type_t *type = type_void;
6567         const statement_t *stmt = statement->compound.statements;
6568         if (stmt != NULL) {
6569                 while (stmt->base.next != NULL)
6570                         stmt = stmt->base.next;
6571
6572                 if (stmt->kind == STATEMENT_EXPRESSION) {
6573                         type = stmt->expression.expression->base.type;
6574                 }
6575         } else if (warning.other) {
6576                 warningf(&expression->base.source_position, "empty statement expression ({})");
6577         }
6578         expression->base.type = type;
6579
6580         rem_anchor_token(')');
6581         expect(')', end_error);
6582
6583 end_error:
6584         return expression;
6585 }
6586
6587 /**
6588  * Parse a parenthesized expression.
6589  */
6590 static expression_t *parse_parenthesized_expression(void)
6591 {
6592         eat('(');
6593
6594         switch (token.type) {
6595         case '{':
6596                 /* gcc extension: a statement expression */
6597                 return parse_statement_expression();
6598
6599         TYPE_QUALIFIERS
6600         TYPE_SPECIFIERS
6601                 return parse_cast();
6602         case T_IDENTIFIER:
6603                 if (is_typedef_symbol(token.symbol)) {
6604                         return parse_cast();
6605                 }
6606         }
6607
6608         add_anchor_token(')');
6609         expression_t *result = parse_expression();
6610         result->base.parenthesized = true;
6611         rem_anchor_token(')');
6612         expect(')', end_error);
6613
6614 end_error:
6615         return result;
6616 }
6617
6618 static expression_t *parse_function_keyword(void)
6619 {
6620         /* TODO */
6621
6622         if (current_function == NULL) {
6623                 errorf(HERE, "'__func__' used outside of a function");
6624         }
6625
6626         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6627         expression->base.type     = type_char_ptr;
6628         expression->funcname.kind = FUNCNAME_FUNCTION;
6629
6630         next_token();
6631
6632         return expression;
6633 }
6634
6635 static expression_t *parse_pretty_function_keyword(void)
6636 {
6637         if (current_function == NULL) {
6638                 errorf(HERE, "'__PRETTY_FUNCTION__' used outside of a function");
6639         }
6640
6641         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6642         expression->base.type     = type_char_ptr;
6643         expression->funcname.kind = FUNCNAME_PRETTY_FUNCTION;
6644
6645         eat(T___PRETTY_FUNCTION__);
6646
6647         return expression;
6648 }
6649
6650 static expression_t *parse_funcsig_keyword(void)
6651 {
6652         if (current_function == NULL) {
6653                 errorf(HERE, "'__FUNCSIG__' used outside of a function");
6654         }
6655
6656         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6657         expression->base.type     = type_char_ptr;
6658         expression->funcname.kind = FUNCNAME_FUNCSIG;
6659
6660         eat(T___FUNCSIG__);
6661
6662         return expression;
6663 }
6664
6665 static expression_t *parse_funcdname_keyword(void)
6666 {
6667         if (current_function == NULL) {
6668                 errorf(HERE, "'__FUNCDNAME__' used outside of a function");
6669         }
6670
6671         expression_t *expression  = allocate_expression_zero(EXPR_FUNCNAME);
6672         expression->base.type     = type_char_ptr;
6673         expression->funcname.kind = FUNCNAME_FUNCDNAME;
6674
6675         eat(T___FUNCDNAME__);
6676
6677         return expression;
6678 }
6679
6680 static designator_t *parse_designator(void)
6681 {
6682         designator_t *result    = allocate_ast_zero(sizeof(result[0]));
6683         result->source_position = *HERE;
6684
6685         if (token.type != T_IDENTIFIER) {
6686                 parse_error_expected("while parsing member designator",
6687                                      T_IDENTIFIER, NULL);
6688                 return NULL;
6689         }
6690         result->symbol = token.symbol;
6691         next_token();
6692
6693         designator_t *last_designator = result;
6694         while (true) {
6695                 if (next_if('.')) {
6696                         if (token.type != T_IDENTIFIER) {
6697                                 parse_error_expected("while parsing member designator",
6698                                                      T_IDENTIFIER, NULL);
6699                                 return NULL;
6700                         }
6701                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6702                         designator->source_position = *HERE;
6703                         designator->symbol          = token.symbol;
6704                         next_token();
6705
6706                         last_designator->next = designator;
6707                         last_designator       = designator;
6708                         continue;
6709                 }
6710                 if (next_if('[')) {
6711                         add_anchor_token(']');
6712                         designator_t *designator    = allocate_ast_zero(sizeof(result[0]));
6713                         designator->source_position = *HERE;
6714                         designator->array_index     = parse_expression();
6715                         rem_anchor_token(']');
6716                         expect(']', end_error);
6717                         if (designator->array_index == NULL) {
6718                                 return NULL;
6719                         }
6720
6721                         last_designator->next = designator;
6722                         last_designator       = designator;
6723                         continue;
6724                 }
6725                 break;
6726         }
6727
6728         return result;
6729 end_error:
6730         return NULL;
6731 }
6732
6733 /**
6734  * Parse the __builtin_offsetof() expression.
6735  */
6736 static expression_t *parse_offsetof(void)
6737 {
6738         expression_t *expression = allocate_expression_zero(EXPR_OFFSETOF);
6739         expression->base.type    = type_size_t;
6740
6741         eat(T___builtin_offsetof);
6742
6743         expect('(', end_error);
6744         add_anchor_token(',');
6745         type_t *type = parse_typename();
6746         rem_anchor_token(',');
6747         expect(',', end_error);
6748         add_anchor_token(')');
6749         designator_t *designator = parse_designator();
6750         rem_anchor_token(')');
6751         expect(')', end_error);
6752
6753         expression->offsetofe.type       = type;
6754         expression->offsetofe.designator = designator;
6755
6756         type_path_t path;
6757         memset(&path, 0, sizeof(path));
6758         path.top_type = type;
6759         path.path     = NEW_ARR_F(type_path_entry_t, 0);
6760
6761         descend_into_subtype(&path);
6762
6763         if (!walk_designator(&path, designator, true)) {
6764                 return create_invalid_expression();
6765         }
6766
6767         DEL_ARR_F(path.path);
6768
6769         return expression;
6770 end_error:
6771         return create_invalid_expression();
6772 }
6773
6774 /**
6775  * Parses a _builtin_va_start() expression.
6776  */
6777 static expression_t *parse_va_start(void)
6778 {
6779         expression_t *expression = allocate_expression_zero(EXPR_VA_START);
6780
6781         eat(T___builtin_va_start);
6782
6783         expect('(', end_error);
6784         add_anchor_token(',');
6785         expression->va_starte.ap = parse_assignment_expression();
6786         rem_anchor_token(',');
6787         expect(',', end_error);
6788         expression_t *const expr = parse_assignment_expression();
6789         if (expr->kind == EXPR_REFERENCE) {
6790                 entity_t *const entity = expr->reference.entity;
6791                 if (!current_function->base.type->function.variadic) {
6792                         errorf(&expr->base.source_position,
6793                                         "'va_start' used in non-variadic function");
6794                 } else if (entity->base.parent_scope != &current_function->parameters ||
6795                                 entity->base.next != NULL ||
6796                                 entity->kind != ENTITY_PARAMETER) {
6797                         errorf(&expr->base.source_position,
6798                                "second argument of 'va_start' must be last parameter of the current function");
6799                 } else {
6800                         expression->va_starte.parameter = &entity->variable;
6801                 }
6802                 expect(')', end_error);
6803                 return expression;
6804         }
6805         expect(')', end_error);
6806 end_error:
6807         return create_invalid_expression();
6808 }
6809
6810 /**
6811  * Parses a __builtin_va_arg() expression.
6812  */
6813 static expression_t *parse_va_arg(void)
6814 {
6815         expression_t *expression = allocate_expression_zero(EXPR_VA_ARG);
6816
6817         eat(T___builtin_va_arg);
6818
6819         expect('(', end_error);
6820         call_argument_t ap;
6821         ap.expression = parse_assignment_expression();
6822         expression->va_arge.ap = ap.expression;
6823         check_call_argument(type_valist, &ap, 1);
6824
6825         expect(',', end_error);
6826         expression->base.type = parse_typename();
6827         expect(')', end_error);
6828
6829         return expression;
6830 end_error:
6831         return create_invalid_expression();
6832 }
6833
6834 /**
6835  * Parses a __builtin_va_copy() expression.
6836  */
6837 static expression_t *parse_va_copy(void)
6838 {
6839         expression_t *expression = allocate_expression_zero(EXPR_VA_COPY);
6840
6841         eat(T___builtin_va_copy);
6842
6843         expect('(', end_error);
6844         expression_t *dst = parse_assignment_expression();
6845         assign_error_t error = semantic_assign(type_valist, dst);
6846         report_assign_error(error, type_valist, dst, "call argument 1",
6847                             &dst->base.source_position);
6848         expression->va_copye.dst = dst;
6849
6850         expect(',', end_error);
6851
6852         call_argument_t src;
6853         src.expression = parse_assignment_expression();
6854         check_call_argument(type_valist, &src, 2);
6855         expression->va_copye.src = src.expression;
6856         expect(')', end_error);
6857
6858         return expression;
6859 end_error:
6860         return create_invalid_expression();
6861 }
6862
6863 /**
6864  * Parses a __builtin_constant_p() expression.
6865  */
6866 static expression_t *parse_builtin_constant(void)
6867 {
6868         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_CONSTANT_P);
6869
6870         eat(T___builtin_constant_p);
6871
6872         expect('(', end_error);
6873         add_anchor_token(')');
6874         expression->builtin_constant.value = parse_assignment_expression();
6875         rem_anchor_token(')');
6876         expect(')', end_error);
6877         expression->base.type = type_int;
6878
6879         return expression;
6880 end_error:
6881         return create_invalid_expression();
6882 }
6883
6884 /**
6885  * Parses a __builtin_types_compatible_p() expression.
6886  */
6887 static expression_t *parse_builtin_types_compatible(void)
6888 {
6889         expression_t *expression = allocate_expression_zero(EXPR_BUILTIN_TYPES_COMPATIBLE_P);
6890
6891         eat(T___builtin_types_compatible_p);
6892
6893         expect('(', end_error);
6894         add_anchor_token(')');
6895         add_anchor_token(',');
6896         expression->builtin_types_compatible.left = parse_typename();
6897         rem_anchor_token(',');
6898         expect(',', end_error);
6899         expression->builtin_types_compatible.right = parse_typename();
6900         rem_anchor_token(')');
6901         expect(')', end_error);
6902         expression->base.type = type_int;
6903
6904         return expression;
6905 end_error:
6906         return create_invalid_expression();
6907 }
6908
6909 /**
6910  * Parses a __builtin_is_*() compare expression.
6911  */
6912 static expression_t *parse_compare_builtin(void)
6913 {
6914         expression_t *expression;
6915
6916         switch (token.type) {
6917         case T___builtin_isgreater:
6918                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATER);
6919                 break;
6920         case T___builtin_isgreaterequal:
6921                 expression = allocate_expression_zero(EXPR_BINARY_ISGREATEREQUAL);
6922                 break;
6923         case T___builtin_isless:
6924                 expression = allocate_expression_zero(EXPR_BINARY_ISLESS);
6925                 break;
6926         case T___builtin_islessequal:
6927                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSEQUAL);
6928                 break;
6929         case T___builtin_islessgreater:
6930                 expression = allocate_expression_zero(EXPR_BINARY_ISLESSGREATER);
6931                 break;
6932         case T___builtin_isunordered:
6933                 expression = allocate_expression_zero(EXPR_BINARY_ISUNORDERED);
6934                 break;
6935         default:
6936                 internal_errorf(HERE, "invalid compare builtin found");
6937         }
6938         expression->base.source_position = *HERE;
6939         next_token();
6940
6941         expect('(', end_error);
6942         expression->binary.left = parse_assignment_expression();
6943         expect(',', end_error);
6944         expression->binary.right = parse_assignment_expression();
6945         expect(')', end_error);
6946
6947         type_t *const orig_type_left  = expression->binary.left->base.type;
6948         type_t *const orig_type_right = expression->binary.right->base.type;
6949
6950         type_t *const type_left  = skip_typeref(orig_type_left);
6951         type_t *const type_right = skip_typeref(orig_type_right);
6952         if (!is_type_float(type_left) && !is_type_float(type_right)) {
6953                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
6954                         type_error_incompatible("invalid operands in comparison",
6955                                 &expression->base.source_position, orig_type_left, orig_type_right);
6956                 }
6957         } else {
6958                 semantic_comparison(&expression->binary);
6959         }
6960
6961         return expression;
6962 end_error:
6963         return create_invalid_expression();
6964 }
6965
6966 /**
6967  * Parses a MS assume() expression.
6968  */
6969 static expression_t *parse_assume(void)
6970 {
6971         expression_t *expression = allocate_expression_zero(EXPR_UNARY_ASSUME);
6972
6973         eat(T__assume);
6974
6975         expect('(', end_error);
6976         add_anchor_token(')');
6977         expression->unary.value = parse_assignment_expression();
6978         rem_anchor_token(')');
6979         expect(')', end_error);
6980
6981         expression->base.type = type_void;
6982         return expression;
6983 end_error:
6984         return create_invalid_expression();
6985 }
6986
6987 /**
6988  * Return the declaration for a given label symbol or create a new one.
6989  *
6990  * @param symbol  the symbol of the label
6991  */
6992 static label_t *get_label(symbol_t *symbol)
6993 {
6994         entity_t *label;
6995         assert(current_function != NULL);
6996
6997         label = get_entity(symbol, NAMESPACE_LABEL);
6998         /* if we found a local label, we already created the declaration */
6999         if (label != NULL && label->kind == ENTITY_LOCAL_LABEL) {
7000                 if (label->base.parent_scope != current_scope) {
7001                         assert(label->base.parent_scope->depth < current_scope->depth);
7002                         current_function->goto_to_outer = true;
7003                 }
7004                 return &label->label;
7005         }
7006
7007         label = get_entity(symbol, NAMESPACE_LABEL);
7008         /* if we found a label in the same function, then we already created the
7009          * declaration */
7010         if (label != NULL
7011                         && label->base.parent_scope == &current_function->parameters) {
7012                 return &label->label;
7013         }
7014
7015         /* otherwise we need to create a new one */
7016         label               = allocate_entity_zero(ENTITY_LABEL);
7017         label->base.namespc = NAMESPACE_LABEL;
7018         label->base.symbol  = symbol;
7019
7020         label_push(label);
7021
7022         return &label->label;
7023 }
7024
7025 /**
7026  * Parses a GNU && label address expression.
7027  */
7028 static expression_t *parse_label_address(void)
7029 {
7030         source_position_t source_position = token.source_position;
7031         eat(T_ANDAND);
7032         if (token.type != T_IDENTIFIER) {
7033                 parse_error_expected("while parsing label address", T_IDENTIFIER, NULL);
7034                 goto end_error;
7035         }
7036         symbol_t *symbol = token.symbol;
7037         next_token();
7038
7039         label_t *label       = get_label(symbol);
7040         label->used          = true;
7041         label->address_taken = true;
7042
7043         expression_t *expression = allocate_expression_zero(EXPR_LABEL_ADDRESS);
7044         expression->base.source_position = source_position;
7045
7046         /* label address is threaten as a void pointer */
7047         expression->base.type           = type_void_ptr;
7048         expression->label_address.label = label;
7049         return expression;
7050 end_error:
7051         return create_invalid_expression();
7052 }
7053
7054 /**
7055  * Parse a microsoft __noop expression.
7056  */
7057 static expression_t *parse_noop_expression(void)
7058 {
7059         /* the result is a (int)0 */
7060         expression_t *literal = allocate_expression_zero(EXPR_LITERAL_MS_NOOP);
7061         literal->base.type            = type_int;
7062         literal->base.source_position = token.source_position;
7063         literal->literal.value.begin  = "__noop";
7064         literal->literal.value.size   = 6;
7065
7066         eat(T___noop);
7067
7068         if (token.type == '(') {
7069                 /* parse arguments */
7070                 eat('(');
7071                 add_anchor_token(')');
7072                 add_anchor_token(',');
7073
7074                 if (token.type != ')') do {
7075                         (void)parse_assignment_expression();
7076                 } while (next_if(','));
7077         }
7078         rem_anchor_token(',');
7079         rem_anchor_token(')');
7080         expect(')', end_error);
7081
7082 end_error:
7083         return literal;
7084 }
7085
7086 /**
7087  * Parses a primary expression.
7088  */
7089 static expression_t *parse_primary_expression(void)
7090 {
7091         switch (token.type) {
7092         case T_false:                        return parse_boolean_literal(false);
7093         case T_true:                         return parse_boolean_literal(true);
7094         case T_INTEGER:
7095         case T_INTEGER_OCTAL:
7096         case T_INTEGER_HEXADECIMAL:
7097         case T_FLOATINGPOINT:
7098         case T_FLOATINGPOINT_HEXADECIMAL:    return parse_number_literal();
7099         case T_CHARACTER_CONSTANT:           return parse_character_constant();
7100         case T_WIDE_CHARACTER_CONSTANT:      return parse_wide_character_constant();
7101         case T_STRING_LITERAL:
7102         case T_WIDE_STRING_LITERAL:          return parse_string_literal();
7103         case T___FUNCTION__:
7104         case T___func__:                     return parse_function_keyword();
7105         case T___PRETTY_FUNCTION__:          return parse_pretty_function_keyword();
7106         case T___FUNCSIG__:                  return parse_funcsig_keyword();
7107         case T___FUNCDNAME__:                return parse_funcdname_keyword();
7108         case T___builtin_offsetof:           return parse_offsetof();
7109         case T___builtin_va_start:           return parse_va_start();
7110         case T___builtin_va_arg:             return parse_va_arg();
7111         case T___builtin_va_copy:            return parse_va_copy();
7112         case T___builtin_isgreater:
7113         case T___builtin_isgreaterequal:
7114         case T___builtin_isless:
7115         case T___builtin_islessequal:
7116         case T___builtin_islessgreater:
7117         case T___builtin_isunordered:        return parse_compare_builtin();
7118         case T___builtin_constant_p:         return parse_builtin_constant();
7119         case T___builtin_types_compatible_p: return parse_builtin_types_compatible();
7120         case T__assume:                      return parse_assume();
7121         case T_ANDAND:
7122                 if (GNU_MODE)
7123                         return parse_label_address();
7124                 break;
7125
7126         case '(':                            return parse_parenthesized_expression();
7127         case T___noop:                       return parse_noop_expression();
7128
7129         /* Gracefully handle type names while parsing expressions. */
7130         case T_COLONCOLON:
7131                 return parse_reference();
7132         case T_IDENTIFIER:
7133                 if (!is_typedef_symbol(token.symbol)) {
7134                         return parse_reference();
7135                 }
7136                 /* FALLTHROUGH */
7137         TYPENAME_START {
7138                 source_position_t  const pos  = *HERE;
7139                 type_t const      *const type = parse_typename();
7140                 errorf(&pos, "encountered type '%T' while parsing expression", type);
7141                 return create_invalid_expression();
7142         }
7143         }
7144
7145         errorf(HERE, "unexpected token %K, expected an expression", &token);
7146         return create_invalid_expression();
7147 }
7148
7149 /**
7150  * Check if the expression has the character type and issue a warning then.
7151  */
7152 static void check_for_char_index_type(const expression_t *expression)
7153 {
7154         type_t       *const type      = expression->base.type;
7155         const type_t *const base_type = skip_typeref(type);
7156
7157         if (is_type_atomic(base_type, ATOMIC_TYPE_CHAR) &&
7158                         warning.char_subscripts) {
7159                 warningf(&expression->base.source_position,
7160                          "array subscript has type '%T'", type);
7161         }
7162 }
7163
7164 static expression_t *parse_array_expression(expression_t *left)
7165 {
7166         expression_t *expression = allocate_expression_zero(EXPR_ARRAY_ACCESS);
7167
7168         eat('[');
7169         add_anchor_token(']');
7170
7171         expression_t *inside = parse_expression();
7172
7173         type_t *const orig_type_left   = left->base.type;
7174         type_t *const orig_type_inside = inside->base.type;
7175
7176         type_t *const type_left   = skip_typeref(orig_type_left);
7177         type_t *const type_inside = skip_typeref(orig_type_inside);
7178
7179         type_t                    *return_type;
7180         array_access_expression_t *array_access = &expression->array_access;
7181         if (is_type_pointer(type_left)) {
7182                 return_type             = type_left->pointer.points_to;
7183                 array_access->array_ref = left;
7184                 array_access->index     = inside;
7185                 check_for_char_index_type(inside);
7186         } else if (is_type_pointer(type_inside)) {
7187                 return_type             = type_inside->pointer.points_to;
7188                 array_access->array_ref = inside;
7189                 array_access->index     = left;
7190                 array_access->flipped   = true;
7191                 check_for_char_index_type(left);
7192         } else {
7193                 if (is_type_valid(type_left) && is_type_valid(type_inside)) {
7194                         errorf(HERE,
7195                                 "array access on object with non-pointer types '%T', '%T'",
7196                                 orig_type_left, orig_type_inside);
7197                 }
7198                 return_type             = type_error_type;
7199                 array_access->array_ref = left;
7200                 array_access->index     = inside;
7201         }
7202
7203         expression->base.type = automatic_type_conversion(return_type);
7204
7205         rem_anchor_token(']');
7206         expect(']', end_error);
7207 end_error:
7208         return expression;
7209 }
7210
7211 static expression_t *parse_typeprop(expression_kind_t const kind)
7212 {
7213         expression_t  *tp_expression = allocate_expression_zero(kind);
7214         tp_expression->base.type     = type_size_t;
7215
7216         eat(kind == EXPR_SIZEOF ? T_sizeof : T___alignof__);
7217
7218         /* we only refer to a type property, mark this case */
7219         bool old     = in_type_prop;
7220         in_type_prop = true;
7221
7222         type_t       *orig_type;
7223         expression_t *expression;
7224         if (token.type == '(' && is_declaration_specifier(look_ahead(1), true)) {
7225                 next_token();
7226                 add_anchor_token(')');
7227                 orig_type = parse_typename();
7228                 rem_anchor_token(')');
7229                 expect(')', end_error);
7230
7231                 if (token.type == '{') {
7232                         /* It was not sizeof(type) after all.  It is sizeof of an expression
7233                          * starting with a compound literal */
7234                         expression = parse_compound_literal(orig_type);
7235                         goto typeprop_expression;
7236                 }
7237         } else {
7238                 expression = parse_sub_expression(PREC_UNARY);
7239
7240 typeprop_expression:
7241                 tp_expression->typeprop.tp_expression = expression;
7242
7243                 orig_type = revert_automatic_type_conversion(expression);
7244                 expression->base.type = orig_type;
7245         }
7246
7247         tp_expression->typeprop.type   = orig_type;
7248         type_t const* const type       = skip_typeref(orig_type);
7249         char   const* const wrong_type =
7250                 GNU_MODE && is_type_atomic(type, ATOMIC_TYPE_VOID) ? NULL                  :
7251                 is_type_incomplete(type)                           ? "incomplete"          :
7252                 type->kind == TYPE_FUNCTION                        ? "function designator" :
7253                 type->kind == TYPE_BITFIELD                        ? "bitfield"            :
7254                 NULL;
7255         if (wrong_type != NULL) {
7256                 char const* const what = kind == EXPR_SIZEOF ? "sizeof" : "alignof";
7257                 errorf(&tp_expression->base.source_position,
7258                                 "operand of %s expression must not be of %s type '%T'",
7259                                 what, wrong_type, orig_type);
7260         }
7261
7262 end_error:
7263         in_type_prop = old;
7264         return tp_expression;
7265 }
7266
7267 static expression_t *parse_sizeof(void)
7268 {
7269         return parse_typeprop(EXPR_SIZEOF);
7270 }
7271
7272 static expression_t *parse_alignof(void)
7273 {
7274         return parse_typeprop(EXPR_ALIGNOF);
7275 }
7276
7277 static expression_t *parse_select_expression(expression_t *addr)
7278 {
7279         assert(token.type == '.' || token.type == T_MINUSGREATER);
7280         bool select_left_arrow = (token.type == T_MINUSGREATER);
7281         next_token();
7282
7283         if (token.type != T_IDENTIFIER) {
7284                 parse_error_expected("while parsing select", T_IDENTIFIER, NULL);
7285                 return create_invalid_expression();
7286         }
7287         symbol_t *symbol = token.symbol;
7288         next_token();
7289
7290         type_t *const orig_type = addr->base.type;
7291         type_t *const type      = skip_typeref(orig_type);
7292
7293         type_t *type_left;
7294         bool    saw_error = false;
7295         if (is_type_pointer(type)) {
7296                 if (!select_left_arrow) {
7297                         errorf(HERE,
7298                                "request for member '%Y' in something not a struct or union, but '%T'",
7299                                symbol, orig_type);
7300                         saw_error = true;
7301                 }
7302                 type_left = skip_typeref(type->pointer.points_to);
7303         } else {
7304                 if (select_left_arrow && is_type_valid(type)) {
7305                         errorf(HERE, "left hand side of '->' is not a pointer, but '%T'", orig_type);
7306                         saw_error = true;
7307                 }
7308                 type_left = type;
7309         }
7310
7311         if (type_left->kind != TYPE_COMPOUND_STRUCT &&
7312             type_left->kind != TYPE_COMPOUND_UNION) {
7313
7314                 if (is_type_valid(type_left) && !saw_error) {
7315                         errorf(HERE,
7316                                "request for member '%Y' in something not a struct or union, but '%T'",
7317                                symbol, type_left);
7318                 }
7319                 return create_invalid_expression();
7320         }
7321
7322         compound_t *compound = type_left->compound.compound;
7323         if (!compound->complete) {
7324                 errorf(HERE, "request for member '%Y' in incomplete type '%T'",
7325                        symbol, type_left);
7326                 return create_invalid_expression();
7327         }
7328
7329         type_qualifiers_t  qualifiers = type_left->base.qualifiers;
7330         expression_t      *result
7331                 = find_create_select(HERE, addr, qualifiers, compound, symbol);
7332
7333         if (result == NULL) {
7334                 errorf(HERE, "'%T' has no member named '%Y'", orig_type, symbol);
7335                 return create_invalid_expression();
7336         }
7337
7338         return result;
7339 }
7340
7341 static void check_call_argument(type_t          *expected_type,
7342                                 call_argument_t *argument, unsigned pos)
7343 {
7344         type_t         *expected_type_skip = skip_typeref(expected_type);
7345         assign_error_t  error              = ASSIGN_ERROR_INCOMPATIBLE;
7346         expression_t   *arg_expr           = argument->expression;
7347         type_t         *arg_type           = skip_typeref(arg_expr->base.type);
7348
7349         /* handle transparent union gnu extension */
7350         if (is_type_union(expected_type_skip)
7351                         && (get_type_modifiers(expected_type) & DM_TRANSPARENT_UNION)) {
7352                 compound_t *union_decl  = expected_type_skip->compound.compound;
7353                 type_t     *best_type   = NULL;
7354                 entity_t   *entry       = union_decl->members.entities;
7355                 for ( ; entry != NULL; entry = entry->base.next) {
7356                         assert(is_declaration(entry));
7357                         type_t *decl_type = entry->declaration.type;
7358                         error = semantic_assign(decl_type, arg_expr);
7359                         if (error == ASSIGN_ERROR_INCOMPATIBLE
7360                                 || error == ASSIGN_ERROR_POINTER_QUALIFIER_MISSING)
7361                                 continue;
7362
7363                         if (error == ASSIGN_SUCCESS) {
7364                                 best_type = decl_type;
7365                         } else if (best_type == NULL) {
7366                                 best_type = decl_type;
7367                         }
7368                 }
7369
7370                 if (best_type != NULL) {
7371                         expected_type = best_type;
7372                 }
7373         }
7374
7375         error                = semantic_assign(expected_type, arg_expr);
7376         argument->expression = create_implicit_cast(arg_expr, expected_type);
7377
7378         if (error != ASSIGN_SUCCESS) {
7379                 /* report exact scope in error messages (like "in argument 3") */
7380                 char buf[64];
7381                 snprintf(buf, sizeof(buf), "call argument %u", pos);
7382                 report_assign_error(error, expected_type, arg_expr,     buf,
7383                                                         &arg_expr->base.source_position);
7384         } else if (warning.traditional || warning.conversion) {
7385                 type_t *const promoted_type = get_default_promoted_type(arg_type);
7386                 if (!types_compatible(expected_type_skip, promoted_type) &&
7387                     !types_compatible(expected_type_skip, type_void_ptr) &&
7388                     !types_compatible(type_void_ptr,      promoted_type)) {
7389                         /* Deliberately show the skipped types in this warning */
7390                         warningf(&arg_expr->base.source_position,
7391                                 "passing call argument %u as '%T' rather than '%T' due to prototype",
7392                                 pos, expected_type_skip, promoted_type);
7393                 }
7394         }
7395 }
7396
7397 /**
7398  * Handle the semantic restrictions of builtin calls
7399  */
7400 static void handle_builtin_argument_restrictions(call_expression_t *call) {
7401         switch (call->function->reference.entity->function.btk) {
7402                 case bk_gnu_builtin_return_address:
7403                 case bk_gnu_builtin_frame_address: {
7404                         /* argument must be constant */
7405                         call_argument_t *argument = call->arguments;
7406
7407                         if (! is_constant_expression(argument->expression)) {
7408                                 errorf(&call->base.source_position,
7409                                        "argument of '%Y' must be a constant expression",
7410                                        call->function->reference.entity->base.symbol);
7411                         }
7412                         break;
7413                 }
7414                 case bk_gnu_builtin_prefetch: {
7415                         /* second and third argument must be constant if existent */
7416                         call_argument_t *rw = call->arguments->next;
7417                         call_argument_t *locality = NULL;
7418
7419                         if (rw != NULL) {
7420                                 if (! is_constant_expression(rw->expression)) {
7421                                         errorf(&call->base.source_position,
7422                                                "second argument of '%Y' must be a constant expression",
7423                                                call->function->reference.entity->base.symbol);
7424                                 }
7425                                 locality = rw->next;
7426                         }
7427                         if (locality != NULL) {
7428                                 if (! is_constant_expression(locality->expression)) {
7429                                         errorf(&call->base.source_position,
7430                                                "third argument of '%Y' must be a constant expression",
7431                                                call->function->reference.entity->base.symbol);
7432                                 }
7433                                 locality = rw->next;
7434                         }
7435                         break;
7436                 }
7437                 default:
7438                         break;
7439         }
7440 }
7441
7442 /**
7443  * Parse a call expression, ie. expression '( ... )'.
7444  *
7445  * @param expression  the function address
7446  */
7447 static expression_t *parse_call_expression(expression_t *expression)
7448 {
7449         expression_t      *result = allocate_expression_zero(EXPR_CALL);
7450         call_expression_t *call   = &result->call;
7451         call->function            = expression;
7452
7453         type_t *const orig_type = expression->base.type;
7454         type_t *const type      = skip_typeref(orig_type);
7455
7456         function_type_t *function_type = NULL;
7457         if (is_type_pointer(type)) {
7458                 type_t *const to_type = skip_typeref(type->pointer.points_to);
7459
7460                 if (is_type_function(to_type)) {
7461                         function_type   = &to_type->function;
7462                         call->base.type = function_type->return_type;
7463                 }
7464         }
7465
7466         if (function_type == NULL && is_type_valid(type)) {
7467                 errorf(HERE,
7468                        "called object '%E' (type '%T') is not a pointer to a function",
7469                        expression, orig_type);
7470         }
7471
7472         /* parse arguments */
7473         eat('(');
7474         add_anchor_token(')');
7475         add_anchor_token(',');
7476
7477         if (token.type != ')') {
7478                 call_argument_t **anchor = &call->arguments;
7479                 do {
7480                         call_argument_t *argument = allocate_ast_zero(sizeof(*argument));
7481                         argument->expression = parse_assignment_expression();
7482
7483                         *anchor = argument;
7484                         anchor  = &argument->next;
7485                 } while (next_if(','));
7486         }
7487         rem_anchor_token(',');
7488         rem_anchor_token(')');
7489         expect(')', end_error);
7490
7491         if (function_type == NULL)
7492                 return result;
7493
7494         /* check type and count of call arguments */
7495         function_parameter_t *parameter = function_type->parameters;
7496         call_argument_t      *argument  = call->arguments;
7497         if (!function_type->unspecified_parameters) {
7498                 for (unsigned pos = 0; parameter != NULL && argument != NULL;
7499                                 parameter = parameter->next, argument = argument->next) {
7500                         check_call_argument(parameter->type, argument, ++pos);
7501                 }
7502
7503                 if (parameter != NULL) {
7504                         errorf(HERE, "too few arguments to function '%E'", expression);
7505                 } else if (argument != NULL && !function_type->variadic) {
7506                         errorf(HERE, "too many arguments to function '%E'", expression);
7507                 }
7508         }
7509
7510         /* do default promotion for other arguments */
7511         for (; argument != NULL; argument = argument->next) {
7512                 type_t *type = argument->expression->base.type;
7513
7514                 type = get_default_promoted_type(type);
7515
7516                 argument->expression
7517                         = create_implicit_cast(argument->expression, type);
7518         }
7519
7520         check_format(&result->call);
7521
7522         if (warning.aggregate_return &&
7523             is_type_compound(skip_typeref(function_type->return_type))) {
7524                 warningf(&result->base.source_position,
7525                          "function call has aggregate value");
7526         }
7527
7528         if (call->function->kind == EXPR_REFERENCE) {
7529                 reference_expression_t *reference = &call->function->reference;
7530                 if (reference->entity->kind == ENTITY_FUNCTION &&
7531                     reference->entity->function.btk != bk_none)
7532                         handle_builtin_argument_restrictions(call);
7533         }
7534
7535 end_error:
7536         return result;
7537 }
7538
7539 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right);
7540
7541 static bool same_compound_type(const type_t *type1, const type_t *type2)
7542 {
7543         return
7544                 is_type_compound(type1) &&
7545                 type1->kind == type2->kind &&
7546                 type1->compound.compound == type2->compound.compound;
7547 }
7548
7549 static expression_t const *get_reference_address(expression_t const *expr)
7550 {
7551         bool regular_take_address = true;
7552         for (;;) {
7553                 if (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
7554                         expr = expr->unary.value;
7555                 } else {
7556                         regular_take_address = false;
7557                 }
7558
7559                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
7560                         break;
7561
7562                 expr = expr->unary.value;
7563         }
7564
7565         if (expr->kind != EXPR_REFERENCE)
7566                 return NULL;
7567
7568         /* special case for functions which are automatically converted to a
7569          * pointer to function without an extra TAKE_ADDRESS operation */
7570         if (!regular_take_address &&
7571                         expr->reference.entity->kind != ENTITY_FUNCTION) {
7572                 return NULL;
7573         }
7574
7575         return expr;
7576 }
7577
7578 static void warn_reference_address_as_bool(expression_t const* expr)
7579 {
7580         if (!warning.address)
7581                 return;
7582
7583         expr = get_reference_address(expr);
7584         if (expr != NULL) {
7585                 warningf(&expr->base.source_position,
7586                          "the address of '%Y' will always evaluate as 'true'",
7587                          expr->reference.entity->base.symbol);
7588         }
7589 }
7590
7591 static void warn_assignment_in_condition(const expression_t *const expr)
7592 {
7593         if (!warning.parentheses)
7594                 return;
7595         if (expr->base.kind != EXPR_BINARY_ASSIGN)
7596                 return;
7597         if (expr->base.parenthesized)
7598                 return;
7599         warningf(&expr->base.source_position,
7600                         "suggest parentheses around assignment used as truth value");
7601 }
7602
7603 static void semantic_condition(expression_t const *const expr,
7604                                char const *const context)
7605 {
7606         type_t *const type = skip_typeref(expr->base.type);
7607         if (is_type_scalar(type)) {
7608                 warn_reference_address_as_bool(expr);
7609                 warn_assignment_in_condition(expr);
7610         } else if (is_type_valid(type)) {
7611                 errorf(&expr->base.source_position,
7612                                 "%s must have scalar type", context);
7613         }
7614 }
7615
7616 /**
7617  * Parse a conditional expression, ie. 'expression ? ... : ...'.
7618  *
7619  * @param expression  the conditional expression
7620  */
7621 static expression_t *parse_conditional_expression(expression_t *expression)
7622 {
7623         expression_t *result = allocate_expression_zero(EXPR_CONDITIONAL);
7624
7625         conditional_expression_t *conditional = &result->conditional;
7626         conditional->condition                = expression;
7627
7628         eat('?');
7629         add_anchor_token(':');
7630
7631         /* §6.5.15:2  The first operand shall have scalar type. */
7632         semantic_condition(expression, "condition of conditional operator");
7633
7634         expression_t *true_expression = expression;
7635         bool          gnu_cond = false;
7636         if (GNU_MODE && token.type == ':') {
7637                 gnu_cond = true;
7638         } else {
7639                 true_expression = parse_expression();
7640         }
7641         rem_anchor_token(':');
7642         expect(':', end_error);
7643 end_error:;
7644         expression_t *false_expression =
7645                 parse_sub_expression(c_mode & _CXX ? PREC_ASSIGNMENT : PREC_CONDITIONAL);
7646
7647         type_t *const orig_true_type  = true_expression->base.type;
7648         type_t *const orig_false_type = false_expression->base.type;
7649         type_t *const true_type       = skip_typeref(orig_true_type);
7650         type_t *const false_type      = skip_typeref(orig_false_type);
7651
7652         /* 6.5.15.3 */
7653         type_t *result_type;
7654         if (is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
7655                         is_type_atomic(false_type, ATOMIC_TYPE_VOID)) {
7656                 /* ISO/IEC 14882:1998(E) §5.16:2 */
7657                 if (true_expression->kind == EXPR_UNARY_THROW) {
7658                         result_type = false_type;
7659                 } else if (false_expression->kind == EXPR_UNARY_THROW) {
7660                         result_type = true_type;
7661                 } else {
7662                         if (warning.other && (
7663                                                 !is_type_atomic(true_type,  ATOMIC_TYPE_VOID) ||
7664                                                 !is_type_atomic(false_type, ATOMIC_TYPE_VOID)
7665                                         )) {
7666                                 warningf(&conditional->base.source_position,
7667                                                 "ISO C forbids conditional expression with only one void side");
7668                         }
7669                         result_type = type_void;
7670                 }
7671         } else if (is_type_arithmetic(true_type)
7672                    && is_type_arithmetic(false_type)) {
7673                 result_type = semantic_arithmetic(true_type, false_type);
7674
7675                 true_expression  = create_implicit_cast(true_expression, result_type);
7676                 false_expression = create_implicit_cast(false_expression, result_type);
7677
7678                 conditional->true_expression  = true_expression;
7679                 conditional->false_expression = false_expression;
7680                 conditional->base.type        = result_type;
7681         } else if (same_compound_type(true_type, false_type)) {
7682                 /* just take 1 of the 2 types */
7683                 result_type = true_type;
7684         } else if (is_type_pointer(true_type) || is_type_pointer(false_type)) {
7685                 type_t *pointer_type;
7686                 type_t *other_type;
7687                 expression_t *other_expression;
7688                 if (is_type_pointer(true_type) &&
7689                                 (!is_type_pointer(false_type) || is_null_pointer_constant(false_expression))) {
7690                         pointer_type     = true_type;
7691                         other_type       = false_type;
7692                         other_expression = false_expression;
7693                 } else {
7694                         pointer_type     = false_type;
7695                         other_type       = true_type;
7696                         other_expression = true_expression;
7697                 }
7698
7699                 if (is_null_pointer_constant(other_expression)) {
7700                         result_type = pointer_type;
7701                 } else if (is_type_pointer(other_type)) {
7702                         type_t *to1 = skip_typeref(pointer_type->pointer.points_to);
7703                         type_t *to2 = skip_typeref(other_type->pointer.points_to);
7704
7705                         type_t *to;
7706                         if (is_type_atomic(to1, ATOMIC_TYPE_VOID) ||
7707                             is_type_atomic(to2, ATOMIC_TYPE_VOID)) {
7708                                 to = type_void;
7709                         } else if (types_compatible(get_unqualified_type(to1),
7710                                                     get_unqualified_type(to2))) {
7711                                 to = to1;
7712                         } else {
7713                                 if (warning.other) {
7714                                         warningf(&conditional->base.source_position,
7715                                                         "pointer types '%T' and '%T' in conditional expression are incompatible",
7716                                                         true_type, false_type);
7717                                 }
7718                                 to = type_void;
7719                         }
7720
7721                         type_t *const type =
7722                                 get_qualified_type(to, to1->base.qualifiers | to2->base.qualifiers);
7723                         result_type = make_pointer_type(type, TYPE_QUALIFIER_NONE);
7724                 } else if (is_type_integer(other_type)) {
7725                         if (warning.other) {
7726                                 warningf(&conditional->base.source_position,
7727                                                 "pointer/integer type mismatch in conditional expression ('%T' and '%T')", true_type, false_type);
7728                         }
7729                         result_type = pointer_type;
7730                 } else {
7731                         if (is_type_valid(other_type)) {
7732                                 type_error_incompatible("while parsing conditional",
7733                                                 &expression->base.source_position, true_type, false_type);
7734                         }
7735                         result_type = type_error_type;
7736                 }
7737         } else {
7738                 if (is_type_valid(true_type) && is_type_valid(false_type)) {
7739                         type_error_incompatible("while parsing conditional",
7740                                                 &conditional->base.source_position, true_type,
7741                                                 false_type);
7742                 }
7743                 result_type = type_error_type;
7744         }
7745
7746         conditional->true_expression
7747                 = gnu_cond ? NULL : create_implicit_cast(true_expression, result_type);
7748         conditional->false_expression
7749                 = create_implicit_cast(false_expression, result_type);
7750         conditional->base.type = result_type;
7751         return result;
7752 }
7753
7754 /**
7755  * Parse an extension expression.
7756  */
7757 static expression_t *parse_extension(void)
7758 {
7759         eat(T___extension__);
7760
7761         bool old_gcc_extension   = in_gcc_extension;
7762         in_gcc_extension         = true;
7763         expression_t *expression = parse_sub_expression(PREC_UNARY);
7764         in_gcc_extension         = old_gcc_extension;
7765         return expression;
7766 }
7767
7768 /**
7769  * Parse a __builtin_classify_type() expression.
7770  */
7771 static expression_t *parse_builtin_classify_type(void)
7772 {
7773         expression_t *result = allocate_expression_zero(EXPR_CLASSIFY_TYPE);
7774         result->base.type    = type_int;
7775
7776         eat(T___builtin_classify_type);
7777
7778         expect('(', end_error);
7779         add_anchor_token(')');
7780         expression_t *expression = parse_expression();
7781         rem_anchor_token(')');
7782         expect(')', end_error);
7783         result->classify_type.type_expression = expression;
7784
7785         return result;
7786 end_error:
7787         return create_invalid_expression();
7788 }
7789
7790 /**
7791  * Parse a delete expression
7792  * ISO/IEC 14882:1998(E) §5.3.5
7793  */
7794 static expression_t *parse_delete(void)
7795 {
7796         expression_t *const result = allocate_expression_zero(EXPR_UNARY_DELETE);
7797         result->base.type          = type_void;
7798
7799         eat(T_delete);
7800
7801         if (next_if('[')) {
7802                 result->kind = EXPR_UNARY_DELETE_ARRAY;
7803                 expect(']', end_error);
7804 end_error:;
7805         }
7806
7807         expression_t *const value = parse_sub_expression(PREC_CAST);
7808         result->unary.value = value;
7809
7810         type_t *const type = skip_typeref(value->base.type);
7811         if (!is_type_pointer(type)) {
7812                 if (is_type_valid(type)) {
7813                         errorf(&value->base.source_position,
7814                                         "operand of delete must have pointer type");
7815                 }
7816         } else if (warning.other &&
7817                         is_type_atomic(skip_typeref(type->pointer.points_to), ATOMIC_TYPE_VOID)) {
7818                 warningf(&value->base.source_position,
7819                                 "deleting 'void*' is undefined");
7820         }
7821
7822         return result;
7823 }
7824
7825 /**
7826  * Parse a throw expression
7827  * ISO/IEC 14882:1998(E) §15:1
7828  */
7829 static expression_t *parse_throw(void)
7830 {
7831         expression_t *const result = allocate_expression_zero(EXPR_UNARY_THROW);
7832         result->base.type          = type_void;
7833
7834         eat(T_throw);
7835
7836         expression_t *value = NULL;
7837         switch (token.type) {
7838                 EXPRESSION_START {
7839                         value = parse_assignment_expression();
7840                         /* ISO/IEC 14882:1998(E) §15.1:3 */
7841                         type_t *const orig_type = value->base.type;
7842                         type_t *const type      = skip_typeref(orig_type);
7843                         if (is_type_incomplete(type)) {
7844                                 errorf(&value->base.source_position,
7845                                                 "cannot throw object of incomplete type '%T'", orig_type);
7846                         } else if (is_type_pointer(type)) {
7847                                 type_t *const points_to = skip_typeref(type->pointer.points_to);
7848                                 if (is_type_incomplete(points_to) &&
7849                                                 !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7850                                         errorf(&value->base.source_position,
7851                                                         "cannot throw pointer to incomplete type '%T'", orig_type);
7852                                 }
7853                         }
7854                 }
7855
7856                 default:
7857                         break;
7858         }
7859         result->unary.value = value;
7860
7861         return result;
7862 }
7863
7864 static bool check_pointer_arithmetic(const source_position_t *source_position,
7865                                      type_t *pointer_type,
7866                                      type_t *orig_pointer_type)
7867 {
7868         type_t *points_to = pointer_type->pointer.points_to;
7869         points_to = skip_typeref(points_to);
7870
7871         if (is_type_incomplete(points_to)) {
7872                 if (!GNU_MODE || !is_type_atomic(points_to, ATOMIC_TYPE_VOID)) {
7873                         errorf(source_position,
7874                                "arithmetic with pointer to incomplete type '%T' not allowed",
7875                                orig_pointer_type);
7876                         return false;
7877                 } else if (warning.pointer_arith) {
7878                         warningf(source_position,
7879                                  "pointer of type '%T' used in arithmetic",
7880                                  orig_pointer_type);
7881                 }
7882         } else if (is_type_function(points_to)) {
7883                 if (!GNU_MODE) {
7884                         errorf(source_position,
7885                                "arithmetic with pointer to function type '%T' not allowed",
7886                                orig_pointer_type);
7887                         return false;
7888                 } else if (warning.pointer_arith) {
7889                         warningf(source_position,
7890                                  "pointer to a function '%T' used in arithmetic",
7891                                  orig_pointer_type);
7892                 }
7893         }
7894         return true;
7895 }
7896
7897 static bool is_lvalue(const expression_t *expression)
7898 {
7899         /* TODO: doesn't seem to be consistent with §6.3.2.1:1 */
7900         switch (expression->kind) {
7901         case EXPR_ARRAY_ACCESS:
7902         case EXPR_COMPOUND_LITERAL:
7903         case EXPR_REFERENCE:
7904         case EXPR_SELECT:
7905         case EXPR_UNARY_DEREFERENCE:
7906                 return true;
7907
7908         default: {
7909                 type_t *type = skip_typeref(expression->base.type);
7910                 return
7911                         /* ISO/IEC 14882:1998(E) §3.10:3 */
7912                         is_type_reference(type) ||
7913                         /* Claim it is an lvalue, if the type is invalid.  There was a parse
7914                          * error before, which maybe prevented properly recognizing it as
7915                          * lvalue. */
7916                         !is_type_valid(type);
7917         }
7918         }
7919 }
7920
7921 static void semantic_incdec(unary_expression_t *expression)
7922 {
7923         type_t *const orig_type = expression->value->base.type;
7924         type_t *const type      = skip_typeref(orig_type);
7925         if (is_type_pointer(type)) {
7926                 if (!check_pointer_arithmetic(&expression->base.source_position,
7927                                               type, orig_type)) {
7928                         return;
7929                 }
7930         } else if (!is_type_real(type) && is_type_valid(type)) {
7931                 /* TODO: improve error message */
7932                 errorf(&expression->base.source_position,
7933                        "operation needs an arithmetic or pointer type");
7934                 return;
7935         }
7936         if (!is_lvalue(expression->value)) {
7937                 /* TODO: improve error message */
7938                 errorf(&expression->base.source_position, "lvalue required as operand");
7939         }
7940         expression->base.type = orig_type;
7941 }
7942
7943 static void semantic_unexpr_arithmetic(unary_expression_t *expression)
7944 {
7945         type_t *const orig_type = expression->value->base.type;
7946         type_t *const type      = skip_typeref(orig_type);
7947         if (!is_type_arithmetic(type)) {
7948                 if (is_type_valid(type)) {
7949                         /* TODO: improve error message */
7950                         errorf(&expression->base.source_position,
7951                                 "operation needs an arithmetic type");
7952                 }
7953                 return;
7954         }
7955
7956         expression->base.type = orig_type;
7957 }
7958
7959 static void semantic_unexpr_plus(unary_expression_t *expression)
7960 {
7961         semantic_unexpr_arithmetic(expression);
7962         if (warning.traditional)
7963                 warningf(&expression->base.source_position,
7964                         "traditional C rejects the unary plus operator");
7965 }
7966
7967 static void semantic_not(unary_expression_t *expression)
7968 {
7969         /* §6.5.3.3:1  The operand [...] of the ! operator, scalar type. */
7970         semantic_condition(expression->value, "operand of !");
7971         expression->base.type = c_mode & _CXX ? type_bool : type_int;
7972 }
7973
7974 static void semantic_unexpr_integer(unary_expression_t *expression)
7975 {
7976         type_t *const orig_type = expression->value->base.type;
7977         type_t *const type      = skip_typeref(orig_type);
7978         if (!is_type_integer(type)) {
7979                 if (is_type_valid(type)) {
7980                         errorf(&expression->base.source_position,
7981                                "operand of ~ must be of integer type");
7982                 }
7983                 return;
7984         }
7985
7986         expression->base.type = orig_type;
7987 }
7988
7989 static void semantic_dereference(unary_expression_t *expression)
7990 {
7991         type_t *const orig_type = expression->value->base.type;
7992         type_t *const type      = skip_typeref(orig_type);
7993         if (!is_type_pointer(type)) {
7994                 if (is_type_valid(type)) {
7995                         errorf(&expression->base.source_position,
7996                                "Unary '*' needs pointer or array type, but type '%T' given", orig_type);
7997                 }
7998                 return;
7999         }
8000
8001         type_t *result_type   = type->pointer.points_to;
8002         result_type           = automatic_type_conversion(result_type);
8003         expression->base.type = result_type;
8004 }
8005
8006 /**
8007  * Record that an address is taken (expression represents an lvalue).
8008  *
8009  * @param expression       the expression
8010  * @param may_be_register  if true, the expression might be an register
8011  */
8012 static void set_address_taken(expression_t *expression, bool may_be_register)
8013 {
8014         if (expression->kind != EXPR_REFERENCE)
8015                 return;
8016
8017         entity_t *const entity = expression->reference.entity;
8018
8019         if (entity->kind != ENTITY_VARIABLE && entity->kind != ENTITY_PARAMETER)
8020                 return;
8021
8022         if (entity->declaration.storage_class == STORAGE_CLASS_REGISTER
8023                         && !may_be_register) {
8024                 errorf(&expression->base.source_position,
8025                                 "address of register %s '%Y' requested",
8026                                 get_entity_kind_name(entity->kind),     entity->base.symbol);
8027         }
8028
8029         if (entity->kind == ENTITY_VARIABLE) {
8030                 entity->variable.address_taken = true;
8031         } else {
8032                 assert(entity->kind == ENTITY_PARAMETER);
8033                 entity->parameter.address_taken = true;
8034         }
8035 }
8036
8037 /**
8038  * Check the semantic of the address taken expression.
8039  */
8040 static void semantic_take_addr(unary_expression_t *expression)
8041 {
8042         expression_t *value = expression->value;
8043         value->base.type    = revert_automatic_type_conversion(value);
8044
8045         type_t *orig_type = value->base.type;
8046         type_t *type      = skip_typeref(orig_type);
8047         if (!is_type_valid(type))
8048                 return;
8049
8050         /* §6.5.3.2 */
8051         if (!is_lvalue(value)) {
8052                 errorf(&expression->base.source_position, "'&' requires an lvalue");
8053         }
8054         if (type->kind == TYPE_BITFIELD) {
8055                 errorf(&expression->base.source_position,
8056                        "'&' not allowed on object with bitfield type '%T'",
8057                        type);
8058         }
8059
8060         set_address_taken(value, false);
8061
8062         expression->base.type = make_pointer_type(orig_type, TYPE_QUALIFIER_NONE);
8063 }
8064
8065 #define CREATE_UNARY_EXPRESSION_PARSER(token_type, unexpression_type, sfunc) \
8066 static expression_t *parse_##unexpression_type(void)                         \
8067 {                                                                            \
8068         expression_t *unary_expression                                           \
8069                 = allocate_expression_zero(unexpression_type);                       \
8070         eat(token_type);                                                         \
8071         unary_expression->unary.value = parse_sub_expression(PREC_UNARY);        \
8072                                                                                  \
8073         sfunc(&unary_expression->unary);                                         \
8074                                                                                  \
8075         return unary_expression;                                                 \
8076 }
8077
8078 CREATE_UNARY_EXPRESSION_PARSER('-', EXPR_UNARY_NEGATE,
8079                                semantic_unexpr_arithmetic)
8080 CREATE_UNARY_EXPRESSION_PARSER('+', EXPR_UNARY_PLUS,
8081                                semantic_unexpr_plus)
8082 CREATE_UNARY_EXPRESSION_PARSER('!', EXPR_UNARY_NOT,
8083                                semantic_not)
8084 CREATE_UNARY_EXPRESSION_PARSER('*', EXPR_UNARY_DEREFERENCE,
8085                                semantic_dereference)
8086 CREATE_UNARY_EXPRESSION_PARSER('&', EXPR_UNARY_TAKE_ADDRESS,
8087                                semantic_take_addr)
8088 CREATE_UNARY_EXPRESSION_PARSER('~', EXPR_UNARY_BITWISE_NEGATE,
8089                                semantic_unexpr_integer)
8090 CREATE_UNARY_EXPRESSION_PARSER(T_PLUSPLUS,   EXPR_UNARY_PREFIX_INCREMENT,
8091                                semantic_incdec)
8092 CREATE_UNARY_EXPRESSION_PARSER(T_MINUSMINUS, EXPR_UNARY_PREFIX_DECREMENT,
8093                                semantic_incdec)
8094
8095 #define CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(token_type, unexpression_type, \
8096                                                sfunc)                         \
8097 static expression_t *parse_##unexpression_type(expression_t *left)            \
8098 {                                                                             \
8099         expression_t *unary_expression                                            \
8100                 = allocate_expression_zero(unexpression_type);                        \
8101         eat(token_type);                                                          \
8102         unary_expression->unary.value = left;                                     \
8103                                                                                   \
8104         sfunc(&unary_expression->unary);                                          \
8105                                                                               \
8106         return unary_expression;                                                  \
8107 }
8108
8109 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_PLUSPLUS,
8110                                        EXPR_UNARY_POSTFIX_INCREMENT,
8111                                        semantic_incdec)
8112 CREATE_UNARY_POSTFIX_EXPRESSION_PARSER(T_MINUSMINUS,
8113                                        EXPR_UNARY_POSTFIX_DECREMENT,
8114                                        semantic_incdec)
8115
8116 static type_t *semantic_arithmetic(type_t *type_left, type_t *type_right)
8117 {
8118         /* TODO: handle complex + imaginary types */
8119
8120         type_left  = get_unqualified_type(type_left);
8121         type_right = get_unqualified_type(type_right);
8122
8123         /* §6.3.1.8 Usual arithmetic conversions */
8124         if (type_left == type_long_double || type_right == type_long_double) {
8125                 return type_long_double;
8126         } else if (type_left == type_double || type_right == type_double) {
8127                 return type_double;
8128         } else if (type_left == type_float || type_right == type_float) {
8129                 return type_float;
8130         }
8131
8132         type_left  = promote_integer(type_left);
8133         type_right = promote_integer(type_right);
8134
8135         if (type_left == type_right)
8136                 return type_left;
8137
8138         bool const signed_left  = is_type_signed(type_left);
8139         bool const signed_right = is_type_signed(type_right);
8140         int const  rank_left    = get_rank(type_left);
8141         int const  rank_right   = get_rank(type_right);
8142
8143         if (signed_left == signed_right)
8144                 return rank_left >= rank_right ? type_left : type_right;
8145
8146         int     s_rank;
8147         int     u_rank;
8148         type_t *s_type;
8149         type_t *u_type;
8150         if (signed_left) {
8151                 s_rank = rank_left;
8152                 s_type = type_left;
8153                 u_rank = rank_right;
8154                 u_type = type_right;
8155         } else {
8156                 s_rank = rank_right;
8157                 s_type = type_right;
8158                 u_rank = rank_left;
8159                 u_type = type_left;
8160         }
8161
8162         if (u_rank >= s_rank)
8163                 return u_type;
8164
8165         /* casting rank to atomic_type_kind is a bit hacky, but makes things
8166          * easier here... */
8167         if (get_atomic_type_size((atomic_type_kind_t) s_rank)
8168                         > get_atomic_type_size((atomic_type_kind_t) u_rank))
8169                 return s_type;
8170
8171         switch (s_rank) {
8172                 case ATOMIC_TYPE_INT:      return type_unsigned_int;
8173                 case ATOMIC_TYPE_LONG:     return type_unsigned_long;
8174                 case ATOMIC_TYPE_LONGLONG: return type_unsigned_long_long;
8175
8176                 default: panic("invalid atomic type");
8177         }
8178 }
8179
8180 /**
8181  * Check the semantic restrictions for a binary expression.
8182  */
8183 static void semantic_binexpr_arithmetic(binary_expression_t *expression)
8184 {
8185         expression_t *const left            = expression->left;
8186         expression_t *const right           = expression->right;
8187         type_t       *const orig_type_left  = left->base.type;
8188         type_t       *const orig_type_right = right->base.type;
8189         type_t       *const type_left       = skip_typeref(orig_type_left);
8190         type_t       *const type_right      = skip_typeref(orig_type_right);
8191
8192         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8193                 /* TODO: improve error message */
8194                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8195                         errorf(&expression->base.source_position,
8196                                "operation needs arithmetic types");
8197                 }
8198                 return;
8199         }
8200
8201         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8202         expression->left      = create_implicit_cast(left, arithmetic_type);
8203         expression->right     = create_implicit_cast(right, arithmetic_type);
8204         expression->base.type = arithmetic_type;
8205 }
8206
8207 static void warn_div_by_zero(binary_expression_t const *const expression)
8208 {
8209         if (!warning.div_by_zero ||
8210             !is_type_integer(expression->base.type))
8211                 return;
8212
8213         expression_t const *const right = expression->right;
8214         /* The type of the right operand can be different for /= */
8215         if (is_type_integer(right->base.type) &&
8216             is_constant_expression(right)     &&
8217             !fold_constant_to_bool(right)) {
8218                 warningf(&expression->base.source_position, "division by zero");
8219         }
8220 }
8221
8222 /**
8223  * Check the semantic restrictions for a div/mod expression.
8224  */
8225 static void semantic_divmod_arithmetic(binary_expression_t *expression)
8226 {
8227         semantic_binexpr_arithmetic(expression);
8228         warn_div_by_zero(expression);
8229 }
8230
8231 static void warn_addsub_in_shift(const expression_t *const expr)
8232 {
8233         if (expr->base.parenthesized)
8234                 return;
8235
8236         char op;
8237         switch (expr->kind) {
8238                 case EXPR_BINARY_ADD: op = '+'; break;
8239                 case EXPR_BINARY_SUB: op = '-'; break;
8240                 default:              return;
8241         }
8242
8243         warningf(&expr->base.source_position,
8244                         "suggest parentheses around '%c' inside shift", op);
8245 }
8246
8247 static bool semantic_shift(binary_expression_t *expression)
8248 {
8249         expression_t *const left            = expression->left;
8250         expression_t *const right           = expression->right;
8251         type_t       *const orig_type_left  = left->base.type;
8252         type_t       *const orig_type_right = right->base.type;
8253         type_t       *      type_left       = skip_typeref(orig_type_left);
8254         type_t       *      type_right      = skip_typeref(orig_type_right);
8255
8256         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8257                 /* TODO: improve error message */
8258                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8259                         errorf(&expression->base.source_position,
8260                                "operands of shift operation must have integer types");
8261                 }
8262                 return false;
8263         }
8264
8265         type_left = promote_integer(type_left);
8266
8267         if (is_constant_expression(right)) {
8268                 long count = fold_constant_to_int(right);
8269                 if (count < 0) {
8270                         warningf(&right->base.source_position,
8271                                         "shift count must be non-negative");
8272                 } else if ((unsigned long)count >=
8273                                 get_atomic_type_size(type_left->atomic.akind) * 8) {
8274                         warningf(&right->base.source_position,
8275                                         "shift count must be less than type width");
8276                 }
8277         }
8278
8279         type_right        = promote_integer(type_right);
8280         expression->right = create_implicit_cast(right, type_right);
8281
8282         return true;
8283 }
8284
8285 static void semantic_shift_op(binary_expression_t *expression)
8286 {
8287         expression_t *const left  = expression->left;
8288         expression_t *const right = expression->right;
8289
8290         if (!semantic_shift(expression))
8291                 return;
8292
8293         if (warning.parentheses) {
8294                 warn_addsub_in_shift(left);
8295                 warn_addsub_in_shift(right);
8296         }
8297
8298         type_t *const orig_type_left = left->base.type;
8299         type_t *      type_left      = skip_typeref(orig_type_left);
8300
8301         type_left             = promote_integer(type_left);
8302         expression->left      = create_implicit_cast(left, type_left);
8303         expression->base.type = type_left;
8304 }
8305
8306 static void semantic_add(binary_expression_t *expression)
8307 {
8308         expression_t *const left            = expression->left;
8309         expression_t *const right           = expression->right;
8310         type_t       *const orig_type_left  = left->base.type;
8311         type_t       *const orig_type_right = right->base.type;
8312         type_t       *const type_left       = skip_typeref(orig_type_left);
8313         type_t       *const type_right      = skip_typeref(orig_type_right);
8314
8315         /* §6.5.6 */
8316         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8317                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8318                 expression->left  = create_implicit_cast(left, arithmetic_type);
8319                 expression->right = create_implicit_cast(right, arithmetic_type);
8320                 expression->base.type = arithmetic_type;
8321         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8322                 check_pointer_arithmetic(&expression->base.source_position,
8323                                          type_left, orig_type_left);
8324                 expression->base.type = type_left;
8325         } else if (is_type_pointer(type_right) && is_type_integer(type_left)) {
8326                 check_pointer_arithmetic(&expression->base.source_position,
8327                                          type_right, orig_type_right);
8328                 expression->base.type = type_right;
8329         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8330                 errorf(&expression->base.source_position,
8331                        "invalid operands to binary + ('%T', '%T')",
8332                        orig_type_left, orig_type_right);
8333         }
8334 }
8335
8336 static void semantic_sub(binary_expression_t *expression)
8337 {
8338         expression_t            *const left            = expression->left;
8339         expression_t            *const right           = expression->right;
8340         type_t                  *const orig_type_left  = left->base.type;
8341         type_t                  *const orig_type_right = right->base.type;
8342         type_t                  *const type_left       = skip_typeref(orig_type_left);
8343         type_t                  *const type_right      = skip_typeref(orig_type_right);
8344         source_position_t const *const pos             = &expression->base.source_position;
8345
8346         /* §5.6.5 */
8347         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8348                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8349                 expression->left        = create_implicit_cast(left, arithmetic_type);
8350                 expression->right       = create_implicit_cast(right, arithmetic_type);
8351                 expression->base.type =  arithmetic_type;
8352         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8353                 check_pointer_arithmetic(&expression->base.source_position,
8354                                          type_left, orig_type_left);
8355                 expression->base.type = type_left;
8356         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8357                 type_t *const unqual_left  = get_unqualified_type(skip_typeref(type_left->pointer.points_to));
8358                 type_t *const unqual_right = get_unqualified_type(skip_typeref(type_right->pointer.points_to));
8359                 if (!types_compatible(unqual_left, unqual_right)) {
8360                         errorf(pos,
8361                                "subtracting pointers to incompatible types '%T' and '%T'",
8362                                orig_type_left, orig_type_right);
8363                 } else if (!is_type_object(unqual_left)) {
8364                         if (!is_type_atomic(unqual_left, ATOMIC_TYPE_VOID)) {
8365                                 errorf(pos, "subtracting pointers to non-object types '%T'",
8366                                        orig_type_left);
8367                         } else if (warning.other) {
8368                                 warningf(pos, "subtracting pointers to void");
8369                         }
8370                 }
8371                 expression->base.type = type_ptrdiff_t;
8372         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8373                 errorf(pos, "invalid operands of types '%T' and '%T' to binary '-'",
8374                        orig_type_left, orig_type_right);
8375         }
8376 }
8377
8378 static void warn_string_literal_address(expression_t const* expr)
8379 {
8380         while (expr->kind == EXPR_UNARY_TAKE_ADDRESS) {
8381                 expr = expr->unary.value;
8382                 if (expr->kind != EXPR_UNARY_DEREFERENCE)
8383                         return;
8384                 expr = expr->unary.value;
8385         }
8386
8387         if (expr->kind == EXPR_STRING_LITERAL
8388                         || expr->kind == EXPR_WIDE_STRING_LITERAL) {
8389                 warningf(&expr->base.source_position,
8390                         "comparison with string literal results in unspecified behaviour");
8391         }
8392 }
8393
8394 static void warn_comparison_in_comparison(const expression_t *const expr)
8395 {
8396         if (expr->base.parenthesized)
8397                 return;
8398         switch (expr->base.kind) {
8399                 case EXPR_BINARY_LESS:
8400                 case EXPR_BINARY_GREATER:
8401                 case EXPR_BINARY_LESSEQUAL:
8402                 case EXPR_BINARY_GREATEREQUAL:
8403                 case EXPR_BINARY_NOTEQUAL:
8404                 case EXPR_BINARY_EQUAL:
8405                         warningf(&expr->base.source_position,
8406                                         "comparisons like 'x <= y < z' do not have their mathematical meaning");
8407                         break;
8408                 default:
8409                         break;
8410         }
8411 }
8412
8413 static bool maybe_negative(expression_t const *const expr)
8414 {
8415         return
8416                 !is_constant_expression(expr) ||
8417                 fold_constant_to_int(expr) < 0;
8418 }
8419
8420 /**
8421  * Check the semantics of comparison expressions.
8422  *
8423  * @param expression   The expression to check.
8424  */
8425 static void semantic_comparison(binary_expression_t *expression)
8426 {
8427         expression_t *left  = expression->left;
8428         expression_t *right = expression->right;
8429
8430         if (warning.address) {
8431                 warn_string_literal_address(left);
8432                 warn_string_literal_address(right);
8433
8434                 expression_t const* const func_left = get_reference_address(left);
8435                 if (func_left != NULL && is_null_pointer_constant(right)) {
8436                         warningf(&expression->base.source_position,
8437                                  "the address of '%Y' will never be NULL",
8438                                  func_left->reference.entity->base.symbol);
8439                 }
8440
8441                 expression_t const* const func_right = get_reference_address(right);
8442                 if (func_right != NULL && is_null_pointer_constant(right)) {
8443                         warningf(&expression->base.source_position,
8444                                  "the address of '%Y' will never be NULL",
8445                                  func_right->reference.entity->base.symbol);
8446                 }
8447         }
8448
8449         if (warning.parentheses) {
8450                 warn_comparison_in_comparison(left);
8451                 warn_comparison_in_comparison(right);
8452         }
8453
8454         type_t *orig_type_left  = left->base.type;
8455         type_t *orig_type_right = right->base.type;
8456         type_t *type_left       = skip_typeref(orig_type_left);
8457         type_t *type_right      = skip_typeref(orig_type_right);
8458
8459         /* TODO non-arithmetic types */
8460         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8461                 type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8462
8463                 /* test for signed vs unsigned compares */
8464                 if (warning.sign_compare && is_type_integer(arithmetic_type)) {
8465                         bool const signed_left  = is_type_signed(type_left);
8466                         bool const signed_right = is_type_signed(type_right);
8467                         if (signed_left != signed_right) {
8468                                 /* FIXME long long needs better const folding magic */
8469                                 /* TODO check whether constant value can be represented by other type */
8470                                 if ((signed_left  && maybe_negative(left)) ||
8471                                                 (signed_right && maybe_negative(right))) {
8472                                         warningf(&expression->base.source_position,
8473                                                         "comparison between signed and unsigned");
8474                                 }
8475                         }
8476                 }
8477
8478                 expression->left        = create_implicit_cast(left, arithmetic_type);
8479                 expression->right       = create_implicit_cast(right, arithmetic_type);
8480                 expression->base.type   = arithmetic_type;
8481                 if (warning.float_equal &&
8482                     (expression->base.kind == EXPR_BINARY_EQUAL ||
8483                      expression->base.kind == EXPR_BINARY_NOTEQUAL) &&
8484                     is_type_float(arithmetic_type)) {
8485                         warningf(&expression->base.source_position,
8486                                  "comparing floating point with == or != is unsafe");
8487                 }
8488         } else if (is_type_pointer(type_left) && is_type_pointer(type_right)) {
8489                 /* TODO check compatibility */
8490         } else if (is_type_pointer(type_left)) {
8491                 expression->right = create_implicit_cast(right, type_left);
8492         } else if (is_type_pointer(type_right)) {
8493                 expression->left = create_implicit_cast(left, type_right);
8494         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8495                 type_error_incompatible("invalid operands in comparison",
8496                                         &expression->base.source_position,
8497                                         type_left, type_right);
8498         }
8499         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8500 }
8501
8502 /**
8503  * Checks if a compound type has constant fields.
8504  */
8505 static bool has_const_fields(const compound_type_t *type)
8506 {
8507         compound_t *compound = type->compound;
8508         entity_t   *entry    = compound->members.entities;
8509
8510         for (; entry != NULL; entry = entry->base.next) {
8511                 if (!is_declaration(entry))
8512                         continue;
8513
8514                 const type_t *decl_type = skip_typeref(entry->declaration.type);
8515                 if (decl_type->base.qualifiers & TYPE_QUALIFIER_CONST)
8516                         return true;
8517         }
8518
8519         return false;
8520 }
8521
8522 static bool is_valid_assignment_lhs(expression_t const* const left)
8523 {
8524         type_t *const orig_type_left = revert_automatic_type_conversion(left);
8525         type_t *const type_left      = skip_typeref(orig_type_left);
8526
8527         if (!is_lvalue(left)) {
8528                 errorf(HERE, "left hand side '%E' of assignment is not an lvalue",
8529                        left);
8530                 return false;
8531         }
8532
8533         if (left->kind == EXPR_REFERENCE
8534                         && left->reference.entity->kind == ENTITY_FUNCTION) {
8535                 errorf(HERE, "cannot assign to function '%E'", left);
8536                 return false;
8537         }
8538
8539         if (is_type_array(type_left)) {
8540                 errorf(HERE, "cannot assign to array '%E'", left);
8541                 return false;
8542         }
8543         if (type_left->base.qualifiers & TYPE_QUALIFIER_CONST) {
8544                 errorf(HERE, "assignment to readonly location '%E' (type '%T')", left,
8545                        orig_type_left);
8546                 return false;
8547         }
8548         if (is_type_incomplete(type_left)) {
8549                 errorf(HERE, "left-hand side '%E' of assignment has incomplete type '%T'",
8550                        left, orig_type_left);
8551                 return false;
8552         }
8553         if (is_type_compound(type_left) && has_const_fields(&type_left->compound)) {
8554                 errorf(HERE, "cannot assign to '%E' because compound type '%T' has readonly fields",
8555                        left, orig_type_left);
8556                 return false;
8557         }
8558
8559         return true;
8560 }
8561
8562 static void semantic_arithmetic_assign(binary_expression_t *expression)
8563 {
8564         expression_t *left            = expression->left;
8565         expression_t *right           = expression->right;
8566         type_t       *orig_type_left  = left->base.type;
8567         type_t       *orig_type_right = right->base.type;
8568
8569         if (!is_valid_assignment_lhs(left))
8570                 return;
8571
8572         type_t *type_left  = skip_typeref(orig_type_left);
8573         type_t *type_right = skip_typeref(orig_type_right);
8574
8575         if (!is_type_arithmetic(type_left) || !is_type_arithmetic(type_right)) {
8576                 /* TODO: improve error message */
8577                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8578                         errorf(&expression->base.source_position,
8579                                "operation needs arithmetic types");
8580                 }
8581                 return;
8582         }
8583
8584         /* combined instructions are tricky. We can't create an implicit cast on
8585          * the left side, because we need the uncasted form for the store.
8586          * The ast2firm pass has to know that left_type must be right_type
8587          * for the arithmetic operation and create a cast by itself */
8588         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8589         expression->right       = create_implicit_cast(right, arithmetic_type);
8590         expression->base.type   = type_left;
8591 }
8592
8593 static void semantic_divmod_assign(binary_expression_t *expression)
8594 {
8595         semantic_arithmetic_assign(expression);
8596         warn_div_by_zero(expression);
8597 }
8598
8599 static void semantic_arithmetic_addsubb_assign(binary_expression_t *expression)
8600 {
8601         expression_t *const left            = expression->left;
8602         expression_t *const right           = expression->right;
8603         type_t       *const orig_type_left  = left->base.type;
8604         type_t       *const orig_type_right = right->base.type;
8605         type_t       *const type_left       = skip_typeref(orig_type_left);
8606         type_t       *const type_right      = skip_typeref(orig_type_right);
8607
8608         if (!is_valid_assignment_lhs(left))
8609                 return;
8610
8611         if (is_type_arithmetic(type_left) && is_type_arithmetic(type_right)) {
8612                 /* combined instructions are tricky. We can't create an implicit cast on
8613                  * the left side, because we need the uncasted form for the store.
8614                  * The ast2firm pass has to know that left_type must be right_type
8615                  * for the arithmetic operation and create a cast by itself */
8616                 type_t *const arithmetic_type = semantic_arithmetic(type_left, type_right);
8617                 expression->right     = create_implicit_cast(right, arithmetic_type);
8618                 expression->base.type = type_left;
8619         } else if (is_type_pointer(type_left) && is_type_integer(type_right)) {
8620                 check_pointer_arithmetic(&expression->base.source_position,
8621                                          type_left, orig_type_left);
8622                 expression->base.type = type_left;
8623         } else if (is_type_valid(type_left) && is_type_valid(type_right)) {
8624                 errorf(&expression->base.source_position,
8625                        "incompatible types '%T' and '%T' in assignment",
8626                        orig_type_left, orig_type_right);
8627         }
8628 }
8629
8630 static void semantic_integer_assign(binary_expression_t *expression)
8631 {
8632         expression_t *left            = expression->left;
8633         expression_t *right           = expression->right;
8634         type_t       *orig_type_left  = left->base.type;
8635         type_t       *orig_type_right = right->base.type;
8636
8637         if (!is_valid_assignment_lhs(left))
8638                 return;
8639
8640         type_t *type_left  = skip_typeref(orig_type_left);
8641         type_t *type_right = skip_typeref(orig_type_right);
8642
8643         if (!is_type_integer(type_left) || !is_type_integer(type_right)) {
8644                 /* TODO: improve error message */
8645                 if (is_type_valid(type_left) && is_type_valid(type_right)) {
8646                         errorf(&expression->base.source_position,
8647                                "operation needs integer types");
8648                 }
8649                 return;
8650         }
8651
8652         /* combined instructions are tricky. We can't create an implicit cast on
8653          * the left side, because we need the uncasted form for the store.
8654          * The ast2firm pass has to know that left_type must be right_type
8655          * for the arithmetic operation and create a cast by itself */
8656         type_t *arithmetic_type = semantic_arithmetic(type_left, type_right);
8657         expression->right       = create_implicit_cast(right, arithmetic_type);
8658         expression->base.type   = type_left;
8659 }
8660
8661 static void semantic_shift_assign(binary_expression_t *expression)
8662 {
8663         expression_t *left           = expression->left;
8664
8665         if (!is_valid_assignment_lhs(left))
8666                 return;
8667
8668         if (!semantic_shift(expression))
8669                 return;
8670
8671         expression->base.type = skip_typeref(left->base.type);
8672 }
8673
8674 static void warn_logical_and_within_or(const expression_t *const expr)
8675 {
8676         if (expr->base.kind != EXPR_BINARY_LOGICAL_AND)
8677                 return;
8678         if (expr->base.parenthesized)
8679                 return;
8680         warningf(&expr->base.source_position,
8681                         "suggest parentheses around && within ||");
8682 }
8683
8684 /**
8685  * Check the semantic restrictions of a logical expression.
8686  */
8687 static void semantic_logical_op(binary_expression_t *expression)
8688 {
8689         /* §6.5.13:2  Each of the operands shall have scalar type.
8690          * §6.5.14:2  Each of the operands shall have scalar type. */
8691         semantic_condition(expression->left,   "left operand of logical operator");
8692         semantic_condition(expression->right, "right operand of logical operator");
8693         if (expression->base.kind == EXPR_BINARY_LOGICAL_OR &&
8694                         warning.parentheses) {
8695                 warn_logical_and_within_or(expression->left);
8696                 warn_logical_and_within_or(expression->right);
8697         }
8698         expression->base.type = c_mode & _CXX ? type_bool : type_int;
8699 }
8700
8701 /**
8702  * Check the semantic restrictions of a binary assign expression.
8703  */
8704 static void semantic_binexpr_assign(binary_expression_t *expression)
8705 {
8706         expression_t *left           = expression->left;
8707         type_t       *orig_type_left = left->base.type;
8708
8709         if (!is_valid_assignment_lhs(left))
8710                 return;
8711
8712         assign_error_t error = semantic_assign(orig_type_left, expression->right);
8713         report_assign_error(error, orig_type_left, expression->right,
8714                         "assignment", &left->base.source_position);
8715         expression->right = create_implicit_cast(expression->right, orig_type_left);
8716         expression->base.type = orig_type_left;
8717 }
8718
8719 /**
8720  * Determine if the outermost operation (or parts thereof) of the given
8721  * expression has no effect in order to generate a warning about this fact.
8722  * Therefore in some cases this only examines some of the operands of the
8723  * expression (see comments in the function and examples below).
8724  * Examples:
8725  *   f() + 23;    // warning, because + has no effect
8726  *   x || f();    // no warning, because x controls execution of f()
8727  *   x ? y : f(); // warning, because y has no effect
8728  *   (void)x;     // no warning to be able to suppress the warning
8729  * This function can NOT be used for an "expression has definitely no effect"-
8730  * analysis. */
8731 static bool expression_has_effect(const expression_t *const expr)
8732 {
8733         switch (expr->kind) {
8734                 case EXPR_UNKNOWN:                    break;
8735                 case EXPR_INVALID:                    return true; /* do NOT warn */
8736                 case EXPR_REFERENCE:                  return false;
8737                 case EXPR_REFERENCE_ENUM_VALUE:       return false;
8738                 case EXPR_LABEL_ADDRESS:              return false;
8739
8740                 /* suppress the warning for microsoft __noop operations */
8741                 case EXPR_LITERAL_MS_NOOP:            return true;
8742                 case EXPR_LITERAL_BOOLEAN:
8743                 case EXPR_LITERAL_CHARACTER:
8744                 case EXPR_LITERAL_WIDE_CHARACTER:
8745                 case EXPR_LITERAL_INTEGER:
8746                 case EXPR_LITERAL_INTEGER_OCTAL:
8747                 case EXPR_LITERAL_INTEGER_HEXADECIMAL:
8748                 case EXPR_LITERAL_FLOATINGPOINT:
8749                 case EXPR_LITERAL_FLOATINGPOINT_HEXADECIMAL: return false;
8750                 case EXPR_STRING_LITERAL:             return false;
8751                 case EXPR_WIDE_STRING_LITERAL:        return false;
8752
8753                 case EXPR_CALL: {
8754                         const call_expression_t *const call = &expr->call;
8755                         if (call->function->kind != EXPR_REFERENCE)
8756                                 return true;
8757
8758                         switch (call->function->reference.entity->function.btk) {
8759                                 /* FIXME: which builtins have no effect? */
8760                                 default:                      return true;
8761                         }
8762                 }
8763
8764                 /* Generate the warning if either the left or right hand side of a
8765                  * conditional expression has no effect */
8766                 case EXPR_CONDITIONAL: {
8767                         conditional_expression_t const *const cond = &expr->conditional;
8768                         expression_t             const *const t    = cond->true_expression;
8769                         return
8770                                 (t == NULL || expression_has_effect(t)) &&
8771                                 expression_has_effect(cond->false_expression);
8772                 }
8773
8774                 case EXPR_SELECT:                     return false;
8775                 case EXPR_ARRAY_ACCESS:               return false;
8776                 case EXPR_SIZEOF:                     return false;
8777                 case EXPR_CLASSIFY_TYPE:              return false;
8778                 case EXPR_ALIGNOF:                    return false;
8779
8780                 case EXPR_FUNCNAME:                   return false;
8781                 case EXPR_BUILTIN_CONSTANT_P:         return false;
8782                 case EXPR_BUILTIN_TYPES_COMPATIBLE_P: return false;
8783                 case EXPR_OFFSETOF:                   return false;
8784                 case EXPR_VA_START:                   return true;
8785                 case EXPR_VA_ARG:                     return true;
8786                 case EXPR_VA_COPY:                    return true;
8787                 case EXPR_STATEMENT:                  return true; // TODO
8788                 case EXPR_COMPOUND_LITERAL:           return false;
8789
8790                 case EXPR_UNARY_NEGATE:               return false;
8791                 case EXPR_UNARY_PLUS:                 return false;
8792                 case EXPR_UNARY_BITWISE_NEGATE:       return false;
8793                 case EXPR_UNARY_NOT:                  return false;
8794                 case EXPR_UNARY_DEREFERENCE:          return false;
8795                 case EXPR_UNARY_TAKE_ADDRESS:         return false;
8796                 case EXPR_UNARY_POSTFIX_INCREMENT:    return true;
8797                 case EXPR_UNARY_POSTFIX_DECREMENT:    return true;
8798                 case EXPR_UNARY_PREFIX_INCREMENT:     return true;
8799                 case EXPR_UNARY_PREFIX_DECREMENT:     return true;
8800
8801                 /* Treat void casts as if they have an effect in order to being able to
8802                  * suppress the warning */
8803                 case EXPR_UNARY_CAST: {
8804                         type_t *const type = skip_typeref(expr->base.type);
8805                         return is_type_atomic(type, ATOMIC_TYPE_VOID);
8806                 }
8807
8808                 case EXPR_UNARY_CAST_IMPLICIT:        return true;
8809                 case EXPR_UNARY_ASSUME:               return true;
8810                 case EXPR_UNARY_DELETE:               return true;
8811                 case EXPR_UNARY_DELETE_ARRAY:         return true;
8812                 case EXPR_UNARY_THROW:                return true;
8813
8814                 case EXPR_BINARY_ADD:                 return false;
8815                 case EXPR_BINARY_SUB:                 return false;
8816                 case EXPR_BINARY_MUL:                 return false;
8817                 case EXPR_BINARY_DIV:                 return false;
8818                 case EXPR_BINARY_MOD:                 return false;
8819                 case EXPR_BINARY_EQUAL:               return false;
8820                 case EXPR_BINARY_NOTEQUAL:            return false;
8821                 case EXPR_BINARY_LESS:                return false;
8822                 case EXPR_BINARY_LESSEQUAL:           return false;
8823                 case EXPR_BINARY_GREATER:             return false;
8824                 case EXPR_BINARY_GREATEREQUAL:        return false;
8825                 case EXPR_BINARY_BITWISE_AND:         return false;
8826                 case EXPR_BINARY_BITWISE_OR:          return false;
8827                 case EXPR_BINARY_BITWISE_XOR:         return false;
8828                 case EXPR_BINARY_SHIFTLEFT:           return false;
8829                 case EXPR_BINARY_SHIFTRIGHT:          return false;
8830                 case EXPR_BINARY_ASSIGN:              return true;
8831                 case EXPR_BINARY_MUL_ASSIGN:          return true;
8832                 case EXPR_BINARY_DIV_ASSIGN:          return true;
8833                 case EXPR_BINARY_MOD_ASSIGN:          return true;
8834                 case EXPR_BINARY_ADD_ASSIGN:          return true;
8835                 case EXPR_BINARY_SUB_ASSIGN:          return true;
8836                 case EXPR_BINARY_SHIFTLEFT_ASSIGN:    return true;
8837                 case EXPR_BINARY_SHIFTRIGHT_ASSIGN:   return true;
8838                 case EXPR_BINARY_BITWISE_AND_ASSIGN:  return true;
8839                 case EXPR_BINARY_BITWISE_XOR_ASSIGN:  return true;
8840                 case EXPR_BINARY_BITWISE_OR_ASSIGN:   return true;
8841
8842                 /* Only examine the right hand side of && and ||, because the left hand
8843                  * side already has the effect of controlling the execution of the right
8844                  * hand side */
8845                 case EXPR_BINARY_LOGICAL_AND:
8846                 case EXPR_BINARY_LOGICAL_OR:
8847                 /* Only examine the right hand side of a comma expression, because the left
8848                  * hand side has a separate warning */
8849                 case EXPR_BINARY_COMMA:
8850                         return expression_has_effect(expr->binary.right);
8851
8852                 case EXPR_BINARY_ISGREATER:           return false;
8853                 case EXPR_BINARY_ISGREATEREQUAL:      return false;
8854                 case EXPR_BINARY_ISLESS:              return false;
8855                 case EXPR_BINARY_ISLESSEQUAL:         return false;
8856                 case EXPR_BINARY_ISLESSGREATER:       return false;
8857                 case EXPR_BINARY_ISUNORDERED:         return false;
8858         }
8859
8860         internal_errorf(HERE, "unexpected expression");
8861 }
8862
8863 static void semantic_comma(binary_expression_t *expression)
8864 {
8865         if (warning.unused_value) {
8866                 const expression_t *const left = expression->left;
8867                 if (!expression_has_effect(left)) {
8868                         warningf(&left->base.source_position,
8869                                  "left-hand operand of comma expression has no effect");
8870                 }
8871         }
8872         expression->base.type = expression->right->base.type;
8873 }
8874
8875 /**
8876  * @param prec_r precedence of the right operand
8877  */
8878 #define CREATE_BINEXPR_PARSER(token_type, binexpression_type, prec_r, sfunc) \
8879 static expression_t *parse_##binexpression_type(expression_t *left)          \
8880 {                                                                            \
8881         expression_t *binexpr = allocate_expression_zero(binexpression_type);    \
8882         binexpr->binary.left  = left;                                            \
8883         eat(token_type);                                                         \
8884                                                                              \
8885         expression_t *right = parse_sub_expression(prec_r);                      \
8886                                                                              \
8887         binexpr->binary.right = right;                                           \
8888         sfunc(&binexpr->binary);                                                 \
8889                                                                              \
8890         return binexpr;                                                          \
8891 }
8892
8893 CREATE_BINEXPR_PARSER('*',                    EXPR_BINARY_MUL,                PREC_CAST,           semantic_binexpr_arithmetic)
8894 CREATE_BINEXPR_PARSER('/',                    EXPR_BINARY_DIV,                PREC_CAST,           semantic_divmod_arithmetic)
8895 CREATE_BINEXPR_PARSER('%',                    EXPR_BINARY_MOD,                PREC_CAST,           semantic_divmod_arithmetic)
8896 CREATE_BINEXPR_PARSER('+',                    EXPR_BINARY_ADD,                PREC_MULTIPLICATIVE, semantic_add)
8897 CREATE_BINEXPR_PARSER('-',                    EXPR_BINARY_SUB,                PREC_MULTIPLICATIVE, semantic_sub)
8898 CREATE_BINEXPR_PARSER(T_LESSLESS,             EXPR_BINARY_SHIFTLEFT,          PREC_ADDITIVE,       semantic_shift_op)
8899 CREATE_BINEXPR_PARSER(T_GREATERGREATER,       EXPR_BINARY_SHIFTRIGHT,         PREC_ADDITIVE,       semantic_shift_op)
8900 CREATE_BINEXPR_PARSER('<',                    EXPR_BINARY_LESS,               PREC_SHIFT,          semantic_comparison)
8901 CREATE_BINEXPR_PARSER('>',                    EXPR_BINARY_GREATER,            PREC_SHIFT,          semantic_comparison)
8902 CREATE_BINEXPR_PARSER(T_LESSEQUAL,            EXPR_BINARY_LESSEQUAL,          PREC_SHIFT,          semantic_comparison)
8903 CREATE_BINEXPR_PARSER(T_GREATEREQUAL,         EXPR_BINARY_GREATEREQUAL,       PREC_SHIFT,          semantic_comparison)
8904 CREATE_BINEXPR_PARSER(T_EXCLAMATIONMARKEQUAL, EXPR_BINARY_NOTEQUAL,           PREC_RELATIONAL,     semantic_comparison)
8905 CREATE_BINEXPR_PARSER(T_EQUALEQUAL,           EXPR_BINARY_EQUAL,              PREC_RELATIONAL,     semantic_comparison)
8906 CREATE_BINEXPR_PARSER('&',                    EXPR_BINARY_BITWISE_AND,        PREC_EQUALITY,       semantic_binexpr_arithmetic)
8907 CREATE_BINEXPR_PARSER('^',                    EXPR_BINARY_BITWISE_XOR,        PREC_AND,            semantic_binexpr_arithmetic)
8908 CREATE_BINEXPR_PARSER('|',                    EXPR_BINARY_BITWISE_OR,         PREC_XOR,            semantic_binexpr_arithmetic)
8909 CREATE_BINEXPR_PARSER(T_ANDAND,               EXPR_BINARY_LOGICAL_AND,        PREC_OR,             semantic_logical_op)
8910 CREATE_BINEXPR_PARSER(T_PIPEPIPE,             EXPR_BINARY_LOGICAL_OR,         PREC_LOGICAL_AND,    semantic_logical_op)
8911 CREATE_BINEXPR_PARSER('=',                    EXPR_BINARY_ASSIGN,             PREC_ASSIGNMENT,     semantic_binexpr_assign)
8912 CREATE_BINEXPR_PARSER(T_PLUSEQUAL,            EXPR_BINARY_ADD_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
8913 CREATE_BINEXPR_PARSER(T_MINUSEQUAL,           EXPR_BINARY_SUB_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_addsubb_assign)
8914 CREATE_BINEXPR_PARSER(T_ASTERISKEQUAL,        EXPR_BINARY_MUL_ASSIGN,         PREC_ASSIGNMENT,     semantic_arithmetic_assign)
8915 CREATE_BINEXPR_PARSER(T_SLASHEQUAL,           EXPR_BINARY_DIV_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
8916 CREATE_BINEXPR_PARSER(T_PERCENTEQUAL,         EXPR_BINARY_MOD_ASSIGN,         PREC_ASSIGNMENT,     semantic_divmod_assign)
8917 CREATE_BINEXPR_PARSER(T_LESSLESSEQUAL,        EXPR_BINARY_SHIFTLEFT_ASSIGN,   PREC_ASSIGNMENT,     semantic_shift_assign)
8918 CREATE_BINEXPR_PARSER(T_GREATERGREATEREQUAL,  EXPR_BINARY_SHIFTRIGHT_ASSIGN,  PREC_ASSIGNMENT,     semantic_shift_assign)
8919 CREATE_BINEXPR_PARSER(T_ANDEQUAL,             EXPR_BINARY_BITWISE_AND_ASSIGN, PREC_ASSIGNMENT,     semantic_integer_assign)
8920 CREATE_BINEXPR_PARSER(T_PIPEEQUAL,            EXPR_BINARY_BITWISE_OR_ASSIGN,  PREC_ASSIGNMENT,     semantic_integer_assign)
8921 CREATE_BINEXPR_PARSER(T_CARETEQUAL,           EXPR_BINARY_BITWISE_XOR_ASSIGN, PREC_ASSIGNMENT,     semantic_integer_assign)
8922 CREATE_BINEXPR_PARSER(',',                    EXPR_BINARY_COMMA,              PREC_ASSIGNMENT,     semantic_comma)
8923
8924
8925 static expression_t *parse_sub_expression(precedence_t precedence)
8926 {
8927         if (token.type < 0) {
8928                 return expected_expression_error();
8929         }
8930
8931         expression_parser_function_t *parser
8932                 = &expression_parsers[token.type];
8933         source_position_t             source_position = token.source_position;
8934         expression_t                 *left;
8935
8936         if (parser->parser != NULL) {
8937                 left = parser->parser();
8938         } else {
8939                 left = parse_primary_expression();
8940         }
8941         assert(left != NULL);
8942         left->base.source_position = source_position;
8943
8944         while (true) {
8945                 if (token.type < 0) {
8946                         return expected_expression_error();
8947                 }
8948
8949                 parser = &expression_parsers[token.type];
8950                 if (parser->infix_parser == NULL)
8951                         break;
8952                 if (parser->infix_precedence < precedence)
8953                         break;
8954
8955                 left = parser->infix_parser(left);
8956
8957                 assert(left != NULL);
8958                 assert(left->kind != EXPR_UNKNOWN);
8959                 left->base.source_position = source_position;
8960         }
8961
8962         return left;
8963 }
8964
8965 /**
8966  * Parse an expression.
8967  */
8968 static expression_t *parse_expression(void)
8969 {
8970         return parse_sub_expression(PREC_EXPRESSION);
8971 }
8972
8973 /**
8974  * Register a parser for a prefix-like operator.
8975  *
8976  * @param parser      the parser function
8977  * @param token_type  the token type of the prefix token
8978  */
8979 static void register_expression_parser(parse_expression_function parser,
8980                                        int token_type)
8981 {
8982         expression_parser_function_t *entry = &expression_parsers[token_type];
8983
8984         if (entry->parser != NULL) {
8985                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
8986                 panic("trying to register multiple expression parsers for a token");
8987         }
8988         entry->parser = parser;
8989 }
8990
8991 /**
8992  * Register a parser for an infix operator with given precedence.
8993  *
8994  * @param parser      the parser function
8995  * @param token_type  the token type of the infix operator
8996  * @param precedence  the precedence of the operator
8997  */
8998 static void register_infix_parser(parse_expression_infix_function parser,
8999                 int token_type, precedence_t precedence)
9000 {
9001         expression_parser_function_t *entry = &expression_parsers[token_type];
9002
9003         if (entry->infix_parser != NULL) {
9004                 diagnosticf("for token '%k'\n", (token_type_t)token_type);
9005                 panic("trying to register multiple infix expression parsers for a "
9006                       "token");
9007         }
9008         entry->infix_parser     = parser;
9009         entry->infix_precedence = precedence;
9010 }
9011
9012 /**
9013  * Initialize the expression parsers.
9014  */
9015 static void init_expression_parsers(void)
9016 {
9017         memset(&expression_parsers, 0, sizeof(expression_parsers));
9018
9019         register_infix_parser(parse_array_expression,               '[',                    PREC_POSTFIX);
9020         register_infix_parser(parse_call_expression,                '(',                    PREC_POSTFIX);
9021         register_infix_parser(parse_select_expression,              '.',                    PREC_POSTFIX);
9022         register_infix_parser(parse_select_expression,              T_MINUSGREATER,         PREC_POSTFIX);
9023         register_infix_parser(parse_EXPR_UNARY_POSTFIX_INCREMENT,   T_PLUSPLUS,             PREC_POSTFIX);
9024         register_infix_parser(parse_EXPR_UNARY_POSTFIX_DECREMENT,   T_MINUSMINUS,           PREC_POSTFIX);
9025         register_infix_parser(parse_EXPR_BINARY_MUL,                '*',                    PREC_MULTIPLICATIVE);
9026         register_infix_parser(parse_EXPR_BINARY_DIV,                '/',                    PREC_MULTIPLICATIVE);
9027         register_infix_parser(parse_EXPR_BINARY_MOD,                '%',                    PREC_MULTIPLICATIVE);
9028         register_infix_parser(parse_EXPR_BINARY_ADD,                '+',                    PREC_ADDITIVE);
9029         register_infix_parser(parse_EXPR_BINARY_SUB,                '-',                    PREC_ADDITIVE);
9030         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT,          T_LESSLESS,             PREC_SHIFT);
9031         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT,         T_GREATERGREATER,       PREC_SHIFT);
9032         register_infix_parser(parse_EXPR_BINARY_LESS,               '<',                    PREC_RELATIONAL);
9033         register_infix_parser(parse_EXPR_BINARY_GREATER,            '>',                    PREC_RELATIONAL);
9034         register_infix_parser(parse_EXPR_BINARY_LESSEQUAL,          T_LESSEQUAL,            PREC_RELATIONAL);
9035         register_infix_parser(parse_EXPR_BINARY_GREATEREQUAL,       T_GREATEREQUAL,         PREC_RELATIONAL);
9036         register_infix_parser(parse_EXPR_BINARY_EQUAL,              T_EQUALEQUAL,           PREC_EQUALITY);
9037         register_infix_parser(parse_EXPR_BINARY_NOTEQUAL,           T_EXCLAMATIONMARKEQUAL, PREC_EQUALITY);
9038         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND,        '&',                    PREC_AND);
9039         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR,        '^',                    PREC_XOR);
9040         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR,         '|',                    PREC_OR);
9041         register_infix_parser(parse_EXPR_BINARY_LOGICAL_AND,        T_ANDAND,               PREC_LOGICAL_AND);
9042         register_infix_parser(parse_EXPR_BINARY_LOGICAL_OR,         T_PIPEPIPE,             PREC_LOGICAL_OR);
9043         register_infix_parser(parse_conditional_expression,         '?',                    PREC_CONDITIONAL);
9044         register_infix_parser(parse_EXPR_BINARY_ASSIGN,             '=',                    PREC_ASSIGNMENT);
9045         register_infix_parser(parse_EXPR_BINARY_ADD_ASSIGN,         T_PLUSEQUAL,            PREC_ASSIGNMENT);
9046         register_infix_parser(parse_EXPR_BINARY_SUB_ASSIGN,         T_MINUSEQUAL,           PREC_ASSIGNMENT);
9047         register_infix_parser(parse_EXPR_BINARY_MUL_ASSIGN,         T_ASTERISKEQUAL,        PREC_ASSIGNMENT);
9048         register_infix_parser(parse_EXPR_BINARY_DIV_ASSIGN,         T_SLASHEQUAL,           PREC_ASSIGNMENT);
9049         register_infix_parser(parse_EXPR_BINARY_MOD_ASSIGN,         T_PERCENTEQUAL,         PREC_ASSIGNMENT);
9050         register_infix_parser(parse_EXPR_BINARY_SHIFTLEFT_ASSIGN,   T_LESSLESSEQUAL,        PREC_ASSIGNMENT);
9051         register_infix_parser(parse_EXPR_BINARY_SHIFTRIGHT_ASSIGN,  T_GREATERGREATEREQUAL,  PREC_ASSIGNMENT);
9052         register_infix_parser(parse_EXPR_BINARY_BITWISE_AND_ASSIGN, T_ANDEQUAL,             PREC_ASSIGNMENT);
9053         register_infix_parser(parse_EXPR_BINARY_BITWISE_OR_ASSIGN,  T_PIPEEQUAL,            PREC_ASSIGNMENT);
9054         register_infix_parser(parse_EXPR_BINARY_BITWISE_XOR_ASSIGN, T_CARETEQUAL,           PREC_ASSIGNMENT);
9055         register_infix_parser(parse_EXPR_BINARY_COMMA,              ',',                    PREC_EXPRESSION);
9056
9057         register_expression_parser(parse_EXPR_UNARY_NEGATE,           '-');
9058         register_expression_parser(parse_EXPR_UNARY_PLUS,             '+');
9059         register_expression_parser(parse_EXPR_UNARY_NOT,              '!');
9060         register_expression_parser(parse_EXPR_UNARY_BITWISE_NEGATE,   '~');
9061         register_expression_parser(parse_EXPR_UNARY_DEREFERENCE,      '*');
9062         register_expression_parser(parse_EXPR_UNARY_TAKE_ADDRESS,     '&');
9063         register_expression_parser(parse_EXPR_UNARY_PREFIX_INCREMENT, T_PLUSPLUS);
9064         register_expression_parser(parse_EXPR_UNARY_PREFIX_DECREMENT, T_MINUSMINUS);
9065         register_expression_parser(parse_sizeof,                      T_sizeof);
9066         register_expression_parser(parse_alignof,                     T___alignof__);
9067         register_expression_parser(parse_extension,                   T___extension__);
9068         register_expression_parser(parse_builtin_classify_type,       T___builtin_classify_type);
9069         register_expression_parser(parse_delete,                      T_delete);
9070         register_expression_parser(parse_throw,                       T_throw);
9071 }
9072
9073 /**
9074  * Parse a asm statement arguments specification.
9075  */
9076 static asm_argument_t *parse_asm_arguments(bool is_out)
9077 {
9078         asm_argument_t  *result = NULL;
9079         asm_argument_t **anchor = &result;
9080
9081         while (token.type == T_STRING_LITERAL || token.type == '[') {
9082                 asm_argument_t *argument = allocate_ast_zero(sizeof(argument[0]));
9083                 memset(argument, 0, sizeof(argument[0]));
9084
9085                 if (next_if('[')) {
9086                         if (token.type != T_IDENTIFIER) {
9087                                 parse_error_expected("while parsing asm argument",
9088                                                      T_IDENTIFIER, NULL);
9089                                 return NULL;
9090                         }
9091                         argument->symbol = token.symbol;
9092
9093                         expect(']', end_error);
9094                 }
9095
9096                 argument->constraints = parse_string_literals();
9097                 expect('(', end_error);
9098                 add_anchor_token(')');
9099                 expression_t *expression = parse_expression();
9100                 rem_anchor_token(')');
9101                 if (is_out) {
9102                         /* Ugly GCC stuff: Allow lvalue casts.  Skip casts, when they do not
9103                          * change size or type representation (e.g. int -> long is ok, but
9104                          * int -> float is not) */
9105                         if (expression->kind == EXPR_UNARY_CAST) {
9106                                 type_t      *const type = expression->base.type;
9107                                 type_kind_t  const kind = type->kind;
9108                                 if (kind == TYPE_ATOMIC || kind == TYPE_POINTER) {
9109                                         unsigned flags;
9110                                         unsigned size;
9111                                         if (kind == TYPE_ATOMIC) {
9112                                                 atomic_type_kind_t const akind = type->atomic.akind;
9113                                                 flags = get_atomic_type_flags(akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9114                                                 size  = get_atomic_type_size(akind);
9115                                         } else {
9116                                                 flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9117                                                 size  = get_atomic_type_size(get_intptr_kind());
9118                                         }
9119
9120                                         do {
9121                                                 expression_t *const value      = expression->unary.value;
9122                                                 type_t       *const value_type = value->base.type;
9123                                                 type_kind_t   const value_kind = value_type->kind;
9124
9125                                                 unsigned value_flags;
9126                                                 unsigned value_size;
9127                                                 if (value_kind == TYPE_ATOMIC) {
9128                                                         atomic_type_kind_t const value_akind = value_type->atomic.akind;
9129                                                         value_flags = get_atomic_type_flags(value_akind) & ~ATOMIC_TYPE_FLAG_SIGNED;
9130                                                         value_size  = get_atomic_type_size(value_akind);
9131                                                 } else if (value_kind == TYPE_POINTER) {
9132                                                         value_flags = ATOMIC_TYPE_FLAG_INTEGER | ATOMIC_TYPE_FLAG_ARITHMETIC;
9133                                                         value_size  = get_atomic_type_size(get_intptr_kind());
9134                                                 } else {
9135                                                         break;
9136                                                 }
9137
9138                                                 if (value_flags != flags || value_size != size)
9139                                                         break;
9140
9141                                                 expression = value;
9142                                         } while (expression->kind == EXPR_UNARY_CAST);
9143                                 }
9144                         }
9145
9146                         if (!is_lvalue(expression)) {
9147                                 errorf(&expression->base.source_position,
9148                                        "asm output argument is not an lvalue");
9149                         }
9150
9151                         if (argument->constraints.begin[0] == '=')
9152                                 determine_lhs_ent(expression, NULL);
9153                         else
9154                                 mark_vars_read(expression, NULL);
9155                 } else {
9156                         mark_vars_read(expression, NULL);
9157                 }
9158                 argument->expression = expression;
9159                 expect(')', end_error);
9160
9161                 set_address_taken(expression, true);
9162
9163                 *anchor = argument;
9164                 anchor  = &argument->next;
9165
9166                 if (!next_if(','))
9167                         break;
9168         }
9169
9170         return result;
9171 end_error:
9172         return NULL;
9173 }
9174
9175 /**
9176  * Parse a asm statement clobber specification.
9177  */
9178 static asm_clobber_t *parse_asm_clobbers(void)
9179 {
9180         asm_clobber_t *result  = NULL;
9181         asm_clobber_t **anchor = &result;
9182
9183         while (token.type == T_STRING_LITERAL) {
9184                 asm_clobber_t *clobber = allocate_ast_zero(sizeof(clobber[0]));
9185                 clobber->clobber       = parse_string_literals();
9186
9187                 *anchor = clobber;
9188                 anchor  = &clobber->next;
9189
9190                 if (!next_if(','))
9191                         break;
9192         }
9193
9194         return result;
9195 }
9196
9197 /**
9198  * Parse an asm statement.
9199  */
9200 static statement_t *parse_asm_statement(void)
9201 {
9202         statement_t     *statement     = allocate_statement_zero(STATEMENT_ASM);
9203         asm_statement_t *asm_statement = &statement->asms;
9204
9205         eat(T_asm);
9206
9207         if (next_if(T_volatile))
9208                 asm_statement->is_volatile = true;
9209
9210         expect('(', end_error);
9211         add_anchor_token(')');
9212         add_anchor_token(':');
9213         asm_statement->asm_text = parse_string_literals();
9214
9215         if (!next_if(':')) {
9216                 rem_anchor_token(':');
9217                 goto end_of_asm;
9218         }
9219
9220         asm_statement->outputs = parse_asm_arguments(true);
9221         if (!next_if(':')) {
9222                 rem_anchor_token(':');
9223                 goto end_of_asm;
9224         }
9225
9226         asm_statement->inputs = parse_asm_arguments(false);
9227         if (!next_if(':')) {
9228                 rem_anchor_token(':');
9229                 goto end_of_asm;
9230         }
9231         rem_anchor_token(':');
9232
9233         asm_statement->clobbers = parse_asm_clobbers();
9234
9235 end_of_asm:
9236         rem_anchor_token(')');
9237         expect(')', end_error);
9238         expect(';', end_error);
9239
9240         if (asm_statement->outputs == NULL) {
9241                 /* GCC: An 'asm' instruction without any output operands will be treated
9242                  * identically to a volatile 'asm' instruction. */
9243                 asm_statement->is_volatile = true;
9244         }
9245
9246         return statement;
9247 end_error:
9248         return create_invalid_statement();
9249 }
9250
9251 /**
9252  * Parse a case statement.
9253  */
9254 static statement_t *parse_case_statement(void)
9255 {
9256         statement_t       *const statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9257         source_position_t *const pos       = &statement->base.source_position;
9258
9259         eat(T_case);
9260
9261         expression_t *const expression   = parse_expression();
9262         statement->case_label.expression = expression;
9263         if (!is_constant_expression(expression)) {
9264                 /* This check does not prevent the error message in all cases of an
9265                  * prior error while parsing the expression.  At least it catches the
9266                  * common case of a mistyped enum entry. */
9267                 if (is_type_valid(skip_typeref(expression->base.type))) {
9268                         errorf(pos, "case label does not reduce to an integer constant");
9269                 }
9270                 statement->case_label.is_bad = true;
9271         } else {
9272                 long const val = fold_constant_to_int(expression);
9273                 statement->case_label.first_case = val;
9274                 statement->case_label.last_case  = val;
9275         }
9276
9277         if (GNU_MODE) {
9278                 if (next_if(T_DOTDOTDOT)) {
9279                         expression_t *const end_range   = parse_expression();
9280                         statement->case_label.end_range = end_range;
9281                         if (!is_constant_expression(end_range)) {
9282                                 /* This check does not prevent the error message in all cases of an
9283                                  * prior error while parsing the expression.  At least it catches the
9284                                  * common case of a mistyped enum entry. */
9285                                 if (is_type_valid(skip_typeref(end_range->base.type))) {
9286                                         errorf(pos, "case range does not reduce to an integer constant");
9287                                 }
9288                                 statement->case_label.is_bad = true;
9289                         } else {
9290                                 long const val = fold_constant_to_int(end_range);
9291                                 statement->case_label.last_case = val;
9292
9293                                 if (warning.other && val < statement->case_label.first_case) {
9294                                         statement->case_label.is_empty_range = true;
9295                                         warningf(pos, "empty range specified");
9296                                 }
9297                         }
9298                 }
9299         }
9300
9301         PUSH_PARENT(statement);
9302
9303         expect(':', end_error);
9304 end_error:
9305
9306         if (current_switch != NULL) {
9307                 if (! statement->case_label.is_bad) {
9308                         /* Check for duplicate case values */
9309                         case_label_statement_t *c = &statement->case_label;
9310                         for (case_label_statement_t *l = current_switch->first_case; l != NULL; l = l->next) {
9311                                 if (l->is_bad || l->is_empty_range || l->expression == NULL)
9312                                         continue;
9313
9314                                 if (c->last_case < l->first_case || c->first_case > l->last_case)
9315                                         continue;
9316
9317                                 errorf(pos, "duplicate case value (previously used %P)",
9318                                        &l->base.source_position);
9319                                 break;
9320                         }
9321                 }
9322                 /* link all cases into the switch statement */
9323                 if (current_switch->last_case == NULL) {
9324                         current_switch->first_case      = &statement->case_label;
9325                 } else {
9326                         current_switch->last_case->next = &statement->case_label;
9327                 }
9328                 current_switch->last_case = &statement->case_label;
9329         } else {
9330                 errorf(pos, "case label not within a switch statement");
9331         }
9332
9333         statement_t *const inner_stmt = parse_statement();
9334         statement->case_label.statement = inner_stmt;
9335         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9336                 errorf(&inner_stmt->base.source_position, "declaration after case label");
9337         }
9338
9339         POP_PARENT;
9340         return statement;
9341 }
9342
9343 /**
9344  * Parse a default statement.
9345  */
9346 static statement_t *parse_default_statement(void)
9347 {
9348         statement_t *statement = allocate_statement_zero(STATEMENT_CASE_LABEL);
9349
9350         eat(T_default);
9351
9352         PUSH_PARENT(statement);
9353
9354         expect(':', end_error);
9355         if (current_switch != NULL) {
9356                 const case_label_statement_t *def_label = current_switch->default_label;
9357                 if (def_label != NULL) {
9358                         errorf(HERE, "multiple default labels in one switch (previous declared %P)",
9359                                &def_label->base.source_position);
9360                 } else {
9361                         current_switch->default_label = &statement->case_label;
9362
9363                         /* link all cases into the switch statement */
9364                         if (current_switch->last_case == NULL) {
9365                                 current_switch->first_case      = &statement->case_label;
9366                         } else {
9367                                 current_switch->last_case->next = &statement->case_label;
9368                         }
9369                         current_switch->last_case = &statement->case_label;
9370                 }
9371         } else {
9372                 errorf(&statement->base.source_position,
9373                         "'default' label not within a switch statement");
9374         }
9375
9376         statement_t *const inner_stmt = parse_statement();
9377         statement->case_label.statement = inner_stmt;
9378         if (inner_stmt->kind == STATEMENT_DECLARATION) {
9379                 errorf(&inner_stmt->base.source_position, "declaration after default label");
9380         }
9381
9382         POP_PARENT;
9383         return statement;
9384 end_error:
9385         POP_PARENT;
9386         return create_invalid_statement();
9387 }
9388
9389 /**
9390  * Parse a label statement.
9391  */
9392 static statement_t *parse_label_statement(void)
9393 {
9394         assert(token.type == T_IDENTIFIER);
9395         symbol_t *symbol = token.symbol;
9396         label_t  *label  = get_label(symbol);
9397
9398         statement_t *const statement = allocate_statement_zero(STATEMENT_LABEL);
9399         statement->label.label       = label;
9400
9401         next_token();
9402
9403         PUSH_PARENT(statement);
9404
9405         /* if statement is already set then the label is defined twice,
9406          * otherwise it was just mentioned in a goto/local label declaration so far
9407          */
9408         if (label->statement != NULL) {
9409                 errorf(HERE, "duplicate label '%Y' (declared %P)",
9410                        symbol, &label->base.source_position);
9411         } else {
9412                 label->base.source_position = token.source_position;
9413                 label->statement            = statement;
9414         }
9415
9416         eat(':');
9417
9418         if (token.type == '}') {
9419                 errorf(HERE, "label at end of compound statement");
9420                 statement->label.statement = create_invalid_statement();
9421         } else if (token.type == ';') {
9422                 /* Eat an empty statement here, to avoid the warning about an empty
9423                  * statement after a label.  label:; is commonly used to have a label
9424                  * before a closing brace. */
9425                 statement->label.statement = create_empty_statement();
9426                 next_token();
9427         } else {
9428                 statement_t *const inner_stmt = parse_statement();
9429                 statement->label.statement = inner_stmt;
9430                 if (inner_stmt->kind == STATEMENT_DECLARATION) {
9431                         errorf(&inner_stmt->base.source_position, "declaration after label");
9432                 }
9433         }
9434
9435         /* remember the labels in a list for later checking */
9436         *label_anchor = &statement->label;
9437         label_anchor  = &statement->label.next;
9438
9439         POP_PARENT;
9440         return statement;
9441 }
9442
9443 /**
9444  * Parse an if statement.
9445  */
9446 static statement_t *parse_if(void)
9447 {
9448         statement_t *statement = allocate_statement_zero(STATEMENT_IF);
9449
9450         eat(T_if);
9451
9452         PUSH_PARENT(statement);
9453
9454         add_anchor_token('{');
9455
9456         expect('(', end_error);
9457         add_anchor_token(')');
9458         expression_t *const expr = parse_expression();
9459         statement->ifs.condition = expr;
9460         /* §6.8.4.1:1  The controlling expression of an if statement shall have
9461          *             scalar type. */
9462         semantic_condition(expr, "condition of 'if'-statment");
9463         mark_vars_read(expr, NULL);
9464         rem_anchor_token(')');
9465         expect(')', end_error);
9466
9467 end_error:
9468         rem_anchor_token('{');
9469
9470         add_anchor_token(T_else);
9471         statement_t *const true_stmt = parse_statement();
9472         statement->ifs.true_statement = true_stmt;
9473         rem_anchor_token(T_else);
9474
9475         if (next_if(T_else)) {
9476                 statement->ifs.false_statement = parse_statement();
9477         } else if (warning.parentheses &&
9478                         true_stmt->kind == STATEMENT_IF &&
9479                         true_stmt->ifs.false_statement != NULL) {
9480                 warningf(&true_stmt->base.source_position,
9481                                 "suggest explicit braces to avoid ambiguous 'else'");
9482         }
9483
9484         POP_PARENT;
9485         return statement;
9486 }
9487
9488 /**
9489  * Check that all enums are handled in a switch.
9490  *
9491  * @param statement  the switch statement to check
9492  */
9493 static void check_enum_cases(const switch_statement_t *statement)
9494 {
9495         const type_t *type = skip_typeref(statement->expression->base.type);
9496         if (! is_type_enum(type))
9497                 return;
9498         const enum_type_t *enumt = &type->enumt;
9499
9500         /* if we have a default, no warnings */
9501         if (statement->default_label != NULL)
9502                 return;
9503
9504         /* FIXME: calculation of value should be done while parsing */
9505         /* TODO: quadratic algorithm here. Change to an n log n one */
9506         long            last_value = -1;
9507         const entity_t *entry      = enumt->enume->base.next;
9508         for (; entry != NULL && entry->kind == ENTITY_ENUM_VALUE;
9509              entry = entry->base.next) {
9510                 const expression_t *expression = entry->enum_value.value;
9511                 long                value      = expression != NULL ? fold_constant_to_int(expression) : last_value + 1;
9512                 bool                found      = false;
9513                 for (const case_label_statement_t *l = statement->first_case; l != NULL; l = l->next) {
9514                         if (l->expression == NULL)
9515                                 continue;
9516                         if (l->first_case <= value && value <= l->last_case) {
9517                                 found = true;
9518                                 break;
9519                         }
9520                 }
9521                 if (! found) {
9522                         warningf(&statement->base.source_position,
9523                                  "enumeration value '%Y' not handled in switch",
9524                                  entry->base.symbol);
9525                 }
9526                 last_value = value;
9527         }
9528 }
9529
9530 /**
9531  * Parse a switch statement.
9532  */
9533 static statement_t *parse_switch(void)
9534 {
9535         statement_t *statement = allocate_statement_zero(STATEMENT_SWITCH);
9536
9537         eat(T_switch);
9538
9539         PUSH_PARENT(statement);
9540
9541         expect('(', end_error);
9542         add_anchor_token(')');
9543         expression_t *const expr = parse_expression();
9544         mark_vars_read(expr, NULL);
9545         type_t       *      type = skip_typeref(expr->base.type);
9546         if (is_type_integer(type)) {
9547                 type = promote_integer(type);
9548                 if (warning.traditional) {
9549                         if (get_rank(type) >= get_akind_rank(ATOMIC_TYPE_LONG)) {
9550                                 warningf(&expr->base.source_position,
9551                                         "'%T' switch expression not converted to '%T' in ISO C",
9552                                         type, type_int);
9553                         }
9554                 }
9555         } else if (is_type_valid(type)) {
9556                 errorf(&expr->base.source_position,
9557                        "switch quantity is not an integer, but '%T'", type);
9558                 type = type_error_type;
9559         }
9560         statement->switchs.expression = create_implicit_cast(expr, type);
9561         expect(')', end_error);
9562         rem_anchor_token(')');
9563
9564         switch_statement_t *rem = current_switch;
9565         current_switch          = &statement->switchs;
9566         statement->switchs.body = parse_statement();
9567         current_switch          = rem;
9568
9569         if (warning.switch_default &&
9570             statement->switchs.default_label == NULL) {
9571                 warningf(&statement->base.source_position, "switch has no default case");
9572         }
9573         if (warning.switch_enum)
9574                 check_enum_cases(&statement->switchs);
9575
9576         POP_PARENT;
9577         return statement;
9578 end_error:
9579         POP_PARENT;
9580         return create_invalid_statement();
9581 }
9582
9583 static statement_t *parse_loop_body(statement_t *const loop)
9584 {
9585         statement_t *const rem = current_loop;
9586         current_loop = loop;
9587
9588         statement_t *const body = parse_statement();
9589
9590         current_loop = rem;
9591         return body;
9592 }
9593
9594 /**
9595  * Parse a while statement.
9596  */
9597 static statement_t *parse_while(void)
9598 {
9599         statement_t *statement = allocate_statement_zero(STATEMENT_WHILE);
9600
9601         eat(T_while);
9602
9603         PUSH_PARENT(statement);
9604
9605         expect('(', end_error);
9606         add_anchor_token(')');
9607         expression_t *const cond = parse_expression();
9608         statement->whiles.condition = cond;
9609         /* §6.8.5:2    The controlling expression of an iteration statement shall
9610          *             have scalar type. */
9611         semantic_condition(cond, "condition of 'while'-statement");
9612         mark_vars_read(cond, NULL);
9613         rem_anchor_token(')');
9614         expect(')', end_error);
9615
9616         statement->whiles.body = parse_loop_body(statement);
9617
9618         POP_PARENT;
9619         return statement;
9620 end_error:
9621         POP_PARENT;
9622         return create_invalid_statement();
9623 }
9624
9625 /**
9626  * Parse a do statement.
9627  */
9628 static statement_t *parse_do(void)
9629 {
9630         statement_t *statement = allocate_statement_zero(STATEMENT_DO_WHILE);
9631
9632         eat(T_do);
9633
9634         PUSH_PARENT(statement);
9635
9636         add_anchor_token(T_while);
9637         statement->do_while.body = parse_loop_body(statement);
9638         rem_anchor_token(T_while);
9639
9640         expect(T_while, end_error);
9641         expect('(', end_error);
9642         add_anchor_token(')');
9643         expression_t *const cond = parse_expression();
9644         statement->do_while.condition = cond;
9645         /* §6.8.5:2    The controlling expression of an iteration statement shall
9646          *             have scalar type. */
9647         semantic_condition(cond, "condition of 'do-while'-statement");
9648         mark_vars_read(cond, NULL);
9649         rem_anchor_token(')');
9650         expect(')', end_error);
9651         expect(';', end_error);
9652
9653         POP_PARENT;
9654         return statement;
9655 end_error:
9656         POP_PARENT;
9657         return create_invalid_statement();
9658 }
9659
9660 /**
9661  * Parse a for statement.
9662  */
9663 static statement_t *parse_for(void)
9664 {
9665         statement_t *statement = allocate_statement_zero(STATEMENT_FOR);
9666
9667         eat(T_for);
9668
9669         expect('(', end_error1);
9670         add_anchor_token(')');
9671
9672         PUSH_PARENT(statement);
9673
9674         size_t const  top       = environment_top();
9675         scope_t      *old_scope = scope_push(&statement->fors.scope);
9676
9677         bool old_gcc_extension = in_gcc_extension;
9678         while (next_if(T___extension__)) {
9679                 in_gcc_extension = true;
9680         }
9681
9682         if (next_if(';')) {
9683         } else if (is_declaration_specifier(&token, false)) {
9684                 parse_declaration(record_entity, DECL_FLAGS_NONE);
9685         } else {
9686                 add_anchor_token(';');
9687                 expression_t *const init = parse_expression();
9688                 statement->fors.initialisation = init;
9689                 mark_vars_read(init, ENT_ANY);
9690                 if (warning.unused_value && !expression_has_effect(init)) {
9691                         warningf(&init->base.source_position,
9692                                         "initialisation of 'for'-statement has no effect");
9693                 }
9694                 rem_anchor_token(';');
9695                 expect(';', end_error2);
9696         }
9697         in_gcc_extension = old_gcc_extension;
9698
9699         if (token.type != ';') {
9700                 add_anchor_token(';');
9701                 expression_t *const cond = parse_expression();
9702                 statement->fors.condition = cond;
9703                 /* §6.8.5:2    The controlling expression of an iteration statement
9704                  *             shall have scalar type. */
9705                 semantic_condition(cond, "condition of 'for'-statement");
9706                 mark_vars_read(cond, NULL);
9707                 rem_anchor_token(';');
9708         }
9709         expect(';', end_error2);
9710         if (token.type != ')') {
9711                 expression_t *const step = parse_expression();
9712                 statement->fors.step = step;
9713                 mark_vars_read(step, ENT_ANY);
9714                 if (warning.unused_value && !expression_has_effect(step)) {
9715                         warningf(&step->base.source_position,
9716                                  "step of 'for'-statement has no effect");
9717                 }
9718         }
9719         expect(')', end_error2);
9720         rem_anchor_token(')');
9721         statement->fors.body = parse_loop_body(statement);
9722
9723         assert(current_scope == &statement->fors.scope);
9724         scope_pop(old_scope);
9725         environment_pop_to(top);
9726
9727         POP_PARENT;
9728         return statement;
9729
9730 end_error2:
9731         POP_PARENT;
9732         rem_anchor_token(')');
9733         assert(current_scope == &statement->fors.scope);
9734         scope_pop(old_scope);
9735         environment_pop_to(top);
9736         /* fallthrough */
9737
9738 end_error1:
9739         return create_invalid_statement();
9740 }
9741
9742 /**
9743  * Parse a goto statement.
9744  */
9745 static statement_t *parse_goto(void)
9746 {
9747         statement_t *statement = allocate_statement_zero(STATEMENT_GOTO);
9748         eat(T_goto);
9749
9750         if (GNU_MODE && next_if('*')) {
9751                 expression_t *expression = parse_expression();
9752                 mark_vars_read(expression, NULL);
9753
9754                 /* Argh: although documentation says the expression must be of type void*,
9755                  * gcc accepts anything that can be casted into void* without error */
9756                 type_t *type = expression->base.type;
9757
9758                 if (type != type_error_type) {
9759                         if (!is_type_pointer(type) && !is_type_integer(type)) {
9760                                 errorf(&expression->base.source_position,
9761                                         "cannot convert to a pointer type");
9762                         } else if (warning.other && type != type_void_ptr) {
9763                                 warningf(&expression->base.source_position,
9764                                         "type of computed goto expression should be 'void*' not '%T'", type);
9765                         }
9766                         expression = create_implicit_cast(expression, type_void_ptr);
9767                 }
9768
9769                 statement->gotos.expression = expression;
9770         } else if (token.type == T_IDENTIFIER) {
9771                 symbol_t *symbol = token.symbol;
9772                 next_token();
9773                 statement->gotos.label = get_label(symbol);
9774         } else {
9775                 if (GNU_MODE)
9776                         parse_error_expected("while parsing goto", T_IDENTIFIER, '*', NULL);
9777                 else
9778                         parse_error_expected("while parsing goto", T_IDENTIFIER, NULL);
9779                 eat_until_anchor();
9780                 goto end_error;
9781         }
9782
9783         /* remember the goto's in a list for later checking */
9784         *goto_anchor = &statement->gotos;
9785         goto_anchor  = &statement->gotos.next;
9786
9787         expect(';', end_error);
9788
9789         return statement;
9790 end_error:
9791         return create_invalid_statement();
9792 }
9793
9794 /**
9795  * Parse a continue statement.
9796  */
9797 static statement_t *parse_continue(void)
9798 {
9799         if (current_loop == NULL) {
9800                 errorf(HERE, "continue statement not within loop");
9801         }
9802
9803         statement_t *statement = allocate_statement_zero(STATEMENT_CONTINUE);
9804
9805         eat(T_continue);
9806         expect(';', end_error);
9807
9808 end_error:
9809         return statement;
9810 }
9811
9812 /**
9813  * Parse a break statement.
9814  */
9815 static statement_t *parse_break(void)
9816 {
9817         if (current_switch == NULL && current_loop == NULL) {
9818                 errorf(HERE, "break statement not within loop or switch");
9819         }
9820
9821         statement_t *statement = allocate_statement_zero(STATEMENT_BREAK);
9822
9823         eat(T_break);
9824         expect(';', end_error);
9825
9826 end_error:
9827         return statement;
9828 }
9829
9830 /**
9831  * Parse a __leave statement.
9832  */
9833 static statement_t *parse_leave_statement(void)
9834 {
9835         if (current_try == NULL) {
9836                 errorf(HERE, "__leave statement not within __try");
9837         }
9838
9839         statement_t *statement = allocate_statement_zero(STATEMENT_LEAVE);
9840
9841         eat(T___leave);
9842         expect(';', end_error);
9843
9844 end_error:
9845         return statement;
9846 }
9847
9848 /**
9849  * Check if a given entity represents a local variable.
9850  */
9851 static bool is_local_variable(const entity_t *entity)
9852 {
9853         if (entity->kind != ENTITY_VARIABLE)
9854                 return false;
9855
9856         switch ((storage_class_tag_t) entity->declaration.storage_class) {
9857         case STORAGE_CLASS_AUTO:
9858         case STORAGE_CLASS_REGISTER: {
9859                 const type_t *type = skip_typeref(entity->declaration.type);
9860                 if (is_type_function(type)) {
9861                         return false;
9862                 } else {
9863                         return true;
9864                 }
9865         }
9866         default:
9867                 return false;
9868         }
9869 }
9870
9871 /**
9872  * Check if a given expression represents a local variable.
9873  */
9874 static bool expression_is_local_variable(const expression_t *expression)
9875 {
9876         if (expression->base.kind != EXPR_REFERENCE) {
9877                 return false;
9878         }
9879         const entity_t *entity = expression->reference.entity;
9880         return is_local_variable(entity);
9881 }
9882
9883 /**
9884  * Check if a given expression represents a local variable and
9885  * return its declaration then, else return NULL.
9886  */
9887 entity_t *expression_is_variable(const expression_t *expression)
9888 {
9889         if (expression->base.kind != EXPR_REFERENCE) {
9890                 return NULL;
9891         }
9892         entity_t *entity = expression->reference.entity;
9893         if (entity->kind != ENTITY_VARIABLE)
9894                 return NULL;
9895
9896         return entity;
9897 }
9898
9899 /**
9900  * Parse a return statement.
9901  */
9902 static statement_t *parse_return(void)
9903 {
9904         eat(T_return);
9905
9906         statement_t *statement = allocate_statement_zero(STATEMENT_RETURN);
9907
9908         expression_t *return_value = NULL;
9909         if (token.type != ';') {
9910                 return_value = parse_expression();
9911                 mark_vars_read(return_value, NULL);
9912         }
9913
9914         const type_t *const func_type = skip_typeref(current_function->base.type);
9915         assert(is_type_function(func_type));
9916         type_t *const return_type = skip_typeref(func_type->function.return_type);
9917
9918         source_position_t const *const pos = &statement->base.source_position;
9919         if (return_value != NULL) {
9920                 type_t *return_value_type = skip_typeref(return_value->base.type);
9921
9922                 if (is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
9923                         if (is_type_atomic(return_value_type, ATOMIC_TYPE_VOID)) {
9924                                 /* ISO/IEC 14882:1998(E) §6.6.3:2 */
9925                                 /* Only warn in C mode, because GCC does the same */
9926                                 if (c_mode & _CXX || strict_mode) {
9927                                         errorf(pos,
9928                                                         "'return' with a value, in function returning 'void'");
9929                                 } else if (warning.other) {
9930                                         warningf(pos,
9931                                                         "'return' with a value, in function returning 'void'");
9932                                 }
9933                         } else if (!(c_mode & _CXX)) { /* ISO/IEC 14882:1998(E) §6.6.3:3 */
9934                                 /* Only warn in C mode, because GCC does the same */
9935                                 if (strict_mode) {
9936                                         errorf(pos,
9937                                                         "'return' with expression in function returning 'void'");
9938                                 } else if (warning.other) {
9939                                         warningf(pos,
9940                                                         "'return' with expression in function returning 'void'");
9941                                 }
9942                         }
9943                 } else {
9944                         assign_error_t error = semantic_assign(return_type, return_value);
9945                         report_assign_error(error, return_type, return_value, "'return'",
9946                                         pos);
9947                 }
9948                 return_value = create_implicit_cast(return_value, return_type);
9949                 /* check for returning address of a local var */
9950                 if (warning.other && return_value != NULL
9951                                 && return_value->base.kind == EXPR_UNARY_TAKE_ADDRESS) {
9952                         const expression_t *expression = return_value->unary.value;
9953                         if (expression_is_local_variable(expression)) {
9954                                 warningf(pos, "function returns address of local variable");
9955                         }
9956                 }
9957         } else if (warning.other && !is_type_atomic(return_type, ATOMIC_TYPE_VOID)) {
9958                 /* ISO/IEC 14882:1998(E) §6.6.3:3 */
9959                 if (c_mode & _CXX || strict_mode) {
9960                         errorf(pos,
9961                                         "'return' without value, in function returning non-void");
9962                 } else {
9963                         warningf(pos,
9964                                         "'return' without value, in function returning non-void");
9965                 }
9966         }
9967         statement->returns.value = return_value;
9968
9969         expect(';', end_error);
9970
9971 end_error:
9972         return statement;
9973 }
9974
9975 /**
9976  * Parse a declaration statement.
9977  */
9978 static statement_t *parse_declaration_statement(void)
9979 {
9980         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
9981
9982         entity_t *before = current_scope->last_entity;
9983         if (GNU_MODE) {
9984                 parse_external_declaration();
9985         } else {
9986                 parse_declaration(record_entity, DECL_FLAGS_NONE);
9987         }
9988
9989         declaration_statement_t *const decl  = &statement->declaration;
9990         entity_t                *const begin =
9991                 before != NULL ? before->base.next : current_scope->entities;
9992         decl->declarations_begin = begin;
9993         decl->declarations_end   = begin != NULL ? current_scope->last_entity : NULL;
9994
9995         return statement;
9996 }
9997
9998 /**
9999  * Parse an expression statement, ie. expr ';'.
10000  */
10001 static statement_t *parse_expression_statement(void)
10002 {
10003         statement_t *statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10004
10005         expression_t *const expr         = parse_expression();
10006         statement->expression.expression = expr;
10007         mark_vars_read(expr, ENT_ANY);
10008
10009         expect(';', end_error);
10010
10011 end_error:
10012         return statement;
10013 }
10014
10015 /**
10016  * Parse a microsoft __try { } __finally { } or
10017  * __try{ } __except() { }
10018  */
10019 static statement_t *parse_ms_try_statment(void)
10020 {
10021         statement_t *statement = allocate_statement_zero(STATEMENT_MS_TRY);
10022         eat(T___try);
10023
10024         PUSH_PARENT(statement);
10025
10026         ms_try_statement_t *rem = current_try;
10027         current_try = &statement->ms_try;
10028         statement->ms_try.try_statement = parse_compound_statement(false);
10029         current_try = rem;
10030
10031         POP_PARENT;
10032
10033         if (next_if(T___except)) {
10034                 expect('(', end_error);
10035                 add_anchor_token(')');
10036                 expression_t *const expr = parse_expression();
10037                 mark_vars_read(expr, NULL);
10038                 type_t       *      type = skip_typeref(expr->base.type);
10039                 if (is_type_integer(type)) {
10040                         type = promote_integer(type);
10041                 } else if (is_type_valid(type)) {
10042                         errorf(&expr->base.source_position,
10043                                "__expect expression is not an integer, but '%T'", type);
10044                         type = type_error_type;
10045                 }
10046                 statement->ms_try.except_expression = create_implicit_cast(expr, type);
10047                 rem_anchor_token(')');
10048                 expect(')', end_error);
10049                 statement->ms_try.final_statement = parse_compound_statement(false);
10050         } else if (next_if(T__finally)) {
10051                 statement->ms_try.final_statement = parse_compound_statement(false);
10052         } else {
10053                 parse_error_expected("while parsing __try statement", T___except, T___finally, NULL);
10054                 return create_invalid_statement();
10055         }
10056         return statement;
10057 end_error:
10058         return create_invalid_statement();
10059 }
10060
10061 static statement_t *parse_empty_statement(void)
10062 {
10063         if (warning.empty_statement) {
10064                 warningf(HERE, "statement is empty");
10065         }
10066         statement_t *const statement = create_empty_statement();
10067         eat(';');
10068         return statement;
10069 }
10070
10071 static statement_t *parse_local_label_declaration(void)
10072 {
10073         statement_t *statement = allocate_statement_zero(STATEMENT_DECLARATION);
10074
10075         eat(T___label__);
10076
10077         entity_t *begin = NULL, *end = NULL;
10078
10079         do {
10080                 if (token.type != T_IDENTIFIER) {
10081                         parse_error_expected("while parsing local label declaration",
10082                                 T_IDENTIFIER, NULL);
10083                         goto end_error;
10084                 }
10085                 symbol_t *symbol = token.symbol;
10086                 entity_t *entity = get_entity(symbol, NAMESPACE_LABEL);
10087                 if (entity != NULL && entity->base.parent_scope == current_scope) {
10088                         errorf(HERE, "multiple definitions of '__label__ %Y' (previous definition %P)",
10089                                symbol, &entity->base.source_position);
10090                 } else {
10091                         entity = allocate_entity_zero(ENTITY_LOCAL_LABEL);
10092
10093                         entity->base.parent_scope    = current_scope;
10094                         entity->base.namespc         = NAMESPACE_LABEL;
10095                         entity->base.source_position = token.source_position;
10096                         entity->base.symbol          = symbol;
10097
10098                         if (end != NULL)
10099                                 end->base.next = entity;
10100                         end = entity;
10101                         if (begin == NULL)
10102                                 begin = entity;
10103
10104                         environment_push(entity);
10105                 }
10106                 next_token();
10107         } while (next_if(','));
10108         eat(';');
10109 end_error:
10110         statement->declaration.declarations_begin = begin;
10111         statement->declaration.declarations_end   = end;
10112         return statement;
10113 }
10114
10115 static void parse_namespace_definition(void)
10116 {
10117         eat(T_namespace);
10118
10119         entity_t *entity = NULL;
10120         symbol_t *symbol = NULL;
10121
10122         if (token.type == T_IDENTIFIER) {
10123                 symbol = token.symbol;
10124                 next_token();
10125
10126                 entity = get_entity(symbol, NAMESPACE_NORMAL);
10127                 if (entity != NULL
10128                                 && entity->kind != ENTITY_NAMESPACE
10129                                 && entity->base.parent_scope == current_scope) {
10130                         if (!is_error_entity(entity)) {
10131                                 error_redefined_as_different_kind(&token.source_position,
10132                                                 entity, ENTITY_NAMESPACE);
10133                         }
10134                         entity = NULL;
10135                 }
10136         }
10137
10138         if (entity == NULL) {
10139                 entity                       = allocate_entity_zero(ENTITY_NAMESPACE);
10140                 entity->base.symbol          = symbol;
10141                 entity->base.source_position = token.source_position;
10142                 entity->base.namespc         = NAMESPACE_NORMAL;
10143                 entity->base.parent_scope    = current_scope;
10144         }
10145
10146         if (token.type == '=') {
10147                 /* TODO: parse namespace alias */
10148                 panic("namespace alias definition not supported yet");
10149         }
10150
10151         environment_push(entity);
10152         append_entity(current_scope, entity);
10153
10154         size_t const  top       = environment_top();
10155         scope_t      *old_scope = scope_push(&entity->namespacee.members);
10156
10157         entity_t     *old_current_entity = current_entity;
10158         current_entity = entity;
10159
10160         expect('{', end_error);
10161         parse_externals();
10162         expect('}', end_error);
10163
10164 end_error:
10165         assert(current_scope == &entity->namespacee.members);
10166         assert(current_entity == entity);
10167         current_entity = old_current_entity;
10168         scope_pop(old_scope);
10169         environment_pop_to(top);
10170 }
10171
10172 /**
10173  * Parse a statement.
10174  * There's also parse_statement() which additionally checks for
10175  * "statement has no effect" warnings
10176  */
10177 static statement_t *intern_parse_statement(void)
10178 {
10179         statement_t *statement = NULL;
10180
10181         /* declaration or statement */
10182         add_anchor_token(';');
10183         switch (token.type) {
10184         case T_IDENTIFIER: {
10185                 token_type_t la1_type = (token_type_t)look_ahead(1)->type;
10186                 if (la1_type == ':') {
10187                         statement = parse_label_statement();
10188                 } else if (is_typedef_symbol(token.symbol)) {
10189                         statement = parse_declaration_statement();
10190                 } else {
10191                         /* it's an identifier, the grammar says this must be an
10192                          * expression statement. However it is common that users mistype
10193                          * declaration types, so we guess a bit here to improve robustness
10194                          * for incorrect programs */
10195                         switch (la1_type) {
10196                         case '&':
10197                         case '*':
10198                                 if (get_entity(token.symbol, NAMESPACE_NORMAL) != NULL)
10199                                         goto expression_statment;
10200                                 /* FALLTHROUGH */
10201
10202                         DECLARATION_START
10203                         case T_IDENTIFIER:
10204                                 statement = parse_declaration_statement();
10205                                 break;
10206
10207                         default:
10208 expression_statment:
10209                                 statement = parse_expression_statement();
10210                                 break;
10211                         }
10212                 }
10213                 break;
10214         }
10215
10216         case T___extension__:
10217                 /* This can be a prefix to a declaration or an expression statement.
10218                  * We simply eat it now and parse the rest with tail recursion. */
10219                 while (next_if(T___extension__)) {}
10220                 bool old_gcc_extension = in_gcc_extension;
10221                 in_gcc_extension       = true;
10222                 statement = intern_parse_statement();
10223                 in_gcc_extension = old_gcc_extension;
10224                 break;
10225
10226         DECLARATION_START
10227                 statement = parse_declaration_statement();
10228                 break;
10229
10230         case T___label__:
10231                 statement = parse_local_label_declaration();
10232                 break;
10233
10234         case ';':         statement = parse_empty_statement();         break;
10235         case '{':         statement = parse_compound_statement(false); break;
10236         case T___leave:   statement = parse_leave_statement();         break;
10237         case T___try:     statement = parse_ms_try_statment();         break;
10238         case T_asm:       statement = parse_asm_statement();           break;
10239         case T_break:     statement = parse_break();                   break;
10240         case T_case:      statement = parse_case_statement();          break;
10241         case T_continue:  statement = parse_continue();                break;
10242         case T_default:   statement = parse_default_statement();       break;
10243         case T_do:        statement = parse_do();                      break;
10244         case T_for:       statement = parse_for();                     break;
10245         case T_goto:      statement = parse_goto();                    break;
10246         case T_if:        statement = parse_if();                      break;
10247         case T_return:    statement = parse_return();                  break;
10248         case T_switch:    statement = parse_switch();                  break;
10249         case T_while:     statement = parse_while();                   break;
10250
10251         EXPRESSION_START
10252                 statement = parse_expression_statement();
10253                 break;
10254
10255         default:
10256                 errorf(HERE, "unexpected token %K while parsing statement", &token);
10257                 statement = create_invalid_statement();
10258                 if (!at_anchor())
10259                         next_token();
10260                 break;
10261         }
10262         rem_anchor_token(';');
10263
10264         assert(statement != NULL
10265                         && statement->base.source_position.input_name != NULL);
10266
10267         return statement;
10268 }
10269
10270 /**
10271  * parse a statement and emits "statement has no effect" warning if needed
10272  * (This is really a wrapper around intern_parse_statement with check for 1
10273  *  single warning. It is needed, because for statement expressions we have
10274  *  to avoid the warning on the last statement)
10275  */
10276 static statement_t *parse_statement(void)
10277 {
10278         statement_t *statement = intern_parse_statement();
10279
10280         if (statement->kind == STATEMENT_EXPRESSION && warning.unused_value) {
10281                 expression_t *expression = statement->expression.expression;
10282                 if (!expression_has_effect(expression)) {
10283                         warningf(&expression->base.source_position,
10284                                         "statement has no effect");
10285                 }
10286         }
10287
10288         return statement;
10289 }
10290
10291 /**
10292  * Parse a compound statement.
10293  */
10294 static statement_t *parse_compound_statement(bool inside_expression_statement)
10295 {
10296         statement_t *statement = allocate_statement_zero(STATEMENT_COMPOUND);
10297
10298         PUSH_PARENT(statement);
10299
10300         eat('{');
10301         add_anchor_token('}');
10302         /* tokens, which can start a statement */
10303         /* TODO MS, __builtin_FOO */
10304         add_anchor_token('!');
10305         add_anchor_token('&');
10306         add_anchor_token('(');
10307         add_anchor_token('*');
10308         add_anchor_token('+');
10309         add_anchor_token('-');
10310         add_anchor_token('{');
10311         add_anchor_token('~');
10312         add_anchor_token(T_CHARACTER_CONSTANT);
10313         add_anchor_token(T_COLONCOLON);
10314         add_anchor_token(T_FLOATINGPOINT);
10315         add_anchor_token(T_IDENTIFIER);
10316         add_anchor_token(T_INTEGER);
10317         add_anchor_token(T_MINUSMINUS);
10318         add_anchor_token(T_PLUSPLUS);
10319         add_anchor_token(T_STRING_LITERAL);
10320         add_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10321         add_anchor_token(T_WIDE_STRING_LITERAL);
10322         add_anchor_token(T__Bool);
10323         add_anchor_token(T__Complex);
10324         add_anchor_token(T__Imaginary);
10325         add_anchor_token(T___FUNCTION__);
10326         add_anchor_token(T___PRETTY_FUNCTION__);
10327         add_anchor_token(T___alignof__);
10328         add_anchor_token(T___attribute__);
10329         add_anchor_token(T___builtin_va_start);
10330         add_anchor_token(T___extension__);
10331         add_anchor_token(T___func__);
10332         add_anchor_token(T___imag__);
10333         add_anchor_token(T___label__);
10334         add_anchor_token(T___real__);
10335         add_anchor_token(T___thread);
10336         add_anchor_token(T_asm);
10337         add_anchor_token(T_auto);
10338         add_anchor_token(T_bool);
10339         add_anchor_token(T_break);
10340         add_anchor_token(T_case);
10341         add_anchor_token(T_char);
10342         add_anchor_token(T_class);
10343         add_anchor_token(T_const);
10344         add_anchor_token(T_const_cast);
10345         add_anchor_token(T_continue);
10346         add_anchor_token(T_default);
10347         add_anchor_token(T_delete);
10348         add_anchor_token(T_double);
10349         add_anchor_token(T_do);
10350         add_anchor_token(T_dynamic_cast);
10351         add_anchor_token(T_enum);
10352         add_anchor_token(T_extern);
10353         add_anchor_token(T_false);
10354         add_anchor_token(T_float);
10355         add_anchor_token(T_for);
10356         add_anchor_token(T_goto);
10357         add_anchor_token(T_if);
10358         add_anchor_token(T_inline);
10359         add_anchor_token(T_int);
10360         add_anchor_token(T_long);
10361         add_anchor_token(T_new);
10362         add_anchor_token(T_operator);
10363         add_anchor_token(T_register);
10364         add_anchor_token(T_reinterpret_cast);
10365         add_anchor_token(T_restrict);
10366         add_anchor_token(T_return);
10367         add_anchor_token(T_short);
10368         add_anchor_token(T_signed);
10369         add_anchor_token(T_sizeof);
10370         add_anchor_token(T_static);
10371         add_anchor_token(T_static_cast);
10372         add_anchor_token(T_struct);
10373         add_anchor_token(T_switch);
10374         add_anchor_token(T_template);
10375         add_anchor_token(T_this);
10376         add_anchor_token(T_throw);
10377         add_anchor_token(T_true);
10378         add_anchor_token(T_try);
10379         add_anchor_token(T_typedef);
10380         add_anchor_token(T_typeid);
10381         add_anchor_token(T_typename);
10382         add_anchor_token(T_typeof);
10383         add_anchor_token(T_union);
10384         add_anchor_token(T_unsigned);
10385         add_anchor_token(T_using);
10386         add_anchor_token(T_void);
10387         add_anchor_token(T_volatile);
10388         add_anchor_token(T_wchar_t);
10389         add_anchor_token(T_while);
10390
10391         size_t const  top       = environment_top();
10392         scope_t      *old_scope = scope_push(&statement->compound.scope);
10393
10394         statement_t **anchor            = &statement->compound.statements;
10395         bool          only_decls_so_far = true;
10396         while (token.type != '}') {
10397                 if (token.type == T_EOF) {
10398                         errorf(&statement->base.source_position,
10399                                "EOF while parsing compound statement");
10400                         break;
10401                 }
10402                 statement_t *sub_statement = intern_parse_statement();
10403                 if (is_invalid_statement(sub_statement)) {
10404                         /* an error occurred. if we are at an anchor, return */
10405                         if (at_anchor())
10406                                 goto end_error;
10407                         continue;
10408                 }
10409
10410                 if (warning.declaration_after_statement) {
10411                         if (sub_statement->kind != STATEMENT_DECLARATION) {
10412                                 only_decls_so_far = false;
10413                         } else if (!only_decls_so_far) {
10414                                 warningf(&sub_statement->base.source_position,
10415                                          "ISO C90 forbids mixed declarations and code");
10416                         }
10417                 }
10418
10419                 *anchor = sub_statement;
10420
10421                 while (sub_statement->base.next != NULL)
10422                         sub_statement = sub_statement->base.next;
10423
10424                 anchor = &sub_statement->base.next;
10425         }
10426         next_token();
10427
10428         /* look over all statements again to produce no effect warnings */
10429         if (warning.unused_value) {
10430                 statement_t *sub_statement = statement->compound.statements;
10431                 for (; sub_statement != NULL; sub_statement = sub_statement->base.next) {
10432                         if (sub_statement->kind != STATEMENT_EXPRESSION)
10433                                 continue;
10434                         /* don't emit a warning for the last expression in an expression
10435                          * statement as it has always an effect */
10436                         if (inside_expression_statement && sub_statement->base.next == NULL)
10437                                 continue;
10438
10439                         expression_t *expression = sub_statement->expression.expression;
10440                         if (!expression_has_effect(expression)) {
10441                                 warningf(&expression->base.source_position,
10442                                          "statement has no effect");
10443                         }
10444                 }
10445         }
10446
10447 end_error:
10448         rem_anchor_token(T_while);
10449         rem_anchor_token(T_wchar_t);
10450         rem_anchor_token(T_volatile);
10451         rem_anchor_token(T_void);
10452         rem_anchor_token(T_using);
10453         rem_anchor_token(T_unsigned);
10454         rem_anchor_token(T_union);
10455         rem_anchor_token(T_typeof);
10456         rem_anchor_token(T_typename);
10457         rem_anchor_token(T_typeid);
10458         rem_anchor_token(T_typedef);
10459         rem_anchor_token(T_try);
10460         rem_anchor_token(T_true);
10461         rem_anchor_token(T_throw);
10462         rem_anchor_token(T_this);
10463         rem_anchor_token(T_template);
10464         rem_anchor_token(T_switch);
10465         rem_anchor_token(T_struct);
10466         rem_anchor_token(T_static_cast);
10467         rem_anchor_token(T_static);
10468         rem_anchor_token(T_sizeof);
10469         rem_anchor_token(T_signed);
10470         rem_anchor_token(T_short);
10471         rem_anchor_token(T_return);
10472         rem_anchor_token(T_restrict);
10473         rem_anchor_token(T_reinterpret_cast);
10474         rem_anchor_token(T_register);
10475         rem_anchor_token(T_operator);
10476         rem_anchor_token(T_new);
10477         rem_anchor_token(T_long);
10478         rem_anchor_token(T_int);
10479         rem_anchor_token(T_inline);
10480         rem_anchor_token(T_if);
10481         rem_anchor_token(T_goto);
10482         rem_anchor_token(T_for);
10483         rem_anchor_token(T_float);
10484         rem_anchor_token(T_false);
10485         rem_anchor_token(T_extern);
10486         rem_anchor_token(T_enum);
10487         rem_anchor_token(T_dynamic_cast);
10488         rem_anchor_token(T_do);
10489         rem_anchor_token(T_double);
10490         rem_anchor_token(T_delete);
10491         rem_anchor_token(T_default);
10492         rem_anchor_token(T_continue);
10493         rem_anchor_token(T_const_cast);
10494         rem_anchor_token(T_const);
10495         rem_anchor_token(T_class);
10496         rem_anchor_token(T_char);
10497         rem_anchor_token(T_case);
10498         rem_anchor_token(T_break);
10499         rem_anchor_token(T_bool);
10500         rem_anchor_token(T_auto);
10501         rem_anchor_token(T_asm);
10502         rem_anchor_token(T___thread);
10503         rem_anchor_token(T___real__);
10504         rem_anchor_token(T___label__);
10505         rem_anchor_token(T___imag__);
10506         rem_anchor_token(T___func__);
10507         rem_anchor_token(T___extension__);
10508         rem_anchor_token(T___builtin_va_start);
10509         rem_anchor_token(T___attribute__);
10510         rem_anchor_token(T___alignof__);
10511         rem_anchor_token(T___PRETTY_FUNCTION__);
10512         rem_anchor_token(T___FUNCTION__);
10513         rem_anchor_token(T__Imaginary);
10514         rem_anchor_token(T__Complex);
10515         rem_anchor_token(T__Bool);
10516         rem_anchor_token(T_WIDE_STRING_LITERAL);
10517         rem_anchor_token(T_WIDE_CHARACTER_CONSTANT);
10518         rem_anchor_token(T_STRING_LITERAL);
10519         rem_anchor_token(T_PLUSPLUS);
10520         rem_anchor_token(T_MINUSMINUS);
10521         rem_anchor_token(T_INTEGER);
10522         rem_anchor_token(T_IDENTIFIER);
10523         rem_anchor_token(T_FLOATINGPOINT);
10524         rem_anchor_token(T_COLONCOLON);
10525         rem_anchor_token(T_CHARACTER_CONSTANT);
10526         rem_anchor_token('~');
10527         rem_anchor_token('{');
10528         rem_anchor_token('-');
10529         rem_anchor_token('+');
10530         rem_anchor_token('*');
10531         rem_anchor_token('(');
10532         rem_anchor_token('&');
10533         rem_anchor_token('!');
10534         rem_anchor_token('}');
10535         assert(current_scope == &statement->compound.scope);
10536         scope_pop(old_scope);
10537         environment_pop_to(top);
10538
10539         POP_PARENT;
10540         return statement;
10541 }
10542
10543 /**
10544  * Check for unused global static functions and variables
10545  */
10546 static void check_unused_globals(void)
10547 {
10548         if (!warning.unused_function && !warning.unused_variable)
10549                 return;
10550
10551         for (const entity_t *entity = file_scope->entities; entity != NULL;
10552              entity = entity->base.next) {
10553                 if (!is_declaration(entity))
10554                         continue;
10555
10556                 const declaration_t *declaration = &entity->declaration;
10557                 if (declaration->used                  ||
10558                     declaration->modifiers & DM_UNUSED ||
10559                     declaration->modifiers & DM_USED   ||
10560                     declaration->storage_class != STORAGE_CLASS_STATIC)
10561                         continue;
10562
10563                 type_t *const type = declaration->type;
10564                 const char *s;
10565                 if (entity->kind == ENTITY_FUNCTION) {
10566                         /* inhibit warning for static inline functions */
10567                         if (entity->function.is_inline)
10568                                 continue;
10569
10570                         s = entity->function.statement != NULL ? "defined" : "declared";
10571                 } else {
10572                         s = "defined";
10573                 }
10574
10575                 warningf(&declaration->base.source_position, "'%#T' %s but not used",
10576                         type, declaration->base.symbol, s);
10577         }
10578 }
10579
10580 static void parse_global_asm(void)
10581 {
10582         statement_t *statement = allocate_statement_zero(STATEMENT_ASM);
10583
10584         eat(T_asm);
10585         expect('(', end_error);
10586
10587         statement->asms.asm_text = parse_string_literals();
10588         statement->base.next     = unit->global_asm;
10589         unit->global_asm         = statement;
10590
10591         expect(')', end_error);
10592         expect(';', end_error);
10593
10594 end_error:;
10595 }
10596
10597 static void parse_linkage_specification(void)
10598 {
10599         eat(T_extern);
10600         assert(token.type == T_STRING_LITERAL);
10601
10602         const char *linkage = parse_string_literals().begin;
10603
10604         linkage_kind_t old_linkage = current_linkage;
10605         linkage_kind_t new_linkage;
10606         if (strcmp(linkage, "C") == 0) {
10607                 new_linkage = LINKAGE_C;
10608         } else if (strcmp(linkage, "C++") == 0) {
10609                 new_linkage = LINKAGE_CXX;
10610         } else {
10611                 errorf(HERE, "linkage string \"%s\" not recognized", linkage);
10612                 new_linkage = LINKAGE_INVALID;
10613         }
10614         current_linkage = new_linkage;
10615
10616         if (next_if('{')) {
10617                 parse_externals();
10618                 expect('}', end_error);
10619         } else {
10620                 parse_external();
10621         }
10622
10623 end_error:
10624         assert(current_linkage == new_linkage);
10625         current_linkage = old_linkage;
10626 }
10627
10628 static void parse_external(void)
10629 {
10630         switch (token.type) {
10631                 DECLARATION_START_NO_EXTERN
10632                 case T_IDENTIFIER:
10633                 case T___extension__:
10634                 /* tokens below are for implicit int */
10635                 case '&': /* & x; -> int& x; (and error later, because C++ has no
10636                              implicit int) */
10637                 case '*': /* * x; -> int* x; */
10638                 case '(': /* (x); -> int (x); */
10639                         parse_external_declaration();
10640                         return;
10641
10642                 case T_extern:
10643                         if (look_ahead(1)->type == T_STRING_LITERAL) {
10644                                 parse_linkage_specification();
10645                         } else {
10646                                 parse_external_declaration();
10647                         }
10648                         return;
10649
10650                 case T_asm:
10651                         parse_global_asm();
10652                         return;
10653
10654                 case T_namespace:
10655                         parse_namespace_definition();
10656                         return;
10657
10658                 case ';':
10659                         if (!strict_mode) {
10660                                 if (warning.other)
10661                                         warningf(HERE, "stray ';' outside of function");
10662                                 next_token();
10663                                 return;
10664                         }
10665                         /* FALLTHROUGH */
10666
10667                 default:
10668                         errorf(HERE, "stray %K outside of function", &token);
10669                         if (token.type == '(' || token.type == '{' || token.type == '[')
10670                                 eat_until_matching_token(token.type);
10671                         next_token();
10672                         return;
10673         }
10674 }
10675
10676 static void parse_externals(void)
10677 {
10678         add_anchor_token('}');
10679         add_anchor_token(T_EOF);
10680
10681 #ifndef NDEBUG
10682         unsigned char token_anchor_copy[T_LAST_TOKEN];
10683         memcpy(token_anchor_copy, token_anchor_set, sizeof(token_anchor_copy));
10684 #endif
10685
10686         while (token.type != T_EOF && token.type != '}') {
10687 #ifndef NDEBUG
10688                 bool anchor_leak = false;
10689                 for (int i = 0; i != T_LAST_TOKEN; ++i) {
10690                         unsigned char count = token_anchor_set[i] - token_anchor_copy[i];
10691                         if (count != 0) {
10692                                 errorf(HERE, "Leaked anchor token %k %d times", i, count);
10693                                 anchor_leak = true;
10694                         }
10695                 }
10696                 if (in_gcc_extension) {
10697                         errorf(HERE, "Leaked __extension__");
10698                         anchor_leak = true;
10699                 }
10700
10701                 if (anchor_leak)
10702                         abort();
10703 #endif
10704
10705                 parse_external();
10706         }
10707
10708         rem_anchor_token(T_EOF);
10709         rem_anchor_token('}');
10710 }
10711
10712 /**
10713  * Parse a translation unit.
10714  */
10715 static void parse_translation_unit(void)
10716 {
10717         add_anchor_token(T_EOF);
10718
10719         while (true) {
10720                 parse_externals();
10721
10722                 if (token.type == T_EOF)
10723                         break;
10724
10725                 errorf(HERE, "stray %K outside of function", &token);
10726                 if (token.type == '(' || token.type == '{' || token.type == '[')
10727                         eat_until_matching_token(token.type);
10728                 next_token();
10729         }
10730 }
10731
10732 /**
10733  * Parse the input.
10734  *
10735  * @return  the translation unit or NULL if errors occurred.
10736  */
10737 void start_parsing(void)
10738 {
10739         environment_stack = NEW_ARR_F(stack_entry_t, 0);
10740         label_stack       = NEW_ARR_F(stack_entry_t, 0);
10741         diagnostic_count  = 0;
10742         error_count       = 0;
10743         warning_count     = 0;
10744
10745         print_to_file(stderr);
10746
10747         assert(unit == NULL);
10748         unit = allocate_ast_zero(sizeof(unit[0]));
10749
10750         assert(file_scope == NULL);
10751         file_scope = &unit->scope;
10752
10753         assert(current_scope == NULL);
10754         scope_push(&unit->scope);
10755
10756         create_gnu_builtins();
10757         if (c_mode & _MS)
10758                 create_microsoft_intrinsics();
10759 }
10760
10761 translation_unit_t *finish_parsing(void)
10762 {
10763         assert(current_scope == &unit->scope);
10764         scope_pop(NULL);
10765
10766         assert(file_scope == &unit->scope);
10767         check_unused_globals();
10768         file_scope = NULL;
10769
10770         DEL_ARR_F(environment_stack);
10771         DEL_ARR_F(label_stack);
10772
10773         translation_unit_t *result = unit;
10774         unit = NULL;
10775         return result;
10776 }
10777
10778 /* §6.9.2:2 and §6.9.2:5: At the end of the translation incomplete arrays
10779  * are given length one. */
10780 static void complete_incomplete_arrays(void)
10781 {
10782         size_t n = ARR_LEN(incomplete_arrays);
10783         for (size_t i = 0; i != n; ++i) {
10784                 declaration_t *const decl      = incomplete_arrays[i];
10785                 type_t        *const orig_type = decl->type;
10786                 type_t        *const type      = skip_typeref(orig_type);
10787
10788                 if (!is_type_incomplete(type))
10789                         continue;
10790
10791                 if (warning.other) {
10792                         warningf(&decl->base.source_position,
10793                                         "array '%#T' assumed to have one element",
10794                                         orig_type, decl->base.symbol);
10795                 }
10796
10797                 type_t *const new_type = duplicate_type(type);
10798                 new_type->array.size_constant     = true;
10799                 new_type->array.has_implicit_size = true;
10800                 new_type->array.size              = 1;
10801
10802                 type_t *const result = identify_new_type(new_type);
10803
10804                 decl->type = result;
10805         }
10806 }
10807
10808 void prepare_main_collect2(entity_t *entity)
10809 {
10810         // create call to __main
10811         symbol_t *symbol         = symbol_table_insert("__main");
10812         entity_t *subsubmain_ent
10813                 = create_implicit_function(symbol, &builtin_source_position);
10814
10815         expression_t *ref         = allocate_expression_zero(EXPR_REFERENCE);
10816         type_t       *ftype       = subsubmain_ent->declaration.type;
10817         ref->base.source_position = builtin_source_position;
10818         ref->base.type            = make_pointer_type(ftype, TYPE_QUALIFIER_NONE);
10819         ref->reference.entity     = subsubmain_ent;
10820
10821         expression_t *call = allocate_expression_zero(EXPR_CALL);
10822         call->base.source_position = builtin_source_position;
10823         call->base.type            = type_void;
10824         call->call.function        = ref;
10825
10826         statement_t *expr_statement = allocate_statement_zero(STATEMENT_EXPRESSION);
10827         expr_statement->base.source_position  = builtin_source_position;
10828         expr_statement->expression.expression = call;
10829
10830         statement_t *statement = entity->function.statement;
10831         assert(statement->kind == STATEMENT_COMPOUND);
10832         compound_statement_t *compounds = &statement->compound;
10833
10834         expr_statement->base.next = compounds->statements;
10835         compounds->statements     = expr_statement;
10836 }
10837
10838 void parse(void)
10839 {
10840         lookahead_bufpos = 0;
10841         for (int i = 0; i < MAX_LOOKAHEAD + 2; ++i) {
10842                 next_token();
10843         }
10844         current_linkage   = c_mode & _CXX ? LINKAGE_CXX : LINKAGE_C;
10845         incomplete_arrays = NEW_ARR_F(declaration_t*, 0);
10846         parse_translation_unit();
10847         complete_incomplete_arrays();
10848         DEL_ARR_F(incomplete_arrays);
10849         incomplete_arrays = NULL;
10850 }
10851
10852 /**
10853  * Initialize the parser.
10854  */
10855 void init_parser(void)
10856 {
10857         sym_anonymous = symbol_table_insert("<anonymous>");
10858
10859         memset(token_anchor_set, 0, sizeof(token_anchor_set));
10860
10861         init_expression_parsers();
10862         obstack_init(&temp_obst);
10863
10864         symbol_t *const va_list_sym = symbol_table_insert("__builtin_va_list");
10865         type_valist = create_builtin_type(va_list_sym, type_void_ptr);
10866 }
10867
10868 /**
10869  * Terminate the parser.
10870  */
10871 void exit_parser(void)
10872 {
10873         obstack_free(&temp_obst, NULL);
10874 }